Preparation and valuing method of 1, 1, 2, 2-tetrachloroethane deuterated solution standard substance

Abstract

The invention provides a preparation and valuing method of a 1, 1, 2, 2-tetrachloroethane deuterated solution standard substance, and the preparation method of the 1, 1, 2, 2-tetrachloroethane deuterated solution standard substance comprises the following steps: 1, selecting a mother solution and a deuterated reagent; and 2, preparing the 1, 1, 2, 2-tetrachloroethane deuterated solution standard substance. The invention relates to a preparation method of a 1, 1, 2, 2-tetrachloroethane deuterated solution standard substance, and a valuing method of the 1, 1, 2, 2-tetrachloroethane deuterated solution standard substance prepared by the preparation method of the 1, 1, 2, 2-tetrachloroethane deuterated solution standard substance specifically comprises the following steps: step 1, sub-packaging and packaging; step 2, carrying out uniformity inspection; step 3, stability inspection; and step 4, uncertainty evaluation. The 1, 1, 2, 2-tetrachloroethane deuterated solution standard substance for superconducting nuclear magnetic resonance quantification, provided by the invention, is a solution standard substance in which the content of 1, 1, 2, 2-tetrachloroethane ranges from 0.05% to 0.5%. The 1, 1, 2, 2-tetrachloroethane deuterated solution standard substance is used, so that the test steps of superconducting nuclear magnetic resonance quantification can be reduced, and the measurement uncertainty is reduced.

Description

Technical Field

[0001] This invention belongs to the field of materials preparation technology, and relates to 1,1,2,2-tetrachloroethane deuterated solution, specifically to a method for preparing and determining the value of a 1,1,2,2-tetrachloroethane deuterated solution standard. Background Technology

[0002] Chromatography is commonly used to determine trace components in organic compounds, but it can sometimes be limited, such as the lack of standards for signal correction, poor separation between trace components and the bulk, and the absence of a response signal from the trace component in the detector. Superconducting nuclear magnetic resonance (NMR) quantitative analysis, as an increasingly mature instrumental analytical method, complements chromatography in the determination of trace components in organic compounds, achieving a mutually beneficial relationship.

[0003] Superconducting nuclear magnetic resonance (NMR) quantitative analyte technology does not require a reference standard. It only needs an internal standard signal that does not overlap with the characteristic absorption peaks of each component in the organic compound, and the concentration of this internal standard in the sample is known. The content of trace components can then be calculated using the superconducting NMR quantitative equation. Commonly used internal standards are mostly purity standards or analytically pure compounds with known concentrations.

[0004] Trace components in organic compounds typically contain between 0.01% and 1%. To ensure accurate measurement, the peak areas of the internal standard signal and the trace component signal should not differ too much. This requires the internal standard to be diluted at least once before being added to the sample to be tested, which increases the measurement uncertainty and adds to the measurement steps. Summary of the Invention

[0005] In view of the shortcomings of the existing technology, the purpose of this invention is to provide a method for preparing and determining the value of a 1,1,2,2-tetrachloroethane deuterated solution standard, so as to solve the technical problems of low detection efficiency and high measurement uncertainty of trace components in the existing technology.

[0006] To solve the above-mentioned technical problems, the present invention adopts the following technical solution: A method for preparing a standard reference of 1,1,2,2-tetrachloroethane deuterated solution, the method specifically including the following steps: Step 1: Select 1,1,2,2-tetrachloroethane with a purity ≥99.5% as the mother liquor, and select deuterated reagents with a purity ≥99.5% and a deuteration degree ≥99.5%. Step 2: Accurately weigh 1,1,2,2-tetrachloroethane from Step 1 into a container using a balance with an accuracy of 1 / 100,000. Then add the deuterated reagent from Step 1 into the container, seal the container, and sonicate to mix the 1,1,2,2-tetrachloroethane and the deuterated reagent evenly to obtain a standard 1,1,2,2-tetrachloroethane deuterated solution. Let it stand under nitrogen protection.

