CN213209903U

CN213209903U - Atomic absorption spectrophotometer

Info

Publication number: CN213209903U
Application number: CN202022277892.3U
Authority: CN
Inventors: 刘小冲
Original assignee: Sichuan Zhonghuanbo Environmental Testing Co ltd
Current assignee: Sichuan Zhonghuanbo Environmental Testing Co ltd
Priority date: 2020-10-13
Filing date: 2020-10-13
Publication date: 2021-05-14
Anticipated expiration: 2030-10-13

Abstract

The utility model discloses an atomic absorption spectrophotometer, which belongs to the field of detection and analysis instruments and comprises an excitation light source, an atomizer, a light beam guiding device and a light splitting device, wherein the atomizer is arranged between the excitation light source and the light splitting device; light beam guiding device sets up on vertical slide rail and rather than sliding connection's multiunit slide at the vertical slide rail of atomizer both sides including dividing, sets up servo electric jar, the servo motor of setting on the slide and the speculum of setting at the servo motor output that is connected on vertical slide rail and with the slide, the utility model discloses a mounted position and the cooperation of installation angle of speculum make atomic absorption spectrophotometer can adjust its self test sensitivity by oneself to be applicable to the detection occasion that different sensitivity required. Simultaneously the utility model discloses make the exciting light beam reduce the light intensity loss that leads to owing to exciting light beam reflection on the speculum by a wide margin in its whole light path with the help of the speculum.

Description

Atomic absorption spectrophotometer

Technical Field

The utility model relates to a detection and analysis instrument field, concretely relates to atomic absorption spectrophotometer.

Background

The atomic absorption spectrometry is an analysis method for determining the content of an element to be detected in a sample according to the absorption of ground state atoms on characteristic wavelength light, and is called atomic absorption analysis for short. Instruments used for atomic absorption spectroscopy are called atomic absorption spectrophotometers or atomic absorption spectrometers. Atomic absorption spectrophotometers (also known as atomic absorption spectrometers) can perform elemental analysis of metals based on the effect of atomic vapors in the ground state of a substance on the absorption of characteristic radiation. Generally, atomic absorption spectrophotometers are capable of sensitive and reliable determination of trace amounts or trace elements.

However, since the sensitivity or measurement accuracy of the atomic absorption spectrophotometer is directly related to the absorption degree of atomic vapor to characteristic wavelength light, and the physical range of burnt atomic vapor in the existing atomizer is limited, the light beam emitted from the light source of the existing atomic absorption spectrophotometer can reach the subsequent spectrophotometer only after passing through the atomic vapor once, so that the existing atomic absorption spectrophotometer cannot adjust the test sensitivity thereof, and is suitable for detection occasions with different sensitivity requirements. Therefore, in the field of detection and analysis instruments, an atomic absorption spectrophotometer capable of flexibly adjusting the test sensitivity and accurately detecting specific elements contained in a sample solution is needed.

SUMMERY OF THE UTILITY MODEL

The utility model discloses to prior art's not enough, provided an atomic absorption spectrophotometer, concrete technical scheme is as follows:

an atomic absorption spectrophotometer comprises an excitation light source, an atomizer, a reflecting device and a light splitting device, wherein the atomizer is arranged between the excitation light source and the light splitting device;

the reflecting device comprises vertical sliding rails which are respectively arranged on two sides of the atomizer, a plurality of groups of sliding seats which are arranged on the vertical sliding rails and are in sliding connection with the vertical sliding rails, a servo electric cylinder which is arranged on the vertical sliding rails and is connected with the sliding seats, a servo motor which is arranged on the sliding seats and a reflecting mirror which is arranged at the output end of the servo motor.

Preferably, the excitation light source comprises a rotating table arranged at the front end of the atomizer, a rotating motor arranged at the bottom end of the rotating table and connected with the rotating table, and a xenon lamp light source and a laser which are respectively arranged on the rotating table.

Preferably, a reserved power interface is arranged on the rotating platform.

Preferably, the device further comprises a control panel, and a signal output end of the control panel is electrically connected with the servo electric cylinder and the servo motor respectively.

Preferably, a control module is arranged in the control panel, and an electric cylinder sliding distance control screen electrically connected with the control module is arranged on the control panel.

Preferably, a motor rotation angle control screen electrically connected with the control module is arranged on the control panel.

Preferably, the light output end of the light splitting device is provided with a detector.

