GB2149509A - Controlling nuclear magnetic resonance analysis - Google Patents
Controlling nuclear magnetic resonance analysis Download PDFInfo
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- GB2149509A GB2149509A GB08330237A GB8330237A GB2149509A GB 2149509 A GB2149509 A GB 2149509A GB 08330237 A GB08330237 A GB 08330237A GB 8330237 A GB8330237 A GB 8330237A GB 2149509 A GB2149509 A GB 2149509A
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R33/00—Arrangements or instruments for measuring magnetic variables
- G01R33/20—Arrangements or instruments for measuring magnetic variables involving magnetic resonance
- G01R33/44—Arrangements or instruments for measuring magnetic variables involving magnetic resonance using nuclear magnetic resonance [NMR]
- G01R33/46—NMR spectroscopy
- G01R33/4625—Processing of acquired signals, e.g. elimination of phase errors, baseline fitting, chemometric analysis
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- Spectroscopy & Molecular Physics (AREA)
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- Condensed Matter Physics & Semiconductors (AREA)
- General Physics & Mathematics (AREA)
- Magnetic Resonance Imaging Apparatus (AREA)
Abstract
In a method of analysis a weighed sample, nuclear magnetic resonance (NMR) signals are obtained therefrom during a succession of measuring cycles. During each cycle, computation is made of the mean value of the NMR signals and of a standard deviation thereof. The standard deviation is subtracted from a permissible limiting standard deviation value and the signal accumulation is stopped when the difference is positive. This is followed by the steps of computing a mean value of the NMR signals and determining percentage of components in the analyzed sample with regard to its mass and the mean value of the NMR signals. The method is primarily intended for analyzing on a mass scale oil seeds and associated processed products to determine a fat and water content.
Description
SPECIFICATION
Method of quantitative analysis of substances and nuclear-resonant quantitative analyzer therefor
The invention relates to radiospectroscopy and in particular to a method of quantitative analysis of substances and a nuclear-resonant quantitative analyzer therefor.
The invention may be used for a quantitative analysis of various substances to determine a fat or water content, a solid phase content in fats, petroleum products, analysis of polymers, etc., and measurement of times of spin-spin and spin-lattice nuclear magnetic relaxations of these substances. It may be used to advantage in analyzing on a mass scale oil seeds and associated processed products to determine a fat or water content.
The invention resides in providing a method of quantitative analysis of substances based on utilization of a nuclear magnetic resonance phenomenon, which would automatically ensure a choice of an optimum number of measuring cycles for a given analysis and simultaneously enhance a measuring accuracy, a feature making it possible to decrease an analyzing time, another object being provision of a nuclear resonant quantitative analyzer for accomplishing the proposed method.
There is provided a method of quantitative analysis of substances based on the utilization of a nuclear magnetic resonance phenomenon and comprising the steps of weighing a sample of substance to be analyzed, obtaining therefrom and accumulating nuclear magnetic resonance signals during n measuring cycles, computing a mean value of the NMR signals and determining percentage of components in the sample under test with regard to its mass and the mean value of the NMR signals, in which, according to the invention, the mean value of the NMR signals accumulated by the present measuring moment and a standard deviation thereof are computed during signal accumulation in each of then measuring cycles, the subsequent step being subtraction of the standard deviation from a permissible limiting standard deviation value set before the analysis to obtain a desired analyzing accuracy whereupon the signal accumulation is stopped in the n thcycle, in which a difference between said magnitudes is a positive value.
There is also provided a nuclear-resonant quantitative analyzer comprising a magnetic system, a nuclear magnetic resonance signal pick-up arranged in its gap, an amplifier, a selector and an analog-to-digital converter being placed in series and connected to the output of said pick-up whose input is connected to such series-connected components as a video-pulse generator having its second output connected to a second input of the selector and a radio-pulse generator, and a data output unit coupled via its inputs to the outputs of the analog-to-digital converter, which, according to the invention, additionally comprises an automatic sample weighing unit composed of such series-connected components as a weight-to-frequency converter whose load-receiving platform is inserted in the NMR signal pick-up and a frequency-to-code converter, a data swapping unit, a processor, a control unit, a programming unit comprising a control circuit and a memory, which generates a sequence of instructions controlling the processor, the data swapping unit and the control unit and ensures storage of sample mass codes and the NMR signals from the sample in an on-line memory of the processor, signal accumulation during n cycles, calculation of the mean value of the obtained NMR signals and a standard deviation in each of the n cycles, subtraction of the standard deviation from a permissible limiting standard deviation value, stoppage of the signal accumulation during thenith cycle, in which a difference between said magnitudes is a positive value, and computation of percentage of components in the sample with regard to its mass and the mean value of the NMR signals therefrom, the inputs of the data swapping unit being connected to the outputs of respective bits of the analog-to-digital converter, the frequency-to-code converter and the processor, while the outputs of the data swapping unit are connected to the data inputs of respective bits of the processor and the data output unit, the instruction outputs of the programming unit being connected to respective instruction inputs of the processor, a first control output of the programming unit being connected to the control input of the data output unit, a second control output of the programming unit being connected to the first input of the control unit whose second input is connected to the first output of the processor, while the first input of the programming unit is connected to the second output of the processor, two outputs of the control unit being connected to the control inputs of the analogl-to-digital and frequency-to-code converters.
