99 results about "Absorption spectroscopy" patented technology

The invention discloses a distinguishing table type X-ray spectrometer and an X-ray absorption spectrum testing method, and relates to the technical field of spectral measurement. The high-resolution table type X-ray spectrometer comprises a sample signal source which is located in a Dowland circle and is used for generating X-rays; the exponential crystal is a bent crystal, the surface shape of the exponential crystal is defined by an exponential equation, so that different points on the curved surface of the crystal have different curvature radiuses and correspond to Rowland circles with different radiuses, each point on the exponential crystal is tangent to the corresponding Rowland circle, and the exponential crystal is used for performing monochromatization and focusing on the X-ray incident from the sample signal source; and the detector is positioned on a surface formed by the corresponding imaging points on each Rowland circle, and is used for receiving the X-rays which are monochromatized and focused by the index crystal and outputting corresponding light intensity signals. Therefore, through the cooperation of the index crystal and the multi-Rowland circle structure, the X-ray absorption spectrum test with high light receiving efficiency, high spectral resolution and wide energy spectrum range can be realized, and the comprehensive performance of the desk type spectrometer is improved.

The embodiment of the invention provides a method for determining initial parameters of a transient absorption spectrum kinetics curve, and the method comprises the steps: obtaining an initial absorption point and an absorption attenuation termination point of the transient absorption spectrum kinetics curve, and determining a curve segment between the initial absorption point and the absorption attenuation termination point as a total absorption attenuation interval; carrying out weighting processing on a first-order derivative and a second-order derivative of the transient absorption spectrum dynamic curve to obtain a weighted curvature value sequence; the first N-1 weighted curvature values are selected from the weighted curvature value sequence from large to small, and the total absorption attenuation interval is divided into N absorption attenuation intervals corresponding to curve fitting orders according to sampling points corresponding to the first N-1 weighted curvature values; and determining an initial parameter based on a quantitative relationship of 1 / e of the absorption intensity attenuated to the corresponding interval starting point in each absorption attenuation interval in the exponential fitting model, wherein the quantitative relationship is that the absorption intensity at the interval starting point in each absorption attenuation interval is attenuated to the absorption intensity at the corresponding interval starting point. And the fitting efficiency and accuracy of the dynamic curve are improved.

The invention provides an X-ray absorption spectrum characterization system and an X-ray absorption spectrum characterization method for electrochemical reaction under a high-current working condition. A high-current electrochemical workstation provides current density not lower than that of a working condition electrolytic tank; the working condition electrolytic tank comprises a working electrode chamber and a counter electrode chamber which are oppositely arranged, and an ion exchange membrane arranged between the working electrode chamber and the counter electrode chamber; the working electrode chamber comprises a current-conducting plate made of a metal sheet, a working electrode loaded with a catalyst is arranged on one side, facing the ion exchange membrane, of the current-conducting plate, and a hollow flow channel is formed in the central area of the working electrode chamber; the working electrode chamber further comprises an X-ray window sheet for transmission of incident X-rays and fluorescent X-rays generated by the catalyst; the counter electrode chamber is provided with an electrolyte flow channel, and a counter electrode is arranged on one side, facing the ion exchange membrane, of the counter electrode chamber; and the electrolyte control system is used for realizing circulating flow of the electrolyte. Under the working conditions of high current density, strong bubble effect and high X-ray absorption, in-situ, real-time and high signal-to-noise ratio characterization of the microstructure of the catalyst can be realized.

The invention relates to the technical field of spectral measurement and analysis, and discloses an in-situ cell for rapid and continuous synchrotron radiation X-ray absorption spectrum measurement, the in-situ cell comprises a housing 1, one side of the housing 1 is provided with two through holes, and a counter electrode and a reference electrode are respectively fixed in the two through holes; the first shell and the second shell are correspondingly arranged, and square optical windows are arranged in the center of the second shell and the center of the first shell; the first shell and the second shell are each provided with a hole channel, the two hole channels are located on the two sides of the square optical window respectively, and a working electrode is fixedly arranged between the second shell and the first shell. The in-situ synchrotron radiation X-ray absorption spectrum measuring device is suitable for in-situ synchrotron radiation X-ray absorption spectrum measurement in a time-resolved energy dispersion / transmission mode, and through real-time supply and circular flow of the electrolyte on the surface of the working electrode, the uniformity of the X-ray penetrating through a solution layer is ensured, the elimination of product gas is accelerated, the influence of solution disturbance on a test signal is reduced, and the test stability is improved.

