JPH06509161A - Magnetic resonance system in real-time industrial application mode - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] Magnetic resonance systems in real-time industrial application mode (technical field) The present invention provides continuous sampling of a process material stream by pulsed nuclear magnetic resonance (NMR) techniques. Concerning instruments for the determination of the type and amount of lattice-constrained and free mechanically active nuclei in In particular, such techniques can be used to analyze moisture, polymer content, crystal content, and other ratios of component analysis. and other parameters for industrial process control applications.

(Background of the invention) Magnetic resonance imaging (MRI) and NMR techniques have been widely used over the past 40 years. Most notably, the field of medical instruments, which typically involves biological testing of various parts of the human body, and It has grown in clinical research applications. Furthermore, industrial instruments and controls of such technology There are uses and interests in application to your work. The present invention and radiant energy-based instruments in the industrial sector to replace or supplement them. Enables efficient (technically and economically) utilization of pulsed NMR techniques.

Pulsed NMR spectroscopy detects the characteristics of the sample being measured. Use a burst or pulse designed to excite all the nuclei of a given nuclide. The protons in such a sample are forced to precess in an essentially static magnetic field. ), in other words the precession is corrected by the pulse. After application of pulse, excitation This results in a free induction decay (FID) of the magnetization associated with the magnetized nucleus. traditional fourier Transform analysis produces a frequency domain spectrum that can be usefully used in studying the core of the problem. to be accomplished. Pulse duration, time between pulses, pulse phase angle and sample set composition is a parameter that affects the sensitivity of this technique. These frequency domain techniques techniques cannot be easily used in industrial applications, especially online applications.

The purpose of the invention is to provide an accurate and rapid determination of the type and amount of the path in question. This is an improved measurement system.

Another object of the invention is the use of time domain analysis in achieving such a system. be.

Another object of the invention is to apply it to the industrial online problem of measurement of control processes. It is to be.

The main variable in question is water, which is the free water content in organic or inorganic materials. Discrimination between bound hydrogens is based on precession analysis of hydrogen nuclei. However, for example, sodium Other parameters can be measured based on the hydrogen or other sensitive species involved.

The purpose of the present invention is to allow such a variety of measurement tasks.

Different densities, temperatures, backing and size factors, frictional and electrostatic Industrial applications including air, vibration, and frequent repeated periodic and aperiodic measurements It is to allow the dynamic characteristics of line applications.

Another object of the invention is to determine the density melt index and/or isostat isostatic index The use of magnetic resonance NMR techniques in polymer analysis, including gas measurements.

Another objective is to enhance the accuracy and reliability of the data obtained.

The aim of the invention is to achieve the necessary practical economy consistent with the above-mentioned aims.

Another object of the present invention is to accurately and quickly determine the type and amount of the nuclide in question. The use of time-domain analysis in systems that applications to in-line problems, e.g. organic or or measurement of free and bound moisture in inorganic materials, or (e.g. sodium of other parameter measurements (based on hydrogen or other sensitive species containing carbon-13 or carbon-13). Integrating all features to determine density, temperature, backing and size factors, friction and Industrial applications including static electricity, vibration and frequent repetitive, periodic and non-periodic measurements The goal is to enable dynamic characteristics for line applications.

Another object of the invention is to refine all the data obtained while achieving the necessary practical economy. Such magnetic co-existence in polymer analysis, including density, increases accuracy and reliability. It consists in using sound technology.

Another object of the invention is that in addition to the two main components (moisture/solid, crystalline/amorphous) Mixtures of NMR active substances (also mixed phase), especially those used in food and plastic materials (and many other Further information regarding industrial online processing (applicable to many NMR-active substances) The aim is to extend the results achieved.

(Summary of the invention) The present invention provides magnetic resonance hardware, control, preferably in the time domain. (and associated data capture and data reduction means and steps) and techniques Provides a substance measurement system using This system can be used on continuous production lines or can be used in conjunction with the acquisition of data from similar repetitive measurement systems. Ru.

Is this NMR system practical in an industrial online context? This results in reliable extraction of free induction damping in a manner that is economically practical. This system The basic magnetic field homogeneity with respect to a reasonable degree of non-uniformity effects and offset , providing temperature stability to a reasonable degree of thermal drift effects and offsets; and the use of statistical methods or other data manipulation for industrially valid measurements. It is characterized by These data are based on the measured samples measured in high static magnetic fields. Transmitted and resonantly coupled radio that induces a modification of the precession of protons in the pull A relatively slow fruit representing the relaxation of protons after initial excitation by a pulse of frequency energy. A first very fast substantially Gaussian time sequence followed by a qualitatively exponential region. discussion/analysis as a free induction decay (FID) curve for the can be provided for.

