Method for detecting sandalwood through surface enhanced Raman spectroscopy

Abstract

The invention relates to the technical field of detection, in particular to a method for detecting sandalwood through surface enhanced Raman spectroscopy, and solves the problem that existing sandalwood incense gas detection does not meet actual use requirements. The igniter is used for igniting to-be-detected sandalwood and continuously combusting to form to-be-detected gas; the sample cell is communicated with the combustion chamber and receives gas to be detected, and a surface enhancement structure is arranged in the sample cell; the laser is used for emitting laser into the sample cell to obtain the Raman spectrum; the analysis system is used for performing gas Raman signal analysis; an input end on-off valve and an output end on-off valve are respectively arranged at the gas inlet end and the gas outlet end of the sample pool.

Description

Technical Field

[0001] The invention relates to the field of detection technology, and in particular to a method for detecting sandalwood using surface enhanced Raman spectroscopy. Background Art

[0002] Burning incense is a habit that exists in ceremonies, folk customs and other scenes. Among them, sandalwood incense is the best incense for burning. The fragrance it emits when burning is elegant, calm and refreshing. Sandalwood incense, the specific products on the market refer to incense sandalwood products made by mixing natural sandalwood (powder or essential oil) as the main material with natural incense auxiliary materials. Its testing standards are based on the national standard QB / T 5254-2018 Natural Plant Material Incense-Sandalwood, GB 26386 General Technical Conditions for Safety of Incense Products, GB / T 26393 Testing Methods for Hazardous Substances in Incense Products and QB / T 1692.4 Hygienic Incense.

[0003] In the prior art, a Chinese patent with publication number CN 217277883 U proposes a gas rapid detector based on the principle of Raman spectroscopy, including an upper cover and a cavity, wherein the upper cover is hinged to one end of the upper surface of the cavity, and the upper surface of the cavity is provided with an air inlet and an air outlet; a non-concentric cavity reflection module and a spectrometer detection module are provided in the cavity, and an air cavity for storing the gas to be tested and a Raman spectrum excitation enhancement module for enhancing the Raman signal are provided inside the non-concentric cavity reflection module; the air cavity is connected to the air inlet and the air outlet through pipelines, and electromagnetic valves are provided on the pipeline between the air inlet and the air cavity and on the pipeline between the air outlet and the air cavity. Through this instrument, common oxygen, nitrogen, carbon dioxide, ethanol, etc. can be simply and quickly detected, and nitrogen-containing gases, olefin gases, and toxic gases that are easy to cause environmental and atmospheric pollution can also be quickly detected.

[0004] But in fact, when burning incense, it has different states depending on the user's environment and scenario. When detecting, it is necessary to consider various gases in different concentrations and fluid states. The current detection method obviously cannot take this into account. Summary of the invention

[0005] Therefore, the present invention provides a method for detecting sandalwood by surface enhanced Raman spectroscopy, which solves the problem that the existing sandalwood incense gas detection does not meet the actual use requirements.

[0006] To achieve the above object, the present invention is achieved through the following technical solutions:

[0007] A method for detecting sandalwood using surface enhanced Raman spectroscopy, using a detection device for detection, the detection device comprising:

[0008] The combustion chamber is used to ignite the sandalwood to be tested and continuously burn it to form the gas to be tested;

[0009] A sample pool is connected to the combustion chamber and receives the gas to be tested, and a surface enhancement structure is arranged in the sample pool;

[0010] A laser, used for emitting laser light into the sample cell to obtain the Raman spectrum;

[0011] An analysis system for analyzing gas Raman signals;

[0012] The air inlet and outlet ends of the sample pool are respectively provided with an input opening and closing valve and an output opening and closing valve;

[0013] The detection process includes the following steps:

[0014] S1. Flow dynamic gas sampling detection:

[0015] S11, opening the input end opening and closing valve and the output end opening and closing valve, so that the gas to be tested in the combustion chamber enters the sample pool and is continuously output from the gas outlet;

[0016] S12, after the airflow at the air outlet is stable, the laser emits laser light and focuses it at the surface enhancement structure to obtain a Raman spectrum;

[0017] S13, the analysis system performs flow dynamic gas analysis to obtain a detection result R1;

[0018] S2. Closed gas sampling and testing:

[0019] S21, opening the on-off valve at the input end and closing the on-off valve at the output end, so that the gas to be tested in the combustion chamber enters the sample pool and is continuously input;