[0007] This invention also has the following technical features: Specifically, in step one, weigh 100g of the deuterated reagent from step one.

[0008] Specifically, in step two, add 50mg to 500mg of the mother liquor from step one.

[0009] Specifically, the container is a brown, capped liquid storage bottle.

[0010] This invention also protects a method for determining the value of the 1,1,2,2-tetrachloroethane deuterated solution standard prepared by the method described above, the method specifically including the following steps: Step 1, Disassembly and Packaging: Under nitrogen protection, the prepared 1,1,2,2-tetrachloroethane deuterated solution standard was dispensed into multiple 1 mL brown ampoules, 0.5 mL per ampoule, 5 ampoules per batch, and immediately sealed with a sealer over a low flame. Step 2, Uniformity check: According to the time sequence, 5 bottles of samples were randomly selected from each of the initial batch, intermediate batch and final batch stages of the dispensing in step one, for a total of 15 bottles of samples. Each bottle of sample was measured three times. The F test was used to perform statistical calculations to determine whether the 1,1,2,2-tetrachloroethane deuterated solution standard material after packaging was homogeneous, and the 1,1,2,2-tetrachloroethane deuterated solution standard material after passing the homogeneity test was obtained. Step 3, stability test: After passing the homogeneity test in step two, the 1,1,2,2-tetrachloroethane deuterated solution standard was stored at room temperature in the dark for an extended period. Three samples were randomly selected at different time points, and each sample was measured twice. The content of 1,1,2,2-tetrachloroethane in the 1,1,2,2-tetrachloroethane deuterated solution standard was determined by gas chromatography with external standard method. The t-test was used to test the significance of the change trend of the content of 1,1,2,2-tetrachloroethane in the 1,1,2,2-tetrachloroethane deuterated solution standard over time, and to determine whether the prepared 1,1,2,2-tetrachloroethane deuterated solution standard was stable. The 1,1,2,2-tetrachloroethane deuterated solution standard that passed the stability test was obtained. Step 4, Uncertainty Evaluation: Step 4.1, Uncertainty introduced by the gravimetric method: Uncertainty of gravimetric measurement results According to Type B uncertainty analysis, the Type B uncertainty mainly comes from the uncertainty caused by the balance tolerance. The tolerance of a balance with an accuracy of 1 / 100,000 is 0.01 mg. According to uniformity analysis, the Type B uncertainty is... g, then ; In the formula: The mass of the mother liquor is expressed in grams. The mass of the deuterated reagent is expressed in grams. Step 4.2, according to the formula Calculate the uncertainty introduced by the 1,1,2,2-tetrachloroethane deuterated solution standard material after passing the homogeneity test in step two; In the formula: Uncertainty introduced for homogeneity; P represents the mass percentage of 1,1,2,2-tetrachloroethane in the deuterated 1,1,2,2-tetrachloroethane standard solution, expressed as %. ; This represents the uncertainty component caused by inhomogeneity between bottles. ; The variance of measurement repeatability in the assessment of bottle homogeneity; for degrees of freedom; The number of times each sample is tested; Step 4.3, according to the formula Calculate the uncertainty introduced by the 1,1,2,2-tetrachloroethane deuterated solution standard material after passing the stability test in step three; In the formula: Uncertainty introduced for stability; for The standard deviation; For the given retention period; Step 4.4, according to the formula Calculate the relative standard uncertainty of the 1,1,2,2-tetrachloroethane content in the 1,1,2,2-tetrachloroethane deuterated solution standard; In the formula: This refers to the relative standard uncertainty. Step 4.5, according to the formula Calculate the relative expanded uncertainty of the 1,1,2,2-tetrachloroethane content in the standard reference of 1,1,2,2-tetrachloroethane deuterated solution; In the formula: This refers to the relative expanded uncertainty; For expansion factor, =2, confidence probability 95%.

