CN106053361A - Spectrum reading and processing method and device of multiple sample cell spectral quantitative analysis - Google Patents

Abstract

The invention discloses a spectrum reading and processing method and device of multiple sample cell spectral quantitative analysis. According to the method, sample cells are divided into reference cells and measuring cells; at first, two kinds of sample cells are both filled with a reference substance; then the sample cells are subjected to spectral scanning to obtain spectrums, which take light intensity as the output and are labeled as Back 0, Back 1, Back 2,..., Back N. During the object analysis process, the reference substance in the measuring tanks is replaced by an object to be analyzed; then the spectrums of the measuring tanks and reference cells are scanned in a mode of background spectrum scanning for another time so as to obtain spectrums, which take light intensity as the output and are labeled as meas 0, meas 1, meas 2,..., meas N. Then according to a formula: Absorbi=-log(measi/Backi)+log(meas0/Back0), the data is processed to obtain a absorption spectrum taking absorbance as the output. The provided method has the advantages that the reference difference between the reference cells and measuring cells can be overcome, especially the influence caused by inconformity of window plate absorption spectrums; the deviation caused by drift and deformation of base line is avoided, and the accuracy of analysis results is largely improved.

Description

Spectrum reading and processing method and device for multi-sample cell spectral quantitative analysis

【Technical field】

The invention relates to the field of spectral analysis, in particular to the spectral analysis of the composition and concentration of articles.

【Background technique】

Spectroscopy can achieve quantitative analysis of almost all polar substances. With the development of computer technology, data analysis and processing technology, in recent years, infrared spectroscopy and ultraviolet spectroscopy have begun to be used in the field of online analysis of gas, liquid, and even solid components and concentrations, but there are still many problems in the current application . Let's take gas analysis as an example to illustrate.

1) When the spectral resolution is high, it may cause spectral distortion. When the spectral resolution is high and the number of scans is large, the spectral scanning time is longer. For example, when the spectral resolution is 1cm ^-1 and the number of scans is 8, the time required to obtain a spectral image is about 60 seconds. If the resolution is increased to 0.5cm ^-1 and the number of scans is increased to 32, it will take about 500 seconds to obtain a spectrogram. During the online gas analysis process, the components and their concentrations in the gas to be analyzed are changing all the time. Since the method of obtaining the spectrum is to obtain the background spectrum with the light intensity as the output first, then obtain the absorption spectrum of the gas to be analyzed with the light intensity as the output, and then divide the absorption spectrum by the background spectrum to obtain the output spectrum with the light transmittance, The negative value of the common logarithm of this spectrum is a spectrogram with absorbance as output. In the application of experimental analysis, the composition and concentration of the analyzed gas are generally unchanged during the acquisition of the default spectrum. Obviously, if only one measuring gas chamber is used for on-line spectral analysis of gas, and the gas is always in a flowing state, then this premise is not valid. Therefore, in the process of spectral scanning, due to the change of gas concentration, the spectral graph obtained each time is not the average value of the spectral graph under the same gas composition and the same concentration, which makes the obtained spectrum unstable or even distorted, thus making The results of spectral analysis have large deviations, especially in the case of serious overlap of absorption spectra in the gas mixture to be analyzed.

2) After the spectrometer has been running for a long time, if the environment changes and the background spectrum needs to be re-scanned, data may be lost. Since the conventional spectrometer has only one measuring gas chamber, after working for a long time, if it is found that the environmental parameters have changed greatly and the background spectrum needs to be re-scanned, the gas path of the gas chamber needs to be closed, and the background gas is introduced, and then the background spectrum is scanned. Since the cleaning of the gas chamber takes a long time, generally within a few minutes, the gas to be measured is passed into the gas chamber to stabilize the gas concentration of the measured component, and it also takes several minutes or even longer. Therefore, this method is easy Leading to data loss and poor real-time performance;

3) In addition, in applications such as mine gas monitoring, it is necessary to use multiple gas chambers to obtain gas from multiple tunnels. The time before and after gas collection may be long, about several hours, and it is difficult to ensure that the environmental parameters of the instrument are completely accurate before and after gas collection. consistent, including the concentration of carbon dioxide gas in the environment. Since the measured gas concentration itself is very small, changes in environmental parameters may lead to large deviations in the analysis results.

