Fluorescent x-ray analysis system, information storage medium, liquid sample cell for fluorescent x-ray analysis system, and fluorescent x-ray analysis program

Abstract

This invention reduces the impact of sedimentation components on measurement results while suppressing increased manufacturing costs. A fluorescence X-ray analysis system includes a rotating mechanism for rotating a sample cell and a speed control unit for controlling the rotation speed of the rotating mechanism. The system operates in two modes: a non-stirring measurement mode, in which the detector performs measurements while the rotating mechanism rotates at a constant speed under the control of the speed control unit; and a stirring measurement mode, comprising a stirring period and a post-stirring measurement period. During stirring, the speed control unit rotates the rotating mechanism at a varying speed to stir the liquid sample; during the post-stirring measurement period, the detector performs measurements after the liquid sample has been stirred. The liquid sample cell is used to contain the liquid sample, and the cross-section of the containing space parallel to the bottom surface includes a portion that is not circular about the rotation axis of the sample cell.

Description

Technical Field

[0001] This invention relates to a fluorescence X-ray analysis system, an information storage medium, a liquid sample cell for a fluorescence X-ray analysis system, and a fluorescence X-ray analysis procedure. Background Technology

[0002] Fluorescence X-ray analysis devices are well-known for determining the elements contained in a sample and their concentrations. Fluorescence X-ray analysis devices can analyze samples that are either solids or liquids.

[0003] When analyzing solid samples, accurate analysis may be impossible due to the surface roughness of the solid sample. To mitigate the influence of surface roughness, there is a fluorescence X-ray analysis device that performs measurements while rotating the sample in a plane.

[0004] When analyzing liquid samples, sedimentable components in the sample may precipitate, causing the measurement results to change over time. To prevent sedimentable components from precipitating during the measurement process, there is a fluorescence X-ray analysis device with a stirring blade installed inside the sample cell and rotating within the sample cell (see Patent Documents 1 and 2 below).

[0005] In addition, there is an X-ray diffraction device or spectrophotometer that performs measurements after rotating the sample cell itself filled with the liquid sample (see Patent Documents 3 and 4).

[0006] Existing technical documents Patent documents Patent Document 1: Japanese Utility Model Application Publication No. 52-046791 Patent Document 2: Japanese Patent Publication No. 53-009558 Patent Document 3: Japanese Patent Application Publication No. 10-38772 Patent Document 4: Japanese Patent Application Publication No. 2009-128043 Summary of the Invention

[0007] The problem that the invention aims to solve As described in Patent Documents 1 and 2, when a stirring blade is installed inside the sample cell, an additional mechanism for rotating the stirring blade is required, which increases manufacturing costs. Especially when the stirring blade is rotated using magnetic force, the strong magnetic material contained within the stirring blade can sometimes affect the measurement results.

[0008] Even with a configuration that rotates the sample cell itself, the liquid sample inside a cylindrical sample cell, as described in Patent Documents 3 and 4, may not be adequately agitated.

[0009] This disclosure is made in view of the above-mentioned problems, and its purpose is to provide a fluorescence X-ray analysis system, an information storage medium, a liquid sample cell for a fluorescence X-ray analysis system, and a fluorescence X-ray analysis procedure, which can suppress the increase in manufacturing costs by using a rotating mechanism to mitigate the influence of surface roughness of solid samples, and reduce the influence of precipitation of sedimentary components on the measurement results by thoroughly agitating the liquid sample.

[0010] Technical solutions used to solve the problem (1) A fluorescence X-ray analysis system according to one aspect of this disclosure comprises: a sample stage on which a sample cell having a receiving space for receiving a sample is placed, and having an opening exposing the bottom surface of the sample cell; a rotation mechanism for rotating the sample cell placed on the sample stage; an X-ray source for irradiating X-rays onto the bottom surface from the underside of the sample stage through the opening of the sample stage; a detector for measuring the intensity of fluorescence X-rays generated from the sample; and a speed control unit for controlling the rotation speed of the rotation mechanism, wherein the fluorescence X-ray analysis system is characterized in that the sample cell comprises: a liquid sample cell containing a liquid sample and parallel to the bottom surface. The cross-section of the containing space includes a portion that is not circular about the rotation axis of the sample cell; and a solid sample cell containing a solid sample. The fluorescence X-ray analysis system operates in two modes: a non-stirring measurement mode, in which the detector performs measurements while the rotating mechanism rotates at a constant rotation speed under the control of the speed control unit; and a stirring measurement mode, which includes a stirring period and a post-stirring measurement period, in which the speed control unit rotates the rotating mechanism at a varying rotation speed to stir the liquid sample, and in the post-stirring measurement period, after the liquid sample has been stirred, the detector performs measurements.

[0011] (2) A fluorescence X-ray analysis system according to another aspect of the present disclosure, characterized in that the sample stage is capable of holding the liquid sample cell and the solid sample cell, wherein in the non-stirring measurement mode, the solid sample cell is placed on the sample stage, and in the stirring measurement mode, the liquid sample cell is placed on the sample stage.

[0012] (3) A fluorescence X-ray analysis system according to another aspect of the present disclosure, characterized in that the containment space of the liquid sample cell has a generally cylindrical shape, and the liquid sample cell has one or more fins having a predetermined length in the radial and rotational directions of the containment space.

[0013] (4) A fluorescence X-ray analysis system according to another aspect of the present disclosure, characterized in that the liquid sample cell has a cylindrical portion with a top opening and a cover portion fitted with the opening, wherein the fins are integrally formed with the cover portion.

[0014] (5) A fluorescence X-ray analysis system according to another aspect of the present disclosure, characterized in that the liquid sample cell has a cylindrical portion with an opening on the top surface, and the fins are integrally formed with the cylindrical portion.

[0015] (6) A fluorescence X-ray analysis system according to another aspect of the present disclosure, characterized in that the liquid sample cell has a cylindrical portion with an opening at the top surface, the cylindrical portion and the fins are formed separately, and the fins are fitted into the cylindrical portion.

[0016] (7) A fluorescence X-ray analysis system according to another aspect of this disclosure, characterized in that the cylindrical portion and the fins are formed of the same material.

[0017] (8) A fluorescence X-ray analysis system according to another aspect of this disclosure, characterized in that it further includes the liquid sample cell.

[0018] (9) A fluorescence X-ray analysis system according to another aspect of the present disclosure, characterized in that, during the stirring, the speed control unit issues an instruction to the rotating mechanism to cause the rotation speed to change discontinuously.