[0011] Specifically, the nitrogen gas is high-purity nitrogen gas with a purity of ≥99.999%.

[0012] Specifically, the nitrogen flow rate in step four is 10 psi.

[0013] Compared with the prior art, the present invention has the following technical effects: (I) The 1,1,2,2-tetrachloroethane deuterated solution standard material for quantitative superconducting nuclear magnetic resonance proposed in this invention is a solution standard material with a 1,1,2,2-tetrachloroethane content ranging from 0.05% to 0.5%. Using the 1,1,2,2-tetrachloroethane deuterated solution standard material can reduce the testing steps for quantitative superconducting nuclear magnetic resonance and lower the measurement uncertainty.

[0014] (II) The 1,1,2,2-tetrachloroethane deuterated solution standard material for superconducting nuclear magnetic resonance quantification proposed in this invention has good homogeneity and stability, and is mainly used for superconducting nuclear magnetic resonance determination of trace components in organic compounds. Attached Figure Description

[0015] Figure 1 The quantitative superconducting nuclear magnetic resonance hydrogen spectrum of acetonitrile, the residual solvent in the HMX standard material. Detailed Implementation

[0016] It should be noted that, unless otherwise specified, the equipment and materials used in this invention are all those known in the prior art.

[0017] Following the above technical solutions, specific embodiments of the present invention are given below. It should be noted that the present invention is not limited to the following specific embodiments, and all equivalent modifications made based on the technical solutions of this application fall within the protection scope of the present invention.

[0018] Example 1: This embodiment provides a method for preparing a standard reference of 1,1,2,2-tetrachloroethane deuterated solution. In this embodiment, the mother liquor is 1,1,2,2-tetrachloroethane, and the deuteration reagent is deuterated dimethyl sulfoxide.

[0019] The method specifically includes the following steps: Step 1: Select 1,1,2,2-tetrachloroethane with a purity ≥99.5% as the mother liquor, and select deuterated dimethyl sulfoxide with a purity ≥99.8% and a deuteration degree ≥99.8%. Step 2: Using a balance with an accuracy of 1 / 100,000, accurately weigh 0.11264 g of 1,1,2,2-tetrachloroethane from Step 1 into a brown capped storage bottle of known weight. Then, add 103.32568 g of deuterated dimethyl sulfoxide from Step 1 to the brown capped storage bottle. After sealing the brown capped storage bottle, place it in an ultrasonic oscillator and ultrasonically oscillate for 5 minutes to mix the 1,1,2,2-tetrachloroethane and deuterated dimethyl sulfoxide evenly, obtaining a 1,1,2,2-tetrachloroethane deuterated dimethyl sulfoxide solution standard substance, and let it stand under nitrogen protection.

[0020] In this invention, deuterated dimethyl sulfoxide possesses characteristics of high polarity, high boiling point, low viscosity, good thermal stability, and good solubility. The proton NMR signal of its residual protons is... δ H Between 2.50 and 2.55, there is a quintet peak. It does not overlap with the signals of alkyl compounds, olefin compounds, and phenyl compounds, and it does not readily react or associate with these compounds. It is a widely used deuterated reagent.

[0021] In this embodiment, the method for determining the value of the 1,1,2,2-tetrachloroethane deuterated dimethyl sulfoxide solution standard prepared by the method described above specifically includes the following steps: Step 1, Disassembly and Packaging: Under nitrogen protection, the prepared 1,1,2,2-tetrachloroethane deuterated solution standard was dispensed into 180 1 mL brown ampoules, 0.5 mL per ampoule, 5 ampoules per batch, and immediately sealed with a sealer over a low flame. In this embodiment, the nitrogen gas is high-purity nitrogen with a purity greater than 99.999%, and the flow rate of the nitrogen gas is 10 psi.