In order to overcome the above problems, it is possible to consider adding one or even more gas chambers, use one of the gas chambers to be filled with background gas, and use it as the background spectrum to scan the gas chamber, and the other as the measurement gas chamber, that is, when scanning the background spectrum, cut the background gas chamber into In the optical path, the spectrometer obtains the background spectrum Back0 with light intensity as the output, and when analyzing the gas to be measured, the measuring gas chamber is cut into the optical path, at this time, the spectrometer will scan to obtain the measurement spectrum Measij with the light intensity as the output (indicate The i-th measurement gas cell is the spectrum obtained by the j-th measurement), and then execute formula (1) to obtain the spectrum with the absorbance as the output.

Absorbij＝-log(Measij/Back0) formula (1)

In the formula, log(·) is the common logarithm, and Absorbij represents the spectrum with absorbance as the output obtained from the jth measurement of the i-th measuring cell. Invention patents ZL201110091432.4, ZL201410097985.4 and ZL201410119733.7 are all based on this idea. This method can theoretically solve the above problems, but the prerequisite is that the physical parameters of the air chambers must be exactly the same, that is, the dimensions of different air chambers must be almost exactly the same, and the frame materials must also be processed to be exactly the same. However, it is very difficult for window coatings, such as KBr coatings in the mid-infrared spectrum, to be exactly the same. Since the absorption spectra of the windows are not exactly the same, this will bring baseline drift or even distortion to the absorption spectra of the gas as shown in Figure 1, resulting in large deviations in gas analysis concentrations.

【Content of invention】

The purpose of the present invention is to provide a spectrum reading and processing method and device for multi-sample cell spectral quantitative analysis, to overcome the parameter difference between the reference cell and the measurement cell, especially the inconsistency of the absorption spectrum of the window to the absorption spectrum. Impact.

In order to achieve the above object, the present invention uses the following methods to read and process the absorption spectrum:

A spectral reading and processing method for spectral quantitative analysis of multi-sample cells, comprising the following steps:

(1) The sample pool is divided into a reference pool and a measurement pool, the reference pool is marked as 0, and the measurement pool is marked as 1, 2, ... N;

(2) Fill the reference cell and all the measuring cells with the reference substance, and scan the spectrum according to the background spectrum, and obtain the output spectra marked as Back0, Back1, Back2, Back N with light intensity as the output; where Back0 Indicates the spectrum obtained by scanning the reference cell, Back1 represents the spectrum obtained by scanning the No. 1 measuring cell, and so on;

(3) Replace the reference substance in the sample cell with the analyte, then cut the reference cell and the measurement cell into the optical path in turn, and perform spectral scanning to obtain the light intensities marked as meas0, meas1, meas2, and meas N respectively. is the output spectrum; where meas0 represents the spectrum obtained by scanning the reference cell, meas1 represents the spectrum obtained by scanning the No. 1 measuring cell, and so on;

(4) carry out spectral processing according to following formula (2), take absorbance as the absorption spectrum of output;

Absorbi=-log(measi/Backi)+log(meas0/Back0), where i=1, 2,...N formula (2),

In the formula, Absorbi is the absorption spectrum with the absorbance as the output of the measurement cell i.

Further, the background spectrum in the step (2) is a spectrum with wavenumber as the horizontal axis and light intensity as the vertical axis.

Further, in the optical path of step (3), there is only one sample cell at a time.

Further, in the step (3), each time the item is analyzed, the measurement cell must be re-scanned to obtain meas1, meas2, ... meas N; however, the update method of meas0 can be set according to the actual situation.

Further, the update method of meas0 can be selected from the following several methods:

Method 1: Get it every time you analyze;

Method 2: Acquire at fixed time intervals;

Method 3: Determine whether to acquire according to the self-confirmation of the spectrum;

Method 4: Use method 2 and method 3 at the same time, that is, update meas0 if one of the two conditions is met;

Before rescanning the reference pool to get a new meas0, meas0 remains unchanged.

Further, the self-confirmation of the spectrum is to decide whether to update meas0 according to whether the spectrum is drifted or distorted, and if the baseline drifts seriously or the baseline is distorted, reacquire meas0; otherwise, meas0 remains unchanged.

