JP2007121037A - Measuring instrument for measuring distribution of behavior of protonic solvent in sample using magnetic resonance method, measuring method and program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a measuring instrument capable of accurately measuring the distribution of the behavior of a protonic solvent, a measuring method and a program. <P>SOLUTION: The measuring instrument 1 has: a magnet 113 for applying a static magnetic field to a sample 115; a plurality of small-sized RF coils 114 for applying an exciting vibration magnetic field to the sample 115 to acquire the nuclear magnetic resonance signal produced in the sample 115; an arithmetic part 130 for calculating the behavior of the protonic solvent on the basis of the nuclear magnetic resonance signal acquired by the small-sized RF coils 114; and an RF pulse forming part for sending out an RF pulse to the respective small-sized RF coils 114. The RF pulse forming part has an oscillator 102, a setting part 200 for setting the frequency of the oscillator 102 and a modulator 104 for modulating the signal oscillated by the oscillator 102. The setting part 200 sets the frequency of the oscillator 102 so that the frequency of the oscillator 102 is synchronized with the resonance frequency of nuclear magnetization at the installation position of each of the respective small-sized RF coils 114. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a technique for measuring the distribution of the behavior of a protic solvent in a sample using a magnetic resonance method.

In certain functional materials, the movement of solvent molecules in the material can dominate the performance of the material. When designing and developing such materials, or when equipment using these materials is in operation, it is important to measure the ease of movement of solvent molecules and the amount of solvent locally. .
Examples of such functional materials include solid polymer electrolyte membranes used in fuel cells.
In a fuel cell using a solid polymer electrolyte membrane, the power generation characteristics and efficiency strongly depend on the ionic conductivity of the solid polymer electrolyte membrane. In order to maintain high power generation characteristics, it is necessary to maintain high ionic conductivity of the solid polymer electrolyte membrane. The ionic conductivity of the membrane is caused by the movement of hydrogen ions within the membrane. Hydrogen ions do not move in the membrane alone, but several water molecules are arranged around them and the charge is offset by polar water molecules so that hydrogen ions can exist stably in the membrane. It moves with water molecules in the membrane while protecting it. Water molecules that move with hydrogen ions are called “associated water” and play an important role in maintaining high ionic conductivity of the solid polymer electrolyte membrane. Due to the transport mechanism in these solid polymer electrolyte membranes, the ionic conductivity in the solid polymer electrolyte membrane is determined by the amount of water molecules (protic solvent) contained in the membrane (the wet amount of the membrane) and the water in the membrane. It is known to be determined by the ease of movement (mobility) of molecules.

Conventionally, as a method of measuring the moisture content and the mobility of water molecules, the magnetic resonance (NMR) method was used to measure the whole sample and average the `` water molecule amount '' and `` water molecule self-diffusion coefficient '' The method of measuring was adopted (refer nonpatent literature 1).
However, with this method, only the amount of water and the mobility of water molecules in the entire sample could be grasped, and local measurement could not be performed.
Thus, a technique for locally measuring the amount of water molecules and a technique for locally measuring the mobility of water molecules have been proposed (Japanese Patent Application Nos. 2005-118138 and 2005-113777).
This technique uses a small RF coil that is smaller than the sample, and enables local measurement of the amount of water and the mobility of water molecules. In addition, it is said that by using a plurality of small RF coils, it is possible to grasp the moisture content and the mobility distribution of water molecules.
In a fuel cell or the like, since the power generation situation differs between the upstream side to which fuel or air is supplied and the downstream side from which these are discharged, the amount of moisture from the upstream side to the downstream side of the solid polymer electrolyte membrane, A mobility distribution of water molecules will result.
If such a distribution can be grasped and the state of the solid polymer electrolyte membrane can be accurately grasped, the supply amount of fuel and water vapor can be optimally controlled, and the performance of the fuel cell can be improved. It is expected to be possible.

E. O. Stejskal and J.M. E. Tanner, “Spin diffusion measurements: Spin Echoes in the Presence of a Time-Dependent Field Gradient,” Journal of chemical physics, vol. 42, no. 1, 1965, pp. 288-292

Thus, the distribution of the behavior of the protic solvent such as the distribution of water content, the mobility distribution of water molecules (for example, the spatial distribution of the water content, the mobility of water molecules, and the spatial distribution). However, it is difficult to meet such a demand with the above-described technology.
In order to accurately grasp the behavior of the protic solvent in the sample using the magnetic resonance method, it is necessary to acquire a magnetic resonance signal in accordance with the nuclide to be measured and the resonance frequency (magnetic resonance frequency) of the electron spin. is important. That is, it is considered that accurate measurement can be performed by acquiring a magnetic resonance signal in accordance with the nuclide to be measured and the resonance frequency of the electron spin.
Here, the nuclide to be measured and the resonance frequency of the electron spin change depending on the strength of the static magnetic field. The static magnetic field strength is not completely uniform and changes depending on the installation position of the small RF coil. That is, if a plurality of small RF coils are installed at different positions, the nuclear magnetization and the resonance frequency of electron spin differ for each installation position of each small RF coil.
Further, if a static magnetic field is applied to the sample by a magnet such as a permanent magnet that is likely to change in temperature, the static magnetic field strength is increased or decreased by the temperature change of the magnet, and accordingly, the resonance frequency is also increased or decreased. An increase in the temperature of the magnet reduces the strength of the static magnetic field, thereby reducing the resonance frequency. In a permanent magnet that does not have a temperature adjustment function, it is considered that the magnet temperature changes depending on the ambient temperature where the magnet is placed, and the magnetic field strength varies by about 1 ppm / min. In particular, in a small permanent magnet of 200 kg or less, the static magnetic field strength may fluctuate significantly as the magnet temperature fluctuates.
Further, when a magnet such as an electromagnet is used, the amount of current may change due to a change in resistance value such as heat generation of the coil, and the static magnetic field strength may fluctuate.

In the above-described conventional technology, since the distribution of the static magnetic field strength and the fluctuation of the static magnetic field strength are not considered, it is estimated that it is difficult to more accurately grasp the distribution of the behavior of the protic solvent.
In order to grasp the distribution of the behavior of the protic solvent more accurately, irradiation with an RF pulse having a frequency corresponding to the resonance frequency of the nuclear magnetization and electron spin at the position where each small RF coil is arranged is performed. It is considered that a magnetic resonance signal corresponding to the resonance frequency of the spin must be acquired.

  An object of the present invention is to provide a measuring apparatus, a measuring method, and a program capable of accurately measuring the behavior distribution of a protic solvent.

According to the present invention, an apparatus for measuring the distribution of the behavior of a protic solvent in a sample using a magnetic resonance method,
A static magnetic field application unit that applies a static magnetic field to the sample;
A plurality of small RF coils smaller than the sample for applying an oscillating magnetic field for excitation to the sample and acquiring a magnetic resonance signal generated at a specific location in the sample;
Based on the magnetic resonance signal acquired by each of the small RF coils, a calculation unit that calculates the distribution of the behavior of the protic solvent,
An output unit for outputting the distribution of the behavior of the protic solvent calculated by the calculation unit;
An RF pulse generator for generating an RF pulse for generating the excitation oscillating magnetic field in each of the small RF coils, and
The RF pulse generator is
An oscillator that oscillates a signal of a predetermined frequency;
A setting unit for setting the frequency of the oscillator;
A modulator that modulates a signal oscillated by the oscillator and generates an RF pulse;
The setting unit tunes the frequency of the oscillator to the magnetic resonance frequency at the installation position of each small RF coil when the static magnetic field is applied to the sample by the static magnetic field application unit, and the oscillator Set the frequency of
Provided is a measuring apparatus, wherein the modulator modulates a signal oscillated from the oscillator whose frequency is set by the setting unit, and generates an RF pulse having the frequency set by the setting unit. Is done.

According to the present invention, the setting unit for setting the frequency of the oscillator in synchronization with the magnetic resonance frequency at the installation position of each small RF coil in a state where a static magnetic field is applied to the sample is provided. Therefore, an RF pulse having a frequency corresponding to the magnetic resonance frequency at the installation position of each small RF coil can be irradiated from each small RF coil.
Thereby, the magnetic resonance signal according to the magnetic resonance frequency in the installation position of each small RF coil can be acquired via each small RF coil, and the distribution of the behavior of the protic solvent can be accurately grasped. .

In addition, the frequency of the oscillator can be set manually based on the magnetic resonance frequency at the installation position of each small RF coil of the sample to which a static magnetic field is applied. It takes time and effort to adjust and set the machine frequency.
On the other hand, the measuring apparatus of the present invention includes a setting unit that sets the frequency of the oscillator in synchronization with the magnetic resonance frequency at the installation position of each small RF coil when a static magnetic field is applied. There is no need for troublesome setting.

Here, examples of the “behavior of the protic solvent” measured by the present invention include the amount of the protic solvent, the mobility of the protic solvent, and the amount of movement of the protic solvent.
“Mobility” refers to a physical property value indicating the ease of movement of a protic solvent in a sample. Such physical property values include parameters such as self-diffusion coefficient and mobility (movement speed).
Moreover, in this specification, a protic solvent means the solvent which dissociates itself and produces a proton. Examples of protic solvents include water;
Alcohols such as methanol and ethanol;
Carboxylic acids such as acetic acid;
Phenol;
Liquid ammonia;
Is mentioned. Among these, when the protic solvent is water or alcohol, the behavior of the protic solvent such as the amount of the protic solvent and the mobility of the protic solvent can be measured more stably.
In the present invention, the frequency of the oscillator is set by tuning to the magnetic resonance frequency at the installation position of each small RF coil. However, the frequency of the oscillator does not have to completely match the magnetic resonance frequency. For example, a deviation that does not affect the reliability of the measured value, for example, a deviation of about 10 Hz is allowed.

The “magnetic resonance method” in the present invention includes both a nuclear magnetic resonance method (NMR) and an electron spin resonance method (ESR). Among these, if the measurement using nuclear magnetic resonance is used, the behavior of the protic solvent at a specific location in the sample can be stably measured as described later in the section of the embodiment.
Further, the “magnetic resonance frequency” in the present invention means the resonance frequency of nuclear magnetization or the resonance frequency of electron spin.
Furthermore, the “distribution of the behavior of the protic solvent” in the present invention may be, for example, a spatial distribution indicating the behavior of the protic solvent at the installation position of each small RF coil at a certain time. It may be a distribution showing a temporal change in the behavior of the protic solvent at the installation position of each small RF coil.

At this time, the setting unit stores a time-dependent change in magnetic resonance frequency of the installation position of at least one small RF coil in a state where the static magnetic field is applied to the sample;
A frequency calculation unit that calculates a magnetic resonance frequency at the installation position of at least the one small RF coil when the static magnetic field is applied to the sample;
From the change over time of the magnetic resonance frequency stored in the first storage unit and the magnetic resonance frequency at the installation position of at least the one small RF coil at the predetermined time calculated by the frequency calculation unit, the protic solvent An estimator for estimating a magnetic resonance frequency of at least the one small RF coil installation position at the measurement time of the behavior;
It is preferable to provide.

As described above, when a static magnetic field is applied by a magnet that easily changes in temperature, such as a permanent magnet, the static magnetic field strength increases or decreases due to the temperature change of the magnet over time, and the magnetic resonance frequency is reduced. fluctuate.
Further, when a magnet such as an electromagnet is used, the amount of current may change due to a change in resistance value such as heat generation of the coil, and the static magnetic field strength may vary.
When the fluctuation of the static magnetic field strength is large, after grasping the magnetic resonance frequency at the installation positions of all the small RF coils, if the behavior of the protic solvent is measured, the magnetism at the installation positions of the small RF coils is determined. The magnetic resonance frequency at the time of grasping the resonance frequency is greatly different from the magnetic resonance frequency at the time of measurement. Therefore, accurate measurement cannot be performed.

  In contrast, in the present invention, since the estimation unit is provided, the temporal change of the magnetic resonance frequency stored in the first storage unit and the position of one small RF coil at the predetermined time calculated by the frequency calculation unit From this magnetic resonance frequency, the magnetic resonance frequency at the position of one small RF coil at the measurement time of the behavior of the protic solvent can be estimated. Therefore, it is possible to accurately grasp the magnetic resonance frequency at the measurement time of the behavior of the protic solvent. Thereby, since the RF pulse of the frequency according to the magnetic resonance frequency of the position of the one small RF coil at the measurement time can be irradiated, the behavior of the protic solvent can be grasped more accurately.

At this time, the setting unit calculates a magnetic resonance frequency at an installation position of one small RF coil and a magnetic resonance frequency at an installation position of another small RF coil when the static magnetic field is applied to the sample. A correlation storage unit for storing the correlation;
A frequency calculating unit that calculates a magnetic resonance frequency at an installation position of the one small RF coil when the static magnetic field is applied to the sample;
Based on the magnetic resonance frequency at the installation position of the one small RF coil calculated by the frequency calculation unit and the correlation stored in the correlation storage unit, the magnetic resonance at the installation position of another small RF coil. And a prediction unit that predicts a frequency.

Here, the correlation between the magnetic resonance frequency at the installation position of one small RF coil and the magnetic resonance frequency at the installation position of another small RF coil is the magnetic resonance frequency at the installation position of one small RF coil, It is a relationship indicating the difference from the magnetic resonance frequency at the installation position of other small RF coils and the ratio thereof. If the magnetic resonance frequency at the installation position of one small RF coil is grasped from this correlation, the magnetic resonance frequency at the installation position of another small RF coil can be grasped.
For example, the correlation may be a function indicating the relationship between the magnetic resonance frequency at the installation position of one small RF coil and the magnetic resonance frequency at the installation position of another small RF coil.
Further, the prediction unit of the present invention calculates the magnetic resonance frequency at the installation position of another small RF coil using the magnetic resonance frequency at the installation position of one small RF coil and the correlation.

Thus, if the correlation between the magnetic resonance frequency at the installation position of one small RF coil and the magnetic resonance frequency at the installation position of another small RF coil is stored in the correlation storage unit, the frequency calculation unit After calculating the magnetic resonance frequency at the installation position of one small RF coil, based on the magnetic resonance frequency at the installation position of one small RF coil and the correlation stored in the correlation storage unit, The magnetic resonance frequency at the installation position of the small RF coil can be predicted.
Thereby, the magnetic resonance frequency in the installation position of another small RF coil can be quickly grasped, and time is not required for setting the frequency of the oscillator.

Here, the correlation storage unit stores in advance a static magnetic field strength distribution when a static magnetic field is applied to the sample,
Based on the static magnetic field strength distribution stored in the correlation storage unit, a resonance frequency distribution calculation unit that calculates a magnetic resonance frequency distribution of the sample,
The magnetic resonance frequency distribution of the sample calculated by the resonance frequency distribution calculation unit is preferably stored in the correlation storage unit as the correlation.
In general, the static magnetic field intensity distribution of the static magnetic field application unit is often grasped in advance when the static magnetic field application unit is manufactured. Since the magnetic resonance frequency distribution of the sample can be easily calculated from the static magnetic field strength distribution, the magnetic resonance frequency distribution of the sample can be easily grasped.

At this time, the setting unit includes a frequency calculation unit that calculates a magnetic resonance frequency at an installation position of at least the one small RF coil when the static magnetic field is applied to the sample.
When oscillating a signal of a predetermined frequency from the oscillator and applying an excitation oscillating magnetic field to the sample from the one small RF coil,
The frequency calculation unit obtains a magnetic resonance signal through the one small RF coil,
Calculate the frequency of the imaginary part or real part of the acquired magnetic resonance signal,
It is preferable to calculate the magnetic resonance frequency at the installation position of at least the one small RF coil based on the frequency of the imaginary part or the real part and the frequency of the signal oscillated from the oscillator.

Here, the frequency calculation unit acquires the magnetic resonance signal after being detected by a fundamental wave having a certain frequency oscillated from the oscillator (a signal having a predetermined frequency oscillated from the oscillator). Acquired when there is a difference between the frequency of the oscillator and the magnetic resonance frequency (magnetic resonance frequency at the installation position of one small RF coil) determined by the static magnetic field intensity at the installation position of one small RF coil The frequency difference is seen in the magnetic resonance signal. This frequency difference is seen as if the waveform representing the imaginary part and the real part is rotating or oscillating across the horizontal axis that is the time axis.
Therefore, the frequency at which the oscillator oscillates from the state in which the waveform representing the imaginary part and real part of the magnetic resonance signal acquired by the frequency calculation unit intersects the time axis (the frequency of the imaginary part or real part of the magnetic resonance signal). And the magnetic resonance frequency determined by the static magnetic field strength can be calculated.
Thereby, the magnetic resonance frequency (magnetic resonance frequency at the installation position of one small RF coil) determined by the static magnetic field intensity at the installation position of one small RF coil can be calculated.
If there is no difference between the frequency of the oscillator and the magnetic resonance frequency determined by the static magnetic field intensity at the position where one small RF coil is installed, the magnetic resonance signal appears not to rotate or vibrate.