[0020] S22, after the sample pool has the gas to be tested, set a fixed interval time T 1 , the laser emits laser light and focuses it at the surface enhancement structure to obtain Raman spectrum, and the analysis system sequentially performs gas analysis to obtain detection results RT1, RT2, ..., RTN;

[0021] S23, drawing a spectrum change curve diagram for the obtained spectrum line;

[0022] S3. Exhaust gas sampling and testing:

[0023] S31, open the input end opening and closing valve, close the output end opening and closing valve, so that the gas to be tested in the combustion chamber enters the sample pool and continues to be input, and after the gas pressure in the sample pool is stable, close the input end opening and closing valve, and open the output end opening and closing valve to allow the gas to be exhausted naturally;

[0024] S32, set a fixed interval time T 2, the laser emits laser light and focuses it at the surface enhancement structure to obtain Raman spectrum, and the analysis system sequentially performs gas analysis to obtain detection results RT11, RT12...RT1 N;

[0025] S33, drawing a spectrum change curve diagram for the obtained spectrum line;

[0026] S4. Obtain data according to the above steps S1, S2, and S3 for manual analysis.

[0027] Preferably, the sample cell comprises a cavity and an incident window arranged on the cavity for laser to enter the sample cell.

[0028] Preferably, the cavity is a variable volume structure.

[0029] Preferably, the sample cell further comprises a reflective window and a reflector thereof which are arranged opposite to the incident window.

[0030] Preferably, the surface enhancement structure is composed of quartz and a porous material grown on the surface of quartz.

[0031] Preferably, the analysis system includes a spectrometer for analysis, a collection lens for collecting scattered light, a filter, a coupling lens, and a concave reflector.

[0032] Preferably, the spectrometer is a CCD direct-reading spectrometer.

[0033] Preferably, the laser is an integrated transceiver laser.

[0034] By adopting the above technical solution, the beneficial effects of the present invention are:

[0035] This technical solution is aimed at daily use scenarios. In principle, it adopts the currently advanced surface enhanced Raman spectroscopy detection method for detection, and designs detection processes under different states. According to different scenarios, the first flow state indicates that the air flow in the scene is stable, the second closed state indicates that the air in the scene is not circulating and the air pressure continues to change, and the third exhaust state indicates the continuous gas dispersion state after combustion is completed. These different scenarios are analyzed separately to obtain more complete and comprehensive analysis and detection results. From the results, we can know the gas state changes, change rate and composition changes during the combustion of the test sample. The test results are more in line with the basic needs of the product in actual use scenarios, and are more convenient for customizing the classification and quality grade division of sandalwood incense products, setting a more detailed, accurate and practical technical specification standard. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 It is a schematic diagram of the structure of the detection device according to an embodiment of the present invention.

[0037] Figure numerals: 1. combustion chamber; 2. sample pool; 2a. air inlet; 2b. air outlet; 21. input opening and closing valve; 22. output opening and closing valve; 23. incident window; 24. reflection window; 25. reflector; 3. laser; 4. analysis system; 41. spectrometer; 42. collecting lens; 43. filter; 44. coupling lens; 5. surface enhancement structure. DETAILED DESCRIPTION

[0038] The following will describe the implementation methods of the present invention in detail in conjunction with specific embodiments, so that the implementation process of how the present invention applies technical means to solve technical problems and achieve technical effects can be fully understood and implemented accordingly.

[0039] Example

[0040] A method for detecting sandalwood by surface enhanced Raman spectroscopy, using a detection device for detection, referring to Figure 1 , the detection equipment comprises:

[0041] Combustion chamber 1, used for igniting the sandalwood to be tested and continuously burning it to form the gas to be tested;

[0042] The sample pool 2 is connected to the combustion chamber 1 and receives the gas to be tested. A surface enhancement structure 5 is arranged in the sample pool 2. The surface enhancement structure 5 is composed of quartz and a porous material grown on the surface of quartz. The porous material has a large surface area, high porosity, high transmittance to visible light, and a high laser damage threshold, and also has good gas adsorption and capture effects.

[0043] A laser 3, used for emitting laser light into the sample pool 2 to obtain the Raman spectrum;

[0044] The analysis system 4 is used for gas Raman signal analysis; the analysis system 4 includes a spectrometer 41 for analysis, a collection lens 42 for collecting scattered light, a filter 43, and a coupling lens 44, wherein the spectrometer 41 is a CCD direct reading spectrometer 41, which is convenient for directly reading relevant parameters. For details, please refer to the content of the prior art document CN 113218930 A.