[0019] (10) A fluorescence X-ray analysis system according to another aspect of the present disclosure, characterized in that, during the stirring, the speed control unit issues a reverse rotation command after issuing a command to the rotating mechanism for a predetermined time of forward rotation.

[0020] (11) A fluorescence X-ray analysis system according to another aspect of the present disclosure, characterized in that, during the measurement after stirring, the speed control unit issues a command to stop the rotating mechanism.

[0021] (12) A fluorescence X-ray analysis system according to another aspect of the present disclosure, characterized in that, during the measurement after stirring, the speed control unit issues a command to rotate the rotating mechanism.

[0022] (13) A fluorescence X-ray analysis system according to another aspect of the present disclosure, characterized in that, during the measurement after stirring, the speed control unit issues a reverse rotation command after issuing a command to the rotating mechanism for a predetermined time of forward rotation.

[0023] (14) One aspect of this disclosure relates to an information storage medium that is a non-transitory computer-readable information storage medium and stores a fluorescence X-ray analysis program executed by a computer used by a fluorescence X-ray analysis system, characterized in that the fluorescence X-ray analysis system comprises: a sample stage on which a sample cell having a receiving space for receiving a sample is placed, and having an opening that exposes the bottom surface of the sample cell; a rotation mechanism for rotating the sample cell placed on the sample stage; an X-ray source for irradiating X-rays from the underside of the sample stage through the opening of the sample stage to the bottom surface; a detector for measuring the intensity of fluorescence X-rays generated from the sample; and a speed control unit for controlling the rotation speed of the rotation mechanism, wherein the sample cell contains... Includes: a liquid sample cell containing a liquid sample, and the cross-section of the containing space parallel to the bottom surface includes a portion that is not circular about the rotation axis of the sample cell; and a solid sample cell containing a solid sample. The fluorescence X-ray analysis program causes the computer to execute an operation mode comprising two modes: a non-stirring measurement mode, in which the detector performs measurements while the rotating mechanism rotates at a constant rotational speed under the control of the speed control unit; and a stirring measurement mode, comprising a measurement period during stirring and a measurement period after stirring, in which the speed control unit causes the rotating mechanism to rotate at a varying rotational speed to stir the liquid sample, and in the measurement period after stirring, the detector performs measurements after the liquid sample has been stirred.

[0024] (15) An information storage medium according to another aspect of this disclosure, characterized in that the stirring measurement mode alternately includes the stirring period and the post-stirring measurement period, and the fluorescence X-ray analysis program, when executing the stirring measurement mode, causes the computer to perform the following steps: during the nth post-stirring measurement period, the detector measures the intensity of fluorescence X-rays; during the (n+1)th post-stirring measurement period, the detector measures the intensity of fluorescence X-rays; and based on the fluorescence X-ray intensity measured during the nth post-stirring measurement period and the fluorescence X-ray intensity measured during the (n+1)th post-stirring measurement period, determines whether to set the (n+2)th stirring period.

[0025] (16) According to the information storage medium of another aspect of this disclosure, in the step of the determination, when the difference or ratio between the fluorescence X-ray intensity measured during the nth stirring measurement and the fluorescence X-ray intensity measured during the (n+1)th stirring measurement is greater than a predetermined value, the stirring period of the (n+2)th stirring is set.

[0026] (17) A liquid sample cell according to one aspect of the present disclosure, characterized in that the containing space of the liquid sample cell has a generally cylindrical shape, and the liquid sample cell has one or more fins having a predetermined length in the radial and axial directions of the containing space.

[0027] (18) A liquid sample cell according to another aspect of the present disclosure, characterized in that the liquid sample cell has a cylindrical portion with an opening at the top surface, the cylindrical portion and the fins being formed separately, the fins being fitted into the cylindrical portion.

[0028] (19) A liquid sample cell according to another aspect of the present disclosure, characterized in that the cylindrical portion and the fins are formed of the same material.

[0029] (20) A fluorescence X-ray analysis procedure according to one aspect of this disclosure, executed by a computer used by a fluorescence X-ray analysis system, the fluorescence X-ray analysis system comprising: a sample stage that holds a sample cell having a receiving space for holding a sample and having an opening exposing the bottom surface of the sample cell; a rotation mechanism that rotates the sample cell held on the sample stage; an X-ray source that irradiates X-rays from below the sample stage through the opening of the sample stage onto the bottom surface; a detector that measures the intensity of fluorescence X-rays generated from the sample; and a speed control unit that controls the rotation speed of the rotation mechanism, the sample cell comprising: a liquid sample cell that holds a liquid sample, and the cross-section of the receiving space parallel to the bottom surface comprising not the sample cell. The system comprises a circular portion centered on a rotating axis; and a solid sample cell containing a solid sample. The fluorescence X-ray analysis program causes the computer to execute an operation mode comprising two modes: a non-stirring measurement mode, in which the detector performs measurements while the rotating mechanism rotates at a constant speed under the control of the speed control unit; and a stirring measurement mode, comprising a measurement period during and after stirring, in which the speed control unit causes the rotating mechanism to rotate at a varying speed to stir the liquid sample, and in the measurement period after stirring, the detector performs measurements after the liquid sample has been stirred. Attached Figure Description

[0030] Figure 1 This is a diagram showing the overview of a fluorescence X-ray analysis system.

[0031] Figure 2 This is a top view of the sample stage and the rotating mechanism.

[0032] Figure 3 It is a diagram showing the hardware configuration of an information processing device.

[0033] Figure 4This is a functional block diagram of the arithmetic unit.

[0034] Figure 5 These are top and cross-sectional views of the liquid sample cell.

[0035] Figure 6 These are top and cross-sectional views of the solid sample cell.

[0036] Figure 7 This is a timing diagram used to illustrate the first embodiment.

[0037] Figure 8 This is a flowchart used to illustrate the second embodiment.

[0038] Figure 9 These are the top view and cross-sectional view of the liquid sample cell in Modified Example 1.

[0039] Figure 10 These are the top view and cross-sectional view of the liquid sample cell in Modified Example 2.

[0040] Figure 11 These are the top view and cross-sectional view of the liquid sample cell in variation example 3.

