305 results about "Absorption cell" patented technology

An NDIR spectrometer based on the use of wavelength specific lamp sources, whose emission spectrum consists of discrete, narrow lines characteristic of the isotope present in the lamp, and which it is desired to measure with the spectrometer. This allows very high intrinsic sensitivity, enabling the use of an extremely compact absorption cell with a very short path length. In addition, the source can be self-modulated, such that problems associated with external choppers are avoided. Furthermore, there is insignificant cross sensitivity between the isotopes themselves and between the isotopes and other ambient gases in the operating environment.

The present invention relates to an absorption gas analyzer for measuring a concentration of at least a component gas in a sample gas. The absorption gas analyzer comprises a main absorption cell for containing the sample gas for measurement therein. At least a narrow band emitter emits electromagnetic radiation in at least a predetermined narrow wavelength band which is transmitted through the main absorption cell. A reflecting device is disposed for reflecting the electromagnetic radiation after transmission through the main absorption cell such that the electromagnetic radiation is transmitted again therethrough. At least a detector detect the electromagnetic radiation and provide at least an intensity signal in dependence upon the concentration of the at least a component gas. The absorption gas analyzer enables simultaneous determination of concentration of a plurality of individual component gases with a high level of accuracy.

The present invention discloses a miniaturized rubidium atomic frequency standard cavity-cell system, wherein, a microwave cavity cylinder is made from high magnetic permeability material; the microwave cavity cylinder is sleeved with a heating cylinder; a pump light incident port of the heating cylinder is also provided with a convex lens which gathers and transmits rays emitted by a rubidium spectral lamp into a microwave cavity; a C field coil is directly wound on a dielectric cylinder arranged between the microwave cavity cylinder and an absorption cell; a cusp on the tail part of a light-filtering cell is concentrated at the center of a circular plane at the end of the cell; a cusp on the tail part of the absorption cell is concentrated at the edge of a circular plane at the end of the cell; a photocell and a snap-off diode are fixed on the end face of the inner wall of a cavity end cover which can be movably fixed. The present invention has no machinery regulating rod inside the cavity, uses an intracavity frequency doubling mode, adopts a cylindrical TE111 mode and a dielectric filling method to get rid of the complex structure of a magnetic shield cylinder in the prior art, and reduces the volume of the cavity-cell system. As the pump light incident port of the heating cylinder is provided with the convex lens to increase the light intensity of pump light, the performance of the cavity-cell system is guaranteed. A mobile photoelectric component is adopted for cavity frequency fine adjustment, which is convenient for debugging and cannot cause field form distortion.

The invention discloses a long-path optical absorption cell adjustable in optical path. The long-path optical absorption cell adjustable in optical path comprises an incident end and an emergent end; the incident end and the emergent end are connected and fixed by use of a metal supporting rod, can directly form an open measurement system, and can also be combined with a quartz glass chamber to form a seal structure; an incident spherical mirror adjustable by use of an inclined screw is mounted on the incident end; an incident light hole is formed in the incident spherical mirror; an emergent spherical mirror adjustable by use of a rotating shaft plate is mounted on the emergent end; an emergent light hole is formed in the emergent spherical mirror; incident light is reflected between the incident spherical mirror and the emergent spherical mirror in the absorption cell, and therefore, long optical path is realized; the light hole is rotated so that a light beam is emitted from different positions, and quasi-continuous adjustability of the long optical path is realized. The long-path optical absorption cell adjustable in optical path is simple in structure and adjustable optical path is effectively realized.

The invention discloses a three-component fire gas detector which can accurately detect the concentrations of three gas components of CO, CO2 and CH4 in a fire combustion product, and proposes a fire identification method. The three-component fire gas detector is composed of a gas absorption cell, a signal processing control module and a communication module. In the invention, gas in a protected space is extracted to the gas absorption cell; when an infrared beam in the gas absorption cell passes through a specific gas, infrared light with a specific frequency is absorbed by the specific gas; and the infrared light with specific wavelength in the infrared beam changes, which indicates that the specific gas to be detected exists in the gas, and the gas detector responds immediately to convert the variable quantity and the infrared frequency of the infrared light into an electrical signal, and finally the electrical signal is subjected to signal processing to obtain gas concentrations and types in the detector. The gas detector displays the gas concentration on an upper computer through the communication module.