[0045] The air inlet end 2a and the air outlet end 2b of the sample pool 2 are respectively provided with an input end opening and closing valve 21 and an output end opening and closing valve 22;

[0046] The detection process includes the following steps:

[0047] S1. Flow dynamic gas sampling detection:

[0048] S11, opening the input end opening and closing valve 21 and the output end opening and closing valve 22, so that the gas to be tested in the combustion chamber 1 enters the sample pool 2 and is continuously output from the gas outlet 2b;

[0049] S12, after the airflow at the air outlet 2b is stable, the laser 3 emits laser light and focuses it at the surface enhancement structure 5 to obtain a Raman spectrum;

[0050] S13, the analysis system 4 performs flow dynamic gas analysis to obtain a detection result R1;

[0051] Specifically, R1 is a spectral structure under a stable gas flow state, which can represent the basic quality of the test sample and detect whether polluted gas is generated and the content of related gases.

[0052] S2. Closed gas sampling and testing:

[0053] S21, opening the input-end on-off valve 21 and closing the output-end on-off valve 22, so that the gas to be tested in the combustion chamber 1 enters the sample pool 2 and is continuously input;

[0054] S22, after the sample pool 2 has the gas to be tested, a fixed interval time T1 is set, the laser 3 emits laser light and focuses it on the surface enhancement structure 5 to obtain a Raman spectrum, and the analysis system 4 performs gas analysis in sequence to obtain detection results RT1, RT2, ..., RTN;

[0055] S23, draw a spectrum change curve for the obtained spectrum line; when the spectrum of RTN and RT(N-1) does not change much, the process can be terminated.

[0056] Among them, this spectral change curve can represent the internal composition and cost change status of the gas of the sample to be tested during the entire combustion process and after the gas concentration changes. After multiple samples are tested separately, the differences between different samples can be obtained more intuitively.

[0057] S3. Exhaust gas sampling and testing:

[0058] S31, open the input end opening and closing valve 21, close the output end opening and closing valve 22, so that the gas to be tested in the combustion chamber 1 enters the sample pool 2 and continues to be input, and after the gas pressure in the sample pool 2 is stable, close the input end opening and closing valve 21, and open the output end opening and closing valve 22 to allow the gas to be exhausted naturally;

[0059] S32, set a fixed interval time T2, the laser 3 emits laser light and focuses it on the surface enhancement structure 5 to obtain Raman spectrum, and the analysis system 4 performs gas analysis in sequence to obtain detection results RT11, RT12...RT1N; similarly, when the spectrum of RT1N and RT1(N-1) does not change much, the process can be terminated.

[0060] S33, drawing a spectrum change curve diagram for the obtained spectrum line;

[0061] S4. Obtain data according to the above steps S1, S2, and S3 for manual analysis. This technical solution is aimed at daily use scenarios. In principle, it adopts the currently advanced surface enhanced Raman spectroscopy detection method for detection. The detection process under different states is designed. According to different scenes, the first flow state indicates that the air flow in the scene is stable, the second closed state indicates that the air in the scene is not circulating and the air pressure continues to change, and the third exhaust state indicates the continuous gas dispersion state after the combustion is completed; these different scenes are analyzed separately to obtain more complete and comprehensive analysis and detection results. From the results, we can know the gas state changes, change rate and composition changes during the combustion of the test sample. The test results are more in line with the basic needs of the actual use scenario for the product, and are more convenient for customizing the classification and quality grade classification of sandalwood incense products, setting a more detailed, accurate and practical technical specification standard.

[0062] Structurally, the sample pool 2 includes a cavity and an incident window 23 disposed on the cavity for the laser to enter the sample pool 2. The incident window 23 is a window coated with a visible light anti-reflection film, which can ensure the stable output of the laser; wherein, the cavity is a variable volume structure, and the variable volume structure is a foldable organ pipe structure; and this design is used in different sample detection (combustion gas volume, sample size and other factors), so that the equipment can meet the detection needs, and at the same time, the cavity size can be adjusted when necessary to obtain the required gas concentration inside the sample pool 2 more quickly.

[0063] In the actual detection process, in order to improve the identifiability of the analysis, a reflective window 24 and a reflector 25 disposed opposite to the incident window 23 can be provided in the sample pool 2. This structure can achieve another light collection by reflecting the laser, further enhancing the full scattering signal. In this structure, the laser 3 is an integrated transceiver laser 3.

