CN102607734A - Temperature measuring method and device based on nuclear magnetic resonance principle - Google Patents
Temperature measuring method and device based on nuclear magnetic resonance principle Download PDFInfo
- Publication number
- CN102607734A CN102607734A CN2011104188247A CN201110418824A CN102607734A CN 102607734 A CN102607734 A CN 102607734A CN 2011104188247 A CN2011104188247 A CN 2011104188247A CN 201110418824 A CN201110418824 A CN 201110418824A CN 102607734 A CN102607734 A CN 102607734A
- Authority
- CN
- China
- Prior art keywords
- frequency
- radio
- signal
- magnetic field
- temperature
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Images
Landscapes
- Magnetic Resonance Imaging Apparatus (AREA)
Abstract
The invention discloses a temperature measuring method and a temperature measuring device based on a nuclear magnetic resonance principle. The measuring method comprises the steps of: placing a radio frequency coil internally provided with a signal source in a permanent magnet, emitting power pulses to the radio frequency coil through a pulse generator and a radio frequency power amplifier, radiating radio frequency pulses through the excited signal source, receiving through the radio frequency coil, and processing through a signal amplifying and collecting processing circuit to obtain the signal frequency. The frequency of a magnetic resonance signal is in direct proportion to the magnetic field strength, so that the magnetic field strength can be obtained by measuring the frequency of the magnetic resonance signal. The magnetic field strength of the permanent magnet changes with the temperature, so that a micro temperature change can cause frequency change of the magnetic resonance signal, and the temperature change can be detected by the frequency change. The frequency of the magnetic resonance signal is sensitive to the magnetic field change, so that the method and the device disclosed by the invention can obtain very high temperature resolution. The method and the device are suitable for occasions with high temperature measurement sensitivity demands.
Description
Technical field
The present invention relates to a kind of thermometry and the device that has used this thermometry.
Background technology
Temperature survey is one of field of measurement most important function, and along with the needs of science and technology development and modern industrial technology, thermometry also constantly improves and improves.Traditional thermometry comprises following several kinds at present: the temperature survey of the principle that thermal radiation temperature is measured, resistance temperature is measured, electric thermo-couple temperature is measured, expand with heat and contract with cold etc.There is the not high problem of sensitivity in existing temperature measurement technology, is example with platinum resistance temperature sensor commonly used, and when 273K, every ohm of temperature coefficient of RTD is approximately 0.00392 Ω K
-1Resistance is the platinum-resistance thermometer of 25 Ω under this temperature, and temperature coefficient is approximately 0.1 Ω K
-1, desire to make measured temperature can be accurate to 0.001K, the resistance value that records must be accurate to ± and 10
-4In the Ω.Because the restriction of metering circuit, the sensitivity of measuring temperature is difficult to improve.
Chinese invention patent 200980101841.9 discloses a kind of thermometry, adopts temperature sensitive magnetic material to be placed on measured position, measures variation of temperature through measuring magnetic field.Mainly by magnetic-field measurement sensitivity decision, present magnetic-field measurement method is except magnetic nuclear resonance method in the sensitivity of this method, and other method sensitivity is all lower, and therefore thermometric sensitivity is also lower.Though superconducting quantum interference device (SQUID) sensitivity is higher, only be applicable to measurement, and receive having a strong impact on of environmental magnetic field low-intensity magnetic field, therefore be not suitable for the temperature survey of this method.
Summary of the invention
In order to overcome the shortcoming of prior art, the present invention provides a kind of thermometry and temperature measuring equipment thereof, and the present invention adopts nuclear magnetic resonance principle to carry out temperature survey, can obtain very high temperature survey sensitivity.