Preferably, the detector is a photomultiplier detector or a CCD array detector.

Preferably, the mirrors are all plane mirrors.

Preferably, two ends of the vertical slide rail are provided with limiting blocks.

The utility model discloses following beneficial effect has:

the utility model discloses well atomizer heats and forms sample atom steam back to the sample that awaits measuring, starts laser light source and makes laser light source launch exciting beam. Then, the tester estimates and determines the number of times of the excitation beam passing through the atomic vapor according to the detection occasion and the sensitivity requirement of the test sample, thereby obviously increasing the light energy absorbed by the element to be tested of the sample to the excitation beam. After a tester determines the number of times of passing of the excitation light beam through the atomic vapor, the sliding position of the reflector is adjusted through the servo electric cylinder, and the reflector is rotated through the servo motor after being moved to the proper reflected light ray position. Multiple reflections of the excitation beam by the mirror are thereby achieved, and the excitation beam is caused to pass through the atomic vapor during each reflection. The utility model discloses a mounted position and the cooperation of installation angle of speculum make atomic absorption spectrophotometer can adjust its self test sensitivity by oneself to be applicable to the detection occasion that different sensitivity required, thereby make whole atomic absorption spectrophotometer's detection efficiency realize the maximize.

Drawings

Fig. 1 is a schematic structural diagram of the present invention, in which the number of times of passing atomic vapor by the excitation beam is 1;

FIG. 2 is a schematic structural diagram of the atomic vapor passing frequency of the excitation beam of the present invention being 3 times;

fig. 3 is a schematic control flow diagram of the middle control panel of the present invention.

In the figure: 101-an excitation light source; 102-an atomizer; 103-reflecting means; 104-a light splitting device; 105-a control panel; 106-a detector; 201-vertical slide rail; 202-a slide; 203-servo electric cylinder; 204-a servo motor; 205-a mirror; 206-a limiting block; 301-rotating table; 302-a rotating electrical machine; 303-xenon lamp light source; 304-a laser light source; 305-reserve a power interface; 401-a control module; 402-electric cylinder sliding distance control screen; 403-motor rotation angle control screen; 501-a first mirror; 502-a second mirror; 503-a third mirror; 504-fourth mirror.

Detailed Description

The principles and features of the present invention are described below in conjunction with the following drawings, the examples given are only intended to illustrate the present invention and are not intended to limit the scope of the present invention.

Examples

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. The components of embodiments of the present invention, as generally described and illustrated in the figures herein, may be arranged and designed in a wide variety of different configurations.

Thus, the following detailed description of the embodiments of the present invention, presented in the accompanying drawings, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative efforts belong to the protection scope of the present invention.

Some embodiments of the present invention will be described in detail below with reference to the accompanying drawings. The embodiments described below and the features of the embodiments can be combined with each other without conflict.

In an embodiment of the present invention, an atomic absorption spectrophotometer is provided, as shown in fig. 1, including an excitation light source 101, an atomizer 102, a reflecting device 103, a light splitting device 104, and a detector 106.

Different types of excitation light sources have different application advantages in the actual atomic absorption spectroscopy detection process: when the high-pressure xenon lamp is used as a light source, the high-pressure xenon lamp can emit continuous spectrum with high intensity, the intensity is almost equal in the range of 300-400 nm, the shell of the high-pressure xenon lamp is made of quartz glass, the internal charging pressure of the high-pressure xenon lamp is xenon with 5 times of standard atmospheric pressure, and the pressure can reach 20 times of the standard atmospheric pressure during working. When the laser light source is used as the light source, the excitation light intensity is high, the monochromaticity is good, the sensitivity of fluorescence analysis can be greatly improved, and single molecule detection can be realized.

In order to facilitate the testing personnel to use different light sources for different testing samples and different testing targets during the testing process, in one embodiment, the excitation light source includes a rotating platform 301 disposed at the front end of the monochromator and rotationally connected to the inner wall of the testing housing, and a rotating motor 302 disposed at the bottom end of the rotating platform 301, an output end of the rotating motor 302 is fixedly connected to the bottom end of the rotating platform 301 and drives the rotating platform 301 to rotate, a xenon light source 303 and a laser light source 304 are disposed on the rotating platform 301, and a reserved power interface 305 for the testing personnel to expand other power sources is disposed on the rotating platform 301. The utility model discloses well xenon lamp light source 303, laser light source 304 and reserve power source 305 and adopt unified interface specification to contained angle each other that xenon lamp light source 303, laser light source 304 and between reserving power source 305 is 120. When the light source of different grade type need be chooseed for use to the tester, only need drive rotating electrical machines 302 with the light source that corresponds remove monochromator front end can, improved the utility model discloses a practicality and convenience.

