Abstract: Method and apparatus for precision non-destructive non-contact control of super small differences of pressure, which is used for non-destructive control of tightness of various products regardless of the method of sealing and the state of the internal volume of products, with the apparatus consisting of a body of the control unit of the device, working and control units, sensitive membrane, transparent window of the control unit, connecting pipes of the control and working chambers, electronic speckle interferometer, the base that is isolated from the vibration, and the electronic processing unit for monitoring results and presenting results on the display. The bending of the membrane characterizes the quality of sealing of the investigated object and is determined by the laser method of non-contact electronic speckle interferometry.

Abstract: A method of analyzing a gas specimen mixture includes measuring the concentrations of inert components in the gas specimen mixture and the pressure and temperature of the gas specimen mixture. A number of sample gas mixtures are generated with varying percentages of hydrocarbon gases, each including the measured inert component concentrations. For each generated sample gas mixture, the method includes calculating the speed of sound therein based on the measured pressure and temperature and the particular percentages of hydrocarbon gases therein, measuring the speed of sound in the gas specimen mixture, and iteratively comparing the measured speed of sound with the calculated speed of sound in different sample gas mixtures until convergence for a particular sample gas mixture. The molecular weight of the particular sample gas mixture is calculated, and set the molecular weight of the gas specimen mixture to the calculated molecular weight.

Abstract: A gas specimen mixture analysis system includes at least one sensor for measuring the concentrations of inert components in the gas specimen mixture, a pressure sensor for measuring the pressure of the gas specimen mixture, and a temperature sensor for measuring the temperature of the gas specimen mixture. A subsystem measures the speed of sound in the gas specimen mixture, and a processing subsystem, responsive to the at least one inert component sensor, the pressure sensor, the temperature sensor, and the subsystem for measuring the speed of sound, is configured to generate a number of sample gas mixtures with varying percentages of hydrocarbon gases, each including the measured inert component concentrations.

Abstract: A filter assembly for use with compressor assemblies such as oxygen concentrators, ventilators and other breathing apparatus including a compartmented housing member having at least one inlet opening, an outlet opening, a filter member, and an adjustment member associated with the at least one outlet opening for varying the size of the at least one outlet opening for adjusting the amount of ambient air entering the filter assembly.

Abstract: A method for sensing gas composition and gas pressure, based on the thermal constants of a variable electrical resistor, is presented. The method for sensing gas composition and pressure includes monitoring a variable electrical resistor whose dynamic thermal response is determined by the thermal conductivity and thermal capacity of the surrounding gas of a given atmospheric environment. In the thermal domain, the sensor has a low-pass characteristic, whose phase delay is determined by the thermodynamic characteristics of the surrounding gas such as composition and pressure. The method can be used for sensing gas composition and can also be used for sensing gas pressure.

Abstract: A method to measure the concentration of a constituent element in a gas sample contained in an analyzer. A sample cell of a detector has an inlet and an outlet. The outlet of the sample cell is sealed. A predetermined mass of a gas sample is received through the inlet into the sample cell over a predetermined pressurization period until substantially the entire mass of the gas sample contained in the analyzer is contained within the sample cell. The gas sample is pressurized to a predetermined pressure over the pressurization period. A concentration of a constituent element in the pressurized gas sample is determined.

Abstract: Gas analyzer systems and methods for measuring concentrations of gasses and in particular dry mole fraction of components of a gas. The systems and method allow for rapid measurement of the gas density and/or dry mole fraction of gases for a number of environmental monitoring applications, including high speed flux measurements. A novel coupling design allows for tool-free removal of a cell enclosing a flow path to enable in field cleaning of optical components.

Abstract: A fuel tank safety system includes an ullage cooling assembly and a system controller. The ullage cooling assembly includes a compressor configured to extract a quantity of ullage gas from the fuel tank, a heat exchanger coupled in flow communication downstream of the compressor, wherein the heat exchanger is configured to receive the quantity of ullage gas from the compressor and reduce a temperature of the ullage gas. The ullage cooling assembly includes a turbine coupled in flow communication downstream of the heat exchanger, wherein the turbine is configured to further reduce the temperature of the ullage gas and facilitate channeling the ullage gas to the fuel tank. The system controller is operatively coupled to the ullage cooling assembly and is configured to transmit to the ullage cooling assembly one of a start signal to activate the ullage cooling assembly or a stop signal to deactivate the ullage cooling assembly.