To provide for automatic correction of analysis results when parameters of the equipment are changed, the nuclear resonant quantitative analyzer forming the subject of the invention preferably includes such an additional means as a pick-up indicating presence of an analyzed sample in the NMR signal pick-up, which is connected via its output to a third input of the control unit whose output is, in turn, connected to the second input of the programming unit having an additional memory file controlled by said input, which ensures generation of a sequence of instructions controlling the processor to determine a correction factor with regard to the current mean value of a signal from a referene sample and the value of said signal at the analyzer calibration instant, arranged in the on-line memory of the processor.
The proposed method of quantitative analysis of substances based on utilization of a nuclear magnetic resonance phenomenon makes it possible to appreciably increase an analyzing accuracy and decrease the analysis time, which is an apparent advantage over the prior art. The nuclear-resonant quantitative analyzer for accomplishing the proposed method permits making the analyzing process fully automatic, other advantages being enhanced accuracy and reduced analysis time. Moreover, it is simple to manufacture and may employ semi-conductor devices and completing items which are widely used at the present time.
The invention will now be described further with reference to specific embodiments thereof, taken in conjunction with the accompanying drawing which is a block diagram of a nuclear-resonant quantitative analyzer
The method of quantitative analysis of substances based on utilization of a nuclear magnetic resonance phenomenon comprises the following operations. A sample to be analyzed is weighed, its mass is recorded and simultaneously NMR signals are obtained therefrom.Upon receipt of each NMR signal, that is, in each measuring cycle, the mean value of all previously obtained signals and a standard deviation thereof are computed from the formula
where S( ) = evaluation of standard deviation of the mean value of the signals;
A = mean signal value; Xi = value of the ith signal; and
n = number of signals accumulated by the present measuring moment (number of measuring cycles)
Thereafter the value S(A) is subtracted from the permissible limiting standard deviation value S(A)o, which is determined before the analysis by the formula S(A)0= .t-1 where
F = permissible limiting value of a random component of a measuring error; and
t = Student coefficient for a given level of confidence.
Stated differently, the two values are compared and the accumulation is continued if
S(A) > S(A)o The accumulation is stopped during the ni'h cycle when S(A)o exceeds S(A) and the difference therebetween is a positive value.
Percentage of components in the sample under test is determined with regard to its mass and the mean value of the NMR signals from the sample using the known relationship between the value of the NMR signal and the amount of the tested component.
A random component of a measuring error does not exceed F for a given level of confidence.
The proposed method of quantitative analysis of substances based on utilization of a nuclear magnetic resonance phenomenon is accomplished by the use of the nuclear-resonant quantitative analyzer shown in the accompanying drawing. The analyzer is designed for determining percentage of fat and water in oil seeds and associated processed products.
Referring to the drawing the nuclear-resonant quantitative analyzer comprises a NMR signal pick-up 1 arranged in a gap of a magnetic system 2, a video-pulse generator3 and a radio-pulse generator 4 whose output is connected to the input of the NMR signal pick-up 1, while its input is connected to the output of the video-pulse generator 3. The analyzer also comprises such series-connected components as a NMR signal amplifier 5, a selector 6 and an analog-to-digital converter 7, the input of the amplifier 5 being connected to the output of the NMR signal pick-up 1, while the second input of the selector 6 is connected to the second output of the video-pulse generator 3.Besides, the analyzer comprises such series-connected components as a weight-to-frequency converter 8 and a frequency-to-code converter 9, a load-receiving platform of the weight-to-frequency converter 8 being inserted in the lower portion of the cylindrical cavity of the form of an inductance coil of the NMR signal pick-up 1 (not shown in the drawing). The NMR signal pick-up 1 also includes a permanently arranged calibration sample possessing a stable characteristic.