Furthermore, the behavior of the protic solvent is preferably at least one of the amount of protic solvent, the mobility of the protic solvent, and the amount of movement of the protic solvent.
Here, the amount of movement of the protic solvent is calculated based on the amount of the protic solvent and the mobility of the protic solvent.
According to this configuration, at least the amount of the protic solvent, the mobility of the protic solvent, and the distribution of the amount of movement of the protic solvent can be grasped.

Furthermore, at this time, the behavior of the protic solvent is at least one of the amount of protic solvent and the mobility of the protic solvent,
A gradient magnetic field application unit for applying a gradient magnetic field to the sample;
Select one of a plurality of measurement modes including a first measurement mode for measuring the amount of the protic solvent in the sample and a second measurement mode for measuring the mobility of the protic solvent in the sample. A mode selection unit to
A control unit that controls the operation of the small RF coil and the gradient magnetic field application unit according to the measurement mode selected by the mode selection unit,
The calculation unit includes a first calculation unit that calculates the amount of protic solvent in the sample based on the magnetic resonance signal acquired in the first measurement mode;
A second calculator that calculates the mobility of the protic solvent in the sample based on the magnetic resonance signal acquired in the second measurement mode,
The controller is
When in the first measurement mode, an excitation oscillating magnetic field is applied to the sample by the small RF coil, and a magnetic resonance signal generated at the specific location corresponding to the excitation oscillating magnetic field is applied to the small sample. Acquired by RF coil,
When in the second measurement mode, an excitation oscillating magnetic field is applied to the sample by the small RF coil and a gradient magnetic field is applied by the gradient magnetic field application unit, and magnetism generated corresponding to these magnetic fields is generated. It is preferable that the resonance signal is acquired by the small RF coil.

According to this configuration, in the measurement mode for measuring the amount of protic solvent, the distribution of the amount of protic solvent can be measured using a plurality of small RF coils smaller than the sample. Also in the measurement mode for measuring the mobility, the mobility distribution can be measured using the gradient magnetic field applying unit and the small RF coil.
In addition, the same small RF coil was used to measure the amount of protic solvent and the mobility of the protic solvent. The amount of protic solvent and the mobility of the protic solvent were measured. It can be measured at the same position. Thereby, the distribution of the behavior of the protic solvent in the sample can be accurately grasped based on the amount of the protic solvent and the mobility of the protic solvent.

The present invention can be established not only as a measurement apparatus but also as a measurement method and a program.
That is, according to the present invention, a static magnetic field application unit that applies a static magnetic field to a sample, an excitation vibration magnetic field to the sample, and a magnetic resonance signal generated at a specific location in the sample A plurality of small RF coils that are smaller than the sample to be acquired, a calculation unit that calculates the behavior of the protic solvent based on the magnetic resonance signal acquired by the small RF coil, and a signal having a predetermined frequency are oscillated. An oscillator, a setting unit for setting a frequency of the oscillator, and a modulator for generating an RF pulse by modulating a signal from the oscillator, and generating the excitation oscillating magnetic field in each of the small RF coils A measurement method for measuring the distribution of the behavior of a protic solvent in a sample using an RF pulse generation unit that generates an RF pulse of
Applying a static magnetic field from the static magnetic field application unit to the sample;
The frequency of the oscillator is tuned to the magnetic resonance frequency at the installation position of each small RF coil of the sample to which the static magnetic field is applied by the setting unit of the RF pulse generation unit, and the frequency of the oscillator is set. And a process of
A signal having the frequency set in the step of setting the frequency of the oscillator is oscillated from the oscillator, and a signal from the oscillator is modulated by the modulator to generate an RF pulse. On the other hand, a step of transmitting an RF pulse having a frequency corresponding to the magnetic resonance frequency at the installation position of each small RF coil;
Applying an oscillating magnetic field for excitation from each of the small RF coils to the sample;
Obtaining a magnetic resonance signal generated at a specific location in the sample via each small RF coil;
And a step of calculating a behavior distribution of the protic solvent in the sample based on the acquired magnetic resonance signal.

In addition, according to the present invention, a static magnetic field application unit that applies a static magnetic field to a sample, an excitation vibration magnetic field to the sample, and a magnetic resonance signal generated at a specific location in the sample A plurality of small RF coils that are smaller than the sample to be acquired, a calculation unit that calculates the behavior of the protic solvent based on the magnetic resonance signal acquired by the small RF coil, and a signal having a predetermined frequency are oscillated. An oscillator, a setting unit for setting a frequency of the oscillator, and a modulator for generating an RF pulse by modulating a signal from the oscillator, and generating the excitation oscillating magnetic field in each of the small RF coils A program for controlling a measurement apparatus including an RF pulse generation unit for generating an RF pulse and measuring a behavior distribution of a protic solvent in a sample,
Applying a static magnetic field from the static magnetic field application unit to the sample;
The frequency of the oscillator is tuned to the magnetic resonance frequency at the installation position of each small RF coil of the sample to which the static magnetic field is applied by the setting unit of the RF pulse generation unit, and the frequency of the oscillator is set. And a process of
A signal having the frequency set in the step of setting the frequency of the oscillator is oscillated from the oscillator, and a signal from the oscillator is modulated by the modulator to generate an RF pulse. On the other hand, a step of transmitting an RF pulse having a frequency corresponding to the magnetic resonance frequency at the installation position of each small RF coil;
Applying an oscillating magnetic field for excitation from each of the small RF coils to the sample;
Obtaining a magnetic resonance signal generated at a specific location in the sample via each small RF coil;
There is also provided a program characterized in that, based on the acquired magnetic resonance signal, a calculation unit executes a step of calculating a behavior distribution of a protic solvent in the sample.

  ADVANTAGE OF THE INVENTION According to this invention, the measuring apparatus, measuring method, and program which can measure the distribution of the behavior of a protic solvent correctly are provided.

(Measurement principle)
First, the measurement principle of the distribution of the amount of water (protic solvent amount) and the ease of movement of water molecules (mobility) in each embodiment to be described later will be described with an example.
Here, the measurement principle of water content and mobility distribution using the nuclear magnetic resonance method will be described as an example.

  By switching and measuring the following first mode (A) and second mode (B), the moisture content of the sample and the ease of movement of water molecules (mobility) can be distributed. Obtainable. Further, by performing the following (C), it is possible to obtain a distribution of the amount of movement of water molecules in the sample.

(A) Calculate the T ₂ relaxation time constant by the CPMG (Carr-Purcell-Meiboom-Gill) method, and then calculate the local water content of the sample using the conversion table of “T ₂ and water content”. , Grasp the distribution of moisture content.
(B) By applying a gradient magnetic field and measuring the self-diffusion coefficient of water molecules by the PGSE (Pulsed-Gradient Spin-Echo) method, the mobility of local water molecules in the sample is calculated. Understand the distribution of mobility.
(C) Furthermore, if necessary, the distribution of the amount of movement of water molecules can be calculated based on the amount of water and mobility calculated from (A) and (B).

First, calculation of moisture content will be described.
(A) Calculation of Moisture Content FIG. 1 is a flowchart showing an outline of calculation of the moisture content.
First, a sample is placed in a space where magnets are arranged, and a static magnetic field is applied to the sample (S102).
In this state, an oscillating magnetic field for excitation is applied to the sample via a small RF coil, and an NMR signal (echo signal) corresponding to this is acquired (S104). The excitation oscillating magnetic field is a high-frequency pulse irradiated to the measurement target nucleus in the sample, and the NMR signal is a nuclear magnetic resonance signal emitted from the measurement target nucleus in the sample by the nuclear magnetic resonance phenomenon caused by the excitation oscillating magnetic field. is there.
Next, a T ₂ relaxation time constant is calculated from this echo signal (S106).
From this T ₂ relaxation time constant, the local water content in the sample is measured (S108). Specifically, data indicating the correlation between the amount of water in the sample and the T ₂ relaxation time constant is acquired, and the local amount of water at a specific location in the sample is obtained from this data and the T ₂ relaxation time constant. Ask for. Thereafter, the result is output (S110).
By performing such an operation (step 104 to step 110) via each small RF coil, it is possible to grasp the moisture content distribution.

Hereinafter, step 104 to step 108 will be described in detail.
(I) Step 104 (Application of excitation high-frequency pulse and acquisition of NMR signal)
Step 104 will be described in detail below. In step 104, an excitation high-frequency pulse is applied to the sample. The excitation high-frequency pulse is preferably a pulse sequence composed of a plurality of pulses, and an echo signal group corresponding to the pulse sequence is acquired. By doing so, the T ₂ relaxation time constant can be accurately obtained. The pulse sequence is preferably composed of the following (a) and (b).
(A) a 90 ° pulse, and
(B) n 180 ° pulses applied at intervals of time 2τ, starting after the time τ of the pulse in (a) has elapsed.

In the present embodiment, the T ₂ (lateral) relaxation time constant is calculated using the CPMG method.
Hydrogen nuclei placed in a static magnetic field have a net magnetization vector in a direction along the static magnetic field (for convenience, the Z direction). By irradiating an RF wave of a specific frequency (referred to as a resonance frequency) from the outside along the X-axis direction perpendicular to the Z-axis, the magnetization vector tilts in the positive direction of the Y-axis, and the nuclear magnetic resonance signal (Referred to as NMR signal) can be observed.

First, the magnetization vector is tilted in the positive direction of the Y-axis by a 90 ° pulse, and after τ time, the 180 ° excitation pulse is irradiated from the outside in the “Y-axis direction”, and the magnetization vector is set to “Y-axis as a symmetry axis”. "Invert. As a result, after 2τ time, the magnetization vector converges on the “positive direction” of the Y axis, and an echo signal having a large amplitude is observed. Furthermore, after 180 hours, the magnetization vector is irradiated with a 180 ° excitation pulse from the outside in the “Y-axis direction” and converged again on the “positive direction” on the Y-axis, and an echo signal having a large amplitude after 4τ time. Observe. Further, irradiation with 180 ° pulses is continued at the same 2τ interval. During this time, the peak intensity of the even-numbered echo signals of 2τ, 4τ, 6τ,... Is extracted and fitted with an exponential function, whereby the T ₂ (lateral) relaxation time constant by the CPMG method can be calculated.

  As described above, in the present embodiment, the magnetization vector is inverted “with the Y axis as the symmetry axis”, and thus the following compensation function appears. FIG. 2 is a diagram for explaining the compensation function of the pulse echo method of the present embodiment. The coordinates shown in the figure are a rotating coordinate system. Consider P and Q as nuclear magnetization in a small region in the sample where the inhomogeneity of the static magnetic field is negligible. Let the magnetic field at P be stronger than the magnetic field at Q. At this time, as shown in FIG. 2A, when a 90 ° pulse is applied in the x′-axis direction, the nuclear magnetization of P and Q starts precession from the same location (y′-axis) in the rotating coordinate system. As time passes, the phase of P advances from the phase of Q (FIG. 2B). Therefore, when a 180 ° pulse is applied in the y′-axis direction after a time τ has elapsed from the 90 ° pulse, the P and Q nuclear magnetizations rotate 180 ° around the y′-axis, and before the pulse is applied, y ′ The arrangement is symmetric with respect to the axis (FIG. 2C). In this arrangement, since the nuclear magnetization P having a more advanced phase has a phase delayed from Q, both nuclear magnetizations simultaneously reach the y ′ axis at the time when the time τ has passed since then ( FIG. 2 (d)). Since such a relationship holds for the nuclear magnetization of all regions in the sample, all the nuclear magnetization gathers on the y ′ axis at this time, and as a result, a large NMR signal is obtained.

  As described above, in the present embodiment, first, a 90 ° pulse is applied in the x′-axis direction, and then a 180 ° pulse is applied in the y′-axis direction. Therefore, as shown in FIG. The nuclear magnetizations of P and Q are reversed in the x′y ′ plane. The compensation function is satisfactorily exhibited by the reversal of the nuclear magnetization. For example, even if the positions of P and Q are shifted to the upper or lower position of the x′y ′ plane due to the nonuniformity of the magnetic field and the nonuniformity of the excitation pulse intensity irradiated by the RF coil, x′y 'The offset is compensated by reversing the nuclear magnetization in the plane.

(Ii) Step 106 (Measurement of T ₂ relaxation time constant)
The T ₂ relaxation time constant can be accurately measured by using the spin echo method (FIG. 3).
Resonances excited magnetization vector M _-y goes relaxes with time. The time change of the magnetic resonance signal actually observed at this time is relaxed by a spin-lattice relaxation time constant T ₁ and another time constant T ₂ ^* that cannot be expressed only by the spin-spin relaxation T ₂ relaxation time constant. I will do it. This state is shown immediately after the 90 ° excitation pulse as the time variation of the signal intensity at the bottom of FIG. Non-uniformity of the external static magnetic field cause the attenuated signal is attenuated rapidly to be actually observed than the damping curve by the T ₂ relaxation is to make the static magnetic field magnet, nonuniformity of a sample in a magnetic field due to the magnetic properties and shape of the sample This is due to the fact that a uniform magnetic field is not ensured over the entire sample due to its nature.
There is a “spin echo” as a method for correcting a phase shift due to magnetic field inhomogeneity as a sample or device characteristic. This means that after τ time of 90 ° excitation pulse, a 180 ° excitation pulse having twice the excitation pulse intensity is applied and the phase of the magnetization vector M is reversed on the xy plane. is allowed, after 2τ time is a method of obtaining an echo signal to get on and converges the phase T ₂ decay curves on.
Strength S _SE of the echo signal that may occur when using spin echo, in the case of TR >> TE is represented by the following formula (A).

Where ρ is the density distribution of the target nuclide as a function of the position (x, y, z), TR is the 90 ° excitation pulse repetition time (about 100 ms to 10 s), and TE is the echo time (2 t, about 1 ms to 100 ms) ), A is a constant representing the RF coil detection sensitivity and device characteristics such as an amplifier.
An echo signal group riding on T ₂ decay curve can be obtained the T ₂ relaxation time constant from the equation (A).

(Iii) Step 108 (Measurement of water content)
In step 108, the water content is calculated from the relaxation time constant. The amount of water in the sample and the T ₂ relaxation time constant have a positive correlation. As the amount of water increases, the T ₂ relaxation time constant increases. Since this correlation varies depending on the type and form of the sample, it is desirable to prepare a calibration curve for a sample of the same type as the sample to be measured whose moisture concentration is known in advance. That is, it is desirable to measure the relationship between the moisture content and the T ₂ relaxation time constant for a plurality of standard samples whose moisture content is known, and obtain a calibration curve representing this relationship in advance. By referring to the calibration curve thus created, the amount of water in the sample can be calculated from the measured T ₂ relaxation time constant.

Next, calculation of mobility will be described.
(B) Calculation of mobility In order to measure locally the mobility of the specific location of a sample, PGSE (Pulsed-Gradient Spin-Echo) method is used.
After exciting a specific nuclear spin in a liquid molecule by magnetic resonance and applying a pair of gradient magnetic field pulses (pulsed gradient magnetic field) at intervals of several tens of ms, individual nuclei move in a Brownian motion or The phase of the nuclear spin does not converge due to the movement due to diffusion, so that the intensity of the NMR signal decreases. The self-diffusion coefficient of a specific molecular species can be measured by associating the gradient magnetic field pulse changed stepwise with the decrease in the intensity of the NMR signal.
FIG. 4 is a diagram illustrating an example of a PGSE sequence used for measuring the self-diffusion coefficient. In the sequence shown in FIG. 4, a pair of gradient magnetic field pulses Gz having the same intensity as the application time are applied in the z direction to a normal spin echo sequence with a 180 ° excitation pulse as the axis of symmetry, and an NMR signal, for example, a spin echo signal is applied. get. The peak intensity S of the NMR signal depends on the applied pulse gradient magnetic field intensity Gz [gauss / m], the application time d, and the pulse interval Δ, and the self-diffusion coefficient Dz [m ² / s].
ln (S / S ₀ ) = − γ ² DzΔ ² dGz ² (II)

In the above formula (II), S ₀ represents a normal NMR signal intensity when Gz = 0. D, Δ, and Gz represent the pulse width of the gradient magnetic field pulse, the time interval between the pair of gradient magnetic field pulses, and the magnetic field gradient (z direction) of the gradient magnetic field pulse, respectively. Γ represents the gyromagnetic ratio and is a value specific to the nucleus. S ₀ is the peak intensity of the NMR signal when Gz = 0 when no gradient magnetic field is applied, and γ is the gyromagnetic ratio 42.577 × 10 ² [1 / gauss · s] of the hydrogen nucleus ¹ H to be measured.

  FIG. 4 illustrates a sequence when d = 1.5 ms and Δ = 34.5 ms. For example, by applying a magnetic field to the sample in such a pulse sequence, the self-diffusion coefficient Dz can be stably calculated using the peak intensity S of the NMR signal as the NMR signal.