Abstract: A photo, acoustic detector (200) for detecting a concentration of a sample in a sample mixture. The photo acoustic detector (200) comprises a light source (101 ) for producing a light beam for exciting molecules of the sample and a light modulator (102) for modulating the light beam for generating pressure variations in the sample mixture, an amplitude of the pressure variations being a measure of the concentration. The photo acoustic detector (200) further comprises a detector element (103) for converting the pressure variations into a detector current and a processing section (106) for processing the detector current to generate an output signal representing the concentration.

Abstract: Methods and devices for detecting photoresist coating failures are disclosed. A disclosed method to detect a photoresist coating failure on a semiconductor wafer comprises: loading a photoresist coated wafer on a notch position check block; rotating the coated wafer; detecting the position of a notch in the wafer; blowing air toward the surface of the wafer with at least one air nozzle located over the rotating wafer; detecting an amount of the air blown from the at least one air nozzle; and generating a coating failure signal if a variation in the amount of air blown from the at least one air nozzle is indicative of a photoresist coating failure.

Abstract: A system and method for controlling the bleed valve in an anode recirculation loop of a fuel cell system. The system uses a model to determine the concentration of hydrogen in the recirculated gas by calculating the volume flow of the recirculated gas through a fuel cell stack, a pressure drop across the anode inlet and outlet of the stack, and the density of the recirculated gas, and using a measured temperature of the recirculated gas and a measured pressure drop across a recirculation pump.

Abstract: A gate valve corresponding to the sealing structure seals an opening of a plasma generation chamber and includes a valve body, a valve stem, and ring-shaped first and second sealing members that seal a gap between the valve body and the plasma generation chamber. The first ring-shaped sealing member is on the side of the plasma generation chamber and is exposed to a plasma atmosphere. The first and second ring-shaped sealing members do not contact each other, that is, a gap is formed therebetween. A plurality of gas grooves are arranged in the length direction of the first ring-shaped sealing member. The gas grooves are formed by cutting the valve body in a direction almost perpendicular to the length direction of the first ring-shaped sealing member, and the gap is in communication with the plasma generation chamber via the gas grooves. A gas injection passage 14 for injecting a gas into the gap is formed in the wall of the plasma generation chamber.

Abstract: A pencil-type glow plug for a self-igniting internal combustion engine is described. The pencil-type glow plug includes a plug body in which a combustion chamber pressure sensor is integrated, and a bar-shaped heating element that protrudes out from the plug body at one end, into the combustion chamber of the internal combustion engine. A force-measuring element of the combustion chamber pressure sensor is accommodated behind the heating element, which moves axially under the influence of force. The force-measuring element is sealed against combustion chamber gases by a steel diaphragm made of a stainless precipitation-hardened maraging steel.

Abstract: A system is disclosed to isolate an environmental chamber of an immersion lithographic apparatus, to which an immersion fluid comprising liquid, is provided from an external environment. Further, there is disclosed a system for measuring flow rate and/or vapor concentration of a gas using a transducer to send and/or receive an acoustic signal.

Abstract: A method and apparatus are provided for maintaining pressure inside a closed chamber equal to the changing outside pressure, detecting leaks in the plumbing (i.e., air handling system) of a trace gas flux measurement system, and estimating the kinetic volume, e.g., of such a system.

Abstract: A method and an article of an electrically conductive ceramic interconnect bonded to a compatible ceramic housing for an oxygen partial pressure sensor system. The interconnect includes a LaxSryAlzMn1?zO3 (LSAM) having a stoichiometry enabling good electrical conductivity at high temperatures and the LSAM also bonded to a yttria stabilized zirconia forming a stable and durable seal.

