A Raman spectroscopy analysis system and method for the moisture binding strength and content of particles

Abstract

The present invention discloses a Raman spectroscopy analysis system and method for the binding strength and content of particulate moisture. The system includes: a laser generation module for generating a laser; a surface light source optical path for adjusting the laser to form a surface light source and guiding the surface light source rays to the area of the sample to be detected; a point light source optical path for adjusting the laser to form a point light source and guiding the point light source rays to the area of the sample to be detected; a mobile scanning detection component for placing the sample to be detected and adjusting the detected position of the sample to be detected; a Raman spectroscopy component for receiving the Raman signals excited by the surface light source and the point light source and performing a combined analysis of the field signal and the point signal to obtain the surface moisture binding degree and distribution of the sample to be detected. The system and method provided by the present invention can realize the detection and analysis of the binding state and content of particulate moisture molecules.

Description

Technical Field

[0001] The present invention relates to the field of testing the physical and chemical properties of particulate media, and particularly to a Raman spectroscopy analysis system and method for the binding strength and content of particulate moisture. Background Art

[0002] In many discrete medium systems, the complex interaction between particles and water often makes the physical and chemical properties of substances exhibit uniqueness. Taking natural soil as an example, according to the forms of existence, states, activities of water and its interaction with soil, the water in soil can be divided into different types such as mineral component water, bound water, liquid water, gaseous water, solid water, etc., and their respective contents are the main factors determining the properties of water.

[0003] In the development and application of particulate related engineering technologies, obtaining information on the moisture binding state and moisture content in particulate media is of great significance for predicting the macroscopic properties of the media, designing parameters of related technological processes, etc. At the micro-nano scale of the particle surface interface, obtaining the distribution of various types of moisture on the surface of particles plays an important supporting role in the research and development of particle technology, revealing the microscopic mechanism, and actively regulating and designing particle behavior.

[0004] At present, the detection of different types of water on the particle surface at home and abroad is mainly achieved indirectly based on differences in boiling points, freezing points and salt contents of different types of moisture. Usually, only the contents of some moisture can be obtained, and the accuracy of the test results depends on the precision of experimental test means. There is a lack of rapid, accurate and comprehensive analysis methods and equipment for the moisture binding state and distribution on the particle surface.

[0005] Spectral technology is the most effective experimental method for studying the occurrence forms of water molecules. It can judge the differences in the binding forms of water and solids by distinguishing the vibration frequencies of water molecules or the radial distribution differences of oxygen and hydrogen atoms. Combining spectral analysis means, the binding types of moisture can be effectively classified and quantitatively distinguished, so as to accurately obtain the moisture binding state and content of particles. Therefore, the research on rapid, accurate and comprehensive detection and analysis technology for the moisture binding degree and distribution on the particle surface plays an important supporting role in the development of current cutting-edge particle technologies.

[0006] In view of the above disadvantages, the present invention urgently needs to provide a Raman spectroscopy analysis system and method for the binding strength and content of particulate moisture to solve technical problems such as the difficulty of quickly, accurately and conveniently testing the binding strength and content of particulate surface moisture by traditional particulate moisture detection methods. Summary of the Invention

[0007] The technical problem to be solved by the present invention is to provide a Raman spectroscopy analysis system and method for the binding strength and content of particulate moisture in view of the defects in the prior art.

[0008] The technical solution adopted by the present invention to solve its technical problems is as follows:

[0009] The present invention provides a Raman spectroscopy analysis system for the moisture binding strength and content of particles, and the system includes:

[0010] A laser generation module for generating a laser;

[0011] A surface light source optical path for adjusting the laser to form a surface light source and guiding the surface light source light to the area of the sample to be detected;

[0012] A point light source optical path for adjusting the laser to form a point light source and guiding the point light source light to the area of the sample to be detected;

[0013] A mobile scanning detection component for placing the sample to be detected and adjusting the position of the sample to be detected for detection;

[0014] A Raman spectroscopy component for receiving the Raman signals excited by the surface light source and the point light source, and performing a joint analysis of the field signal and the point signal to obtain the moisture binding degree and distribution on the surface of the sample to be detected.

