JPH0740005B2 - Element identification method by characteristic X-ray spectrum - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention is a characteristic X-ray for identifying an element present by processing the characteristic X-ray spectrum information acquired by an analyzer with a computer. The present invention relates to a method for identifying elements by spectra.

[Prior Art] It has been performed to identify existing elements by processing the characteristic X-ray spectrum information acquired by an analyzer with a computer.

In the conventional method for identifying an element by the characteristic X-ray spectrum, when the degree of coincidence with a peak of the element A having a certain peak among the spectrum peaks is high by comparison using a computer, another peak is determined as this element. If the degree of coincidence with the peak of the other characteristic X-ray of A is high, the presence of the element A is determined, and if the other peak does not coincide with the other characteristic X-ray of the element A, the element A does not exist. It is decided.

[Problems to be Solved by the Invention] However, the degree of coincidence with the characteristic X-ray peak wavelength λa1 of the element A having a certain peak among the spectrum peaks is high,
Even if the other peak has a high degree of coincidence with the other characteristic X-ray peak wavelength λa2 of this element A, one of the peaks actually has the same wavelength as λa1. X-rays, and the other of the peaks may be characteristic X-rays of other elements present in the sample having the same wavelength as λa2.

In such a case, according to the conventional method for identifying an element by the characteristic X-ray spectrum, it is determined that an element that does not exist is an element that exists, and it is not possible to make a highly accurate determination.

It is an object of the present invention to solve such a conventional problem and to provide a method for identifying an element by a characteristic X-ray spectrum, which enables highly accurate determination of an existing element.

[Means for Solving the Problems] Therefore, in the present invention, by comparing the characteristic X-ray spectrum information obtained by the measurement with the stored spectrum information, the element corresponding to the spectrum peak included in the characteristic X-ray spectrum is compared. In the element identification method based on the characteristic X-ray spectrum, the peak included in the characteristic X-ray spectrum corresponds to the α-ray peak of the element and another peak included in the characteristic X-ray spectrum corresponds to the peak of the element. When corresponding to β rays, the intensity of the peak corresponding to the α ray and the intensity of the peak corresponding to the β ray are compared,
When the intensity of the peak corresponding to the α-ray is higher than the intensity of the peak corresponding to the β-ray, the certain element is identified as an existing element.

EXAMPLES Examples of the present invention will be described in detail below with reference to the drawings.

FIG. 5 shows an example of an apparatus for carrying out the present invention. In the figure, 1 is a CPU, 2 is a display device, 3 is an input device, and 4 is an internal memory in which an operation program of the device is stored. A device, 5 is an external storage device, 6 is a recording device, 7 is an X-ray microanalyzer, and 8 is a bus line. element
Qj (j = 1,2, ..., m) first-order Kα, Kβ, Lα, Lβ, Mα, M
Numerical data corresponding to the wavelengths of β, ...
j, D (Kβ) j, D (Lα) j, D (Lβ) j, D (Mα) j, D
When represented by (Mβ) j, ..., One record is stored in the external storage device 5 as follows: data representing the element Qj, K
.., L.beta., etc. representing the types of characteristic X-rays, and D (K.alpha.) j, ..., D (L.beta.) j, ... Element Qj (j = 1,2, ..., m)
Wavelength table data relating to is stored.

Next, the flow of processing using such an apparatus will be described.

The X-ray spectrum data of the sample acquired by the X-ray microanalyzer 7 is stored in the internal storage device 4. First,
Numerical data P1, P2, ..., Pn representing the wavelength of the spectrum peak by processing the spectrum data as shown in step S1 of FIG. 2 showing the flow of processing by the CPU 1.
And peak intensity values I (P1), I (P2), ..., I at each wavelength
Find (Pn).

Hereinafter, step S1 will be described in detail with reference to FIG.

First, the CPU 1 secondarily differentiates the spectrum data signal stored in the internal storage device 4 as shown in step S1-1, and then performs peak search of the secondarily differentiated data as shown in step S1-2. Thus, numerical data P1, P2, ..., Pr (r ≧ n) representing the peak wavelength are obtained. Next, as shown in step S1-3, a range of a certain width ± Δλ (Δλ is, for example, four times the half-value width) centered on each peak wavelength thus obtained is searched by using the CPU1, and the spectrum data is obtained. The wavelengths B'i +, B'i- that minimize the wavelength are calculated, and these wavelengths B'i, B'i- are stored in the internal storage device 4 as the + and-side back ground wavelengths of the i-th peak. Next, as shown in step S1-4, the CPU 1 causes the peak values I '(P1), I' (P2),
…, I '(Pr) is calculated. Then, as shown in step S1-5, by interpolating the values I (B'i +) and I (B'i-) at the background wavelengths B'i + and B'i-, the peak wavelengths Pi Background value I (B
i) is required. Next, as shown in step S1-6, CPU1
The true value I (Pi) at each peak wavelength is obtained by performing the following calculation using the background value I (Bi) at each peak wavelength thus obtained.