The principle of thermometry of the present invention is, a radio-frequency coil that is built-in with signal source is put into a uniform static magnetic field that is produced by the permanent magnet with temperature sensitivity, and described permanent magnet is placed on needs to measure the temperature part.Apply a pulse power to radio-frequency coil, this radio-frequency coil produces a radio-frequency field, the built-in described signal source of described radio-frequency field irradiation, and the atomic nucleus in the signal source is owing to nuclear magnetic resonance is excited.After removing described radio-frequency field; The nuclear radiation that is excited in the described signal source goes out radiofrequency signal; Described radiofrequency signal is received by described radio-frequency coil; Radiofrequency signal is through amplifying and digital filtering, and through Fourier transform, can obtain the frequency of the radiofrequency signal of said signal source institute radiation.Because the radio frequency signal frequency of signal source institute radiation is proportional with the magnetic field intensity of its position, so the frequency of the radiofrequency signal of said signal source institute radiation can be exchanged into its corresponding magnetic field intensity.Because of the temperature correlation of magnetic field intensity and described permanent magnet, its corresponding relation can be demarcated in advance again.The corresponding relation of the magnetic field strength date that measures and temperature of having demarcated and magnetic field intensity is compared; Handle through difference; Can obtain the current temperature of described permanent magnet; Obtain the above-mentioned temperature that needs to measure the temperature part with the current temperature of described permanent magnet, thereby realize temperature survey.
The frequency and the magnetic field dependence of the radiofrequency signal of signal source institute radiation are:
λ＝γB
Wherein: λ is the magnetic resonance signal frequency, and γ is a gyromagnetic ratio, and B is a magnetic induction density.
Based on above-mentioned principle, the present invention provides a kind of thermometry, it is characterized in that; The permanent magnet that will have a temperature sensitivity is placed on the position that needs to measure temperature, and described permanent magnet is in order to producing uniform static magnetic field, and in described permanent magnet, is placed with the radio-frequency coil that comprises signal source; During measurement, apply a pulse power for described radio-frequency coil, make radio-frequency coil produce a radio-frequency field; Signal source in the described radio-frequency field excitation radio frequency coil, signal source radiated radio frequency (RF) signal is gathered described radiofrequency signal; Amplification also converts digital signal into; Convert frequency domain signal to through Fourier transform, the pairing frequency of frequency domain signal peak value is exactly the pairing nmr frequency of said permanent magnet magnetic field intensity, the nmr frequency of having demarcated through comparison and the relation of temperature; Can obtain the temperature of described permanent magnet, also be the above-mentioned temperature that needs to measure the temperature position.
For the 1H atomic nucleus, gyromagnetic ratio γ=42.58MHz/T.
The temperature survey sensitivity of this invention is calculated as follows: for the magnetic field of a 1000Gs, and its corresponding signal frequency λ=4.258MHz.If the temperature variation in magnetic field is 0.5%/C °, then signal frequency is changed to Δ λ=21290Hz.The frequency resolution of receiving circuit is easy to reach 1Hz, so temperature control can reach 4.7 * 10
-5C °.
Because temperature survey process of the present invention is to convert analog level signal to frequency domain signal through Fourier transform, so circuit do not influence measurement result in the error of links such as amplification, so temperature survey has very high degree of accuracy.
Because simulating signal converts frequency domain signal to through Fourier transform, so the signal live width can have certain influence to the accuracy of measuring, and therefore needs the live width of signal narrow as far as possible.The basic method that dwindles live width lets static magnetic field more even exactly, therefore in said permanent magnet, is provided with shimming device.Basic shimming device is to adopt iron plate to be attached on the two poles of the earth of said permanent magnet, changes DISTRIBUTION OF MAGNETIC FIELD with this, makes magnetic field more even.It is to adopt many group coils that another kind makes the magnetic field uniform method, and the electric current of regulating different coils changes the magnetic field that coil produces, thereby the unevenness of compensation static magnetic field reaches the purpose of improving uniformity of magnetic field.