The invention discloses a method for preparing methionine and recovering a by-product-carbon dioxide. The method comprises the steps that a methionine salt and carbonate mixed solution obtained by hydrolyzing methylmercapto-ethyl hydantoin with alkali is filtered through a microporous membrane, and then filtrate is delivered to a bipolar membrane electrodialysis system to be subjected to electrodialysis treatment, so that acid liquor A and alkali liquor A are obtained; the alkali liquor A is treated continuously and cyclically, and the acid liquor A is subjected to gas-liquid separation, so that gaseous carbon dioxide and acid liquor B are obtained; the acid liquor B is delivered back into the bipolar membrane electrodialysis system to be subjected to cyclic treatment till the pH value of the acid liquor B is 3.8-4.5, the reaction is completed, a methionine solution is prepared, and the methionine is prepared through concentration and crystallization of the methionine solution; the gaseous carbon dioxide is introduced into an absorption cell, and carbon dioxide on the upper portion of the absorption cell absorbs mother liquor, is subjected to membrane distillation and concentration and then is circulated back to the absorption cell; carbonate crystals are grown at the bottom of the absorption cell and guided out from the bottom of the absorption cell; and carbonate is recovered through solid-liquid separation. According to the method for preparing the methionine and recovering the by-product-carbon dioxide, the gaseous carbon dioxide is recycled, so that carbon emission is reduced, and energy resources are saved through the membrane distillation technique.

The new type nodal real-time gas densitymonitoring method and sensor has one near infrared DFB semiconductor laser and operates on the characteristic absorption of methane in the near infrared spectrum region. One monomode fiber power coupler is used in separating the laser beam into several beams led through fibers to fiber gas absorption cells in mine, and the laser beams through the absorbed gas are then led through fiber to the input optical switch. The selected signal through the calibrating cell is projected to the laser detector. By means of wavelength modulating technology and second harmonic detecting technology, the present invention realizes gas density measurement in high sensitivity, high resolution, no gas interference and fast response. Background light strength signal fitting method is adopted to eliminate the influence of light strength fluctuation on the measurement.

The invention provides a deep denitrification process for wastewater. The deep denitrification process comprises the following specific steps of: firstly, performing microwave irradiation and coagulating sedimentation on the wastewater, wherein a certain quantity of NaOH is added into the high-concentration ammonia-nitrogen wastewater to adjust the pH value of the wastewater to 11-13, and a flocculant and a coagulant are added into the wastewater at an alkaline condition to perform the coagulating sedimentation, thus obtaining supernatant liquor; secondly, introducing the supernatant liquor obtained in the first step into an air stripping tower, wherein a sprayer is arranged at the top of the air stripping tower, multiple packing layers are arranged in the middle in a tower body, after passing through the sprayer, the wastewater becomes fine flow and flows through the packing layers, an air blower introduces air into the tower through an aeration port at the bottom of the tower, the air is in contact with the fine flow on the surface of packing, and exhaust for air stripping enters an absorption cell containing waste hydrochloric acid or waste sulphuric acid absorption liquid to absorb a part of ammonia nitrogen; thirdly, performing continuous circulating ammonia sedimentation on pyrolysis products of magnesium ammonium phosphate (MAP), and after the sedimentation of the MAP, processing effluent by a biological nitrogen removal process; fourthly, performing anaerobic (A)-anoxia (4)-oxic (O) biological nitrogen removal process on the effluent in the third step; and fifthly, performing denitrification on the left less nitrogen by a denitrification biofilter and a membrane filter. Therefore, ammonia nitrogen and total nitrogen of the effluent of the processed wastewater can reach a first-level A standard in the discharge standard of pollutants for municipal wastewater treatment plants (GB18918-2002).