A Gaussian distribution is present in the sample and is picked up by the receiver of the NMR system. This section is based on measured data points of the magnetization decay of immobile or highly bound protons. Minutes are usually hydrogen or compounds (or similarly, many other N MR active species, such as hydrogen components of sodium-23 or carbon-13) Based on the response of the offspring species (the exponential FID part is usually physically present in the sample loosely bound, such as water that is not substantially chemically combined with it, or Based on unconstrained NMR active species. Gaussian and exponential FID parts and as a whole All FIDs can be extrapolated to the decay origin, which is usually set at the time center of the excitation pulse. Can be done. The zero time intercept of these curves (i.e., FID and one or more of its component curve portion) is the intercept of the FID and/or one or more curve portions. Intersections can be used to provide ratio data, e.g. free water in a water-bearing substance. determine the relationship between minutes and bound moisture (e.g., upstream or downstream corrections, or Industrial chemicals, minerals and (for processing control of metals, agricultural products, and processed foods). Determination of moisture in food e.g. Instead, the objective is to determine the relative crystalline and amorphous components of a substance, e.g. The determination of the ratio of hard and soft components of plastic materials is carried out in a similar way to the measurement can be obtained. Because the FID changes predictably as a function of density, the present invention can also be determined.

In a given measurement such as this, the source of error is that the material has an exponential response such as moisture. This can occur if oils or fats with similar exponential responses or organic solvent components have a similar index response. Ru. Such oils, fats or solvents appear in foods. In some cases, simply water Rather than separating such oil, fat or solvent components from the determination of It is desirable to decide on. Similarly, residual solvents can be as an error factor to be accounted for in the technical data and/or as a target parameter to be measured. appear. The NMR response of such solvent or oil/fat moieties can be measured over several measurement cycles. Using Hahn spin-echo technology as an extension of each It can be isolated by FID initial excitation and Gaussian and finger When originating from the number response part, a new secondary refocusing pulse (usually initial excitation 90" i.e. 180° i.e. pi rotation as opposed to pi/2 pulse) is applied to produce an echo. generated and then a third pulse (also pi) is applied to remove any solvent or oil/fat composition. Obtain a secondary echo, which is a reflection of minutes. This secondary echo is the data stored in the primary FID. and then subtracted from the primary FID to obtain the Gaussian The effective FID intercept can be reduced by analysis of the ratio with the to obtain effective solid/liquid composition (or crystal or moisture) data. Ru.

The present invention also provides a convenient calibration from 3rd order FID to indicate solvent or oil/fat components. including direct extraction of data by Such techniques require the use of such solvents or oils. / Can be extended to some extent to discriminate minute components of fat.

The measurement system of the present invention is economically scalable to widely used research systems. Includes parts that have been downed and hardened for industrial use. A substantially fixed magnetic field A dense space with a magnetic field of 4.000~s, ooo Gauss (nominally 4,700 Gauss) generated by the poles of the distance. Allows for quick adjustment to produce the correct proper magnetic field. It can be adjusted to A barlayed Helmholtz coil is provided. This is the resonant frequency The product of a material-related constant (gamma) multiplied by a certain magnetic field strength matches the excitation frequency guaranteed. Further fine adjustments are made in the signal processing as described below.

The system of the present invention incorporates thermal control to provide a measurement system that meets the above objectives. Large data in a practical manner due to the interrelated characteristics described below. - Allow streams. Materials of construction are also subject to reliability considerations as described below. be integrated. The measurement of samples is often measurements (as opposed to measurements) are performed within a few minutes.

Accurate weight measurement is a necessary feature and is a limitation of many prior art systems. but the intercept ratio and/or integral area under the curve and/or peak value analysis The measurements carried out according to the invention based on It is independent of the product.

in industrial online measurements of the same parameters treated in the main text. Prior art efforts have focused on the same electrostatic/capacitive non-NMR gravimetric, radioactive, acoustic, and optical quantitative systems, but none of them are completely (fulfilling) for this purpose. The use of NMR suitable for continuous industrial processing is an off-line method. constrained by research equipment (of inadequate sampling despite high costs); Early 1980s efforts in pulsed NMR instrumentation were solidified for industrial use. 4% used only one or two data points for FTD analysis. .

