CN212134486U

CN212134486U - Spectrum appearance

Info

Publication number: CN212134486U
Application number: CN201922502160.7U
Authority: CN
Inventors: 王志琪; 李辰
Original assignee: Shenzhen Zhongtou Huaxun Terahertz Technology Co Ltd; Shenzhen Institute of Terahertz Technology and Innovation
Current assignee: Shenzhen Zhongtou Huaxun Terahertz Technology Co Ltd; Shenzhen Institute of Terahertz Technology and Innovation
Priority date: 2019-12-31
Filing date: 2019-12-31
Publication date: 2020-12-11
Anticipated expiration: 2029-12-31

Abstract

The application is applicable to spectral detection technical field, provides a spectrum appearance, and wherein, the spectrum appearance includes: the device comprises a gas chromatography module, a gas pool, a terahertz module and a signal processing module; the gas chromatography module is used for separating a sample to be detected to obtain a plurality of chromatographic fractions flowing to the gas pool in sequence; the terahertz module is used for generating terahertz beams and irradiating each chromatographic fraction in the gas pool to obtain sample terahertz signals of each chromatographic fraction; the signal processing module is connected with the terahertz module and used for receiving the sample terahertz signal and processing the sample terahertz signal to obtain a gas phase terahertz spectrogram of the sample to be detected, and the technical problem that accurate qualitative detection and quantitative detection cannot be carried out on a mixture with complex components is solved.

Description

Spectrum appearance

Technical Field

The application belongs to the technical field of spectrum detection, and particularly relates to a spectrometer.

Background

The gas chromatograph is an instrument for quantitatively analyzing a multi-component complex mixture by using a chromatographic separation technique and a detection technique. With the development of science and technology, gas chromatography is rapidly developed as a novel separation and analysis technology, and is an instrumental analysis method with high efficiency, good selectivity, high sensitivity and wide application. Gas chromatography is an effective means for substance separation and quantitative analysis, but it has poor ability to characterize and identify structures, and requires multiple detectors to solve the problem of differences in response values of different compounds.

The terahertz spectrum generally refers to electromagnetic waves in the frequency range of 0.1THz to 10THz, between the far infrared and the microwave. Each molecule has a specific vibration energy level and a specific rotation energy level, and can generate a specific absorption spectral line for the terahertz waves. The structure of the compound can be identified by utilizing a terahertz spectrometer method, such as identification of a medicine polymorphism and identification of a chiral medicine; the method has high specificity, can provide accurate identification information, has high detection process speed, is difficult to test the compound in an aqueous solution state when the compound is identified by using a terahertz spectrometer, generally needs a high-purity sample, otherwise, the background formed by impurities possibly interferes the terahertz spectrogram of the sample, and is not beneficial to the analysis of characteristic absorption peaks.

Therefore, both of these detection methods have certain limitations, and cannot perform accurate qualitative detection and quantitative detection on a mixture with complex components.

SUMMERY OF THE UTILITY MODEL

In view of this, the embodiments of the present application provide a spectrometer, which can solve the technical problem that a mixture with complex components cannot be accurately detected qualitatively and quantitatively.

An embodiment of the present application provides a spectrometer, including: the device comprises a gas chromatography module, a gas pool, a terahertz module and a signal processing module; the gas chromatography module is used for separating a sample to be detected to obtain a plurality of chromatographic fractions flowing to the gas pool in sequence; the terahertz module is used for generating terahertz beams and irradiating each chromatographic fraction in the gas pool to obtain sample terahertz signals of each chromatographic fraction; the signal processing module is connected with the terahertz module and used for receiving the sample terahertz signal and processing the sample terahertz signal to obtain a gas phase terahertz spectrogram of the sample to be detected.