FIG. 5 is a flowchart for locally measuring the mobility of a specific portion of the sample using the PGSE method as described above, and includes the following steps.
First, a sample is placed in a static magnetic field created by a magnet or the like, and a static magnetic field is applied to the sample. In this state, an excitation oscillating magnetic field is applied to the sample via the small RF coil, and an NMR signal corresponding to this is acquired (S202). No gradient magnetic field is applied. Step 202 includes the following steps.
A first step of applying an excitation oscillating magnetic field to the sample according to a predetermined pulse sequence; and
A second step of acquiring an NMR signal corresponding to the pulse sequence of the first step.

Next, a gradient magnetic field is applied to the same region in the sample, and step 204 is executed to acquire an NMR signal. In step 204, the following third step and fourth step are executed once or a plurality of times.
A third step of applying the excitation oscillating magnetic field and gradient magnetic field according to a predetermined pulse sequence; and
A fourth step for acquiring an NMR signal corresponding to the pulse sequence of the third step

  In the first step and the third step, a local magnetic field is applied to a specific portion of the sample using a small RF coil smaller than the sample. In the second step and the fourth step, an NMR signal is acquired from a specific portion of the sample using a small RF coil smaller than the sample.

In addition, in the first step, application of a gradient magnetic field to the sample is executed according to a predetermined pulse sequence, and in the third step, application of a gradient magnetic field having a magnitude different from that of the first step is executed according to a predetermined pulse sequence. You can also.
In FIG. 5, an example in which the gradient magnetic field is not applied is shown in the first step, but a predetermined gradient magnetic field having a magnitude different from that in the third step may be applied in the first step. At this time, for example, it is preferable to set the magnitude of the gradient magnetic field in the first step to a value close to zero.
Subsequently, the self-diffusion coefficient D is calculated from a plurality of NMR signals obtained by changing the gradient of the pulse gradient magnetic field stepwise (S206). In step 206, based on the information of the NMR signal obtained in the second step and the information of the NMR signal obtained in the fourth step, a self-diffusion coefficient D of a specific portion of the sample is calculated.
In addition, after the procedure of step 206, based on the self-diffusion coefficient D calculated in step 206, a parameter indicating other mobility of the protic solvent in the sample may be calculated. Thereafter, the result is output (S208).
By performing such an operation (step 202 to step 208) through each small RF coil, the distribution of the self-diffusion coefficient can be grasped.

Details of each step will be described below.
(I) Step 202 and Step 204 (application of excitation oscillating magnetic field, application of gradient magnetic field and acquisition of NMR signal)
In step 202 and step 204, an excitation oscillating magnetic field and a gradient magnetic field are applied to the sample according to a predetermined sequence. Specifically, as described above, in step 202, the gradient magnetic field is set to zero or a value close to zero, and in step 204, a predetermined gradient magnetic field is applied.

The excitation oscillating magnetic field is a pulse sequence composed of a plurality of pulses, and the gradient magnetic field is a pair of pulse sequences corresponding to the excitation oscillating magnetic field. The pulse sequence is preferably composed of the following (a) to (d).
(A) 90 ° pulse of an oscillating magnetic field for excitation,
(B) A gradient magnetic field pulse that starts after the elapse of the pulse time of (a) and is applied for a fixed time d,
(C) a 180 ° pulse of an oscillating magnetic field for excitation applied after elapse of time τ of the pulse of (a), and
(D) A gradient magnetic field pulse that starts after the elapse of the pulse time of (c) and is applied for a predetermined time d.
Referring to FIG. 4, the time when the application of the gradient magnetic field pulse of (b) is completed and the time when the application of the gradient magnetic field pulse of (d) is started are the 180 ° pulses (pulses) of (c). However, there is a width of 120 microseconds, and the distance of 60 microseconds at the center is considered as the axis of symmetry, and is separated by an equal time ((34.5 ms-1.5 ms) /2=16.5 ms). Furthermore, the gradient magnetic field pulse application time d in (b) and the gradient magnetic field pulse application time d in (d) are both made equal (d = 1.5 ms).

Then, an NMR signal corresponding to the pulse sequence is measured. The peak intensity S of the NMR signal is measured by a spin echo method.
Specifically, as shown in FIG. 4, the peak intensity S of the echo signal that appears at 2τ time is measured. The peak intensity S may be not only the NMR signal intensity for 2τ hours, but also the average value of the NMR signal intensity measured in the surrounding time. By this method, it is possible to reduce variations in measured values caused by noise included in the NMR signal.

  In this embodiment, the self-diffusion coefficient D of protons in the sample is calculated by applying a gradient magnetic field stepwise and detecting the degree of decrease in the NMR signal corresponding to the case where the magnetic field gradient is increased.

(Ii) Step 206 (Measurement of self-diffusion coefficient D)
In step 206, the self-diffusion coefficient D is obtained from the peak intensity of the NMR signal. The proton self-diffusion coefficient D is expressed by the above-described formula (II) using the peak intensity S of the NMR signal acquired by the PGSE method.
From the peak intensity S ₀ of the NMR signal when the gradient magnetic field G is not applied and the peak intensity S of the NMR signal when the gradient magnetic field G is applied, the self of protons in the sample is obtained using the above formula (II). A diffusion coefficient D can be obtained. For example, measurement is performed by changing the magnitude of the same gradient magnetic field G in the sample, and by plotting the relationship between ln (S / S ₀ ) and −γ ² DΔ ² dG ² , the self-diffusion coefficient is calculated from the gradient of the plot. D can be determined.

FIG. 6 is a diagram illustrating a measurement example of the self-diffusion coefficient D. Here, the amount of decrease in the NMR signal intensity when the magnitude of the gradient magnetic field was changed and the peak intensity of the NMR signal of distilled water was measured was measured. The measurement temperature was 25 ° C. From formula (II), the self-diffusion coefficient D can be obtained from the slope of the straight line ln (S / S ₀ ) −γ ² DΔ ² dG ² .

Based on the above principle, in order to accurately measure the moisture content distribution and mobility (in this embodiment, the self-diffusion coefficient is measured as mobility), the nuclide to be measured (in this embodiment, It is important to obtain a nuclear magnetic resonance signal in accordance with the resonance frequency of the hydrogen nucleus ¹ H). The resonance frequency of the nuclide to be measured changes depending on the strength of the static magnetic field. The static magnetic field strength is not completely uniform and has a distribution, and as shown in FIGS. 31 and 33, the static magnetic field strength varies depending on the installation position of the small RF coil.
In addition, if the static magnetic field is applied to the sample by a magnet such as a permanent magnet that is susceptible to temperature changes, the strength of the static magnetic field increases or decreases due to the temperature change of the magnets, and the resonance frequency also increases or decreases accordingly. (See FIGS. 35 and 37).
That is, according to the distribution of the static magnetic field strength, it is necessary to generate an RF pulse having a different frequency for each installation position of the small RF coil, and at the same time, in accordance with the increase / decrease of the static magnetic field strength accompanying the temperature change of the magnet, It is necessary to set the frequency of the pulse.
In the present embodiment, an RF pulse having a frequency corresponding to the resonance frequency of nuclear magnetization at the installation position of each small RF coil of the sample to which a static magnetic field is applied is applied to the sample from each small RF coil. Thereby, the measuring apparatus which can grasp | ascertain exact moisture content distribution and mobility distribution is implement | achieved.

(First embodiment)
FIG. 7 is a diagram illustrating a schematic configuration of the measuring apparatus 1 according to the present embodiment. Each component of the measuring apparatus 1 is realized by an arbitrary combination of hardware and software, centering on a CPU, a memory, a program that implements the components shown in FIG. It will be understood by those skilled in the art that there are various modifications to the implementation method and apparatus.
A part of FIG. 7 and FIGS. 9 to 11, 14, 17, 18, 22 to 27 show functional unit blocks instead of hardware unit configurations.
In all the drawings, similar constituent elements are denoted by the same reference numerals, and description thereof will be omitted as appropriate.

An outline of the measuring apparatus 1 shown in FIG. 7 will be described.
The measuring apparatus 1 uses the nuclear magnetic resonance method to distribute the behavior of the protic solvent (water molecule) in the sample 115 (here, the behavior of the protic solvent (water content, mobility, and movement amount)). (Spatial distribution).

The measuring apparatus 1 mainly has the following configuration.
A static magnetic field application unit (magnet 113) that applies a static magnetic field to the sample 115
A plurality of small RF coils 114 smaller than the sample 115 that apply an oscillating magnetic field for excitation to the sample 115 and acquire a nuclear magnetic resonance signal generated in the sample 115.
A calculation unit 130 that calculates the behavior of the protic solvent based on the nuclear magnetic resonance signal acquired by the small RF coil 114
An output unit 135 that outputs the behavior of the protic solvent (water molecule) calculated by the calculation unit 130
An RF pulse generator that generates an RF pulse that generates an oscillating magnetic field for excitation in each small RF coil 114

Here, the RF pulse generator is
An oscillator 102 that oscillates a signal of a predetermined frequency
A setting unit 200 that sets the frequency of the oscillator 102
-It has the modulator 104 (refer FIG. 9) which modulates the signal which the oscillator 102 oscillated, and produces | generates RF pulse.
In the setting unit 200, the frequency of the oscillator 102 is tuned to the resonance frequency (magnetic resonance frequency) of the nuclear magnetization at the installation position of each small RF coil 114 when a static magnetic field is applied to the sample 115 by the static magnetic field applying unit 113. Thus, the frequency of the oscillator 102 is set.
The modulator 104 modulates the signal oscillated from the oscillator 102 whose frequency is set by the setting unit 200 and generates an RF pulse having the frequency set by the setting unit 200.

Below, the structure of the measuring apparatus 1 is demonstrated in detail.
First, the sample 115 and the device configuration around the sample 115 will be described.
In addition to the above-described small RF coil 114, magnet 113, oscillator 102, and setting unit 200, the measuring apparatus 1 includes a G coil (gradient magnetic field applying unit) 151, a sensor control unit 103, an A / D converter 118, and mode switching. A control unit 169, a current driving power source 159, and the like are included.

  The sample 115 has a configuration in which a protic solvent (water in this embodiment) is held in a sample to be measured. The sample constituting the sample 115 can be in various forms such as a film, a solid such as a massive substance, a liquid, a gel such as a jelly-like substance such as an agar gel. In the case of a film-like substance, the measurement result of the mobility of the local protic solvent and the measurement result of the amount of the protic solvent can be stably obtained. In particular, when a film having a property of retaining moisture in the film, such as a solid electrolyte film, is used as a sample, the measurement result can be obtained more stably.

The magnet 113 is a permanent magnet that applies a static magnetic field to the entire sample 115. The excitation oscillating magnetic field is applied to the sample 115 in a state where the static magnetic field is applied, and the moisture content is measured.
Further, an excitation oscillating magnetic field and a gradient magnetic field pulse are applied to the sample 115 in a state where a static magnetic field is applied to the sample 115, and the self-diffusion coefficient is measured.

The small RF coil 114 applies an excitation oscillating magnetic field to a specific portion of the sample 115.
Further, an NMR signal corresponding to the excitation oscillating magnetic field and an NMR signal corresponding to the gradient magnetic field are acquired.
In the present embodiment, a plurality of small RF coils 114 are provided, and are arranged at predetermined intervals along the surface of the sample 115 as shown in FIG.
The small RF coil 114 is preferably ½ or less of the size of the entire sample, and more preferably 1/10 or less. By setting it as such a size, it becomes possible to measure the local mobility of the water molecule in the sample 115 and the water content accurately in a short time. The size of the sample can be, for example, a projected area when the sample is placed, and the exclusive area of the small RF coil 114 is preferably ½ or less of the projected area, more preferably 1 By setting it to / 10 or less, accurate measurement can be performed in a short time. The size of the small RF coil 114 is preferably, for example, 10 mm or less in diameter.

  As the small RF coil 114, for example, a planar spiral coil can be used, and the measurement region can be limited by using such a planar coil. The measurement area of the spiral coil (small RF coil) has a width about the diameter of the coil and a depth about the coil radius.

The oscillating magnetic field (exciting oscillating magnetic field) applied by the small RF coil 114 is generated by the cooperation of the setting unit 200, the oscillator 102, the pulse control unit 108 (see FIG. 18), the sensor control unit 103, and the small RF coil 114. The
An NMR signal is emitted with respect to the oscillating magnetic field generated by such cooperation and applied by the small RF coil 114, and the small RF coil 114 detects the emitted NMR signal. This NMR signal is sent to the A / D converter 118 via the sensor control unit 103. The A / D converter 118 A / D-converts the NMR signal and sends it to the calculation unit 130.

A plurality of sensor control units 103 are provided corresponding to each small RF coil 114. As shown in FIG. 9, each sensor control unit 103 includes a modulator 104, an RF amplifier 106, a switch unit 161, a preamplifier 112, A phase detector 110 is included.
In the present embodiment, an RF pulse generation unit that generates an RF pulse that generates an excitation oscillating magnetic field in the small RF coil 114 includes a setting unit 200, an oscillator 102, a modulator 104, and an RF amplifier 106.
On the other hand, the NMR signal detection unit that detects the NMR signal acquired by the small RF coil 114 and sends the NMR signal to the calculation unit 130 includes the preamplifier 112, the phase detector 110, the A / D converter 118, and the oscillator 102. Consists of including.
The phase detector 110 detects a nuclear magnetic resonance signal based on the frequency of the oscillator 102.

As described above, the RF excitation pulse generation unit modulates the signal from the oscillator 102 that oscillates a signal having a predetermined frequency, the setting unit 200 that sets the frequency of the oscillator 102, and the RF signal by modulating the signal from the oscillator 102. The RF excitation pulse is generated to generate an oscillating magnetic field for excitation in the small RF coil 114.
A signal having a frequency set by the setting unit 200 is oscillated from the oscillator 102. Then, this signal is modulated by the modulator 104 and becomes a pulse shape. The generated RF pulse is amplified by the RF amplifier 106 and then transmitted to the small RF coil 114. The small RF coil 114 applies this RF pulse to a specific location of the sample 115 placed on the sample placement table 116.

Here, the configuration of the setting unit 200 will be described.
As illustrated in FIG. 10, the setting unit 200 includes a storage unit (first storage unit) 201 and a calculation unit 202.
The storage unit 201 stores the temporal change calculated by the temporal change calculation unit 204 and the like.
As shown in FIG. 11, the calculation unit 202 includes a frequency calculation unit 203, a temporal change calculation unit 204, an estimation unit 205, and a temporary frequency setting unit 209.
The frequency calculation unit 203 calculates the resonance frequency of nuclear magnetization at the installation position of the small RF coil 114 of the sample 115 to which a static magnetic field is applied.
When a signal having a predetermined frequency (temporary frequency) is oscillated from the oscillator 102 and an excitation oscillating magnetic field is applied to the sample 115 from the small RF coil 114, the small RF coil 114 acquires a nuclear magnetic resonance signal. .
The frequency calculation unit 203 acquires the nuclear magnetic resonance signal acquired by the small RF coil 114 via the phase detector 110.
When there is a difference between the frequency of the oscillator 102 and the magnetic resonance frequency (resonance frequency of nuclear magnetization at the installation position of one small RF coil 114) determined by the static magnetic field intensity at the installation position of one small RF coil 114 Shows a frequency difference in the acquired magnetic resonance signal. This frequency difference is seen as if the waveform representing the components of the imaginary part and the real part crosses the horizontal axis that is the time axis and rotates or vibrates.
Therefore, the frequency at which the oscillator 102 oscillates from the state in which the waveform representing the imaginary part and real part of the magnetic resonance signal observed after detection intersects the time axis (the frequency of the imaginary part or real part of the magnetic resonance signal). And the difference between the resonance frequency of the nuclear magnetization at the installation position of one small RF coil 114 can be calculated.
Thereby, the resonance frequency (true resonance frequency) of nuclear magnetization at the installation position of the small RF coil 114 of the sample 115 can be calculated.