The present invention is to realize with temperature variation through the magnetic field intensity that makes permanent magnet to the measuring method of temperature, and the intensity of the static magnetic field that therefore requires this permanent magnet and produced can change with the variation of ambient temperature.Rare earth permanent-magnetic material generally all has bigger temperature coefficient, reaches 0.3% such as a kind of temperature coefficient of neodymium iron boron NdFeB material, every variation 1 degree of ambient temperature just, and its remanent magnetism Br changes 0.3%.Say that from thermometric angle need the temperature coefficient of magnetic material to be the bigger the better, the temperature control formula of nuclear magnetic resonance temperature sensor is:
η＝1/δγB
η is a temperature control, and δ is the temperature coefficient in magnetic field, and γ is a gyromagnetic ratio, and B is a magnetic induction density.For making η littler, i.e. sensitivity is higher, should make B and δ bigger.For this reason, the present invention adopts the rare earth permanent-magnetic material of high-temperature coefficient, waits like the Nd-Fe-B magnetic pole material of the N35 trade mark and makes permanent magnet, and another benefit of using this material is to become more readily available high magnetic field intensity, and is favourable to improving sensitivity.
Temperature measuring equipment of the present invention adopts following technical scheme:
Temperature measuring equipment of the present invention is mainly by forming with lower component: a permanent magnet; In described permanent magnet air-gap, produce a uniform static magnetic field; In the air-gap of permanent magnet, place a radio-frequency coil, radio-frequency coil is tuned on the pairing magnetic resonance frequency of static magnetic field.Radio-frequency coil is built-in with signal source, and signal source is to contain the nuclear liquid of 1H, such as materials such as water or fat.A pulse producer output RF pulse signal; This RF pulse signal gets into radio-frequency power amplifier through the signal input interface of radio-frequency power amplifier; Drive the pulse of radio-frequency power amplifier output power, radio-frequency power amplifier is connected with radio-frequency coil, this output pulses feed-in radio-frequency coil; Make radio-frequency coil produce a RF magnetic field, be used for 1H atomic nucleus in the excitation signal source; The outside radiated radio frequency (RF) pulse of 1H atomic nucleus in the signal source that is excited; The radio-frequency pulse frequency of institute's radiation is exactly the nuclear magnetic resonance frequency of 1H; This RF pulse signal is received by radio-frequency coil and through signal amplification and acquisition process circuit signal is amplified; Converting digital signal into, is frequency domain signal through Fourier transform, and the pairing frequency of the peak value of frequency domain signal frequency spectrum is exactly the frequency of magnetic resonance signal.Because the frequency of magnetic resonance signal is directly proportional with magnetic field intensity, therefore, the frequency of measuring magnetic resonance signal just can obtain the intensity in magnetic field.And the magnetic field intensity of permanent magnet is temperature variant, and therefore small temperature variation just can cause the variation of magnetic resonance signal frequency.The signal amplification is connected with radio-frequency coil with the acquisition process circuit; Be built-in with the nominal data table of frequency and vs. temperature in signal amplification and the acquisition process circuit in advance; This signal amplifies and the acquisition process circuit compares the frequency data of measured signal and the nominal data table of being stored; And, can obtain the pairing temperature value of this frequency through difference calculating, be measured temperature.Permanent magnet involved in the present invention adopts the higher magnetic material of temperature coefficient to process, such as rare earth permanent-magnetic material or ferrite permanent-magnet materials.Can adopt two utmost point magnets of band yoke on the magnet structure, also can adopt the halbach structure, its objective is in the air-gap of magnet central authorities, to produce uniform static magnetic field.In order to improve the response speed of temperature, reduce the volume of magnet as far as possible, to reduce thermal inertia.The air-gap that reduces magnet can effectively reduce magnet volume, and certainly, method of the present invention is not limited thereto, even big magnet volume also can be used for temperature survey.
Magnet involved in the present invention generally all need carry out the uniform process in magnetic field, therefore need be in the set inside magnetic field of magnet uniform device.This magnetic field uniform device makes that through regulating the position and the size of shimming sheet the magnetic field in the air-gap is more even.In addition, can reach the purpose of regulating magnetic field homogeneity through the electric current that changes coil at the shim coils of the many groups of the arranged around of air-gap.
Through the even process in magnetic field, can the homogeneity in magnetic field be adjusted to the degree that can obtain than narrow linewidth, such as 20ppm or better, then live width is less than 42Hz, if 100 points of sampling, frequency resolution can reach 0.42Hz, can obtain very high temperature resolution.
