2735 results about "Gas detector" patented technology

The invention provides methods and apparatus for detecting radiation including x-ray photon (including gamma ray photon) and particle radiation for radiographic imaging (including conventional CT and radiation therapy portal and CT), nuclear medicine, material composition analysis, container inspection, mine detection, remediation, high energy physics, and astronomy. This invention provides novel face-on, edge-on, edge-on sub-aperture resolution (SAR), and face-on SAR scintillator detectors, designs and systems for enhanced slit and slot scan radiographic imaging suitable for medical, industrial, Homeland Security, and scientific applications. Some of these detector designs are readily extended for use as area detectors, including cross-coupled arrays, gas detectors, and Compton gamma cameras. Energy integration, photon counting, and limited energy resolution readout capabilities are described. Continuous slit and slot designs as well as sub-slit and sub-slot geometries are described, permitting the use of modular detectors.

Methods of and systems for performing leak checks of gas-phase reactor systems are disclosed. Exemplary systems include a first exhaust system coupled to a reaction chamber via a first exhaust line, a bypass line coupled to a gas supply unit and to the first exhaust system, a gas detector coupled to the bypass line via a connecting line, a connecting line valve coupled to the connecting line, and a second exhaust system coupled to the connecting line. Methods include using the second exhaust system to exhaust the connecting line to thereby remove residual gas in the connecting line that may otherwise affect the accuracy of the gas detector.

A warning system (20) includes a central control unit (CCU), and a plurality of local units (LU) connected to the central control unit (CCU). Each local unit (LU) includes a plurality of input trips (An), such as smoke detector, an earthquake detector, and gas detector, and a plurality of programmable responses, such as a bypass relay (C), a message delivered by a record / playback unit (D), an emergency light (E), and a strobe light (F). The input trips (An) also include a disconnect trip (A1), which is activated by a detector input signal (DI) sent from the central control unit (CCU), and indicates that the central control unit (CCU) has malfunctioned. The programmable responses include a warning output signal (WO) which is sent from the local unit (LU) to the central control unit (CCU) to indicate the presence of a local emergency at the local unit (LU).

A wireless location-based gas detection system and method includes a gas detector for wirelessly detecting location information associated with a hazardous gas event. The gas detector includes one or more remote gas sensors that monitor for the occurrence of a gas event and wirelessly communicates information with respect to the location of the event in association with time information to a server or location manager. A wireless communication device in association with one or more location anchor points periodically and under event conditions, transmits the location information and the gas concentration level. A location engine calculates an estimated location of the gas detector based on information received from the wireless communication device and provides the location data to the location manager. The location manager records the gas concentration level, the estimated location, and the time information and stores this information within a database. A graphical user interface is provided for visualizing the current and historical information.

A method for analyzing gas concentration using doubly resonant photoacoustic spectroscopy, and a doubly resonant photaoacoustic gas detector comprising: i) a continuous wave light beam whose wavelength coincides with an absorption wavelength of a gaseous analyte; ii) a closed path optical cavity having at least two reflective surfaces; iii) an acoustic resonator chamber contained within said optical cavity, and comprising an acoustic sensor for detecting sound waves generated by a gaseous analyte present within said chamber, the light beam passing sequentially into, through and out of said chamber, and being repeatedly reflected back and forth through said chamber, and being modulated at a frequency which is equal to or equal to one-half of an acoustic resonance frequency of said acoustic resonator chamber.

A method for analyzing gas concentration using doubly resonant photoacoustic spectroscopy, and a doubly resonant photaoacoustic gas detector comprising:i) a continuous wave light beam whose wavelength coincides with an absorption wavelength of a gaseous analyte;ii) a closed path optical cavity having at least two reflective surfaces;iii) an acoustic resonator chamber contained within said optical cavity, and comprising an acoustic sensor for detecting sound waves generated by a gaseous analyte present within said chamber, the light beam passing sequentially into, through and out of said chamber, and being repeatedly reflected back and forth through said chamber, and being modulated at a frequency which is equal to or equal to one-half of an acoustic resonance frequency of said acoustic resonator chamber.

