Analysis method for high blank value in metal sample element detection

Abstract

The invention discloses an analysis method for high blank value of metal sample element detection, and relates to the field of metal sample detection and analys.The analysis method comprises the steps that initial measurement parameters of X-ray fluorescence spectrometry are set; the method comprises the following steps: processing metal sample detection data by adopting corrected experimental parameters of instrument correction data, acquiring component content according to the metal sample detection data to set next detection time, adjusting measurement parameter setting according to the processed metal sample detection data, carrying out multi-group multi-time detection on the same metal sample again, and analyzing the metal sample data. By reasonably distributing time and instrument occupation, the efficiency of measurement, acquisition, statistics and analysis is improved.

Description

Technical Field

[0001] The invention relates to the field of metal sample detection and analysis, and in particular to an analysis method for detecting a metal sample element with a high blank value. Background Art

[0002] There are many reasons why high element blanks and parallelism may occur during testing. Here are some possible reasons and explanations: Contamination of laboratory water, acids, reagents, etc.: Contamination of laboratory water, acids, and reagents may result in excessively high blank values. This is because impurities in these substances may be detected during the test, thereby increasing the blank value.

[0003] Contamination from pretreatment process and containers: If the sample pretreatment process and the containers used are not clean, the blank value may be high. These sources of contamination may introduce additional elements, thus affecting the test results.

[0004] Widespread presence of constant elements in the environment: The widespread presence of constant elements in the environment may lead to large blank values ​​because these elements may be introduced during sample processing and detection.

[0005] The instrument needs to be zeroed after ignition: In some cases, such as when using techniques such as atomic absorption spectroscopy, the instrument needs to be zeroed after ignition, otherwise the blank value may be too high.

[0006] Running a blank test immediately after the standard curve is completed may result in a blank value that is too high, especially when the standard curve concentration is high.

[0007] Glassware washing issues: If the glassware used is not cleaned thoroughly, it may result in high blank values ​​or poor parallelism.

[0008] Reagent selection and quality: The purity of the reagent is related to the blank value and the accuracy of the measurement results. If the reagent quality is poor, the nitrogen content often does not meet the requirements, which may cause the blank value to be high.

[0009] Quality inspection of experimental water and reagents: If the blank value of the experiment is not ideal, it is necessary to inspect the experimental water and reagents to select water and reagents with the lowest nitrogen content to obtain the ideal blank value.

[0010] Improper sample pretreatment and measurement procedures: Cross-contamination of the laboratory environment can also cause contamination of sample blanks.

[0011] Personal factors of the analyst: The analyst may touch the sample, cosmetics, internal and external medications with his hands, or fail to pay attention to personal hygiene, which may cause the sample to be contaminated.

[0012] During the sample detection process, a variety of possible elemental blanks are generated. However, due to the difference in sample excitation efficiency, that is, the excitation efficiency of X-ray fluorescence of different materials is different, the counting rate of samples with complex metal components will be different, affecting the measurement time. Generally speaking, the XRF test cycle is 3-5 working days, and performing multiple measurements is time-consuming and consumable, which is inefficient.

[0013] The present invention adopts correction detection parameters and performs grouping to analyze the possibility of generating blanks with high sample elements. Summary of the invention

[0014] The invention provides an analytical method for detecting a metal sample element with a high blank value, thereby solving the problems of the prior art.

[0015] In a first aspect, the present invention provides an analytical method for detecting a high blank value of a metal sample element, comprising: Set up initial measurement parameters for X-ray fluorescence spectroscopy; Use instrument calibration data to correct measurement parameters, and obtain measurement parameters in an environment that meets the instrument requirements through calibration; Testing of metal samples; Use the modified experimental parameters of the instrument calibration data to process the metal sample test data, and set the next test time based on the component content obtained from the metal sample test data; Adjust the measurement parameter settings according to the processed metal sample detection data, and perform multiple groups of multiple tests on the same metal sample again, wherein the element types involved in the metal sample detection data are counted, the measurement parameters output by the single element blank film detection are called, the coherent influence of the measurement parameter adjustment generated between different elements in the element types involved in the metal sample detection data is analyzed, the redundant values ​​of the coherent influence are corrected, the measurement parameter adjustment amounts of repeated corrections are removed, and the measurement parameter settings of the processed metal sample detection data are output after integration; Analyze metal sample data.