A device for spectral reading and processing of multi-sample cell spectral quantitative analysis, comprising a background gas chamber, multiple measuring gas chambers, a base supporting the background gas chamber and measuring gas chamber, and driving the measuring gas chamber The vertical movement drive mechanism and the rotary motion mechanism for moving and rotating, the upper limit sensor and the lower limit sensor for sensing the position of the measuring gas chamber are further installed on the base; the intake pipe is connected with multiple measuring gas chambers through the pipeline adapter The gas inlet port of each measuring gas chamber is connected to the gas outlet of each measuring gas chamber through a pipeline adapter device. The pipeline adapter device includes M+1 interfaces, wherein one interface is connected to the inlet pipeline Or the gas outlet pipe is connected, and the remaining M ports are respectively connected with the gas inlet or gas outlet of the measuring gas chamber.

Further, the rotary motion mechanism includes a motor, and a pinion gear and a large gear driven by the motor and intermeshed, wherein a plurality of measuring gas chambers pass through the large gear.

Further, the vertical movement driving mechanism includes a motor, a screw and a moving nut, the motor is fixed on the base through the motor mount, the screw is fixedly connected to the output shaft of the motor, and the moving nut is mounted in cooperation with the screw.

Further, the device for spectral reading and processing of multi-sample cell spectral quantitative analysis further includes a connecting mounting plate, and the moving nut is mounted on the connecting mounting plate; the measuring gas chamber and the background gas chamber are fixedly installed On the air chamber installation seat, the air chamber installation seat is fixedly connected with the connection installation plate through screws.

Compared with the prior art, the present invention has at least the following beneficial effects:

The method for reading and processing the spectrum of a multi-sample cell spectrum quantitative analysis provided by the present invention solves the problem that the parameters of the multi-sample cell, especially the light transmission or light absorption characteristics of the window cannot be completely consistent, and the conventional reference spectrum ratio is used. For the problem that it is easy to cause the spectral baseline to drift or even distort, thereby causing the analysis results to be too large; the present invention avoids the deviation caused by the drift and distortion of the baseline, and greatly improves the accuracy of the analysis results (dividing the measured spectrum by the background spectrum to obtain the following The transmittance is the output spectrum, and the negative value of the common logarithm of the spectrum is the output spectrum with absorbance. In multi-sample cell spectrum analysis, the spectrum obtained by measuring the gas cell is divided by the spectrum scanned by the background gas cell to obtain the following: The transmittance is the output spectrum, due to the difference of the window parameters of the two air chambers, the difference between the two is regarded as the absorption spectrum, thereby causing the baseline to drift or even distort. The method proposed by the present invention is to use two air chambers Respectively scan the background spectrum and the measurement spectrum, and then ask for the difference of the absorption spectrum, instead of using conventional two gas chambers to directly divide to obtain the spectrum, so the difference of the window is no longer included in the baseline); meanwhile, the present invention It can solve the problems of easy data loss and poor real-time performance when re-scanning the background spectrum.

Furthermore, if you want to save time, you can set the way to update meas0 according to the actual situation, which is easy to operate.

【Description of drawings】

Fig. 1 takes the background obtained by scanning the background gas chamber as the reference spectrum, the spectrum obtained by measuring the gas chamber as the absorption spectrum, and the spectrum calculated according to formula (1);

Fig. 2 is a schematic diagram of switching three air chambers; wherein (a) is a schematic diagram of the connection of three air chambers arranged vertically, and figure (b) is a schematic diagram of the connection of three air chambers arranged in a triangle; among the figures 1 is two measuring air chambers, 2 is a solenoid valve, 3 is a tee, 4 is an air inlet pipe, 5 is an air outlet pipe, and 6 is a background gas chamber;

Fig. 3(a) is a cross-sectional view of the structure of the gas chamber switching device in the vertical and horizontal movement mode; in the figure, 1 is the first measuring gas chamber, 6 is the background gas chamber, 7 is the motor, 11 is the second measuring gas chamber, and 12 is Base, 13 is a guide rod, 14 is a screw rod, 15 is a movable nut, 16 is a bearing seat, 17 is a lower limit sensor, 18 is an upper limit sensor, 19 is a connection mounting plate, 20 is the air inlet of the measuring air chamber, 21 For the air chamber installation seat, 22 is the air outlet of the measuring air chamber, and 23 is the set screw;

Figure 3(b) is a schematic diagram of the structure of the rotary air chamber switching device. In the figure, 1 is the first measuring air chamber, 2 is the solenoid valve, 3 is the tee, 4 is the inlet pipe, 5 is the outlet pipe, and 6 is the background gas. Air chamber, 7 is the motor, 8 is the pinion gear, 9 is the shaft connected with the external air chamber support fastened together with the three air chambers, 10 is the large gear, and 11 is the second measuring air chamber;

Fig. 4 is the spectrogram with light intensity as the output obtained by two scans of the background gas chamber and the measurement gas chamber;

Fig. 5 is the spectrum with absorbance as the output obtained according to formula (2) and formula (1) respectively.