The nuclear-resonant quantitative analyzer also comprises a data swapping unit 10 having m inputs in each bit, a processor 11, a control unit 12, a programming unit 13 including a control circuit and two memory files, a data output unit 14, and a pick-up 15 indicating presence of the analyzed sample in the NMR pick-up 1, which is connected via its output to an input 16 of the control unit 12. The inputs of the data swapping unit 10 are connected to the output of respective bits of the analog-to-digital converter 7, the frequency-to-code converter 9, and the processor 11. Outputs 17 of the data swapping unit are connected to the data inputs of respective bits of the processor 11 and the data output unit 14. Instruction outputs 18 of the programming unit 13 are connected to the instruction inputs of the processor 11, while an output 19 of the programming unit 13 is connected to a control input 20 of the data output unit 14, an output 21 of the programming unit 13 being connected to an input 22 of the control unit 12 having its input 23 connected to an output 24 of the processor 11, an input 25 of the programming unit 13 being connected to an output 26 of the processor 11.
Two outputs 27 and 28 of the control unit 12 are, respectively, connected to the control inputs of the analog-to-digital converter 7 and the frequency-to-code converter 9, an output 29 of the control unit 12 being connected to an input 30 of the programming unit 13. The magnetic system 2 may comprise an electromagnet or a permanent magnet including an NMR-signal induction stabilizer for a magnetic field in the working gap. The NMR signal pickup 1 may use a single-coil circuit with a ratio of winding length to its diameter being at least 1.5. The units 3,4,5,6,7,9, and 12 may employ readily available AND, OR and NOT gates, flip-flops, counters, operational amplifiers, transistors and the like.The weight-to-frequency converter 8 may include two converting means for weight-to-linear-displacement conversion and linear-displacementto-frequency conversion, said means being fabricated from suitable nonmagnetic materials. The data swapping unit 10 may use multiplexers. It is also of advantage that the programming unit 13 should use re-programmable permanent memories with electrically swapped data and long retention thereof with power supplies being turned off or on. It is also advantageous that the processor 11 should use highly integrated microcircuits, the data output unit 14 being provided with light-emitting elements and an alphanumeric printer.
Desirably the pick-up 15 is a photosensor with a photoresistorand a light source.
The method of quantitative analysis of substances based on utilization of a nuclear magnetic resonance and realized in the preferred device will become more apparent from the description of the analyzer operation which, is as follows.
The operating cycle of the analyzer includes two modes: a "correction" mode and an "analyzing" mode.
The operation starts in the "correction" mode on activation of the "start" buttons when a sample to be analyzed is not yet placed in the N MR signal pick-up 1. A logic "0" signal is applied from the output of the pick-up 15 indicating presence of the analyzed sample in the NMR signal pick-up 1 to the input 16 of the control unit 12. Control signals from the output 29 of said unit are fed to the input 30 of the programming unit 13. Upon receipt of these signals, the programming unit 13 addresses locations of the memory file storing the codes of the instructions controlling the processor 11, the data swapping unit 10, the control unit 12 and the data output unit 14 in the "correction" mode.Simultaneously the video-pulse generator 3 generates a train of video pulses Tr 2, - TF - .., which come to the input of the radio-pulse generator 4, gating pulses being also furnished by the video-pulse generator. From the output of the radio-pulse generator 4 the train of radio-pulses 7F12 TrTr... is fed to the input of the NMR signal pick-up 1. From the output of the NMR signal pick-up 1 free-precession signals and spin echo signals from the calibration sample permanently found in the inductance coil 1 of the NMR signal pick-up 1 are applied to the input of the NMR signal amplifier 5, wherein they are amplified and detected.From the amplifier output said signals are fed to the input of the selector 6 whose second input accepts the gating pulses from the second output of the video-pulse generator. From the output of the selector 6 the video pulses having their amplitude equal to the amplitude of the NMR signals are delivered to the input of the analog-to-digital converter 7. From the output of said converter numeric codes of the NMR signal amplitudes are supplied to the inputs of the data swapping unit 10. At the time the NMR signals are received from the calibration sample, the weight-to frequency converter 8 furnishes a signal corresponding to "zero" weight (no sample is analyzed), said signal being applied to the input of the frequency-to-code converter 9. From the outputs of said converter a "zero" weight code is supplied to the other inputs of the data swapping unit 10.
