2727 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 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.

An electrical receptacle provide outlets and a cavity for receiving an insert. The insert connects to the electrical main through the receptacle and can provide additional functionality through the insert including emergency lighting, night lighting, gas detectors and charging connections.

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 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.

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.

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 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.