[0022] Step 2, Uniformity check: Following the chronological order, 5 bottles of samples were randomly selected from each of the initial, intermediate, and final batches of the packaging process in step one, for a total of 15 bottles. The content of 1,1,2,2-tetrachloroethane in the 1,1,2,2-tetrachloroethane deuterated dimethyl sulfoxide solution standard material was determined by gas chromatography with external standard method. The determination was repeated three times, and statistical calculations were performed using the F-test to determine whether the packaged 1,1,2,2-tetrachloroethane deuterated dimethyl sulfoxide solution standard material was homogeneous. The homogeneity test was then passed to obtain the 1,1,2,2-tetrachloroethane deuterated solution standard material. In this embodiment, the systematic error between the group measurements is determined by comparing the between-group variance and the within-group variance. If the ratio of the two is less than the critical value of the statistical test, the sample is considered to be homogeneous.

[0023] In this embodiment, the between-group variance is the variance among the five bottles of samples in the same batch, and the within-group variance is the variance between the initial batch, the intermediate batch, or the final batch.

[0024] In this embodiment, according to the formula To determine the variance between groups, use the formula... To determine the within-group variance, the formula is: The variance between groups; Within-group variance; The sum of squares between groups; The sum of squares within the group; Degrees of freedom between groups; Within-group degrees of freedom; Then the statistic According to the degrees of freedom between groups and intragroup freedom Given a significance level α (α=0.05), the critical value can be found from the F-table. F α The value is used to determine the homogeneity of the sample. If calculated according to the formula... value, < F α If there is no significant difference within or between groups, the sample is considered homogeneous. The homogeneity test results of the 1,1,2,2-tetrachloroethane deuterated dimethyl sulfoxide solution standard prepared in this example are shown in Table 1.

[0025] Table 1. Homogeneity test results of 1,1,2,2-tetrachloroethane deuterated dimethyl sulfoxide solution standard material

[0026] As can be seen from Table 2, there is no significant difference between the average value and the standard deviation of the measurements taken inside and between bottles, and the precision of the measurements is within the range of the set value accuracy, which proves that the 1,1,2,2-tetrachloroethane deuterated dimethyl sulfoxide solution standard material prepared in this embodiment has good homogeneity.

[0027] Step 3, stability test: After passing the homogeneity test in step two, the 1,1,2,2-tetrachloroethane deuterated dimethyl sulfoxide solution standard was stored at room temperature in the dark for an extended period. Three samples were randomly selected at intervals of 1 month, 3 months, 5 months, 8 months, 12 months, 18 months, and 24 months, with each sample measured twice. The content of 1,1,2,2-tetrachloroethane in the 1,1,2,2-tetrachloroethane deuterated dimethyl sulfoxide solution standard was determined using gas chromatography with external standard method. The significance of the change in the content of 1,1,2,2-tetrachloroethane deuterated dimethyl sulfoxide solution standard over time was tested using the t-test to determine the stability of the prepared 1,1,2,2-tetrachloroethane deuterated dimethyl sulfoxide solution standard. The 1,1,2,2-tetrachloroethane deuterated dimethyl sulfoxide solution standard was obtained after passing the stability test. In this embodiment, the gas chromatography analysis conditions are as follows: capillary column: 30m × 0.250mm × 0.25um; injection port: 200℃; detector: FID, 200℃; carrier gas: nitrogen, purity 99.999%; injection flow rate: 2mL / min, constant flow; injection volume: 0.1uL; split ratio: 10:1; considering that the boiling point of 1,1,2,2-tetrachloroethane is 146.5℃ and the boiling point of the deuterated reagent is 189℃, the column temperature is selected as 120℃ isothermal mode; separation time: 3min.