This invention discloses a method for detecting polycyclic aromatic hydrocarbons (PAHs) based on ultraviolet fluorescence and absorption spectroscopy, comprising: Step 1, acquiring the ultraviolet absorption spectrum and the fluorescence emission spectrum of a water sample under ultraviolet light excitation; Step 2, analyzing the corresponding CDOM fluorescence spectrum using the ultraviolet absorption spectrum obtained in Step 1; Step 3, subtracting the CDOM fluorescence spectrum obtained in Step 2 from the fluorescence emission spectrum obtained in Step 1 to obtain a mixed fluorescence spectrum containing multiple PAHs; Step 4, performing multivariate fitting on the mixed fluorescence spectrum obtained in Step 3 to obtain the type and concentration of each PAH in the water sample. This invention also provides a PAH detection device. The method provided by this invention is simple to operate and can directly detect raw water samples, thereby obtaining more accurate PAH detection results.

A method suitable for controlling polymerization reactions in resin manufacturing is provided. A manufacturing method comprising a step of causing reactants to undergo a polymerization reaction, the manufacturing method including measuring at a frequency of 9400–4500 cm⁻¹ －1 The process includes a spectral determination step that uses near-infrared absorption spectroscopy of the polymerization reaction mixture within a certain range to determine the extent of the polymerization reaction, and a viscous behavior determination step that uses the viscous behavior of the polymerization reaction mixture to determine the extent of the polymerization reaction.

The utility model relates to gas detection technical field, the utility model provides a kind of LNG dual-fuel ship exhaust monitoring device, using ultraviolet differential absorption, non-dispersed infrared absorption and tunable semiconductor laser absorption spectroscopy etc. Optical detection principle realizes the synchronous detection of four kinds of gases SO2 (0~1500ppm), CO2 (0~30%), CH4 (0~1500ppm) and NO (0~1500ppm), error is controlled within ±2%FS, response time is not more than 30s. Realize LNG dual-fuel characteristic gas accurate detection simultaneously, with the advantages of high detection precision, fast response speed, simple operation, relatively low cost and strong gas cross-interference resistance ability under complex working conditions.

1. The name of the design product: high-precision transient absorption spectrum detection device. 2. The use of the design product: for ultrafast time-resolved spectral detection, analyzing the transient absorption characteristics of materials after light excitation, suitable for kinetic studies in the fields of chemistry, materials science, biomedicine, etc. 3. The design points of the design product: in shape. 4. The picture or photo that best indicates the design points: perspective view 1.

An apparatus comprising a compact folded path cell for optical gas detection and / or measurement utilizing gas absorption spectroscopy. The apparatus includes an electromagnetic radiation source, a gas sample cell housing a reflector, and a detector for electromagnetic radiation. The source and detector are positioned between the reflector elements in a configuration that reflects the radiation away from the source and detector until the reflected radiation has a suitable optical path length, and then reflects the radiation towards the detector. Using spectroscopic analysis, the presence of at least one gas species in a gas sample can be determined and / or at least one parameter can be measured.

The invention relates to the technical field of sewage treatment, and discloses a system and a method for inhibiting nitrous oxide release in a sewage denitrification process, and the system comprises a water inlet unit, a denitrification reaction unit, a dissolved oxygen monitoring module, a central control unit, a gas collection unit and a performance evaluation module. The multi-point arrangement and encryption communication mode of the dissolved oxygen monitoring module improves the accuracy and safety of data acquisition, and the corrosion-resistant design of the gas collection unit and infrared absorption spectrometry detection ensure the reliability of gas analysis. The central control unit realizes the adaptive capability of the system through real-time monitoring and dynamic adjustment, and the performance evaluation module improves the long-term operation efficiency of the system through data analysis and optimization suggestion generation. According to the method, a dissolved oxygen dynamic balance regulation mechanism and a multi-parameter collaborative optimization strategy are introduced, and a real-time monitoring and feedback control technology is combined, so that the problem of generation of byproducts in the nitrification and denitrification process is solved, and the release amount of nitrous oxide is effectively reduced.