For research methods of frequency domain NMR analysis, see, for example, Chongyang, by 5 Piess. Molecular dynamics of solid polymers as revealed by molecular NMR (Mo1e c’ular Dynamics of 5solid Polymers A s Revealed By Deuteron NMR) J (261Co1 1oid & Polymer 5science, 193-209.1983 ), and Kau fman et al. Determination of transient temperature and crystalline components of high molecular weight polyethylene (Determina) tion of Transition Temperatures and C rystalline Content of Linear Htgh Mo decujar-Weight Po1yethyl’ene by Prot on NMR5pectroscopy) J (27Jl, of Polyme r　5science　2203-2209.1989), the crystalline component The decision is described. Pulsing in coal for detection of free radicals and Time-domain analysis using multipulse NMR/free induction decay shows that protons in coal Utility of Pulsed Nuclear Magnetic Resonance in Research Nuclear Magnetic Re5onance In Studyi ng Protons in Coals) J (81Jl, of Phys, Chem.

556-571.1977) and “IH nuclear magnetism of domain structures in polymers. Research on Ki Resonance (IHNuclear Magnetic Re5onanceS) tudies of Domain 5 structures In Potym ers) J (52(9) J, Appl, Phys, 5517-5528.1 (981) reported in Gerstefn et al. iversity Ames Laboratory) research system. ing. IBM Federal Systems Division model and Brucker GmbH model P2O1 equipment or previous equipment, and Pearson U.S. Pat. No. 4.430.719, issued February 7, 1984. The above-mentioned early attempt at industrial application of NMR methods is described in the above-mentioned issue. Pea rson research is carried out by Kaiser Aluminum & Chemica1. It was realized in 1985 in industrial plant control research. This is reliable It was not effective as a quantitative device. Auburn International' ona 1 company used Pearson/Kais for sales in 1987-1988. er products and failed to meet the demand for industrial online monitoring.

Other objects, features and advantages may be found in the preferred embodiments hereinafter with reference to the accompanying drawings. It will become clear if you read his detailed description.

(Brief explanation of the drawing) 1 and 2 are electrical block diagram configurations illustrating modifications of the examiner elements in FIG. IA. Side and cross-sectional views of the preferred embodiment of the invention, including the elements, FIG. The free induction decay (FID) of the example of FIGS. 1 and 2 in voltage versus time in shows the waveform at FIG. 4 shows the structure of FIGS. 1 and 2 including the signal processing elements (the operation of which is shown in the waveforms of FIG. 3). Flowchart of measurement steps using the device, Figure 5 shows the burn spin echo The free induction damping (FID) of the embodiments of FIGS. 1 and 2 modified for use The waveforms in voltage versus time for the signal processing elements (the operation of which is shown in the waveforms in Figure 5) are shown in Figure 6. Figures 1 and 2 modified for burn spin echo utilization, including Flowchart of the measurement steps using an example and showing the determination of density and moisture FIG. 7 shows a modification of the invention that allows relative and absolute density measurements of samples. voltage (or other Various strength parameters) vs. time, Figure 8 used for polyethylene Calibration curves for absolute density measurements using said embodiments of the invention, and 9A, 9B, and 90 show how to establish the change in the decay time constant and apply the preset factors to the schedule. simple peak readings (average) instead of full FID analysis (reuse) further characteristics to determine other components such as solvent or oil/fat in the sample. Fig. 3 is a decay curve for density (I) versus time (1) illustrating the operation of the modified example according to Fig. 1;

(Detailed description of preferred embodiments) 1 and 2 are cross-sectional views with intervening block diagrams of a first embodiment of the invention. Has a flow. A portion of the material is captured by the probe P and passed through the intake line LI. and sent to sample area S1. The region typically has substantially interfering F Substantially non-magnetic, non-conducting materials (glass, certain ceramics) that do not produce an ID signal approximately 0.30 m (1 ft) made of It is defined by a length of tube 98. This sample area consists of the inlet valve v1 and the outlet It is defined between valves 72. A gas flow J is also provided. These are the sample inflows. and is repeatedly switched on and off to agitate the flowing sample during discharge.