In the air-gap of magnet, be placed with radio-frequency coil among the present invention, there is a signal source inside of described radio-frequency coil.The effect of radio-frequency coil is to produce RF magnetic field, is used for 1H atomic nucleus in the excitation signal source.Radio-frequency coil is a high frequency oscillator, has high quality factor, and the form of coil can be a solenoid, also can be saddle type, perhaps the quadrature coil of solenoid and saddle type.Coil is operated in the resonance frequency place through tuning match circuit, and is used for producing RF magnetic field and receives the radiofrequency signal that signal source is sent.For obtaining high efficient, signal source should be full of the inner chamber of radio-frequency coil.
The present invention includes pulse-series generator and radio-frequency power amplifier, wherein pulse-series generator produces the radio-frequency pulse of given shape, size and a width, drives radio-frequency power amplifier; Radio-frequency power amplifier is connected with radio-frequency coil, and radio-frequency power is presented to radio-frequency coil.Usually, for obtaining higher magnetic resonance signal, can be with the 1H nuclear excitation of all signal sources; Because there is certain unevenness in magnetic field, needing one has the radio-frequency pulse that necessarily excites bandwidth, such as the pulse of width 1ms; Can excite the width of about 1Hz; For the uniformity of magnetic field below the 20ppm, then can all 1H nuclear excitations be produced enough signal intensities.The pulse shape of pulse-series generator can adopt fixed waveform, also can adopt the waveform able to programme of external control, and its size and width are fixing or controlled too.
Radio-frequency coil of the present invention is the coil form of transceiver, and promptly coil has the function that produces radio-frequency field and receiving magnetic resonance signals concurrently.Radio-frequency power amplifier is connected with radio-frequency coil through a TX/RX switch, and the magnetic resonance signal that radio-frequency coil receives is connected with the acquisition process circuit with the signal amplification through a quatrter-wavelength line, and signal is input to signal amplifier.
The present invention includes a signal and amplify and the acquisition process circuit, the signal of being exported by radio-frequency coil is input in signal amplification and the acquisition process circuit.Signal amplification and acquisition process circuit are mainly by A/D converter, and digital orthogonal demodulator and Fourier transformer constitute, and signal amplification and acquisition process circuit receive the sequential control of pulse producer, and the local oscillation signal of received pulse generator generation.The A/D converter that the signal of radio-frequency coil output enters into signal amplification and acquisition process circuit becomes digital signal; The A/D converter followed is with a digital orthogonal demodulator, and digital signal converts two-way base band orthogonal signal into after getting into digital orthogonal demodulator; The Fourier transformer that entering is attached thereto; Be transformed to frequency domain signal, and calculate the frequency of signal, convert temperature value into.
Description of drawings
Fig. 1 is a nuclear magnetic resonance temperature measuring equipment structural drawing, among the figure: 101 permanent magnets, the even magnetic device in 102 magnetic fields; 103 radio-frequency coils, 104 signal sources, 105 radio-frequency power amplifiers; 106 pulse producers, 107 signals amplify and the acquisition process circuit, the 108TX/RX switch.
Fig. 2 is the magnet structure schematic diagram;
Fig. 3 is a fundamental diagram of the present invention.
Embodiment
Further specify the present invention below in conjunction with accompanying drawing and embodiment.
Shown in Figure 1 is temperature measuring equipment structural drawing of the present invention.Wherein, magnet structure is as shown in Figure 2.Magnet is to be made up of magnetic material and yoke, and perhaps the magnetic material by different DOM rearranges by certain way, in air-gap, forms uniform static magnetic field.On pole plate 201, or magnetic field uniform device 102 is arranged around the circumference of halbach magnet inner chamber.
Radio-frequency coil 103 is installed in the air-gap of magnet, wherein in radio-frequency coil 103, is placed with signal source 104, be full of water or fat etc. in the signal source 104 and comprise the nuclear material of 1H.Radio-frequency coil 103 is connected with radio-frequency power amplifier 105 through a TX/RX switch, amplifies with signal through a quatrter-wavelength line simultaneously to be connected with acquisition process circuit 107.Pulse producer 106 sends the radio-frequency pulse shape with specific time sequence, and control signal is amplified and the work of acquisition process circuit 107.