[0028] In this embodiment, the 1,1,2,2-tetrachloroethane deuterated dimethyl sulfoxide solution standard was prepared into a standard solution with a concentration of 0.5 mg / mL to 5.0 mg / mL using gas chromatography with external standard method. Then, the signal intensity of 1,1,2,2-tetrachloroethane in the standard solution and the test sample was measured sequentially according to the formula... Calculate the content of 1,1,2,2-tetrachloroethane in the sample to be tested; In the formula: The content of 1,1,2,2-tetrachloroethane in the standard solution is expressed as a mass fraction (%). The signal intensity of 1,1,2,2-tetrachloroethane in the sample to be tested; The signal intensity of 1,1,2,2-tetrachloroethane in the standard solution; The concentration of the standard solution is expressed in mg / mL. The volume of the sample to be tested is expressed in mL. The mass of the sample to be tested is expressed in mg.

[0029] In this embodiment, the t-test was used to examine the significance of the trend of 1,1,2,2-tetrachloroethane content over time in the 1,1,2,2-tetrachloroethane deuterated dimethyl sulfoxide solution standard (trend analysis method). The 1,1,2,2-tetrachloroethane content measured during the stability study was plotted against storage time to obtain a graph showing the relationship between the 1,1,2,2-tetrachloroethane content and time, and a linear equation was fitted. ; In the formula: The slope term represents the rate at which the purity of the standard substance changes with time (X); This is the intercept term, representing the starting point of the stability assessment; Storage time, in months; The characteristic values ​​are for the standard reference material of 1,1,2,2-tetrachloroethane deuterated dimethyl sulfoxide solution; The estimated value is calculated using the formula Calculated; In the formula: This refers to the i-th time point; This refers to the observation value at the i-th time point; This is the average value across all time points; The average of all observations; The estimated value is calculated using the formula Calculated; standard deviation According to the formula Calculated; In the formula: s is the standard deviation of each point on the straight line, according to the formula Calculated; where The number of measurements.

[0030] Based on the standard deviation of β1, the t-test is used to make the following judgment: If <t 0.95 , n-2 • When the slope is not significant, it indicates that no instability of the characteristic value has been observed. >t 0.95 , n-2 • When the slope was significant, the data was recalculated after shortening the stable storage time to obtain the stability time of the standard substance. The stability test results of the 1,1,2,2-tetrachloroethane deuterated dimethyl sulfoxide solution standard substance are shown in Table 2.

[0031] Table 2. Stability test results of 1,1,2,2-tetrachloroethane deuterated dimethyl sulfoxide solution standard material

[0032] Step 4, Uncertainty Evaluation: Uncertainty μ of gravimetric measurement results r (m) According to Type B uncertainty analysis, the Type B uncertainty mainly comes from the uncertainty caused by the balance tolerance. The tolerance of a balance with an accuracy of 1 / 100,000 is 0.01 mg. According to uniformity analysis, the Type B uncertainty is... g, then ; In the formula: The mass of the mother liquor is expressed in grams. The mass of the deuterated reagent is expressed in grams. According to the formula Calculate the uncertainty introduced by the 1,1,2,2-tetrachloroethane deuterated solution standard material after passing the homogeneity test in step two; In the formula: Uncertainty introduced for homogeneity; P represents the mass percentage of 1,1,2,2-tetrachloroethane in the deuterated 1,1,2,2-tetrachloroethane standard solution, expressed as %. ; This represents the uncertainty component caused by inhomogeneity between bottles. ; The variance of measurement repeatability in the assessment of bottle homogeneity; for degrees of freedom; The number of times each sample is tested; Step 4.3, according to the formula Calculate the uncertainty introduced by the 1,1,2,2-tetrachloroethane deuterated solution standard material after passing the stability test in step three; In the formula: Uncertainty introduced for stability; for The standard deviation; For the given retention period; Step 4.4, according to the formula Calculate the relative standard uncertainty of the 1,1,2,2-tetrachloroethane content in the 1,1,2,2-tetrachloroethane deuterated solution standard; In the formula: This refers to the relative standard uncertainty. Step 4.5, according to the formula Calculate the relative expanded uncertainty of the 1,1,2,2-tetrachloroethane content in the standard reference of 1,1,2,2-tetrachloroethane deuterated solution; In the formula: This refers to the relative expanded uncertainty; For expansion factor, =2, confidence probability 95%.