[0041] Figure 12 These are the top view and cross-sectional view of the liquid sample cell in variation example 4. Detailed Implementation

[0042] Hereinafter, preferred embodiments (hereinafter referred to as "embodiments") for carrying out the present invention will be described with reference to the accompanying drawings. Figure 1 This is a schematic diagram showing a cross-section of the fluorescence X-ray analysis system 100 according to this embodiment. Figure 1 As shown, the fluorescence X-ray analysis system 100 includes: a sample stage 102, a rotation mechanism 104, an X-ray source 106, a detector 108, and an information processing device 300 (see reference). Figure 3 ).

[0043] X-ray source 106 irradiates the bottom surface of sample stage 102 from below through an opening in sample stage 102. Specifically, X-ray source 106 is disposed on the lower side of sample stage 102. An opening is provided in sample stage 102, and primary X-rays are irradiated from the lower side of sample stage 102 toward the opening.

[0044] The sample stage 102 holds a sample cell and has an opening that exposes the bottom surface of the sample cell. Specifically, for example... Figure 2 This is a top-down view of the sample stage 102 and the rotating mechanism 104 mounted on the sample stage 102. Figure 2As shown, the sample stage 102 has an opening at the location where the sample cell is positioned. This opening is located in the path of the primary X-ray emitted by the X-ray source 106. The sample stage 102 according to this embodiment can hold both a liquid sample cell 500 and a solid sample cell 600. Furthermore, the sample stage 102 may be able to hold only the solid sample cell 600, or it may not be able to hold the liquid sample cell 500.

[0045] The rotation mechanism 104 rotates the sample cell placed on the sample stage 102. Specifically, the rotation mechanism 104 includes, for example, an actuator such as a motor and an annular member disposed in an opening of the sample stage 102. The actuator rotates the annular member via a belt (not shown), thereby causing the rotation mechanism 104 to rotate the sample cell disposed on the sample stage 102 in the XY plane. Furthermore, the horizontal plane of the sample stage 102 surface will be referred to below as the XY plane. Figure 1 The right direction is the X direction, and the forward direction is the Y direction. The direction perpendicular to the XY plane ( Figure 1 The upward direction is set as the Z direction.

[0046] Detector 108 measures the intensity of fluorescent X-rays generated from the sample. Specifically, detector 108 is, for example, a proportional counter tube. Detector 108 is positioned at the incident location of the fluorescent X-rays, detects the fluorescent X-rays, and outputs a pulse signal. The output pulse signal is input to a counting unit, which counts the pulse signal and acquires it as the intensity of the fluorescent X-rays. Data representing the intensity of the fluorescent X-rays counted by the counting unit is sent to information processing device 300.

[0047] Alternatively, a spectroscopic element can be provided for separating fluorescent X-rays of a specified wavelength emitted from the sample. The spectroscopic element is positioned in the path of the primary X-rays or the path of the fluorescent X-rays. Furthermore, the spectroscopic element and detector 108 can be provided for each analyte, or a configuration in which a set of spectroscopic elements and detectors 108 are rotated. When a set of spectroscopic elements and detectors 108 are rotated, a mechanism (goniometer) is provided to rotate the spectroscopic elements and detectors 108.

[0048] The information processing device 300 controls the operation of the rotating mechanism 104 and the X-ray source 106, and analyzes the sample based on the output of the counting unit, displaying and outputting the analysis results. Specifically, the information processing device 300 is, for example, a personal computer. Figure 3 As shown, it includes an arithmetic unit 302, a storage unit 304, a display unit 306, an input / output unit 308, and an internal bus 310.

[0049] The arithmetic unit 302 is a CPU, MPU, etc., which operates according to the program stored in the storage unit 304. Figure 4This is a functional block diagram of the arithmetic unit 302. Functionally, the arithmetic unit 302 includes an analysis unit 402 and a speed control unit 404. The analysis unit 402 controls the operation of the rotating mechanism 104 and the X-ray source 106, and analyzes the sample based on the output of the counting unit. The speed control unit 404 controls the rotation speed of the rotating mechanism 104. The analysis unit 402 and the speed control unit 404 perform the aforementioned functions by executing the fluorescence X-ray analysis program stored in the storage unit 304 through the arithmetic unit 302. Details of the operation of the speed control unit 404 will be described later.

[0050] Storage unit 304 is a non-transitory computer-readable information storage medium that stores a fluorescence X-ray analysis program executed by the computer used by the fluorescence X-ray analysis system 100. Specifically, storage unit 304 is, for example, an information storage medium such as ROM, RAM, or hard disk. Storage unit 304 stores the fluorescence X-ray analysis program executed by arithmetic unit 302. Furthermore, storage unit 304 also functions as working memory of arithmetic unit 302. The fluorescence X-ray analysis program causes information processing device 300 to execute an operation mode including a non-stirring measurement mode (described later) and a stirring measurement mode (described later).

[0051] The display unit 306 is, for example, a liquid crystal display or an organic EL display, which displays information according to the instructions of the arithmetic unit 302.

[0052] The input / output unit 308 includes a keyboard and mouse, which accept user input. Additionally, the input / output unit 308 includes a communication interface such as a network interface or USB port, enabling communication with other computers via wired or wireless communication. The arithmetic unit 302, storage unit 304, display unit 306, and input / output unit 308 are connected via an internal bus 310.

[0053] Furthermore, in the above description, the liquid sample cell 500 and the solid sample cell 600 are not included in the fluorescence X-ray analysis system 100, but the fluorescence X-ray analysis system 100 may also include the liquid sample cell 500 and / or the solid sample cell 600.

[0054] Next, the sample cells involved in this embodiment will be described. The sample cells used in this embodiment include a liquid sample cell 500 and a solid sample cell 600. Figure 5 These are top and cross-sectional views of the liquid sample cell 500 that contains the liquid sample. Figure 6 These are top and cross-sectional views of the solid sample cell 600, which contains solid samples. Both the liquid sample cell 500 and the solid sample cell 600 have space for containing samples.

[0055] The liquid sample cell 500 contains a liquid sample, and the cross-section of the containing space parallel to the bottom surface includes a portion that is not circular about the rotation axis of the sample cell (hereinafter also referred to as the "stirring section"). The stirring section is a part provided for stirring the liquid sample contained in the liquid sample cell 500. Specifically, as... Figure 5 As shown, the liquid sample cell 500 includes: a cylindrical portion with an opening on the top surface, a membrane 502, and fins 504 serving as a stirring section. The cylindrical portion includes an outer component 506 and an inner component 508. The outer component 506 and the inner component 508 have a generally cylindrical shape and openings on their upper and lower sides. The inner component 508 is inserted into the inner side of the outer component 506. The membrane 502 is sandwiched between and fixed to the outer component 506 and the inner component 508, covering the opening on the lower side of the inner component 508. The liquid sample to be analyzed by the fluorescence X-ray analysis system 100 is disposed within the space (accommodation space) enclosed by the membrane 502 and the inner component 508. Since the inner component 508 is generally cylindrical, the accommodation space of the liquid sample cell 500 has a generally cylindrical shape.