This will be described in more detail below. First, as shown in FIG. 12, the acquired nuclear magnetic resonance signals are aligned with the original phases of the imaginary part and the real part. That is, the phase angle is corrected so that the real part is an even function with respect to the origin and the imaginary part is an odd function with respect to the origin. The phase angle is adjusted almost accurately by the receiving hardware in advance, but is fine-tuned by software for higher accuracy. FIG. 12 shows three waveforms whose phase angles are adjusted symmetrically by software. The top waveform in FIG. 12 is the real part waveform of the nuclear magnetic resonance signal, the central waveform in FIG. 12 is the imaginary part waveform of the nuclear magnetic resonance signal, and the bottom waveform in FIG. It is a signal waveform of the absolute value of a magnetic resonance signal.
In FIG. 12, the horizontal axis represents time, and the vertical axis represents the intensity of the nuclear magnetic resonance signal. The slope θ of the waveform of the imaginary part at the peak position of the waveform of the nuclear magnetic resonance signal is calculated.
Specifically, tan θ is calculated from Vre of the real part, that is, Vabs, Δt of the imaginary part, and ΔV,
The angle θ is obtained using the inverse function.
tanθ = imaginary part / real part = sinθ / cosθ = (ΔV / Δt) / ΔVbas
Inverse function: θ = tan ^-1 ((ΔV / Δt) / ΔVbas)
θ = ω × t = 2πf × t (t is time, ω = 2πf)
So
f = θ / (2π × t)
Then, from the value of the angle θ, it is possible to detect the frequency f (that is, the frequency f of the imaginary part) that the sin wave (imaginary part of the nuclear magnetic resonance signal) intersects the time axis for a certain time (1 second). it can. The frequency of the imaginary part corresponds to the difference between the frequency (temporary frequency) set by the oscillator 102 and the resonance frequency (true resonance frequency) of nuclear magnetization. Based on this difference, the resonance frequency (true co-frequency) of nuclear magnetization can be calculated.
As shown in FIG. 13, the resonance frequency (true resonance frequency) of the nuclear magnetization calculated by the frequency calculation unit 203 is associated with the number of the small RF coil 114 and stored together with the time when the resonance frequency of the nuclear magnetization is calculated. Stored in the unit 201.

As shown in FIG. 14, the temporal change calculation unit 204 includes a frequency change rate calculation unit 207 and a temperature difference calculation unit 208.
The frequency change rate calculation unit 207 acquires the resonance frequency of the nuclear magnetization at different times calculated by the frequency calculation unit 203, and, for example, in one second, the resonance of the nuclear magnetization during a certain time (t2-t1). Calculate how much the frequency changes (change over time).
The calculated frequency change speed is stored in the storage unit 201 (see FIG. 13).
Here, when the speed of change in the resonance frequency of the nuclear magnetization at each installation position of the plurality of small RF coils 114 can be regarded as substantially the same, the frequency change rate calculation unit 207 determines that the single small RF coil 114 has the same speed. It is only necessary to calculate the change in the resonance frequency of the nuclear magnetization at the installation position of.
In addition, when the change speed of the resonance frequency of nuclear magnetization differs greatly at each installation position of each small RF coil 114, the temporal change of the resonance frequency of nuclear magnetization is calculated at each installation position of each small RF coil 114. do it.
In this embodiment, since the speed of change in the resonance frequency of nuclear magnetization at each installation position of a plurality of small RF coils 114 can be considered to be substantially the same, the frequency change rate calculation unit 207 is configured to Only the change in the resonance frequency of the nuclear magnetization at the installation position is calculated.

  The temperature difference calculation unit 208 is connected to the temperature sensor, detects the difference between the surface temperature of the magnet 113 and the room temperature of the room in which the measuring apparatus 1 is installed, and stores the difference in the storage unit 201.

  The estimation unit 205 includes the frequency change rate stored in the storage unit 201, the temperature difference between the temperature of the magnet 113 and the room temperature, and the nuclear magnetization of the position of each small RF coil 114 at a predetermined time calculated by the frequency calculation unit 203. The resonance frequency of the nuclear magnetization at the installation position of each small RF coil 114 at the time of measurement of the moisture content or the like is estimated from the resonance frequency of. Then, the frequency of the oscillator 102 is set to the resonance frequency estimated by the estimation unit 205, and the resonance frequency of the nuclear magnetization at the installation position of each small RF coil 114 at the measurement time and the frequency of the oscillator 102 are tuned.

For example, when the temperature of the magnet 113 is high, the room temperature is low, and the temperature difference is large, the fluctuation speed of the resonance frequency is large, and the direction of the fluctuation is the direction in which the resonance frequency is “increased” (high frequency side).
In addition, when the temperature of the magnet 113 is low, the room temperature is high, and the temperature difference is large, the fluctuation speed of the resonance frequency is large, and the direction of the fluctuation moves in a direction in which the resonance frequency “lowers” (low frequency). .

Thus, the change rate of the resonance frequency greatly depends on the temperature difference between the magnet 113 and room temperature. Therefore, the estimation unit 205 estimates the resonance frequency of the nuclear magnetization at the installation position of the small RF coil 114 at the measurement time in consideration of the frequency change rate stored in the storage unit 201 and the relationship between the temperature of the magnet 113 and room temperature. is there.
In addition, in the estimation unit 205, the position of the small RF coil 114 at the measurement time in consideration of the frequency change rate, the relationship between the magnet 113 temperature and the room temperature, the state of the airflow around the magnet 113, the heat transfer coefficient, and the like. The resonance frequency of the nuclear magnetization may be estimated.

  The application of the excitation oscillating magnetic field and the acquisition of the NMR signal have been described above. However, the application of the excitation oscillating magnetic field and the acquisition of the NMR signal can be realized by an LC circuit including a small RF coil. FIG. 15 is a diagram illustrating an example of such an LC circuit. The coil portion (inductance portion) of the resonance circuit is a small RF coil having a diameter of 2.0 mm. In the nuclear magnetic resonance (NMR) method, the atomic number density and the spin relaxation time constant can be measured by detecting the movement of nuclear magnetization as an NMR signal by the spin resonance phenomenon of a nucleus placed in a magnetic field. The spin resonance frequency in a magnetic field of 1 Tesla is about 43 MHz, and an LC resonance circuit as shown in FIG. 15 is used to selectively detect the frequency band with high sensitivity.

Here, the excitation oscillating magnetic field applied to the sample 115 by the small RF coil 114 is, for example,
(A) a 90 ° pulse, and
(B) A pulse sequence composed of 180 ° pulses applied after the time τ of the pulse in (a) has elapsed.

Here, even in a pulse sequence in which the 90 ° pulse is in the first phase and the 180 ° pulse is in the second phase shifted by 90 ° from the first phase, the peak intensity of the NMR signal based on the spin-spin and the sample 115 The correlation between the self-diffusion coefficient of water and the correlation between the T ₂ relaxation time constant and the amount of water in the sample 115 can also be acquired.

  In the case where the small RF coil 114 is used, it may be difficult to adjust the excitation pulse intensity of the above (a) and (b). For example, in the region to be measured, that is, the region surrounded by the small RF coil 114, a difference occurs in the excitation method between the central portion and the peripheral portion, so that the entire excitation angle is uniform. That is, it may be difficult to excite so that the intensity ratio of the oscillating magnetic field for excitation in (a) and (b) is constant. If the excitation angle ratio in (a) and (b) varies, it becomes difficult to accurately measure the moisture content and the self-diffusion coefficient.

  Therefore, in such a case, in addition to the above pulse sequence, the pulse control unit 108 adds another sequence in which a step of applying a 180 ° pulse is added at a time τ before the 90 ° pulse (a). Make it run. Then, by comparing the behavior of the NMR signal (echo signal) obtained by these two sequences (inversion of the phase waveform obtained by the phase detector, whether the signal intensity is comparable, etc.), a 90 ° pulse It can be determined whether the excitation pulse intensities of (a) and 180 ° pulse (b) are accurate. As a result, even when the excitation pulse intensity is deviated due to an abnormality of the apparatus, the abnormality can be detected at a stage before the measurement is performed, and the measurement value can be made more accurate.

Next, the configuration of the switch unit 161 will be described.
As described above, the switch unit 161 is provided in the branching unit that connects the small RF coil 114, the RF excitation pulse generation unit, and the NMR signal detection unit.

The switch unit 161 is
A first state in which the small RF coil 114 and the RF excitation pulse generator (RF amplifier 106) are connected; and
It has a function of switching the second state in which the small RF coil 114 and the NMR signal detector (phase detector 110) are connected.

  The switch unit 161 serves as such a “transmission / reception switching switch”. The role is to transmit the excitation pulse amplified by RF power-amp to the small RF coil 114 to separate the preamplifier 112 of the receiving system and protect it from a large voltage, and to receive the NMR signal after excitation. In other words, the noise generated by the large amplification transistor leaking from the RF amplifier 106 is blocked from being transmitted to the preamplifier 112 of the receiving system. When measurement is performed using the small RF coil 114, a weak signal is handled, so the switch unit 161 is necessary for the following reason. On the other hand, in a large measurement system that does not use the small RF coil 114, the use of a “cross diode” can sufficiently cope. The cross diode is a diode that is turned on when a voltage equal to or higher than a predetermined value is applied and is turned off when the voltage is lower than the predetermined value.

  The switch unit 161 can employ various configurations. FIG. 16 is a circuit diagram showing an example of the configuration of the switch unit 161.

As shown in FIG. 8, the G coil 151 is disposed so that a gradient magnetic field can be applied to the sample 115. Two G coils 151 are arranged with respect to one small RF coil 114, and are opposed to each other with the small RF coil 114 interposed therebetween.
Various shapes can be adopted for the G coil 151, but a flat coil is used in this embodiment. In this embodiment, the G coil 151 has a half-moon shape.
The G coil 151 is arranged in parallel to the surface of the sample 115.
The G coil 151 is disposed above the small RF coil 114. Thereby, a gradient magnetic field having a magnetic field gradient in the y-axis direction can be formed on the central axis of the small RF coil 114.
A shielding shield (not shown) is provided between the small RF coil 114 and one G coil 151 and between the small RF coil 114 and the other G coil 151. This shielding shield prevents noise from the G coil 151 from affecting the small RF coil 114. The shielding shield has a thickness that prevents the passage of noise and allows a magnetic field to pass.
Note that only the small RF coil 114 is brought into contact with the sample 115 when measuring the moisture content and the self-diffusion coefficient.

The setting of the frequency of the oscillator 102 by the setting unit 200, the application of a high frequency pulse to the small RF coil 114, and the supply of the pulse current to the G coil 151 via the current driving power source 159 include the mode switching control unit shown in FIG. 169. As shown in FIG. 17, mode switching control unit 169 includes a mode selection unit 169A and a control unit 169B.
The mode selection unit 169A receives a request input by the worker, and selects a mode corresponding to the received request from a plurality of modes.
In this embodiment, a resonance frequency acquisition mode for acquiring the resonance frequency of nuclear magnetization at the installation position of each small RF coil 114, a dummy mode for receiving only an excitation oscillating magnetic field without receiving an NMR signal, and in the sample 115 One of the first measurement mode for measuring the moisture content at a specific location of the sample and the second measurement mode for measuring the mobility (self-diffusion coefficient) of water molecules at the specific location in the sample 115 is selected. .

FIG. 18 is a diagram illustrating a configuration example of the control unit 169B. The control unit 169B controls the operation of the small RF coil 114 and a G coil 151 to be described later. When in the mode for measuring the moisture content, the excitation RF magnetic field is applied to the sample 115 by the small RF coil 114. At the same time, control is performed so that the nuclear magnetic resonance signal corresponding to the excitation oscillating magnetic field is acquired by the small RF coil 114.
When in the mode for measuring the self-diffusion coefficient, an excitation oscillating magnetic field is applied to the sample 115 by a small RF coil, and a gradient magnetic field is applied by the G coil 151 to be generated corresponding to these magnetic fields. Control is performed so that the nuclear magnetic resonance signal is acquired by the small RF coil 114.
Specifically, the control unit 169B includes a pulse control unit 108 that controls the operation of the modulator 104 and a gradient magnetic field control unit 171 that controls the operation of the current driving power source 159.

A sequence table 127 is connected to the control unit 169B. In this sequence table 127, the sequence data of the radio frequency pulse when measuring the moisture content, the radio frequency pulse and the gradient magnetic field when measuring the self-diffusion coefficient are stored. Sequence data for determining a sequence of pulse currents to be generated and high-frequency pulse sequence data for dummy excitation described later are stored. That is, the first timing diagram in which the time at which a high frequency pulse is generated when measuring the amount of water and the interval between them, and the pulse current for the high frequency pulse and gradient magnetic field when measuring the self-diffusion coefficient are shown. A second timing diagram in which the generation time and the interval are set is stored, and a third timing diagram in which the time at which the high-frequency pulse is generated during dummy excitation and the interval is set is stored.
The sequence table 127 stores the intensity of the high frequency pulse applied based on the first timing diagram. The sequence table 127 also stores the high-frequency pulse applied based on the second timing diagram and the intensity of the pulse current for the gradient magnetic field. Further, the intensity of the high frequency pulse applied based on the third timing diagram is also stored in the sequence table 127.
In addition, a timer unit 128 is connected to the control unit 169B.

  Such a control unit 169B generates a high-frequency pulse and a pulse current for a gradient magnetic field based on the sequence data acquired from the sequence table 127 and the measurement time in the time measuring unit 128.

Here, the switching operation of the measurement mode by the mode switching control unit 169 will be described.
In the present embodiment, after obtaining the resonance frequency of nuclear magnetization at the installation position of each small RF coil 114, dummy excitation is performed in which only the excitation oscillating magnetic field is applied without receiving an NMR signal. Thereafter, the setting unit 200 sets the frequency of the oscillator 102 in synchronization with the resonance frequency of the nuclear magnetization at the installation position of each small RF coil 114, and measures the moisture content and the self-diffusion coefficient.

That is, as shown in FIG. 19, the measurement method of this embodiment is
A step of applying a static magnetic field to the sample 115 from the static magnetic field application unit (magnet 113) (step 30).
A step of setting the frequency of the oscillator 102 by tuning the frequency of the oscillator 102 by the setting unit 200 to the resonance frequency of the nuclear magnetization at the installation position of each small RF coil 114 of the sample 115 to which a static magnetic field is applied. (Step 31)
The signal having the frequency set in step 30 is oscillated from the oscillator 102, the signal from the oscillator 102 is modulated by the modulator 104 to generate an RF pulse, and for each small RF coil 114, each small RF coil A step of transmitting an RF pulse having a frequency corresponding to the resonance frequency of the nuclear magnetization at the installation position 114 (step 32)
A step of applying an oscillating magnetic field for excitation from each small RF coil 114 to the sample 115 (step 33)
A step of acquiring a nuclear magnetic resonance signal generated in the sample 115 via each small RF coil 114 (step 34).
A step of calculating the behavior (moisture content, self-diffusion coefficient) of the protic solvent in the sample 115 by the calculation unit 130 based on the acquired nuclear magnetic resonance signal (step 35).
A step of determining whether or not both the moisture content and the self-diffusion coefficient have been calculated in each small RF coil 114 (step 36)
A step of determining whether or not measurement has been completed for all small RF coils (step 37).
including.

Then, the step (step 31) of setting the frequency of the oscillator 102 in synchronization with the resonance frequency of the nuclear magnetization at the installation position of each small RF coil 114 is as shown in FIG.
A step of acquiring a time-dependent change in the resonance frequency of nuclear magnetization at the installation position of one small RF coil 114 of the sample 115 to which a static magnetic field is applied (step 311).
A step of calculating the resonance frequency of nuclear magnetization at the installation position of each small RF coil 114 of the sample 115 to which a static magnetic field is applied at a predetermined time (step 312)
A step of performing dummy excitation in which only an excitation oscillating magnetic field is applied without receiving an NMR signal (step 313)
Each time at the measurement time of the behavior of the protic solvent (water content, self-diffusion coefficient) from the time-dependent change in the resonance frequency of the nuclear magnetization and the resonance frequency of the nuclear magnetization at the installation position of each small RF coil 114 at a predetermined time Step of estimating the resonance frequency of nuclear magnetization at the installation position of the small RF coil 114 (step 314)
It is comprised including.

First, the operator inputs a request for selecting a resonance frequency acquisition mode for acquiring the resonance frequency of nuclear magnetization to the measurement apparatus 1. The operation signal receiving unit 129 receives this request.
When the operation signal receiving unit 129 receives the request, application of a static magnetic field to the sample 115 by the magnet 113 is started (step 30).
The operation signal receiving unit 129 sends the received request to the mode switching control unit 169.
This request is sent to the mode selection unit 169A of the mode switching control unit 169. The mode selection unit 169A selects a mode according to the content of the request from a plurality of modes.
Here, since the request is a request to select the resonance frequency acquisition mode, the mode selection unit 169A selects the resonance frequency acquisition mode and generates specific information for specifying the resonance frequency acquisition mode. Then, this specific information is sent to the setting unit 200.
The setting unit 200 determines the content of the received specific information. When the setting unit 200 determines that the specific information specifies the resonance frequency acquisition mode, the provisional frequency setting unit 209 sets the frequency of the oscillator 102 appropriately, A signal with a temporary frequency is oscillated.
The temporary frequency set by the temporary frequency setting unit 209 is associated with the number of one small RF coil 114 (installation position of the small RF coil 114) to which the excitation oscillating magnetic field having the temporary frequency is applied. Is stored in the storage unit 201 together with the time at which the frequency is set (see FIG. 13).