In the embodiment of the application, the gas chromatography module and the terahertz module are integrated in the spectrometer at the same time, so that the gas chromatography module can be used for effectively separating a sample to be detected with complex components, and high-purity chromatographic fractions are provided; the method meets the requirement of the terahertz spectrometer on the purity of the sample when identifying the compound, ensures that the gas phase terahertz spectrogram of the sample to be detected, which is obtained according to the sample terahertz signals of the chromatographic fractions acquired by the terahertz module, can be used for accurately qualitatively and quantitatively detecting the sample to be detected with complex components, and improves the accuracy of qualitatively and quantitatively detecting the mixture with complex components.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed to be used in the embodiments or the prior art descriptions will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present application, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without inventive exercise.

FIG. 1 is a schematic diagram of a first structure of a spectrometer provided in an embodiment of the present application;

fig. 2 is a second structural schematic diagram of a spectrometer provided in an embodiment of the present application.

Detailed Description

In the following description, for purposes of explanation and not limitation, specific details are set forth, such as particular system structures, techniques, etc. in order to provide a thorough understanding of the embodiments of the present application. It will be apparent, however, to one skilled in the art that the present application may be practiced in other embodiments that depart from these specific details. In other instances, detailed descriptions of well-known systems, devices, circuits, and methods are omitted so as not to obscure the description of the present application with unnecessary detail.

Therefore, both of these detection methods have certain limitations, and cannot perform qualitative and quantitative detection on a mixture with complex components.

Based on this, the embodiment of the application provides a spectrometer, can combine gas chromatography and terahertz spectroscopy method to realize carrying out qualitative and quantitative detection to the mixture that the composition is complicated.

In order to explain the technical means of the present application, the following description will be given by way of specific examples.

As shown in fig. 1, a schematic diagram of a spectrometer provided in an embodiment of the present application, the spectrometer may include: a gas chromatography module 10, a gas cell 20, a terahertz module 30 and a signal processing module 40.

Wherein, a sample to be detected is separated by the chromatographic column of the gas chromatographic module 10 to obtain a plurality of chromatographic fractions which sequentially flow to the gas cell 20; then, a terahertz module 30 generates a terahertz light beam, and irradiates each chromatographic fraction in the gas cell 20 to obtain a sample terahertz signal of each chromatographic fraction; and then the signal processing module 40 connected with the terahertz module 30 receives the terahertz signal of the sample and processes the terahertz signal of the sample to obtain a gas phase terahertz spectrogram of the sample to be detected.

In some embodiments of the present application, as shown in fig. 2, the gas chromatography module 10 described above may specifically include: a carrier gas unit 101, a sample introduction unit 102, and a separation unit 103.

The carrier gas unit 101 is configured to provide a carrier gas, and may specifically include: a gas source 1011, a first flow rate controller 1012, and a purge dryer 1013.

The carrier gas provided by the gas source 1011 may be an inert gas with a purity greater than a purity threshold, such as nitrogen and argon with a purity greater than 99%, and the carrier gas has good chemical inertness and does not chemically react with the sample to be measured. Generally, the gas source 1011 is a high pressure gas cylinder, and the initial pressure of the supplied carrier gas is about 10 to 15MPa, so that the carrier gas supplied by the gas source 1011 can be decompressed by the first flow rate controller 1012. For example, the first flow rate controller 1012 may include a pressure reducing valve for reducing the pressure of the carrier gas supplied from the gas source 1011 to 0.1 to 0.5 MPa.

In order to maintain the accuracy of the gas chromatography, the flow rate of the carrier gas needs to be controlled within a certain range (e.g., less than 100 mL/min), so that the first flow controller 1012 can also control the carrier gas supplied from the gas source 1011 to be the carrier gas with a set flow rate. Specifically, a pressure-stabilizing valve or a needle valve may be connected in series to the pressure-reducing valve, so as to control the flow rate of the carrier gas to a set flow rate.

Because the influence of the water molecule in the carrier gas to spectral detection is big, consequently, in some embodiments of this application, after obtaining the carrier gas of setting for the velocity of flow, can obtain dry pure carrier gas under the effect of purification dryer 1013, avoid moisture in the carrier gas to influence activity, life-span and the separation efficiency of chromatographic column, avoid simultaneously that moisture in the carrier gas absorbs terahertz wave, influence terahertz module and carry out the accuracy that detects to the sample that awaits measuring. Wherein, silica gel, molecular sieve and active carbon can be filled in the purification dryer 1013 in sequence, so as to meet the requirements for drying and purifying the carrier gas.