Abstract: Guidelines for designing lenses or systems for aerodynamic focusing of nanoparticle or cluster beams. The design process may involve obtaining a relationship between particle size, operating pressure and aperture size, and selecting the operating pressure to provide continuum flow of an aerosol beam through the aerodynamic lens. Particles having diameters less than 30 nanometer may be focused. Simulation techniques for evaluating designed lenses are also disclosed.

Abstract: Provided is a partial pressure measuring method and a partial pressure measuring apparatus by which a partial pressure distribution is easily measured in a vacuum chamber. The partial pressure measuring method and the partial pressure measuring apparatus includes: moving a local plasma source dedicated to partial pressure measuring provided in the vacuum chamber, to a location at which the measuring is to be performed; and measuring a partial pressure distribution in the vacuum chamber, by receiving emission of plasma generated by the local plasma source through a window which is formed in a wall part of the vacuum chamber and through which the emission passes, and thereby performing emission spectral analysis on intensity of the emission.

Abstract: Apparatus and methods for testing the hydrogen-gas compatibilities, hydrogen-gas embrittlement susceptibilities, hydrogen-gas containment performances, and/or the hydrogen-gas pressure-cycling durabilities, of hollow enclosures (“test specimens”), with single-layer, double-layer, or multi-layer walls, composed of various barrier materials, are disclosed. Barrier materials include but are not limited to: carbon steel, stainless steel, copper, aluminum, a polymeric material (e.g., high-density polyethylene), and a liquid material (e.g., water, or an aqueous solution). The test gas is either high-purity hydrogen or a hydrogen-bearing gas mixture (e.g., hydrogen gas mixed with methane/natural gas and/or biomethane). A key piece of the testing equipment is an enclosure that surrounds the test specimen. Fabricated from high-strength, porous solid material (e.g.

Abstract: A surface acoustic wave based CO2 sensor using carbon nanotubes as the sensitive layer fabricated by combining surface acoustic wave (SAW) devices and nanotechnology. The device structure consists of the gas sensitive material between the input and output interdigital transducers (IDTs) of a SAW device. The CO2 gas gets adsorbed on nanotubes when the carbon nanotube based SAW sensor is exposed to CO2 at room temperature and/or at elevated temperature, which in turn changes conductivity of the carbon nanotube. This conductivity change will affect the velocity of the SAW traveling across the nanotubes and will give a frequency change which corresponds to the percentage of the CO2 molecules adsorbed by the nanotubes.

Abstract: A nano-particle containing apparatus, a nano-particle detection system and a method are disclosed. The nano-particle containing apparatus includes a casing, an air extracting device, a pressure device and a measuring instrument. The casing has a containing space for disposing a plurality of nano-particles. An internal wall surface of the casing has active self-cleaning function. The pressure control device controls the pressure status of the containing space. The active self-clean function is that nano-particles adhered to the internal surface wall are removed into the containing space. The nano-particles then are pumped by the air extracting device from the containing space. The measuring instrument then detects the status of an object affected by the nano-particles after the object is delivered into the containing space.

Abstract: The invention relates to a biogas measuring device comprising a bioreactor (9); a gas volume measuring appliance (2) which is connected to the bioreactor (9) in a communicating manner by means of a gas line (11) for biogas; a stirring machine (10) guided in the bioreactor in a gas-tight manner, and a measurement, control and evaluation unit for controlling the biogas measuring device and determining the gas volume (V) produced in the bioreactor according to gas volumes (?V) of consecutive measuring cycles, measured by means of the gas volume measuring appliance (2).

Abstract: The invention is directed to a pressure sensor device for sensing decompression in a compartment, such as an aircraft cockpit, and causing a compartment door to be free to open substantially simultaneously in response to the decompression. The pressure sensor comprises a first pressure port and a second pressure port where both pressure ports are open to the compartment, and the second pressure port has a greater flow restriction than the first pressure port, When the pressure sensor is actuated by a difference in pressure between the first pressure port and the second pressure port caused by decompression in the compartment, the pressure sensor sends a signal either via direct wired in series or to a controller to enable movement of a compartment door in response to the decompression.