In response to the signals from the control unit 12, the data swapping unit 10 transmits the NMR signal codes from the calibration sample and the "zero" weight code to the on-line memory of the processor 11 which, in response to the instruction signals from the programming unit 12 coming to the instruction inputs of the processor 11 stores the NMR signals, computes their mean value and a standard deviation S( ) and compares S( ) with S( )o. When the condition S( ) S S(A)o is satisfied, the accumulation process is terminated.Next, a correction factor is calculated by the formula
K = Ac.sDAci 1 where K= correction factor; Acs = value of the NMR signal from the calibration sample at the analyzer calibration moment; and Ac = value of the current NMR signal from the calibration sample.
The "zero" weight code is used to compute a correction: Ap = Apo - Apj
whereAp = correction; Apo = "zero" weight code atthe analyzer calibration moment; and Ap = current "zero" weight code.
After the correction factor K and the correction Ap have been determined, their values are stored in locations of the on-line memory of the processor 11, and the output 19 of the programming unit 13 develops an"end-of-correction" signal which is fed to the data output unit 14 wherein it is appropriately displayed.
Simultaneously an"end-of-mode" signal is applied from the output 21 of the programming unit 13 to the input 22 of the control unit 12 whose outputs 27 and 28 develop resetting signals for the analog-to-digital converter and the frequency-to-code converter 9. The "correction" mode is, thus, terminated.
The "analyzing" mode begins automatically after a sample to be analyzed is placed in the NMR signal pick-up 1.
A logic "1" signal is applied from the output of the pick-up 15 to the input 16 of the control unit 12. From the output 29 of said unit an "analysis" signal is fed to the input of the programming unit 13. Another
memory file is, thus, addressed. Said file shapes control signals and instructions to provide operation in the "analyzing" mode. The "end-of-correction" indication will be no longer present on the panel of the unit 14, and the "analysis" indication will also disappear. The NMR signals from the calibration sample and from the sample under test are amplified, gated, converted into a numeric code and applied to the inputs of the data swapping unit 10 in much the same manner as in the "correction" mode. Similarly, the other inputs of said unit accept the sample weight code furnished by the frequency-to-code converter 9 using the signals of the weight-to-frequency converter 8.
In response to the signals from the control unit 12 and the programming unit 13 delivered to the data swapping unit 10 and the processor 11, the NMR signal codes and the sample weight code are received by the processor 11 wherein they are adjusted by multiplying the corresponding values into the correction factor K, the correction Ap being added up, accordingly. Thereafter the corrected NMR signal codes are stored, and computation is made of their mean value and the magnitude S(A). The signal accumulation ends during the n fh cycle when S( ) S S(A)o Next, the mean value of the NMR signals and the sample weight code are used to compute, referring to the known relationships, the amount of fat and water in the analyzed sample and relevant percentage.The analysis result codes are supplied from the outputs of the processor 11 to the inputs of the data swapping unit 10 and from its outputs to the inputs of the data output unit 14. The analysis results are displayed and printed. This ends the "analyzing" mode.
The nuclear-resonant quantitative analyzer forming the subject of the invention makes it possible to automatically weight a sample to be analyzed simultaneously with delivery of NMR signals from the sample, another advantage being automatic processing of the obtained information. A desired analyzing accuracy is provided with a minimum NMR signal accumulation time, the proposed analyzer operating without any adjustments. The analyzing accuracy is not dependent upon the operator's skill.
The use of the proposed nuclear-resonant quantitative analyzer in oil-and-fat industries and agriculture makes it possible to make labour and material requirements for analyzing operations less stringent, to select lots of seeds for storage and processing with due regard for qualitative indices, said selection being made more efficient, to determine optimum times for processing oil seeds, to increase production of high-standard oil and the oil output.
Claims (5)
1. A method of quantitative analysis of substances based on utilization of a nuclear magnetic resonance phenomenon and comprising the steps of weighing a sample of substance to be analyzed, obtaining therefrom and accumulating nuclear magnetic resonance (NMR) signals during n measuring cycles, computing a mean value of the NMR signals and determining percentage of components in the analyzed sample with regard to its mass and the mean value of the NMR signals from said sample, the mean value of the NMR signals accumulated by the present measuring moment and a standard deviation thereof being computed during signal accumulation in each of the n measuring cycles, the subsequent step being subtraction of the mean standard deviation from a permissible limiting standard deviation value set before the analysis to obtain a desired analyzing accuracy whereupon the signal accumulation is stopped during the njth measuring cycle, in which a difference between said magnitudes is a positive value.