[0064] Although the present invention has been specifically shown and described in conjunction with the preferred embodiments, it should be understood by those skilled in the art that various changes may be made to the present invention in form and details without departing from the spirit and scope of the present invention as defined by the appended claims, all of which are within the scope of protection of the present invention.

Claims

1. A method for detecting sandalwood using surface enhanced Raman spectroscopy, characterized in that: A detection device is used for detection, and the detection device comprises: A combustion chamber (1), used for igniting the sandalwood to be tested and continuously burning it to form a gas to be tested; A sample pool (2) is connected to the combustion chamber (1) and receives the gas to be tested, and a surface enhancement structure (5) is arranged in the sample pool (2); A laser (3) for emitting laser light into the sample pool (2) to obtain the Raman spectrum; An analysis system (4), used for analyzing gas Raman signals; The air inlet end (2a) and the air outlet end (2b) of the sample pool (2) are respectively provided with an input end opening and closing valve (21) and an output end opening and closing valve (22); The detection process includes the following steps: S1. Flow dynamic gas sampling detection: S11, opening the input end opening and closing valve (21) and the output end opening and closing valve (22), so that the gas to be tested in the combustion chamber (1) enters the sample pool (2) and is continuously output from the gas outlet (2b); S12, after the airflow at the air outlet (2b) is stabilized, the laser (3) emits laser light and focuses it at the surface enhancement structure (5) to obtain a Raman spectrum; S13, the analysis system (4) performs flow dynamic gas analysis to obtain a detection result R1; S2. Closed gas sampling and testing: S21, opening the input end on-off valve (21) and closing the output end on-off valve (22), so that the gas to be tested in the combustion chamber (1) enters the sample pool (2) and continues to be input; S22, after the sample pool (2) contains the gas to be tested, a fixed interval time T1 is set, the laser (3) emits laser light and focuses it at the surface enhancement structure (5) to obtain a Raman spectrum, and the analysis system (4) sequentially performs gas analysis to obtain detection results RT1, RT2, ..., RTN; S23, drawing a spectrum change curve diagram for the obtained spectrum line; S3. Exhaust gas sampling and testing: S31, opening the input end opening and closing valve (21) and closing the output end opening and closing valve (22), so that the gas to be tested in the combustion chamber (1) enters the sample pool (2) and is continuously inputted, and after the gas pressure in the sample pool (2) is stabilized, closing the input end opening and closing valve (21) and opening the output end opening and closing valve (22) to allow the gas to be exhausted naturally; S32, setting a fixed interval time T2, the laser (3) emits laser light and focuses it on the surface enhancement structure (5) to obtain a Raman spectrum, and the analysis system (4) performs gas analysis in sequence to obtain detection results RT11, RT12 ... RT1 N; S33, drawing a spectrum change curve diagram for the obtained spectrum line; S4. Obtain data according to the above steps S1, S2, and S3 for manual analysis.

2. The method for detecting sandalwood by surface enhanced Raman spectroscopy according to claim 1, characterized in that: The sample pool (2) comprises a cavity and an incident window (23) arranged on the cavity and used for laser light to enter the sample pool (2).

3. The method for detecting sandalwood by surface enhanced Raman spectroscopy according to claim 2, characterized in that: The cavity is a variable volume structure.

4. The method for detecting sandalwood by surface enhanced Raman spectroscopy according to claim 2, characterized in that: The sample pool (2) also includes a reflection window (24) and a reflection mirror (25) disposed opposite to the incident window (23).

5. A method for detecting sandalwood by surface enhanced Raman spectroscopy according to any one of claims 1 to 4, characterized in that: The surface enhancement structure (5) is composed of quartz and porous material grown on the surface of quartz.

6. A method for detecting sandalwood by surface enhanced Raman spectroscopy according to any one of claims 1 to 4, characterized in that: The analysis system (4) comprises a spectrometer (41) for analysis, a collection lens (42) for collecting scattered light, a filter (43), a coupling lens (44), and a concave reflection mirror (25).

7. The method for detecting sandalwood by surface enhanced Raman spectroscopy according to claim 6, characterized in that: The spectrometer (41) is a CCD direct-reading spectrometer (41).

8. A method for detecting sandalwood by surface enhanced Raman spectroscopy according to any one of claims 1 to 4, characterized in that: The laser (3) is an integrated transceiver laser (3).

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