Abstract: The plasma processing apparatus relating to the present invention is provided with a process chamber, a pressure measuring unit for measuring the pressure inside of the process chamber and a pump for exhausting a gas in the process chamber. A pressure control valve for maintaining the pressure inside of the process chamber to a predetermined pressure by regulating an opening based on a measured value of the pressure measuring unit is provided between the pump and the process chamber. An exhaust capacity controller sets up the exhaust capacity in a state that the variation of the opening of the pressure control valve in response to the pressure fluctuation inside of the process chamber is large. A computing unit detects very small pressure fluctuation based on the variation of the opening of the pressure control valve. In results, enabling reliable detection of a very small gas flow fluctuation and pressure fluctuation by a less expensive method independent of process conditions.

Abstract: A detector for monitoring the low levels of differential pressures and the rate of mass flow rate of gas (air, e.g.) in a duct. The sensor's temperature is maintained at a constant gradient above temperature of the flowing gas, typically 4-7° C. higher. The detector consists of two thermally decoupled sensors—one is the air temperature sensor and the other is a temperature sensor coupled to a heater. The sensors are connected to an electronic servo circuit that controls electric power supplied to the heater. The sensors are positioned outside of the air duct and coupled to the duct via a relatively thin sensing tube protruding inside the duct. The end of the tube has an opening facing downstream of the gas flow, thus being exposed to a static gas pressure.

Abstract: A pressure actuated electrical switch and indicator to indicate to a user that a filter vacuum cleaner requires cleaning or replacing. In a first embodiment, the pressure actuated electrical switch measures the pressure present between the filter media and the flow inducing device to determine whether a minimum absolute pressure threshold has been exceeded. The pressure actuated switch has a chamber with two electrical leads that are connected when the pressure in the vacuum cleaner raises above a predetermined level. A tube from the chamber to the vacuum cleaner housing draws a conductive part into contact with both leads. In additional embodiments, the pressure measure is the difference in air pressure above and below the filter media, or the difference in air pressure between the pressure in the air stream between the filter media and the flow inducing source, and the ambient air pressure.

Abstract: An air supply system for a clean room with a critical machine. An intake duct connects the exterior of the clean room to a make-up air unit, and is configured to transport external air into the make-up air unit. A first air duct connects the make-up air unit to an air conditioning cabinet including a first chemical filter, and is configured to transport the air flowing through the make-up air unit into the air conditioning cabinet. The first chemical filter removes airborne molecular contamination from the air transported into the air conditioning cabinet. A second air duct connects the air conditioning cabinet to the critical machine, and is configured to transport the air flowing through the first chemical filter of the air conditioning cabinet into the critical machine. An exhaust duct connects the critical machine to the exterior of the clean room, discharging waste gas produced in the critical machine.

Abstract: A deposition apparatus supplies a reactive gas obtained by vaporizing a liquid material at a vaporizer 30 into a chamber 10 via a processing-gas pipe 40 and forms a thin film on a semiconductor wafer W due to a thermal decomposition of the reactive gas. The deposition apparatus is provided, in the processing-gas pipe 40, with a crystal gauge 51 detecting a pressure Pq under the influence of mist in the reactive gas and a capacitance manometer 52 detecting a pressure Pg under no influence of the mist. The apparatus further includes a gasification monitor 50 detecting a quantity of mist in the reactive gas on the basis of a difference ?P between the pressure Pq and the pressure Pg measured by the crystal gauge 51 and the capacitance manometer 52 in order to prevent deposition defects due to the mist in the reactive gas.

Abstract: A combination vacuum gauge provides simultaneous absolute and differential pressure measurements over a wide range of pressures ranging from atmospheric pressures to ultrahigh vacuum by processing the readings from an absolute high vacuum gauge (e.g., an ionization gauge and/or a heat-loss sensor), a differential low vacuum gauge providing a differential relative to ambient pressure (e.g., a diaphragm sensor), and a barometric absolute pressure sensor exposed to the ambient atmosphere outside the measurement region. The barometric absolute pressure sensor reading is used to convert the differential vacuum gauge reading from uncalibrated differential pressure to calibrated absolute pressure.