1H atomic nucleus in the described signal source 104 will be polarized, and the nuclear magnetic moment of 1H will be around the outer magnetic field direction precession, and the nuclear magnetic moment of 1H is exactly a Larmor frequency around the frequency of external magnetic field precession, and Larmor frequency is directly proportional with the size of external magnetic field.Pulse producer 106 produces a radio-frequency pulse, drives radio-frequency power amplifier 105, with the radio-frequency power burst transmissions to radio-frequency coil 103.The radio-frequency field that radio-frequency coil produced is got to the lateral attitude perpendicular to external magnetic field with the nuclear magnetic moment of 1H.After radio-frequency pulse finished, the nuclear magnetic moment of 1H recovered to outer magnetic field direction, and in this process, on radio-frequency coil, induces signal, and the frequency of signal is exactly the corresponding Larmor frequency of external magnetic field.
Described signal is after amplifying; The A/D converter 301 that gets into this signal amplification acquisition process circuit converts digital signal into, passes through digital quadrature demodulation unit 302 again, converts high-frequency signal into baseband signal; The two-way orthogonal signal have been generated simultaneously; The two-way orthogonal signal transform to frequency-region signal through fourier transformation unit 303 with time-domain signal, get final product the frequency values of read output signal.
Fig. 2 is the structure of permanent magnet 101, and Fig. 2 (A) is two utmost point magnets of band iron yoke, and Fig. 2 (B) is two utmost point magnets of Halbach structure.Iron yoke 202 plays magnetic conduction in Fig. 2 (A), and stepless action is carried out in 201 pairs of magnetic fields of pole plate, and in Fig. 2 (B), magnetic field forms uniform magnetic field through the different DOM and the certain arrangement sequence of magnetic material.In two kinds of magnets, what play the responsive to temperature effect is magnetic material, adopts the NdFeB permanent magnetic material; Has bigger temperature coefficient; The perhaps special magnetic material made from high temperature coefficient, general temperature coefficient reaches more than 0.1%, just has very high temperature control; This requirement of the present invention and common permanent magnet are just in time opposite, and conventional permanent magnet needs temperature coefficient low more good more.Certainly, all materials with high temperature coefficient may be used among the present invention.On magnet structure, two utmost point magnets of band iron yoke have stable magnetic field homogeneity, and the live width of signal is controlled easily, but will the weighing of weight ratio halbach structure.The Halbach magnet structure is light and handy, but the stability of uniformity of magnetic field is not as two utmost point magnets of band iron yoke.The magnet of two kinds of structures all can be used for temperature survey.
Fig. 3 is a fundamental diagram of the present invention.Produce a uniform static magnetic field in the permanent magnet air-gap, in the air-gap of permanent magnet, place a radio-frequency coil, radio-frequency coil is tuned on the pairing magnetic resonance frequency of static magnetic field.Radio-frequency coil is built-in with signal source, and signal source is to contain the nuclear liquid of 1H, such as materials such as water or fat.A pulse producer is connected with radio-frequency power amplifier, and output RF pulse signal, this RF pulse signal drive the pulse of radio-frequency power amplifier output power; Radio-frequency power amplifier is connected with radio-frequency coil, and this output pulses is through a TX/RX switch feed-in radio-frequency coil, makes radio-frequency coil produce a RF magnetic field, is used for 1H atomic nucleus in the excitation signal source; The outside radiated radio frequency (RF) pulse of 1H atomic nucleus in the signal source that is excited, the radio-frequency pulse frequency of institute's radiation is exactly the nuclear magnetic resonance frequency of 1H, and this RF pulse signal is received by radio-frequency coil; Through TX/RX switch and one section quatrter-wavelength line; Get into an amplifier, signal converts digital signal through amplifying into through A/D converter; At the process digital quadrature demodulation; Carry out Fourier transform, be transformed to frequency domain signal, the pairing frequency of the peak value of frequency domain signal frequency spectrum is exactly the frequency of magnetic resonance signal.Because the frequency of magnetic resonance signal is directly proportional with magnetic field intensity, therefore, the frequency of measuring magnetic resonance signal just can obtain the intensity in magnetic field.And the magnetic field intensity of permanent magnet is temperature variant, and therefore small temperature variation just can cause the variation of magnetic resonance signal frequency.Be built-in with the nominal data table of frequency and vs. temperature in the signal processing circuit in advance; This signal processing circuit compares the frequency data of measured signal with the nominal data table of being stored; And, can obtain the pairing temperature value of this frequency through difference calculating, be measured temperature.Because temperature survey needs signal processing circuit that high stability is arranged; Therefore adopt digitized quadrature demodulation technology; The frequency resolution of its circuit is higher than 0.1Hz; But the satisfied temperature Testing requirement, because the instability of conventional analogue orthogonal demodulation circuit is not suitable for the application in temperature survey.