[0033] In this embodiment, the uncertainty of the 1,1,2,2-tetrachloroethane deuterated dimethyl sulfoxide solution standard is shown in Table 3.

[0034] Table 3 Uncertainty of 1,1,2,2-Tetrachloroethane Deuterated Dimethyl Sulfoxide Solution Standard Material

[0035] Step 4.6, Superconducting NMR quantitative analysis of residual solvent content in HMX standard material: Qualitative analysis: Qualitative analysis using superconducting nuclear magnetic resonance (NMR) revealed that the residual solvent in the HMX standard material is acetonitrile. Figure 1 It can be seen that δH 2.06 The peak represents the characteristic signal of the residual solvent acetonitrile.

[0036] Method Principle: A certain mass of HMX standard sample is weighed and dissolved in a superconducting nuclear magnetic resonance quantitative 1,1,2,2-tetrachloroethane deuterated dimethyl sulfoxide solution standard. The content of the residual solvent is obtained by utilizing the functional relationship between the ratio of the NMR signal of 1,1,2,2-tetrachloroethane to the residual solvent and its content and chemical structure. The quantitative function is as follows:

[0037] In the formula: The content of the 1,1,2,2-tetrachloroethane deuterated dimethyl sulfoxide solution standard substance is expressed in g / g. The percentage content of the analyte in the sample is expressed as %. The mass of the added 1,1,2,2-tetrachloroethane deuterated dimethyl sulfoxide standard solution is expressed in mg. The mass of the sample is expressed in mg. The relative molecular mass of 1,1,2,2-tetrachloroethane is 167.86. The relative molecular mass of the analyte is given. The number of resonance nuclei on the functional groups that represent the characteristic signal of 1 mole of 1,1,2,2-tetrachloroethane; The number of resonance nuclei on the functional group that generate a signal for 1 mole of the analyte is 2; The peak area of ​​the characteristic signal peak of 1,1,2,2-tetrachloroethane; The peak area of ​​the characteristic quantitative peak of the analyte; Calculations show that the residual solvent acetonitrile content is 0.00625%, and the relative standard deviation (RSD) of the six parallel samples is 0.76%.

Claims

1. A method for preparing a standard reference of 1,1,2,2-tetrachloroethane deuterated solution, characterized in that, The method specifically includes the following steps: Step 1: Select 1,1,2,2-tetrachloroethane with a purity ≥99.5% as the mother liquor, and select deuterated reagents with a purity ≥99.5% and a deuteration degree ≥99.5%. Step 2: Accurately weigh 1,1,2,2-tetrachloroethane from Step 1 into a container using a balance with an accuracy of 1 / 100,000. Then add the deuterated reagent from Step 1 into the container, seal the container, and sonicate to mix the 1,1,2,2-tetrachloroethane and the deuterated reagent evenly to obtain a standard 1,1,2,2-tetrachloroethane deuterated solution. Let it stand under nitrogen protection.

2. The method for preparing the 1,1,2,2-tetrachloroethane deuterated solution standard as described in claim 1, characterized in that, In step one, weigh 100g of the deuterated reagent from step one.

3. The method for preparing the 1,1,2,2-tetrachloroethane deuterated solution standard as described in claim 1, characterized in that, In step two, add 50mg to 500mg of the mother liquor from step one.

4. The method for preparing the 1,1,2,2-tetrachloroethane deuterated solution standard as described in claim 1, characterized in that, The container is a brown, capped liquid storage bottle.

