CN112649459A - Time-domain nuclear magnetic resonance-based composite material component content determination method and system - Google Patents
Time-domain nuclear magnetic resonance-based composite material component content determination method and system Download PDFInfo
- Publication number
- CN112649459A CN112649459A CN201910966273.4A CN201910966273A CN112649459A CN 112649459 A CN112649459 A CN 112649459A CN 201910966273 A CN201910966273 A CN 201910966273A CN 112649459 A CN112649459 A CN 112649459A
- Authority
- CN
- China
- Prior art keywords
- content
- signal intensity
- composite material
- magnetic resonance
- nuclear magnetic
- 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.)
- Pending
Links
- 239000002131 composite material Substances 0.000 title claims abstract description 86
- 238000005481 NMR spectroscopy Methods 0.000 title claims abstract description 64
- 238000000034 method Methods 0.000 title claims abstract description 29
- 238000001228 spectrum Methods 0.000 claims abstract description 32
- 238000012360 testing method Methods 0.000 claims abstract description 17
- 239000007787 solid Substances 0.000 claims description 11
- 125000004435 hydrogen atom Chemical group [H]* 0.000 claims description 9
- 230000002238 attenuated effect Effects 0.000 claims description 4
- 125000004122 cyclic group Chemical group 0.000 claims description 4
- 239000000523 sample Substances 0.000 description 33
- VTYYLEPIZMXCLO-UHFFFAOYSA-L Calcium carbonate Chemical compound [Ca+2].[O-]C([O-])=O VTYYLEPIZMXCLO-UHFFFAOYSA-L 0.000 description 29
- 229910000019 calcium carbonate Inorganic materials 0.000 description 14
- 239000004707 linear low-density polyethylene Substances 0.000 description 13
- 229920000092 linear low density polyethylene Polymers 0.000 description 11
- CDBYLPFSWZWCQE-UHFFFAOYSA-L Sodium Carbonate Chemical compound [Na+].[Na+].[O-]C([O-])=O CDBYLPFSWZWCQE-UHFFFAOYSA-L 0.000 description 10
- 239000004700 high-density polyethylene Substances 0.000 description 9
- 239000000463 material Substances 0.000 description 9
- 239000004701 medium-density polyethylene Substances 0.000 description 9
- 229920001903 high density polyethylene Polymers 0.000 description 8
- 229920001179 medium density polyethylene Polymers 0.000 description 8
- 238000005070 sampling Methods 0.000 description 8
- 238000005259 measurement Methods 0.000 description 7
- 239000000203 mixture Substances 0.000 description 6
- 238000002474 experimental method Methods 0.000 description 5
- 229910000029 sodium carbonate Inorganic materials 0.000 description 5
- 239000003153 chemical reaction reagent Substances 0.000 description 4
- 239000002245 particle Substances 0.000 description 4
- 229920000642 polymer Polymers 0.000 description 4
- 239000000126 substance Substances 0.000 description 4
- 239000011256 inorganic filler Substances 0.000 description 3
- 229910003475 inorganic filler Inorganic materials 0.000 description 3
- 229920010126 Linear Low Density Polyethylene (LLDPE) Polymers 0.000 description 2
- 238000004458 analytical method Methods 0.000 description 2
- 238000001514 detection method Methods 0.000 description 2
- 239000002861 polymer material Substances 0.000 description 2
- 238000000197 pyrolysis Methods 0.000 description 2
- 238000004064 recycling Methods 0.000 description 2
- 238000010998 test method Methods 0.000 description 2
- -1 Polyethylene Polymers 0.000 description 1
- 239000004698 Polyethylene Substances 0.000 description 1
- 241000135164 Timea Species 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 239000003814 drug Substances 0.000 description 1
- 239000000945 filler Substances 0.000 description 1
- 238000009472 formulation Methods 0.000 description 1
- 230000005484 gravity Effects 0.000 description 1
- 230000005283 ground state Effects 0.000 description 1
- 229910003480 inorganic solid Inorganic materials 0.000 description 1
- 239000007769 metal material Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000001225 nuclear magnetic resonance method Methods 0.000 description 1
- 229920000573 polyethylene Polymers 0.000 description 1
- 230000003252 repetitive effect Effects 0.000 description 1
- 230000007704 transition Effects 0.000 description 1
- 239000002699 waste material Substances 0.000 description 1
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N24/00—Investigating or analyzing materials by the use of nuclear magnetic resonance, electron paramagnetic resonance or other spin effects
- G01N24/08—Investigating or analyzing materials by the use of nuclear magnetic resonance, electron paramagnetic resonance or other spin effects by using nuclear magnetic resonance
- G01N24/082—Measurement of solid, liquid or gas content
Landscapes
- Physics & Mathematics (AREA)
- High Energy & Nuclear Physics (AREA)
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Chemical & Material Sciences (AREA)
- Analytical Chemistry (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- General Physics & Mathematics (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Other Investigation Or Analysis Of Materials By Electrical Means (AREA)
Abstract
The invention provides a method and a system for measuring the component content of a composite material based on time-domain nuclear magnetic resonance, wherein the method comprises the following steps: s1 obtaining nuclear magnetic resonance T of the composite material with known content of n components2Establishing a standard curve of signal intensity and component content at a specific time point according to the spectrum; s2, obtaining nuclear magnetic resonance T of the sample to be detected2Recording the spectrum and the signal intensity at the specific time point as a first signal intensity; and S3, calculating the component content of the sample to be detected according to the standard curve and the first signal intensity. The system comprises a curve establishing unit, a signal intensity acquiring unit and a content calculating unit. The method does not need to damage the sample, and has short time consumption and high accuracy in the testing process.