The invention provides a frequency-stabilized laser and frequency-stabilizing method capable of stabilizing an oscillation frequency of laser beam. A photodetector detects an optical output signal obtained when a reference laser beam transmits through an absorption cell. A third-order differential signal detector generates a third-order differential signal of the optical output signal. A first actuator varies the resonator length. A first driver drives the first actuator. A second actuator varies the resonator length. A second driver drives the second actuator. A first controller controls the first driver based on the optical output signal. A second controller controls the resonator length based on the third-order differential signal using the second actuator. The first actuator and the second actuator are used to control the resonator length to stabilize the oscillation frequency.

The invention provides a TDLAS-based detection device and method of trace CO gas concentration, and solves the problems of deviation of the measured CO gas concentration value and low reliability of measurement results in the prior art. The detection device comprises a function signal generator, a laser device, a collimator, a flowmeter, an air pump, a herriott absorption cell, a temperature sensor, a pressure sensor, a focusing lens, a photoelectric detector, a preamplifier, a digital lock-in amplifier, a microprocessor and a computer, wherein a correcting module is arranged in the microprocessor, and the correcting module is used for correcting the detected gas concentration value. The detection device and method are mainly used for real-time automatic monitoring of trace CO gas, and can effectively avoid the occurrence of death accidents of personnel by poisoning of CO gas.

The invention relates to a surface weak high-frequency microwave field strength measurement technology, and in particular relates to a device and a method for measuring high-frequency microwave field strength based on an electromagnetic induction transparent effect. The device and the method are technically characterized in that high-sensitivity and high-accuracy detection for the surface weak microwave field strength can be realized by a specially designed sample absorption cell structure, and atomic line splitting is associated with the microwave field strength by a quantum coherent effect of Rydberg state atoms, so that the measurement of the microwave field strength is traced back to the frequency standard of an atomic transition line, and the self-calibration of the device can be realized by utilizing the linear relation of the microwave field strength and the frequency standard of the atomic transition line; furthermore, due to the high-sensitivity response of high Rydberg state to the weak microwave field, the detection sensitivity of the high-frequency microwave field reaches up to 0.1mV / m and even reaches up to 10mV / m. Furthermore, the whole detection device is high in stability of structure and small in microwave turbulence.

Systems and methods of the present disclosure are directed to optics used in absorption cell spectrometers. The absorption cell includes a plurality of mirrors arranged in a manner such that a detection light traverses multiple passes through the fluid within the absorption cell. In some implementations, the detection light is reflected by the plurality of mirrors to form optical paths in more than one plane. In some implementations, the orientation of the mirrors are aligned with specific orientations to provide the desired optical path to the detection light. In one or more embodiments, an alignment apparatus can be used to pre-align the mirrors before they are placed within the absorption cell. The alignment apparatus includes an aperture plate and an adjustable mount to mount one or more mirrors. The mirrors are aligned based on reflected images on the aperture plate laser light incident on the mirrors.

A laser frequency stabilizing apparatus stabilizes an oscillation frequency of laser light by varying a resonator length on the basis of a saturated absorption line included in an optical output signal. The optical output signal is obtained by irradiating an absorption cell with the laser light. The laser frequency stabilizing apparatus includes: a light detecting section for detecting the optical output signal; a differential signal detecting section for detecting a differential signal of the optical light signal; an actuator for varying the resonator length; a drive section for driving the actuator; and a control section for controlling the drive section on the basis of the differential signal. The control section determines saturated absorption lines on the basis of an output of the differential signal, selects a specific saturated absorption line on the basis of the number of determined saturated absorption lines and a combination of the determined saturated absorption lines, and stabilizes the oscillation frequency of the laser light at the specific saturated absorption line.