The invention relates to a method for preparing nano-doped tin oxide sol, belonging to the technical field of semiconductor nano film preparation process. The method provided by the invention mainly uses a sol-gel method to prepare nano-doped SnO2 sol on compatible reaction condition via hydrothermal processing. In the method, tin salt is taken as main raw material, villaumite and antimony salt or two parts of antimony or two parts of villaumite in appropriate content are added as doping agent to obtain doped SnO2 sol. High temperature calcination is unnecessary in the synthesized process, and nano-doped SnO2 sol can be obtained with even grains and fine dispersivity. Spray finishing, spin coating, and dipping and drawing method can be carried out on the obtained sol to prepare nano-doped SnO2 film. The film can be applied into various fields, such as low emissivity glass, display equipment, gas sensor, transparency electrode of solar battery and the like.

The invention provides a household security system which comprises a home gateway, sensors and a zigbee wireless transceiver, wherein the zigbee wireless transceiver is used for providing information interchange between the sensors and the home gateway; the home gateway comprises a central processor and further comprises a camera interface for connecting a camera, a UART (Universal Asynchronous Receiver / Transmitter) serial port interface, an Ethernet interface, an SPI (Single Program Initiation) interface, an LCD (Liquid Crystal Display) interface and an I / O (Input / Output) interface which are arranged on the central processor; the central processor comprises a master chip s3c6410 based on an ARM11 framework and a peripheral circuit; the camera interface is a USB (Universal Serial Bus) interface capable of connecting a USB camera; the UART serial port interface is connected to a MC35iGSM module; the I / O interface is connected to a voice alarm; and the sensors comprise a fire detector, an antitheft detector and a gas detector. A complex wiring process for mounting the household security system is omitted, thereby realizing multi-point and remote transmission of security information, promoting safety and reliability as well as hidden performance of the household security system, and lowering the cost.

The related integrated on-line gas detector can continual detect the content of CO, CO2, SO2, NO, NO2, N2O, CH4, HCl, H2S, HF, O2, H2 and Cl2 in smoke gas, kiln gas and furnace gas, which comprises: a sampling probe, a back-blow valve, a pump, a dehydrator, a fine filter, a bypass valve, a check valve, a stable valve, a flowmeter, a gas analysis sensor, a controller, a signal display, a signal output interface, an operation button, a drier, a power, an outdoor case, a sampling pipe, a sample-gas pipe, and a back-blow pipe. This invention has wide application.

The present invention relates to a device for accomplishing noise reduction in a photoacoustic gas detector using a sound damping element and / or a background or reference microphone where a preferably larger external volume that acts as a sound damping element (SDE) is coupled to a smaller volume through which the gas diffuses. The coupling is accomplished in such a way that the externally generated sound waves incident upon the photoacoustic detector are adequately attenuated by the larger volume SDE without adversely affecting diffusion of the gaseous species of interest through the smaller volume for measurement by the detector. Preferably this is accomplished by coupling the larger SDE volume to the smaller gas diffusion volume by a long and thin pressure channel. Another photoacoustic detector includes a measuring system to measure the photoacoustic excitation of analyte gas entering the photoacoustic detector, a reference system to measure the effect of pressure waves in the environment, and a system for offsetting an output from the measuring system with an output from the reference system to reduce noise resulting from pressure waves in the environment in an output signal of the photoacoustic detector. The present invention also relates to a device for testing the integrity of a porous member and includes a source of pressure waves and a sensor for measuring a signal resulting from the transmittal of pressure waves from the transmitter. The signal is proportional to pressure losses through the porous member. The pressure losses through the porous member are, in turn, a measure of the degree to which the porous member has become clogged.

A self-contained radio frequency (RF) wireless communication device (100) comprising an explosion-proof housing (110), an internal electronic system for the conversion of radio wave and conducted electrical signals, and an internal antenna system located within a non-metallic portion (130) of the housing for collecting and emitting radio wave energy. The antenna system enables the wireless communication device (100) to safely collect and emit radio wave energy using one or more optimally configured antenna resonators (351), with each antenna resonator differing each other antenna resonator by at least one attribute in a group of attributes comprising: frequency response, field polarization, and wavelength spatial diversity.The present invention is a self-contained RF wireless communication device that provides data communications between two or more devices for the supervisory control and / or data acquisition of actuators, sensors, transducers, gas detectors, and other devices located in explosive hazardous locations without the need of installing one or more external antennas, one or more antenna connectors, excessive conduit connections and seals, and the like, whereby reducing system installation components count and eliminating conduit connections, furthermore reducing the probability of system-level failures caused by lower-level faults of components and conduit connections, resulting in a less expensive and safer electrical equipment installation.