I (Pi) = I '(Pi) -I (Bi) Next, as shown in step S1-7, the CPU 1 determines that I (Pi) is I
It is determined whether or not it is significantly larger than (Bi), and it is determined that a peak exists only when it is large, and a total of n values of Pi and I (Pi) are stored in the internal storage device 4.

In this way, numerical data P1, P2,
, Pn and peak intensity values I (P1), I (P
2), ..., I (Pn) is obtained, the CPU 1 reads the wavelength table data stored in the external storage device 5 and compares the data P1, P2, ..., Pn with the wavelength table data. Based on this, as shown in step 2 of FIG. 2, element names that may be present are registered.

Hereinafter, step S2 will be described in detail with reference to FIG. 4 showing the flow.

As shown in step S2-1 in FIG. 4, the CPU 1 sets each Pi to the primary Kα, Kβ, Lα, L of each element Qj (j = 1, 2, ..., M).
Numerical data D (K corresponding to wavelengths of β, Mα, Mβ, ... Lines
α) j, D (Kβ) j, D (Lα) j, D (Lβ) j, D (Mα) j,
It is compared with D (Mβ) j, ... And it is determined whether the difference is less than or equal to a certain value (for example, half of the half width). If it is less than a certain value, the element name, X-ray name, and order (1) are assigned to the peak and registered in the internal storage device 4 in step S2-2. Next, as shown in step S2-3, it is determined whether, among the registered elements, not only the β ray of the element but also the α ray peak is assigned. The element determined to have no α ray assigned to any peak in step S2-3 is deleted from the registered elements in step S2-4. If YES is determined in step S2-3, the process proceeds to step S2-5, and the wavelength of the higher-order X-ray of each element Qj whose registration is maintained is calculated based on the wavelength table data. The wavelength of the higher-order X-ray thus obtained is calculated in step S2
It is compared with each peak wavelength Pi registered in -6.
If there is a difference between the two wavelengths (for example, half the half-value width)
If it is the following, in step S2-7, the element name, the X-ray name, and the higher order are assigned to the peak in an overlapping manner.

Next, as shown in step 3 of FIG. 2, the existence probabilities of the registered identification elements are ranked.

Hereinafter, step 3 will be described in detail with reference to FIG.

First, as shown in step S3-1 of FIG. 1, among the identified registered elements, the following conditions, that is, elements having an element number of 17 (Cl) or less, and the primary line of Kα is It is judged whether or not the element is assigned to the peak, and if this judgment is YES, the existence probability of this element is A
It is registered in the internal storage device 4 as a rank element. If there is an element determined to be NO in step S3-1, the process proceeds to step S3-2. In step S3-2, the following conditions are applied to the remaining elements, that is, elements having element numbers 18 (Ar) to 38 (Sr), and the primary lines of Kα and Kβ are assigned to any of the peaks, Moreover, it is determined whether or not the intensity value of the peak to which Kα is assigned is larger than the intensity value of the peak to which Kβ is assigned, and if YES is determined in this determination, that element is an element whose existence probability is A rank. As internal storage device 4
Is registered (step S3-6). If in step S3-2
If there is an element determined to be NO, then step S3-3
Move to. In step S3-3, for the remaining elements, the primary conditions of Lα and Lβ are assigned to any of the peaks under the following conditions, that is, the element with element number 37 (Rb) or higher, and Lα is assigned. It is determined whether the intensity value of the peak is greater than the intensity value of the peak to which Lβ is assigned. If YES is determined in step S3-3, this element is registered as an element whose existence probability is A rank. (Step S3-6), if NO is determined, the next step S3
-4. In step S3-4, for the remaining elements, the following conditions are assigned, that is, the primary line of Mα and Mβ is assigned to one of the peaks with the element number 72 (Hf) or higher, and Mα is assigned. It is determined whether the intensity value of each peak is larger than the intensity value of the peak to which Mβ is assigned. If YES is determined in step S3-4, this element is registered as an element whose existence probability is rank A (step S3-6), and if NO is determined, the process proceeds to step S3-5. . In step S3-5, for the remaining element, whether the peak of the element determined to be A rank is assigned to the peak assigned to the primary α ray of the element is checked. judge. if,
If NO is determined in step S3-5, the CPU 1 registers this element in the internal storage device 4 as an element whose existence probability is rank B (step S3-7). Also, step S3-5
If it is determined to be YES in this step, this element is registered in the internal storage device 4 as an element whose existence probability is C rank (step S3-8). Next, the CPU 1 reads the stored contents of the internal storage device 4 and displays the identification elements ranked into the existence probabilities A, B, and C as shown in FIG. 6 as shown in step S4 of FIG. Display on device 2.