Region S2 is the critical part of the sample. This region is resonantly wound and line circuit 102 and associated transmitter/receiver controller 104. The sample coil 100 is surrounded by a sample coil 100 that is driven by the sample coil 100 . The ground loop 101 is Active rails are provided above and below the coil 100 to help shape the magnetic field of the coil 100. is a Kent's law shield, i.e. includes a magnetic field established by the excitation pulse. control controller 104 includes an on-board microprocessor, necessary power elements, memory, program and the illustrated hardware, and the keyboard 108, monitor (or other display) 110, recorder 112 and/or processor. An external microcontroller 114 (controls processing in IPL) It includes an I10 decoder suitable for connection to computer 106. The operator is Initiating and controlling operations from the display keyboard 108 and displaying the resulting data and The signal is then shown on the display 100 and 110, 112 and/or 114. Computer 106 also controls the operating conditions of the equipment. do.

Region S2 of tube 98 and coil 100 is static but magnetic assembly 116 The assembly is in an adjustable crossed magnetic field defined by the yoke 118, the pole 120, a surrounding Helmholtz coil 124, and a coil current generator 122. include. The critical sample area S2 of tube 98 and the magnet interact to generate harmonics and from coil 100 to the sample and/or from the sample to coil 100 and coil 100. and returned to be picked up by the winding circuit 102 and the transmit/receive controller 104. Metallic (but non-magnetic) box 12 to minimize other interference with the microwave signal Included in 6.

Magnetic assembly including yoke 118 and other internal components as shown in FIGS. 1-2 116 further includes a gas fill and purge control (not shown), an internal gas heater 1 34, the fan 136 driven by the motor M, and the yoke and its temperature are extremely high. 120 and other detection zones that reflect the temperature in the sample zone therebetween. contained within an environmental control room 132 having a temperature sensor 138 capable of heat control Roller 140 processes the temperature signal from 138 to 134/136 as a coarse control. and a Helmholtz coil at the pole piece 120. 124 as a sensitive and quick fine control while the computer implements general control instructions for the controller 106. Additionally, pump 144 and yoke 118 and a coil 148 attached to plate 128 of box 126. Thermal stabilization is provided by a closed loop heat exchanger 142. yet another or Alternatively, thermal stabilization may be achieved using a closed-loop heat exchanger or heated air as shown in Figure IA. obtained by an airflow tube, which contains the same tube containing the hot air flow supplied over the length of the tube. It is defined between concentric cylinders W1 and W2 that extend the entire length of the tube SIA.

The strength, uniformity and constancy of the magnetic field between the poles 120 in the region S2 of the sample are determined by this It is controlled by a uniform basic magnetic field in the entire region S2, as shown in FIG. helmhol The second coil 124 is energized by a coil current controller 140 to Accurately adjust the final strength of the applied magnetic field. This magnetic field is generated by the magnetic pole piece 120 and It is the vector sum of the magnetic field due to the Helmholtz coil 124. Controller 14 0 sets the current flowing through the Helmholtz coil 124 using a current generator. . The coil 124 is configured so that the magnetic field generated by the current in the coil 114 is generated by the magnetic pole piece 120. wrapped around the magnet 110 so that it can be added to or subtracted from the resulting magnetic field. . The magnitude of the current flowing through the coil 124 is determined by the magnitude of the current flowing through the pole piece 120 (and the associated yaw Helm determines the strength of the magnetic field that is added to or subtracted from the magnetic field due only to the The actual determination of the current flowing through the Holtz coil is as follows: until the maximum sensitive resonance is obtained. Perform the magnetic energy and resonance techniques described below in the preliminary run.

This is achieved by adjusting the Helmholtz current.

The main elements of the electrical control section are coils 100, 101, and variable capacitor 10. 2-1.102-2, resistor 102-3, diode 102-4, 20 to A tuning circuit 10 configured to achieve resonance of the coil 100 by tuning to a Q of 50. 2, and transmit/receive switch 1o4-i, transmitter 104-2 and receiver crystal oscillator 104-4, gate pulse generator (PPG) 104 -5, and the control unit 104 including the phase shifter 104-6. This crystal is By the MOD and DEMOD elements of the transmitter 104-2 and receiver 104-3 Provides a nominal 20 MH2 carrier wave that is phase modulated or demodulated. receiver includes variable gain amplification elements 104-31, 104-32 for operation. received The output analog signal is sent to the high-speed flash converter 105-1 and ) is sent to the internal CPU element 105-2, and this CPU is sent to the keyboard 10 8, monitor 109, modem 110, recording element 112, and e.g. Valve control 115 and (or or) a processing controller for controlling the valves V1 and v2 via the coil current control section 122. It has a troller element 114.

Excitation of the coil 100 and excitation of the proton content of the sample and subsequent relaxation/decay-years The differential motion produces a received FM signal with controlled gain amplification after demodulation, A/D conversion and The plot of points has the shape C of the free induction decay (FID) curve shown in Figure 3. Ru.