2. A nuclear-resonant quantitative analyzer comprising a magnetic system, a NMR signal pick-up arranged in its gap, an amplifier, a selector and an analog-to-digital converter, which are placed in series and connected to the output of said pick-up, a video-pulse generator having its second output coupled to a second input of the selector and a radio-pulse generator, which are placed in series and connected to the input of the analog-to-digital converter, a data output unit connected via its inputs to the outputs of the analog-to-digital converter, an automatic sample weighing unit composed of such series-connected components as a weight-tofrequency converter whose load-receiving platform is inserted in the NMR signal pickup and a frequency-to-code converter, a data swapping unit, a processor, a control unit, a programming unit comprising a control circuit and a memory and generating a sequence of instructions controlling the processor, the data swapping unit and the control unit, said programming unit being also used to ensure storage of mass and sample codes and NMR signals from the sample in an on-line memory of the processor, accumulation of said signals during n measuring cycles, computation of a mean value of the obtained NMR signals and a standard deviation thereof in each of the n measuring cycles, subtraction of the standard deviation from a permissible limiting standard deviation value, stoppage of the signal accumulation during the njth measuring cycle, in which a difference between said magnitudes is a positive value, and determination of percentage of components in the sample with regard to its mass and the mean value of the
NMR signals therefrom, the inputs of the data swapping unit being connected to the outputs of respective bits of the analog-to-digital converter, the frequency-to-code converter and the processor, while the outputs of the data swapping unit are connected to the data inputs of respective bits of the processor and the data output unit, the instruction outputs of the programming unit being connected to the respective instruction inputs of the processor, the first control output of the programming unit being connected to the control input of the data output unit, while the second control output of the programming unit is coupled to the first input of the control unit whose second input is connected to the first output of the processor, the first input of the programming unit being connected to the second output of the processor, two outputs of the control unit being connected to the control inputs of the analog-to-digital converter and the frequency-to-code converter.
3. A nuclear-resonant quantitative analyzer as claimed in Claim 2, which additionally comprises a pick-up indicating presence of the analyzed sample in the NMR signal pick-up and having an output connected to the third input of the control unit whose output is, in turn, connected to the second input of the programming unit having an additional memory file controlled by said input, which ensures generation of a sequence of instructions controlling the processor to compute a correction factor with respect to the current mean value of a signal from a reference sample and the value of said signal at the analyzer calibration instant, arranged in the on-line memory of the processor.
4. A method of quantitative analysis of substances substantially as hereinabove described in Claim 1 and in the patent specification.
5. A nuclear-resonant quantitative analyzer substantially as hereinabove described in Claims 2,3 and in the patent specification with reference to, and as shown in the accompanying drawing.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB08330237A GB2149509B (en) | 1983-11-12 | 1983-11-12 | Controlling nuclear magnetic resonance analysis |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB08330237A GB2149509B (en) | 1983-11-12 | 1983-11-12 | Controlling nuclear magnetic resonance analysis |
Publications (3)
| Publication Number | Publication Date |
|---|---|
| GB8330237D0 GB8330237D0 (en) | 1983-12-21 |
| GB2149509A true GB2149509A (en) | 1985-06-12 |
| GB2149509B GB2149509B (en) | 1987-04-01 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB08330237A Expired GB2149509B (en) | 1983-11-12 | 1983-11-12 | Controlling nuclear magnetic resonance analysis |
Country Status (1)
| Country | Link |
|---|---|
| GB (1) | GB2149509B (en) |