[0015] Further, the Raman spectroscopy component of the present invention includes:

[0016] A field information receiving channel for receiving the Raman signals excited by the surface light source;

[0017] A point information receiving channel for receiving the Raman signals excited by the point light source;

[0018] A Raman spectrometer connected to the output ends of the field information receiving channel and the point information receiving channel for converting the Raman signals excited by the surface light source and the point light source into electrical signals;

[0019] A field-point information joint analysis module connected to the output end of the Raman spectrometer for generating the Raman spectrum of the sample to be detected according to the electrical signals and obtaining the moisture binding degree and distribution on the surface of the sample to be detected;

[0020] A control module connected to both the field-point information joint analysis module and the mobile scanning detection component for controlling the mobile scanning detection component.

[0021] Further, the mobile scanning detection component of the present invention includes:

[0022] A three-dimensional motion control console for changing the position of the detection sample in three-dimensional space;

[0023] The detection focus control optical control module is connected to both the field information receiving channel and the point information receiving channel, and is used to adjust the position of the focal plane or the focus in three-dimensional space.

[0024] Further, the implementation manners of the surface light source optical path and the point light source optical path of the present invention include:

[0025] Two optical paths with independent spatial positions;

[0026] Or, a switchable optical path constructed by installing light-transmitting members with different apertures on a common optical path.

[0027] Further, the implementation manners of the field signal receiving channel and the point signal receiving optical path of the present invention include:

[0028] A signal transmission channel with an independent spatial position;

[0029] Or, a switchable signal transmission channel constructed by installing a pinhole light-transmitting structure on the imaging plane of a common signal transmission channel.

[0030] Further, the sample to be detected in the present invention is water-containing particles including rock and soil particles, sludge particles, etc.

[0031] The present invention provides a Raman spectroscopy analysis method for the moisture binding strength and content of particles. Using the Raman spectroscopy analysis system for the moisture binding strength and content of particles, the method includes the following steps:

[0032] Step 1: Set the sample to be detected on a three-dimensional motion control table, and the laser generation module emits laser light;

[0033] Step 2: The point light source optical path adjusts the laser light to form a point light source, and guides the point light source light to the area of the sample to be detected. The detection focus optical control module focuses the point light source light on the surface of the sample to be detected. The point information receiving channel receives the Raman signal excited by the point light source, and the Raman spectrometer converts the Raman signal into an electrical signal; by adjusting the focus position and the three-dimensional motion control table, make the focus position P x,y,z Move in the z-axis direction to obtain different Raman spectral signals; extract the peak frequencies f of each measurement point through the field-point information joint analysis module z And arrange them in the order of the z coordinates, and take the frequency values f with the adjacent frequency differences greater than the threshold N i To form a basis vector t, and the different frequency values f of the basis vector i Represent different types of moisture-binding water;

[0034] Step 3: The surface light source optical path adjusts the laser to form a surface light source, guides the surface light source light to the area of the sample to be detected, the detection focus optical control module focuses the surface light source light on the surface of the sample to be detected, the field information receiving channel receives the Raman signal excited by the surface light source, and the Raman spectrometer converts the Raman signal into an electrical signal; the field-point information joint analysis module decomposes the Raman spectrum according to the characteristic frequency value f in the basis vector t i and performs curve fitting using a Gaussian function to obtain the content of each type of water in combination;

[0035] Step 4: According to the characteristic frequency peak f i and the Gaussian decomposition peak area A of different characteristic frequency peaks f i calculate the weighted peak frequency of the field average spectrum, and then define the average degree of water consolidation χ i representing the average binding strength between water and solid, substitute the characteristic peak frequencies f w to obtain the degree of consolidation of the corresponding water type. i

[0036] Furthermore, in the method of the present invention, the method for obtaining the content of each type of water in combination is specifically as follows:

[0037] Decompose the Raman spectrum according to the characteristic frequency value f in the basis vector t i and perform curve fitting using a Gaussian function:

[0038] ∫ L H fdx = ∑f i ·A i

[0039] where A i is the Gaussian decomposition peak area of different characteristic frequency peaks f i , and the content x of each type of water in combination i is expressed as:

[0040]

[0041] Furthermore, in the method of the present invention, the specific method for the degree of consolidation of the corresponding water type is as follows:

[0042] Calculate the weighted peak frequency F of the field average spectrum w :

[0043]

[0044] Define the average degree of water consolidation χ w representing the average binding strength between water and solid:

[0045] ​

[0046] In the formula, F WS represents the characteristic peak frequency of ice. For solid water such as ice, the water binding degree is 1; f 0 represents the characteristic peak frequency corresponding to free water when the binding strength between water and solid is the lowest, which is usually the peak frequency f WS farthest from F i on one side among the measured Raman signals, which is the extreme value.