The voltage vs. time relationship in Figure 3 corresponds to the “cycle” (+ and – subcycles) of sample excitation. (cycle) and the free induction damping. (+) / (-) each subcycle In the pulse, a pulse of excitation energy is applied. The center of this excitation pulse is to It will be done.

The electronic components of transceiver 104 continue to operate until saturation effects are overcome at tl. Not validly received. A usable curve C(+) or (C-) then results. Faith The signal processor generates continuous C+ and C- waveforms for effective adjustment as described below. can be added or subtracted.

The FID curve data is stored in an external computer 106 where the program Find the best curve that fits each stored FID curve. The FID curve is shown in Figure 3. It has two components, designated as A and B. The first part of the FID curve The A curve that governs is a Gaussian curve, and the 8 curves that govern the subsequent part of the FID curve The line is an exponential decay. The Gaussian and exponential parts represent the sample constraints and and the unbound proton component (e.g., (1) the sample mass of water or A mixture of polymeric molecules and other water components (moisture), (2) polymeric substances and lightly polymeric substances. co-occurring crystalline and amorphous components, and (3) a mixed elastomeric polymer. component). Once the curve is known, it is located at the theoretical center of the transmitted burst signal. The delay is extended back to the origin of time (denoted as tO-1, i.e. the excitation of cycle 1). Since the FID curve C can be long, it is important to determine the type of curve that makes up the FID curve C. this This means that the saturation effect of the electronic device that occurs from the end of the burst signal to tl is It is important because it exists. During this time, measurements cannot be made accurately, but The problematic area under the curve, which is the measured value of the box, extends from to to t4, and beyond this Then the curve is too small to matter and the electronic element is (starting with a pulse) requires recovery time.

Each (sub)cycle reaches t5 for recovery, i.e. a new transmitted signal burst 1-(t A substantially complete relaxation state of the protons of the sample before the onset of O~2) is possible. typical , the excitation pulse interval is 5-10 ms, and the tO-t1 time is 5-15 ms. milliseconds (the shorter the better), and the effect of the bound nucleus (Gaussian effect) is dominant. t1-t2 is a duration of 5 to 15 milliseconds (critical measurements are taken over a narrower area tm ), t2-t3 is an indistinct transition of 15-25 ms duration. t3 to t4 is a region in which the unbound (exponential) component is predominant, and the The duration of the decay portion is 300 to 500 milliJ seconds. nearest index curve fits the C curve in the t3-t4g region, where the C and 8 curves are substantially is equal, this 8 curve is extrapolated again to tQ, i.e. 8 curve and at to Establish its virtual B' component and BO intercept. This exponential curve is A (Gaussian) It is subtracted from the C curve in the region where the curve is dominant (t2-t3). results and The curve obtained by doing this fits the best least-squares Gaussian curve. This best Gaussian curve is then extrapolated again to to to include the virtual A′ component and AO intercept at to. Establish the A curve.

The resulting data used in computer 106 (FIGS. 1-2) is , to and 8 curves, and their intercepts at tQ and their BO/AO +BO ratio. Each of these curves (and their intercept) has the same We define the A (Gaussian) curve, which is exponentially and theoretically related to the nucleus, but surrounded by a lattice structure. Contains groups of nuclei that arise. The nucleus that gives rise to the B (exponential) curve is either unbound or is not comparatively bound.

The data may be used in line IPL (Figure 1) or associated equipment (e.g. during drying or calcination, continuous chemical or metallurgical reaction processes, etc.)Q Can be used as C type measurement or online control parameter.

The input operating parameters of the system are in the form of FROM or pre-stored in ROM. parameters stored or input sent to the telephone line and modem 110. It can be widened to include The RF signal is generated using a coil or antenna equipment. This can be achieved by a number of techniques including positioning. Stable magnetic fields can be created by electromagnets, permanent magnets, super Can be produced by electromagnets with conductive windings or other magnetic techniques that produce magnetic fields. I can do it.

Figure 4 is an expanded flowchart showing the measurement steps to establish valid industrial measurements. be. First, the sample area is clear in the shortened cycle of trying to establish curve C. A free induction decay curve C is established to investigate whether (rapid FTD) If the area is not clear (N), the measurement is blocked and valve v2 is (re)opened, and Allow flow J and gravity to clarify the area. Next, close valve v2 and open valve V1. This arrangement of probe P and line Ll as necessary to ensure sample acquisition. The sample is introduced by making appropriate adjustments. Flow J prepares and stabilizes new samples. to be established.