Disclosed is an infrared light emitting device (A) comprising a semiconductor substrate (1), a heat insulating layer (2) having a heat conductivity sufficiently lower that that of the semiconductor substrate (1) and formed on one surface of the semiconductor substrate (1) in the thickness direction, a lamellar heating layer (3) having a heat conductivity and electrical conductivity higher than those of the heat insulating layer (2) and formed on the heat insulating layer (2), and a pair of pads (4) formed on the heating layer (3) for electrical conduction. The semiconductor substrate (1) is composed of a silicon substrate. The heat insulating layer (2) and the heating layer (3) are composed of porous silicon layers having different porosities, and the porous silicon layer for the heating layer (3) has a lower porosity than that for the heat insulating layer (2). By using such an infrared light emitting device (A) as the infrared radiation source in a gas sensor, there can be realized an infrared radiation source having a prolonged life.

Methods and systems are described for drilling a well while distinguishing circulated gas or air from pumps-off gas in a drilling fluid at downhole pressure and temperature. A well is drilled with a drilling fluid, drill string, and drill bit. Drilling fluid is pumped through the drill string, drill bit, and into an annulus between the drill string and a wellbore. The drill string comprises one or more sensors sensing a parameter indicative of circulated gas or air in the drilling fluid flowing through the drill string, one or more sensors being behind and near the drill bit. The sensors measuring gas in the drill string may be at the same level as gas detectors in the annulus. The measurements are communicated to a human-readable interface at the surface, allowing an operator to determine if pressure of the wellbore fluid is greater than formation fluid pressure.

The invention discloses an air-conditioning storage method, which comprises the following steps of: a, laying a protection pad layer on the ground; b, laying a composite membrane bottom sleeve on the protection pad layer; c, stacking the stored objects on the composite membrane bottom sleeve; d, laying a top membrane on the top of the stored object stack, and then covering a composite membrane top cover; e, thermally sealing the composite membrane bottom sleeve and the composite membrane top cover together by using a plastic envelope machine, and reserving a hole; f, connecting an exhaust fan at the reserved hole in the step e to exhaust the gas in the stack so as to make the composite membrane attach the stored objects; g, forming a small hole on the opposite side of the reserved hole of the composite membrane, and connecting a gas detector; h, filling nitrogen and / or carbon dioxide into the reserved hole in the step e, and stopping filling when the concentration of the gas measured by the gas detector reaches the preset concentration; and i, sealing all the holes by using a thermal plastic envelope machine, and finishing the storage. The air-conditioning storage method can rapidly kill various insects in the stored objects, suppress mold growth, and guarantee the quality of the stored objects.

A mobile communication device with gas detecting function can detect the quality of air and immediately transfer air condition data to some remote database. The mobile communication device comprises a mobile communication module and a gas detector. The mobile communication module further comprises a communication interface, a microprocessor, and a memory. The communication interface is used for bi-directional data-transferring. The microprocessor coupling to the communication interface is used for data processing in the mobile communication device. The memory connecting to the microprocessor is used for saving data from the microprocessor and providing data to the microprocessor.

The invention relates to an air cleaning device, in particular to the air cleaning device used in a data central apparatus room. According to the air cleaning device, a filtering method combining physical filtering and chemical filtering is adopted, and the pollutant concentration in the air is monitored by a gas sensor in real time. A central processing control unit generates a 4-20mA current signal or a 0-10V voltage signal to a controller of a draught fan according to the received pollutant concentration signal, the rotating speed of the draught fan is dynamically adjusted in real time, the central processing control unit uploads the data detected by a pollution degree detector and a temperature and humidity detector to a remote monitoring terminal through a communication interface, a temperature, humidity and corrosion level radar map is generated, the effect to the device from the pollutant is analyzed, the corrosion variation trend is tracked, the corrosion risks are grasped in advance, early corrosion warning is issued, and measures are taken in advance to remove hidden dangers. A specific filtering scheme is appointed according to the environment air to enable the air cleaning device to operate in an energy-saving and efficient mode.