This invention discloses a retrieval enhancement generation method for terahertz absorption spectroscopy diagnostics. The method includes: collecting terahertz absorption spectral data of biochemical substances; establishing a terahertz absorption spectral text structure database; establishing a terahertz absorption spectral image structure database; establishing a terahertz absorption spectral structure database; constructing a text vector library in the field of terahertz spectroscopy detection; determining the user question type and extracting structured information; if the user question is a terahertz absorption spectroscopy diagnostic question, then analyzing influencing factors and generating a query question, rewriting the user question into a query question; retrieving the text vector library in the field of terahertz spectroscopy detection based on the query question; generating an answer through a large language model and returning it. This method analyzes and calculates the influencing factors of terahertz absorption spectroscopy based on a structured database and rewrites the query question into a query question more suitable for RAG retrieval, improving the efficiency of researchers in diagnosing absorption spectra and retrieving knowledge in the field of terahertz spectroscopy detection.

The invention provides a wide-temperature-range electrochemical in-situ X-ray absorption spectrum testing device which comprises a heat conduction table, a plurality of temperature control surfaces are arranged on a main body of the heat conduction table, and the plurality of temperature control surfaces are adjacent to each other to form a polygonal enclosed structure; the heat conduction table main body is further provided with a temperature controlled surface, the temperature controlled surface is arranged on one side of the polygonal enclosure structure, and through the design that the plurality of temperature control surfaces of the heat conduction table are of the polygonal enclosure structure and refrigeration and heating are carried out through the temperature control assembly, rapid and accurate wide-temperature-range temperature control on the test groove of the temperature controlled surface is realized; and the test groove is used as a battery carrying platform and is matched with the battery clamp to realize quick replacement of the button battery, so that the test efficiency is greatly improved.

This invention discloses a multidimensional transient absorption spectroscopy measurement device, comprising a pump-probe mechanism and a two-dimensional spectroscopy mechanism. The pump-probe mechanism includes a first pump optical path, a second pump optical path, a probe optical path, and a first delay module. The first pump optical path generates a first pump light to excite the sample, the second pump optical path generates a second pump light to excite the sample, and the probe optical path generates a probe light to monitor the excited-state particle number information of the sample. The first delay module is disposed in the first pump optical path and is used to control the first pump light to illuminate the sample after a first delay time relative to the second pump light. The two-dimensional spectroscopy mechanism includes a fourth focusing element, an optical path deflection component, a beam splitting component, and a two-dimensional surface array detector. This invention integrates a surface array detector and a specific optical path design, enabling simultaneous detection of the multidimensional transient absorption spectrum information of the sample. Combined with multiple independently controllable pump light sources and their delay mechanisms, it achieves rapid three-dimensional measurement.

The invention discloses a methane telemetering imaging system and method based on an active infrared absorption spectrum and a fast reflector, and the system comprises a main control module, a laser driver, a laser, a detector, an off-axis parabolic reflector, a voice coil fast reflector, and a distance measurement module. The laser driver controls the laser device to emit modulated laser, the voice coil fast reflecting mirror controls the angle of emergent laser, the semiconductor photoelectric detector receives an echo optical signal, converts the echo optical signal into an electric signal and sends the electric signal to the main control module, and the main control module further completes signal analog-to-digital conversion through an analog-to-digital converter. And a digital lock-in amplifier is used to demodulate the signal to respectively obtain a first harmonic and a second harmonic. The method has the advantages of high imaging speed, high spatial resolution, high detection sensitivity and the like.