The invention discloses an experiment system and an experiment method used for studying dielectric barrier discharge treatment of SF[6] gases. The experiment system comprises a gas distribution system, an SF[6] gas processing system, a parameter detection system and a tail gas processing system. The gas distribution system comprises a gas bottle, a gas pressure-reducing valve, a gas distribution instrument and a bubbler. The SF[6] gas processing system comprises a pressure regulator, a plasma power supply and a dielectric barrier discharge reactor. The parameter detection system comprises a high-voltage probe, a sampling resistor, a sampling capacitor, a coaxial cable, a single-pole double-throw switch, an oscilloscope, a fiber optical spectrometer, an optical fiber, a collimating mirror, a computer and a gas chromatograph. The tail gas processing system mainly comprises a vacuum pump, a digital display pressure vacuum meter and an alkaline hydrolysis absorption cell. According to the experiment method, preparation work such as connecting and cleaning of the experiment system is carried out; then the SF[6] gas processing system is used to process the SF[6] gasses; a parameter detection system is utilized to carry out detection of required parameters; and finally, cleaning work after the experiment is completed.

The invention relates to a method and a device for detecting multi-component gas through a semiconductor laser modulated spectrum. A temperature controller and an adjustable constant flow source are adopted for driving a semiconductor laser, a scanning signal source generates a scanning control signal and injects the scanning control signal into the temperature controller to realize continuous change of temperature, so as to drive the semiconductor laser to output laser with continuous wavelength change, wherein the output laser is divided into two paths, one path of laser and the other path of laser passing through a gas absorption cell are received by a balanced detector commonly, and the scanning signal source synchronously triggers a data acquisition card to acquire a signal output by the balanced detector and input the signal to a computer for processing, so as to obtain the multi-component detection result. According to the method and the device for detecting the multi-component gas through the semiconductor laser modulated spectrum, the range of the continuous output wavelength of the semiconductor laser is expanded and the defects of narrow range of the continuous output wavelength and single detected gas type of a current driving laser are overcome, therefore, the method and the device for detecting multiple gases simultaneously by the single semiconductor laser are provided; the multi-component gas detection cost is reduced, the detection efficiency and the detection reliability are improved, and the method and the device are used for the monitoring and detecting industry of various gases.

The invention belongs to the field of low- concentration flue gas infra-red analyzers and corresponding detection methods and provides a low-concentration flue gas infra-red analyzer which is high in both precision and reliability. The flue gas analyzer adopts the structure that a gaseous contaminant detecting unit 8 comprises an infrared light source 10 and a chopper 11 behind the infrared light source 10, as well as an absorption cell 12, a measuring gas chamber 13, a light filter 14 and a detection sensor 15 which are arranged along the light path behind the chopper 11; an absorption cell sample gas inlet 16 and an absorption cell sample gas outlet 17 are formed on the absorption cell 12; and the measuring gas chamber 13 is divided into a sample cell 20 and a reference cell 21 in the light path direction so as to measure the flue gas in a high-precision manner. According to the invention, a non-dispersion infrared monochromatic source is utilized to shine the sample gas, so as to realize quantitative and accurate analysis of the to-be-tested sample gas. The infra-red analyzer and the detection method, provided by the invention, are suitable for measuring a low-concentration NO flue gas, and can also be used for the detection of low-concentration CO, CO2 and other flue gases.

The invention discloses a gas absorption tank used in absorption spectrum determination. The gas absorption tank comprises a tank body (1), two plane reflecting mirrors, and a gas chamber. The gas chamber is positioned between the two plane reflecting mirrors. A transmission path of multiple reflected beams is adopted as a main axis. A plane cover (4) is covered on the tank body (1). A plurality of optical windows are provided on the inner wall of the gas chamber of the gas absorption tank. The optical windows are formed by light reflection surfaces of the two plane reflecting mirrors, wherein the light reflection surfaces are exposed in a gas sample. The gas chamber of the gas absorption tank comprises a sample inflow port and a sample outflow port. Light beams are subject to one or moretimes of transmission in the area between the two plane reflecting mirrors. The gas sample flows along the transmission path of the multiple reflected beams.

