Abstract: A medical gas alarm system for use in a healthcare facility having a medical gas system and having a network of computer devices is provided. The alarm system includes at least one area alarm controller adapted to receive a first signal indicative of a condition of a first portion of the medical gas system. The area alarm controller is adapted to communicate with the network. The alarm system also includes at least one master alarm controller adapted to receive a second signal indicative of a condition of a second portion of the medical gas system. The master alarm controller is adapted to communicate with the network. The area alarm controller is adapted to communicate with the master alarm controller through the network.

Abstract: The present invention relates to a gas-monitoring assembly and method for selectively determining the presence of a target gas in a gaseous environment that potentially comprises one or more interfering gases. Such gas-monitoring assembly and method specifically employ one or more gas sensors one or more getters arranged and constructed to reduce cross-interference caused by potential presence of the interfering gases in such gaseous environment to be monitored. The gas-monitoring assembly and method of the present invention are capable of monitoring a gaseous environment with respect to potential presence of multiple target gases that may interfere with one another.

Abstract: The present invention provides an odor measuring apparatus capable of assuredly detecting and evaluating such odors that cannot be detected by a measurement apparatus using conventional odor sensors. In an embodiment of the present invention, a gas sample to be measured is introduced into the column 10 of a gas chromatograph 1 to temporally separate it into odor components, which are then introduced into a mass spectrometer (MS) 2 and an odor discriminator 3 in parallel. The data processor 51 creates a chromatogram and/or a mass spectrum from the detection signals generated by the detector 24 of the MS 2, and also calculates the similarity of each odor component to standard odors and/or the degree of contribution from the detection signals generated by the detection circuit 33 of the odor discriminator 3. The processor 51 displays a similarity radar chart or similar graphic information on the display 53, where each peak present on the chromatogram is associated with the information.

Abstract: In a hydrogen concentration detecting method of detecting whether the hydrogen concentration is equal to or higher than a reference concentration; using a hydrogen detecting apparatus 1 comprising a detecting element 4 made of a hydrogen absorbing alloy, a microheater 2, a substrate 3, and a strain gauge 6, where the operation of the microheater 2 is halted during a normal state; however, once the strain gauge 6 detects a volume change of the detecting element 4, the microheater 2 starts heating the detecting element 4.

Abstract: A gas detector that includes at least one source of infrared radiation, at least two analytical detectors, each analytical detector adapted to provide an output signal indicative of a first gas of interest and positioned to receive radiation from the source of radiation, at least one reference detector adapted to receive radiation of a predetermined wavelength, a sample chamber for receiving a gaseous sample, and an optical path length disposed between the source of radiation and the analytical detectors and passing through the sample chamber.

Abstract: A system for determining polarization of a gas comprises a container that contains the polarized gas. An oscillator circuit comprises an NMR coil that is positioned adjacent to the container. A pulse generator circuit is configured to generate an electrical pulse that may be transmitted to the optical cell through the NMR coil to excite the polarized gas responsive to a control processor. A Q-reduction circuit that is independent of the pulse generator circuit is configured to reduce oscillations in the oscillator circuit from the transmitted electrical pulse responsive to the control processor. A receive circuit is responsive to an electrical signal that is induced in the oscillator circuit due to the electromagnetic excitation of the polarized gas. The control processor is configured to determine the polarization of the gas based on the output signal of the receive circuit.

Abstract: A sensor system for detecting the presence of at least one specific component in a fluid medium such as an exhaust gas. A sensor is mounted in a sensor body for detecting the presence of at least one specific component and providing a representative signal that is transmitted to a remote receiver for processing. A power source such as a thermopile provides power for the sensor and the transmitter. Preferred are sensors that detect a plurality of different components in the gas and provide a distinct signal for each component. A preferred transmitter is designed to transmit at a low duty cycle so as to conserve power. A preferred sensor is electronic, has the capability for self-diagnostics and self-calibration, and causes a change in current when exposed to the component, such as a functionalized field effect transistor.

Abstract: Sidestream gas sampling assembly that does not substantially degrade the waveform of expired gases. The gas sampling assembly includes a sample cell portion integrated with a filter portion for separating undesired liquid condensate from respiratory gases to be monitored. The gas sampling assembly is configured to receive expired gases through a gas sampling line, filter undesired liquid condensate from the expired gases through hydrophobic fiber elements and communicate the filtered gases to a sample chamber which is in close proximity to the filter where measurements may be taken thereof e.g., optical or infrared sensing mechanisms. The gases that are substantially free of liquid condensate are then exhausted from the sample chamber.

Abstract: Sensor arrays and sensor array systems for detecting analytes in fluids. Sensors configured to generate a response upon introduction of a fluid containing one or more analytes can be located on one or more surfaces relative to one or more fluid channels in an array. Fluid channels can take the form of pores or holes in a substrate material. Fluid channels can be formed between one or more substrate plates. Sensor can be fabricated with substantially optimized sensor volumes to generate a response having a substantially maximized signal to noise ratio upon introduction of a fluid containing one or more target analytes. Methods of fabricating and using such sensor arrays and systems are also disclosed.

Abstract: A chemiresistor sensor probe for detecting target analytes. The probe includes a body having a first control surface and a second control surface recessed within the first. A sensor film comprises numerous conductive particles disposed upon the second surface. The film swells upon absorbing one or more analytes for which it has an affinity, thus causing the conductive particles to become more dispersed and increasing the resistance between the particles. The thickness of the film is equal to the distance between the first surface and the second surface, thus permitting the thickness to be controlled by varying the distance between the control surfaces. The robustness of the sensor probe is enhanced by placing a porous or mesh electrode along with, or in place of, a chemical binding agent between the film and the terminals. The robustness is also improved by placing a diode in series with the sensor circuit.

Abstract: System and method of aerosolized agent detection. Multi-part collection tape is employed for capturing particles of interest for immediate analysis and optional forensic preservation and recording information related to capture and subsequent real-time analysis. Laser induced breakdown spectroscopic processing is employed and spectra attributable to known collection tape materials is subtracted to derive particle spectra for comparison to known hazardous agent spectra.

Abstract: The present invention provides for variable-range hydrogen sensors and methods for making same. Such variable-range hydrogen sensors comprise a series of fabricated Pd—Ag (palladium-silver) nanowires—each wire of the series having a different Ag to Pd ratio—with nanobreakjunctions in them and wherein the nanowires have predefined dimensions and orientation. When the nanowires are exposed to H2, their lattace swells when the H2 concentration reaches a threshold value (unique to that particular ratio of Pd to Ag). This causes the nanobreakjunctions to close leading to a 6–8 orders of magnitude decrease in the resistance along the length of the wire and providing a sensing mechanism for a range of hydrogen concentrations.

Abstract: When the ignition switch of a vehicle is turned OFF, a purging process for increasing the flow of an off-gas fluidizing in each of the outlet side pipings of a fuel cell and discharging water remaining in a fuel cell system to an outside is started to be executed, and the amount of current conductance to the heater of the gas sensor is increased synchronously with the start of the execution of the purging process. With the completion of the purging process, the fluidization of the off-gas in each of the outlet side pipings stops, and the amount of current conductance to each of the units of the gas sensor (for example, an electrifying voltage) is gradually decreased depending on a predetermined current conductance reducing amount which is preset, thereby stopping the current conductance to each of the units and the amount of current conductance to the heater is gradually decreased, thereby stopping the current conductance to the heater.

Abstract: The present invention provides an odor discriminating apparatus capable of determining the similarities or differences between plural odors with respect to the odor quality and the odor intensity, and showing the measurement result in such a manner that helps the user to correctly understand the result. According to the present invention, plural samples of a reference odor gas, each sample having a different concentration, are measured with m pieces of odor sensors. Based on the measurement result, a calibration curve is created in an m-dimensional space formed by the detection signals of the m pieces of odor sensors (Steps S1–S3). Next, a measurement point U0 representing the measurement result of a subject odor is plotted in the m-dimensional space.

Abstract: The invention concerns a method and apparatus for indicating a parameter of a transmitted fluid. One embodiment of the invention comprises a fluid source operatively coupled to a conduit for transmitting a fluid from the fluid source. In addition, a sensor detects a parameter of the fluid, such as the percent oxygen content of the fluid. In response to the sensor detecting the parameter of the fluid, an indicator illuminates a portion of the conduit if a predetermined condition, such as a minimum percent oxygen content of the fluid, is satisfied.

Abstract: The invention provides a portable gas detector of a novel structure that is easy to be fabricated as a small-sized one handy to carry and high in convenience for use. The portable gas detector has a housing in the form of a slim and flat box holdable by grasping with a hand, and a foreside half portion in the interior of he housing is provided as a functional part region, and a rear half portion in the interior of the housing is provided as a battery part region. In the functional part region, one of 5 gas sensors is arranged at a curved portion in a gas sensor-arranging region of an L shape as a whole, and 2 gas sensors are arranged in a row in both lateral and vertical directions of the above gas sensor, respectively. A gas sucking means is arranged in a region, the 2 directions of which is sectioned by the gas sensor-arranging region.

Abstract: A modular gas measuring system with a basic unit (1) with electric supply and data lines connected to it, a measuring unit (2), which is equipped with a gas sensor and with a microprocessor and is connected to the basic unit (1) by means of snap closures to form a functional unit. At least one expansion module, is accommodated by the functional unit. The modular design, of optionally accommodating different expansion modules, so that the properties and the possible applications of the gas measuring system can be expanded in a simple manner.

Abstract: A vapor sensing device that is sufficiently small and lightweight to be handheld, and also modular so as to allow the device to be conveniently adapted for use in sensing the presence and concentration of a wide variety of specified vapors. The device provides these benefits using a sensor module that incorporates a sample chamber and a plurality of sensors located on a chip releasably carried within or adjacent to the sample chamber. Optionally, the sensor module can be configured to be releasably plugged into a receptacle formed in the device. Vapors are directed to pass through the sample chamber, whereupon the sensors provide a distinct combination of electrical signals in response to each. The sensors of the sensor module can take the form of chemically sensitive resistors having resistances that vary according to the identity and concentration of an adjacent vapor.

Abstract: A gas sensor (10) including a measurement chamber (28) into which a gas GS is flown and a detection element main body (40) facing the measurement chamber (28). The detection element main body (40) includes an element case 42, and a protective film (48) is adhered to a bottom surface thereof. An acoustic matching plate (50) and a piezoelectric element (51) of a substantially columnar shape and a tube body (52) provided in a position surrounding the acoustic matching plate 50 and the piezoelectric element 51 are housed in the element case (42). A filler is then introduced into the element case (42), whereby the acoustic matching plate (50), the piezoelectric element (51), and the tube body (52) are sealed by a filled layer (99).

Abstract: A gas detector and process for detecting a fluorine-containing species in a gas containing same, e.g., an effluent of a semiconductor processing tool undergoing etch cleaning with HF, NF3, etc. The detector in a preferred structural arrangement employs a microelectromechanical system (MEMS)-based device structure and/or a free-standing metal element that functions as a sensing component and optionally as a heat source when elevated temperature sensing is required. The free-standing metal element can be fabricated directly onto a standard chip carrier/device package so that the package becomes a platform of the detector.

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: A photoacoustic ozone detector includes an acoustic chamber, an ultraviolet light source, and a detector to detect audio signals. The acoustic chamber has an inlet for receiving a gas mixture containing ozone and an outlet for removing the gas mixture from the chamber. The ultraviolet light source generates ultraviolet light having wavelengths shorter than 400 nm, and the ultraviolet light is modulated at a modulation frequency substantially equal to a resonant frequency of the acoustic chamber. The ultraviolet light source is positioned relative to the acoustic chamber so that the ultraviolet light passes through the gas mixture in the acoustic chamber. The detector detects an audio signal in the acoustic chamber having a frequency substantially equal to the modulation frequency of the ultraviolet light. A signal processor generates an output indicative of a concentration of the ozone in the gas mixture based on the detected audio signal.

Abstract: The invention concerns a gas analyzer comprising: a measuring volume (2), a radiation source (1) for providing a beam to pass said measuring volume; a heat sink (16) for said radiation source; at least one thermal detector (3) having a hot junction within a support structure and receiving the radiation and a cold junction for reference within the same support structure and protected from said radiation; at least one optical bandpass filter (9) between said hot junction and said radiation source; and a thermal mass (11), which is formed of a material having high thermal conductance. The thermal mass has a cavity with a bottom step (34) and a rim (32), and a first length therebetween. The support structure has a frontal edge (35) and a base plate lip (33), and a second length therebetween. There is a radial gap between the thermal mass and the support structure.

Abstract: A sensor element can comprise a co-fired heater section, a sensing section, and a third insulating layer disposed between the electrode portion and the temperature sensor. The heater section can comprise a heater, a shield, and a temperature sensor, with a first insulating layer disposed between the heater and the shield, and a second insulating layer disposed between the shield and the temperature sensor. The sensing section can comprise an electrode portion and a sensing portion, wherein the sensing portion is disposed on a side of the electrode portion opposite the heater section.

Abstract: A system and method for inferring an electronic rendering (170) of an environment (110) comprises a plurality of devices (341 and 345), and a processing device. Each wireless device is capable of determining a distance between a neighboring wireless device. Moreover, each device is capable of performing at least one of the following: determining an environmental attribute of the environment, and determining a location of an object in the environment. The processing device gathers information determined from the plurality of devices and infers the electronic rendering of the environment based on the information gathered.

Abstract: A multiple port valve integrated with the function of the sample shut off valve is disclosed. The integration of the sample shut off function eliminates extra plumbing and labor costs associated with a separate sample shut off valve. Additionally, the multiple port valve integrated with the function of the sample shut off valve provides a shorter equilibration time and less tubing volume.

Abstract: A mechanical breathing aid has first and second inlets respectively connectable to a source of air and a source of oxygen. A mixing location is in gaseous communication with the first and second inlets, at which controlled amounts of air and oxygen from the respective inlets are mixed. An acoustic analyzer operates during a measurement procedure to access a moisture content value for air from the source of air, to generate acoustic velocity-related information from acoustic energy interaction with the breathing gas, and to determine therefrom an oxygen content. The analyzer operates during a calibration procedure to generate acoustic velocity-related information from acoustic energy interaction with air from the source of air, and to determine therefrom an oxygen content value for the air from which is determined a moisture content value for air.

Abstract: The present invention generally relates to nucleic acid-based sensors and methods for detecting volatile analytes. More particularly, this invention relates to nucleic acid-based optical sensors, sensor arrays, sensing systems and sensing methods for intelligent sensing and detection of unknown materials by way of real-time feedback and control of sampling conditions.

Abstract: A liquid electrode mixture for use in a gas sensor having from about 60 to about 240 milligrams of platinum black catalyst; from about 900 to about 1100 milligrams of water; from about 300 to about 400 microliters of 1-propanol; and from about 100 microliters to about 150 microliters of a polymer mixture comprising from about 40% to about 80% PTFE by weight and water.

Abstract: A hydrocarbon sensor and collector. An element that is capable of absorbing and releasing hydrocarbons is positioned in the air intake system of a vehicle, upstream from the engine and wholly in the airflow. The element has a plurality of chambers defined in it that allow air to pass through the element. The hydrocarbon sensor and collector also includes a means for detecting the level of hydrocarbons absorbed by the element.

Abstract: An infrared absorption measurement method includes: (a) measuring infrared absorption of a measurement target component in a state in which a sample gas including the measurement target component is decompressed; (b) calculating an absorption area in a peak region of the measurement target component in the infrared absorption shown in a graph which shows the relationship between the wave number and absorbance of the sample gas; and (c) calculating a concentration of the measurement target component in the sample gas based on the absorption area and pressure of the sample gas during decompression.

Abstract: The invention relates to a chamber (2) for gas sensors (9) to be used in a device (1) for detecting aromas or odors. The chamber (2) comprises three portions (5, 6, 7) in which there is a uniform, turbulence-free flow (F) of gas or vapors to be analyzed, and at least one gas sensor (9) positioned in the central portion in such a way as to be immersed in and to laterally and tangentially interact with the flow (F). The chamber (2) also comprises a heating and temperature regulating device (16, 17). The invention also relates to an odor detection method which comprises a step in which a uniform, turbulence-free flow (F) of gas or vapor interacts with a gas sensor (9) laterally and tangentially.

Abstract: A method and system removes nuclear, biological and chemical (NBC) agents from an air stream from a facility HVAC. The system includes an irradiation zone, a saturation zone and a precipitation zone. A contaminant detection apparatus controls the irradiation, saturation and precipitation of the air stream. The irradiation destroys biological agents along with saturation of air stream with a water based solution. The biological debris and dissolved chemical agents are precipitated out of the air stream by condenser coils. Nuclear agents are removed from the air stream by a diverting the air stream though a bypass filter containing high mass particulate filters and activated charcoal. The contaminants are stored for later removal and destruction. The contaminate detection apparatus includes NBC sensors.

Abstract: A poison resistant combustible gas sensing element, a method for its production and a method for determining poisoning of the element. The element includes an electric heating element, an inner layer coated on the electric heating element and containing a precious metal catalyst supported on a porous oxide, the precious metal catalyst catalyzing combustion of a combustible gas to be detected by the element, and an outer layer overlaying the first layer, and containing a catalytic compound capable of trapping gases which poison the precious metal catalyst, the catalytic compound being supported on a porous oxide.

Abstract: A chemical sensing system has: an interrogation unit operable to wirelessly transmit an interrogation signal and wirelessly receive a response; an environmentally sealed container for holding a chemical analyte; a sensor array unit in fluid communication with the analyte disposed within the container, where the sensor array unit is operable to generate a response in the presence of a chemical stimulus; and a passive responder unit connected with the sensor array unit, the responder unit being powered from the interrogation signal, where the responder unit is operable to wirelessly receive the interrogation signal and wirelessly transmit the response to the interrogation signal to the interrogation unit.

Abstract: An oxygen sensor heater control determines heater activation based on an open-loop control parameter and a correction factor that compensates for part-to-part variability. Following a cold start where the heater temperature can be reliably estimated, the engine controller predicts the resistance of the heating element and heater circuit at the desired operating temperature of the sensor, and computes the correction factor for heater activation based on the predicted resistance values and nominal resistance values. At least one predicted value is stored in non-volatile memory, and used to compute the correction factor following a warm or hot start of the engine.

Abstract: A gas sensor comprising: a gas sensor element extending in an axial direction; a cylindrical metal shell enclosing said gas sensor element such that a leading end portion of said gas sensor element protrudes from its own leading end; and a protector fixed on said metal shell and covering said leading end portion of said gas sensor element, wherein said protector includes: a cylindrical outer cover portion fixed on said metal shell and having gas introducing apertures; and a cylindrical inner cover portion arranged on an inner side of said outer cover portion and having elastic portions being capable of being elastically deformed by a pushing force acting in an axial direction, and said inner cover portion is so clamped between said metal shell and said outer cover portion that said elastic portions are elastically deformed by said axial pushing force.

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 vacuum heat treatment furnace comprising a furnace shell, a casing arranged in an inner side of the furnace shell, a heat insulating layer consisting of a thick plate-like alumina-silica series ceramic fiber blanket and a thin plate-like alumina series ceramic material arranged in an inside of the casing, and a heater arranged in a heating room surrounded by the heat insulating layer.

Abstract: A system and methods of the present invention advantageously provide efficient mail processing and handling that, as compared to existing procedures, enhances detection within the mail being processed or handled of biological, germ, chemical, or other harmful agents. A system and methods provide additionally a higher level of quality and consistency for processing and handling mail so that concerns over contamination of postal workers and potential mail recipients are reduced. A system and methods further provide enhanced disabling of contaminated mail contents, mail, mail equipment, mail containers, and mail personnel due to exposure or contact with harmful agents associated with mail.

Abstract: An apparatus for detecting and indicating the presence of combustion products comprising a first combustion product monitor for monitoring for the presence of a first combustion product and quantifying said first product; a second combustion product monitor for monitoring for the presence of a second combustion product and quantifying said second product; and, an alarm connected to the first and second combustion product monitors for triggering an alarm when an alarm condition is satisfied, said alarm condition being at least one of the group consisting of the quantified presence of the first combustion product exceeding a first-product threshold level and the quantified presence of the second combustion product exceeding a first second-product threshold level; and, the quantified presence of the second combustion product exceeding a second second-product threshold level.

Abstract: A more efficient method for combustion or oxidation of samples containing nitrogen, phosphorus and/or sulfur to their corresponding oxides is disclosed, where method uses multi-staged addition of an oxidizing agent to enhance oxidation and liberation of nitrogen, phosphorus and/or sulfur oxides for subsequent detection. The method of the present invention allows for the injection of larger samples or the introduction of a greater amount of sample per unit of time which results in a larger amount of analyte being delivered to the detector per unit of time, thereby improving detection limits and detection efficiency.

Abstract: The gas monitoring system may include a gas line, an oxygen sensor, a filter, a pump, a indicator, and a controller. The gas line is configured to convey gas from a space configured to receive inert gas to a location remote from the space. The oxygen sensor is fluidly coupled to the gas line at the location. The oxygen sensor is configured to determine a partial pressure of oxygen present in the gas. The filter is fluidly coupled to the gas line between the space and the location. The filter is configured to remove combustible contaminants from the gas before it reaches the oxygen sensor. The controller is electrically coupled to the oxygen sensor and to the indicator. The controller is configured to activate the indicator when the partial pressure of oxygen exceeds a predetermined level.

Abstract: An apparatus for treating compressed air from a rail yard compressed air supply pipeline leading from a central air compressor to outlets at remote locations in a rail yard prior to charging air brake lines of trains with compressed air from the pipeline to prevent contaminants such as moisture, entrained atomized oil and/or particulates such as rust from getting into the air brake line of the train. The apparatus includes an air line, an air inlet connector at one end of the air line, an outlet connector at the other end of the air line, and at least one separator device interposed in the air line between the inlet connector and the outlet connector for separating contaminants from a stream of compressed air passing through the apparatus.

Abstract: A poison resistant combustible gas sensing element, a method for its production and a method for determining poisoning of the element. The element includes an electric heating element, an inner layer coated on the electric heating element and containing a precious metal catalyst supported on a porous oxide, the precious metal catalyst catalyzing combustion of a combustible gas to be detected by the element, and an outer layer overlaying the first layer, and containing a catalytic compound capable of trapping gases which poison the precious metal catalyst, the catalytic compound being supported on a porous oxide.

Abstract: An inverse analysis method for characterizing diffusion of vapor from an underground source of volatile contaminant using data taken by an in-situ sensor. The method uses one-dimensional solutions to the diffusion equation in Cartesian, cylindrical, or spherical coordinates for isotropic and homogenous media. If the effective vapor diffusion coefficient is known, then the distance from the source to the in-situ sensor can be estimated by comparing the shape of the predicted time-dependent vapor concentration response curve to the measured response curve. Alternatively, if the source distance is known, then the effective vapor diffusion coefficient can be estimated using the same inverse analysis method. A triangulation technique can be used with multiple sensors to locate the source in two or three dimensions. The in-situ sensor can contain one or more chemiresistor elements housed in a waterproof enclosure with a gas permeable membrane.

Abstract: A method and apparatus for determining the effective composition of a mixture of gases including a plurality of hydrocarbon gases, the method comprising selecting one or more effective hydrocarbons to represent the plurality of hydrocarbon gases in the gas mixture, the number of effective hydrocarbons being less than the number of hydrocarbon gases in the gas mixture whose composition is to be determined; measuring a number of characteristics of the gas mixture whose effective composition is to be determined, the number of characteristics to be measured being one less than the total number of components to be determined and determining the effective composition of the mixture of gases from the measurements of the characteristics of the gas mixture, a predetermined parameter dependent upon the characteristic measured and knowing that the sum of the components of the gas mixture equals 100%.

Abstract: Disclosed are resonant gas sensors and methods for forming and using the disclosed sensors. The sensors include a resonator including a layer comprising adsorptive nanostructures, for example carbon nanotubes, activated carbon fibers, or adsorptive nanowires. The dielectric of the resonator is in electrical communication with the layer comprising adsorptive nanostructures such that the effective resonant frequency of the resonator depends on both the dielectric constant of the dielectric as well as the dielectric constant of the adsorptive layer. In some embodiments, the nanostructures can be degassed. The sensors can detect the presence of polar gases, non-polar gases, organic vapors, and mixtures of materials with both high sensitivity and high selectivity.

Abstract: A gas sensor includes a silicon substrate provided with a recess, an insulating layer, a first and a second conductive patterned layers and a detecting portion for sensing a gas which passes there through. In the gas sensor, the insulating layer is formed on a top portion of the silicon substrate which does not form the recess. The first and the second conductive patterned layers extend over the recess, thereby being apart from the silicon substrate physically. The detecting portion is formed on both portions of the first and the second conductive patterned layers.

Abstract: A medical gas alarm system for use in a healthcare facility having a medical gas system and having a network of computer devices is provided. The alarm system includes at least one area alarm controller adapted to receive a first signal indicative of a condition of a first portion of the medical gas system. The area alarm controller is adapted to communicate with the network. The alarm system also includes at least one master alarm controller adapted to receive a second signal indicative of a condition of a second portion of the medical gas system. The master alarm controller is adapted to communicate with the network. The area alarm controller is adapted to communicate with the master alarm controller through the network.