【detailed description】

The present invention will be described in further detail below in conjunction with the accompanying drawings and embodiments.

A spectral reading and processing method for spectral quantitative analysis of multi-sample cells, comprising the following steps:

(1) Divide the sample cell into a reference cell and a measurement cell, and carry out labeling. The reference cell is marked as 0, and the other measurement cells are marked as 1, 2, ... N in turn;

(2) All sample pools are full of reference matter, and scan the spectrum according to the background spectrum, the background spectrum is the spectrum with the wave number as the horizontal axis and the light intensity as the vertical axis; The output spectra of Back2 and BackN with light intensity as the output; among them, Back0 represents the spectrum obtained by scanning the reference cell, Back1 represents the spectrum obtained by scanning the No. 1 measuring cell, and so on;

(3) In the process of analyzing gas, liquid or solid objects, the reference cell and all the measurement cells filled with the analytes are sequentially cut into the optical path, which can be switched manually or automatically by an automatic device. Ensure that there is only one sample cell in the optical path at a time; scan the spectra of all sample cells again, and obtain the output spectra with light intensity as meas0, meas1, meas2, and measN respectively; where meas0 represents the reference The spectrum obtained by cell scanning, meas1 means the spectrum obtained by scanning the No. 1 measuring cell, and so on for others;

(4) carry out spectral processing according to following formula (2), take absorbance as the absorption spectrum of output;

Absorbi=-log(measi/Backi)+log(meas0/Back0), where i=1, 2,...N formula (2),

In the formula, Absorbi is the absorption spectrum with the absorbance as the output of the measurement cell i.

Further, in the step (3), each time the article is analyzed, the measurement pool must be re-scanned to obtain meas1, meas2, ...; but the update method of meas0 can be set according to the actual situation, from the following Choose one of the ways:

Method 1: Get it every time you analyze;

Method 2: Obtain at a fixed time interval of 0.5 to 8 hours;

Method 3: Determine whether to update meas0 according to whether the spectrum drifts or distorts. If the baseline drifts seriously or the baseline is distorted, then reacquire meas0; otherwise, meas0 remains unchanged.

Method 4: Use method 2 and method 3 at the same time, that is, update meas0 if one of the two conditions is met;

Before rescanning the reference pool to get a new meas0, meas0 remains unchanged.

The embodiment of the present invention will be described in detail below by taking gas Fourier transform infrared spectroscopic analysis with switching of three gas chambers as an example.

Two measuring gas chambers and a background gas chamber of gas composition and concentration online spectroscopic analysis are connected as shown in Figure 2, which can be arranged vertically, as shown in Figure 2 (a); also can be arranged in a triangle, as shown in Figure 2 ( b). The two air inlets of the two measuring air chambers are respectively equipped with a solenoid valve 2, and the solenoid valve 2 is connected with the inlet pipe 4 through the tee 3, and the two air outlets of the two measuring air chambers are directly connected with the air inlet pipe 4 through the tee 3. The gas outlets of the gas path are connected, and the background gas chamber 6 is filled with background gas. For general online analysis of polar molecular gases, the background gas is nitrogen. In this embodiment, the embodiment of the present invention is described by taking the connection mode of the gas chambers arranged vertically as an example.