Description
Technical Field
The invention relates to the field of composite material component content detection, in particular to a composite material component content determination method and system based on time domain nuclear magnetic resonance, which can be used for rapidly and quantitatively determining the content of an inorganic filler in a high molecular polymer.
Background
Among various materials currently used by humans, a composite material in which different types of materials are mixed together by various methods occupies a very large specific gravity. In the composite material, the composite material formed by mixing the inorganic non-metallic material and the high polymer material is the composite material with the largest use amount. Since the amount of the composite material used is large, the amount of waste generated therefrom is also large, and recycling thereof naturally becomes a subject of great attention in the industry. One method of recycling composite materials is to separate the different components of the composite material for reuse. The method needs to know the content of each component in the recycled composite material, and the existing method for detecting the content of each component in the composite material is mainly a pyrolysis analysis method, the high temperature used by the method can damage a sample, and the method needs a longer time for testing.
Disclosure of Invention
Features and advantages of the invention will be set forth in part in the description which follows, or may be obvious from the description, or may be learned by practice of the invention.
The invention provides a method and a system for determining the component content of a composite material based on time-domain nuclear magnetic resonance, the method is suitable for detecting the component content in the composite material, and is particularly suitable for determining the content of an inorganic filler in a high molecular polymer.
The technical scheme adopted by the invention for solving the technical problems is as follows:
according to one aspect of the invention, a composite material component content determination method based on time-domain nuclear magnetic resonance is provided, which comprises the following steps:
s1 obtaining nuclear magnetic resonance T of the composite material with known content of n components2Establishing a standard curve of signal intensity and component content at a specific time point according to the spectrum;
s2, obtaining nuclear magnetic resonance T of the sample to be detected2Recording the spectrum and the signal intensity at the specific time point as a first signal intensity;
and S3, calculating the component content of the sample to be detected according to the standard curve and the first signal intensity.
Optionally, the establishing of the standard curve of signal intensity and component content at a specific time point specifically includes:
obtaining composites with known content of n componentsNuclear magnetic resonance T2Signal intensity at a particular point in time in the spectrum;
acquiring the content of a certain component of the composite material with known content of n components;
and fitting to obtain a standard curve according to the signal intensity and the content of a certain component.
Optionally, the standard curve is: y is ax + b; wherein y is the content of the hydrogen atom-containing component in the composite material, and x is the signal intensity.
Optionally, n is any natural number from 2 to 50.
Optionally, the step S1 includes obtaining corresponding nmr T by measuring the composite material with n known component contents on a time domain nmr using a solid echo sequence2A spectrum; wherein:
the parameter settings of the solid echo sequence comprise at least one of: the scanning times are set to be between 4 and 128 times; the cyclic waiting time is set to be 0.5-50 seconds; the gain value is set to be determined according to an actual sample according to the principle that data do not overflow during testing; the First time interval (First Duration) is the shortest time value defined by the solid echo sequence, and the final time interval (Last Duration) is the nuclear magnetic resonance T2When the spectrum is attenuated to 0, the corresponding time value is 4-8 times; the number of data points is set between 2 and 200.
According to another aspect of the present invention, there is provided a composite material component content determination system based on time-domain nuclear magnetic resonance, comprising:
a curve establishing unit for obtaining the nuclear magnetic resonance T of the composite material with known content of n components2Establishing a standard curve of signal intensity and component content at a specific time point according to the spectrum;
a signal intensity acquisition unit for acquiring nuclear magnetic resonance T of the sample to be measured2Recording the spectrum and the signal intensity at the specific time point as a first signal intensity;
and the content calculation unit is used for calculating the component content of the sample to be detected according to the standard curve and the first signal intensity.
Optionally, the curve establishing unit is specifically configured to:
obtaining NMR T of composite material with known content of n components2Signal intensity at a particular point in time in the spectrum;
acquiring the content of a certain component of the composite material with known content of n components;
and fitting to obtain a standard curve according to the signal intensity and the content of a certain component.