To improve the measuring sensitivity of a component contained in a gas sample without increasing the cost required in the introduction of a gas absorption spectroscopic system.SOLUTION: The gas absorption spectroscopy system includes a resonator, a light source, a driving device, a control device, and a detector. The resonator includes a first mirror and a second mirror. The light source irradiates the resonator with laser light. The driving device changes a length between the first mirror and the second mirror. The control device controls the drive device. The detector outputs a detection signal corresponding to the detected light to the control device. The drive device sweeps at least one of the first mirror and the second mirror in a wave shape around a sweep center, and adjusts a length between the sweep center and the second mirror to a length between the first mirror and the second mirror when the detection signal is acquired in response to the acquisition of the detection signal by the control device.SELECTED DRAWING: Figure 8

The application provides a full fluorescence yield detector for in-situ soft X-ray absorption spectroscopy, which is based on a photomultiplier and can collect weak fluorescence signals excited by soft X-rays under in-situ conditions (reactions under simulated complex environment conditions). A large-diameter photomultiplier is used and the top angle of the detector is improved to increase the fluorescence collection angle as much as possible to improve the signal strength; double gold meshes are used and different voltages are added to shield interference signals such as photoelectrons and positive ions of non-fluorescence yield at the same time; a spliced half-cylinder barrel design is used to realize shielding and facilitate maintenance and replacement of the photomultiplier; a spring and rubber pad are used in cooperation with a screw to fasten the mode, which can maintain good electrode contact while avoiding overpressure damage to the photomultiplier and can work stably in a vibrating environment. The application optimizes the detector from the aspects of the structure of the detector, detection efficiency, signal interference shielding, maintenance convenience and the like.

The quantum optical system changes a phase of quantum interference occurring between a plurality of physical processes, in each of which a quantum entangled photon pair of a signal photon and an idler photon is generated. Each of a plurality of pixels outputs a detection signal of the signal photon in a state where a sample is arranged in an optical path of the idler photon. A processor calculates an absorption spectroscopy characteristic based on an interferogram indicating a variation in a signal intensity acquired from each of the plurality of pixels in accordance with the change in the phase of the quantum interference. The processor: applies a processing to reduce phase difference of the interferogram among the plurality of pixels; spatially integrates, over the plurality of pixels, the interferogram having gone through the processing to reduce phase differences; and calculates the absorption spectroscopy characteristic based on the integrated interferogram.

The invention relates to a system for determining cellular respiration and nutrient metabolism of living cells or tissues, the system comprising: a cell container configured to receive and maintain a biological sample; a gas volume in fluid communication with the cell container, the gas volume containing gaseous components produced by metabolic activity of the biological sample; an optical detection unit configured to detect a target gas species in the gas volume by wavelength-selective absorption spectroscopy, the optical detection unit being further configured to distinguish between different isotopic species of the target gas species, the optical detection unit comprising an illumination source and detector arrangement optically coupled to the optical detection unit and configured for measurement of absorption signals corresponding to different isotopes of the target gas species; and an electronic control and evaluation unit operatively connected to the optical detection unit, the electronic control and evaluation unit being configured to acquire and process absorption data, determine absolute values and / or temporal variations of the target gas species concentration and isotopic composition, and output respiration-related parameters of the biological sample. In this way, a system is provided that enables precise and efficient determination of carbon dioxide produced by living cells or tissues under physiological conditions.

The invention belongs to the technical field of environmental salt mist concentration measurement, and particularly relates to a salt mist concentration measurement system and method based on laser scattering and absorption spectrum, which can obtain the mass concentration of salt mist liquid drops and the concentration of chloride ions in the liquid drops, further obtain the quantitative result of the salt mist concentration and realize the rapid and accurate measurement of the salt mist concentration. Aiming at the problem of inaccurate online measurement of the salt mist concentration, the invention innovatively proposes simultaneous measurement of a laser scattering signal and a laser absorption spectrum, measurement of the mass density of salt mist liquid drops through the scattering signal and correction of a laser absorption signal. The concentration of chloride ions is obtained through the laser absorption spectrum, and then the salt mist concentration is calculated. According to the invention, on-line and accurate measurement of the environmental salt mist concentration can be realized.