[0047] Calculate the consolidation degree of the water type corresponding to each characteristic peak frequency f i :

[0048]

[0049] For the water with a larger χ i , the consolidation degree is higher.

[0050] Furthermore, in the method of the present invention, the point-source Raman spectral signal reflecting the binding degree between water molecules and solid particles is obtained from the point-source light path, and the peak frequency information of water molecules reflecting the binding degree between water molecules and solid particles is extracted. The information on the binding state between water molecules and solid is included in the peak frequency of the spectrum; the field-source Raman spectral signal reflecting the binding degree between water molecules and solid particles is obtained from the field-source light path, and the water content of different types is inversely obtained from the field Raman spectral signal.

[0051] The beneficial effects produced by the present invention are as follows:

[0052] 1. The present invention provides a Raman spectral analysis system and method for the binding strength and content of particulate water, which solves the technical problems such as the difficulty in quickly, accurately, and conveniently testing the binding strength and content of surface water of particles in traditional particulate water detection methods.

[0053] 2. The system of the present invention adopts a two-way design of a point-source light path and a surface-source light path, which can obtain the point-source Raman spectral signal and the surface-source Raman spectral signal. Through signal processing of them, a more comprehensive analysis result of the binding strength and content of particulate water can be obtained; the position of the sample to be detected is accurately controlled through a three-dimensional motion control console, and multi-group experimental data can be collected; through the detection footpad optical control module, the focal points of the two lasers of the point-source and the surface-source can be accurately adjusted.

[0054] 3. The present invention provides a Raman spectral detection and analysis method for the distribution of particulate water, which can realize the detection and analysis of the binding state and content of particulate water molecules.

[0055] 4. In the method of the present invention, by distinguishing the vibration frequency of water molecules or the difference in the radial distribution of oxygen and hydrogen atoms, the difference in the binding form between water and solid is judged. Combining with spectral analysis means, the water binding types can be effectively classified and quantitatively distinguished.

[0056] 5. In the method of the present invention, a dual - optical - path Raman system with a surface light source and a point light source is used to realize the classification of the types of moisture on the particle surface and the quantitative analysis of the proportion of each type of moisture. BRIEF DESCRIPTION OF THE DRAWINGS

[0057] The present invention will be further described below in conjunction with the drawings and embodiments. In the drawings:

[0058] Figure 1 is the schematic diagram of the Raman spectroscopy analysis system and method for the particle moisture binding strength and content of the present invention;

[0059] Figure 2 is the implementation scheme diagram of the Raman spectroscopy analysis system and method for the particle moisture binding strength and content of the present invention involved in the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0060] In order to make the objectives, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below in conjunction with the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0061] Embodiment 1

[0062] The embodiment of the present invention provides a Raman spectroscopy analysis system and method for particle moisture binding strength and content, and its design principle is as follows:

[0063] The information on the binding state of water molecules to solids is contained in the peak frequency of the spectrum: on the particle surface, water molecules are restricted by the particles, inhibiting the symmetric stretching of the OH bond of water molecules, resulting in a "red - shift frequency". Therefore, a higher peak frequency corresponds to higher - frequency vibrating water molecules, and water molecules more tightly bound to the solid will exhibit a lower spectral peak frequency.

[0064] The OH vibration frequency of water molecules is not only related to the hydrogen - bond state formed by this water molecule, but also related to the hydrogen - bond state of other water molecules around this water molecule. The field - averaged spectral peak frequency is the result of the superposition of all vibration frequencies of the OH bond. The width of the Raman spectrum reflects the diversity of the OH vibration forms of water molecules. The wider the spectrum, the more types of water molecules.

[0065] By distinguishing the differences in the vibration frequency of water molecules or the radial distribution differences of oxygen and hydrogen atoms to judge the differences in the binding forms of water and solids, combined with spectral analysis means, the types of water binding can be effectively classified and quantitatively distinguished, so as to accurately obtain the particle water binding state and content, and a Raman spectroscopy analysis system and method for particle moisture binding strength and content are given.