The dry and pure carrier gas is used for conveying the gaseous sample to be detected in the sample introduction unit 102 to the separation unit 103 and the gas cell 20.

When the sample to be tested is a gaseous sample to be tested, the sample injection unit 102 may include a conventional syringe, and the specification of the conventional syringe may be 0.25/1/2/5 mL. When the sample to be tested in the sample introduction unit 102 is a liquid sample to be tested, the sample introduction unit 102 may include a micro injector, and the specification of the micro injector may be 1/10/50/100 μ L, and the sample introduction unit 102 may further include: the device comprises a gasification chamber and a heater, wherein the gasification chamber is used for gasifying a liquid sample to be tested, and after the liquid sample to be tested is fed, the liquid sample to be tested is gasified into a gaseous sample to be tested.

In some embodiments of the present application, the sample injection unit 102 may further include a planar six-way valve for quantitative injection of the gaseous sample to be detected.

The separation unit 103 may include: a chromatographic column; after the sample introduction unit 102 delivers the gaseous sample to be detected to the separation unit 103, the gaseous sample to be detected may be separated by a chromatographic column, so as to obtain a plurality of chromatographic fractions.

Wherein, the chromatographic column can be a capillary column. Since the separation effect of the chromatographic column is related to the column length, the column diameter, the column shape, and the like, in the present embodiment, the capillary column may be a capillary column having an inner diameter of 0.1 to 0.5mm and a length of 20 to 60 m.

It should be noted that, in order to prevent the condensation of the gaseous sample to be measured, the chromatographic column may further include an incubator, which can keep the temperature of the spectral column at any temperature of 0-400 ℃ and control the temperature with precision of ± (0.1-0.5) ° c.

In some embodiments of the present application, the spectrometer is further provided with a second flow rate controller 50 connected between the chromatographic column and the gas cell 20, for example, the second flow rate controller 50 may be a three-way valve for controlling the flow rate of the chromatographic fractions flowing out of the chromatographic column, so as to facilitate the terahertz module to obtain the sample terahertz signals of the respective chromatographic fractions.

After obtaining a plurality of chromatographic fractions through the gas chromatography module 10 shown in fig. 2, the plurality of chromatographic fractions may sequentially flow to the gas cell 20 through a conduit, and a terahertz light beam is generated by the terahertz module 30, and each chromatographic fraction in the gas cell 20 is irradiated to obtain a sample terahertz signal of each chromatographic fraction.

Specifically, as shown in fig. 2, the terahertz module 30 may include: a laser light source 301, a beam splitter 302, a terahertz radiation antenna 303 and a terahertz detection antenna 304.

Laser emitted by the laser light source 301 is split into pump light and probe light by the beam splitter 302; the detection light is emitted into the terahertz detection antenna 304; the terahertz radiation antenna 303 receives the pump light and generates a terahertz light beam; the terahertz light beam sequentially irradiates each chromatographic fraction in the gas cell to obtain sample light corresponding to each chromatographic fraction, and the sample light is emitted into the terahertz detection antenna 304; the terahertz detection antenna 304 receives the detection light and the sample light and generates a sample terahertz signal corresponding to each chromatographic fraction.

In the embodiment of the application, the terahertz module is used for generating the sample terahertz signal corresponding to each chromatographic fraction, so that each chromatographic fraction can be accurately identified.

In some embodiments of the present application, the gas cell 20 is provided with a terahertz light-transmitting window, a chromatographic fraction inlet conduit 201 and a chromatographic fraction outlet conduit 202. After the chromatographic fraction enters the gas cell 20 through the chromatographic fraction entering conduit 201, the terahertz light transmitting window piece enables a terahertz light beam generated by the terahertz module to be incident to the gas cell 20, and enables sample light generated by the terahertz module to be emitted to a terahertz detection antenna of the terahertz module; the chromatographic fraction then exits the gas cell 20 via the chromatographic fraction outlet conduit 202.