[0056] Fins 504 are disposed on the inner side of the cylindrical portion. Specifically, fins 504 have a predetermined length in the radial and rotational axis directions of the receiving space. For example, fins 504 have a predetermined length in the radial (X direction) and rotational axis (Z direction) directions of the receiving space. Fins 504 are arranged from the inner wall of the cylindrical portion (inner part 508) toward the center. Figure 5 In the example shown, fin 504 has a rectangular plate shape, and its length in the Y direction is shorter than its length in the radial and rotational directions. The radial and rotational lengths of the containing space are only required to be sufficient to stir the liquid sample. For example, the radial length of the containing space is preferably about one-third of the diameter of the cylindrical portion. Furthermore, the length in the rotational direction is preferably about one-third of the height of the cylindrical portion.

[0057] Furthermore, the liquid sample cell 500 according to the first embodiment only needs to have at least one fin 504. However, the liquid sample cell 500 preferably has two or more fins 504. Figure 5 In the embodiment shown, the liquid sample cell 500 has two fins 504 that are at different distances from the bottom surface in the direction of rotation (z-axis direction). Figure 5 The fin 504 on the left is located at a lower height from the surface of the film 502 than the fin 504 on the right.

[0058] Furthermore, the shape of fin 504 in the XZ plane is not limited to rectangle; it can also be other shapes. For example, the shape of fin 504 can also be circular or triangular. Furthermore, in Figure 5 In the embodiment shown, the fin 504 may also be wavy or arc-shaped with each side (or part of the side).

[0059] In addition, Figure 5 In the process, the fin 504 is integrally formed with the cylindrical part, but the cylindrical part and the fin 504 can also be formed separately, and then the fin 504 is fitted into the cylindrical part.

[0060] Furthermore, the cylindrical portion and the fins 504 are preferably formed of the same material. By using the same material for the cylindrical portion and the fins 504, the influence of noise other than fluorescent X-rays emitted from the analyte, i.e., the liquid sample, on the analytical accuracy can be reduced.

[0061] The solid sample cell 600 holds solid samples. Specifically, such as... Figure 6 As shown, the solid sample cell 600 has a generally cylindrical shape with an overall opening on the top surface and an opening on the bottom surface smaller than the top surface. A solid sample is contained between the upper and lower bottom surfaces. The solid sample is exposed through the opening on the bottom surface. Furthermore, in the case of analyzing powdered solid samples, a thin film 502 may be provided at the opening on the bottom surface.

[0062] Next, the operation of the fluorescence X-ray analysis system 100 will be described. The fluorescence X-ray analysis system 100 operates in a mode that includes a non-stirring measurement mode and a stirring measurement mode. Figure 7 It is a timing diagram used to illustrate each action mode.

[0063] Figure 7 The upper part indicates the angle of the object being measured by fluorescence X-rays (the angle between the surface of the aforementioned spectrophotometer and the direction of travel of the fluorescence X-rays incident on the detector 108). Figure 7 The middle section indicates the rotational speed of the fluorescence X-ray analysis system 100 when operating in non-stirring measurement mode. Figure 7 The next paragraph indicates the rotational speed of the fluorescence X-ray analysis system 100 when it operates in stirring measurement mode.

[0064] The non-stirring measurement mode is as follows: a solid sample cell 600 is placed on the sample stage 102, and under the control of the speed control unit 404, the detector 108 performs measurements while the rotating mechanism 104 rotates at a constant speed. Specifically, the non-stirring measurement mode only includes the constant speed rotation period. First, in Figure 6 A solid sample, which is the object of measurement, is placed in the solid sample cell 600 shown. The solid sample protrudes from an opening on the bottom surface of the solid sample cell 600. The solid sample cell 600 is placed on the sample stage 102.

[0065] Next, at time t0, the speed control unit 404 sends a command to the rotation mechanism 104 to rotate at a constant speed. Thus, during the period from time t0 to time t1, the solid sample cell 600 rotates in the XY plane. Next, at time t1, the detector 108 begins measuring the intensity of the fluorescent X-rays at the peak angle of spectral line A (arbitrary fluorescent X-ray). During the period from time t1 to time t2, the detector 108 measures the intensity of the fluorescent X-rays at this peak angle. Next, at time t2, the detector 108 stops measuring the intensity of the fluorescent X-rays. During the period from time t2 to time t3, the detector 108 does not measure the intensity of the fluorescent X-rays. Next, at time t3, the detector begins measuring the intensity of the fluorescent X-rays at the background angle of spectral line A (arbitrary fluorescent X-ray). During the period from time t3 to time t4, the detector 108 measures the intensity of the fluorescent X-rays at this background angle. Then, after time t4, the analysis unit 402 analyzes the elements that produce fluorescent X-rays associated with spectral line A based on the fluorescence X-ray intensity at the peak angle and the fluorescence X-ray intensity at the background angle.

[0066] In the non-stirring measurement mode, the rotation speed of the solid sample cell 600 is constant (e.g., 60 rpm). By rotating the surface of the solid sample irradiated by primary X-rays at a constant speed, deviations in analytical results caused by the unevenness of the solid sample surface can be reduced. Furthermore, in the non-stirring measurement mode, a constant rotation speed means that the rotation speed is constant during the period when the detector 108 measures the fluorescence X-ray intensity. That is, even during operation in the non-stirring measurement mode, the rotation speed can vary as long as the detector 108 is not measuring the fluorescence X-ray intensity. For example, even during operation in the non-stirring measurement mode, the rotation speed can vary during the period before the detector 108 begins measuring the fluorescence X-ray intensity (the period from the initial rotation speed to the constant rotation speed), or after the detector 108 ends measuring the fluorescence X-ray intensity. Moreover, the range of constant rotation speeds is the range of rotation speeds that can reduce deviations in analytical accuracy caused by the unevenness of the solid sample surface. For example, even if the speed control unit 404 controls the rotating mechanism 104 to rotate at a constant speed, the rotation speed of the rotating mechanism 104 may vary due to given conditions (changes in temperature or humidity, etc.). Furthermore, the rotation speed of the rotating mechanism 104 may also vary due to its characteristics (manufacturing deviations or reliability, etc.). However, as long as it remains within a rotation speed range that can reduce deviations in analytical accuracy caused by the unevenness of the solid sample surface, even slight variations are contained within the range of a constant rotation speed.