  By oscillating a signal of a temporary frequency from the oscillator 102, from one small RF coil 114 (for example, a coil disposed at the center of the plurality of small RF coils 114) among the plurality of small RF coils 114, An excitation oscillating magnetic field is applied to the sample 115. Then, a nuclear magnetic resonance signal is acquired by one small RF coil 114. The nuclear magnetic resonance signal acquired by one small RF coil 114 is sent to the phase detector 110, and then the frequency calculation unit 203 is detected based on the temporary frequency via the phase detector 110. Acquire nuclear magnetic resonance signals.

The frequency calculation unit 203 reads the temporary frequency set by the temporary frequency setting unit 209 from the storage unit 201. Then, the frequency calculation unit 203 installs the small RF coil 114 of the sample 115 based on the nuclear magnetic resonance signal detected based on the temporary frequency and the temporary frequency set by the temporary frequency setting unit 209. The resonance frequency (true resonance frequency) of the nuclear magnetization at the position is calculated.
The true resonance frequency calculated by the frequency calculation unit 203 is associated with the number of one small RF coil 114 (installation position of the small RF coil 114) and stored in the storage unit 201 together with the time when the true resonance frequency was calculated. (See FIG. 13).

Next, after a predetermined time has elapsed, the temporary frequency setting unit 209 again sets the frequency of the oscillator 102 appropriately, and the signal of the temporary frequency is oscillated from the oscillator 102. Then, the true resonance frequency after a predetermined time has elapsed is calculated by the frequency calculation unit 203 by the same method as described above. The calculated true resonance frequency is associated with the number of the small RF coil 114 and is stored in the storage unit 201 together with the time when the true resonance frequency is calculated (see FIG. 13).
Here, while the true resonance frequency is calculated by the frequency calculation unit 203, the difference between the surface temperature of the magnet 113 and the room temperature of the room in which the measuring apparatus 1 is installed is detected by the temperature difference calculation unit 208. To do. The detected temperature is stored in the storage unit 201.

When the true resonance frequency values at different times (t 1, t 2) are stored in the storage unit 201, the frequency change rate calculation unit 207 displays the true value of the nuclear magnetization at the installation position of one small RF coil 114 at different times. Is calculated from the storage unit 201, and how much the resonance frequency of nuclear magnetization changes (time-dependent change) in one second, for example, during a certain time (t2-t1) (step 311).
The calculated frequency change speed is stored in the storage unit 201 (see FIG. 13).

When the frequency change speed is stored in the storage unit 201, the temporary frequency setting unit 209 of the setting unit 200 sets the frequency of the oscillator 102 to a temporary frequency, and the signal of the temporary frequency is oscillated from the oscillator 102. The temporary frequency set by the temporary frequency setting unit 209 is associated with the number of another small RF coil 114 (installation position of the small RF coil 114) to which the excitation oscillating magnetic field having the temporary frequency is applied. Is stored in the storage unit 201 together with the time when the frequency is set.
Then, an excitation oscillating magnetic field is applied to the sample 115 from another small RF coil 114 different from the one small RF coil 114, and a nuclear magnetic resonance signal is acquired by the other small RF coil 114. Thereafter, the frequency calculation unit 203 acquires the nuclear magnetic resonance signal detected by the phase detector 110 based on the temporary frequency.
Based on the acquired nuclear magnetic resonance signal and the provisional frequency stored in the storage unit 201, the frequency calculation unit 203 calculates the resonance frequency (true true) of the nuclear magnetization at the installation position of the other small RF coil 114 of the sample 115. Resonance frequency) is calculated. The true resonance frequency calculated by the frequency calculation unit 203 is associated with the number of the other small RF coil 114 (position of the small RF coil 114), and is stored in the storage unit 201 together with the time when the true resonance frequency is calculated. (See FIG. 21).
Such an operation is repeated, and the true resonance frequency of the nuclear magnetization at the installation positions of all the small RF coils 114 and the time when the true resonance frequency is calculated are stored in the storage unit 201 (see FIG. 21) (step 312).

Next, the operator inputs a request to the measuring apparatus 1 to select a dummy mode in which only the excitation oscillating magnetic field is applied without receiving the NMR signal. The operation signal receiving unit 129 receives this request.
The request received by the operation signal receiving unit 129 is sent to the mode switching control unit 169.
This request is sent to the mode selection unit 169A of the mode switching control unit 169. The mode selection unit 169A selects a mode (dummy mode) according to the content of the request from among a plurality of modes. Then, mode selection unit 169A sends information specifying the dummy mode to setting unit 200 and control unit 169B.
The setting unit 200 determines the content of the received specific information, and when it is determined that the specific information specifies a dummy mode, sets the frequency of the oscillator 102 appropriately. Then, a signal is oscillated from the oscillator 102.
On the other hand, the control unit 169B reads sequence data from the sequence table 127. Then, the pulse control unit 108 of the control unit 169B controls the operation of the modulator 104, and applies an excitation oscillating magnetic field to the sample 115 in a predetermined pulse sequence (step 313).

By performing such dummy excitation, measurement reproducibility and reliability can be improved.
When nuclear magnetization in a thermal equilibrium state is excited by a 90 ° excitation pulse, the nuclear magnetization is excited and returns to a thermal equilibrium state with time t (s) with a time constant T1 (s) called T1 relaxation time constant. If the static magnetic field direction component of the nuclear magnetization is represented by Mz and the magnitude of the nuclear magnetization in a thermal equilibrium state is represented by M0, the state of relaxation of the nuclear magnetization is expressed by the following equation.
Mz / M0 = 1-exp (-t / T1) ... Formula (B)
Here, although the value of T1 of the T1 relaxation time constant varies depending on the sample, it is about 2 to 3 seconds for pure water and about 100 ms to 1 second for the solid polymer electrolyte membrane.
In this formula (B), in order for the static magnetic field direction component Mz of the nuclear magnetization to recover almost to M0 after being excited by 90 °, it takes five times T1 after the excitation. When a 90 ° excitation pulse is irradiated for a time ts shorter than 5 × T1, the static magnetic field direction component of the nuclear magnetization becomes Mz (ts) smaller than M0, and the nuclear magnetization is excited more than when excited by M0 in the thermal equilibrium state. This also reduces the nuclear magnetic resonance signal emitted. After that, if the excitation is again performed in a short time ts, the emitted nuclear magnetic resonance signal becomes smaller.
It seems that the nuclear magnetic resonance signal becomes zero after multiple excitations, but in reality, the nuclear magnetization that cannot be recovered (nuclear magnetization on the way to return to thermal equilibrium) is not excited by the 90 ° excitation pulse, so it recovers. The static magnetic field direction component of the nuclear magnetization becomes constant after a plurality of excitations. This is called saturation. When such a state is reached, the intensity of the magnetic resonance signal becomes substantially constant, and a highly reproducible and reliable measurement is possible.
Thus, in the case of irradiating the 90 ° excitation pulse at a time interval shorter than 5 times the T1 relaxation time constant, in order to make the magnetic resonance signal constant, a plurality of times are measured before the measurement of the moisture content or the like. An excitation pulse (this is called a dummy pulse) is irradiated. The number of times of irradiation often varies depending on the sample, and it is about 2 to 8 times in normal measurement.

Next, when the operator inputs a request to perform both moisture measurement and self-diffusion coefficient measurement, the operation signal accepting unit 129 connected to the mode switching control unit 169 accepts the request. Then, the operation signal receiving unit 129 sends this request to the mode switching control unit 169.
The mode selection unit 169A selects a measurement mode for measuring the moisture content from among a plurality of modes, and sends information for specifying the selected measurement mode to the control unit 169B, the data reception unit 131, and the setting unit 200.
The data receiving unit 131 sends specific information for specifying the measurement mode to the calculation unit 130. The calculation unit 130 performs a corresponding calculation process based on the measurement mode specifying information. If the measurement mode identification information indicates the first measurement mode for measuring the moisture content, the measurement data is sent to the moisture content calculator 132, and the measurement mode identification information indicates the second measurement mode for measuring the self-diffusion coefficient. If so, the measurement data is sent to the mobility calculation unit 133, and a predetermined process is executed in each calculation unit.

On the other hand, the setting unit 200 that has received the measurement mode specifying information determines the content of the received specifying information. When the setting unit 200 determines that the specific information specifies a measurement mode for measuring the moisture content, the nuclear magnetization at the installation position of the small RF coil 114 to which the excitation oscillating magnetic field is first applied is determined. Is estimated (step 314).
Specifically, the frequency change rate stored in the storage unit 201 by the estimation unit 205, the difference between the surface temperature of the magnet 113 and the room temperature of the room in which the measuring device 1 is installed, one small RF coil at a predetermined time The resonance frequency (true resonance frequency) of the installation position of 114 is read out, and the resonance frequency of nuclear magnetization at the installation position of one small RF coil 114 is estimated.
The resonance frequency estimated by the estimation unit 205 is associated with the number of one small RF coil 114 and stored in the storage unit 201.
Thereafter, the resonance frequency estimated by the estimation unit 205 is transmitted to the oscillator 102, and the frequency of the oscillator 102 is set to the estimated resonance frequency value.
A signal having an estimated resonance frequency is oscillated from the oscillator 102 and sent to the modulator 104.
On the other hand, the control unit 169 </ b> B reads the moisture content measurement sequence data from the sequence table 127. Then, the pulse control unit 108 of the control unit 169B controls the operation of the modulator 104, and applies an excitation oscillating magnetic field to the sample 115 from one small RF coil 114 in a predetermined pulse sequence (step 32, 33).
A nuclear magnetic resonance signal corresponding to the excitation oscillating magnetic field is acquired through one small RF coil 114, and the moisture content is calculated by the moisture content calculator 132 (steps 34 and 35).
The moisture amount value is associated with the installation position of one small RF coil 114, stored in a storage unit (not shown) that stores measurement results, and output to the output unit 135.

When the measurement of the moisture content is completed, the mode selection unit 169A refers to a storage unit (not shown) that stores the measurement result, and whether both the moisture content and the self-diffusion coefficient are measured for one small RF coil 114. Judge whether or not. (Step 36).
When it is determined that the self-diffusion coefficient is not measured, the mode selection unit 169A selects a measurement mode for measuring the self-diffusion coefficient from a plurality of modes, and specifies information for specifying the selected measurement mode. The data is sent to the control unit 169B, the data receiving unit 131, and the setting unit 200. The data reception unit 131 sends specific information indicating the measurement mode selected by the mode selection unit 169A to the calculation unit 130.
The setting unit 200 that has received the measurement mode specifying information determines the content of the received specific information. When the setting unit 200 determines that the specific information specifies a measurement mode for measuring the self-diffusion coefficient, the estimation of the resonance frequency in the estimation unit 205 of the setting unit 200 is not performed.
That is, since the estimation unit 205 of the setting unit 200 has already estimated the resonance frequency when measuring the moisture content, the estimation is not performed when measuring the self-diffusion coefficient.
When the fluctuation of the static magnetic field intensity is very large, the estimation unit 205 may estimate the resonance frequency again.
The estimation unit 205 reads the resonance frequency corresponding to one small RF coil 114 estimated at the time of measuring the moisture content from the storage unit 201 and sends the resonance frequency to the oscillator 102. Then, the frequency of the oscillator 102 is set to the estimated resonance frequency value. From the oscillator 102, the resonance frequency signal estimated by the estimation unit 205 when measuring the moisture content is again oscillated and transmitted to the modulator 104.
The control unit 169B reads the sequence data for measuring the self diffusion coefficient from the sequence table 127. The pulse control unit 108 of the control unit 169B controls the operation of the modulator 104, and the gradient magnetic field control unit 171 controls the operation of the current driving power source 159.
The excitation oscillating magnetic field is applied to the sample 115 according to a predetermined pulse sequence, and the excitation oscillating magnetic field and the gradient magnetic field are applied according to a predetermined pulse sequence (steps 32 and 33).
A nuclear magnetic resonance signal corresponding to the excitation oscillating magnetic field is acquired via one small RF coil 114, and the self-diffusion coefficient is calculated by the mobility calculator 133 (steps 34 and 35).
The value of this self-diffusion coefficient is associated with the installation position of one small RF coil 114, stored in a storage unit (not shown) that stores measurement results, and output to the output unit 135.

When the measurement of the self-diffusion coefficient is completed, the mode selection unit 169A refers to a storage unit (not shown) that stores the measurement result, and measures both the moisture content and the self-diffusion coefficient for one small RF coil 114. Determine whether it has been. If it is determined that both the moisture content and the self-diffusion coefficient have been measured for one small RF coil 114, have both the moisture content and the self-diffusion coefficient been measured for the other small RF coil 114? It is determined whether or not (step 37).
When it is determined that there is a small RF coil 114 that has not been measured, the mode selection unit 169A selects a measurement mode for measuring the amount of water by the same method as described above, and the estimation unit 205 The resonance frequency of nuclear magnetization at the installation position of the small RF coil 114 is estimated (step 314), and the moisture content is measured (steps 32 to 37).
Thereafter, the self-diffusion coefficient is measured by the same method as described above.
Such an operation is repeated until the measurement with all the small RF coils 114 is completed.
Then, the moisture amount, the self-diffusion coefficient, and the distribution of the movement amount calculated based on the moisture amount and the self-diffusion coefficient are output to the output unit 135.

Note that the order of measurement of the moisture content and the measurement of the self-diffusion coefficient is not particularly limited, and the measurement of the self-diffusion coefficient may be performed before the measurement of the moisture content.
In addition, when the operator inputs a request to perform only moisture measurement or only self-diffusion coefficient measurement, based on this request, the mode selection unit 169A of the mode switching control unit 169 The first measurement mode for measuring the self-diffusion coefficient or the second measurement mode for measuring the self-diffusion coefficient can be selected.

A current driving power source 159 shown in FIG. 7 is used to supply a current to the G coil 151. The current driving power source 159 does not use a switching power source but uses a transformer or the like.
Further, when the current driving power source 159 is not driven, the transistor is controlled so as not to oscillate minutely due to noise.
Furthermore, it is also possible to employ a structure in which the conducting wire connected to the G coil 151 is cut off when the current driving power source 159 is not driven.
By using the current driving power source 159 having such a configuration, the influence of noise from the current driving power source 159 on the NMR signal can be prevented.

  The apparatus configuration around the sample 115 has been described above. Next, an NMR signal processing block will be described.

As illustrated in FIG. 7, the calculation unit 130 includes a moisture amount calculation unit 132 that is a first calculation unit, a mobility calculation unit 133 that is a second calculation unit, and a movement amount that is a third calculation unit. And a calculation unit 134.
First, the water content calculation unit 132 will be described with reference to FIG.
The water content calculation unit 132 calculates the water content at a specific location of the sample 115 from the intensity of the NMR signal obtained by applying an excitation oscillating magnetic field to the sample 115.
The moisture amount calculation unit 132 includes a data selection unit 132A, a moisture amount calculation unit 132B, and a data selection parameter table 132C.
The data sorting unit 132A sorts NMR signals used for calculating the T ₂ relaxation time constant while referring to the data sorting parameter table 132C.
First, the NMR signal received by the data receiving unit 131 is sorted into an NMR signal having a predetermined intensity or higher and an NMR signal having a predetermined intensity or lower. Then, only an NMR signal having a predetermined intensity or higher is selected, the logarithm of the intensity of the NMR signal is taken, and linear approximation is performed by the least square method. Thereafter, it is determined whether or not the difference between the approximate line and the logarithm of the intensity of the NMR signal equal to or greater than a predetermined intensity is equal to or less than a predetermined value.
An approximate straight line, when the difference between the logarithm of the intensity of a predetermined intensity or more NMR signals is less than the predetermined value, transmits the above NMR signals the predetermined strength to the water quantity calculation unit 132B, T ₂ relaxation time Calculate constants and moisture content.
In addition, since the logarithm of the intensity of the NMR signal decreases exponentially, the logarithm of the intensity of the NMR signal acquired after a lapse of a certain time becomes substantially constant. The data selecting unit 132A, without selecting the NMR signal logarithm becomes constant, logarithm selects only NMR signal before the constant, transmitted to the water content calculation unit 132B, T ₂ relaxation time constant and moisture Calculate the amount.

As shown in FIG. 23, the water content calculation unit 132B includes a relaxation time constant calculating unit 132D for calculating the _{the T 2} relaxation time constant, from _{the T 2} relaxation time constant, and the water content estimation unit 132E for calculating the water content, the correction 132F, a calibration curve table 132G, and a correction parameter storage unit 132H.
When the relaxation time constant calculation unit 132D calculates the T ₂ relaxation time constant, the data is sent to the moisture amount estimation unit 132E. The moisture amount estimation unit 132E accesses the calibration curve table 132G and acquires calibration curve data corresponding to the sample 115. The calibration curve table 132G stores calibration curve data indicating the correlation between the amount of moisture in the sample and the T ₂ relaxation time constant for each type of sample 115.

The water content estimation unit 132E calculates the estimated value of the water content in the sample 115 using the obtained calibration curve data and the T ₂ relaxation time constant calculated as described above.