The cross-sectional view of the switching device for vertical movement and horizontal movement is shown in Figure 3(a), including the first measurement gas chamber 1, the second measurement gas chamber 11 and the background gas chamber 6, linear bearings, vertical movement mechanism, limit sensor etc.; guide rod 13 and bearing seat 16 form a linear bearing, guide rod 13 is fixedly installed on the floor, and bearing seat 16 is fixedly installed on the connection mounting plate 19; motor 7, motor mounting seat, screw rod 14, movable nut 15 form a vertical The moving mechanism, the motor 7 is installed on the motor mounting base, which can carry out continuous forward and reverse rotation, the motor mounting base is fixedly installed on the bottom plate through the set screw 23, the screw rod 14 is fixedly connected with the output shaft of the motor 7, and the movable nut 15 is fixed Installed on the connection mounting plate 19; the first measuring gas chamber 1, the second measuring gas chamber 11 and the background gas chamber 6 are fixedly installed on the gas chamber mounting base 21, and the gas chamber mounting base 21 and the connecting mounting plate 19 are connected by set screws 23 is fixedly connected, and 3 bearing blocks 16 and a nut are also installed on the connection mounting plate 19. The upper limit sensor 18 and the lower limit sensor 17 are fixedly installed on the base 12, and the distance between the sensors is adjusted according to the required vertical displacement. When it is necessary to switch the first measurement gas chamber 1 into the optical path, the control motor 7 rotates forwardly to drive the screw 14 to rotate, and then drives the nut matched with the screw 14 to move upwards, thereby driving the connecting mounting plate 19, the first measurement gas chamber 1 to move forward The center of the linear bearing moves upward until the upper limit sensor 18 detects the in-position signal, that is, the first measuring air chamber 1 is moved to the optical path. At this time, the computer sends a signal to close the solenoid valve of the first measuring air chamber 1 and open the second measuring air chamber. 2. The solenoid valve of the measurement air chamber 11; after scanning the spectrum, the control motor is reversely driven to connect the mounting plate 19, and the two measurement air chambers move downward along the center of the linear bearing until the lower limit sensor 17 detects the signal in place, that is Switch the second measuring gas chamber 11 to the optical path, at this time, the computer sends a signal to close the solenoid valve of the second measuring gas chamber 11 and open the solenoid valve of the first measuring gas chamber 1 . In this way, it goes round and round, so that when the spectrometer scans the spectrum, the gas composition and its concentration in the gas chamber are stable.

The schematic diagram of the switching device in the continuous rotation mode is shown in Figure 3(b). There are two shafts in the middle of the three air chambers, which are fastened to the three air chambers and connected to the outside. In addition, the middle parts of the three air chambers pass through a large gear 10, and the stepping motor 7 rotates under the control of an industrial computer, etc., and the pinion 8 is coaxially connected with the stepping motor 7, so that it rotates synchronously with the stepping motor 7 , the large gear 10 rotates under the drive of the pinion 8 . Since the feed amount of the stepping motor 7 is given in the form of pulses, the stepping motor 7 itself can recognize the angular position of its own rotor. Therefore, any one of the three gas chambers can be switched to the optical path by sending a corresponding number of pulses through the industrial computer, and the number of pulses required to switch from one gas chamber to another can be determined through experiments. Since the three air chambers are at 120° to each other, this can also be determined by the angular position of the stepper motor 7 . If the direction of the motor arrow in the figure is taken as the positive direction, and the first measuring gas chamber 1 is in the optical path, then the second measuring gas chamber 11 can be switched to the optical path by reversing 120 degrees, and then continue to reverse 120 degrees, then The background gas cell 6 can be switched into the light path. To switch the first measuring gas chamber 1 to the optical path again, just turn forward 240 degrees.

Before the spectral analysis of the gas, the three gas chambers are filled with nitrogen, and then according to the above switching function, the three gas chambers are switched to the optical path of the spectrometer in turn, and the spectrum with the light intensity as the output is scanned as the background spectrum. The background spectra are labeled Back0, Back1 and Back2, respectively. Where Back0 is the spectrum of the background gas chamber 6 , and Back1 and Back2 are the background spectra of the first measuring gas chamber 1 and the second measuring gas chamber 11 respectively.

During the process of gas spectrum analysis, the measuring gas chamber is filled with the gas to be measured. When the first measuring gas chamber 1 is cut into the optical path, it is cut off from the gas path, and the second measuring gas chamber 11 is cut into the gas path for gas renewal. The spectrometer scans the spectrum of the first measuring gas chamber 1 to obtain the spectrum Meas1 with light intensity as the output, and then cuts the second measuring gas chamber 11 into the optical path, and cuts the first measuring gas chamber 1 into the gas path. The spectrometer scans the spectrum of the second measuring gas chamber 11 to obtain a spectrum Meas2 whose output is light intensity. If the acquisition of Back0, Back1 and Back2, as well as Meas1 and Meas2 is completed within a short period of time (within 2 hours), it will be processed according to formula (3):

Absorbi=-log(measi/Backi), where i=1, 2 Formula (3)

Absorb1 and Absorb2 are obtained. If the time is longer (more than 3 hours), after obtaining Meas1 and Meas2, cut the gas chamber 3 into the light path again, obtain Meas0 again, and process according to formula (2) to obtain Absorb1 and Absorb2. If the time is within 2 to 3 hours, the user can choose formula (2) or formula (3) for processing.