As shown in fig. 1, the atomizer 102 is disposed at the rear end of the excitation light source 101, i.e., downstream in the excitation light beam propagation direction of the excitation light source 101. The process by which the atomizer 102 changes the element to be measured in the sample or sample solution into gaseous ground-state atoms is referred to as "atomization" of the sample. The equipment used to accomplish the atomization of the sample is referred to as the atomizer 102. The method for atomizing the detected element in the sample mainly comprises a flame atomization method and a non-flame atomization method. Flame atomization methods use the heat energy of a flame to convert a sample into gaseous atoms. The non-flame atomization method converts a sample into gaseous atoms by means of electric heating or chemical reduction and the like. The mass of the atomizer 102 itself will typically have a large impact on the sensitivity and accuracy of atomic absorption spectroscopy.

The atomizer 102 in the present embodiment is of the type employed as a flame atomizer 102. Flame atomization mainly comprises two steps: the method comprises the steps of firstly changing a sample solution into fine fog drops, namely, an atomization stage, and then enabling the fog drops to receive energy supplied by flame to form ground-state atomic steam, namely, an atomization stage. The flame atomizer 102 includes an atomizer and a burner, but may include only a burner. The atomizer is used for atomizing a sample or a sample solution into tiny fog drops. The performance of the atomizer affects sensitivity, measurement accuracy, chemical interference, etc., and thus, it is required to have stable spray, fine and uniform droplets, and high atomization efficiency. In a preferred embodiment, the flame atomizer 102 may include a premixing chamber, also known as an atomizing chamber, which functions to further refine the droplets and uniformly mix them with the fuel gas into the flame. The burner of the flame atomizer 102 functions to atomize sample particles entering the flame by forming a flame from the combustion gases under the influence of the combustion gases. The most commonly used flame for atomic absorption spectroscopy is an air-acetylene flame or nitrous oxide. When different combustion gases are used, the slit width and length of the burner should be adjusted to adapt to the combustion rate of different combustion gases to prevent backfire explosion. Compared with the graphite furnace atomizer 102, the flame atomization method has the advantages of simple operation, good reproducibility, large effective optical path and higher sensitivity to most elements, so the application is wider. However, the flame atomization method has low atomization efficiency and insufficient sensitivity, and generally cannot directly analyze a solid sample.

As shown in fig. 1, the reflection device 103 includes vertical sliding rails 201 respectively disposed at two sides of the atomizer 102, a plurality of sets of sliders 202 disposed on the vertical sliding rails 201 and slidably connected thereto, a servo cylinder 203 disposed on the vertical sliding rails 201 and connected to the sliders 202, a servo motor 204 disposed on the sliders 202, and a mirror 205 disposed at an output end of the servo motor 204. In this embodiment, the number of the slide base 202, the servo electric cylinder 203, the servo motor 204, and the reflection mirror 205 is 4, in other embodiments, the number of the slide base 202, the servo electric cylinder 203, the servo motor 204, and the reflection mirror 205 may be 2, 6, and the like, and two ends of the vertical slide rail 201 are further provided with a limit block 206 for limiting the sliding range of the slide base 202.

As shown in fig. 2, the mirror 205 in the present embodiment includes: a first mirror 501 and a second mirror 502, the first mirror 501 and the second mirror 502 being arranged to face the atom vapor and to oppose each other, the first mirror 501 being arranged on a side of the atom vapor facing the light splitting device 104, and the second mirror 502 being arranged on the other side of the atom vapor facing the light source; a third reflector 503 and a fourth reflector 504, wherein said third reflector 503 is arranged between said light source and said atomic vapor and is mounted at the bottom end of first reflector 501, and said fourth reflector 504 is arranged between said atomic vapor and said light splitting device 104 and is mounted at the bottom end of second reflector 502. The first reflector 501 and the second reflector 502, and the third reflector 503 and the fourth reflector 504 are both plane reflectors, and compared with the curved reflector 205, the plane reflectors have simpler structure, lower cost and more convenient angle setting.