  The estimated value of the moisture amount calculated by the moisture amount estimation unit 132E is sent to the correction unit 132F. The correction unit 132F corrects the estimated amount of moisture according to the size of the small RF coil 114, and calculates the moisture content.

In the relaxation time constant calculation unit 132D, the T ₂ relaxation time constant is calculated from the NMR signal detected by the small RF coil 114. In this embodiment, the small RF coil 114 that applies the excitation oscillating magnetic field is small. Therefore, the measurement value may be different from the measurement using a large solenoid coil.

  In such a case, the correction unit 132F can correct the moisture content as necessary. The correction parameter storage unit 132H stores a correction parameter and a correction method corresponding to the size of the small RF coil 114, and the correction unit 132F acquires the information from the correction parameter storage unit 132H and performs correction. .

  When the small RF coil 114 is used, basically, a measurement value equivalent to that when an RF coil larger than the sample is used can be obtained. However, when the RF coil is downsized, there is a difference in how the sample is excited. Therefore, in general, factors that cause errors in measurement values such as magnetic field inhomogeneity and SN ratio decrease occur. On the other hand, the influence of the size of the RF coil 114 on the measurement value can be reduced by eliminating the above factors by adopting the arrangement of the small RF coil 114 or the configuration in which the switch unit is provided.

  However, when the small RF coil 114 is minimized, the influence of the RF coil size on the measurement value may appear. As a result of studies by the present inventors on this influence, it has been clarified that an accurate value can be obtained by converting a measured value obtained by the small RF coil 114 using a predetermined constant. Conversion has a mode of multiplying a predetermined constant or adding a predetermined constant, and is selected according to the property of the sample 115 and the like. By obtaining the above constants in advance by a preliminary experiment using a sample to be measured, it is possible to obtain an accurate measurement value that is not affected by the size.

Next, the mobility calculation unit 133 will be described with reference to FIGS.
As described above, the mobility is a physical property value indicating the ease of movement of the protic solvent in the sample, and includes, for example, a self-diffusion coefficient, mobility, and the like. The self-diffusion coefficient is calculated as a property.
Based on the NMR signal obtained by applying the excitation oscillating magnetic field to the sample 115 and the NMR signal obtained by applying a different gradient magnetic field to the sample 115, the mobility calculation unit 133 Calculate the self-diffusion coefficient of water molecules at a specific location.
The mobility calculation unit 133 includes a data selection unit 133A, a self-diffusion coefficient calculation unit 133B, and a parameter table 133C for data selection.
The data sorting unit 133A sorts the NMR signals while referring to the data sorting parameter table 133C. The NMR signal selection method here is the same as the selection method in the data selection unit 132A of the moisture amount calculation unit 132.
As shown in FIG. 25, the self-diffusion coefficient calculation unit 133B includes a self-diffusion coefficient estimation unit 133D that calculates a self-diffusion coefficient, a correction unit 133F, and a correction parameter storage unit 133H.
The self-diffusion coefficient estimation unit 133D calculates an estimated value of the self-diffusion coefficient from the acquired NMR signal using the above-described formula (II).
In the correction unit 133F, the estimated value of the self diffusion coefficient calculated by the self diffusion coefficient estimation unit 133D is corrected according to the size of the small RF coil 114. In the correction parameter storage unit 133H, correction parameters or correction formulas related to correction in the correction unit 133F are stored.

  In the self-diffusion coefficient estimation unit 133D, the estimated value of the self-diffusion coefficient of water is calculated from the NMR signal detected by the small RF coil 114, but the small RF coil 114 that applies the oscillating magnetic field for excitation is small. In the calculation of the self-diffusion coefficient, the measurement value may deviate from the measurement using a large solenoid coil or the like.

  In such a case, the correction unit 133F can correct the value of the self-diffusion coefficient as necessary. The correction parameter storage unit 133H stores a correction parameter and a correction method according to the size of the small RF coil 114, and the correction unit 133F acquires the information from the correction parameter storage unit 133H and performs correction. .

Next, the movement amount calculation unit 134 will be described with reference to FIG. The movement amount calculation unit 134 calculates the movement amount of water molecules based on the water amount calculated by the water amount calculation unit 132 and the self-diffusion coefficient calculated by the mobility calculation unit 133.
The movement amount calculation unit 134 reads the parameter storage unit 134B in which parameters for calculating the movement amount of water molecules are stored, and the calculation formula stored in the parameter storage unit 134B, and calculates the movement amount of water molecules. A moving amount calculating unit 134A.
The parameter storage unit 134B stores a calculation formula for calculating the amount of movement of water molecules from the self-diffusion coefficient and the amount of water for each sample 115 type.
Based on this calculation formula, the movement amount calculation unit 134A can calculate the movement amount.

As described above, the calculated moisture amount, self-diffusion coefficient, and movement amount are presented to the user by the output unit 135.
As shown in FIG. 27, the output unit 135 includes a plurality of small RF coils calculated by the moisture amount calculation unit 132 and calculated by the moisture calculation unit 133 for each measurement region of the plurality of small RF coils 114. The measurement data acquisition unit 135A that acquires the self-diffusion coefficient for each measurement region 114 or the movement amounts for each measurement region of the plurality of small RF coils 114 calculated by the movement amount calculation unit 134, and the acquired measurement values on the same screen Display section 135B for displaying in the partitioned area.
In the display unit 135B, as shown in FIG. 28, the screen is divided into a plurality of regions according to the arrangement position of the small RF coil 114. In each area, a predetermined color is displayed according to the amount of water, the value of the self-diffusion coefficient, and the amount of movement in the measurement area of each small RF coil 114.
In this manner, the measurement position of each small RF coil 114 is displayed by displaying the water content, the value of the self-diffusion coefficient, and the amount of movement of each small RF coil 114 in each region of the display unit 135B. And the amount of moisture etc. can be grasped intuitively.
Thereby, it can be set as the measuring apparatus convenient for a user.

Next, the effect of this embodiment is demonstrated.
Since the measuring apparatus 1 includes the setting unit 200 that sets the frequency of the oscillator 102 based on the resonance frequency of nuclear magnetization at the installation position of each small RF coil 114 when a static magnetic field is applied to the sample 115, Each small RF coil 114 can irradiate an RF pulse having a frequency corresponding to the resonance frequency of nuclear magnetization at the position where each small RF coil 114 is installed.
As a result, a nuclear magnetic resonance signal corresponding to the resonance frequency of the nuclear magnetization at the installation position of each small RF coil 114 can be acquired via each small RF coil 114, and the distribution of moisture content and self-diffusion coefficient can be accurately determined. Can grasp.

Further, the frequency of the oscillator 102 can be manually set based on the resonance frequency of nuclear magnetization at the position of each small RF coil 114 of the sample 115 to which a static magnetic field is applied. On the other hand, if the frequency of the oscillator 102 is manually adjusted and set, it takes time.
In contrast, the present embodiment includes a setting unit 200 that sets the frequency of the oscillator 102 based on the resonance frequency of nuclear magnetization at the installation position of each small RF coil 114 of the sample 115 to which a static magnetic field is applied. Therefore, no effort is required to set the frequency.

When a static magnetic field is applied by the permanent magnet 113, the static magnetic field strength increases or decreases due to the temperature change of the permanent magnet 113 with the passage of time, and the resonance frequency of nuclear magnetization changes.
When the fluctuation of the static magnetic field strength is large, after grasping the resonance frequency of the nuclear magnetization at the installation positions of all the small RF coils, when trying to measure the water content etc., the nuclear magnets at the installation positions of the small RF coils. The resonance frequency of nuclear magnetization at the time of grasping the resonance frequency of crystallization is greatly different from the resonance frequency of nuclear magnetization at the time of measurement. Therefore, accurate measurement cannot be performed.
In addition to this, when the resonance frequency of the nuclear magnetization at the installation position of each small RF coil 114 is grasped, dummy excitation is performed, and then the moisture content and the self-diffusion coefficient are measured as in this embodiment. Therefore, the resonance frequency of nuclear magnetization at the time of grasping the resonance frequency of nuclear magnetization at the installation position of the small RF coil 114 is greatly different from the resonance frequency of nuclear magnetization at the time of measurement.

  On the other hand, the measuring apparatus 1 of the present embodiment changes with time in the resonance frequency of the nuclear magnetization stored in the storage unit 201 and the nuclear magnetization at the position of the small RF coil 114 at a predetermined time calculated by the frequency calculation unit 203. Is provided with an estimation unit 205 that estimates the resonance frequency of the nuclear magnetization at the position of the small RF coil 114 at the time of measurement of the moisture content and the like. Accurately grasp. As a result, the sample 115 can be irradiated with an RF pulse having a frequency corresponding to the resonance frequency of the nuclear magnetization at the installation position of the small RF coil 114 at the measurement time. Can be performed.

Furthermore, in this embodiment, the frequency calculation unit 203 can calculate the resonance frequency of nuclear magnetization at the installation position of each small RF coil 114, and can acquire the resonance frequency of nuclear magnetization at the installation position of each small RF coil 114. . Then, the estimation unit 205 can estimate the resonance frequency of nuclear magnetization at the time of measuring the moisture content and the self-diffusion coefficient.
Therefore, for example, even when a magnet having a non-uniform static magnetic field strength and a large unevenness in the static magnetic field strength is used, the frequency of the oscillator 102 is changed to each of the measurement times of the moisture content and the self-diffusion coefficient. Since it can be tuned to the resonance frequency of the nuclear magnetization at the installation position of the small RF coil 114, it is possible to calculate a highly reliable moisture content and self-diffusion coefficient distribution.

Furthermore, in the present embodiment, in the measurement mode for measuring the moisture content, the moisture content distribution is measured using the small RF coil 114 smaller than the sample 115. Also in the measurement mode for measuring the self-diffusion coefficient, the distribution of the self-diffusion coefficient is measured using the G coil 151 and the small RF coil 114.
In this way, by grasping the moisture content and the self-diffusion coefficient at a specific location of the sample 115, whether the ionic conductivity fluctuation factor in the sample 115 is caused by the moisture content or caused by the self-diffusion coefficient. It is possible to accurately grasp whether it is caused by both the self-diffusion coefficient and the moisture content.
Therefore, the moisture content and self-diffusion coefficient of the sample 115 can be monitored to keep the ion conductivity of the sample 115 always high.
In addition, the moisture amount and the self-diffusion coefficient are measured using the same small RF coil 114, and the moisture amount and the self-diffusion coefficient can be measured at the same position of the sample 115. And the distribution of the amount of movement of water molecules in the sample 115 can be accurately grasped based on the self-diffusion coefficient.

In the present embodiment, since one oscillator 102 for sending RF pulses to a plurality of small RF coils 114 is provided as one, compared to the case where the number of oscillators 102 corresponding to each small RF coil 114 is installed. The size of the measuring device 1 can be reduced.
Furthermore, at the time of measuring the amount of moisture and the like, the resonance frequency of nuclear magnetization at the installation position of one small RF coil 114 is estimated, and after setting the frequency of the oscillator 102, an oscillating magnetic field for excitation is applied to the sample 115, Thereafter, the resonance frequency of nuclear magnetization at the position where the next small RF coil 114 is installed is estimated, the frequency of the oscillator 102 is set, and then the excitation oscillating magnetic field is applied to the sample 115.
Thus, immediately before applying the excitation oscillating magnetic field to the sample 115, the resonance frequency of the nuclear magnetization at the installation position of each small RF coil 114 is estimated and the frequency of the oscillator 102 is set. Even when there is only one, and an oscillating magnetic field for excitation cannot be applied to the sample 115 at a time, an accurate moisture content and self-diffusion coefficient distribution can be obtained.

(Second embodiment)
With reference to FIGS. 29-31, the measuring apparatus 3 of this embodiment is demonstrated.
In the embodiment, the resonance frequency of nuclear magnetization at the installation positions of all the small RF coils 114 is calculated by the frequency calculation unit 203. Thereafter, immediately before the measurement of the moisture content or the like, the nuclear magnetization resonance frequency calculated by the frequency calculation unit 203 and the temporal change of the resonance frequency are taken into account, and the nuclear magnetization at the installation position of each small RF coil 114 at the measurement time. The resonance frequency was estimated.

  On the other hand, in the present embodiment, the frequency calculation unit 203 calculates only the resonance frequency of nuclear magnetization at the position where one small RF coil 114 is installed. Then, immediately before the measurement of the moisture content or the like by the same method as in the above embodiment, the resonance frequency of nuclear magnetization at the installation position of one small RF coil 114 is estimated, and at the installation position of another small RF coil. The resonance frequency of the nuclear magnetization is predicted based on the estimated value of the resonance frequency of the nuclear magnetization at the installation position of the one small RF coil 114 and the resonance frequency distribution.

The setting unit 300 of the measurement apparatus 3 according to the present embodiment includes a storage unit 301 and a calculation unit 302.
The configuration of the measuring device 3 other than the setting unit 300 is the same as that of the measuring device 1 of the above embodiment.

Similar to the storage unit 201 of the above embodiment, the storage unit 301 stores the temporal change calculated by the temporal change calculation unit 204 and the like, and in addition, the static magnetic field strength distribution of the magnet 113 as shown in FIG. Or, a resonance frequency distribution as shown in FIG. FIG. 31A is a diagram showing the arrangement of the small RF coil 114 and the G coil 151 with respect to the sample 115.
The storage unit 301 corresponds to both the first storage unit and the correlation storage unit according to the present invention. That is, the storage unit 301 includes the first storage unit 301B that stores the temporal change calculated by the temporal change calculation unit 204, the static magnetic field strength distribution, the resonance frequency distribution (in other words, one small RF coil 114). The correlation storage unit 301A stores the correlation between the resonance frequency of the nuclear magnetization at the installation position and the resonance frequency of the nuclear magnetization at the installation position of the other small RF coil 114.
As shown in FIG. 30, the calculation unit 302 includes a frequency calculation unit 203, a temporal change calculation unit 204, an estimation unit 205, a prediction unit 303, and a resonance frequency distribution calculation unit 304 that are the same as those in the above embodiment. .
The resonance frequency distribution calculation unit 304 calculates the nuclear magnetization resonance frequency distribution based on the static magnetic field strength distribution of the magnet 113 stored in the storage unit 301, and stores the nuclear magnetization resonance frequency distribution in the correlation storage of the storage unit 301. Stored in the unit 301A.
Here, the magnetic field strength H ₀ [Tesla] has the following relationship with the magnetic resonance frequency ω _f [Hz] of the hydrogen nucleus ¹ H.
ω _f = γH ₀ Formula (C)
Here, γ is the nuclear gyromagnetic ratio, which is 42.6 MHz / Tesla in the case of NMR of the hydrogen nucleus ¹ H. Therefore, if the static magnetic field strength distribution is known, the resonance frequency distribution of nuclear magnetization can be calculated.
The nuclear magnetization resonance frequency distribution is such that when a static magnetic field is applied, the resonance frequency of the nuclear magnetization at the installation position of one small RF coil 114 and the resonance frequency of the nuclear magnetization at the installation position of the other small RF coil 114. (Here, the difference Δω between the resonance frequency of the nuclear magnetization at the installation position of one small RF coil 114 and the resonance frequency of the nuclear magnetization at the installation position of another small RF coil 114).

The prediction unit 303 calculates the resonance frequency distribution of nuclear magnetization stored in the storage unit 301 and the resonance frequency of nuclear magnetization at the installation position of one small RF coil 114 calculated by the frequency calculation unit 203 (frequency calculation in this embodiment). The resonance frequency at the installation position of the other small RF coil 114 is predicted on the basis of the resonance frequency calculated by the unit 203 and further estimated by the estimation unit 205.
The resonance frequency of the nuclear magnetization at the installation position of each small RF coil 114 does not change with the temperature change of the magnet 113, but changes the temperature of the magnet 113 while keeping the mutual frequency difference Δω substantially constant. It fluctuates with.
That is, as the temperature of the magnet 113 changes, only the intercept of the resonance frequency distribution graph shown in FIG.
Therefore, if the resonance frequency of the nuclear magnetization at the installation position of one small RF coil 114 at the time of measuring the moisture content and the self-diffusion coefficient is known, the installation position of the one small RF coil 114 calculated from the resonance frequency distribution of the nuclear magnetization. The resonance frequency of the nuclear magnetization at the installation position of the other small RF coil 114 can be calculated from the difference Δω between the resonance frequency of the nuclear magnetization of the other and the resonance frequency of the nuclear magnetization at the installation position of the other small RF coil 114. .