The terahertz transmission window sheet can be a TPX (poly (4-methylpentene)) window sheet.

In some embodiments of the present application, the gas cell may be a tubular gas cell with an inner wall plated with gold.

Because gold reflects the terahertz wave spectrum most strongly and the chemical inertia of gold can prevent the sample from being catalytically decomposed at high temperature, the tubular gas cell with the gold-plated inner wall can minimize the energy loss sum of the terahertz wave reflected by chromatographic fractions for multiple times in the tubular gas cell, thereby improving the sensitivity of the terahertz module.

In an embodiment of the application, after the sample terahertz signals corresponding to the chromatographic fractions are obtained, the signal processing module may receive the sample terahertz signals and process the sample terahertz signals to obtain a gas phase terahertz spectrogram of a sample to be measured.

The signal processing module 40 may collect the terahertz signals of the sample in a continuous collection manner, that is, process all the collected terahertz signals of the sample to obtain a gas-phase terahertz spectrogram of the sample to be detected; or setting a signal threshold value, and processing the sample terahertz signal with the signal intensity larger than the signal threshold value in the collected sample terahertz signals to obtain a gas phase terahertz spectrogram of the sample to be detected.

Due to the significant difference in chromatographic retention times (time sequence of separation) of compounds with different numbers of repeating units within the molecular structure, such as homologues, efficient separation can be performed by means of gas chromatography modules; in the identification of the compound or chiral drug containing the isomer and the polymorph, the difference in chromatographic retention time is small, but the terahertz spectrum has obvious difference, so that accurate identification can be performed through the terahertz module.

Specifically, in the embodiment of the application, after the sample terahertz signals of each chromatographic fraction are obtained, data points of terahertz absorption of a full waveband or a certain window in the data acquisition process can be integrated to obtain the gas phase terahertz spectrogram.

In order to further detect the sample to be detected (chromatographic fraction), in some embodiments of the present application, the gas chromatography module 10 may further include a gas detector 104 connected to the chromatographic fraction outflow conduit, and after the chromatographic fraction flows out of the gas cell 20 through the chromatographic fraction outflow conduit 202, the gas detector 104 may perform gas chromatography detection on the chromatographic fraction to obtain a gas chromatogram of the sample to be detected.

The gas phase detector may be a concentration-type detector or a mass-type detector, such as a Flame Ionization Detector (FID).

In some embodiments of the present application, the chromatography fraction outflow conduit 202 is further provided with a third flow rate controller 60 for adjusting the flow rate of the chromatography fraction flowing into the gas detector before the gas chromatography detection is performed by the gas detector.

Specifically, as shown in fig. 2, the carrier gas unit 101 provides a dry and pure carrier gas to convey the gaseous sample to be detected in the sample introduction unit 102 to the separation unit 103, so that the gaseous sample to be detected is separated by the separation unit 103 to obtain a plurality of chromatographic fractions. These chromatographic fractions are supplied to the gas cell 20 after the flow rate thereof is adjusted by the second flow rate controller 50. At this time, laser light emitted from the laser light source 301 is split into pump light and probe light by the beam splitter 302; the detection light is emitted into the terahertz detection antenna 304; the terahertz radiation antenna 303 receives the pump light and generates a terahertz light beam; the terahertz light beam sequentially irradiates each chromatographic fraction in the gas cell to obtain sample light corresponding to each chromatographic fraction, and the sample light is emitted into the terahertz detection antenna 304; the terahertz detection antenna 304 receives the detection light and the sample light and generates a sample terahertz signal corresponding to each chromatographic fraction. Then, the signal processing module 40 receives the sample terahertz signal and processes the sample terahertz signal to obtain a gas phase terahertz spectrogram of the sample to be detected. And the chromatographic fraction flowing out of the gas cell 20 flows into the gas phase detector 104 through the third flow rate controller 60, and the gas phase detector 104 collects the chromatographic fraction and obtains a gas chromatogram of the sample to be measured.