[0066] Embodiment 2

[0067] Based on the design principle of Embodiment 1, an embodiment of the present invention provides a Raman spectroscopy analysis system for the binding strength and content of particulate moisture, as follows Figure 1 shown, the system includes:

[0068] A laser generation module 33 for generating a laser;

[0069] A surface light source optical path 31 for adjusting the laser to form a surface light source and guiding the surface light source rays to the area of the sample to be detected;

[0070] A point light source optical path 32 for adjusting the laser to form a point light source and guiding the point light source rays to the area of the sample to be detected;

[0071] A mobile scanning detection component 2 for adjusting the detected position of the sample to be detected 22;

[0072] A Raman spectroscopy component 1 for receiving the Raman signals excited by the surface light source and the point light source, and performing a joint analysis of the field signal and the point signal to obtain the moisture binding degree and distribution on the surface of the sample to be detected.

[0073] A field information receiving channel 14 for receiving the Raman signals excited by the surface light source;

[0074] A point information receiving channel 15 for receiving the Raman signals excited by the point light source;

[0075] A Raman spectrometer 13 for converting the Raman signals into electrical signals;

[0076] A field-point information joint analysis module 12 for generating a Raman spectrum of the sample to be detected 22 based on the electrical signals and obtaining the moisture binding degree and distribution on the surface of the sample to be detected;

[0077] A control module 11 for controlling the mobile scanning detection component 2.

[0078] A three-dimensional motion control console 21 for changing the position of the detection sample 22 in three-dimensional space;

[0079] A detection focus control optical control module 23 for adjusting the position of the focal plane or the focus in three-dimensional space.

[0080] In a preferred embodiment of the present invention, the surface light source optical path 31 and the point light source optical path 32 can be two optical paths with independent spatial positions, or can be a switchable optical path constructed by installing different aperture light-transmitting components on a common optical path.

[0081] In a preferred embodiment of the present invention, the field signal receiving channel 14 and the point signal receiving optical path 15 can be signal transmission channels with independent spatial positions, or can be switchable signal transmission channels constructed by adding a pinhole light-transmitting structure to the imaging plane of a common signal transmission channel.

[0082] In a preferred embodiment of the present invention, in the Raman spectroscopy detection and analysis system for the particle moisture distribution, the sample to be detected 22 that can be detected can be rock and soil particles, sludge particles, and other water-containing particles;

[0083] Embodiment 3

[0084] Based on the design principle of Embodiment 1 and the system of Embodiment 2, the present invention provides a method for Raman spectroscopy detection and analysis of particle moisture distribution, and the method includes the following steps:

[0085] Step 1: The laser generation module 33 generates a laser.

[0086] Step 2: The point light source optical path 32 adjusts the laser to form a point light source, and guides the point light source light to the area of the sample to be detected. The detection focus optical control module 23 focuses the point light source light on the surface of the sample to be detected 22. The point information receiving channel 15 receives the Raman signal excited by the point light source, and the Raman spectrometer 13 converts the Raman signal into an electrical signal. By adjusting the focus position and the three-dimensional motion control table 21, the focus position P x,y,z moves in the z-axis direction to obtain different Raman spectroscopy signals, extracts the peak frequencies f of each measurement point z and arranges them in the order of the z coordinates, and takes the frequency values f with the adjacent frequency differences greater than the threshold N i to form a basis vector t. The different frequency values f of the basis vector i represent different bound water types.

[0087] Step 3: The surface light source optical path 31 adjusts the laser to form a surface light source, and guides the surface light source light to the area of the sample to be detected. The detection focus optical control module 23 focuses the surface light source light on the surface of the sample to be detected 22. The field information receiving channel 14 receives the Raman signal excited by the surface light source, and the Raman spectrometer 13 converts the Raman signal into an electrical signal. Decompose the Raman spectroscopy with the characteristic frequency values f in the basis vector t i and perform curve fitting using a Gaussian function:

[0088] ∫ L H fdx = ∑f i ·A i

[0089] In the formula, A i is the peak of different characteristic frequencies f iThe peak area of Gaussian decomposition. Calculate the content x of water with different binding types i is as follows:

[0090]

[0091] Calculate the field-averaged spectral weighted peak frequency F w :

[0092]

[0093] Define the average degree of water consolidation χ w which represents the average binding strength of water to the solid:

[0094]

[0095] In the formula, F WS represents the characteristic peak frequency of ice. For solid water such as ice, the degree of water binding is 1; f 0 represents the characteristic peak frequency corresponding to free water when the binding strength between water and the solid is the lowest, usually the peak frequency f WS on the side farthest from F i in the measured Raman signal. Calculate the degree of consolidation of each characteristic peak frequency f i corresponding to the water type:

[0096]

[0097] For χ i the greater the water content, the higher the degree of consolidation.

[0098] In summary, the present invention determines the difference in the binding form of water to the solid by distinguishing the vibration frequency of water molecules or the difference in the radial distribution of oxygen and hydrogen atoms. Combining spectral analysis means, the binding types of water can be effectively classified and quantitatively distinguished;

[0099] The present invention uses a double-light-path Raman system with a surface light source and a point light source to realize the classification of water types on the particle surface and the quantitative analysis of the proportion of each type of water.

[0100] It should be understood that the magnitudes of the sequence numbers of the steps in the above embodiments do not mean the order of execution. The order of execution of each process should be determined by its function and internal logic, and should not constitute any limitation to the implementation process of the embodiments of the present application.

[0101] It should be understood that those of ordinary skill in the art can make improvements or changes according to the above description, and all such improvements and changes should fall within the protection scope of the appended claims of the present invention.

Claims

1. A Raman spectroscopy analysis system for particle water binding strength and content, characterized in that: The system includes: A laser generating module (33), used for generating laser light; A surface light source optical path (31), used for adjusting the laser to form a surface light source, and guiding the light of the surface light source to a sample area to be detected; A point light source optical path (32), used to adjust the laser to form a point light source, and guide the light of the point light source to a sample area to be detected; A mobile scanning detection component (2) is used to place a sample to be detected (22) and adjust the detected position of the sample to be detected (22); A Raman spectroscopy component (1) is used to receive the Raman signals excited by the surface light source and the point light source, and to perform a joint analysis of the field signal and the point signal to obtain the degree and distribution of water binding on the surface of the sample to be detected (22); The Raman spectroscopy component (1) comprises: A field information receiving channel (14), used for receiving the Raman signal excited by the surface light source; A point information receiving channel (15), used for receiving a Raman signal excited by the point light source; A Raman spectrometer (13), connected to the output ends of the field information receiving channel (14) and the point information receiving channel (15), and used for converting the Raman signal excited by the surface light source and the Raman signal excited by the point light source into an electrical signal; A field-point information joint analysis module (12) is connected to the output end of the Raman spectrometer (13) and is used to generate a Raman spectrum of the sample to be detected (22) according to the electrical signal to obtain the degree of water binding and distribution on the surface of the sample to be detected (22); and extract the peak frequency of each measurement point through the field-point information joint analysis module (12). and press z The coordinates are arranged in order, and the adjacent frequency difference is greater than the threshold N The characteristic frequency value of Forming basis vectors , different eigenfrequency values ​​of the basis vectors Represents different types of water; the Raman spectrum is analyzed by the field-point information joint analysis module (12) with basis vectors The characteristic frequency value in Decompose and use Gaussian function to fit the curve, and then get the water content of each combination type; A control module (11) is connected to the field-point information joint analysis module (12) and the mobile scanning detection component (2), and is used to control the mobile scanning detection component (2).

2. The Raman spectroscopy analysis system for particle water binding strength and content according to claim 1, characterized in that: The mobile scanning and detection component (2) comprises: A three-dimensional motion control console (21) for changing the position of the detection sample (22) in three-dimensional space; The focus detection control optical control module (23) is connected to both the field information receiving channel (14) and the point information receiving channel (15), and is used to adjust the position of the focal plane or focus in three-dimensional space.

3. The Raman spectroscopy analysis system for particle water binding strength and content according to claim 1, characterized in that: The implementation method of the surface light source optical path (31) and the point light source optical path (32) includes: Two optical paths with independent spatial positions; Alternatively, a switchable optical path can be constructed by adding light-transmitting components with different apertures to a common optical path.