An infrared gas detector includes an infrared reception member, a package configured to accommodate the infrared reception member, and an optical filter. The infrared reception member includes a plurality of thermal infrared detection elements each configured to detect infrared based on heat caused by received infrared. The thermal infrared detection elements are placed side by side. The package is provided with a window opening configured to allow the infrared reception member to receive infrared. The optical filter is attached to the package so as to cover the window opening, and includes a plurality of filter elements respectively corresponding to the plurality of the thermal infrared detection elements. Each of the filter elements includes a filter substrate made of an infrared transparent material, a transmission filter configured to transmit infrared of a selected wavelength, and a cut-off filter configured to absorb infrared of a wavelength longer than the selected wavelength. The transmission filter and the cut-off filter are formed over the filter substrate. The filter substrate is thermally coupled to the package. The transmission filters of the respective filter elements are configured to transmit infrared of the different selected wavelengths.

The invention discloses an in-situ synthesis method for a nano tin dioxide / carbon nano tube composite material, which mainly uses an inorganic tin salt, a carbon nano tube and an alkali source as raw materials. The experimental process mainly comprises the steps of precursor preparation, hydrothermal reaction, precipitate washing and drying and the like. The in-situ synthesis method for the nano tin dioxide / carbon nano tube composite material has the advantages that: a hydrothermal method is adopted to realize the in-situ deposition and the growth of the nano tin dioxide on the surface of the carbon nano tube; the obtained SnO2 nano particles have small and uniform particle size (less than 10nm), are well-crystallized, are uniformly coated on the surface of the carbon nano tube, and are tightly combined with the carbon nano tube; the composite material has potential application prospect in the aspects of a gas sensor material, an anode material of a lithium ion battery and the like. The method has no addition of any surface active agent, has simple and easily-obtained materials, simple process without pollution, short preparation period, mild reaction condition and low cost, and is suitable for large-scale production, so the method is an environment-friendly synthesis method.

The invention relates to the field of testing technique of gas sensor and discloses a system for testing calibration and reliability of gas sensor. The system comprises of inlet unit, gas flow monitor, components control unit, gas mixed cavity, vacuum testing cavity and sensor electric parameter measuring device. Gas in said inlet unit is entered in gas mixed cavity to premix under the control of gas flow monitor and components control unit, and then to vacuum testing cavity which has gas sensor to be determined, the said sensor electric parameter measuring device is connected with vacuum testing cavity to detect capacity of gas sensor to be determined in vacuum testing cavity. The present invention avoids the disadvantages of dynamic gas elements capacity testing device in existence, realizes controlling exactly consistence of gas to be measured, testing different gas and controlling exactly temperature of elements.

The invention relates to a preparation method of a spongy graphene-based stretchable gas sensor. Firstly, a spongy graphene material is prepared on nickel foam with a chemical vapor deposition method, the prepared graphene / nickel foam is immersed in an etching solution and slowly reacts, accordingly, most of nickel metal is replaced chemically, the nickel metal is turned into small nickel particles, a spongy graphene / nickel particle mixing structure is fished out of the etching solution with a seal type fishing method and then is cleaned and dried, a prestretching elastic substrate is slowly recovered to the original length or area, electrodes are prepared at two ends of the graphene / nickel particle mixing structure, and the stretchable gas sensor is obtained. The gas sensor has high conductivity and good gas sensitive characteristic, is low in cost and controllable and can realize large-area growth.