In the embodiments provided in the present application, it should be understood that the disclosed devices may also be implemented in other manners. For example, the terahertz spectrometers described above are merely illustrative; for another example, the division of each component is only one functional division, and there may be other division ways in actual implementation, for example, a plurality of components may be combined or may be integrated into another system, or some features may be omitted.

The above embodiments are only used to illustrate the technical solutions of the present application, and not to limit the same; although the present application has been described in detail with reference to the foregoing embodiments, it should be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; such modifications and substitutions do not substantially depart from the spirit and scope of the embodiments of the present application and are intended to be included within the scope of the present application.

Claims

1. A spectrometer, comprising: the device comprises a gas chromatography module, a gas pool, a terahertz module and a signal processing module;

the gas chromatography module is used for separating a sample to be detected to obtain a plurality of chromatographic fractions flowing to the gas pool in sequence;

the terahertz module is used for generating terahertz beams and irradiating each chromatographic fraction in the gas pool to obtain sample terahertz signals of each chromatographic fraction;

the signal processing module is connected with the terahertz module and used for receiving the sample terahertz signal and processing the sample terahertz signal to obtain a gas phase terahertz spectrogram of the sample to be detected.

2. The spectrometer of claim 1, wherein the gas chromatography module comprises: the device comprises a carrier gas unit, a sample introduction unit and a separation unit;

the carrier gas unit includes: the device comprises a gas source, a first flow rate controller and a purifying dryer; the carrier gas provided by the gas source is decompressed into carrier gas with set flow rate through the first flow rate controller, and the pure carrier gas is obtained under the action of the purification dryer;

the dry pure carrier gas is used for conveying the gaseous sample to be detected in the sample introduction unit to the separation unit and the gas cell;

the separation unit includes: a chromatographic column; and separating the gaseous sample to be detected by the chromatographic column to obtain a plurality of chromatographic fractions.

3. The spectrometer of claim 2, wherein the sample introduction unit comprises: the device comprises a vaporizing chamber and a heater, wherein the vaporizing chamber is used for vaporizing a liquid sample to be tested.

4. The spectrometer of claim 2, wherein the chromatography column is a capillary column.

5. A spectrometer as in claim 1, wherein the terahertz module comprises a laser light source, a beam splitter, a terahertz radiation antenna, and a terahertz detection antenna;

laser emitted by the laser light source is divided into pump light and probe light by the beam splitter;

the detection light is emitted into the terahertz detection antenna;

the terahertz radiation antenna receives the pump light and generates a terahertz light beam; the terahertz light beam sequentially irradiates each chromatographic fraction in the gas pool to obtain sample light corresponding to each chromatographic fraction, and the sample light is emitted into the terahertz detection antenna;

the terahertz detection antenna receives the detection light and the sample light and generates sample terahertz signals corresponding to the chromatographic fractions.

6. The spectrometer of claim 2, wherein the spectrometer is further provided with a second flow rate controller connected between the chromatographic column and the gas cell.

7. The spectrometer of claim 1, wherein the gas cell is provided with a terahertz transmission window, a chromatographic fraction inlet conduit and a chromatographic fraction outlet conduit;

the terahertz light-transmitting window sheet is used for enabling a terahertz light beam generated by the terahertz module to be incident to the gas pool and enabling sample light generated by the terahertz module to be emitted to a terahertz detection antenna of the terahertz module;

and the chromatographic fraction enters the gas pool through the chromatographic fraction inlet conduit and flows out of the gas pool through the chromatographic fraction outlet conduit.

8. The spectrometer of claim 7, wherein the gas chromatography module further comprises a gas detector connected to the chromatography fraction outflow conduit.

9. The spectrometer of claim 8, wherein the chromatography fraction outflow conduit is provided with a third flow rate controller.

10. The spectrometer of claim 7, wherein the gas cell is a tubular gas cell with gold plated inner walls.