Claims (5)
1. thermometry based on nuclear magnetic resonance principle; It is characterized in that; Described thermometry is: permanent magnet (101) placement that will have temperature sensitivity needs to measure the temperature part, and the intensity of the static magnetic field that permanent magnet (101) is produced can change with the variation of ambient temperature; Be placed with the radio-frequency coil (103) that comprises signal source (104) in the described permanent magnet (101); Apply radio-frequency pulse by pulse producer (106) to radio-frequency coil (103); Described radio-frequency coil (103) produces radio-frequency field; The built-in described signal source (104) of described radio-frequency field irradiation; Atomic nucleus in the signal source (104) is owing to nuclear magnetic resonance is excited, and the nuclear radiation that is excited goes out radiofrequency signal, and described radiofrequency signal is received by radio-frequency coil (103); Gather described radiofrequency signal, through amplifying and converting frequency domain signal to, the pairing frequency of this frequency domain signal peak value is the pairing nmr frequency of magnetic field intensity of said permanent magnet; Through the nmr frequency demarcated of comparison and the corresponding relation of temperature, obtain the temperature of said permanent magnet, also be the said temperature that needs measurement temperature position.
2. thermometry according to claim 1 is characterized in that, described radio-frequency coil (103) is tuned on the pairing magnetic resonance frequency of static magnetic field of permanent magnet generation; Signal source (104) is for containing the nuclear liquid of 1H.
3. application rights requires the temperature measuring equipment of 1 described thermometry; It is characterized in that; Described temperature measuring equipment comprises: have permanent magnet (101), radio-frequency coil (103), signal source (104), radio-frequency power amplifier (105), the pulse producer (106) of temperature sensitivity, and signal amplifies and acquisition process circuit (107); Produce uniform static magnetic field in described permanent magnet (101) air-gap; Radio-frequency coil (103) is placed in the inner air-gap of permanent magnet (101); Signal source (104) is placed on radio-frequency coil (103) inside, produces NMR signal; Radio-frequency power amplifier (105) is connected with radio-frequency coil (103), produces radio-frequency power, and radio-frequency power is presented to radio-frequency coil; Pulse-series generator (106) is connected with radio-frequency power amplifier (105), produces radio-frequency pulse, to drive radio-frequency power amplifier (105); Radio-frequency power amplifier is connected with radio-frequency coil, and the magnetic resonance signal input signal that radio-frequency coil receives amplifies and acquisition process circuit (107) is handled.
4. according to the device of the described thermometry of claim 3; It is characterized in that; Described temperature measuring equipment also comprises magnetic field uniform device (102); Magnetic field uniform device (102) is arranged on the pole plate (201) of permanent magnet (101), or in the magnet inner chamber of halbach structure, centers on circumference; This magnetic field uniform device makes that through regulating the position and the size of shimming sheet the magnetic field in the air-gap is more even.