By the way, when comparing the intensities of α ray and β ray in K ray (or L ray or M ray) of a certain element, there is a rule that the value (intensity) of α ray is always larger than the intensity of β ray. As in step S3-2 and step S3-3 of FIG. 1,
The intensity of the wavelength corresponding to the α ray of the element that may be present is compared with the intensity of the wavelength corresponding to the β ray, and it is determined whether the above law is established, and based on that, the presence of each identified element Since the probability is ranked and displayed, it is possible to know the possibility of the existence of each identification element with high accuracy by looking at this display.

The above-described embodiment is only one embodiment of the present invention and can be modified and implemented.

For example, in the embodiment described above, in step S2-2
After assigning the element name to Pi, in step S2-3 it is determined whether the α ray of the element Qj is also assigned to any peak, and once the element Qj to which the α ray is not assigned is registered. The element name was deleted, but from the beginning, a search was made to see if there was a peak that matched the α-ray of each element Qj, and by registering only the element that has a peak that matched the α-ray, the above The troublesome step of deleting the registered element name may be omitted.

In this case, in step S2-6, the wavelengths of the higher-order X-rays including the primary X-rays other than α-rays and α-rays and
Compare with the wavelength of Pi.

Also, the position of the registered peak (wavelength or energy),
True peak intensity, peak intensity, background intensity,
The background position, the spectrum data of the background position, and the like may be displayed in a list form and displayed or recorded on the display device 2 or the recording device 6.

Furthermore, the registered peak position, true peak intensity, element name assigned to this peak, X-ray name, X-ray order, etc. are displayed in a list form on the display device 2 or the recording device 6 or recorded. It may be done.

EFFECTS OF THE INVENTION According to the present invention, the peaks included in the characteristic X-ray spectrum correspond to the α-ray peaks of the element, and the other peaks included in the characteristic X-ray spectrum are β-rays of the element. In the case of the α-ray, the intensity of the peak corresponding to the α-ray is compared with the intensity of the peak corresponding to the β-ray,
When the intensity of the peak corresponding to the line is higher than the intensity of the peak corresponding to the β-ray, the certain element is identified as an existing element, and thus the element with high hardness can be identified.

[Brief description of drawings]

FIG. 1 is a diagram showing a main part of a flow of one embodiment of the present invention, and FIG. 2 is a diagram showing a whole process flow including the flow of FIG. 1 as a part of its process. FIG. 3 is a flowchart showing details of step S1 of FIG. 2, FIG. 4 is a flowchart showing details of step S2 of FIG. 2, and FIG. 5 is an example of an apparatus for carrying out the present invention. FIG. 6 is a diagram for illustrating the display example by the display device 2. 1: CPU, 2: Display device 3: Input device, 4: Internal storage device 5: External storage device 6: Recording device 7: X-ray microanalyzer 8: Bus line

Claims (1)

[Claims] 1. Element identification by a characteristic X-ray spectrum for identifying an element corresponding to a spectrum peak included in the characteristic X-ray spectrum by comparing the characteristic X-ray spectrum information obtained by measurement with stored spectrum information. In the method, when the peak included in the characteristic X-ray spectrum corresponds to the peak of the α ray of the element and the other peak included in the characteristic X-ray spectrum corresponds to the β ray of the certain element, the α The intensity of the peak corresponding to the line and the intensity of the peak corresponding to the β-ray are compared, and the α
An element identification method using a characteristic X-ray spectrum, characterized in that the certain element is identified as an existing element when the intensity of the peak corresponding to the ray is higher than the intensity of the peak corresponding to the β ray.