5. A method for determining the value of a standard reference material of 1,1,2,2-tetrachloroethane deuterated solution, characterized in that, The 1,1,2,2-tetrachloroethane deuterated solution standard is prepared by the method described in any one of claims 1 to 4. The method specifically includes the following steps: Step 1, Disassembly and Packaging: Under nitrogen protection, the prepared 1,1,2,2-tetrachloroethane deuterated solution standard was dispensed into multiple 1 mL brown ampoules, 0.5 mL per ampoule, 5 ampoules per batch, and immediately sealed with a sealer over a low flame. Step 2, Uniformity check: Following the chronological order, 5 bottles of samples were randomly selected from each of the initial, intermediate, and final batches of the packaging process in step one, for a total of 15 bottles. The content of 1,1,2,2-tetrachloroethane in the 1,1,2,2-tetrachloroethane deuterated solution standard material was determined by gas chromatography with external standard method. The determination was repeated three times, and statistical calculations were performed using the F-test to determine whether the packaged 1,1,2,2-tetrachloroethane deuterated solution standard material was homogeneous. The homogeneity test was then passed to obtain the 1,1,2,2-tetrachloroethane deuterated solution standard material. Step 3, stability test: After passing the homogeneity test in step two, the 1,1,2,2-tetrachloroethane deuterated solution standard was stored at room temperature in the dark for an extended period. Three samples were randomly selected at different time points, and each sample was measured twice. The content of 1,1,2,2-tetrachloroethane in the 1,1,2,2-tetrachloroethane deuterated solution standard was determined by gas chromatography with external standard method. The t-test was used to test the significance of the change trend of the content of 1,1,2,2-tetrachloroethane in the 1,1,2,2-tetrachloroethane deuterated solution standard over time, and to determine whether the prepared 1,1,2,2-tetrachloroethane deuterated solution standard was stable. The 1,1,2,2-tetrachloroethane deuterated solution standard that passed the stability test was obtained. Step 4, Uncertainty Evaluation: Step 4.1, Uncertainty introduced by the gravimetric method: Uncertainty of gravimetric measurement results According to Type B uncertainty analysis, the Type B uncertainty mainly comes from the uncertainty caused by the balance tolerance. The tolerance of a balance with an accuracy of 1 / 100,000 is 0.01 mg. According to uniformity analysis, the Type B uncertainty is... g, then ; In the formula: The mass of the mother liquor is expressed in grams. The mass of the deuterated reagent is expressed in grams. Step 4.2, according to the formula Calculate the uncertainty introduced by the 1,1,2,2-tetrachloroethane deuterated solution standard material after passing the homogeneity test in step two; In the formula: Uncertainty introduced for homogeneity; This represents the mass percentage of 1,1,2,2-tetrachloroethane in the standard 1,1,2,2-tetrachloroethane deuterated solution, expressed as %. ; This represents the uncertainty component caused by inhomogeneity between bottles. ; The variance of measurement repeatability in the assessment of bottle homogeneity; for degrees of freedom; The number of times each sample is tested; Step 4.3, according to the formula Calculate the uncertainty introduced by the 1,1,2,2-tetrachloroethane deuterated solution standard material after passing the stability test in step three; In the formula: Uncertainty introduced for stability; for The standard deviation; For the given retention period; Step 4.4, according to the formula Calculate the relative standard uncertainty of the 1,1,2,2-tetrachloroethane content in the 1,1,2,2-tetrachloroethane deuterated solution standard; In the formula: This refers to the relative standard uncertainty. Step 4.5, according to the formula Calculate the relative expanded uncertainty of the 1,1,2,2-tetrachloroethane content in the standard reference of 1,1,2,2-tetrachloroethane deuterated solution; In the formula: This refers to the relative expanded uncertainty; For expansion factor, =2, confidence probability 95%.

6. The method for determining the value of the 1,1,2,2-tetrachloroethane deuterated solution standard material as described in claim 5, characterized in that, The nitrogen gas is high-purity nitrogen with a purity of ≥99.999%.

7. The method for determining the value of the 1,1,2,2-tetrachloroethane deuterated solution standard substance as described in claim 5, characterized in that, The nitrogen flow rate in step four is 10 psi.

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