An apparatus for compact, folded path optical gas detection / measurement in gas absorption spectroscopy, comprises; a gas cell 307 for containing gas to be analysed with gas exchange ports 308 and at l

This invention discloses a method for spatial sampling and reconstruction of ozone concentration distribution in a dielectric barrier discharge device, belonging to the field of ozone concentration measurement and image reconstruction technology. The method includes: setting up a sampling area in the vicinity of the discharge device and defining orthogonal sets of first and second measurement lines; measuring the measurement lines using an absorption spectroscopy measurement device to obtain two sets of orthogonal one-dimensional projection measurement data; controlling the sampling sequence through a stability criterion after switching measurement lines; performing windowing processing and frequency domain analysis on the projection sequence to obtain spectral information; constructing a two-dimensional frequency domain representation and applying physical prior constraints; performing a two-dimensional inverse transform to obtain initial values ​​of the lattice, and outputting a continuous distribution result after spatial reconstruction and refinement. This invention can achieve reliable retrospective reconstruction of the ozone concentration field under conditions of limited projection measurement data and asynchronous measurements, providing a basis for spatial distribution diagnosis and performance evaluation of the ozone generation process in dielectric barrier discharge.

The utility model discloses a 4-series laser gas sensor, relates to the technical field of gas sensors, and solves the problem of poor detection sensitivity of a gas sensor in the prior art. The device comprises a shell, a laser and a detector are arranged in the shell, a plurality of reflecting surfaces are arranged in the shell, an optical cavity is formed among the reflecting surfaces, the reflecting surfaces are matched with the laser and the detector, and laser emitted by the laser can be reflected to the detector under the reflecting action of the reflecting surfaces. The laser is reflected between the reflecting surfaces and penetrates through the optical cavity for at least three times, and the optical cavity is communicated with the outside of the shell. The optical cavity is arranged, the internal space for containing and detecting the gas is provided, and the laser can be emitted by the laser, penetrates through the gas to be detected and is received by the detector, so that the gas to be detected can be detected by a laser absorption spectrum technology, and the detection precision, the sensitivity and the anti-interference capability are improved. And by increasing the laser optical path, the mirror surface utilization rate is improved, and miniaturization development is facilitated.

This invention provides a method for analyzing the femtosecond laser-induced damage behavior of Zn-doped KDP crystal surfaces, belonging to the field of engineering optics technology based on computer data processing. First, the effects of Zn doping concentration on the bandgap and electroacoustic coupling of the KDP crystal are analyzed using UV-Vis absorption spectroscopy and Brillouin scattering spectroscopy, respectively. Then, a one-dimensional model is constructed, and the time evolution of electron density, lattice temperature, and electron temperature on the Zn-doped KDP crystal surface under femtosecond laser irradiation is simulated using a rate equation for electron density accumulation and a two-temperature model. The influence of Zn doping concentration on the damage behavior of the KDP crystal surface is theoretically analyzed, and a theoretical model for calculating the femtosecond laser-induced damage threshold is established, thus non-destructively determining the optimal Zn doping concentration. This invention avoids contact with real samples, improving sample utilization; the simulation process is more stable and controllable with high data repeatability; it can also shorten the research cycle and accelerate the selection of the optimal doping concentration.

This invention provides a gas detection method based on non-dispersive infrared absorption spectroscopy, comprising the following steps: (A1) Measurement light emitted from a light source passes through a chopper, the rotation speed of which changes periodically; after passing through the chopper, part of the measurement light passes through a sample cell and enters a first container filled with the gas to be measured, and part of the measurement light passes through a reference cell filled with a gas containing zero content of the gas to be measured and enters a second container filled with the gas to be measured; a conversion unit senses the periodic changes in gas pressure in the first and second containers and outputs electrical signals; zero gas and standard gas of the gas to be measured are respectively introduced into the sample cell, and the conversion unit outputs electrical signals V0(t) and V... span (t), where t is time; (A2) Fit the function F0(t) = V span (t)-V0(t); (A3) The sample gas to be tested is introduced into the sample cell, and the conversion unit outputs an electrical signal V(t); (A4) The fitting function F(t)=V(t)-V0(t)=A·F0(t)+B, where A and B are the fitting parameters; (A5) The concentration of the gas to be tested in the sample gas is obtained as C=A·C span C span This refers to the concentration of the gas being measured in the standard gas. This invention has advantages such as small detection error.

