21 results about "Molecular absorption" patented technology

The invention relates to the technical field of near-infrared light analysis materials, in particular to a near-infrared spectrum noninvasive blood glucose concentration dynamic detection method which comprises the steps that a plurality of training samples and blood near-infrared spectrum current data of the current blood glucose concentration to be detected are collected, and the training samples are blood near-infrared spectrum historical data of different blood glucose concentrations; determining a water molecule absorption peak value in the blood near infrared spectrum historical data and the blood near infrared spectrum current data, a corresponding wavelength thereof, and a difference between the water molecule absorption peak width, and obtaining the availability degree of each training sample; the mathematical regression model weight of each training sample is obtained based on the availability degree of each training sample and the collection time of each training sample, so that the mathematical regression model weight of each training sample is more reliable and accurate, the accuracy of the mathematical regression model is improved, and finally the accuracy of blood glucose concentration detection is improved.

The invention discloses a honey adulteration detection method, which belongs to the technical field of food detection, and comprises the following steps: collecting an absorbance spectrum of a honey sample by using a near infrared spectrometer; extracting characteristic absorbance values A < lambda > 1 and A < lambda > 2 at a 1450 nm water molecule absorption peak and a 1490 nm saccharide molecule absorption peak; the ratio R is equal to A lambda 1 / A lambda 2; and comparing the R with a threshold range of 0.85-1.15 of pure honey so as to judge whether the honey is true or false. The portable device comprises a sample bin, a near infrared spectrum module, a control unit and a human-computer interaction interface, wherein a rotatable sample table is arranged in the sample bin to accommodate a plurality of disposable sample cups. The method abandons a complex black box model, adopts a characteristic wavelength ratio method with clear physical significance, has the outstanding advantages of simple principle, rapid detection (less than 30 seconds), high accuracy, low cost, simplicity and convenience in operation and the like, perfectly solves the problems of expensive equipment, long time consumption, limited identification capability and dependence on professionals in the prior art, and has a wide application prospect. The method is especially suitable for market on-site rapid screening.

This invention provides a gas-phase molecular absorption spectrometry-naphthylethylenediamine hydrochloride spectrophotometric method for determining total nitrogen in waste gas from stationary pollution sources. The method comprises the following steps: S1. Reacting the waste gas with an oxidant; S2. Using an absorbent, further reacting the waste gas after S1; S3. Collecting the oxidant after S1, pretreating it to reduce nitrogen-containing compounds to nitric oxide, and detecting the total nitrogen content I; S4. Collecting the absorbent after S2 to obtain the total nitrogen content II; S5. Summing the total nitrogen content I and total nitrogen content II to obtain the total nitrogen content in the current waste gas. This method enables accurate determination of total nitrogen in waste gas from stationary pollution sources.

This invention discloses a data processing method for carbon dioxide column concentration based on a spaceborne lidar, comprising: performing nonlinear correction on the spaceborne integral path differential absorption (IPDA) lidar detection signal; calculating the differential optical thickness based on the IPDA lidar signal; calculating the echo height above sea level and geographic coordinates based on the echo signal location; establishing an absorption cross-section lookup table using differential absorption cross-section data from the High Resolution Transmission Molecular Absorption (HITRAN) database; calculating the pressure at the echo location using the European Centre for Medium-Range Weather Forecasts Reanalysis Dataset (ERA5) and the echo signal height above sea level; calculating the Doppler frequency shift; calculating a weighting function based on pressure profiles, humidity profiles, temperature profiles, and Doppler frequency shift data; and calculating the carbon dioxide column concentration. The key features of this invention are the nonlinear correction of the spaceborne IPDA lidar echo signal, the establishment of a differential absorption cross-section lookup table for carbon dioxide molecules, and the accurate and efficient calculation of the carbon dioxide column concentration using spaceborne IPDA lidar detection data and ERA5 meteorological dataset data.

The invention discloses a molecular spectrum scanning device and method based on cavity enhancement. The molecular spectrum scanning device comprises a stepping motor, a laser, a cavity enhancement spectrum system, a PDH locking system, an optical frequency comb, a wavelength meter, a spectrum data acquisition card, an industrial personal computer and a voltage amplifier. Through the PDH locking technology, the scanning laser frequency tracks the resonance mode of the optical resonant cavity in real time, the lock losing problem in the scanning process is solved, and high stability is ensured; meanwhile, an optical frequency comb is used as a frequency scale, and real-time and accurate absolute frequency measurement is carried out on the scanning laser through a wavemeter; active frequency locking and absolute frequency calibration technologies are organically combined, high-sensitivity, high-frequency-precision and high-stability cavity enhanced molecular absorption spectrum measurement is achieved, and the method is particularly suitable for the fields of trace gas detection, precision spectroscopy, atmospheric environment monitoring and the like.