The present invention belongs to the technical field of gas-sensitive detection, and relates to a gas-sensitive absorption device based on a hollow optical fibre. By using the hollow property of the hollow optical fibre, when light rays are restrained in the optical fibre for transmission, the detected gas is also capable of passing through the inner part of the hollow optical fibre which can be used as a light transmitting device (an optical waveguide), as well as a light absorption device (an absorption cell). The realizing procedure is that gas flows into the hollow optical fibre via front and back seal heads; optical signals get into the hollow optical fibre via the front seal head, the optical signals spread in the hollow optical fibre and are absorbed by interaction with the detected gas; emergent lights are led into a tail fibre by a taper coupler, and transmitted to a photosensitive detecting element; and the detection of gas content can be realized by light strength change. The device of the present invention has the advantages of wide transmission wavelength range and high transmission efficiency. The device is used for displacing a gas chamber absorption device in a traditional spectrograph, so as to reduce the requirements to light source and mechanical process, and improve the detection performance of the spectrograph.

A system includes a moisture analyzer configured to detect moisture in natural gas. The moisture analyzer includes an absorption cell that encloses and conducts the natural gas. The moisture analyzer also includes a pressure control device that may reduce a pressure of the natural gas inside the absorption cell. The moisture analyzer includes a light emitting device that may transmit light through the natural gas inside the absorption cell, as well as a photodetector that may detect an intensity of the light transmitted through the natural gas and exiting the absorption cell.

An apparatus and a method for detecting a leakage of heavy water in a nuclear reactor system includes: a diode laser that generates a laser beam and injects the generated laser beam to a test sample placed in a light absorption cell; the light absorption cell accommodates a gathered test sample therein; a vacuum pump adjusts a degree of vacuum in the light absorption cell; a test sample introduction unit gathers an air test sample from a location with a high possibility of a leakage of heavy water or a light water test sample from a secondary side of a steam generator and transfers the sample to the light absorption cell; an optical detector detects the laser beam which has passed through the light absorption cell; and a microprocessor controls the operation of the diode laser, the light absorption cell, the vacuum pump, the test sample introduction unit, and the optical detector, receives a detect signal from the optical detector, and analyzes an absorption spectrum signal.

The invention relates to a signal demodulation method for a fiber grating-based near-infrared absorption type concentration sensor, belonging to the fields of sensors and measuring techniques. According to the signal demodulation method for the fiber grating-based near-infrared absorption type concentration sensor, a broadband light source (11), two optical-fiber circulators (12 and 19), a sample absorption cell (13), demodulation fiber gratings (15, 16 and 20), refractive index matching liquid (17), a tuning unit (18), two photodetectors (21 and 22), a signal processing unit (23) and an optical-fiber link are comprised. The method has the characteristics that the Bragg reflection wavelength of the demodulation fiber grating (15) is identical with the near-infrared absorption wavelength of an object to be measured, the Bragg reflection wavelengths of the fiber gratings (16 and 20) are identical but are different form the Bragg reflection wavelength of the fiber grating (15), in this way, the measurement of concentration is realized by utilizing the ingeniously designed optical-fiber link structure and in combination with the differential detection method, and at the same time, the problem that the measurement is affected due to power fluctuation of the light source is solved.

An annular multi-point reflection type photoelectric gas sensor probe is disclosed. The photoelectric gas sensor probe includes an annular multi-point reflection ring having a hollow cylinder structure. Upper and lower side surfaces of the hollow cylinder structure are provided with cover plates respectively. A cavity formed by the hollow cylinder structure and the cover plates is a gas absorptioncell accommodating gas to be detected. The center of one of the cover plates is provided with a solid cylinder reducing the total volume of the gas absorption cell. The hollow cylinder structure is provided with a light beam access opening. A parallel light transceiver module is fixedly arranged at the opening, and is used for generating parallel light, processing the parallel light and then transmitting the processed parallel light to the gas absorption cell to perform a plurality of times of reflection and then outputting the light. The annular multi-point reflection design reduces the sizeof the absorption cell of the sensor probe, increases the optical path length, greatly improves optical path stability and reliability, reduces the degree of debugging difficulty and reduces the production and processing cost.