Abstract: Screening of items for the presence of contaminants, such as explosives residue, is accomplished by subjecting an item loaded into a pressure chamber to a pressure substantially in excess of atmospheric pressure conditions and rapidly decompressing the item to the ambient atmospheric pressure. The rapid decompression serves to scavenge vapors and particles from the exterior and interior of the item and any objects it contains. A sample of the vapors and particles removed from the item by the rapid decompression is sampled and is tested to determine whether a predetermined contaminant is present in the sample. Depending on the types of contaminants for which the sample is tested, it is possible to detect whether explosives, biological or chemical agents, and/or narcotics residues are present on or in the item being screened.

Abstract: This apparatus and method allows collection concentrated sample of content in shipping packages without unsealing the package by forcing airflow via existing hidden gaps or, if necessary, creating one by a small incision. The air is injected into the hidden gaps by either probe or socket device to disturb and agitate contents inside the package, causing the contents to loosen and blend particulates on the surface into the air stream. Airborne particles are channeled into detection device, where the particulates are concentrated. Display and warning apparatus receives and records the analysis results from detection device. If the analysis finds that predetermined selection and sensitivity criteria for target hazard or contraband is met, then the warning apparatus initiates appropriate alert protocols.

Abstract: A dust collection apparatus includes a container and a suction pump that sucks dust and transports it into the container. A filter is provided on a side surface of the container. This filter passes air but prevents passage of the dust in the container. A pressure detector detects an internal pressure of the container. The internal pressure of the container fluctuates due to a variation in an effective area of the filter for allowing the air to pass according to the dust collected and accumulated in the container. A dust accumulating quantity calculator which determines a quantity of the dust in the container based on the pressure detected.

Abstract: Screening of items for the presence of contaminants, such as explosives residue, is accomplished by subjecting an item loaded into a pressure chamber to a pressure substantially in excess of atmospheric pressure conditions and rapidly decompressing the item to the ambient atmospheric pressure. The rapid decompression serves to scavenge vapors and particles from the exterior and interior of the item and any objects it contains. A sample of the vapors and particles removed from the item by the rapid decompression is sampled and is tested to determine whether a predetermined contaminant is present in the sample. Depending on the types of contaminants for which the sample is tested, it is possible to detect whether explosives, biological or chemical agents, and/or narcotics residues are present on or in the item being screened.

Abstract: An electrical measurement device is described, with a measurement input, an integrated sensor, a measurement and evaluation circuit, and a measured value display, and several measured value outputs. The electrical measurement device enables not only one measured value or several measured values to be determined, but makes it possible to display and process the determined measured values depending on other values such as comparison values and setpoints. An influencing input acts on the measurement and evaluation circuit and is the connecting point for the electrical measurement device to which or via which an influencing value can be applied or input. Therefore, a value with which the measured value can be influenced in the broadest sense is applied.

Abstract: A system for the collection of near real time confirmation samples is provided to quickly eliminate false positive alarms by confirming the presence or absence of a chemical agent when a monitor operating in near real time to detect the presence of that chemical agent generates an alarm. The confirmation sampling system is synchronized with the near real time monitor and the confirmation sampler and monitor draw common samples of the atmosphere of concern. In the event that the monitor generates an alarm, the confirmation sampler preserves the sample taken contemporaneously with the alarm event for separate analysis, and also takes and preserves one or more follow-on samples.

Abstract: An airbag system for a motor vehicle has an airbag that is deployed upon inflation with a gas from a folded state into the vehicle interior. An inflation device supplies gas for inflating the airbag. A sensing device senses deployment of the airbag to the effect that the temporal and spatial sequence involved in opening the folds of the airbag is detected. A control device controls the inflation process as a function of deployment sensing.

Abstract: The present invention relates to a pressure housing for in-water pressure based systems and to a method for improving the life of the transducers and electronics of underwater systems by maintaining a humidity-free and clean environment around them by avoiding the entry of humidity, dust, or any suspended particles in the air during occasional data offloading and battery replacement in a humid and dust-laden field station; improving the ease of closing and opening of the pressure housing by the use of a novel arrangement thereby avoiding the use of conventionally employed cumbersome protruding and corrosion-prone locking devices such as screws, bolts, or clamps; and implementing reliable transmission of water pressure to the pressure port of the transducer, simultaneously minimizing the errors arising from dynamic pressure effects, preventing its chemical corrosion from saline water, and arresting bio-fouling in the vicinity of the pressure inlet.