The application discloses an aerosol correction method and system suitable for a hyperspectral resolution laser radar, and relates to the technical field of laser radar detection. Specifically, the method comprises the following steps: a first auxiliary detection channel and a second auxiliary detection channel specially added and containing iodine molecular absorption cells are used to filter out aerosol Mie scattering components in specific frequency laser echoes; pure first atmospheric temperature data is obtained based on data inversion of the auxiliary detection channels; atmospheric aerosol backscattering ratios are calculated in combination with reference channel data; the backscattering ratios are used to correct wind speed and temperature inversion models of the laser radar, and then corrected atmospheric wind speed and temperature data are obtained. The application aims to expand the minimum detection height of a hyperspectral resolution Rayleigh temperature and wind measurement laser radar by accurately quantifying and eliminating aerosol interference, and to realize high-precision synchronous measurement of wind speed and temperature in low-altitude and aerosol-rich areas.

A kind of lidar technology for atmospheric waveguide fast measurement, temperature and humidity profile, the key factor of atmospheric waveguide, can be measured simultaneously, the device includes laser emission module: 822nm online seed laser, 822nm offline seed laser, 1064nm pump laser, laser frequency locking module, optical parametric oscillator, acoustooptic modulator, frequency doubling module and emission optical assembly;Echo receiving module: optical receiving telescope and optical lens assembly, F-P filter, polarization light splitting prism, iodine molecular absorption cell, Fizeau interferometer and photodetector;Data acquisition and processing module.The present application fuses differential absorption lidar and two detection systems based on interferometer high spectral lidar, adopts seed injection optical parametric oscillator laser technology, obtains high frequency stability 822nm laser to realize atmospheric humidity profile fast measurement, remaining 532nm laser realizes atmospheric temperature profile fast measurement, finally inverts atmospheric waveguide parameter, realizes atmospheric waveguide efficient and accurate measurement.

Present invention relates to a needle-free glucose measurement system which enable measurement of blood glucose level using concentration value of N2O molecule available in breath air, which comprises an electronic assembly (1.1) which stabilizes the temperature and flow of wavelength-adjustable laser light source (1.2) and controls wavelength, a laser-based sensor (1) which determines concentration values of N2O molecule by measuring the adsorption amount of detector (1.5) wherein beams coming from laser light source (1.2) are adsorbed by N2O molecules in the breath air in the adsorption cell (1.4), and a processor (2) which determine glucose values in the blood using the concentration data coming from laser-based sensor (1).

This invention provides a foam elimination method and apparatus, relating to the field of defoaming technology in the filling process. It utilizes a laser generator to produce a laser beam, which is transmitted to a homogenizer. The homogenizer shapes the laser beam into a planar spot for output. The wavelength of the laser is located in the absorption peak band of liquid water. The energy of the laser is absorbed by water molecules in the foam liquid film and converted into heat energy, causing the liquid film to vaporize instantaneously and break up the foam. The advantages of this invention are that it uses laser light incident from the side of the container, directly utilizing the thermal effect to vaporize the foam liquid film, avoiding complex acoustic wave conversion and conduit structures; it is unaffected by liquid color and transparency; the laser spot can be pre-adjusted to cover the foam area, eliminating the need for dynamic focusing during filling; and it does not damage containers such as PET, PE, or glass, achieving a highly efficient and stable online defoaming function.

The present invention is directed to a sample holder for use in molecular absorption spectroscopy. The sample holder comprises a first surface having a first predetermined geometry, and a second surface having a second predetermined geometry. The first surface is opposite the second surface. The sample holder is configured to hold a measurement sample between the first surface and the second surface such that a distance between the first surface and the second surface defines an optical pathlength of the sample holder. The predetermined geometries of the first surface and the second surface provides a continuously variable cross-section across the sample holder so as to provide a continuous range of optical pathlengths.

The application belongs to the technical field of optical sensing, and particularly relates to a high-resolution wavelength demodulation device based on laser beat frequency technology, the main structure of which comprises a reference light path and a sensing light path connected with a measuring light path respectively; the measuring light path, the reference light path and the sensing light path are connected with the measuring light path respectively, a gas molecule absorption line is introduced as a reference frequency, laser frequency measurement is reduced from a terahertz wave band to a low-frequency wave band which is easy to measure through an optical heterodyne detection scheme, high-resolution measurement is carried out through an oscilloscope and a frequency meter, and the device has extremely high resolution and long-term stability; the device has the advantages of simple structure, high resolution, good stability, fast response speed, high signal-to-noise ratio and the like, and is suitable for demodulating high-precision optical resonant cavity sensors.