Below, the measuring method of the moisture content in this embodiment and a self-diffusion coefficient is demonstrated.
First, when the operator inputs a request to select a resonance frequency acquisition mode for acquiring the resonance frequency of nuclear magnetization to the measurement apparatus 3, the operation signal receiving unit 129 receives this request. As in the above embodiment, the frequency calculation unit 203, the frequency change rate calculation unit 207, and the temperature difference calculation unit 208 allow the true resonance frequency, the frequency change rate at different times at the installation position of one small RF coil 114, The difference between the surface temperature of the magnet 113 and the room temperature of the room in which the measuring device 3 is installed is acquired and stored in the first storage unit 301B of the storage unit 301.
Next, when the operator inputs a request to select a dummy mode in which only the excitation oscillating magnetic field is applied without receiving the NMR signal, the operation signal receiving unit 129 receives the request. Perform dummy excitation.
Thereafter, when the operator inputs a request to perform both the moisture content measurement and the self-diffusion coefficient measurement, the estimation unit 205 of the setting unit 300 installs the single small RF coil 114 in the same manner as in the embodiment. Estimate the resonance frequency of nuclear magnetization at. The resonance frequency estimated by the estimation unit 205 is associated with the number of one small RF coil 114 and stored in the storage unit 301.
Next, the resonance frequency estimated by the estimation unit 205 is transmitted to the oscillator 102, and the frequency of the oscillator 102 is set to a value of the estimated resonance frequency. From the oscillator 102, a signal having an estimated resonance frequency value is oscillated and transmitted to the modulator 104. An RF pulse having a predetermined frequency is applied to the sample 115 from one small RF coil 114. Thereby, the amount of moisture at the installation position of one small RF coil 114 is measured.
Next, the self-diffusion coefficient is measured in the same manner as in the above embodiment.
The moisture content and the self-diffusion coefficient are associated with the installation position of one small RF coil 114, stored in a storage unit (not shown) that stores the measurement results, and output to the output unit 135.

When the measurement of the moisture content and the self-diffusion coefficient using one small RF coil 114 is completed, the mode selection unit 169A performs both the moisture content and the self-diffusion coefficient for the other small RF coils 114 as in the above embodiment. Determine whether measurements have been made.
If it is determined that there is a small RF coil 114 that is not performing measurement, the mode selection unit 169A selects a measurement mode for measuring the amount of moisture, and sets specific information for specifying the selected measurement mode in the setting unit 300. send. When the setting unit 300 determines that the specific information specifies the measurement mode for measuring the moisture content, the prediction unit 303 determines the resonance frequency of the nuclear magnetization at the position where the other small RF coil 114 is installed. Make a prediction.
Specifically, based on the resonance frequency distribution stored in the correlation storage unit 201A of the storage unit 301 and the resonance frequency of the nuclear magnetization at the installation position of one small RF coil 114 estimated by the estimation unit 205, other small size The resonance frequency of nuclear magnetization at the installation position of the RF coil 114 is predicted. The resonance frequency predicted by the prediction unit 303 is stored in the storage unit 301 in association with the number of the other small RF coil 114 (installation position of the other small RF coil 114).
Next, the resonance frequency predicted by the prediction unit 303 is sent to the oscillator 102, and the frequency of the oscillator 102 is set to the value of the predicted resonance frequency. As a result, the frequency of the oscillator 102 is
It is tuned to the magnetic resonance frequency at the installation position of the other small RF coil 114 at the time of measuring the moisture content.
A signal having a predicted resonance frequency value is oscillated from the oscillator 102 and sent to the modulator 104. An RF pulse having a predetermined frequency is applied to the sample 115 from the other small RF coil 114. As a result, the moisture content at the installation position of the other small RF coil 114 is measured. The moisture amount is associated with the installation position of the other small RF coil 114 and stored in a storage unit (not shown) that stores the measurement result.
When the measurement of the moisture content is completed, the mode selection unit 169A refers to a storage unit (not shown) that stores the measurement result, and whether both the moisture content and the self-diffusion coefficient are measured for the other small RF coils 114. Judge whether or not. When it is determined that the self-diffusion coefficient is not measured, the mode selection unit 169A selects a measurement mode for measuring the self-diffusion coefficient from among a plurality of modes, and the self-diffusion is performed. Measure the coefficient.
At this time, since the prediction unit 303 of the setting unit 300 has already predicted the resonance frequency at the installation position of the other small RF coil 114, the frequency of the oscillator 102 is set based on the predicted resonance frequency. . Then, the self-diffusion coefficient is measured.
By performing the prediction by the prediction unit 303 as described above in each small RF coil 114, it is possible to acquire the moisture content and the self-diffusion coefficient distribution.
The moisture amount, self-diffusion coefficient, and further, the distribution of movement amount calculated based on the moisture amount and self-diffusion coefficient are output to the output unit 135.

Hereinafter, effects of the second embodiment will be described. In the second embodiment, the same effects as in the first embodiment can be obtained, and the following effects can be obtained.
In the present embodiment, the correlation storage unit 301A of the storage unit 301 stores the nuclear magnetization resonance frequency distribution, that is, the nuclear magnetization resonance frequency at the installation position of one small RF coil 114 and the other small RF coil 114. Since the correlation with the resonance frequency of the nuclear magnetization at the position is stored, the estimation unit 205 estimates the resonance frequency of the nuclear magnetization at the installation position of one small RF coil 114 when measuring the moisture content and the self-diffusion coefficient. Then, the prediction unit 303 can predict the resonance frequency of the nuclear magnetization at the position where the other small RF coil 114 is installed.
Thereby, at the time of moisture content and self-diffusion coefficient measurement, the resonance frequency of nuclear magnetization at the installation position of the other small RF coil 114 can be quickly grasped, and the moisture content and self-diffusion coefficient distribution can be measured quickly. it can.

In the present embodiment, the estimation unit 205 estimates the resonance frequency of nuclear magnetization at the installation position of one small RF coil 114, measures the moisture content, and the self-diffusion coefficient, and then estimates the one small RF coil 114. The resonance frequency of the nuclear magnetization at the installation position of the other small RF coil 114 is predicted on the basis of the resonance frequency of the nuclear magnetization at the installation position.
In one small RF coil 114, the time required for measuring the amount of water is about 1 second, and the time required for measuring the self-diffusion coefficient is about 5 seconds. That is, it can be said that the time for measuring the moisture content and the self-diffusion coefficient by one small RF coil 114 is very short.
Therefore, when the resonance frequency of nuclear magnetization at the installation position of another small RF coil 114 is predicted, the resonance frequency of nuclear magnetization at the installation position of one small RF coil 114 varies greatly from the estimated value. It is hard to think.
Therefore, in this embodiment, it is possible to accurately predict the resonance frequency of nuclear magnetization at the installation position of the other small RF coil 114.

  Further, the static magnetic field strength distribution of the magnet 113 is generally known in advance when the magnet 113 is manufactured. Since the resonance frequency distribution of the nuclear magnetization of the sample 115 can be easily calculated from the static magnetic field strength distribution known in advance, the resonance frequency distribution of the nuclear magnetization of the sample 115 can be easily grasped.

It should be noted that the present invention is not limited to the above-described embodiments, and modifications, improvements, and the like within the scope that can achieve the object of the present invention are included in the present invention.
For example, in each of the above-described embodiments, the solid polymer electrolyte membrane used in the fuel cell is exemplified as the sample 115. However, the present invention is not limited to this, and for example, a fruit, vegetable, or the like may be used as the sample. It is also possible to calculate the sugar content from the self-diffusion coefficient and water content of fruits and vegetables. It is also possible to grasp the growth process of fruits and vegetables based on the self-diffusion coefficient and moisture content of fruits and vegetables.

Furthermore, in each of the above embodiments, the setting units 200 and 300 include the temporal change calculation unit 204 and the estimation unit 205. However, the present invention is not limited thereto, and the temporal change calculation unit 204 and the estimation unit 205 are not provided. Also good.
For example, when using a magnet (for example, a superconducting magnet) whose static magnetic field strength distribution does not change with time, the time change calculation unit 204 and the estimation unit 205 may not be provided. In this case, in the measurement apparatus 1, the frequency calculation unit 203 calculates the resonance frequency of nuclear magnetization at the installation position of each small RF coil 114 and stores it in the storage unit 201 in association with each small RF coil 114. Then, at the time of measurement, the resonance frequency stored in the storage unit 201 of the setting unit 200 may be read to set the frequency of the oscillator 102.
In the measuring apparatus 3, the frequency calculation unit 203 calculates the resonance frequency of nuclear magnetization at the installation position of one small RF coil 114 and stores it in the storage unit 201. Based on the resonance frequency and resonance frequency distribution of nuclear magnetization at the installation position of one small RF coil 114 stored in the storage unit 201 of the setting unit 200 at the time of measurement, the prediction unit 303 installs another small RF coil. The resonance frequency of the nuclear magnetization at the position may be predicted.

In addition, the measuring devices 1 and 3 of each of the above embodiments calculate the water content using the CPMG method and the self-diffusion coefficient of the water molecule using the PGSE method. However, it is not limited to this.
For example, an excitation oscillating magnetic field is applied to a sample by a small RF coil, and a nuclear magnetic resonance signal generated in the sample is acquired. Then, the acquired nuclear magnetic resonance signal may be subjected to Fourier analysis, a spectrum of a chemical shift value indicating the protic solvent may be acquired, and the amount of the protic solvent may be calculated based on the intensity of the spectrum.
For example, when the sample contains water and methanol as protic solvents, the nuclear magnetic resonance signal obtained by the small RF coil is Fourier-analyzed and corresponds to hydrogen nuclei bonded to C atoms. The spectrum is separated into a spectrum corresponding to a hydrogen nucleus bonded to an O atom.
Hydrogen nuclei have different resonance frequencies depending on the nuclide and structure of the chemical bond.
In the case of methanol, the resonance frequency differs between a hydrogen nucleus bonded to a C atom and a hydrogen nucleus bonded to an O atom. The resonance frequency of water hydrogen nuclei and the resonance frequency of hydrogen nuclei bonded to O atoms in methanol are substantially the same.
Since the spectrum having the chemical shift value of the hydrogen nucleus bonded to the C atom can be said to be a spectrum showing only methanol, from the spectrum having the chemical shift value of the hydrogen nucleus bonded to the C atom, the amount of methanol The ratio, the amount of methanol (absolute amount) and the amount of water (absolute amount) can be grasped.

In each of the above embodiments, the plurality of small RF coils 114 are arranged only on the front surface side of the sample 115. However, the present invention is not limited to this. For example, as shown in FIG. A small RF coil 114 may be disposed.
In this case, as shown in FIG. 32, the screen of the display unit is divided according to the arrangement position of the small RF coil 114, and the amount of water, the value of the self-diffusion coefficient, and the amount of movement of each small RF coil 114 are adjusted. In response, a predetermined color may be displayed.

Further, in each of the above embodiments, the measuring devices 1 and 3 have only one oscillator 102, but the present invention is not limited to this, and for example, a plurality of oscillators 102 may be included. Further, the same number of oscillators 102 as the number of small RF coils 114 may be provided.
In this manner, by providing the oscillator 102 in accordance with each small RF coil 114, it is possible to apply the excitation oscillating magnetic field to the sample from each small RF coil 114 almost simultaneously.
Moreover, although the measuring apparatus of each said embodiment performed the measurement using a nuclear magnetic resonance method (NMR), not only this but the thing which performs a measurement using an electron spin resonance method (ESR) Also good.
Further, in each of the above embodiments, the calculation unit 130 of the measuring devices 1 and 3 calculates the spatial distribution of the behavior of the protic solvent at a certain time as the distribution of the behavior of the protic solvent. As the distribution of the behavior of the protic solvent, for example, a distribution indicating a temporal change in the behavior of the protic solvent at the installation position of each small RF coil 114 may be calculated.
That is, the spatial distribution of the behavior of the protic solvent at different times is calculated using the method described in the above embodiments. Then, based on the spatial distribution of the behavior of the protic solvent at different times, a distribution indicating the temporal change in the behavior of the protic solvent at the installation position of each small RF coil is calculated.

Further, in the second embodiment, the storage unit 301 stores the static magnetic field strength distribution of the magnet 113, and the resonance frequency distribution is calculated based on the static magnetic field strength distribution. However, the resonance frequency distribution is stored in the storage unit 301 in advance. May be stored.
In addition, the storage unit 301 of the measurement apparatus 3 of the second embodiment may be connected to the calculation unit 302 of the setting unit 300 via a network.

Moreover, the following methods can also be illustrated as a method of predicting the resonance frequency of nuclear magnetization at the installation position of the small RF coil 114 as in the second embodiment.
(I) A function indicating the resonance frequency distribution (a function indicating the relationship between the resonance frequency and the installation position of the small RF coil, for example, a function for drawing a curve as shown in FIG. 31B) is stored in the storage unit.
The shape of this function is not deformed by the temperature change of the magnet 113, but the height position of the function curve with respect to the resonance frequency axis (that is, the point at which the curve in FIG. 31B intersects the resonance frequency axis (intercept). ) Or the apex of the convex curve in FIG.
The frequency calculation unit calculates the resonance frequency of nuclear magnetization at the position where one small RF coil is installed when measuring the behavior of the protic solvent. Then, by substituting the resonance frequency of the nuclear magnetization of the installation position of one small RF coil calculated by the frequency calculation unit and the installation position of this one small RF coil into the function, The height position of the curve of the function can be determined, and the function can be uniquely determined.
Next, by substituting the installation position of the other small RF coil into the determined function, the resonance frequency of nuclear magnetization at the installation position of the other small RF coil can be calculated.

(Ii) A function indicating the resonance frequency distribution (a function indicating the relationship between the resonance frequency and the installation position of the small RF coil, for example, a function for drawing a curve as shown in FIG. 31B) is stored in the storage unit.
Next, at the time of measuring the behavior of the protic solvent, the frequency calculation unit calculates the resonance frequency of the nuclear magnetization at the installation positions of some of the small RF coils.
A correction unit is provided in the setting unit of the measurement apparatus, and this correction unit determines whether or not the plurality of resonance frequencies calculated by the frequency calculation unit are numerical values corresponding to the functions stored in the storage unit. When the values of the plurality of resonance frequencies calculated by the frequency calculation unit greatly deviate from the function stored in the storage unit, the function stored in the storage unit is corrected.
A prediction unit is provided in the setting unit of the measurement apparatus, and the prediction unit is used to install the remaining small RF coils from the positions of the remaining small RF coils for which the resonance frequency is not calculated and the corrected function. Calculate and predict the resonance frequency of the nuclear magnetization at the position.

(Iii) The frequency calculation unit of the measuring apparatus calculates the resonance frequency of nuclear magnetization at least at the installation position of two or more small RF coils.
A prediction unit that predicts the resonance frequency at the installation position of other small RF coils from the value of the resonance frequency of nuclear magnetization at the installation positions of at least two or more small RF coils calculated by the frequency calculation unit in the setting unit of the measurement apparatus The resonance frequency at the installation position of other small RF coils is predicted.
Specifically, for example, the setting unit interpolates the resonance frequency of the nuclear magnetization between the pair of small RF coils 114 based on the value of the resonance frequency of the nuclear magnetization at the installation position of the pair of small RF coils 114. (Prediction unit).
Then, based on the value of the resonance frequency of nuclear magnetization at the installation position of the pair of small RF coils 114, the interpolating unit interpolates the resonance frequency of nuclear magnetization between the pair of small RF coils.
Thereby, the resonance frequency of the nuclear magnetization in the installation position of the other small RF coil arrange | positioned between a pair of small RF coils can be estimated.

(Reference example)
In each of the above embodiments, it was mentioned that “the strength of the static magnetic field formed by the magnet is not uniform and has a distribution”.
In the second embodiment, “the resonance frequency of the nuclear magnetization at the installation position of each small RF coil 114 does not vary with the temperature change of the magnet 113, but the frequency difference Δω between them is substantially constant. ”And fluctuates as the temperature of the magnet 113 changes”.
Therefore, in this reference example, when the same sample is measured by whether there is a distribution in the static magnetic field strength formed by the magnet and by two small RF coils arranged at different positions inside the magnet, We examined how temperature changes affect the resonant frequency received by two small RF coils.
(Reference Example 1)
First, it was confirmed that there was a distribution in the static magnetic field strength formed by the magnet.
As mentioned in the second embodiment, the static magnetic field strength H ₀ (Tesla) has a relationship shown in the formula (C) with the magnetic resonance frequency ω _f (Hz) of the hydrogen nucleus ¹ H.
If the magnetic resonance frequency ω _f (Hz) is measured, the static magnetic field strength can be calculated from the equation (C).
[Measuring method]
As a sample, pure water was used and sealed in a sample container. A small RF coil (small surface coil) having a diameter of 2 mm was attached to the sample container, and the magnetic resonance frequency was measured based on the nuclear magnetic resonance signal acquired by the small RF coil.
A sample container in which pure water is sealed and a small RF coil are placed in an electromagnetic shielding box. The position of the electromagnetic shielding box inserted inside the magnet was moved at a predetermined interval (2 mm interval), and the magnetic resonance frequency at each position was acquired.
As a magnet, a permanent magnet of 1 Tesla, 45 mm-AirGap was used.