[0016] Furthermore, the method further includes: preparing metal samples, specifically preparing non-powder samples: Drying and pulverizing: First, the sample is dried and pulverized to a uniform size and uniform particle size distribution, and the uniformity and density of the tablets are tested until they meet the sample requirements; Compression: The crushed sample is compressed into uniform tablets, and the uniformity of the compression pressure applied to the sample is tested to obtain tablets with consistent density and thickness.

[0017] Furthermore, the method further includes: preparing metal samples, specifically preparing powder samples: Tablet preparation: Powder samples are analyzed by tablet preparation. The samples are ground to 300-400 mesh and then pressed into discs.

[0018] Furthermore, it also includes calibration of the instrument, including basic calibration and sample calibration: Basic calibration includes energy calibration of X-ray source and detection calibration of detector. Sample calibration is to calibrate the detection instrument using calibration objects. The standard sample data table is obtained in the sample calibration. The standard value measurement values ​​of each element in the standard samples of films with different contents are obtained by comparing different blank films. The obtained standard value measurement values ​​are corrected according to the standard value correction values ​​of the blank films, and the measurement parameters are optimized.

[0019] Furthermore, the sample calibration also includes: calling the linear regression correction model and regression program provided on the detection instrument to perform regression analysis on the content and strength of the film series standard samples, establishing a calibration curve for assisting the quantitative analysis of the metal sample, and calculating the slope of the regression coefficient and storing it in the computer; Among them, the film series standard samples are different blank films.

[0020] Furthermore, when the metal sample is an actual particle filter membrane sample, the blank film and the actual particle filter membrane sample are measured under the same measurement conditions as the standard sample, and the element content in the actual particle filter membrane sample and the blank film is calculated according to the slope of the calibration curve.

[0021] Furthermore, when light elements and trace elements that are greatly affected by the overlap of spectral lines of other elements are detected and analyzed, spectral nuclear analysis is selected, and energy spectrum nuclear analysis is selected for other major elements and elements with relatively small interference from spectral line overlap.

[0022] Further, the specific steps are as follows: According to the set measurement conditions, the analysis method is established and the measurement parameters are optimized, including: dispersion angle 2θ, PHA lower limit, upper limit and characteristic peak, peak background value measurement time, and the corresponding crystal and 2θ angle are selected according to the analysis crystal type configured by the instrument. When it is detected that the content of the analysis component is higher than the preset threshold, that is, when the counting intensity corresponding to the content of the analysis component exceeds the linear range of the instrument counting rate, the attenuator is automatically called.

[0023] Furthermore, when a wavelength dispersion spectrometer is used, the wavelength λ of the X-ray is obtained by rotating the detector by an angle of 2θ.

[0024] Further, executing the correction of the redundant value of the coherent influence specifically includes: In the process of adjusting the measurement parameters, statistics are collected on the excitation efficiencies of different X-ray fluorescence for different types of elements in the metal sample, and corresponding fluorescences matching multiple metal elements are selected and grouped under the condition of meeting the measurement accuracy; Wherein, the metal elements in a group are excited by corresponding fluorescence and meet the preset requirements of counting rate in the same measurement time period; The preset counting rate requirement is used to characterize the measurement accuracy, and the preset counting rate requirement is achieved by setting a preset counting rate lower limit threshold; Different groups perform multiple tests at the same time. The group that completes first performs statistics, and after all groups are completed, the metal sample data is analyzed.

[0025] The analytical method for detecting metal sample elements with high blank values ​​provided by the present invention combines multiple measurements with a long XRF measurement cycle each time into group tests, and groups and counts the corresponding elements of fluorescence excitation that require less measurement time, thereby achieving efficient statistical data and saving time; and improving the efficiency of measurement, collection, statistics, and analysis by reasonably allocating time and instrument occupancy.

[0026] In the technical solution of the present invention, the instrument does not need to be operated for a long time, thus saving consumables. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The drawings described herein are used to provide a further understanding of the embodiments of the present invention, constitute a part of the present invention, and do not constitute a limitation of the embodiments of the present invention. In the drawings: Figure 1 A flow chart of an analytical method for detecting a high blank value of a metal sample element provided by an exemplary embodiment of the present invention. DETAILED DESCRIPTION

[0028] Exemplary embodiments will be described in detail herein, examples of which are shown in the accompanying drawings. When the following description refers to the drawings, the same numbers in different drawings represent the same or similar elements unless otherwise indicated. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present invention. Instead, they are merely examples of devices and methods consistent with some aspects of the present invention as detailed in the appended claims.

[0029] First, the terms involved in the present invention are explained: Blank value refers to the blank test value, and parallelism refers to the fact that in chemical analysis, the high value of the blank test value remains consistent in repeated tests; Blank test: A blank test is a test that is performed without adding a sample, in the same steps and conditions as the test sample. The test result is called the blank value, which is used to deduct the background of the reagent in the sample and the detection limit of the calculation method. The blank value reflects the comprehensive impact of factors such as the noise of the test instrument, impurities in the reagent, and contamination during the environment and operation on the sample measurement, which is directly related to the accuracy of the final result of the measurement.

[0030] Parallel testing: Parallel testing refers to two or more tests performed under repetitive conditions to evaluate the repeatability and precision of test results. The results of parallel testing should have a small degree of dispersion. If the parallel test results are very different, it may indicate that there are problems in the test process.

[0031] Then, for the statistics of the reasons for the high blank values ​​of multiple elements, the XRF method needs to consume a lot of time and instrument occupancy to realize statistical analysis. The present invention conceives that metal elements with the same excitation efficiency are grouped for statistical collection after qualitative detection, and the X-ray fluorescence of multiple metal elements with the same excitation efficiency is selected to further save time. The metal elements that require a long measurement time to meet the counting rate requirements are performed by another group, and then the X-ray fluorescence with high excitation efficiency is selected to excite the metal samples of the group with long measurement time. When performing the measurement of a group of long-time excitation groups, multiple measurements can be performed relative to the excitation of the short-time group. At the same time, after multiple measurements meet the experimental requirements, the instrument of the short-time excitation group can be used to continue to perform multiple measurements of the long-time excitation group. Finally, when there are fewer materials and instruments, the measurement time can be reduced and the efficiency of measurement, collection, statistics and analysis can be improved by reasonably allocating time and instrument occupancy.

[0032] The specific application scenario of the present invention is laboratory detection and analysis of metal samples.

[0033] The present invention provides an analytical method for detecting a metal sample element with a high blank value, aiming to solve the above technical problems in the prior art.

[0034] The technical solution of the present invention and how the technical solution of the present invention solves the above-mentioned technical problems are described in detail below with specific embodiments. The following specific embodiments can be combined with each other, and the same or similar concepts or processes may not be repeated in some embodiments. The embodiments of the present invention will be described below in conjunction with the accompanying drawings.

[0035] First, the reasons for high blank values ​​may be as follows: Instability of experimental results: The blank value fluctuates greatly, and may fluctuate by tens or even hundreds of percent, which will affect the precision and accuracy of the sample measurement results.

[0036] Contamination problem: If the blank value is significantly higher than the normal value, this usually indicates that there is serious contamination in the analytical determination process, resulting in unreliable measurement results of parallel samples.

[0037] Reagent and water problems: A high blank value may be due to the purity of the reagents used or the presence of impurities in the test water that affect the test results. For example, a high blank value for ammonia nitrogen determination in water quality analysis may be related to factors such as contaminated distilled water, incomplete cleaning of test tubes and other instruments, and poor quality of ammonia-free water.

[0038] Laboratory environment and cleanliness of instruments: If the laboratory environment is not clean or the glassware used in the experiment is not clean, the blank value may be high. It is best to clean the laboratory instruments with hydrochloric acid and then rinse them with ultrapure water to ensure the cleanliness of the instruments.

[0039] Influence of instruments and chromatographic columns: In gas chromatography, long-term use of the chromatographic column or contamination of the column head, as well as reagent contamination, may lead to high blank values.

[0040] Influence of measurement medium and acid: In atomic fluorescence detection, the choice and concentration of the measurement medium, the acid used, the amount of reducing agent, and the lamp current may all affect the blank value.

[0041] Operator influence: The analyst may cause sample contamination by touching the sample, using cosmetics, drugs, etc., resulting in a high blank value.

[0042] Embodiment 1: For the statistical analysis of the measurement of various metal sample elements with high blank values, this embodiment provides the following steps: Figure 1 As shown; A1. Set the initial measurement parameters of X-ray fluorescence spectrometry; A2. Use instrument calibration data to correct measurement parameters, and obtain measurement parameters that meet the instrument environment through calibration; A3. Testing of metal samples: A301. Use the modified experimental parameters of the instrument calibration data to process the metal sample test data, and set the next test time based on the component content obtained from the metal sample test data; A302, adjusting the measurement parameter settings according to the processed metal sample test data, and performing multiple groups of tests on the same metal sample again; A311. Count the types of elements involved in the metal sample detection data, call the measurement parameters output by the single element blank film detection, and analyze the coherent influence of the measurement parameter adjustment between different elements in the types of elements involved in the metal sample detection data; A312, correct the redundant values ​​of coherent influence, remove the measurement parameter adjustment of repeated correction, and integrate and output the measurement parameter settings of the processed metal sample detection data; A321. Under the condition of satisfying the measurement accuracy, select and match the corresponding fluorescence of multiple metal elements and group them; A322, different groups perform multiple tests at the same time, and the group that completes first performs statistics; A4. Analyze metal sample data.

[0043] In this embodiment, steps A321 and A322 cooperate with step A311 to realize multiple measurements of the short-time excitation group. After the multiple measurements meet the experimental requirements, the instruments of the short-time excitation group are used to continue to perform multiple measurements of the long-time excitation group. By reasonably allocating time and instrument occupancy, the measurement time is reduced and the measurement, collection, statistics and analysis efficiency are improved.

[0044] In the several embodiments provided by the present invention, it should be understood that the disclosed systems and methods can be implemented in other ways. For example, the system embodiments described above are only schematic, for example, the division of modules is only a logical function division, and there may be other division methods in actual implementation, such as multiple modules or components can be combined or integrated into another system, or some features can be ignored or not executed.

[0045] The modules described as separate components may or may not be physically separated, and the components shown as modules may or may not be physical modules, that is, they may be located in one place or distributed on multiple network modules. Some or all of the modules may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0046] In addition, each functional module in each embodiment of the present invention may be integrated into one processing module, or each module may exist physically separately, or two or more modules may be integrated into one module. The above-mentioned integrated module may be implemented in the form of hardware or in the form of hardware plus software functional modules.

[0047] Those skilled in the art will appreciate that the embodiments of the present invention may be provided as methods or systems. Therefore, the present invention may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware aspects.

[0048] It should also be noted that the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, commodity or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, commodity or device. In the absence of more restrictions, the elements defined by the sentence "comprises a ..." do not exclude the existence of other identical elements in the process, method, commodity or device including the elements.

[0049] The above are only embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent substitution, improvement, etc. made within the spirit and principle of the present invention should be included in the scope of the claims of the present invention.

[0050] Those skilled in the art will readily appreciate other embodiments of the present invention after considering the specification and practicing the invention disclosed herein. The present invention is intended to cover any variations, uses or adaptations of the present invention that follow the general principles of the present invention and include common knowledge or customary techniques in the art that are not disclosed by the present invention. The specification and examples are to be considered exemplary only, and the true scope and spirit of the present invention is indicated by the claims above.

[0051] It should be understood that the present invention is not limited to the exact construction that has been described above and shown in the drawings and that various modifications and changes may be made without departing from the scope thereof. The scope of the present invention is limited only by the appended claims.

Claims

1. An analytical method for detecting high blank values ​​of metal sample elements, characterized in that: include: Set up initial measurement parameters for X-ray fluorescence spectroscopy; Use instrument calibration data to correct measurement parameters, and obtain measurement parameters in an environment that meets the instrument requirements through calibration; Testing of metal samples: Use the modified experimental parameters of the instrument calibration data to process the metal sample test data, and set the next test time based on the component content obtained from the metal sample test data; Adjust the measurement parameter settings according to the processed metal sample detection data, and perform multiple groups of multiple tests on the same metal sample again, wherein the element types involved in the metal sample detection data are counted, the measurement parameters output by the single element blank film detection are called, the coherent influence of the measurement parameter adjustment generated between different elements in the element types involved in the metal sample detection data is analyzed, the redundant values ​​of the coherent influence are corrected, the measurement parameter adjustment amounts of repeated corrections are removed, and the measurement parameter settings of the processed metal sample detection data are output after integration; Analyze metal sample data.

2. The method for analyzing metal sample elements with high blank value detection according to claim 1, characterized in that: Also includes: For metal sample preparation, specifically including the preparation of non-powder samples: Drying and pulverizing: First, the sample is dried and pulverized to a uniform size and uniform particle size distribution, and the uniformity and density of the tablets are tested until they meet the sample requirements; Compression: The crushed sample is compressed into uniform tablets, and the uniformity of the compression pressure applied to the sample is tested to obtain tablets with consistent density and thickness.

3. The method for analyzing metal sample elements with high blank value detection according to claim 2, characterized in that: Also includes: For metal sample preparation, specifically including the preparation of powder samples: Tablet preparation: Powder samples are analyzed by tablet preparation. The samples are ground to 300-400 mesh and then pressed into discs.

4. The method for analyzing a metal sample with a high blank value according to claim 3, characterized in that: It also includes calibration of the instrument, including basic calibration and sample calibration: Basic calibration includes energy calibration of X-ray source and detection calibration of detector. Sample calibration is to calibrate the detection instrument using calibration objects. The standard sample data table is obtained in the sample calibration. The standard value measurement values ​​of each element in the standard samples of films with different contents are obtained by comparing different blank films. The obtained standard value measurement values ​​are corrected according to the standard value correction values ​​of the blank films, and the measurement parameters are optimized.

5. The method for analyzing metal sample elements with high blank value detection according to claim 4, characterized in that: The sample calibration also includes: calling the linear regression correction model and regression program provided on the detection instrument to perform regression analysis on the content and strength of the film series standard samples, establishing a calibration curve to assist the quantitative analysis of the metal samples, and calculating the slope of the regression coefficient and storing it in the computer; Among them, the film series standard samples are different blank films.

6. The method for analyzing metal sample elements with high blank value detection according to claim 5, characterized in that: When the metal sample is an actual particle filter membrane sample, the blank film and the actual particle filter membrane sample are measured under the same measurement conditions as the standard sample, and the element content in the actual particle filter membrane sample and the blank film is calculated based on the slope of the calibration curve.

7. The method for analyzing a metal sample with a high blank value according to claim 6, characterized in that: When detecting and analyzing light elements and trace elements that are greatly affected by the overlap of spectral lines of other elements, spectral nuclear analysis is selected. For other major elements and elements with relatively small interference from spectral line overlap, energy spectrum nuclear analysis is selected.

8. The method for analyzing metal sample elements with high blank value detection according to claim 7, characterized in that: The specific steps are as follows: According to the set measurement conditions, the analysis method is established and the measurement parameters are optimized, including: dispersion angle 2θ, PHA lower limit, upper limit and characteristic peak, peak background value measurement time, and according to the analysis crystal type configured by the instrument, the corresponding crystal and 2θ angle are selected. When it is detected that the content of the analysis component is higher than the preset threshold, that is, when the counting intensity corresponding to the content of the analysis component exceeds the linear range of the instrument counting rate, the attenuator is automatically called.

9. The method for analyzing metal sample elements with high blank value detection according to claim 8, characterized in that: When a wavelength dispersive spectrometer is used, the wavelength λ of the X-ray is obtained by rotating the detector by an angle of 2θ.

10. The method for analyzing a metal sample with a high blank value according to claim 9, characterized in that: The step of correcting the redundant value of the coherent influence specifically includes: In the process of adjusting the measurement parameters, statistics are collected on the excitation efficiencies of different X-ray fluorescence for different types of elements in the metal sample, and corresponding fluorescences matching multiple metal elements are selected and grouped under the condition of meeting the measurement accuracy; Wherein, the metal elements in a group are excited by corresponding fluorescence and meet the preset requirements of counting rate in the same measurement time period; The preset counting rate requirement is used to characterize the measurement accuracy, and the preset counting rate requirement is achieved by setting a preset counting rate lower limit threshold; Different groups perform multiple tests at the same time. The group that completes first performs statistics, and after all groups are completed, the metal sample data is analyzed.

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