Optionally, the standard curve is: y is ax + b; wherein y is the content of the hydrogen atom-containing component in the composite material, and x is the signal intensity.
Optionally, n is any natural number from 2 to 50.
The present invention also provides a computer-readable storage medium storing at least one program executable by a computer, the at least one program, when executed by the computer, causing the computer to perform the steps of the method provided by any of the embodiments of the present invention.
Compared with the existing pyrolysis analysis test method, the test method provided by the invention does not need to damage the sample, and is short in time consumption and high in accuracy in the test process.
The features and content of these solutions will be better understood by those skilled in the art from reading the present description.
Drawings
The advantages and realisation of the invention will be more apparent from the following detailed description, given by way of example, with reference to the accompanying drawings, which are given for the purpose of illustration only, and which are not to be construed in any way as limiting the invention, and in which:
fig. 1 is a schematic flow chart of a method for determining a content of a component in a composite material based on time-domain nuclear magnetic resonance in an embodiment of the present invention.
Fig. 2 is a schematic structural diagram of a composite material component content determination system based on time-domain nuclear magnetic resonance in an embodiment of the invention.
FIG. 3 shows the content T of Linear Low Density Polyethylene (LLDPE) in the calcium carbonate composite of example 1 of the present invention and LLDPE2A plot of a fitted standard curve of the signal intensity of the decay curve at 0.025 ms.
FIG. 4 shows the MDPE content and T in the composite of Medium Density Polyethylene (MDPE) and calcium carbonate in example 2 of the present invention2A plot of a fitted standard curve of the signal intensity of the decay curve at 0.025 ms.
FIG. 5 shows the HDPE content and T in the composite of high-density polyethylene (HDPE) and calcium carbonate according to example 3 of the present invention2A plot of a fitted standard curve of the signal intensity of the decay curve at 0.025 ms.
FIG. 6 shows the content T of Linear Low Density Polyethylene (LLDPE) in the composite of LLDPE and sodium carbonate in example 4 of the present invention2A plot of a fitted standard curve of the signal intensity of the decay curve at 0.025 ms.
Detailed Description
Time-domain nuclear magnetic resonance has been widely used in the fields of food, geological exploration, agriculture, polymer materials, medicine, etc., as a rapid and nondestructive detection method. The time domain nuclear magnetic resonance principle is that a radio frequency pulse is applied to a sample in a constant magnetic field, so that protons contained in the sample resonate to realize transition from a low energy level to a high energy level, and after the pulse is stopped, the protons in the sample return to a ground state again, and a nuclear magnetic resonance signal is generated. The higher the proton content in the sample, the stronger the nuclear magnetic resonance signal generated. Based on this correlation, the proton content can be inferred by measuring the signal intensity. In a composite material composed of a proton-containing material and a proton-free material, the component contents of the proton-containing material and, consequently, the component contents of the composite material can be deduced by detecting the proton content.
As shown in fig. 1, the present invention provides a method for measuring the component content of a composite material based on time-domain nuclear magnetic resonance, wherein the composite material is a composite material formed by mixing a solid inorganic substance and a substance containing hydrogen atoms, and is preferably a high molecular polymer doped with an inorganic solid filler. The method comprises the following steps:
s1 obtaining nuclear magnetic resonance T of the composite material with known content of n components2Establishing a standard curve of signal intensity and component content at a specific time point according to the spectrum;
wherein n is any natural number from 2 to 50, and n is preferably 7. Generally, the larger the value of n is obtained, the more accurate the standard curve is, but in actual test work, when the value of n is large enough, the accuracy of the standard curve is improved only to a limited extent by increasing the value of n. The value of n should not be too large to avoid too many inefficient repetitive testing efforts. In the embodiment, when the value of n is 7, the standard variance value of the standard curve in the actual test operation has reached the accuracy of 0.0001, so n is preferably 7.
The component content herein is the component content of one component class of the composite material.
Nuclear magnetic resonance T2Spectra can be acquired on a time domain nuclear magnetic resonance instrument using solid echo sequence measurements. The parameter settings of the solid echo sequence comprise at least one of: the scanning times are set to be between 4 and 128 times, and 16 times are preferred; the cyclic waiting time is set to be 0.5-50 seconds, preferably 2 seconds; the gain value is set to be determined according to an actual sample according to the principle that data do not overflow during testing; the First time interval (First Duration) is preferably the shortest time value defined by the solidecho sequence, and the final time interval (Last Duration) is preferably the nuclear magnetic resonance T2When the spectrum is attenuated to 0, the corresponding time value is 4-8 times, preferably 4 times; the number of data points is set between 2 and 200, preferably 2.