[0067] The stirring measurement mode is a measurement mode used to analyze the liquid sample in the liquid sample cell 500 placed on the sample stage 102. Specifically, the stirring measurement mode includes a measurement period during stirring and a measurement period after stirring.

[0068] The stirring period is the time during which the speed control unit 404 stirs the liquid sample by rotating the rotating mechanism 104 at varying rotational speeds. Specifically, during stirring, the speed control unit 404 issues commands to the rotating mechanism 104 to change the rotational speed discontinuously. For example, during stirring, after issuing a command to rotate the rotating mechanism 104 in the forward direction for a predetermined time, the speed control unit 404 issues a command to rotate in the reverse direction. Forward and reverse are rotational directions in the XY plane, where either direction can be clockwise. Hereinafter, we assume that forward is clockwise and reverse is counterclockwise. Furthermore, positive values ​​represent forward rotational speeds, and negative values ​​represent reverse rotational speeds.

[0069] The post-stirring measurement period is the period during which the detector 108 performs measurements after the liquid sample has been stirred. Specifically, the detector 108 measures the intensity of the fluorescent X-rays generated from the sample during the post-stirring measurement period, following the stirring period. The speed control unit 404 may also issue a command to rotate the rotating mechanism 104 during the post-stirring measurement period. For example, the speed control unit 404 may also issue a command to rotate the rotating mechanism 104 in the reverse direction after issuing a command to rotate it in the forward direction for a predetermined time during the post-stirring measurement period. Furthermore, the speed control unit 404 may also issue a command to stop the rotating mechanism 104 during the post-stirring measurement period.

[0070] exist Figure 7 In the example shown, firstly, in Figure 5 The liquid sample to be measured is disposed in the liquid sample cell 500 shown. The liquid sample cell 500 is disposed on the sample stage 102.

[0071] Next, at time t0, the speed control unit 404 sends a command to the rotating mechanism 104 to rotate clockwise at a predetermined speed (e.g., 60 rpm). As a result, the sample cell begins to rotate clockwise in the XY plane from time t0. Then, after a predetermined time (e.g., 5 seconds), the speed control unit 404 sends a command to the rotating mechanism 104 to rotate counterclockwise at a predetermined speed (e.g., -60 rpm). As a result, the sample cell begins to rotate counterclockwise in the XY plane. Furthermore, the rotation speed can be changed discontinuously from 60 rpm to -60 rpm after a predetermined time from time t0, or it can be changed continuously from 60 rpm to -60 rpm over a certain period of time. Time t1 and rotation speed are set to values ​​sufficient to agitate the liquid sample.

[0072] The speed control unit 404 may issue at least one command to discontinuously change the rotation speed during stirring, but it is preferable to issue multiple commands. Specifically, for example, the speed control unit 404 preferably issues commands to the rotating mechanism 104 alternately to rotate in the forward direction (e.g., rotation speed 60 rpm) and in the reverse direction (e.g., rotation speed -60 rpm) at predetermined intervals (e.g., 5 seconds). Alternatively, for example, the speed control unit 404 may also issue commands to the rotating mechanism 104 alternately to rotate in the forward direction (e.g., rotation speed 60 rpm) and to stop it (rotation speed 0 rpm) at predetermined intervals (e.g., 5 seconds). Figure 7 In the example shown, the period from time t0 to time t1 includes two periods of forward rotation and one period of reverse rotation.

[0073] By changing the rotational speed of the liquid sample pool 500, the liquid sample contained in the liquid sample pool 500 is stirred. Specifically, after the liquid sample pool 500 has been rotating at a constant rotational speed for a sufficient period of time, the liquid sample rotates at the same rotational speed as the liquid sample pool 500. In this state, the relative velocity between the cylindrical portion and the liquid sample is 0. Here, it is assumed that the liquid sample is contained in a cylindrical liquid sample pool 500 without a stirring section. When the rotational speed of the liquid sample pool 500 changes, the liquid sample rotates at the original rotational speed according to the law of inertia. However, in this disclosure, since a stirring section is provided, when the rotational speed of the liquid sample pool 500 changes, the liquid sample near the stirring section is prevented from rotating at the rotational speed according to the law of inertia. As a result, the flow of the liquid sample is disturbed starting from the stirring section, thereby stirring the liquid sample.

[0074] Next, at time t1, detector 108 begins measuring the intensity of the fluorescent X-ray at the peak angle of spectral line A (arbitrary fluorescent X-ray). During the period from time t1 to time t2, detector 108 measures the intensity of the fluorescent X-ray at this peak angle. The speed control unit 404 can also issue a command to rotate the rotating mechanism 104 during the measurement period after stirring. For example, during the period from time t1 to time t2, after issuing a command to rotate the rotating mechanism 104 forward at a predetermined speed (e.g., 30 rpm) for a predetermined time (e.g., 10 seconds), the speed control unit 404 can also issue a command to rotate the rotating mechanism 104 backward at a predetermined speed (e.g., -30 rpm) for a predetermined time (e.g., 10 seconds). Furthermore, the speed control unit 404 can also issue a command to stop the rotating mechanism 104 during the measurement period after stirring.

[0075] At time t1, the liquid sample is in a state of thorough stirring. Therefore, whether to rotate the rotating mechanism 104 during the measurement after stirring is appropriately set based on whether the sedimenting components contained in the liquid sample will precipitate during the measurement after stirring. Figure 7 In the example shown, the period from time t1 to time t2 includes one period of forward rotation and one period of reverse rotation. Furthermore, the forward and reverse rotation speeds during the measurement period after stirring are half the forward and reverse rotation speeds during the stirring period.

[0076] Next, at time t2, detector 108 stops measuring the fluorescence X-ray intensity. During the period from time t2 to time t3, detector 108 does not measure the fluorescence X-ray intensity. The rotational speed during the stirring period from time t2 to time t3 can be the same as or different from the stirring period from time t0 to time t1. Figure 7 In the example shown, the period from time t2 to time t3 includes two forward rotation periods and a reverse rotation period, respectively.