The temperature control sections 134-138 and 142-146 described above are very coarse and Establish relatively coarse thermal control to counter sample temperature changes.

The baseline for the electronic signal processor is 30-40 cycles ((C+) and (+) and (-) subs that add (C-) to detect the offset and compensate for it. cycle). further by coil 24 to adjust HO. Adjustment is established and this takes 10 to 20 magnetic field test cycles of FID curve generation. It becomes more possible. (C-)F[) is subtracted from (C+)FID, i.e., absolute The C values are summed to obtain the effective FID derivative with the maximum at resonance. this HO continues to flow through coil current generator 122 and coil 124 until a maximum value such as adjusted via. These measurements are reliable areas for such purposes. (The above baseline measurements are also done here). Adequate magnetic field adjustment typically occurs in 7 cycles or less.

50 to 500 cycles are then performed to obtain usable measurements. These 50 Each of the ~500 cycles includes transmit/receive/flash analog/digital conversion and and data storage. Then curve fitting, 10 intercepts and BO/AO+ Curve averaging is performed to establish the BO ratio. similar but slightly truncated The cycle can be used for rapid FID, magnetic field testing and baseline correction. can. Each subcycle [(+) and (-)] of each cycle consists of thousands of FIDs. Including point acquisition and use of hundreds of such points in data reduction.

If many cycles are used for one measurement, the (digital) curve C The amplitudes of the points are stored and a least squares fit to such data points is established. Ru. Furthermore, in order to eliminate the zero error mentioned above, the plus and one values are alternated. be taken in.

The area under the squared derivative of the FID curve is integrated (rint, J), and the area under the squared derivative of the FID curve is The area under the differential is integrated to establish a ratio, the square root of which is L/(KS plus). , where L is the liquid (moisture) value obtained from the index value, K is the constant, and S is the Gaussian value. The quantity associated with the solid (or bound proton), (KS+L), is due to resonance. All protons that are (and can be) affected.

It also provides greater accuracy and reliability than examiner components can corrupt readings. It was discovered that. glass is not used (and glass is avoided in industrial applications) (preferably), then the substitution should not be a hydrocarbon plus deck.

However, (with conditions tuned to the resonance for hydrogen that is 1-+ for moisture measurement), fluorine These signals work in resonance cases and at the sensitivity level required for such readings. Because it can be distinguished from the reading related to the moisture content, and if necessary, it can be separated ( Fluorocarbons may be effective in some applications because they can be . e.g. weighing the mutual proportions of these species in amorphous and crystalline mixtures In other cases of higher measurements, the sample container may be glass or non-proton ceramic. Must be a lock. In all such cases, the main focus is on the transmitted energy. Avoid sample containers with species that can combine with FID decay curves to misread sample readings. Is Rukoto. The present invention addresses the hitherto unrecognized discovery of such cases. Contains the system response to

FIG. 5 shows another NMR decay using again the same component terminology of the NMR decay waveform of FIG. The MR attenuation waveform is shown. Examples of modifications to the operation of the method and apparatus of FIGS. 1 and 2 (and In examples of changes in structure and control settings that result in such altered behavior, mO Each waveform is triggered by another pulse centered at ' and mo' to burn. Gives rise to a spin-echo response. The falling part of the echo (in the following text, D and (referred to as D and E) are mainly non-greasy solids and non-oily solids, and the original F except based on the response of the sample with no response of the insoluble liquid component. It has the same general pattern as ID C, but FID C has solid, water and oil/ This is a measurement of the significant response to pulsed excitation by all of the fat or solvent components.

Time t1', t2', t3', t4' and t1', t2'', t3', t4'' are the rough analogs of time points t1, t2, t3, and t4 of FID C mentioned above, respectively. Defined for D and E as values. However, C (resulting from 900 revolutions) There is a markedly different effect on the echo (resulting from a 180' rotation) compared to . FIDC has a duration on the order of about 1 millisecond, with each echo typically , about 2 mm as controlled by the selective timing of P', P' in relation to P. have durations on the order of seconds, but these intervals are sampled more or less Virtually configure for different materials and different sets of instrument electronics specifications be able to. Almost all C times are attenuated compared to the second half of each echo. combined in a process. The effective beginning of the decay for D and E is tO' and tQ'' at the actual peak, but tO for C is the excitation pulse set in the middle of the Reduced eating C/D/E is +c/ in Figure 3 mentioned above. (For the same purpose as knee j!-P cycle-C/D,/E Nakab cycle They take turns at FID's C(/''Pulse to start C- °(pj/2) rotation, but the pulse P+ for +D, -D, +E, -E , P', P'4-1P'- each produce a rotation of]80° (p i).