Cited By (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO1999067606A1 (en) * | 1998-06-24 | 1999-12-29 | Scientific Generics Limited | Check weighing apparatus and method |
| US6946838B2 (en) | 2003-05-16 | 2005-09-20 | The Boc Group, Inc. | NMR measuring system |
| US7002346B2 (en) | 2004-05-03 | 2006-02-21 | The Boc Group, Inc. | Method for accurate determination of sample temperature in a NMR check weighing system |
| US7008486B2 (en) | 2003-05-16 | 2006-03-07 | The Boc Group, Inc. | Cleaning method for NMR check weighing system |
| US7015693B2 (en) | 2003-05-16 | 2006-03-21 | The Boc Group, Inc. | NMR measuring system for weight and humidity of powders |
| US7041914B2 (en) | 2004-05-04 | 2006-05-09 | The Boc Group, Inc. | Method for compensation of near-neighbor sample effects in a NMR check weighing system |
| US7061239B2 (en) | 2004-04-30 | 2006-06-13 | The Boc Group, Inc. | Method for magnetic field tracking in a NMR check weighing system |
| US7064548B2 (en) | 2004-04-30 | 2006-06-20 | The Boc Group, Inc. | RF probe apparatus for NMR check weighing system |
| US7084627B2 (en) | 2004-04-30 | 2006-08-01 | The Boc Group, Inc. | Method for triggering NMR measurement in a NMR check weighing system |
| US7199581B2 (en) | 2003-05-16 | 2007-04-03 | The Boc Group, Inc. | Magnetic resonance measuring system determining the mass of samples in a production line with monitored drift compensation |
| EP2315085A1 (en) * | 2009-10-26 | 2011-04-27 | Bruker Biospin | Device for correcting set points and gradient generation system comprising such a device |
| EP2969268A4 (en) * | 2013-03-15 | 2017-01-11 | Monsanto Technology LLC | High-throughput sorting of small objects via oil and/or moisture content using low-field nuclear magnetic resonance |
-
1983
- 1983-11-12 GB GB08330237A patent/GB2149509B/en not_active Expired
Cited By (16)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| AU748784B2 (en) * | 1998-06-24 | 2002-06-13 | Scientific Generics Limited | Check weighing apparatus and method |
| US6759601B1 (en) | 1998-06-24 | 2004-07-06 | Scientific Generics Limited | Check weighing apparatus and method |
| WO1999067606A1 (en) * | 1998-06-24 | 1999-12-29 | Scientific Generics Limited | Check weighing apparatus and method |
| US6946838B2 (en) | 2003-05-16 | 2005-09-20 | The Boc Group, Inc. | NMR measuring system |
| US7008486B2 (en) | 2003-05-16 | 2006-03-07 | The Boc Group, Inc. | Cleaning method for NMR check weighing system |
| US7015693B2 (en) | 2003-05-16 | 2006-03-21 | The Boc Group, Inc. | NMR measuring system for weight and humidity of powders |
| US7199581B2 (en) | 2003-05-16 | 2007-04-03 | The Boc Group, Inc. | Magnetic resonance measuring system determining the mass of samples in a production line with monitored drift compensation |
| US7084627B2 (en) | 2004-04-30 | 2006-08-01 | The Boc Group, Inc. | Method for triggering NMR measurement in a NMR check weighing system |
| US7061239B2 (en) | 2004-04-30 | 2006-06-13 | The Boc Group, Inc. | Method for magnetic field tracking in a NMR check weighing system |
| US7064548B2 (en) | 2004-04-30 | 2006-06-20 | The Boc Group, Inc. | RF probe apparatus for NMR check weighing system |
| US7002346B2 (en) | 2004-05-03 | 2006-02-21 | The Boc Group, Inc. | Method for accurate determination of sample temperature in a NMR check weighing system |
| US7041914B2 (en) | 2004-05-04 | 2006-05-09 | The Boc Group, Inc. | Method for compensation of near-neighbor sample effects in a NMR check weighing system |
| EP2315085A1 (en) * | 2009-10-26 | 2011-04-27 | Bruker Biospin | Device for correcting set points and gradient generation system comprising such a device |
| FR2951835A1 (en) * | 2009-10-26 | 2011-04-29 | Bruker Biospin | DEVICE FOR CORRECTING SET SIGNALS AND GRADIENT GENERATION SYSTEM COMPRISING SUCH A DEVICE |
| US8736268B2 (en) | 2009-10-26 | 2014-05-27 | Bruker BioSpin S.A.S. | Device for correcting set-point signals and system for the generation of gradients comprising such a device |
| EP2969268A4 (en) * | 2013-03-15 | 2017-01-11 | Monsanto Technology LLC | High-throughput sorting of small objects via oil and/or moisture content using low-field nuclear magnetic resonance |
Also Published As
| Publication number | Publication date |
|---|---|
| GB2149509B (en) | 1987-04-01 |
| GB8330237D0 (en) | 1983-12-21 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PCNP | Patent ceased through non-payment of renewal fee |
Effective date: 19921112 |