This invention discloses a high-precision gas parameter measurement system and method based on the harmonic reconstruction principle, belonging to the field of data processing technology. The method includes the following steps: S1, processing the modulated transmittance signal to obtain harmonic curves from order 0 to k0; S2, obtaining the variation curves of each order harmonic with respect to the laser frequency based on the laser frequency variation signal and the harmonic curves from order 0 to k0; S3, determining the molecular absorption spectrum based on the variation curves of each order harmonic with respect to the laser frequency; S4, analyzing the molecular absorption spectrum to determine the physical parameters of the gas being measured. This invention retains the core advantages of wavelength modulation spectroscopy, such as high signal-to-noise ratio, strong anti-interference capability, and high measurement accuracy, while providing a new measurement method for high-precision calibration of spectral physical parameters, high-precision measurement of gas parameters under weak absorption conditions, and gas monitoring in complex industrial environments, effectively expanding the measurement efficiency and application scope of this technology.

The application discloses an amyloid configuration optical detection method based on infrared waveband multi-frequency resonance, which comprises the following steps: obtaining an optical super-structure surface unit; adding an amyloid solution to be detected; irradiating incident light to realize electromagnetic field excitation; detecting the refractive index and layer thickness of a protein formation layer in a groove of a coupling complementary opening resonance ring working in a near-infrared waveband to obtain one-dimensional structure information of the amyloid formation layer to be detected; detecting the component molecule configuration in the groove of the coupling complementary opening resonance ring working in a mid-infrared waveband by using a characteristic absorption peak of a molecule to obtain structure information of the amyloid molecule to be detected; and determining the configuration analysis result of the amyloid to be detected and the relationship between the protein formation layer and the protein component molecule configuration by using the two aspects of information. The application realizes the measurement based on the medium refractive index and the measurement based on the molecular absorption spectrum on the same sensing surface, can realize the protein configuration analysis and organically connects the layer structure and the molecule configuration.

The invention is suitable for the technical field of laser measurement, and provides a compact laser frequency automatic long-term locking system and method, which can obtain an absorption spectrum through triangular wave scanning by adjusting the laser wavelength to be close to a target spectral line. Parameters such as spectral line number, amplitude and distance threshold are set, a target spectral line is automatically identified, and a corresponding voltage value is recorded. And then, through fast and slow PID control, the frequency is locked at a spectral line zero crossing point through PZT and temperature adjustment. And the system monitors the frequency discrimination signal in real time, the PID is closed if the lock is lost, the output value is kept to avoid frequency hopping, then the target spectral line is re-identified through small-range oblique wave scanning and locking is recovered, and long-term stable automatic frequency locking is realized. Therefore, the device can realize many application scenes of laser frequency locking based on the atom / molecule absorption cell, is very suitable for research of high-precision and advanced physical experiments and interference measurement technologies in which a frequency-stabilized light source participates, can fully ensure high accuracy of the laser light source, and can simplify an experiment or measurement device.

The invention relates to the technical field of automatic detection, and discloses a multi-mode needle cylinder liquid intelligent detection method, device and system, and the system comprises a multi-mode imaging module, a dynamic calibration module, a volume calculation module and a man-machine interaction module. The multi-modal imaging module, the dynamic calibration module, the volume calculation module and the man-machine interaction module are jointly configured with a voice alarm module; by arranging a multi-mode imaging end, when the existence of liquid in a needle cylinder is detected, dual-mode data of visible light transmission light intensity distribution and near-infrared absorption spectrum are synchronously acquired, and dual criteria of the existence of the liquid are constructed, so that the liquid level refraction characteristic and the molecular absorption characteristic can be subjected to real-time cross validation; the method guarantees the discrimination of transparent liquid, a low-contrast medium and a bubble-containing medicament, eliminates the misjudgment risk of traditional single spectral imaging, and improves the reliability of liquid existence detection.

The invention discloses a wavelength optimization selection method for a three-wavelength differential absorption laser radar, and the method comprises the steps: introducing an intermediate wavelength between an online wavelength and an offline wavelength, and deducing a three-wavelength differential absorption laser radar inversion equation set; then, a gas absorption model is constructed based on a Voigt linear function, the relation between the absorption cross section of molecules and the temperature and the pressure intensity is established, and an equation set is established according to the temperature, the pressure intensity, the concentration, the laser wavelength and the radar signal power; and finally, discretizing the candidate wavelength interval, analyzing candidate wavelengths one by one by adopting a numerical iteration method, determining an optimal third wavelength by taking the minimum temperature inversion deviation as a criterion, and considering error influences such as molecular extinction and wavelength drift, so that high-precision atmospheric temperature and concentration multi-parameter inversion can be realized in a complex atmospheric environment. The system has good monitoring accuracy, high efficiency and practicability, and has important application value and wide market prospect.