When the tester determines the number of times of passing the atomic vapor by the excitation beam to be 1 time according to the detection occasion and the sensitivity requirement of the test sample, the tester drives the servo cylinder 203 to adjust the sliding positions of the first mirror 501 and the second mirror 502, and the third mirror 503 and the fourth mirror 504 are fixed. After the first mirror 501 and the second mirror 502 are moved to the appropriate reflected light line positions, the first mirror 501 and the second mirror 502 are rotated to the appropriate angles by driving the servo motor 204, whereby the excitation light beam emitted from the excitation light source 101 passes through the atomic vapor by reflection of the first mirror 501 and then is directed to the light splitting device 104 by reflection on the second mirror 502, thereby achieving 1 pass of the excitation light beam through the atomic vapor.

When the tester determines the number of times of passing atomic vapor by the excitation beam to be 3 times according to the detection occasion and the sensitivity requirement of the test sample, the tester drives the servo cylinder 203 to adjust the sliding positions of the first mirror 501, the second mirror 502, the third mirror 503 and the fourth mirror 504. After the first mirror 501 and the second mirror 502 and the third mirror 503 and the fourth mirror 504 are moved to the appropriate reflected light line positions, the first mirror 501 and the second mirror 502 and the third mirror 503 and the fourth mirror 504 are rotated to the appropriate angles by driving the servo motor 204. The excitation light beam emitted from the excitation light source 101 passes through the atomic vapor by reflection on the first reflecting mirror 501, then passes through the atomic vapor again and again 2 times by successive reflection on the second reflecting mirror 502 and the third reflecting mirror 503, then impinges on the fourth reflecting mirror 504, and is further emitted toward the light splitting device 104 by reflection on the fourth reflecting mirror 504, thereby realizing 3 passes of the excitation light beam through the atomic vapor.

As shown in fig. 1, the light splitting device 104 of the present invention is a monochromator, and the type adopted by the light splitting device 104 is a grating monochromator, and is disposed between the atomizer 102 and the detector 106, for separating out monochromatic light required for testing in the excitation light source 101, and in other embodiments, a testable person can use a light filter to separate monochromatic light, so as to replace the monochromator in this embodiment. The light splitting device 104 is provided with a light inlet slit and a light outlet slit, the signal intensity is enhanced when the slit width is increased, and the resolution is increased when the slit width is reduced. The dispersive power of the light splitting device 104 and the stray light level are two important performance criteria. The utility model provides a grating monochromator has low stray light to reduce stray light and to fluorescence spectral measurement's interference, have high dispersion ability simultaneously, so that weak fluorescence spectral also can be detected.

Detector 106 sets up at spectroscopic device 104 rear end and truns into the light signal amplification to the signal of telecommunication for accept the collection by the absorptive monochromatic light of sample, the utility model discloses a photoelectric tube, photomultiplier PMT or charge-coupled device array detector CCD are as detector 106. When the utility model adopts the PMT as the detector 106, there are two different detection modes: fluorescence photon counting type detection and analog type detection.

1. The photon counting PMT is suitable for the conditions that the signal of a sample to be detected is very weak and the signal-to-noise ratio needs to be improved by taking the average value of multiple scanning, and has the advantages of higher detection sensitivity and stability, detection and counting of anode pulses caused by each photon, insensitivity to voltage fluctuation of high voltage applied to the PMT, and no requirement on the stability of an amplifier and a power supply of the high voltage. The disadvantage is that it cannot increase its gain by changing the voltage on the PMT; photon counting is also defined within a linear count rate.

2. The analog PMT is an average value of contributions of the respective pulses, and it does not matter whether the pulses arrive at the same time. This has the advantage of increasing its gain by varying the voltage on the PMT, and thus allowing detection over a wide range of signal strengths without concern for nonlinear response. Analog type detectors require that both the amplifier and the high voltage power supply be fairly stable.

The utility model discloses still including the control panel 105 that the testing personnel of being convenient for carried out control to the reflection position and the reflection angle of speculum 205, control panel 105's signal output part is connected with servo electric jar 203 and servo motor 204 electricity respectively. The model of the control panel 105 is MAM200B, a control module 401 is arranged in the control panel 105, an electric cylinder sliding distance control screen 402 electrically connected with the control module 401 is arranged on the control panel 105, and testers can respectively adjust the reflection positions of the first reflector 501, the second reflector 502, the third reflector 503 and the fourth reflector 504 through the electric cylinder sliding distance control screen 402; the control panel 105 is further provided with a motor rotation angle control screen 403 electrically connected to the control module 401, and a tester can adjust the reflection angles of the first reflector 501 and the second reflector 502, and the third reflector 503 and the fourth reflector 504 through the motor rotation angle control screen 403.