The background gas chamber 6 and the first measurement gas chamber 1 obtain Back0, Back1, and Meas0 and Meas1 as shown in FIG. 4 . It can be seen from the figure that Back0 and Meas0 basically coincide, and Back1 and Meas1 basically coincide, which shows that the spectrometer is fully warmed up and there is no problem with the experimental procedure; the intensity difference between Back0 and Back1 is large, and the light intensity of Back1 is about 2/3 of Back0 , which shows that there is a large difference in the absorption of the windows of the two gas chambers, and the window of the measurement gas chamber has a strong absorption of the infrared spectrum as a whole.

According to the formulas (2) and (1), the spectra with the absorbance as the output are respectively shown as Absorbance1 and Absorbance2 in FIG. 5 . It can be seen from Figure 5 that the baseline value of Absorbance1 is basically 0, while the baseline of Absorbance2 has an obvious slope. As the wavenumber decreases from 4000cm ^-1 to 400cm ^-1 , the absorbance increases from 0.13 to about 0.3, and The baseline is not a straight line. In the range of 1000cm ^-1 to 1200cm ^-1 , there are three obvious downward peaks, which shows that the spectral baseline obtained according to formula (1) has a large drift and distortion, while according to formula (2) The baseline of the spectrum is very regular, compared with the spectrum obtained by formula (1), it can avoid the deviation caused by the drift and distortion of the baseline.

The time interval for obtaining Meas0 can be determined according to the actual situation. You can set a fixed time interval, or you can decide whether to re-acquire Meas0 through the self-confirmation of the spectrum. If the baseline is found to be distorted, switch the background gas cell to the optical path to reacquire Meas0, otherwise, Meas0 remains unchanged. Whether the baseline is distorted, the judging method can be found in the invention patent "Fourier Transform Infrared Spectral Distortion Identification and Processing Method (ZL201010268039.3)".

Compared with the prior art, the present invention has at least the following beneficial effects:

The method for reading and processing the spectrum of a multi-sample cell spectrum quantitative analysis provided by the present invention solves the problem that the parameters of the multi-sample cell, especially the light absorption characteristics of the windows cannot be completely consistent, and the comparison of the conventional reference spectrum is easily caused. The spectral baseline drifts or even distorts, which leads to the problem that the analysis results are too large; avoids the deviation caused by the baseline drift and distortion, and greatly improves the accuracy of the analysis results (the measured spectrum is divided by the background spectrum to obtain the output at the transmittance Spectrum, the negative value of the common logarithm value of the spectrum is the spectrum with absorbance as the output. In the multi-sample cell spectrum analysis, the spectrum obtained by measuring the gas cell is divided by the spectrum scanned by the background gas cell to obtain the output with the transmittance Spectrum, due to the difference of two gas chamber window parameters, the difference between the two is regarded as the absorption spectrum, thereby making the baseline drift or even distortion. The method proposed by the present invention is by scanning the background spectrum and the background spectrum of the two gas chambers respectively Measure the spectrum, and then calculate the difference of the absorption spectrum, instead of directly dividing the two gas cells to obtain the spectrum, so the difference of the window is no longer included in the baseline); at the same time, it can solve the problem of rescanning the background spectrum , the data is easily lost, and the real-time performance is poor.

Furthermore, if you want to save time, you can set the way to update meas0 according to the actual situation, which is easy to operate.

The above content is a further detailed description of the present invention in conjunction with specific preferred embodiments. It cannot be determined that the specific embodiments of the present invention are limited thereto. Under the present invention, some simple deduction or replacement can also be made, all of which should be regarded as belonging to the scope of patent protection determined by the submitted claims of the present invention.