Apparatus for gas detection using gas absorption spectroscopy, comprises; gas cell 805 with at least one gas exchange port; at least one radiation source 801 arranged to transmit a diverging beam thro

A quantum absorption spectroscopy system (1) includes a pump light source (11), a quantum interferometer (21), and a spectroscope (31). The pump light source (11) emits pump light. The quantum interferometer (21) causes quantum interference between a plurality of physical processes in which a quantum entanglement photon pair of a signal photon and an idler photon is generated through spontaneous parametric down-conversion of the pump light, a sample being arranged on a propagation path of the idler photon. The spectroscope (31) detects a signal photon from the quantum interferometer (21). The quantum interferometer (21) includes a single mode fiber (SMF) portion optically coupled to at least part of a propagation path of the signal photon and the propagation path of the idler photon.

The invention discloses a monochromator system based on a transmission grating, which comprises a monochromator chamber, two ends of the interior of the monochromator chamber are respectively provided with a slit entering frame and a grating adjusting frame, a mirror bracket is arranged between the slit entering frame and the grating adjusting frame, a focusing toroidal mirror is arranged on the mirror bracket, and the transmission grating is arranged on the grating adjusting frame. An extension rod is arranged at the front end of the monochromator chamber, and a light source is arranged at the end of the extension rod. The device has the advantages that under the condition that the solid angle of the transmission grating is not changed, the incidence angle of the grating is changed through the rotation angle of the grating adjusting frame, light with different wavelengths is output at the same angle after being focused, it is guaranteed that the focused light can be output through the fixed outlet seam, and the device is compact in structure, low in cost and convenient to use. Precise diffraction and stable focusing of soft X-rays can be achieved, and the method is applied to a laser plasma light source and meets the application requirement of the ultra-fast soft X-ray absorption spectrum technology.

Provided are a composition obtained by separating and recovering a component, which is derived from PBT, from a raw material containing PBT together with another polymer while suppressing contamination of a component derived from the other polymer, and a method for obtaining such a composition.　This oligomer composition contains a butylene terephthalate (BT) oligomer in which both ends are terminated with 1,4-butanediol (14BD), and does not contain PA or PET, or a decomposition product thereof in an amount detectable by infrared absorption spectroscopy. This production method includes: a first separation step for heating, in 14BD, a raw material mixture at a first temperature equal to or higher than the dissolution start point of PA and lower than the dissolution start point of PBT to isolate an insoluble product; a second separation step for heating, in 14BD, the insoluble product obtained in the first separation step at a second temperature equal to or higher than the dissolution start point of PBT and lower than the dissolution start point of PET to isolate a dissolved and separated component; and a solvent removal step for removing a solvent from the dissolved and separated component obtained in the second separation step.

This invention provides a high-precision and rapid imaging method using dual-comb absorption spectroscopy, mainly comprising: First, describing the gas parameter distribution in the measured area using multiple temperature-concentration pairs, obtaining the dual-comb absorption spectrum projections passing through multiple optical paths in this area; utilizing the high energy concentration characteristic of dual-comb absorption spectra in the time domain, performing an inverse Fourier transform on the spectrum, retaining the energy-concentrated segments, and obtaining the dual-comb time-domain absorption signal projection; Second, substituting the dual-comb time-domain absorption signal projection into a multi-optical-path temperature-concentration histogram time-domain inversion model to reduce the model dimensionality, and solving the model to obtain the temperature-concentration histogram matrix; Finally, substituting the histogram matrix into a temperature-concentration discrete reconstruction model to achieve high-precision imaging of the spatial distribution of temperature and concentration. This invention fully utilizes the rich data of dual-comb absorption spectra to improve reconstruction accuracy, while combining its energy concentration characteristic in the time domain to improve reconstruction speed, thus achieving high-precision and rapid imaging of temperature and concentration.