[0077] Next, at time t3, the fluorescence X-ray intensity at the background angle of spectral line A (arbitrary fluorescence X-ray) is measured. During the period from time t3 to time t4, detector 108 measures the fluorescence X-ray intensity at this background angle. The rotation speed during the measurement period after stirring from time t3 to time t4 can be the same as or different from the measurement period after stirring from time t1 to time t2. Figure 7 In the example shown, the period from time t3 to time t4 includes one forward rotation period and one reverse rotation period, respectively.

[0078] Then, after time t4, the analysis unit 402 analyzes the elements that produce fluorescent X-rays associated with spectral line A based on the fluorescence X-ray intensity at the peak angle and the fluorescence X-ray intensity at the background angle.

[0079] As described above, according to this disclosure, by using the rotating mechanism 104 for mitigating the influence of surface roughness of solid samples, it is possible to suppress the increase in manufacturing costs, and by having a stirring section in the liquid sample cell 500, the influence of sedimentation of settling components on the measurement results can be reduced.

[0080] This disclosure can be applied to any type of fluorescence X-ray analysis system 100, including wavelength-dispersive and energy-dispersive systems. Furthermore, the invention is not limited to the above embodiments and various modifications are possible. The configuration of the fluorescence X-ray analysis system 100 described above is an example and is not limited thereto. It can also be replaced with a configuration substantially the same as that shown in the above embodiments, a configuration that performs the same function or effect, or a configuration that achieves the same purpose. For example, in... Figure 7In this setup, the length and number of stirring cycles are preset. However, it is also possible to adjust the length and number of stirring cycles based on analytical results.

[0081] Figure 8 This is a flowchart illustrating the operation of the fluorescence X-ray analysis system 100 in the stirring measurement mode according to the second embodiment. Furthermore, in the second embodiment, the case where only the intensity of the peak angle is measured, and the background intensity near the peak angle is not measured, will be described. First, a pre-stirring measurement is performed (S802). As an initial value, it is assumed that the variable n, representing the number of stirring times, is 0.

[0082] Specifically, firstly, in Figure 5 A liquid sample, intended for measurement, is placed in a liquid sample cell 500. This liquid sample cell 500 is positioned on a sample stage 102. At time S802, the liquid sample cell 500 does not rotate. Then, primary X-rays are irradiated onto the liquid sample, and a detector 108 measures the intensity of the fluorescent X-rays generated from the liquid sample. The intensity measured in S802 is set as I0.

[0083] Next, during stirring, the speed control unit 404 issues a command to the rotating mechanism 104 to cause the rotation speed to change discontinuously (S804). S804 is the command issued during stirring, which is related to... Figure 7 The stirring period contained in each is the same. For example, the stirring period of S804 includes two forward rotation periods and one reverse rotation period.

[0084] Next, a preparatory measurement after stirring is performed (S806). As described later, steps S804-S814 are repeated. S806 is the step where the detector 108 measures the intensity of the fluorescence X-rays during the nth post-stirring measurement; when n is 1, it is the first post-stirring measurement period. Step S806 is similar to... Figure 7 The same measurement period is included after stirring. Detector 108 measures the intensity of fluorescent X-rays generated from the liquid sample. The intensity measured in S806 is set as I1.

[0085] Next, the number of stirring times n is increased (S808). For example, if step S808 is the first time, the number of stirring times, which is 0, is increased to 1.

[0086] Next, based on the fluorescence X-ray intensity measured during the nth stirring measurement and the fluorescence X-ray intensity measured during the (n+1)th stirring measurement, it is determined whether to set a stirring period of (n+2)th time (S810). Specifically, when the difference or ratio between the fluorescence X-ray intensity measured during the nth stirring measurement and the fluorescence X-ray intensity measured during the (n+1)th stirring measurement is greater than a predetermined value, a stirring period of (n+2)th time is set. For example, when n is 1, intensity I0 is measured in S802. Furthermore, the fluorescence X-ray intensity measured during the first stirring measurement is intensity I1 measured in S806. When the difference between intensity I0 and intensity I1 is less than the theoretical intensity standard deviation σI1... calc When the specified multiplier α is reached, proceed to S816; when the multiplier is greater than or equal to the specified multiplier α, proceed to S812. Furthermore, the specified multiplier α is a pre-set value.

[0087] In step S812, it is determined whether the number of stirring times n is greater than the preset maximum number of stirring times. If the number of stirring times n is greater than the maximum number of stirring times, proceed to step S816; otherwise, proceed to step S814. The maximum number of stirring times can be set to any value, such as 10.

[0088] In S814, the intensity I1 is set to the value of intensity I0. Specifically, when the number of stirring times n is 1, the intensity I1 measured in the first S806 is set to the value of intensity I0. Then, S804 is entered again.

[0089] When it is determined in S810 and S812 that the process should proceed to S816, the formal measurement (S816) is performed. The steps of S816 are as follows: Figure 7 The same as the one included in the post-stirring determination period.

[0090] According to the second embodiment, the stirring measurement mode alternately includes a measurement period during stirring and a measurement period after stirring. Furthermore, it includes the following steps: during the nth measurement period after stirring, the detector 108 measures the intensity of fluorescence X-rays; during the (n+1)th measurement period after stirring, the detector 108 measures the intensity of fluorescence X-rays; and based on the fluorescence X-ray intensity measured during the nth and (n+1)th measurements after stirring, it determines whether to set the (n+2)th stirring period.

[0091] When the liquid sample is fully stirred, the difference between strength I0 and strength I1 is less than the theoretical strength standard deviation σI1. calc The specified magnification α. ​​On the other hand, when the liquid sample is not sufficiently stirred, the difference between strength I0 and strength I1 is greater than the theoretical strength standard deviation σI1. calcThe specified magnification factor α. According to the second embodiment, the sample can be analyzed after the necessary and sufficient number of stirring periods.

[0092] [Variation Example 1] Figure 9 These are top views and cross-sectional views of the liquid sample cell 500 according to Modification 1. Modification 1 can be applied to either the first embodiment or the second embodiment. The liquid sample cell 500 according to Modification 1 has: a cylindrical portion with an opening on the top surface and a cover portion 902 fitted with the opening. Furthermore, fins 504 are integrally formed with the cover portion 902. Specifically, the cover portion 902 has: a disc-shaped portion covering the opening on the top surface of the cylindrical portion, two columnar portions extending substantially perpendicularly from the disc-shaped portion, and fins 504 (stirring portions) respectively provided on the two columnar portions. The cover portion 902 fits into the cylindrical portion by arranging the two columnar portions apart by the inner diameter distance of the cylindrical portion. Furthermore, in Figure 9 In the example shown, the fins 504 have the same shape as in the first and second embodiments and are disposed at the same height. The cylindrical portion and the thin film 502 are also the same as in the first and second embodiments.