Claims (10)

1. A spectral reading and processing method of multi-sample cell spectral quantitative analysis, characterized in that: comprising the following steps: (1) The sample pool is divided into a reference pool and a measurement pool, the reference pool is marked as 0, and the measurement pool is marked as 1, 2, ... N; (2) Fill the reference cell and all the measuring cells with the reference substance, and scan the spectrum according to the background spectrum, and obtain the output spectra marked as Back0, Back1, Back2, Back N with light intensity as the output; where Back0 Indicates the spectrum obtained by scanning the reference cell, Back1 represents the spectrum obtained by scanning the No. 1 measuring cell, and so on; (3) Replace the reference substance in the sample cell with the analyte, then cut the reference cell and the measurement cell into the optical path in turn, and perform spectral scanning to obtain the light intensities marked as meas0, meas1, meas2, and meas N respectively. is the output spectrum; where meas0 represents the spectrum obtained by scanning the reference cell, meas1 represents the spectrum obtained by scanning the No. 1 measuring cell, and so on; (4) carry out spectrum processing according to following formula (2), obtain the absorption spectrum with absorbance as output; Absorbi=-log(measi/Backi)+log(meas0/Back0), where i=1, 2, ... N Formula (2), where Absorbi is the absorption spectrum outputted by the absorbance of measuring cell i. 2. The spectrum reading and processing method of a kind of multi-sample cell spectrum quantitative analysis according to claim 1, is characterized in that: the background spectrum in the described step (2) is the horizontal axis with wave number, and the light intensity is the spectrum on the vertical axis. 3. The method for reading and processing spectra of a multi-sample cell spectral quantitative analysis according to claim 1, characterized in that: in the optical path of the step (3), there is only one sample cell at a time. 4. The spectral reading and processing method of a kind of multi-sample cell spectral quantitative analysis according to claim 1, is characterized in that: in described step (3), when carrying out article analysis at every turn, must rescan measuring cell , to obtain meas1, meas2, ... measN; but the update method of meas0 can be set according to the actual situation. 5. the spectral reading and processing method of a kind of multi-sample cell spectral quantitative analysis according to claim 4, is characterized in that: the update mode of described meas0 can be selected from the following several modes: Method 1: Get it every time you analyze; Method 2: Acquire at fixed time intervals; Method 3: Determine whether to acquire according to the self-confirmation of the spectrum; Method 4: Use method 2 and method 3 at the same time, that is, update meas0 if one of the two conditions is met; Before rescanning the reference pool to get a new meas0, meas0 remains unchanged. 6. The spectrum reading and processing method for quantitative analysis of a multi-sample cell spectrum according to claim 5, characterized in that: the self-confirmation of the spectrum is: according to whether the spectrum drifts and distorts to determine whether to Update meas0, if the baseline drifts seriously, or baseline distortion occurs, reacquire meas0; otherwise, meas0 remains unchanged. 7. A device for spectral reading and processing of multi-sample cell spectral quantitative analysis, characterized in that it includes a background gas chamber (6), a plurality of measuring gas chambers (1, 2), and a supporting background gas chamber and the base of the measuring gas chamber, respectively drive the vertical movement drive mechanism and the rotating motion mechanism of the measuring gas chamber to move and rotate, and the upper limit sensor and the lower limit sensor for sensing the position of the measuring gas chamber are further installed on the base; The gas pipeline is connected to the gas inlets of a plurality of measuring gas chambers through a pipeline adapter, and the gas outlet of each measuring gas chamber is connected to the gas outlet pipeline through a pipeline adapter. The pipeline adapter includes: M+1 interfaces, one of which is connected to the inlet pipe or the outlet pipe, and the remaining M interfaces are respectively connected to the gas inlet or the gas outlet of the measuring gas chamber. 8. The device for spectral reading and processing of a multi-sample cell spectral quantitative analysis according to claim 7, characterized in that: the rotary motion mechanism includes a motor and a pinion gear and a large gear that are driven by the motor and mesh with each other. A gear, wherein a plurality of measuring gas chambers pass through the large gear. 9. The device for reading and processing the spectrum of a multi-sample cell spectrum quantitative analysis according to claim 7, characterized in that: the vertical movement drive mechanism includes a motor, a screw and a moving nut, and the motor passes through the motor The mounting seat is fixed on the base, the screw rod is fixedly connected with the output shaft of the motor, and the moving nut is installed in cooperation with the screw rod. 10. The device for reading and processing the spectrum of a multi-sample cell spectral quantitative analysis according to claim 9, characterized in that: it further comprises a connecting mounting plate, and the moving nut is mounted on the connecting mounting plate; The measuring gas chamber and the background gas chamber are fixedly installed on the gas chamber mounting base, and the gas chamber mounting base is fixedly connected with the connecting mounting plate through screws.