Abstract: The invention relates to a method and to apparatus for thermodynamic analysis of a mixture of fluids, in which the volume of a sample of a given quantity of said mixture is caused to vary step by step and in monotonic manner, and the pressure of the sample is read at each step, the sample being stirred at each step so as to hasten the mixture reaching thermodynamic equilibrium. According to the invention, the sample is stirred by applying ultrasound to said sample by means of transducer (20). The sample can be contained in a bag (19) of flexible material immersed together with the transducer in a control fluid inside a rigid container (10). The invention can be used to determine the bubble point of a mixture of hydrocarbons.

Abstract: A method and apparatus for monitoring, controlling, recording, and transmitting operational parameters of an aquifer test, municipal well, dewatering project, pump and treat remediation project, or similar activity is presented. Water from a water source, typically a well, is directed through a flow control and monitoring assembly containing sensors to measure well parameters. Sensor readings are sent to a computing device for processing. Discrepancies are detected and operational parameters adjusted to avoid discrepancy-related failures. On-site and off-site personnel interface with the system through a man-machine interface or telephonic communication means, respectively. Performance and efficiency are determined in terms of drawdown, yield, rate of flow, residual drawdown, and specific capacity.

Abstract: In automated reprocessing system (B), a leak detection system (10) evaluates the integrity of an endoscope (A), having an internal passage (66). The leak detection system includes an interior chamber (42) which is connected to the internal passage by quick connects (18, 20). A source of compressed air (22) pressurizes the chamber and internal passage to a suitable test pressure. A pressure sensor (50) and a temperature sensor (54) detect the pressure and temperature within the chamber and hence in the endoscope passage. Pressure and temperature measurements made over time are used to determine changes in the gas volume, indicative of whether leaks are present in the endoscope. If the endoscope is determined to be free of leaks, the endoscope is washed and microbially decontaminated in the reprocessing system.

Abstract: The system includes an access assembly for communicating with the gas filled insulating units, flexible electrodes for insertion through the access assembly to the gas and for sensing the concentration of the gas, and a meter for measuring and displaying the concentration of the gas that is sensed through the electrodes.

Abstract: The invention is a method for determining the Joule-Thomson coefficient of a fluid, expressing the temperature variation in relation to a pressure variation thereof. The fluid is injected at a determined injection temperature into a thin tube (8) (preferably a capillary tube in order to obtain a high pressure drop with reasonable flow rates) which contains a temperature detector (TC1) leading to a pressure drop for the fluid. The temperature variation of the fluid in relation to the injection temperature is measured by means of this temperature detector. The pressure drop undergone by the fluid in tube (8), due to the presence of this temperature detector, is also measured and the Joule-Thomson coefficient is calculated by combination of measurements of the pressure drop and of the temperature variation of the fluid. The method can be applied notably in the field of hydrocarbon production, more particularly hydrocarbons coming from high-pressure and high-temperature reservoirs and in gas lines.

Abstract: A measuring device is proposed to measure the gas pressure of an atmosphere, whereby the measuring device is provided with a sensor to measure the pressure located in the interior of a housing which encloses the sensor. In addition a unit to control the measuring device and to evaluate the signals as well as a supply unit are installed in this housing. The housing itself is sealed off against the surrounding atmosphere and is provided with contacts on the housing for the exchange of data between the measuring device and a unit for the evaluation of measured values connected to it. The contacts are provided at the same time to ensure that the unit for the evaluation of the signal of the pressure sensor can be supplied with control signals from outside the housing.

Abstract: An air filter cleanness gauge is provided. The gauge in a preferred embodiment includes a transparent cover. The housing has a first opening for fluid communication with the atmosphere and a second opening having fluid communication with a fluid source exposed to a filter. A vane is pivotally connected within the housing and provides a pressure boundary between the first and second openings. Movement of the vane indicates a change in pressure differential between the atmosphere and the fluid source, thereby indicating a need to change the air filter.