[0093] According to Modified Example 1, by providing the cover portion 902, the possibility of liquid sample leakage can be reduced. Furthermore, since the cylindrical portion and the thin film 502 involved in Modified Example 1 are the same as those used in the conventional form, it is possible to combine it with the conventional form simply by manufacturing the cover portion 902.

[0094] [Variation Example 2] Figure 10 These are top views and cross-sectional views of the liquid sample cell 500 according to Modification Example 2. Modification Example 2 can be applied to either the first embodiment or the second embodiment. The liquid sample cell 500 according to Modification Example 2 has a cuboid cylindrical portion 1002 instead of the cylindrical portion of the first and second embodiments. The cuboid cylindrical portion 1002 has a sample-accommodating space, just like the cylindrical portion.

[0095] The cuboid cylindrical portion 1002 includes an outer component 506 and an inner component 508. Both the outer component 506 and the inner component 508 have a generally cuboid shape and openings on their upper and lower sides. The inner component 508 is inserted into the inner side of the outer component 506. A membrane 502 is sandwiched between and fixed to the outer component 506 and the inner component 508, covering the opening on the lower side of the inner component 508. A liquid sample to be analyzed by the fluorescence X-ray analysis system 100 is disposed in the space enclosed together with the inner component 508. Because the inner component 508 is generally cuboid, the containing space of the liquid sample cell 500 has a generally cuboid shape.

[0096] Fins 504 are disposed on the inner side of the cylindrical portion. The fins 504 are arranged from the inner wall of the cuboid cylindrical portion 1002 toward the center. The film 502 is the same as in the first and second embodiments.

[0097] According to Modification 2, the corner portions of the inner component 508 and the two fins 504 function as stirring sections. That is, when the rotational speed of the liquid sample pool 500 changes, the liquid sample near the corner is prevented from rotating at its speed according to the law of inertia. As a result, when the rotational speed of the liquid sample pool 500 changes, turbulence is generated in the flow of the liquid sample starting from the stirring sections, thereby stirring the liquid sample. Therefore, stirring can be performed in a shorter time than in the first and second embodiments. Furthermore, in Modification 2, fins 504 are preferably provided, but the fins 504 in Modification 2 can also be omitted.

[0098] [Variation Example 3] Figure 11 These are top views and cross-sectional views of the liquid sample cell 500 involved in Modification Example 3. Modification Example 3 can be applied to either the first embodiment or the second embodiment. The liquid sample cell 500 involved in Modification Example 3 is similar to... Figure 5 The difference in the illustrated embodiment lies in the height of the fin 504; otherwise, they are the same. Figure 11 As shown, the two fins 504 are positioned at the same height (in the Z direction). Furthermore, the height of each fin 504 can be set according to the characteristics of the liquid sample. For example, the heights of the fins 504 can be different or the same depending on the viscosity of the liquid sample, the ease of precipitation of sedimentary components in the sample, etc. Additionally, as mentioned above, the shape of the fins 504 does not necessarily have to be rectangular.

[0099] [Variation Example 4] Figure 12 These are top and cross-sectional views of the sample cell involved in Modification 4. Modification 4 can be applied to either the first or second embodiment. Figure 5 The difference in the illustrated embodiment is that the size of the liquid sample cell 500 allows it to be disposed inside the solid sample cell 600; otherwise, they are the same. In the case of analyzing a liquid sample in Modification 4, the liquid sample cell 500 containing the liquid sample is disposed within the receiving space of the solid sample cell 600, and the solid sample cell 600 is placed on the sample stage 102. On the other hand, in the case of analyzing a solid sample, the solid sample is disposed within the receiving space of the solid sample cell 600, and the solid sample cell 600 is placed on the sample stage 102. In Modification 4, the two fins 504 may also have the same height, and the shape of the fins 504 may not be rectangular.

[0100] In Modification 4, the solid sample cell 600 is placed on the sample stage 102 for both liquid and solid sample analysis. That is, it is not necessary to form the sample stage 102 in a shape capable of accommodating two different sample cells. Furthermore, the device for transporting the sample cell included in the conventional fluorescence X-ray analysis system 100 can be used. Therefore, the structure can be simplified, and the increase in manufacturing costs can be suppressed.

[0101] Explanation of reference numerals in the attached figures 100 Fluorescence X-ray Analysis System 102 Sample stage 104 Rotating mechanism 106 X-ray sources 108 detectors 300 Information Processing Device 302 Computing Unit 304 Storage Department 306 Display Department 308 Input / Output Section 310 internal bus 402 Analysis Department 404 Speed ​​Control Unit 500 liquid sample cell 502 film, 504 fins 506 External components 508 inner components 600 solid sample cell 902 cover, 1002 A rectangular cylindrical part.

Claims

1. A fluorescence X-ray analysis system, characterized in that, have: A sample stage that holds a sample cell with a receiving space for accommodating a sample and has an opening that exposes the bottom surface of the sample cell. A rotating mechanism that rotates the sample cell placed on the sample stage; An X-ray source irradiates the bottom surface with X-rays from below the sample stage through an opening in the sample stage. A detector that measures the intensity of fluorescent X-rays emitted from a sample; as well as The speed control unit controls the rotational speed of the rotating mechanism. The sample cell includes: A liquid sample cell containing a liquid sample, wherein the cross-section of the containing space parallel to the bottom surface includes a portion that is not circular about the rotation axis of the sample cell; and A solid sample cell, which contains solid samples. The fluorescence X-ray analysis system operates in an operating mode that includes the following two modes: In a non-stirring measurement mode, under the control of the speed control unit, the detector performs measurements while the rotating mechanism rotates at a constant speed; and The stirring measurement mode includes a stirring period and a post-stirring measurement period. During the stirring period, the speed control unit causes the rotating mechanism to rotate at a varying rotational speed to stir the liquid sample. During the post-stirring measurement period, the detector performs a measurement after the liquid sample has been stirred.