This invention belongs to the field of optical sensing technology and relates to an in-situ calibration device for a temperature sensor based on laser frequency sweeping technology. The main structure includes a laser, an optical attenuator, an optical beam splitter, a first circulator, a second circulator, a gas molecule absorption cell, a sensing probe, a calibration probe, a photodetector, a data acquisition box, an industrial computer, a voltage output module, an analog-to-digital converter, a current controller, and a temperature controller. It uses a laser frequency sweeping system as the sensor demodulation system and a π-PSFBG as the temperature sensing probe. A gas molecule line, unaffected by ambient temperature, is introduced as a frequency standard to compensate for frequency drift caused by environmental noise in real time. A gallium dot bottle is introduced as an absolute temperature reference to provide an absolutely stable temperature environment for the calibration probe, thus calibrating the system frequency drift caused by the π-PSFBG. In-situ calibration technology achieves long-term stability of the temperature sensor. Its structure is simple and can achieve high-resolution and long-term stable measurement.

The application provides a correction method for matrix effect of graphite furnace atomic absorption method, comprising the following steps: checking the absorbance-time real-time signal of the highest concentration value of a standard curve according to a preset temperature rising program; if the absorbance-real-time signal is not ideal, optimizing the temperature rising program by using a sample to be measured to obtain an optimized temperature rising program; detecting the absorbance corresponding to the concentration point on the standard curve according to the optimized temperature rising program to obtain a standard curve; testing the standard curve; detecting the sample to be measured by using the standard curve method, correcting by using parallel samples and testing whether there is interference of matrix effect. In the application, the molecular absorption interference and light scattering interference phenomenon caused by the matrix effect can be partially displayed in the real-time signal of the graphite furnace atomic absorption spectrometer, and can be corrected and eliminated by optimizing the graphite furnace temperature rising program or combining the dilution enrichment program and the parallel sample detection method.

The application belongs to the technical field of density sensors, and relates to a fiber grating float type density sensing device based on laser sweeping technology. A pi-phase shift fiber grator is used as a sensitive element to improve sensitivity based on the advantage of narrow linewidth. A laser sweeping technology is used to establish a modulation-demodulation system to improve resolution and response time and realize real-time measurement and high-speed measurement. A gas molecule absorption cell is used as a standard wavelength reference to improve measurement accuracy based on the fact that a gas molecule absorption line is not affected by changes in external temperature and other factors. A cross-correlation algorithm is used to calculate the shift of the center wavelength of the pi-phase shift fiber grator relative to the absorption peak of the gas molecule absorption cell to improve measurement accuracy. When the density of the liquid to be measured changes, the buoyancy of the microcrystalline glass float changes, the pi-phase shift fiber grator senses the buoyancy, generates strain, and the center wavelength shifts. The time interval between the center wavelength and the absorption peak of the gas molecule absorption cell is calculated to demodulate the density of the liquid to be measured.

The invention discloses a single quantum state molecular beam preparation system, device and method.The system comprises a molecule excitation module and a laser output module, the molecule excitation module comprises a gas inlet pipeline and a molecular beam valve, and the gas inlet pipeline is used for injecting gas molecules to be excited into the molecular beam valve; the molecular beam valve is used for reducing gas molecules in various quantum states into ground states to obtain ground state molecular beams; the laser output module comprises a laser source assembly and a cylindrical convex lens, the laser source assembly is used for outputting continuous laser, the continuous laser passes through the cylindrical convex lens to obtain fan-shaped excitation laser, and the excitation laser is perpendicular to the flight direction of the ground-state molecular beam and intersects with the ground-state molecular beam. The photon energy and the molecular absorption energy level of the excitation laser intersect in time, the laser energy is not zero, the adiabatic excitation condition is met, and the excitation efficiency approaches 100%, so that adiabatic excitation is carried out by using the continuous laser, and efficient excitation is realized in a continuous spatial domain. The method is suitable for the technical field of molecular beam preparation.

The application discloses a frequency discrimination curve calibration system, method and device, and relates to the technical field of laser remote sensing. The system locks the output laser frequency of a first laser on an atom or molecule absorption peak with low concentration, and obtains an accurate frequency standard. The output laser of a second laser is combined with the output laser of the first laser to generate a tuning control signal of the second laser from a frequency difference extracted from a power spectrum of a beat frequency signal, and the output laser frequency of the second laser is locked at any preset frequency offset. The whole laser radar system uses an electrically controlled optical switch to realize the conversion between a calibration state and a detection state. In the calibration state, the laser from the second laser is selected to calibrate the frequency discrimination curve. In the detection state, the received atmospheric backwave signal light is selected for atmospheric remote sensing detection. Therefore, the calibration cost of the frequency discrimination curve is reduced, and the calibration efficiency of the frequency discrimination curve is improved on the basis of ensuring the calibration accuracy and stability of the frequency discrimination curve.