4. The Raman spectroscopy analysis system for particle water binding strength and content according to claim 1, characterized in that: The implementation method of the field signal receiving channel (14) and the point signal receiving optical path (15) includes: Signal transmission channels with independent spatial locations; Alternatively, a switchable signal transmission channel is constructed by adding a pinhole light-transmitting structure to the imaging plane of the common signal transmission channel.

5. The Raman spectroscopy analysis system for particle water binding strength and content according to claim 1, characterized in that: The samples to be tested (22) are water-containing particles including rock particles and sludge particles.

6. A Raman spectroscopy analysis method for particle moisture binding strength and content, using the Raman spectroscopy analysis system for particle moisture binding strength and content according to any one of claims 1 to 5, characterized in that: The method comprises the following steps: Step 1: placing a sample to be tested (22) on a three-dimensional motion console (21), and emitting laser light from a laser generating module (33); Step 2, point light source optical path (32) adjusts the laser to form a point light source, and guides the light of the point light source to the area of ​​the sample to be detected (22), the detection focus optical control module (23) focuses the light of the point light source on the surface of the sample to be detected (22), the point information receiving channel (15) receives the Raman signal excited by the point light source, and the Raman spectrometer (13) converts the Raman signal into an electrical signal; by adjusting the focus position and the three-dimensional motion control console (21), the focus position exist The peak frequency of each measuring point is extracted by the field-point information joint analysis module (12). and press z The coordinates are arranged in order, and the adjacent frequency difference is greater than the threshold N The characteristic frequency value of Forming basis vectors , different eigenfrequency values ​​of the basis vectors Represents different types of water; Step 3: The surface light source optical path (31) adjusts the laser to form a surface light source, and guides the surface light source light to the area of ​​the sample to be detected (22). The detection focus optical control module (23) focuses the surface light source light on the surface of the sample to be detected (22). The field information receiving channel (14) receives the Raman signal excited by the surface light source, and the Raman spectrometer (13) converts the Raman signal into an electrical signal. The Raman spectrum is analyzed by the field-point information joint analysis module (12) in the form of basis vectors. The characteristic frequency value in Decompose and use Gaussian function to fit the curve, and then get the water content of each combination type; Step 4: According to the characteristic frequency peak and different characteristic frequency peaks Gaussian decomposition peak area Calculate the field average spectral weighted peak frequency and define the average moisture consolidation degree Represents the average bonding strength between water and solid, and substitutes each characteristic peak frequency Get the degree of consolidation corresponding to the moisture type.

7. The Raman spectroscopy analysis method for particle water binding strength and content according to claim 6, characterized in that: The method for obtaining the water content of each combination type in this method is specifically as follows: The Raman spectrum is based on the basis vector The characteristic frequency value in Decompose and use Gaussian function for curve fitting: In the formula, are different characteristic frequency peaks Gaussian decomposition peak area, water content of each binding type It is expressed as: 。 8. The Raman spectroscopy analysis method for particle water binding strength and content according to claim 7, characterized in that: The specific method of the consolidation degree corresponding to the moisture type in this method is: Calculate the field-averaged spectrally weighted peak frequency : Defining the average moisture content The average strength of water-solid bonding is as follows: In the formula, Represents the characteristic peak frequency of ice. For solid water such as ice, the water binding degree is 1; Represents the characteristic peak frequency corresponding to free water when the binding strength between water and solid is the lowest, usually the farthest from the measured Raman signal Peak frequency on one side The extreme value of Calculate the frequency of each characteristic peak Degree of consolidation corresponding to moisture type: for The greater the moisture content, the higher the degree of consolidation.

9. The Raman spectroscopy analysis method for particle water binding strength and content according to claim 6, characterized in that: In the method, a point light source Raman spectrum signal of the degree of binding between water molecules and solid particles is obtained by a point light source optical path (32), and water molecule peak frequency information reflecting the degree of binding between water molecules and solid particles is extracted. The water molecule and solid binding state information is contained in the peak frequency of the spectrum; a field light source Raman spectrum signal of the degree of binding between water molecules and solid particles is obtained by a field light source optical path (31), and different types of water contents are obtained by inverting from the field Raman spectrum signal.

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