2. The fluorescence X-ray analysis system according to claim 1, characterized in that, The sample stage is capable of holding the liquid sample cell and the solid sample cell. In the non-stirring measurement mode, the solid sample cell is placed on the sample stage. In the stirring measurement mode, the liquid sample cell is placed on the sample stage.

3. The fluorescence X-ray analysis system according to claim 1 or 2, characterized in that, The liquid sample cell has a generally cylindrical shape. The liquid sample cell has one or more fins, each fin having a specified length in the radial and rotational directions of the containing space.

4. The fluorescence X-ray analysis system according to claim 3, characterized in that, The liquid sample cell has a cylindrical portion with an opening on the top surface and a cover portion that fits into the opening. The fins are integrally formed with the cover.

5. The fluorescence X-ray analysis system according to claim 3, characterized in that, The liquid sample cell has a cylindrical portion with an opening at the top. The fins are integrally formed with the cylindrical portion.

6. The fluorescence X-ray analysis system according to claim 3, characterized in that, The liquid sample cell has a cylindrical portion with an opening at the top. The cylindrical portion and the fins are formed separately. The fins are fitted into the cylindrical portion.

7. The fluorescence X-ray analysis system according to claim 4, characterized in that, The cylindrical portion and the fins are formed of the same material.

8. The fluorescence X-ray analysis system according to claim 1 or 2, characterized in that, It also includes the liquid sample cell.

9. The fluorescence X-ray analysis system according to claim 1, characterized in that, During the stirring process, the speed control unit sends a command to the rotating mechanism to cause the rotation speed to change discontinuously.

10. The fluorescence X-ray analysis system according to claim 1 or 9, characterized in that, During the stirring process, the speed control unit issues a reverse rotation command after issuing a command to the rotating mechanism for a predetermined period of forward rotation.

11. The fluorescence X-ray analysis system according to claim 1 or 9, characterized in that, During the measurement after stirring, the speed control unit issues a command to stop the rotating mechanism.

12. The fluorescence X-ray analysis system according to claim 1 or 9, characterized in that, During the post-stirring measurement, the speed control unit issues a command to rotate the rotating mechanism.

13. The fluorescence X-ray analysis system according to claim 12, characterized in that, During the measurement after stirring, the speed control unit issues a reverse rotation command after issuing a command to the rotating mechanism for a predetermined time of forward rotation.

14. An information storage medium, which is a non-transitory computer-readable information storage medium, and stores a fluorescence X-ray analysis program executed by a computer used by a fluorescence X-ray analysis system, characterized in that, The fluorescence X-ray analysis system has the following features: A sample stage that holds a sample cell with a receiving space for accommodating a sample and has an opening that exposes the bottom surface of the sample cell. A rotating mechanism that rotates the sample cell placed on the sample stage; An X-ray source irradiates the bottom surface with X-rays from below the sample stage through an opening in the sample stage. A detector that measures the intensity of fluorescent X-rays emitted from a sample; as well as The speed control unit controls the rotational speed of the rotating mechanism. The sample cell includes: A liquid sample cell containing a liquid sample, wherein the cross-section of the containing space parallel to the bottom surface includes a portion that is not circular about the rotation axis of the sample cell; and A solid sample cell, which contains solid samples. The fluorescence X-ray analysis program causes the computer to perform an action mode that includes the following two modes: In a non-stirring measurement mode, under the control of the speed control unit, the detector performs measurements while the rotating mechanism rotates at a constant speed; and The stirring measurement mode includes a stirring period and a post-stirring measurement period. During the stirring period, the speed control unit causes the rotating mechanism to rotate at a varying rotational speed to stir the liquid sample. During the post-stirring measurement period, the detector performs a measurement after the liquid sample has been stirred.

15. The information storage medium according to claim 14, characterized in that, The stirring measurement mode alternately includes the measurement period during stirring and the measurement period after stirring. When the fluorescence X-ray analysis program executes the stirring measurement mode, it causes the computer to perform the following steps: During the nth measurement following stirring, the detector measures the intensity of the fluorescent X-rays; During the (n+1)th stirring measurement, the detector measures the intensity of the fluorescent X-rays; as well as Based on the intensity of the fluorescent X-rays measured during the nth stirring and the intensity of the fluorescent X-rays measured during the (n+1)th stirring, it is determined whether to set the (n+2)th stirring period.

16. The information storage medium according to claim 15, characterized in that, In the determination step, when the difference or ratio between the fluorescence X-ray intensity measured during the nth stirring period and the fluorescence X-ray intensity measured during the (n+1)th stirring period is greater than a predetermined value, the (n+2)th stirring period is set.

17. A liquid sample cell for use in the fluorescence X-ray analysis system of claim 1, characterized in that, The liquid sample cell has a generally cylindrical shape. The liquid sample cell has one or more fins, each fin having a specified length in the radial and axial directions of the containing space.

18. The liquid sample cell according to claim 17, characterized in that, The liquid sample cell has a cylindrical portion with an opening at the top. The cylindrical portion and the fins are formed separately. The fins are fitted into the cylindrical portion.

19. The liquid sample cell according to claim 17 or 18, characterized in that, The cylindrical portion and the fins are formed of the same material.

20. A fluorescence X-ray analysis program, characterized in that, Performed by the computer used by the fluorescence X-ray analysis system. The fluorescence X-ray analysis system has the following features: A sample stage that holds a sample cell with a receiving space for accommodating a sample and has an opening that exposes the bottom surface of the sample cell. A rotating mechanism that rotates the sample cell placed on the sample stage; An X-ray source irradiates the bottom surface with X-rays from below the sample stage through an opening in the sample stage. A detector that measures the intensity of fluorescent X-rays emitted from a sample; as well as The speed control unit controls the rotational speed of the rotating mechanism. The sample cell includes: A liquid sample cell containing a liquid sample, wherein the cross-section of the containing space parallel to the bottom surface includes a portion that is not circular about the rotation axis of the sample cell; and A solid sample cell, which contains solid samples. The fluorescence X-ray analysis program causes the computer to perform an action mode that includes the following two modes: In a non-stirring measurement mode, under the control of the speed control unit, the detector performs measurements while the rotating mechanism rotates at a constant speed; and The stirring measurement mode includes a stirring period and a post-stirring measurement period. During the stirring period, the speed control unit causes the rotating mechanism to rotate at a varying rotational speed to stir the liquid sample. During the post-stirring measurement period, the detector performs a measurement after the liquid sample has been stirred.

Images