Generally, before using a time domain nuclear magnetic resonance apparatus, a standard oil sample is used to correct the instrument parameters such as the center frequency and the pulse width of the time domain nuclear magnetic resonance apparatus.
S2, obtaining nuclear magnetic resonance T of the sample to be detected2Recording the spectrum and the signal intensity at a specific time point as a first signal intensity;
the sample to be tested is the same as the component type of the composite material with known component content, but the content is different. In this step, the samples to be tested are tested for their signal intensity at the same sequence and at the same specific time point.
It should be noted that the selection of a specific time point is not required, and may be any time point on the test curve. In this embodiment, the specific time point is 0.025ms, and this time point is selected because this time point is the starting point of the test curve, where the signal strength is the largest, the signal-to-noise ratio is the largest when the signal strength is the largest, and the accuracy of the test result is the highest.
And S3, calculating the component content of the sample to be detected according to the standard curve and the first signal intensity.
And substituting the first signal intensity into the standard curve to calculate the composition content of the corresponding component type.
In step S1, the establishing of the standard curve of signal intensity and component content at a specific time point specifically includes:
s11 obtaining nuclear magnetic resonance T of the composite material with known content of n components2Signal intensity at a particular point in time in the spectrum;
s12, acquiring the content of a certain component of the composite material with known n component contents; in the present embodiment, this content may be expressed in mass%.
S13, fitting a standard curve according to the signal intensity and the content of a certain component, wherein the standard curve is as follows: y is ax + b; wherein y is the content of the hydrogen atom-containing component in the composite material, and x is the signal intensity.
In specific implementation, the values of a and b are calculated according to the n sets of data acquired in steps S11 and S12, so that the standard curve can be finally determined.
As shown in fig. 2, the present invention provides a time-domain nuclear magnetic resonance-based composite material component content measurement system, which includes a curve establishing unit 10, a signal intensity obtaining unit 20, and a content calculating unit 30.
Wherein:
the curve-establishing unit 10 is used to obtain the NMR T of a composite material with known n component contents2Spectra and establishing therefrom a standard of signal intensity and component content at a particular point in timeA curve; n is any natural number from 2 to 50, preferably 7.
Nuclear magnetic resonance T2Spectra can be acquired on a time domain nuclear magnetic resonance instrument using solid echo sequence measurements. The parameter settings of the solid echo sequence comprise at least one of: the scanning times are set to be between 4 and 128 times, and 16 times are preferred; the cyclic waiting time is set to be 0.5-50 seconds, preferably 2 seconds; the gain value is set to be determined according to an actual sample according to the principle that data do not overflow during testing; the First time interval (First Duration) is preferably the shortest time value defined by the solidecho sequence, and the final time interval (Last Duration) is preferably the nuclear magnetic resonance T2When the spectrum is attenuated to 0, the corresponding time value is 4-8 times, preferably 4 times; the number of data points is set between 2 and 200, preferably 2.
Generally, before using a time domain nuclear magnetic resonance apparatus, a standard oil sample is used to correct the instrument parameters such as the center frequency and the pulse width of the time domain nuclear magnetic resonance apparatus.
The signal intensity obtaining unit 20 is used for obtaining the nuclear magnetic resonance T of the sample to be measured2Recording the spectrum and the signal intensity at a specific time point as a first signal intensity; the sample to be tested is the same as the component type of the composite material with known component content, but the content is different.
The content calculation unit 30 is connected to the curve establishing unit 10 and the signal intensity obtaining unit 20, and the content calculation unit 30 is configured to calculate the component content of the sample to be tested according to the standard curve and the first signal intensity. And substituting the first signal intensity into the standard curve to calculate the composition content of the corresponding component type.
In this embodiment, the curve establishing unit is specifically configured to: obtaining NMR T of composite material with known content of n components2Signal intensity at a particular point in time in the spectrum; acquiring the content of a certain component of the composite material with known content of n components; and fitting to obtain a standard curve according to the signal intensity and the content of a certain component. The standard curve is: y is ax + b; wherein y is the content of the hydrogen atom-containing component in the composite material, and x is the signal intensity. In the specific implementation, the signals of the composite material with known content of n components are acquiredAnd (4) calculating the values of a and b according to the relevant data of the strength and the component content, and finally determining a standard curve.
The present invention also provides a computer-readable storage medium storing at least one program executable by a computer, the at least one program, when executed by the computer, causing the computer to perform the steps of the method provided by any of the embodiments of the present invention.
The invention is further illustrated with the aid of the following specific examples:
example 1
1. Experimental Material
A fused finger is 2.0(2.16kg), and has a density of 0.918g/cm3Linear Low Density Polyethylene (LLDPE) available from china petrochemical company. Analytically pure calcium carbonate particles, purchased from chemical reagents, Inc., of the national pharmaceutical group.
2. Laboratory apparatus
Table type TD-NMR spectrometer model mq20 from BRUKER BioSpin Corp (magnetic field strength 0.47T, probe diameter 10 mm). MS304S electronic balance, mettler-toledo, switzerland.
3 Experimental procedures
a) 7 composite materials of LLDPE and calcium carbonate with different component contents are prepared according to the mixture ratio of the following table 1, and the total mass of the composite material is about 300 mg. The composite was placed in a sample tube.
Table 1b) calibration of parameters such as center frequency, pulse width, magnet temperature, etc. of time domain nmr using the own standard sample of the instrument.
c) The 7 samples in table 1 above were placed in sequence in a time domain nmr.
d) Measurement of nuclear magnetic resonance T using solid-state echo (solidecho) sequence2Spectrum, parameters at test are set as: the sampling times are 16 times, the recycle delay is 2s, the gain value is 66db, the First Duration is 0.01ms, the Last Duration is 2.5ms, and the number of sampling points is 2.
e) The signal intensity at 0.025ms was recorded, and the signal intensity at 0.025ms was obtained for 7 samples, respectively, and the results are shown in table 2 below.
Table 2f) standard curves were fitted with LLDPE mass percent as the y-axis and signal intensity at 0.025ms as the x-axis: 1.2885x-0.4326 (R)20.9994), as shown in fig. 3.
g) Taking a composite material of calcium carbonate and LLDPE with unknown component content, adopting the same sequence and parameter setting, measuring the signal intensity at 0.025ms to be 53.82, substituting the signal intensity into the formula to obtain 68.91% of LLDPE by mass percent, and then the content of calcium carbonate is 31.09%.
Example 2
1 materials of the experiment
A fused finger is 5.0(2.16kg), and has a density of 0.935g/cm3Medium Density Polyethylene (MDPE) of (d), purchased from china petrochemical company. Analytically pure calcium carbonate particles, purchased from chemical reagents, Inc., of the national pharmaceutical group.
2 laboratory instruments
Table type TD-NMR spectrometer model mq20 from BRUKER BioSpin Corp (magnetic field strength 0.47T, probe diameter 10 mm). MS304S electronic balance, mettler-toledo, switzerland.
3 Experimental procedures
a) 7 composite materials of MDPE and calcium carbonate with different component contents are prepared according to the mixture ratio of the following table 3, and the total mass of the composite materials is about 300 mg. The composite was placed in a sample tube.
Table 3b) calibration of parameters such as center frequency, pulse width, magnet temperature, etc. of time domain nmr using the own standard sample of the instrument.
c) The 7 samples in table 3 above were placed in sequence in a time domain nmr.
d) Measurement of nuclear magnetic resonance T using solid-state echo (solidecho) sequence2Spectrum, parameters at test are set as: the sampling times are 16 times, the recycle delay is 2s, the gain value is 67db, the First Duration is 0.01ms, the Last Duration is 2.5ms, and the number of sampling points is 2.
e) The signal intensity at 0.025ms was recorded, and the signal intensity at 0.025ms was obtained for 7 samples, respectively, and the results are shown in table 4 below.
Table 4f) fitting to obtain a standard curve with MDPE mass percent as the y-axis and signal intensity at 0.025ms as the x-axis: y-1.2908 x-0.446 (R)20.9997) as shown in fig. 4.
g) Taking a composite material of calcium carbonate and MDPE with unknown component content, adopting the same sequence and parameter setting, measuring the signal intensity of 61.27 at 0.025ms, substituting the signal intensity into the formula to obtain 78.64% of MDPE by mass percent, and then the content of calcium carbonate is 21.36%.
Example 3
1. Experimental Material
A fused finger has a density of 7.34(2.16kg) and 0.956g/cm3High Density Polyethylene (HDPE) from china petrochemical company. Analytically pure calcium carbonate particles, purchased from chemical reagents, Inc., of the national pharmaceutical group.
2. Laboratory apparatus
Table type TD-NMR spectrometer model mq20 from BRUKER BioSpin Corp (magnetic field strength 0.47T, probe diameter 10 mm). MS304S electronic balance, mettler-toledo, switzerland.
3 Experimental procedures
a) 7 HDPE and calcium carbonate composites with different component contents were prepared according to the following formulation in Table 5, and the total mass of the composites was about 300 mg. The composite was placed in a sample tube.
TABLE 5
b) And correcting parameters such as the center frequency, the pulse width, the magnet temperature and the like of the time domain nuclear magnetic resonance instrument by using a standard sample carried by the instrument.
c) The 7 samples in table 5 above were placed in sequence in a time domain nmr.
d) Measurement of nuclear magnetic resonance T using solid-state echo (solidecho) sequence2Spectrum, parameters at test are set as: the sampling times are 16 times, the recycle delay is 2s, the gain value is 68db, the First Duration is 0.01ms, the Last Duration is 2.5ms, and the number of sampling points is 2.
e) The signal intensity at 0.025ms was recorded, and the signal intensity at 0.025ms was obtained for 7 samples, respectively, and the results are shown in table 6 below.
Table 6f) fitting to obtain a standard curve with HDPE mass percent as the y-axis and signal intensity at 0.025ms as the x-axis: 1.3384x-0.3129 (R)20.9983) as shown in fig. 5.
g) Taking a composite material of calcium carbonate and HDPE with unknown component content, adopting the same sequence and parameter setting, measuring the signal intensity at 0.025ms to be 43.92, substituting the signal intensity into the formula to obtain 58.47% of HDPE mass percent, and then the content of calcium carbonate is 41.53%.
Example 4
1. Experimental Material
A fused finger is 2.0(2.16kg), and has a density of 0.918g/cm3Is low in linearityDensity Polyethylene (LLDPE), available from china petrochemical company. Analytically pure sodium carbonate particles, purchased from chemical reagents, Inc., of the national pharmaceutical group.
2. Laboratory apparatus
Table type TD-NMR spectrometer model mq20 from BRUKER BioSpin Corp (magnetic field strength 0.47T, probe diameter 10 mm). MS304S electronic balance, mettler-toledo, switzerland.
3 Experimental procedures
a) 7 composite materials of LLDPE and sodium carbonate with different component contents are prepared according to the mixture ratio of the following table 7, and the total mass of the composite material is about 300 mg. The composite was placed in a sample tube.
Table 7b) calibration of parameters such as center frequency, pulse width, magnet temperature, etc. of time domain nmr using the own standard sample of the instrument.
c) The 7 samples in table 7 above were placed in sequence in a time domain nmr.
d) Measurement of nuclear magnetic resonance T using solid-state echo (solidecho) sequence2Spectrum, parameters at test are set as: the sampling times are 16 times, the recycle delay is 2s, the gain value is 66db, the First Duration is 0.01ms, the Last Duration is 2.5ms, and the number of sampling points is 2.
e) The signal intensity at 0.025ms was recorded, and the signal intensity at 0.025ms was obtained for 7 samples, respectively, and the results are shown in table 8 below.
Table 8f) standard curves were fitted with LLDPE mass percent as the y-axis and signal intensity at 0.025ms as the x-axis: y 1.287x +0.3573 (R)20.9996) as shown in fig. 6.
g) Taking a composite material of sodium carbonate and LLDPE with unknown component content, adopting the same sequence and parameter setting, measuring that the signal intensity at 0.025ms is 48.61, substituting the signal intensity into the above formula to obtain that the mass percent of LLDPE is 62.92%, and the content of sodium carbonate is 37.08%.
The above example can prove that the component content in the composite material composed of the substance without hydrogen atoms and the substance containing hydrogen atoms can be rapidly and quantitatively determined by using the nuclear magnetic resonance method, and the method is particularly suitable for determining the content of the inorganic filler in the high molecular polymer.
While the preferred embodiments of the present invention have been illustrated in the accompanying drawings, those skilled in the art will appreciate that various modifications can be made to the present invention without departing from the scope and spirit of the invention. For instance, features illustrated or described as part of one embodiment, can be used with another embodiment to yield a still further embodiment. The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the scope of the present invention, which is defined in the appended claims.
Claims (10)
1. A composite material component content determination method based on time domain nuclear magnetic resonance is characterized by comprising the following steps:
s1 obtaining nuclear magnetic resonance T of the composite material with known content of n components2Establishing a standard curve of signal intensity and component content at a specific time point according to the spectrum;
s2, obtaining nuclear magnetic resonance T of the sample to be detected2Recording the spectrum and the signal intensity at the specific time point as a first signal intensity;
and S3, calculating the component content of the sample to be detected according to the standard curve and the first signal intensity.
2. The method for determining the component content of the composite material based on the time-domain nuclear magnetic resonance according to claim 1, wherein the establishing of the standard curve of the signal intensity and the component content at a specific time point specifically comprises:
obtaining NMR T of composite material with known content of n components2Signal intensity at a particular point in time in the spectrum;
acquiring the content of a certain component of the composite material with known content of n components;
and fitting to obtain a standard curve according to the signal intensity and the content of a certain component.
3. The method for determining the component content of the composite material based on the time-domain nuclear magnetic resonance according to claim 2, wherein the standard curve is as follows: y is ax + b; wherein y is the content of the hydrogen atom-containing component in the composite material, and x is the signal intensity.
4. The method for determining the content of the component of the composite material based on the time-domain nuclear magnetic resonance according to claim 1, wherein n is any natural number from 2 to 50.
5. The method for determining component content of composite material based on time-domain nuclear magnetic resonance according to claim 1, wherein the step S1 includes using a solid echo sequence to measure the composite material with n known component contents on a time-domain nuclear magnetic resonance apparatus to obtain the corresponding T-nmr2A spectrum; wherein:
the parameter settings of the solid echo sequence comprise at least one of: the scanning times are set to be between 4 and 128 times; the cyclic waiting time is set to be 0.5-50 seconds; the gain value is set to be determined according to an actual sample according to the principle that data do not overflow during testing; the first time interval (FirstDuration) is the shortest time value defined by the solid echo sequence, and the final time interval (LastDuration) is the nuclear magnetic resonance T2When the spectrum is attenuated to 0, the corresponding time value is 4-8 times; the number of data points is set between 2 and 200.
6. A composite material component content determination system based on time domain nuclear magnetic resonance is characterized by comprising:
a curve establishing unit for obtaining the content of n componentsNuclear magnetic resonance T of known composite materials2Establishing a standard curve of signal intensity and component content at a specific time point according to the spectrum;
a signal intensity acquisition unit for acquiring nuclear magnetic resonance T of the sample to be measured2Recording the spectrum and the signal intensity at the specific time point as a first signal intensity;
and the content calculation unit is used for calculating the component content of the sample to be detected according to the standard curve and the first signal intensity.
7. The time-domain nuclear magnetic resonance-based composite material component content determination system according to claim 6, wherein the curve creation unit is specifically configured to:
obtaining NMR T of composite material with known content of n components2Signal intensity at a particular point in time in the spectrum;
acquiring the content of a certain component of the composite material with known content of n components;
and fitting to obtain a standard curve according to the signal intensity and the content of a certain component.
8. The time-domain nuclear magnetic resonance-based composite material component content determination system according to claim 7, wherein the standard curve is: y is ax + b; wherein y is the content of the hydrogen atom-containing component in the composite material, and x is the signal intensity.
9. The time-domain nuclear magnetic resonance-based composite material component content determination system according to claim 1, wherein n is any natural number from 2 to 50, and n is preferably 7.
10. A computer-readable storage medium storing at least one program executable by a computer, the at least one program, when executed by the computer, causing the computer to perform the steps of the method of any one of claims 1 to 5.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910966273.4A CN112649459A (en) | 2019-10-12 | 2019-10-12 | Time-domain nuclear magnetic resonance-based composite material component content determination method and system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910966273.4A CN112649459A (en) | 2019-10-12 | 2019-10-12 | Time-domain nuclear magnetic resonance-based composite material component content determination method and system |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN112649459A true CN112649459A (en) | 2021-04-13 |
Family
ID=75343575
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910966273.4A Pending CN112649459A (en) | 2019-10-12 | 2019-10-12 | Time-domain nuclear magnetic resonance-based composite material component content determination method and system |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112649459A (en) |
Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20050270026A1 (en) * | 2004-05-05 | 2005-12-08 | Bruker Biospin Gmbh | Method for determining the content of at least one component of a sample by means of a nuclear magnetic resonance pulse spectrometer |
| US20090033325A1 (en) * | 2004-07-29 | 2009-02-05 | Iwao Miura | Nuclear Magnetic Resonance Measuring Method for Solid Samples |
| CN102007236A (en) * | 2008-04-16 | 2011-04-06 | 日信工业株式会社 | Carbon nanofiber, method for production thereof, method for production of carbon fiber composite material using carbon nanofiber, and carbon fiber composite material |
| CN103563056A (en) * | 2011-04-15 | 2014-02-05 | 富士纺控股株式会社 | Polishing pad and manufacturing method therefor |
| CN106468670A (en) * | 2016-09-29 | 2017-03-01 | 河北中烟工业有限责任公司 | A kind of tobacco moisture percentage method of testing based on time domain nuclear magnetic resonance, NMR inverting peak area |
| CN107655922A (en) * | 2017-09-05 | 2018-02-02 | 中国石油天然气股份有限公司 | Nuclear magnetic resonance-based nondestructive testing method for water content of hydrocarbon source rock |
| CN108350249A (en) * | 2015-10-29 | 2018-07-31 | 株式会社电装 | Fuel impeller of pump |
| CN109613042A (en) * | 2018-12-27 | 2019-04-12 | 中国林业科学研究院木材工业研究所 | A kind of pine class sawn timber Oleoresin Contents test method based on time domain nuclear magnetic resonance |
-
2019
- 2019-10-12 CN CN201910966273.4A patent/CN112649459A/en active Pending
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20050270026A1 (en) * | 2004-05-05 | 2005-12-08 | Bruker Biospin Gmbh | Method for determining the content of at least one component of a sample by means of a nuclear magnetic resonance pulse spectrometer |
| US20090033325A1 (en) * | 2004-07-29 | 2009-02-05 | Iwao Miura | Nuclear Magnetic Resonance Measuring Method for Solid Samples |
| CN102007236A (en) * | 2008-04-16 | 2011-04-06 | 日信工业株式会社 | Carbon nanofiber, method for production thereof, method for production of carbon fiber composite material using carbon nanofiber, and carbon fiber composite material |
| CN103563056A (en) * | 2011-04-15 | 2014-02-05 | 富士纺控股株式会社 | Polishing pad and manufacturing method therefor |
| CN108350249A (en) * | 2015-10-29 | 2018-07-31 | 株式会社电装 | Fuel impeller of pump |
| CN106468670A (en) * | 2016-09-29 | 2017-03-01 | 河北中烟工业有限责任公司 | A kind of tobacco moisture percentage method of testing based on time domain nuclear magnetic resonance, NMR inverting peak area |
| CN107655922A (en) * | 2017-09-05 | 2018-02-02 | 中国石油天然气股份有限公司 | Nuclear magnetic resonance-based nondestructive testing method for water content of hydrocarbon source rock |
| CN109613042A (en) * | 2018-12-27 | 2019-04-12 | 中国林业科学研究院木材工业研究所 | A kind of pine class sawn timber Oleoresin Contents test method based on time domain nuclear magnetic resonance |
Non-Patent Citations (4)
| Title |
|---|
| KATHRYN E. WASHBURN ET AL.: "Updated methodology for nuclear magnetic resonance characterization of shales", JOURNAL OF MAGNETIC RESONANCE, vol. 233, 4 May 2013 (2013-05-04), pages 17 - 28, XP028674913, DOI: 10.1016/j.jmr.2013.04.014 * |
| 李超;张明辉;于建芳;: "利用核磁共振自由感应衰减曲线测定木材含水率", 北京林业大学学报, no. 04, pages 142 - 145 * |
| 李鲠颖等: "固态NMR中自旋Ⅰ=1体系的魔术回波序列", 波谱学杂志, vol. 5, no. 4, pages 341 - 348 * |
| 邓风等: "用23Na和27Al固体核磁共振研究Na+在γ/-Al2O3上的吸附状态", 物理化学学报, vol. 10, no. 1, pages 1 - 5 * |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US4701705A (en) | NMR moisture measurements | |
| CN103018148B (en) | Method for measuring porosity of coal core | |
| CN104075974A (en) | Method for accurately measuring shale porosity by adopting low-field nuclear magnetic resonance | |
| CN107655922B (en) | Nuclear magnetic resonance-based nondestructive testing method for water content of hydrocarbon source rock | |
| JP2014528070A (en) | Detection of hazardous substances in containers using measurements based on nuclear magnetic resonance | |
| CN106442599B (en) | Method and device for measuring oil content of rock | |
| CN107782705B (en) | Method and device for measuring oil content of rock | |
| Rigger et al. | Certified reference material for use in 1H, 31P, and 19F quantitative NMR, ensuring traceability to the International System of Units | |
| CN103411953B (en) | A kind of method of farm chemical emulsion preparation being carried out to field quick detection | |
| US6596153B1 (en) | Method for analyzing a gas sample | |
| CN110879234B (en) | Method for rapidly detecting total moisture of coal based on low-field nuclear magnetic resonance | |
| CN112649459A (en) | Time-domain nuclear magnetic resonance-based composite material component content determination method and system | |
| JP2012220499A (en) | Method and apparatus for automated raw material screening | |
| WO2023197691A1 (en) | Method for obtaining absolute spin number of unpaired electrons of sample | |
| CN105334238A (en) | Method for determining rare earth gadolinium ion concentration in solution | |
| Inagaki et al. | Certification of water content in NMIJ CRM 4222-a, water standard solution 0.1 mg g− 1, by coulometric and volumetric Karl Fischer titration | |
| CN103674994A (en) | Gelatin standard database construction method and system, and gelatin identification method and system | |
| JP2005345193A (en) | Quantitative determination method using nuclear magnetic resonance method and/or diffusion factor measurement method based on nuclear magnetic resonance | |
| CN105547896A (en) | Test method of crosslinking density of rubber foaming material | |
| CN105784750A (en) | Method of utilizing low-field nuclear magnetism to detect oil content of Euphausia superba microcapsules | |
| Prado et al. | Rapid method to screen unopened bottles to detect concealed drugs | |
| US3039048A (en) | Gyromagnetic resonance detection method and apparatus | |
| Melnick et al. | Determination of apparent spin-spin relaxation time T2★ using a super-regenerative spectrometer | |
| CN108508056A (en) | A kind of method of accurate quantification trace solid free-radical contents | |
| CN106970103A (en) | The detection method of impurity in lithium hexafluoro phosphate |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |