A method for eliminating matrix element interference based on energy spectrum analysis

Abstract

The present invention relates to the field of nuclear analysis technology, and specifically discloses a method for eliminating matrix element interference based on energy spectrum analysis, comprising the following steps: a first step: measuring a series of standard solutions of matrix element A, and recording the peak area or peak height S of matrix element A during each measurement. i (A) and the peak area or peak height S of the element B to be measured i (B); Step 2: Establish S i (A) and S i (B); Step 3: Measure a series of standard solutions of the element B to be measured, with concentrations of C i (B); at the same time, record the peak area or peak height S of the element B to be measured in each measurement i (B) 1 And the peak area or peak height S of the matrix element A i (A) 1 ; Step 4: Use S i (A) 1 Substitute S i (A) and S i (B) S in the relation i (A), while using S i (B) 1 Subtract S i (A) and S i (B) S in the relation i (B), we get ΔS i (B); Step 5: By C i (B) and ΔS i (B) Establishing a mathematical relationship, i.e., the final working curve of the element to be measured B after eliminating the interference of the matrix element A. The method of the present invention is widely applicable, simple to use, and can effectively eliminate the interference of the matrix elements.

Description

Technical Field

[0001] The invention belongs to the technical field of nuclear analysis, and in particular relates to a method for eliminating interference of matrix elements based on energy spectrum analysis. Background Art

[0002] The use of X-rays for nondestructive analysis is widespread in nuclear analysis, but complex sample compositions can severely impact measurement accuracy, necessitating the elimination of interference from matrix elements. While numerous reports exist on background subtraction, most are instrument-specific and lack widespread application. Alternatively, these methods only subtract fixed backgrounds, failing to account for dynamic backgrounds. Another approach involves eliminating matrix effects through sample pretreatment, which can damage the sample's original properties and be time-consuming, reducing analytical efficiency.

[0003] Therefore, it is urgent to propose a method based on energy spectrum analysis to eliminate the interference of matrix elements to solve the above problems. Summary of the Invention

[0004] The purpose of the present invention is to provide a method for eliminating interference of matrix elements based on energy spectrum analysis, which can greatly improve the accuracy of measurement and analysis.

[0005] The technical solutions of the present invention are as follows:

[0006] A method for eliminating matrix element interference based on energy spectrum analysis, assuming that the matrix element is A, the element to be measured is B, and the standard sample number i = 1, 2, 3, 4, 5, 6, ...;

[0007] The following steps are involved:

[0008] Step 1: Measure a series of standard solutions of matrix element A and record the peak area or peak height S of matrix element A at each measurement. i (A) and the peak area or peak height S of the element B to be measured i (B);

[0009] Step 2: Establish S based on the measurement results of the first step i (A) and S i (B) relational expression;

[0010] Step 3: Measure a series of standard solutions of element B, with concentrations of C i (B); at the same time, record the peak area or peak height S of the element B to be measured in each measurement i (B) 1 And the peak area or peak height S of the matrix element A i (A) 1 ;

[0011] Step 4: Use the third step to measure S i(A) 1 Substitute S i (A) and S i (B) S in the relation i (A), while using S i (B) 1 Subtract S i (A) and S i (B) S in the relation i (B), we get ΔS i (B);

[0012] ΔS i (B) is the peak area or peak height of the analyte B after background deduction;

[0013] Step 5: From step 3 C i (B) and ΔS of the fourth step i (B) Establishing a mathematical relationship, that is, the final working curve of the element B to be measured after eliminating the interference of the matrix element A.

[0014] In the second step, S i (A) and S i The relationship (B) is:

[0015] S i (B) = k*S i (A)+b,

[0016] k and b are fitting constants.

[0017] In the fourth step, ΔS i (B)=S i (B) 1 -S i (B)=S i (B) 1 -k*S i (A) 1 -b.

[0018] In the fifth step, C i (B) and ΔS i The mathematical relationship of (B) is:

[0019] C i (B) = k1*ΔS i (B)+b1, k1 and b1 are fitting constants;

[0020] Expanded to:

[0021] C i (B)=k1*[S i (B) 1 -k*S i (A) 1 -b]+b1

[0022] That is the final working curve of the element B to be measured after eliminating the interference of the matrix element A.

[0023] Applicable to situations where the measurement target element is affected by other elements.

[0024] It is suitable for measuring the influence of plutonium matrix on zirconium when measuring a small amount of zirconium in plutonium-containing liquid by X-ray fluorescence method, and the influence of tetravalent on hexavalent plutonium when measuring the valence state of plutonium by spectrophotometry.

[0025] The remarkable effects of the present invention are:

[0026] (1) The method of the present invention is widely applicable, simple to use, and can effectively eliminate the interference of matrix elements.

[0027] (2) Practice has proven that the method of the present invention has good applicability, and is particularly suitable for situations where the target element is affected by other elements, such as the effect of the plutonium matrix on the zirconium element when measuring a small amount of zirconium in a plutonium-containing liquid by X-ray fluorescence, and the effect of tetravalent on hexavalent plutonium when measuring the valence state of plutonium by spectrophotometry.

[0028] Good results have been achieved in the determination of impurity zirconium content by X-ray fluorescence method and plutonium valence spectrophotometry method, which have solved the difficulty of being unable to directly measure samples due to interference and omitted the sample nuclide separation step. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 This is the influence curve of the organic phase Y peak on the zirconium peak;

[0030] Figure 2 is the zirconium concentration curve of the organic phase;

[0031] Figure 3 Schematic diagram for verifying the effect of deducting Y interference. DETAILED DESCRIPTION

[0032] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0033] A method for eliminating matrix element interference based on energy spectrum analysis, assuming that the matrix element is A, the element to be measured is B, and the standard sample number i=1, 2, 3, 4, 5, 6, ...; comprises the following steps:

[0034] Step 1: Measure a series of standard solutions of matrix element A and record the peak area or peak height S of matrix element A at each measurement. i (A) and the peak area or peak height S of the element B to be measured i (B);

[0035] Step 2: Establish S based on the measurement results of the first step i (A) and Si (B) is represented by Formula 1:

[0036] S i (B) = k*S i (A) + b, k and b are fitting constants (Formula 1)

[0037] Step 3: Measure a series of standard solutions of element B, with concentrations of C i (B); at the same time, record the peak area or peak height S of the element B to be measured in each measurement i (B) 1 And the peak area or peak height S of the matrix element A i (A) 1 ;

[0038] Step 4: Use the third step to measure S i (A) 1 Substitute S into Formula 1 i (A), while using S i (B) 1 Subtract S from Formula 1 i (B), we get:

[0039] ΔS i (B)=S i (B) 1 -S i (B)=S i (B) 1 -k*S i (A) 1 -b…………(Formula 2)

[0040] Where: ΔS i (B) is the peak area or peak height of the analyte B after background deduction;

[0041] Step 5: From step 3 C i (B) and ΔS of the fourth step i (B) Establish a mathematical relationship, such as Formula 3:

[0042] C i (B) = k1*ΔS i (B)+b1, k1 and b1 are fitting constants (Formula 3)

[0043] Expanded to:

[0044] C i (B)=k1*[S i (B) 1 -k*S i (A) 1 -b]+b1…………(Formula 4)

[0045] Because the interference of matrix element A is completely eliminated after deducting the dynamic background, the mixed solution of matrix element A and analyte element B can be equivalent to the analyte element B solution after deducting the interference. Therefore, the third step is to establish the final working curve by measuring a series of standard solutions of pure analyte element B, as shown in Formula 4.

[0046] Example

[0047] A method for eliminating matrix element interference based on energy spectrum analysis, taking the determination of zirconium impurity content in radioactive solution by X-ray fluorescence as an example, assuming that the matrix is radioactive element Y, the implementation method is as follows:

[0048] Step 1: Measure a series of organic phase Y standard solutions

[0049] The organic phase radioactive element Y series standard solution was measured, with each group measured 6 times, each measurement lasting 600 seconds. The measurement results are shown in Table 1:

[0050] Table 1 Effect of Y on zirconium in organic phase

[0051] Table1 Interference of Y on Zr in organic phase

[0052]

[0053] Note 1: S(Zr): integrated area of zirconium element; S(Zr) / S(Cu): ratio of integrated area of zirconium to copper; Cu is the internal standard element.

[0054] Note 2: The target material of the instrument is copper. The ratio of the zirconium peak area to the copper peak area can eliminate certain system errors and improve measurement stability.

[0055] Note 3: Due to excessive data, the data in Table 1 are the average of six times.

[0056] Step 2: Based on the measurement results of the first step, establish the relationship between S(Zr) / S(Cu) and S(Y) / S(Cu), such as Figure 1 The formula in:

[0057] S(Zr) / S(Cu)=0.0049*S(Y) / S(Cu)+0.0478

[0058] Step 3: Take the organic phase zirconium series standard solution and measure 6 times for each group, each measurement lasting 600s. The measurement results are shown in Table 2:

[0059] Table 2 Zr series standard measurement data

[0060] Table 2Series standard of Zr measurement curve

[0061]

[0062] Step 4: Use the third step to measure S(Y) 1 / S(Cu) 1 Substitution Figure 1 In the formula, S(Y) / S(Cu) is used, and S(Zr) is used 1 / S(Cu) 1 minus Figure 1 The S(Zr) / S(Cu) formula gives:

[0063] ΔS(Zr) / S(Cu)=S(Zr) 1 / S(Cu) 1 -S(Zr) / S(Cu)

[0064] =S(Zr) 1 / S(Cu) 1 -0.0049*S(Y) 1 / S(Cu) 1 -0.0478

[0065] Where: ΔS(Zr) / S(Cu) is the peak area or peak height of the analyte Zr after deducting the background.

[0066] Step 5: Establish a mathematical relationship between C(Zr) in step 3 and ΔS(Zr) / S(Cu) in step 4, such as Figure 2 The formula in:

[0067] C(Zr)=126.91*ΔS(Zr) / S(Cu)-0.5759

[0068] Expanded to:

[0069] C(Zr)=126.91*[S(Zr) 1 / S(Cu) 1 -0.0049*S(Y) 1 / S(Cu) 1 -0.0478]-0.5759

[0070] When measuring the sample, S(Zr) 1 、S(Y) 1 、S(Cu) 1 Substituting into the formula we can get C(Zr).

[0071] Matrix Y interference subtraction and effect verification

[0072] The organic phase mixed solution with the concentration of radioactive element Y of 41.98 mg / L, 104.95 mg / L, 314.85 mg / L, 629.70 mg / L, and 1049.50 mg / L and the concentration of zirconium of 39.20 mg / L was taken. Each group was measured twice, with each measurement lasting 600 seconds. The measurement results are shown in Table 3:

[0073] Table 3 Measurement data of zirconium and Y mixed solution

[0074] Table 3Measurement data of Y and Zr mixed solution

[0075]

[0076] Note 4: S(Cu): integrated area of copper; S(Zr): integrated area of zirconium.

[0077] Take C(Y) in Table 3 as the horizontal coordinate and ΔS(Zr) / S(Cu) as the vertical coordinate to draw a graph, as shown in Figure 3 .

[0078] Depend on Figure 3 It can be seen that when the Y concentration is between 41.98 mg / L and 1049.50 mg / L, ΔS(Zr) / S(Cu) basically does not change with the Y concentration, indicating that the interference of Y is basically eliminated.

[0079] The basic principles, main features and advantages of the present invention are shown and described above. For those skilled in the art, it is obvious that the present invention is not limited to the details of the above exemplary embodiments, and the present invention can be implemented in other specific forms without departing from the spirit or basic features of the present invention.

[0080] The embodiments should therefore be considered in all respects as illustrative and non-restrictive, the scope of the invention being defined by the appended claims rather than the foregoing description, and all changes that come within the meaning and range of equivalents of the claims are intended to be embraced therein. Any reference sign in a claim should not be construed as limiting the claim to which it relates.

[0081] In addition, it should be understood that although this specification is described in terms of implementation methods, not every implementation method contains only one independent technical solution. This narrative method of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other implementation methods that can be understood by those skilled in the art.

Claims

1. A method for eliminating matrix element interference based on energy spectrum analysis, characterized in that: Let the matrix element be A, the element to be measured be B, and the standard sample number i = 1, 2, 3, 4, 5, 6, ...; The following steps are involved: Step 1: Measure a series of standard solutions of matrix element A and record the peak area or peak height S of matrix element A at each measurement. i (A) and the peak area or peak height S of the element B to be measured i (B); Step 2: Establish S based on the measurement results of the first step i (A) and S i (B) relational expression; Step 3: Measure a series of standard solutions of element B, with concentrations of C i (B); at the same time, record the peak area or peak height S of the element B to be measured in each measurement i (B) 1 And the peak area or peak height S of the matrix element A i (A) 1 ; Step 4: Use the third step to measure S i (A) 1 Substitute S i (A) and S i (B) S in the relation i (A), while using S i (B) 1 Subtract S i (A) and S i (B) S in the relation i (B), we get ΔS i (B); ΔS i (B) is the peak area or peak height of the analyte B after background deduction; Step 5: From step 3 C i (B) and ΔS of the fourth step i (B) Establishing a mathematical relationship, that is, the final working curve of the element B to be measured after eliminating the interference of the matrix element A.

2. The method for eliminating matrix element interference based on energy spectrum analysis according to claim 1, characterized in that: In the second step, S i (A) and S i The relationship (B) is: S i (B)=k*S i (A)+b, k and b are fitting constants.

3. The method for eliminating matrix element interference based on energy spectrum analysis according to claim 2, characterized in that: In the fourth step, ΔS i (B)=S i (B) 1 -S i (B)=S i (B) 1 -k*S i (A) 1 -b.

4. The method for eliminating matrix element interference based on energy spectrum analysis according to claim 3, characterized in that: In the fifth step, C i (B) and ΔS i The mathematical relationship of (B) is: C i (B) = k1*ΔS i (B)+b1, k1 and b1 are fitting constants; Expanded to: C i (B)=k1*[S i (B) 1 -k*S i (AND) 1 -b]+b1 That is the final working curve of the element B to be measured after eliminating the interference of the matrix element A.

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