5. according to the device of the described thermometry of claim 3, it is characterized in that, organize shim coil more, reach the purpose of regulating magnetic field homogeneity through the electric current that changes shim coil in the arranged around of described permanent magnet (101) air-gap.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201110418824 CN102607734B (en) | 2011-12-14 | 2011-12-14 | Temperature measuring method and device based on nuclear magnetic resonance principle |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201110418824 CN102607734B (en) | 2011-12-14 | 2011-12-14 | Temperature measuring method and device based on nuclear magnetic resonance principle |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN102607734A true CN102607734A (en) | 2012-07-25 |
| CN102607734B CN102607734B (en) | 2013-06-12 |
Family
ID=46525313
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 201110418824 Active CN102607734B (en) | 2011-12-14 | 2011-12-14 | Temperature measuring method and device based on nuclear magnetic resonance principle |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN102607734B (en) |
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107850651A (en) * | 2015-07-15 | 2018-03-27 | 皇家飞利浦有限公司 | The RF transmitter modules with local field monitoring unit for magnetic resonance examination system |
| CN108139278A (en) * | 2015-10-19 | 2018-06-08 | 罗伯特·博世有限公司 | Magnetic temperature sensor, the method for temperature |
| CN109683116A (en) * | 2018-12-27 | 2019-04-26 | 潍坊新力超导磁电科技有限公司 | A kind of calculation method, device, system and the readable storage medium storing program for executing of special type absorptivity |
| CN111781430A (en) * | 2020-06-19 | 2020-10-16 | 宁波甬东核辐射监测有限公司 | Device and method for simulating X and gamma dose rate measurement in passive mode |
| CN111795991A (en) * | 2020-08-19 | 2020-10-20 | 中国计量科学研究院 | Permanent magnet magnetic moment temperature coefficient measuring device and method |
| CN113075597A (en) * | 2021-03-23 | 2021-07-06 | 东北大学 | Magnet magnetic field measuring method and measuring system |
| CN114754829A (en) * | 2021-01-11 | 2022-07-15 | 中国石油天然气股份有限公司 | Temperature control system and method for magnetic resonance multiphase flowmeter |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20040014236A1 (en) * | 2002-07-22 | 2004-01-22 | Dror Albo | Frequency feedback for NMR magnet temperature control |
| CN101231314A (en) * | 2008-02-21 | 2008-07-30 | 湖南大学 | Method and apparatus for testing magnetosensor resonant frequency elasticity |
| US20090302843A1 (en) * | 2006-06-22 | 2009-12-10 | Commissariat A L'energie Atomique | System for measuring a magnetic resonance signal based on a hybrid superconductive-magnetoresistive sensor |
| CN101692122A (en) * | 2009-10-10 | 2010-04-07 | 苏州纽迈电子科技有限公司 | Temperature control system for nuclear magnetic resonance spectrometer |
| CN102043136A (en) * | 2010-12-08 | 2011-05-04 | 中国科学院宁波材料技术与工程研究所 | Magnetic sensor |
-
2011
- 2011-12-14 CN CN 201110418824 patent/CN102607734B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20040014236A1 (en) * | 2002-07-22 | 2004-01-22 | Dror Albo | Frequency feedback for NMR magnet temperature control |
| US20090302843A1 (en) * | 2006-06-22 | 2009-12-10 | Commissariat A L'energie Atomique | System for measuring a magnetic resonance signal based on a hybrid superconductive-magnetoresistive sensor |
| CN101231314A (en) * | 2008-02-21 | 2008-07-30 | 湖南大学 | Method and apparatus for testing magnetosensor resonant frequency elasticity |
| CN101692122A (en) * | 2009-10-10 | 2010-04-07 | 苏州纽迈电子科技有限公司 | Temperature control system for nuclear magnetic resonance spectrometer |
| CN102043136A (en) * | 2010-12-08 | 2011-05-04 | 中国科学院宁波材料技术与工程研究所 | Magnetic sensor |
Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107850651A (en) * | 2015-07-15 | 2018-03-27 | 皇家飞利浦有限公司 | The RF transmitter modules with local field monitoring unit for magnetic resonance examination system |
| CN108139278A (en) * | 2015-10-19 | 2018-06-08 | 罗伯特·博世有限公司 | Magnetic temperature sensor, the method for temperature |
| CN109683116A (en) * | 2018-12-27 | 2019-04-26 | 潍坊新力超导磁电科技有限公司 | A kind of calculation method, device, system and the readable storage medium storing program for executing of special type absorptivity |
| CN111781430A (en) * | 2020-06-19 | 2020-10-16 | 宁波甬东核辐射监测有限公司 | Device and method for simulating X and gamma dose rate measurement in passive mode |
| CN111781430B (en) * | 2020-06-19 | 2021-05-18 | 宁波甬东核辐射监测有限公司 | Device and method for simulating X and gamma dose rate measurement in passive mode |
| CN111795991A (en) * | 2020-08-19 | 2020-10-20 | 中国计量科学研究院 | Permanent magnet magnetic moment temperature coefficient measuring device and method |
| CN114754829A (en) * | 2021-01-11 | 2022-07-15 | 中国石油天然气股份有限公司 | Temperature control system and method for magnetic resonance multiphase flowmeter |
| CN114754829B (en) * | 2021-01-11 | 2024-05-28 | 中国石油天然气股份有限公司 | Temperature control system and method for magnetic resonance multiphase flowmeter |
| CN113075597A (en) * | 2021-03-23 | 2021-07-06 | 东北大学 | Magnet magnetic field measuring method and measuring system |
| CN113075597B (en) * | 2021-03-23 | 2022-05-06 | 东北大学 | Magnet magnetic field measuring method and measuring system |
Also Published As
| Publication number | Publication date |
|---|---|
| CN102607734B (en) | 2013-06-12 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN102607734B (en) | Temperature measuring method and device based on nuclear magnetic resonance principle | |
| Fiorillo | Measurements of magnetic materials | |
| JP5771692B2 (en) | Low-field NMR apparatus for measuring the water content of solids and slurries | |
| US7449883B2 (en) | Method and apparatus for measuring change in magnetic induction of a magnetic material with respect to temperature | |
| Boero et al. | Fully integrated probe for proton nuclear magnetic resonance magnetometry | |
| Crescini et al. | The QUAX-gpgs experiment to search for monopole-dipole Axion interaction | |
| Yu et al. | A low-cost home-built NMR using Halbach magnet | |
| WO2004106947A3 (en) | Steady state free precession based magnetic resonance | |
| JPH0316554A (en) | Method/apparatus for measuring magnetic field and vortex electric current | |
| Grisi et al. | A single-chip integrated transceiver for high field NMR magnetometry | |
| Li et al. | Reduction of magnetic field fluctuations in powered magnets for NMR using inductive measurements and sampled-data feedback control | |
| EP3465245A1 (en) | Cryogenic field sensing for compensating magnetic field variations in magnetic resonance imaging magnets | |
| Baranowski et al. | High homogeneity B1 30.2 MHz nuclear magnetic resonance probe for off-resonance relaxation times measurements | |
| US20040014236A1 (en) | Frequency feedback for NMR magnet temperature control | |
| Cugat et al. | A compact vibrating‐sample magnetometer with variable permanent magnet flux source | |
| Takeda et al. | Active compensation of rf-pulse transients | |
| Lin et al. | Analysis and design of the transmitting mode on the pre-polarization surface nuclear magnetic resonance system | |
| Wei et al. | Nuclear magnetic resonance measurements in high flat-top pulsed magnetic field up to 40 T at WHMFC | |
| Hassan et al. | High-field emr: Recent cw developments at 25 tesla, and next-millennium challenges | |
| Biller et al. | Characterization of a PXI e based low‐field digital NMR spectrometer | |
| Thurber et al. | Prospects for sub-micron solid state nuclear magnetic resonance imaging with low-temperature dynamic nuclear polarization | |
| Stüsser et al. | Critical exponents, amplitudes, and correction to scaling in nickel measured by neutron depolarization | |
| Gong et al. | JPM-4 proton precession magnetometer and sensitivity estimation | |
| Neronov et al. | Development and study of a pulsed magnetic induction meter based on nuclear magnetic resonance for high magnetic fields | |
| Tseytlin et al. | Decoupling of excitation and receive coils in pulsed magnetic resonance using sinusoidal magnetic field modulation |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant |