Abstract: Sensing elements, sensor systems and methods for determining the concentration of oxygen and oxygen-related analytes in a medium are provided. The sensing element comprises a solid polymeric matrix material that is permeable to oxygen or an oxygen related analyte and an indicator that is covalently bonded to the solid polymeric matrix material. The indicator is a luminescent platinum group metal polyaromatic chelate complex capable of having its luminescence quenched by the presence of oxygen. The polyaromatic complex comprises three ligands, at least one of which is a bidentate diphenylphenanthroline. The polyaromatic complex is distributed substantially homogenously throughout the matrix material and is covalently bonded to the matrix material via a linker arm. The linker arm is attached to a phenyl group of a diphenylphenanthroline ligand and to the backbone of the polymeric matrix material.

Abstract: A sample injector valve capable of introducing multiple samples of material into multiple liquid or gas streams is provided. Such a valve is particularly useful for injecting multiple samples under pressure into a combinatorial chemistry system with moving streams of fluid, such as a parallel pressure reactor or a rapid flow analysis system using multi-channel or parallel chromatography and related techniques. The valve is further capable of functioning on a small scale with automatic sampling equipment.

Abstract: The present invention provides a method of quickly identifying bioaerosols by class, even if the subject bioaerosol has not been previously encountered. The method begins by collecting laser ablation mass spectra from known particles. The spectra are correlated with the known particles, including the species of particle and the classification (e.g., bacteria). The spectra can then be used to train a neural network, for example using genetic algorithm-based training, to recognize each spectra and to recognize characteristics of the classifications. The spectra can also be used in a multivariate patch algorithm. Laser ablation mass specta from unknown particles can be presented as inputs to the trained neural net for identification as to classification. The description below first describes suitable intelligent algorithms and multivariate patch algorithms, then presents an example of the present invention including results.

Abstract: CO exposure is a serious public health problem in the U.S., causing both morbidity and mortality (lifetime mortality risk approximately 10−4). Sparse data from population-based CO exposure assessments indicate that approximately 10% of the U.S. population is exposed to CO above the National Ambient Air Quality Standard. No CO exposure measurement technology is available for affordable population-based CO exposure assessment studies. Two CO measuring devices, an occupational CO dosimeter (LOCD) and an indoor air quality (IAQ) passive sampler, were designed, developed, and tested both in the laboratories and field. Time-weighted-average CO exposure of the compact diffusion tube sampler containing a selective and non-regenerative palladium-molybdenum based CO sensor is quantified by using a simple spectrophotometer. Both devices are capable of measuring CO exposure precisely with relative standard deviation of less than 20% and with bias of less than 10%.

Abstract: An effluent monitoring apparatus 10 comprising an energizing cell 22 adapted to receive an effluent, a gas energizer 17 that is capable of energizing the effluent in the cell 22 thereby emitting a radiation, a radiation permeable window 27 that is spaced apart from the wall 36 of the 22 cell by a distance d that is sufficiently high to reduce a deposition of effluent residue from the energized gas on the window 27, and a detector 26 to detect the radiation.

Abstract: A gas chromatography system having a computer-controlled pressure controller that delivers pressurized pulses to a column junction point of two series-coupled columns having different stationary-phase chemistries and a method of using the same. Each pressurized pulse causes a differential change in the carrier gas velocities in the two columns, which lasts for the duration of the pressurized pulse. Whereby, the pressurized pulse selectively increases the separation of a component pair that exhibits separation at the exit of the first column, but otherwise co-elutes from the column ensemble.

Abstract: A detector for detecting vapors emitted from energetic compounds includes a housing, a pump and a sensing assembly. The housing has an inlet, an outlet and an enclosed sensing volume there between. The pump communicates with the housing for moving a carrier gas sequentially through the enclosed sensing volume at a predetermined flow rate. The sensing assembly senses the vapors of the energetic compound delivered by the carrier gas as the carrier gas passes through the housing. The sensing assembly includes a sensing unit constructed of an amplifying fluorescent polymer, a source of excitation, a light detector, and a convertor assembly.

Abstract: A method and system for determining a concentration level of NOx in an exhaust stream from a combustion source. The method comprises capturing sample gas from the exhaust stream using a sampling device. NO2 in the sample gas is converted to NO by passing the sample gas through a catalytic NO2 converter. The method also comprises removing water from the sample gas by passing the sample gas through a dryer and determining a sample gas NO concentration level. The step of converting NO2 is performed at a temperature above the dew point temperature of the sample gas.

Abstract: Chemical reactions are monitored by a cantilever sensing arrangement in which the reaction is transduced into mechanical responses that may be detected with a high degree of sensitivity. Projecting fingers interdigitate and, based on the extent of reaction, bend in a manner that may be detected optically.

Abstract: A method and apparatus for determining ammoniacal species concentration in a gas sample. In one embodiment, trace concentration of ammonia in an air sample is determined by monitoring emission intensity from an excited radical species (NH*), which is produced in a reaction between ammonia and fluorine. The observed emission intensity is compared with calibration data obtained from previously analyzed gas samples containing ammonia. The method and apparatus can also be adapted to detect ammoniacal species concentration in other NH-containing gas samples.

Abstract: The optical sensor contains an optical waveguide (1) with a substrate (104), waveguiding material (105), a cover medium (106) and a waveguide grating structure (101-103). By means of a light source (2), light can be emitted to the waveguide grating structure (101-103) from the substrate side and/or from the cover medium side. (101-103). With means of detection (11), at least two differing light proportions (7-10) radiated from the waveguide (1) can be detected. For carrying out a measurement, the waveguide can be immovably fixed relative to the light source (2) and the means of detection (11). The waveguide grating structure (101-103) itself consists of one or several waveguide grating structure units (101-103), which if so required can be equipped with (bio-)chemo-sensitive layers. The sensor permits the generation of absolute measuring signals.

Abstract: Methods and devices are described for rapidly and simultaneously detecting, quantifying, and imaging gases, odors, malodors, volatiles and semi-volatiles using gas chromatography coupled with arrays of organic conducting polymers. The methods utilize changes in the polymer conductivity as a function of temperature to detect volatile organic molecules upon adsorption to the polymers. By raising the sensor temperature, adsorbed materials are further desorbed. This eliminates the fundamental problems of sensor fouling resulting from exposure to sulfur, nitrogen or ketone containing malodors. In a second embodiment, the resulting gas effluents from the sensor array are mixed with air, oxygen or hydrogen to produce a cloud of luminance that is detected by a charge-coupled device.

Abstract: Disclosed herein is a nebulizer capable of performing spraying over a wide flow-rate range from a low flow rate to a high flow rate stably and with high efficiency. Further, the present invention provides a supersonic nebulizer capable of improving the efficiency of spraying by a supersonic region spray gas, and a supersonic array nebulizer wherein a plurality of spray units are placed in array form.

Abstract: Detection of an evolving or diffusing gaseous substance emanating from an irradiated or thermolyzed layer of polymeric composition in semiconductor processing or similar processes is disclosed. The evolving or diffusing gaseous substance is detected by spatially disposing from the irradiated or thermolyzed layer a detector layer that includes a compound having leaving groups that are sensitive to the gaseous substance being detected.

Abstract: The optical sensor contains an optical waveguide (1) with a substrate (104), waveguiding material (105), a cover medium (106) and a waveguide grating structure (101-103). By means of a light source (2), light can be emitted to the waveguide grating structure (101-103) from the substrate side and/or from the cover medium side (101-103). With means of detection (11), at least two differing light proportions (7-10) radiated from the waveguide (1) can be detected. For carrying out a measurement, the waveguide can be immovably fixed relative to the light source (2) and the means of detection (11). The waveguide grating structure (101-103) itself consists of one or several waveguide grating structure units (101-103), which if so required can be equipped with (bio-)chemo-sensitive layers. The sensor permits the generation of absolute measuring signals.

Abstract: The present invention pertains to biosensors based on uniquely designed polymer optical waveguides that are adaptable to a variety of environments, and to both chemical and biological species. In particular, the invention relates to polymer-based, index of refraction-mediated analyte sensing devices.

Abstract: Electronic absorption spectroscopy of a polyaniline film deposited on a polyethylene surface by chemical oxidation of aniline monomer at room temperature was used to quantitatively detect ammonia gas. The present optical ammonia gas detector was found to have a response time of less than 15 s, a regeneration time of less than 2 min. at room temperature, and a detection limit of 1 ppm (v/v) for ammonia, with a linear dynamic range from 180 ppm to 18,000 ppm.

Abstract: The present invention relates to the determination of the presence or concentration of an analyte in a sample by visual or electronic element, using polarization based sensing techniques (14) employing fluorescent sensing (11) and reference molecules (10).

Abstract: The present invention provides a real-time luminescent piezoelectric detector capable of sensing the presence of biological and chemical agents. This detector includes a free-standing thin film that is driven by a frequency drover to produce light emitted from an edge of the thin film. A surface layer sensitive to the biological or chemical agent to be detected is disposed on the surface of the thin film. In the presence of the biological or chemical agent to be detected, the light emitted from the edge of the thin film structure is altered. A processor capable of determining the presence and/or concentration of the biological or chemical agent in question based on the altered emitted light receives an output representative of the emitted light and outputs the status of the presence and/or concentration of the biological or chemical agent in question.

Abstract: A photometer including an elongated sample cell having a first end, a second end, and a passageway extending between the first end and the second end. Preferably, a ratio of a length of the sample cell to a lateral dimension of the passageway is at least 100 to 1. A first quartz window assembly is located at the first end of the sample cell and has a first port communicating with the passageway proximate to the first end, and a second quartz window assembly is located at the second end of the sample cell and has a second port communicating with the passageway proximate to the second end. An ultraviolet lamp is positioned to emit ultraviolet light through the first quartz window, the passageway, and the second quartz window, and an ultraviolet detector is positioned to receive the ultraviolet light emanating from the second quartz window. Preferably, the sample cell is operated at about ambient temperature, and the volume of the sample cell is no greater than about 0.

Abstract: In this invention, a mixture of a diazotizing reagent which reacts with nitrous ions to produce a diazo compound, a coupling reagent which couples with a diazo compound to produce an azo dye, and an acid is placed in pores of a transparent porous body to prepare a sensor element. Nitrogen dioxide gas is sensed in accordance with a color change before and after the sensor element is exposed to air to be measured for a predetermined time.

Abstract: An ultratrace detector system for hand-held gas chromatography having high sensitivity, for example, to emissions generated during production of weapons, biological compounds, drugs, etc. The detector system is insensitive to water, air, helium, argon, oxygen, and CO2. The detector system is basically composed of a hand-held capillary gas chromatography (GC), an insulated heated redox-chamber, a detection chamber, and a vapor trap. For example, the detector system may use gas phase redox reactions and spectral absorption of mercury vapor. The gas chromatograph initially separates compounds that percolate through a bed of heated mercuric oxide (HgO) in a silica—or other metal—aerogel material which acts as an insulator.

Abstract: A measuring system and method are provided for performing luminometric series analyses on reaction components to be investigated and the liquid samples containing the magnetizable carrier particles binding the components. Sample chambers receive the liquid samples. These sample chambers are transported to a measuring station on a conveyor. Permanent magnets act on the sample chambers with magnetic fields during transport. A separating station is also provided, which is preferably equipped with a suction and rinsing device to remove the surplus reaction components separated from the carrier particles that accumulate on wall areas of the sample chambers under the influence of the magnetic fields.

Abstract: This invention provides a fiber optic sensor and sensor devices for the reversible detection of basic gas analytes, including hydrazine, alkyl hydrazines, amines, ammonia, and related chemical species. The optical fiber sensor is formed in an optical fiber which conventionally comprises an optical fiber core and a cladding layer. Transducer molecules are immobilized in contact with an exposed surface of the fiber core to allow interaction of the immobilized species with analytes in the environment around the sensor. Preferred transducer molecules for detection of basic gases, particularly hydrazine and hydrazine derivatives, are xanthene dyes and triphenylmethane dyes, including malachite green and crystal violet. The sensors of this invention can be employed in a variety of device configurations including single-site sensors and multiple-site sensor networks.

Abstract: The invention concerns an apparatus comprising an intake scoop (2) for the gas sample to be analyzed and, coaxial to said scoop (2): two tubular sleeves (4) defining respectively an intake chamber (5) for an oxygen carrier gas opening into a first combustion chamber (8), and an intake chamber (11) for an oxidant gas opening into a second combustion chamber (9); a pair of electrodes (14) associated with a circuit (21) measuring the conductivity of a combustion zone located in the second combustion chamber (9) and focusing optics (19) focusing the image of the flame generated in the combustion chambers (8, 9) on the input orifice of a spectrophotometer (20); a processor (25) processes the data from the circuit (21) and from the spectrophotometer (20) to deduce therefrom the concentration in the searched elements. The invention is particularly useful for detecting sulphur, phosphorus and organic compounds.

Abstract: Gases flow to individual gas analysis cells. The cells are sequentially aligned with an infrared detector, which senses the composition and quantities of the gas components. Each elongated cell is tapered inward toward the center from cell windows at the ends. Volume is reduced from a conventional cell, while permitting maximum interaction of gas with the light beam. Reduced volume and angulation of the cell inlets provide rapid purgings of the cell, providing shorter cycles between detections. For coal and other high molecular weight samples, from 50% to 100% oxygen is introduced to the tubes. Cells are suspended from adjustable holders on a frame which is spaced from a table. The table is moved by a linear motor and a fixed platen. Sides of the table are shielded to prevent electromagnetic and magnetic motor interference with detected results. The entire table, cells, mounting plate and linear motor are mounted in a housing with aligned holes for the analysis energy source and detector.

Abstract: The invention is a fluorescent sensor element for detecting concentration changes of oxygen in an atmosphere suitable for high temperature applications such as automotive exhaust gases. It comprises an optical fiber, preferably silica, coated on at least a portion of its surface with a sol-gel processed porous uniform mixture of (1) matrix material of alumina, zirconia, titania, or silica or a mixture of any of them with (2) ceramic fluorescent indicator like Cu-ZSM-5 zeolite incorporated therein. In use of the sensor element in a system, a light source excites fluorescence in the indicator which is responsive to varying oxygen concentration in the contacted exhaust gas.

Abstract: An airborne hazardous material reader device capable of receiving a collection element. The reader device has a body forming a slot area for receiving the collection element. The body has a crushing mechanism located within the slot area for breaking ampules attached to the collection element containing chemical testing reagents, a micro-pump positioned proximate to the slot area for controlling the temperature next to the collection element, a diode reading component incorporated within the body for distinguishing color changes from the release of chemical testing reagents from the broken ampules, an indicator for indicating the presence of a hazardous material when the diode reading component distinguishes color changes and a microprocessor that coordinates the sequence of the reader device. A method for airborne hazardous material detection also is disclosed.

Abstract: This invention provides a reduced power consumption gas chromatograph system (10) which includes a capillary gas chromatograph column member (12) which contains a chemical sample to be analyzed. The gas chromatograph system further includes a heating mechanism (16) which extends throughout the length of the capillary gas chromatograph column member (12) and surrounds both the member (12) and a temperature sensing mechanism (14) which is mounted adjacent to the column member (12). The temperature sensing mechanism (14), the heating mechanism (16) and the column member (12) form a chromatograph column assembly (20) which includes a coiled section (28) where the components are tightly packed with respect to each other and allows for a reduced power consumption for temperature programming miniature gas chromatography column assemblies.

Abstract: Mass flow controllers are respectively placed in the middle of a hydrogen gas tube and air tube connected to a FPD. The flow controllers are controlled to supply hydrogen and oxygen from the nozzle to achieve the optimum mixture rate of hydrogen and oxygen for combustion of each target component in a sample. Since the mixture rate of hydrogen gas and air is optimum for each target component, the quantity of light emitted by the combustion increases and detection of each target component improves.

Abstract: A detection system for detecting contaminant gases includes a converter, a detector, a primary channel for delivering a target gas sample through the converter to the detector, and at least two scrubbing channels for delivering a reference gas sample through the converter to the detector. Each of the scrubbing channels includes a scrubber for removing basic nitrogen compounds from the reference gas sample, while the primary channel preferably transmits the target gas sample without scrubbing. The converter converts gaseous nitrogen compounds in the target gas sample to an indicator gas, such as nitric oxide (NO), and a control system directs the flow of a gas sample among the primary channel and the scrubbing channels. In accordance with one aspect of the invention, the basic-nitrogen-compound concentration can be measured by comparing the concentration of the indicator gas detected in the reference sample with the detected indicator-gas concentration in the target sample.

Abstract: A diagnostic assay device comprising a housing assembly and an image recording material housed therein that is exposed by a luminescent read-out signal generated by a luminescent activity triggered in response to displacement of a liquid carrier assembly carrying an analyte of interest with a reservoir containing an assay solution.

Abstract: A method and apparatus are disclosed for the near simultaneous detection of light emitted from ozone induced chemiluminescence of nitrogen and sulfur species capable of undergoing ozone induced chemiluminescence in a single instrument. A sample containing sulfur and/or nitrogen is first subjected to an oxidative/reductive process which generates ozone reactive nitrogen and sulfur species which are then forwarded to an specially designed ozone/detector chamber. The ozone relative species are brought in contact with ozone in the special chamber and the chemiluminescence of the nitrogen species and the sulfur species are measured and quantitated.

Abstract: An apparatus is used to determine whether a container moving along a conveyor is suitable for storing water. The apparatus includes a sampler that obtains a sample from the interior of the container as the container moves along the conveyor. A PID is connected to the sampler to receive the sample and produce a signal corresponding to contents of the sample. A controller is connected to the PID and receives and analyzes the signal to determine whether the container is suitable for storing water. The apparatus may include a vacuum source connected to the PID that produces a reduced pressure for drawing the sample through the PID. A flow restrictor may be positioned between the sampler and PID. The flow restrictor may provide variable resistance to set a desired clearance time through the PID and sensitivity of the PID.

Abstract: A method and apparatus is disclosed for sensing hydrocarbon in the vapor path of fuel dispensers using a fiber-optic sensor. The sensor includes an absorber-expander sensing structure mechanically coupled to the fiber body and responsive to the presence of effluent fuel components for absorbing the hydrocarbon therein and expanding in response thereto. The expansion activity has the effect of generating a microbend deformation in the fiber, producing detectable changes in the optical throughput representing the concentration of hydrocarbon that is sensed by the absorber-expander element. The fiber-optic sensor is particularly useful in a vapor recovery system by providing an optical signal that is representative of the ambient hydrocarbon concentration.

Abstract: A detector for detecting and measuring nitric oxide. Gas-permeable capillary membrane fibers transport a reagent solution through a plenum containing gases to be measured. Nitric oxide molecules penetrate the walls of the fibers and undergo a chemiluminescent reaction within. The fibers and the plenum are translucent, allowing photons emitted by the chemiluminescent reaction to escape and be detected by a photodetector. The reagent is buffered at an alkaline pH and mixed with the enzyme carbonic anhydrase to minimize the measurement errors caused by the presence of carbon dioxide in the gas to be measured.

Abstract: The concentration of a target gas is determined in an optical gas sensor system having an array of optical gas sensors wherein each sensor has a different sensitivity range for a target gas. An active sensor is selected from the array of optical gas sensors by determining which sensor has an optical transmittance value between 0% and 100%. Optical transmittance values of the active sensor are differentiated with respect to time. Concentration of the target gas is calculated as a function of both the rate of change of optical transmittance and the value of the optical transmittance at the beginning of the period over which the transmittance is differentiated. When a hazardous gas such as carbon monoxide is the target gas an alarm can be given when a threshold concentration is exceeded. Preferably, the transmittance values are converted to digital signals and processed in an eight-bit microprocessor to determine target gas concentration.

Abstract: A portable high-throughput liquid-absorption air sampler [PHTLAAS] has an asymmetric air inlet through which air is drawn upward by a small and light-weight centrifugal fan driven by a direct current motor that can be powered by a battery. The air inlet is so configured as to impart both rotational and downward components of motion to the sampled air near said inlet. The PHTLAAS comprises a glass tube of relatively small size through which air passes at a high rate in a swirling, highly turbulent motion, which facilitates rapid transfer of vapors and particulates to a liquid film covering the inner walls of the tube. The pressure drop through the glass tube is <10 cm of water, usually <5 cm of water. The sampler's collection efficiency is usually >20% for vapors or airborne particulates in the 2-3.mu. range and >50% for particles larger than 4.mu..

Abstract: A kit for monitoring mammalian reproductive cycles by monitoring variations in the quantity of one or more low molecular weight volatile compound having a molecular weight of less than 50 grams per mole present in a body constituent sample is disclosed. Samples of a body constituent selected from the group consisting essentially of humoral fluid, breath and body cavity air are collected from a female mammal a multiple number of times during the reproductive cycle. The quantity of a low molecular weight volatile compound in each sample is measured. In the preferred embodiment, the low molecular weight volatile compound, acetaldehyde, will be measured and monitored. Variations in the quantity of the low molecular weight volatile compound appearing in each sample is monitored to determine the phase of the mammal's reproductive cycle and to predict the occurrence of ovulation.

Abstract: An integrated biochemical sensor (200) for detecting the presence of one or more specific samples (240) having a device platform (355) with a light absorbing upper surface and input/output pins (375) is disclosed. An encapsulating housing (357) provides an optical transmissive enclosure which covers the platform (355) and has a layer of fluorescence chemistry on its outer surface (360). The fluorophore is chosen for its molecular properties in the presence of the sample analyte (240). The detector (370), light sources (365, 367, 407, 409) are all coupled to the platform (355) and encapsulated within the housing (357). A filter (375) element is used to block out unwanted light and increase the detector's (370) ability to resolve wanted emission light.

Abstract: The present invention and its claims encompass principles, methods, apparatus, and applications for detection, quantification, and monitoring of responses of gases, vapors, aerosols, and mixtures thereof to initiators of exothermic reactions. While the invention can be utilized for any concentration level, the intended, normal utilization is for gases in which the concentrations of species capable of participating in exothermic chemistry are too low to support self-sustaining exothermic reactions leading to detonations or deflagrations as well as for gases in which other factors prevent the exothermic reaction chemistry from becoming self-sustaining. This abstract shall not be construed to define or limit in any way the scope of the invention, which is measured by the appended claims.

Abstract: A laser array for determining the concentrations of gases. A simply acting device and a corresponding process are provided, which make possible a high signal resolution by reducing the interferences without prolonging the measurement time. The interferences occurring in the laser array are reduced by the laser source being set to perform longitudinal oscillations in the direction of the optical axis. These oscillations preferably have a sinus or sawtooth shape, and a frequency in the range of 10 to 1,000 Hz that does not otherwise occur in the laser array and an oscillation amplitude corresponding to one fourth to a multiple of the wavelength of the radiation of the laser source.

Abstract: The present invention provides dried chemical compositions comprising dried beads. Typically, the beads comprise reagents suitable for analysis of biological samples, in particular analysis of blood samples in centrifugal analyzers.

Abstract: An ultratrace detector system for hand-held gas chromatography having high sensitivity, for example, to emissions generated during production of weapons, biological compounds, drugs, etc. The detector system is insensitive to water, air, helium, argon, oxygen, and C0.sub.2. The detector system is basically composed of a hand-held capillary gas chromatography (GC), an insulated heated redox-chamber, a detection chamber, and a vapor trap. For example, the detector system may use gas phase redox reactions and spectral absorption of mercury vapor. The gas chromatograph initially separates compounds that percolate through a bed of heated mercuric oxide (HgO) in a silica--or other metal--aerogel material which acts as an insulator.

Abstract: An on-board gas composition sensor is disclosed for monitoring oxygen content levels in the exhaust gas (24) of an internal combustion engine (4). The gas composition sensor includes a sensor body (20) mounted inan exhaust stream from an engine (4), with a fiber-optic cable (18) running from the sensor body (20) to a silicon chip (13) containing a sensor assembly(10). The sensor assembly (10) includes a light source (12), mounted on the chip (13), for generating excitation light. Also, a fiber-optic coupler (16), formed in the chip, operatively engages a second fiber-optic cable (15), mounted in a groove on the chip. The second cable (15) connects to a fluorescence detector (34) and an excitation detector (36). The two detectors produce output signals (35, 37) that are used by the electronic engine control (8) to adjust engine operation.

Abstract: An integrated biochemical sensor (200) for detecting the presence of one or more specific samples (240) having a device platform (355) with a light absorbing upper surface and input/output pins (375) is disclosed. An encapsulating housing (357) provides an optical transmissive enclosure which covers the platform (355) and has a layer of fluorescence chemistry on its outer surface (360). The fluorophore is chosen for its molecular properties in the presence of the sample analyte (240). The detector (370), light sources (365, 367, 407, 409) are all coupled to the platform (355) and encapsulated within the housing (357). A filter (375) element is used to block out unwanted light and increase the detector's (370) ability to resolve wanted emission light.

Abstract: A solid object carrying a catalyzer thereon is placed in a closed reaction chamber into which test gases are supplied and is heated up to a temperature of 1000.degree. C. Adsorbates are formed on the surface of the solid object under the test gas flow in the closed reaction chamber. Infrared radiations radiated from the adsorbates are emitted through an infrared-transmissive window hermetically formed on a wall of the closed reaction chamber, and are analyzed by an infrared radiation spectrometer and observed by a microscope. The infrared-transmissive window is cooled down by a cooling device attached thereto so that the temperature of the window does not exceed a certain level, e.g., 200.degree. C. Thus, the adsorbates formed on the solid object can be detected and analyzed under conditions where the test gas is actually flowing and the temperature of the solid object is elevated up to a high level.

Abstract: Disclosed are oxygen concentration and/or pressure sensing devices and methods which incorporate photoluminescent silica aerogels. Disclosed sensors include a light proof housing for holding the photoluminescent aerogel, a source of excitation radiation (e.g., a UV source), a detector for detecting radiation emitted by the aerogel, a system for delivering a sample gas to the aerogel, and a thermocouple. Also disclosed are water resistant oxygen sensors having a photoluminescent aerogel coated with a hydrophobic material.

Abstract: A method for detecting dimethylaluminumhydride (DMAH) comprises sensing the aluminum oxide particles produced by the reaction of the DMAH with air (or with a small amount of oxygen). This is accomplished using a particle-sensing device, such as those commonly used to detect smoke, particularly an ionization-type detector.

Abstract: A gas detection and measurement system includes a light source, a light sensor, a test cell body having a first fluid port and a second fluid port, and first and second optical paths from the light source to the light sensor through the test cell. The first and second optical paths have different lengths. As fluid flows through the test cell body, light intensity measurements are taken along the first and second optical paths so that the concentration of a target gas within the fluid can be calculated.