The utility model discloses well atomizer 102 heats the sample that awaits measuring and forms sample atom steam after, starts laser source 304 and makes laser source 304 launch exciting beam. Then, the tester estimates and determines the number of times of the excitation beam passing through the atomic vapor according to the detection occasion and the sensitivity requirement of the test sample, thereby obviously increasing the light energy absorbed by the element to be tested of the sample to the excitation beam. After the tester determines the number of times of passing the atomic vapor by the excitation beam, the sliding position of the mirror 205 is adjusted by the servo cylinder 203, and the mirror 205 is rotated by the servo motor 204 after the mirror 205 is moved to an appropriate reflected light line position. Multiple reflections of the excitation beam by the mirror 205 are thereby achieved and the excitation beam is caused to pass through the atomic vapour during each reflection. The utility model discloses a mounted position and the cooperation of installation angle of speculum 205 make atomic absorption spectrophotometer can adjust its self test sensitivity by oneself to be applicable to the detection occasion of different sensitivity requirements. Simultaneously the utility model discloses make exciting light beam reduce the light intensity loss that leads to owing to exciting light beam reflection on reflecting mirror 205 by a wide margin in its whole light path with the help of reflecting mirror 205 to make whole atomic absorption spectrophotometer's detection efficiency realize the maximize.

It is to be noted that, in this document, the terms "comprises", "comprising" or any other variation thereof are intended to cover a non-exclusive inclusion, so that an article or apparatus including a series of elements includes not only those elements but also other elements not explicitly listed or inherent to such article or apparatus. Without further limitation, an element defined by the phrase "comprising … …" does not exclude the presence of additional like elements in the article or device comprising the element.

The above description is only for the preferred embodiment of the present invention, and is not intended to limit the present invention, and any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention should be included within the protection scope of the present invention.

Claims

1. An atomic absorption spectrophotometer is characterized by comprising an excitation light source (101), an atomizer (102), a reflecting device (103) and a light splitting device (104), wherein the atomizer (102) is arranged between the excitation light source (101) and the light splitting device (104);

the reflecting device (103) comprises vertical sliding rails (201) which are respectively arranged on two sides of the atomizer (102), a plurality of groups of sliding seats (202) which are arranged on the vertical sliding rails (201) and are in sliding connection with the vertical sliding rails, servo electric cylinders (203) which are arranged on the vertical sliding rails (201) and are connected with the sliding seats (202), servo motors (204) which are arranged on the sliding seats (202) and reflecting mirrors (205) which are arranged at output ends of the servo motors (204).

2. The atomic absorption spectrophotometer according to claim 1, wherein the excitation light source (101) comprises a rotary table (301) disposed at a front end of the atomizer (102), a rotary motor (302) disposed at a bottom end of the rotary table (301) and connected thereto, and a xenon lamp light source (303) and a laser light source (304) disposed on the rotary table (301).

3. The atomic absorption spectrophotometer according to claim 2, wherein the rotating platform (301) is provided with a reserved power interface (305).

4. The atomic absorption spectrophotometer according to any one of claims 1 to 3, further comprising a control panel (105), wherein signal output terminals of the control panel (105) are electrically connected with the servo electric cylinder (203) and the servo motor (204), respectively.

5. The atomic absorption spectrophotometer according to claim 4, wherein a control module (401) is provided in the control panel (105), and an electric cylinder sliding distance control screen (402) electrically connected to the control module (401) is provided on the control panel (105).

6. The atomic absorption spectrophotometer according to claim 5, wherein the control panel (105) is provided with a motor rotation angle control screen (403) electrically connected to the control module (401).

7. An atomic absorption spectrophotometer according to any one of claims 1 to 3, wherein the light output end of the spectroscopic means (104) is provided with a detector (106).

8. The atomic absorption spectrophotometer according to claim 7, wherein the detector (106) employs a photomultiplier detector or a charged coupled device array detector.

9. The atomic absorption spectrophotometer according to any one of claims 1 to 3, wherein the mirrors (205) are each a planar mirror.

10. The atomic absorption spectrophotometer according to any one of claims 1 to 3, wherein the two ends of the vertical slide rail (201) are provided with a stop block (206).