[result]
FIG. 33 shows the resonance frequency distribution measured at intervals of 2 mm. In FIG. 33, the center position of the magnet (the center position of the space inside the magnet) is shown as the origin (zero). FIG. 34 shows a plot of the difference ω (Hz) between the resonance frequency at the center position (zero) of the magnet and the resonance frequency at a position shifted from the center position of the magnet. In FIG. 34, the center position (zero) of the magnet is the reference (0 Hz).
It can be seen from FIGS. 33 and 34 that there is a distribution in the static magnetic field strength formed by the magnet.

(Reference Example 2)
In the reference example 2, when the same sample is measured by two small RF coils arranged at different positions inside the magnet, how the temperature change of the magnet is affected by the resonance frequency received by the two small RF coils. We examined whether it affected.
[Measuring method]
As a sample, pure water was used and sealed in a sample container. Two small RF coils (small surface coils) (diameter 2 mm) were attached to the sample container. The distance between the two small RF coils is 8 mm.
The resonance frequency was measured based on nuclear magnetic resonance signals acquired by two small RF coils. The sample container filled with pure water and the two coils are placed in an electromagnetic shielding box.
The electromagnetic shielding box was inserted inside the magnet, and one small RF coil (Coil A) was placed at the center of the magnet. Accordingly, the other small RF coil (Coil B) is located at a position shifted from the center of the magnet to the end by about 8 mm. One minute after receiving the nuclear magnetic resonance signal with one small RF coil, the other small RF coil was made to receive the nuclear magnetic resonance signal, and the resonance frequency was measured.
The magnet used was the same as in Reference Example 1.
The magnet temperature was 21.6 ° C., the room temperature was 23.5 ° C., and the magnet was in an environment where it could be warmed.

[result]
FIG. 35 shows the temporal change in resonance frequency measured by switching between Coil A and Coil B at 1 minute intervals. FIG. 36 shows the time change of the difference between the resonance frequency measured with Coil A and the resonance frequency measured with Coil B. From these figures, it can be seen that the magnet temperature increases with time, the magnetic field strength decreases, and the resonance frequency decreases. It can also be seen that the difference between the resonance frequency measured with Coil A and the resonance frequency measured with Coil B is kept substantially constant.

(Reference Example 3)
Resonance measured by two small RF coils using Coil A and Coil B of Reference Example 2, with Coil A and Coil B placed so that the center position between Coil A and Coil B coincides with the magnet center The time change of the resonance frequency when the frequencies were almost equal was measured.
Other conditions are the same as in Reference Example 2.

[result]
FIG. 37 shows the change over time of the resonance frequency of the two small RF coils, and FIG. 38 shows the change over time of the difference between the resonance frequencies of the two small RF coils.
From FIG. 37 and FIG. 38, it can be seen that the frequency shifts while the resonance frequency measured by the two small RF coils maintains a constant frequency difference with respect to the temperature fluctuation of the magnet.

  From Reference Examples 2 and 3, the magnetic field strength at two points inside the permanent magnet fluctuates while maintaining a constant relationship with respect to temperature fluctuation, and if the resonance frequency of the sample is measured at one position, the other It can be said that the resonance frequency at the position can be predicted with sufficiently high accuracy.

It is a flowchart which shows the outline | summary of the local moisture content measuring method. It is a figure for demonstrating the compensation function of a CPMG method. It is a diagram for explaining the principle of measuring the the T ₂ relaxation time constant by the spin echo method. It is a figure which shows the example of the pulse sequence of a self-diffusion coefficient measurement. It is a flowchart which shows the outline | summary of the local mobility measuring method. It is a figure which shows the example of a measurement of the self-diffusion coefficient D. It is a block diagram which shows the structure of the measuring apparatus of 1st embodiment of this invention. It is a figure which shows arrangement | positioning of the small RF coil and G coil of a measuring apparatus. It is a block diagram which shows a sensor control part. It is a block diagram which shows a setting part. It is a block diagram which shows the calculating part of a setting part. It is a figure which shows the waveform of the real part of a nuclear magnetic resonance signal and a nuclear magnetic resonance signal, and an imaginary part. It is a figure which shows the table memorize | stored in the memory | storage part of a setting part. It is a block diagram showing a temporal change calculation unit of the setting unit, It is a figure which shows an example of LC circuit. Circuit diagram showing an example of the configuration of the switch section It is a block diagram which shows a mode switching control part. It is a block diagram which shows the structural example of a control part. It is a flowchart of the measuring method concerning a first embodiment. It is a flowchart which shows the process of setting the frequency of an oscillator. It is a figure which shows the table memorize | stored in the memory | storage part of a setting part. It is a block diagram which shows a moisture content calculation part. It is a block diagram which shows a moisture content calculation part. It is a block diagram which shows a mobility calculation part. It is a block diagram which shows a self-diffusion coefficient calculation part. It is a block diagram which shows a movement amount calculation part. It is a block diagram which shows an output part. It is a figure which shows the display states, such as a moisture content of a display part. It is a block diagram which shows the setting part concerning 2nd embodiment. It is a block diagram which shows the calculating part of a setting part. (A) is a figure which shows arrangement | positioning of a small RF coil and a G coil. (B) is a figure which shows resonance frequency distribution. (C) is a figure which shows static magnetic field strength distribution. It is a figure which shows arrangement | positioning and a display part of a small RF coil and G coil. It is a figure which shows the resonant frequency distribution in the reference example 1. FIG. It is the figure which plotted the difference of the resonance frequency in the center position (zero) of a magnet, and the resonance frequency in the position which shifted | deviated from the center position of the magnet. In the reference example 2, it is a figure which shows the time change of the resonance frequency measured by switching Coil A and Coil B. It is a figure which shows the time change of the difference of the resonant frequency measured by Coil A, and the resonant frequency measured by Coil B. It is a figure which shows the time-dependent change of the resonance frequency of Coil A and Coil B in Reference Example 3. It is a figure which shows the time change of the difference of the resonant frequency measured by Coil A, and the resonant frequency measured by Coil B.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Measuring apparatus 3 Measuring apparatus 102 Oscillator 103 Sensor control part 104 Modulator 106 RF amplifier 108 Pulse control part 110 Phase detector 112 Preamplifier 113 Permanent magnet (static magnetic field application part)
114 Small RF coil 115 Sample 116 Sample mounting table 118 A / D converter 127 Sequence table 128 Timing unit 129 Operation signal receiving unit 130 Operation unit 131 Data receiving unit 132 Water content calculating unit 132A Data selecting unit 132B Water content calculating unit 132C Parameters Table 132D Relaxation time constant calculation unit 132E Water content estimation unit 132F Correction unit 132G Calibration curve table 132H Correction parameter storage unit 133 Mobility calculation unit 133A Data selection unit 133B Self diffusion coefficient calculation unit 133C Parameter table 133D Self diffusion coefficient estimation unit 133H Correction parameter storage unit 133F Correction unit 134 Movement amount calculation unit 134A Movement amount calculation unit 134B Parameter storage unit 135 Output unit 135A Measurement data acquisition unit 135B Display unit 151 G coil (gradient magnetic field application unit)
159 Current drive power supply 161 Switch unit 169 Mode switching control unit 169A Mode selection unit 169B Control unit 171 Gradient magnetic field control unit 200 Setting unit 201 Storage unit 202 Calculation unit 203 Frequency calculation unit 204 Time change calculation unit 205 Estimation unit 207 Frequency change rate Calculation unit 208 Temperature difference calculation unit 209 Temporary frequency setting unit 300 Setting unit 301 Storage unit 301A Correlation storage unit 301B First storage unit 302 Calculation unit 303 Prediction unit 304 Resonance frequency distribution calculation unit

Claims (11)

An apparatus for measuring the distribution of the behavior of a protic solvent in a sample using a magnetic resonance method,
A static magnetic field application unit that applies a static magnetic field to the sample;
A plurality of small RF coils smaller than the sample for applying an oscillating magnetic field for excitation to the sample and acquiring a magnetic resonance signal generated at a specific location in the sample;
Based on the magnetic resonance signal acquired by each of the small RF coils, a calculation unit that calculates the distribution of the behavior of the protic solvent,
An output unit for outputting the distribution of the behavior of the protic solvent calculated by the calculation unit;
An RF pulse generator for generating an RF pulse for generating the excitation oscillating magnetic field in each of the small RF coils, and
The RF pulse generator is
An oscillator that oscillates a signal of a predetermined frequency;
A setting unit for setting the frequency of the oscillator;
A modulator that modulates a signal oscillated by the oscillator and generates an RF pulse;
The setting unit tunes the frequency of the oscillator to the magnetic resonance frequency at the installation position of each small RF coil when the static magnetic field is applied to the sample by the static magnetic field application unit, and the oscillator Set the frequency of
The measuring apparatus, wherein the modulator modulates a signal oscillated from the oscillator whose frequency is set by the setting unit, and generates an RF pulse having the frequency set by the setting unit. The measuring device according to claim 1,
The setting unit stores a time-dependent change in magnetic resonance frequency of the installation position of at least one small RF coil in a state where the static magnetic field is applied to the sample;
A frequency calculation unit that calculates a magnetic resonance frequency at the installation position of at least the one small RF coil when the static magnetic field is applied to the sample;
From the change over time of the magnetic resonance frequency stored in the first storage unit and the magnetic resonance frequency at the installation position of at least the one small RF coil at the predetermined time calculated by the frequency calculation unit, the protic solvent An estimator for estimating a magnetic resonance frequency of at least the one small RF coil installation position at the measurement time of the behavior;
A measuring apparatus comprising: The measuring apparatus according to claim 1 or 2,
The setting unit correlates a magnetic resonance frequency at an installation position of one small RF coil with a magnetic resonance frequency at an installation position of another small RF coil when the static magnetic field is applied to the sample. A correlation storage unit for storing;
A frequency calculating unit that calculates a magnetic resonance frequency at an installation position of the one small RF coil when the static magnetic field is applied to the sample;
Based on the magnetic resonance frequency at the installation position of the one small RF coil calculated by the frequency calculation unit and the correlation stored in the correlation storage unit, the magnetic resonance at the installation position of another small RF coil And a prediction unit that predicts a frequency. The measuring device according to claim 3,
The correlation storage unit stores in advance a static magnetic field strength distribution when a static magnetic field is applied to the sample,
Based on the static magnetic field strength distribution stored in the correlation storage unit, a resonance frequency distribution calculation unit that calculates a magnetic resonance frequency distribution of the sample,
The measurement apparatus, wherein the magnetic resonance frequency distribution of the sample calculated by the resonance frequency distribution calculation unit is stored in the correlation storage unit as the correlation. In the measuring apparatus in any one of Claims 1 thru | or 4,
The setting unit includes a frequency calculation unit that calculates a magnetic resonance frequency at an installation position of at least the one small RF coil when the static magnetic field is applied to the sample.
When oscillating a signal of a predetermined frequency from the oscillator and applying an excitation oscillating magnetic field to the sample from the one small RF coil,
The frequency calculation unit obtains a magnetic resonance signal through the one small RF coil,
Calculate the frequency of the imaginary part or real part of the acquired magnetic resonance signal,
An apparatus for calculating a magnetic resonance frequency at an installation position of at least one small RF coil based on an imaginary part or real part frequency and a frequency of the signal oscillated from the oscillator. In the measuring apparatus in any one of Claims 1 thru | or 5,
The measuring apparatus characterized in that the behavior of the protic solvent is at least one of a protic solvent amount, a mobility of the protic solvent, and a movement amount of the protic solvent. In the measuring apparatus in any one of Claims 1 thru | or 6,
The behavior of the protic solvent is at least one of the amount of protic solvent and the mobility of the protic solvent,
A gradient magnetic field application unit for applying a gradient magnetic field to the sample;
Select one of a plurality of measurement modes including a first measurement mode for measuring the amount of the protic solvent in the sample and a second measurement mode for measuring the mobility of the protic solvent in the sample. A mode selection unit to
A control unit that controls the operation of the small RF coil and the gradient magnetic field application unit according to the measurement mode selected by the mode selection unit,
The calculation unit includes a first calculation unit that calculates the amount of protic solvent in the sample based on the magnetic resonance signal acquired in the first measurement mode;
A second calculator that calculates the mobility of the protic solvent in the sample based on the magnetic resonance signal acquired in the second measurement mode,
The controller is
When in the first measurement mode, an excitation oscillating magnetic field is applied to the sample by the small RF coil, and a magnetic resonance signal generated at the specific location corresponding to the excitation oscillating magnetic field is applied to the small sample. Acquired by RF coil,
When in the second measurement mode, an excitation oscillating magnetic field is applied to the sample by the small RF coil and a gradient magnetic field is applied by the gradient magnetic field application unit, and magnetism generated corresponding to these magnetic fields is generated. A measuring apparatus configured to acquire a resonance signal by the small RF coil. A static magnetic field application unit that applies a static magnetic field to the sample, and an excitation oscillating magnetic field to the sample, and obtains a magnetic resonance signal generated at a specific location in the sample, which is smaller than the sample. A plurality of small RF coils, a calculation unit that calculates the behavior of the protic solvent based on the magnetic resonance signal acquired by the small RF coil, an oscillator that oscillates a signal of a predetermined frequency, and the frequency of the oscillator An RF pulse for generating an RF pulse for generating the excitation oscillating magnetic field in each small RF coil, and a modulator for generating an RF pulse by modulating a signal from the oscillator A measurement method that measures the distribution of the behavior of the protic solvent in the sample using a measurement device comprising:
Applying a static magnetic field from the static magnetic field application unit to the sample;
The frequency of the oscillator is tuned to the magnetic resonance frequency at the installation position of each small RF coil of the sample to which the static magnetic field is applied by the setting unit of the RF pulse generation unit, and the frequency of the oscillator is set. And a process of
A signal having the frequency set in the step of setting the frequency of the oscillator is oscillated from the oscillator, and a signal from the oscillator is modulated by the modulator to generate an RF pulse. On the other hand, a step of transmitting an RF pulse having a frequency corresponding to the magnetic resonance frequency at the installation position of each small RF coil;
Applying an oscillating magnetic field for excitation from each of the small RF coils to the sample;
Obtaining a magnetic resonance signal generated at a specific location in the sample via each small RF coil;
And a step of calculating a distribution of the behavior of the protic solvent in the sample by the calculation unit based on the acquired magnetic resonance signal. A static magnetic field application unit that applies a static magnetic field to the sample, and an excitation oscillating magnetic field to the sample, and obtains a magnetic resonance signal generated at a specific location in the sample, which is smaller than the sample. A plurality of small RF coils, a calculation unit that calculates the behavior of the protic solvent based on the magnetic resonance signal acquired by the small RF coil, an oscillator that oscillates a signal of a predetermined frequency, and the frequency of the oscillator An RF pulse for generating an RF pulse for generating the excitation oscillating magnetic field in each small RF coil, and a modulator for generating an RF pulse by modulating a signal from the oscillator A program that controls a measurement device including a generation unit and measures the distribution of the behavior of the protic solvent in the sample,
Applying a static magnetic field from the static magnetic field application unit to the sample;
The frequency of the oscillator is tuned to the magnetic resonance frequency at the installation position of each small RF coil of the sample to which the static magnetic field is applied by the setting unit of the RF pulse generation unit, and the frequency of the oscillator is set. And a process of
A signal having the frequency set in the step of setting the frequency of the oscillator is oscillated from the oscillator, and a signal from the oscillator is modulated by the modulator to generate an RF pulse. On the other hand, a step of transmitting an RF pulse having a frequency corresponding to the magnetic resonance frequency at the installation position of each small RF coil;
Applying an oscillating magnetic field for excitation from each of the small RF coils to the sample;
Obtaining a magnetic resonance signal generated at a specific location in the sample via each small RF coil;
And a step of calculating a distribution of the behavior of the protic solvent in the sample by the arithmetic unit based on the acquired magnetic resonance signal. The program according to claim 9,
The step of setting the frequency of the oscillator includes:
Obtaining a time-dependent change in magnetic resonance frequency at an installation position of at least one small RF coil of the sample to which the static magnetic field is applied;
Calculating a magnetic resonance frequency at an installation position of at least the one small RF coil of the sample to which the static magnetic field is applied at a predetermined time;
From the change over time of the magnetic resonance frequency and the magnetic resonance frequency at the installation position of at least the one small RF coil at a predetermined time, the magnetism at the installation position of at least the one small RF coil at the measurement time of the behavior of the protic solvent. A program for estimating a resonance frequency. The program according to claim 9 or 10,
The setting unit of the measurement device stores a correlation between the magnetic resonance frequency at the installation position of one small RF coil and the magnetic resonance frequency at the installation position of another small RF coil when the static magnetic field is applied. Having a storage unit,
The step of setting the frequency of the oscillator includes:
Calculating a magnetic resonance frequency at an installation position of the one small RF coil of the sample to which a static magnetic field is applied;
Predicting the magnetic resonance frequency at the installation position of the other small RF coil based on the magnetic resonance frequency at the installation position of the one small RF coil and the correlation stored in the storage unit. A program characterized by