A block diagram of the operation of FIG. The same human factors mentioned in +, P- excitation) including multiple cycles of baseline correction and magnetic field testing; The adjustment and measurement of is substantially the same as that of the burn spin eco By using -.

The signal processing for this measurement consists of Gaussian and exponential sub-fields obtained from the adjusted FTD C. C and E decays by using the zero time intercept and/or integral of the following curves Storing the digitized data points of, subtracting E from C, and FIGS. 3 and 4 The process includes the adjusted FID C processing substantially as described above. If there is The E decay peak is used to quantify solvent or oil/fat components.

Furthermore, the FID C data before or after adjustment by subtraction of E is can be used as a determinant of density on a relative basis. Figure 7 shows maximum, medium and was set for the lowest density polyethylene sample 7-1.7-2.7-3. Indicates FID. This curve shows that the difference is 1: detectable by the signal processing device mentioned above. be different enough so that

The appropriate tO'' setting for the E-peak value itself will be applied on subsequent measurement days (or weeks, or months). Pre-configured for instruments such as those used for certain substances that are analyzed on-line is determined as a configurable calibration factor. Figures 9A, 9B, and 9C show that this is done Under non-resonant coupling conditions (carefully induced in coil 100 of FIGS. 1 and 2) generated by running the curve CSD,E in Fig. 5 using the crudely calculated tO' of The C and E curves are shown as if they were made and superimposed. The difference in the intercept of the X axis (C and Δt) determined by shifting the curve until the zero intersections of E coincide, Later execution during resonance of FID decay due to burn spin echo using LO' of provide a correction factor to yield an adjustment LQ'' with respect to tQ used in tQ, i.e. , in such a later run, the digitizer/flash converter (Figure 1.1 05-1) is gated to open at time tOa'' after time to. The last peak values of C and E at are also analyzed and in any superposition The attenuation of tl compared to what would occur if tQ' actually matched to without A correction factor f is obtained as the ratio C/E to be used in the subsequent reading of E to compensate. this is a reasonable correction since C in LP is entirely due to solvent or oil/fat effects. Therefore, the measured E is smaller than the measured C at LP simply due to attenuation.

Furthermore, the intensity I parameter (e.g., voltage) is over a range that includes the nominal position of are measured and averaged to produce an average value that can be used with greater confidence.

Finally, per duram in each phase of interest (e.g. solids, water, oil/fat) Due consideration must be given to the relative abundance of protons (or other NMR active species) in the Must be. These phases or components or other percentage data, e.g. Appropriate calibration constants can be generated to determine the concentration of crystallinity.

For example, the oil/fat ratio P is determined by the following formula. That is, P = KeEo/ (KeEo+KaAo+KbBo) However, are KeSKa and Kb standard substances? The calibration factor obtained from AOlBOlEO is the to-intercept after using the above correction factor. Ru. The density (d) of the sample material as a whole is shown in Figures 7-1, 7-2, and 7-3. or by the curve analysis described earlier, or for plastics (and other materials). can be determined by the following formula.

That is, d = M [KaAo] / [KaAo+KbBo+KeEo] +N However , the fraction in parentheses is the crystallinity ratio, and M and N are the experimentally obtained calibration factors. child (usually a constant for the substance used consistently after the initial decision).

The density of a component is usually an additional term in the formula, but in the case of plastics , the crystalline and amorphous components have closely related fundamental densities, (M, incorporated into the N factor The density term can be omitted (unless otherwise specified).

For other substances, the formula is d = (M) [KAodal/[KAoda+KBodb+KEodel] +N where da, db and de are the density of the component.

For some materials, a more complex and essentially more accurate nonlinear function can be calculated from the data points. density plots and/or ratios [or other parameters] laboratory determination of the same parameters for the same sample). or automatically (i.e., by a computer program), superimposing this Statistical methods can be used to obtain a second- or third-order fitted calibration function. can. Subsequent decisions according to the invention can be adjusted by such a calibration function. It is possible.

Figure 8 shows such a polyethylene density measurement according to the invention (Y-axis) and the standard Calibration curves for density measurements (Y-axis) of the method (e.g. oil bath float) are shown and Demonstrates effectiveness. Other standard methods include acoustic transmission methods.

Those skilled in the art will appreciate that the invention is limited only by the scope of the claims, construed in accordance with patent law, and that equivalent Other embodiments, improvements, details and applications within the scope of the invention, including teachings of the art, may be found in the text. It will be clear that this is possible according to the letter of the disclosure.

Engraving (no changes to the content) Engraving (no change in content 1) FIG. 5 electronic r14 adjustment Engraving (no changes to the content) time Regression rate: 0.94873 Correlation rate: 0.99 General adjustment relationship diagram June +8j990 8.24 Procedural amendment (Ryatsu Ella. workman . Tsuki Oto Stomach Go

Claims (1)

[Claims] 1. In a magnetic resonance system for industrial process monitoring, (a) an industrial process access successive samples from the area, place these samples in the sample measurement area, and (b) applying a fundamental magnetic field to said region to discard the internal sample; Produces a precession of the nucleus of the material and corrects the precession by applying a local resonant excitation pulse to the region (c) means for measuring nuclear precession and core interaction with said sample; the receiving antenna, which produces a relaxation that is detected as free induction damping in the means defining a coil means and a signal transmission means; (c) Establish a digitized version of the free induction damping and constrain it to the damping curve. The above of one intercept of said component is analyzed into a (Gaussian) component and an unbound (exponential) component. means for extracting the ratio of the component to the sum of intercepts, the means (a) to (c) comprising: (1) in response to changes in one or more parameters of sample conditions in said measurement region; , the use of the basic magnetic field and the stabilization of the excitation and transfer conditions; (2) the removal from the process; Rapid and repetitive measurements of ratio and related stability on successive samples and perform the extraction, (3) Interpret at least 1000 data points in each decay curve and In both cases, the reduction is performed on 100 data points, and the ratio of sample components is calculated in real time. can be reliably and repeatedly measured sample by sample in rapid succession for on-line monitoring. configured and arranged so that system. 2. The basic magnetic field applying coil means stabilizes the rough heat of the external sample processing area and stabilizes the coil poles. A Helmholtz coil that produces an intermediate stability of the internal sample holding area adjacent to the surface. means for maintaining resonance in the sample region and the sample region; Claims include a coarse thermal environment coil for fine adjustment due to changes in electromagnetic field to maintain The system described in paragraph 1. 3. Another way to deal with thermally induced drift is by adjusting the extracted attenuated signal. 3. The system according to claim 2, further comprising means for performing the operation. 4. The adjustment means for the extracted attenuation signal is configured to adjust at least the area product of the discrete function components. 4. The method according to claim 3, further comprising means for performing said analysis of the free induction decay curve in terms of minutes. system. 5. said means for performing said analysis simultaneously with or in conjunction with the excitation time causing the attenuation; of the bound and unbound components of the decay curves for the associated reconstructed time zero intercepts. 2. The system of claim 1 which produces expansion. 6. Virtually free of sample attenuation resulting in components associated with the sensitivity of the measurements performed 2. The system of claim 1, further comprising a sample container. 7. 7. The system of claim 6, wherein the sample container is a fluorocarbon tube. . 8. 7. The system of claim 6, wherein said sample container is a ceramic tube. Mu. 9. 7. The system of claim 6, wherein said sample container is a glass tube. 10. A system according to claim 1, configured for measuring moisture. 11. A claim configured to detect the ratio of amorphous and crystalline components of a mixture. The system described in Scope 1. 12. Extend each of the many attenuation curves with Hahn spin-echo refocusing/attenuation and related to another subcomponent of the sample to enhance the accuracy of the ratio determination in (c) above. Providing a means to capture data and/or identify proportions of different subcomponents. The system of claim 1 further comprising: 13.2π refocusing pulse The system according to claim 12 added for the generation of Hahn spin echoes. Tem. 14. The plot at the exact zero-axis intercept can be related to the original intercept of the free induction decay curve. Claim further providing means for determining a time window for operating the detection of pin echoes The system according to item 12. 15. Determination of the time window and free induction reduction by off-resonance comparison It is requested that there be further means for compensating the attenuation of the spin echo response with respect to the initial response of the attenuation. The system according to item 14. 16. 13. The system of claim 12, configured to produce proportionality. 17. 13. The system of claim 12 configured to produce a crystalline output. Mu. 18. 13. The system of claim 12, configured to produce a moisture output. . 19. 13. The system of claim 12, configured to produce a density output. .