The invention relates to a gas sensor test system for dynamic and static gas distribution dual purposes, and belongs to the technical field of gas sensor test. The system comprises: a test cavity, wherein the main body of the test cavity is a stainless steel cavity; sealed cabin ports, wherein the quantity of the sealed cabin ports is 2, the sealed cabin ports are respectively arranged at two ends of the test cavity, and every sealed cabin port is matched with a sealed cabin door; a gas inlet pipeline arranged on one of the sealed cabin ports; a gas outlet pipeline arranged on the other one of the sealed cabin ports; a humiture sensor arranged in the test cavity; a liquid injection window arranged on the sealed cabin door provided with the gas outlet pipeline and used for injecting a liquid to the test cavity; and a heating platform arranged in the test cavity, wherein the liquid injection window cooperates with the heating platform to heat the injected liquid in order to vaporize the liquid. The system can realize simulation of dynamic gas environment and static gas environment, and also can realize performance calibration and test of a gas sensor in different gas environments.

The invention discloses a preparation method of a porous silicon-based tungsten trioxide nanorod composite-structure gas sensor element. A porous silicon layer is prepared on a polished surface of a P-type single-side-polished monocrystalline wafer by double-channel electrochemical corrosion; tungsten oxide nanorods are grown in situ on porous silicon by hydrothermal process, so that composite-structure porous silicon-based tungsten trioxide nanorods are obtained; two platinum electrodes are deposited on the surface of the wafer by magnetron sputtering. The novel porous silicon-based tungsten trioxide nanorod composite-structure gas sensor element which has excellent gas-sensitiveness features, such as simplicity in preparation process, ease of control, capability of detecting nitride oxide gas at the room temperature and high flexibility, is provided.

The invention discloses a system and a method for detecting milk freshness based on an electronic nose and aims to overcome the defects in quick detection of the raw milk freshness. The system comprises a flavor fingerprint information acquisition module, a signal preprocessing module, a character extracting and screening module and a pattern recognition module, wherein the flavor fingerprint information acquisition module is used for reading voltage signals responding to gas of a gas sensitive array into an internal memorizer in a digital manner, implementing real-time digital display and waveform display of the read data, and storing and recycling the displayed data; the signal preprocessing module is used for preprocessing the original signals by using a filter function, for example, removing noise of the original signals and extracting basic signals; the characteristic extracting and screening module is used for extracting characteristics of the filtered and de-noised signals and screening the characteristics according to a principal component analysis method; the pattern recognition module is used for training and identifying the detected samples according to a pattern recognition algorithm. The system and the method are used for quickly detecting the raw milk freshness based on the electronic nose and have guiding significance to control of flavor and quality of milk products. Compared with the conventional method, the method provided by the invention is more efficient and convenient, faster, and lower in manpower cost.

The invention provides a method for testing nuclear pollution and chemical pollution with a remote-controlled movable robot, which aims at the problem of automatic testing under the circumstances of nuclear pollution and chemical pollution. The invention has the following main points: a remote-controlled robot enters a polluted site under the remote wireless control by the operator and transmits the information of an accident site back to a local operation platform through wireless transmission; the movable robot is provided with a nuclear detector and an instrument cabinet; a chemical gas detector, a camera and an illuminating lamp are arranged in the instrument cabinet, and a camera captures the images of the indication panel of a chemical gas detector and transmits the images back to the local operation platform; the pollution source is removed or sampled by mechanical arms after being found; and the movable robot is provided with a GPS navigator to position the pollution source. The invention has the advantages of zero casualty, flexible replacement of instruments in the instrument cabinet and the like, and can be used in highly dangerous accident sites with nuclear pollution and chemical leakage, which can not be detected with normal means.

A process for synthesizing the cuprous oxide nanoballs includes such steps as dissolving the Cu salt in water-soluble organic solvent, sequentially adding non-ionic surfactant and strong reducer, and reflux at 70-90 deg.C in an open system to obtain quasi-single-dispersed cuprous oxide nanoballs. Said cuprous oxide can be self-assembled on silicon chip or electrically conductive glass to form 2D or 3D structure for meeting the requirement of solar cell or microelectronic device.

The related gas sensor for fuel cell comprises: based on traditional device, designing a cell core expansion hole and an air hole, using gel electrolyte instead of common liquid, adding a constant moisture device for sensor. It also uses the sensor to prepare a gas detector with self test and adjust function and free to environment effect and calibration gas source. This invention overcomes defects in prior art.