The invention discloses a novel method for exhaust gas purification. The method comprises the following steps that 1) exhaust gas is fed into a microporous aerator 3 arranged at the bottom of an absorption cell 4 by a fan 1, is adequately diffused and then is fed to the absorption cell 4; 2) an absorption solution 6 matched with the exhaust gas is filled into the absorption cell 4; the exhaust gas passes through the microporous aerator 3, then forms tiny bubbles and enters the absorption solution 6; and the exhaust gas is diffused gradually in the absorption solution 6 from bottom to top to be absorbed fully in the absorption liquid 6 which is static relatively. The novel method for exhaust gas purification can absorb and treat exhaust gas efficiently and thoroughly, has high saturated concentration of an absorption solution and high recycle values, and overcomes the defects of high structure adopted by the existing spray absorption method, high energy consumption, low efficiency and incomplete absorption.

The invention relates to a hollow photonic crystal optical fiber gas absorption cell device and a manufacturing method thereof. The device comprises a hollow photonic crystal optical fiber, a protective sleeve, a hermetic cabin, a vacuum gauge, a vacuum valve, window glass, a coupling mirror and a regulating component. According to the device disclosed by the invention, the characteristics that the hollow photonic crystal optical fiber is flexible and bendable and gas can be filled into a fiber core are utilized, quantitative injection of gas can be realized by using the hermetic cabin, the vacuum gauge and the vacuum valve, a light beam can enter the hollow photonic crystal optical fiber by being coupled by the coupling mirror and the window glass, and sealing is performed by an optical fiber metalization and feed-through welding process. The device disclosed by the invention has the characteristics of compact and small structure, high reliability, controllable gas pressure, repeated use and high coincidence degree of the section of the light beam and the gas section. The device disclosed by the invention can be used for gas spectroscopic analysis experiments and the gas absorption cell taking the frequency of a frequency stabilized laser as reference.

The invention discloses an infrared carbon and sulfur determination analyzer, which comprises an oxidation unit, an infrared absorption unit and a detection unit. The oxidation unit comprises a combustion furnace and an oxygen source, and the combustion furnace is connected with the oxygen source; the infrared absorption unit comprises an absorption cell and an infrared light source, wherein the infrared ray generated by the infrared light source passes through the absorption cell, and the absorption cell is connected with the air outlet of the combustion furnace; and the detection unit comprises a detector and a master control board for analyzing the content of carbon and sulfur, wherein the detector can receive the infrared ray passing through the absorption cell and is connected with the master control board. The analyzer has simple structure and convenient operation, and can very accurately measure the content of carbon and sulfur in a substance.

Method and apparatus for detecting, by absorption spectroscopy, an isotopic ratio of a sample, by passing first and second laser beams of different frequencies through the sample. Two IR absorption cells are used, a first containing a reference gas of known isotopic ratio and the second containing a sample of unknown isotopic ratio. An interlacer or reflective chopper may be used so that as the laser frequencies are scanned the absorption of the sample cell and the reference cell are detected alternately. This ensures that the apparatus is continuously calibrated and rejects the baseline noise when phase sensitive detection is used.

A system includes a moisture analyzer configured to detect moisture in a process gas. The moisture analyzer includes an absorption cell that encloses and conducts the process gas. The moisture analyzer also includes a pressure control device that may reduce a pressure of the process gas inside the absorption cell. The moisture analyzer includes a light emitting device that may transmit light through the process gas inside the absorption cell, as well as a photodetector that may detect an intensity of the light transmitted through the process gas and exiting the absorption cell.

A laser frequency stabilizing device comprises a laser light producer operative to produce and emit a laser light containing a first and a second longitudinal mode light having different wavelengths; a spectrometer operative to spectrally decompose the laser light into the first longitudinal mode light and the second longitudinal mode light; a first detector operative to detect the light output signal from a absorption cell; a second and third detector operative to detect the signal intensity of the first and second longitudinal mode light; an actuator operative to change the resonant cavity length; a first drive controller operative to detect the saturated absorption signal from the light output signal detected at the first detector and control driving the actuator based on the saturated absorption signal; a second drive controller operative to control driving the actuator such that the signal intensity of the first longitudinal mode light detected at the second detector and the signal intensity of the second longitudinal mode light detected at the third detector have a ratio of a certain value; and a switcher operative to switch the control of the detector between the control by the first drive controller and the control by the second drive controller.