Abstract: An electrochemical suspended element-based sensor system includes a solution cell for holding an electrolyte comprising solution including at least one electrochemically reducible or oxidizable species. A working electrode (WE), reference electrode (RE) and a counter electrode (CE) are disposed in the solution. The CE includes an asymmetric suspended element, wherein one side of the suspended element includes a metal or a highly doped semiconductor surface. The suspended element bends when current associated with reduction or oxidation of the electrochemically reducible or oxidizable species at the WE passes through the suspended element. At least one measurement system measures the bending of the suspended element or a parameter which is a function of the bending.

Abstract: An apparatus and methods for monitoring the status of a cell that consumes oxygen. In one embodiment of the present invention, the method includes the steps of confining the cell in a sensing volume, measuring dynamically intracellular or extracellular signaling of the cell, and determining the status of the cell from the measured intracellular or extracellular signaling of the cell.

Abstract: A hydrogen sensor includes a thin film layer formed on a top surface of a planar optical transmission medium, and a catalyst layer formed on a top surface of the thin film layer. A first interface is created between the planar optical transmission medium and the thin film layer. A substrate is joined to a bottom surface of the planar optical transmission medium so that a second interface is created between the planar optical transmission medium and the substrate. On entering a first end portion of the planer optical transmission medium, light from a light source is spread by an entrance section, and the spread light is transmitted inside the planar optical transmission medium to a second end portion by being reflected by the first and second interfaces alternately. Light exiting from the second end portion is transmitted to an optical sensor by an exit light-collecting section.

Abstract: A film for detecting fluoride concentrations is disclosed. The film includes an organic matrix having a lipophilic aluminum compound incorporated therein. The lipophilic aluminum compound is adapted to selectively bind with fluoride ions via a binding interaction. The fluoride is detectable through optical or electrochemical detection of the binding interaction.

Abstract: A diagnostic test device comprises means for sampling a liquid biological sample. Means is provided for reacting the sample with a reagent to provide one or more visible indicia. A photodetector for scans a detection region to produce a pulsed output indicative of the presence of the one or more indicia. The photodetector is connected to a signal processing circuit for processing the pulsed output. The signal processing circuit produces an output change in response to light intensity variation which is substantially independent of baseline current.

Abstract: A sensing arrangement detects a compound of interest within a gas sample. An amplifying fluorescent polymer produces an output signal that varies in response to an interaction of the amplifying fluorescent polymer with the compound of interest. Additionally, an infrared illumination source produces infrared electromagnetic energy that causes the amplifying fluorescent polymer to generate the output signal. A MEMS detector is positioned to receive the output signal generated by the amplifying fluorescent polymer, and produces an output electrical signal that is responsive to an interaction between the compound of interest and the amplifying fluorescent polymer. The output electrical signal is responsive to a quenching of the output signal of the amplifying fluorescent polymer. A pattern database stoics pattern data corresponding to characteristics of compounds of interest.

Abstract: The present invention relates to a method and system of array imaging that extends or maximizes the longevity of the sensor array by minimizing the effects of photobleaching. The imaging system has a light source, a variable exposure aperture, and a variable filter system. The system extends the longevity of sensors by (1) using the variable exposure aperture to selectively expose sections of the sensor array containing representative numbers of each type of sensor, and/or (2) using the variable filter system to control the intensity of the excitation light, providing only the intensity required to induce the appropriate excitation and increasing that intensity over time as necessary to counteract the effects of photobleaching.

Abstract: Airborne particles are impacted on a collection surface, analyzed, and then the collection surface is regenerated. Thus, the same collection surface can be used in numerous cycles. The analysis can be focused on one or more properties of interest, such as the concentration of airborne biologicals. Sensors based on regenerative collection surfaces may be incorporated in many networks for applications such as building automation.

Abstract: The present invention relates to a class of fluorescent, organic nanofibrils, and particularly the films comprising entangled piling of these nanofibrils exhibiting effective quenching of their fluorescence upon exposure the vapor of explosives. The invention also relates to a sensor and a method for sensing the explosives vapor and other volatile organic compounds, including the explosives taggants through the modulation of the fluorescence of the nanofibril film and the electrical conductivity of the nanofibrils. The invention also relates to a development of synthetic methods, protocols and techniques that leads to production of various arylene-ethynylene macrocycle (AEM) molecules, which consist of a shape-persistent, toroidal scaffold in planar conformation, with minimal ring strain and highly tunable ring sizes (from 0.5 nm to above 10 nm).

Abstract: Photo-oxidation catalysts and methods for cleaning a metal-based catalyst are disclosed. An exemplary catalyst system implementing a photo-oxidation catalyst may comprise a metal-based catalyst, and a photo-oxidation catalyst for cleaning the metal-based catalyst in the presence of light. The exposure to light enables the photo-oxidation catalyst to substantially oxidize absorbed contaminants and reduce accumulation of the contaminants on the metal-based catalyst. Applications are also disclosed.

Abstract: An alcohol sensor having gas-sensitive layers made of polymers or inorganic oxides wherein a signal is read out by means of work function change which is produced in the form of a field-effect transistor.

Abstract: Methods are disclosed for producing a bioweapon-sensitive fibrous-network product, wherein the subject products exhibit a color change in response to exposure to a biological agent (or portion thereof) as used in a biological weapon. Also disclosed are fibrous-network products that contain units of biopolymeric material that impart a color change to the products in response to exposure to a biological agent (or portion thereof) as used in a biological weapon.

Abstract: Methods for forming hydrogen sensing materials include forming a palladium alloy thin film having less than about 83 atomic percent of palladium, and annealing the palladium alloy thin film to relieve residual stress and increase atomic intermixing of the nanorystaline lattice, while maintaining a grain size close to the grain size of the nonannealed palladium alloy thin film. For example, the sensing material may include a palladium-gold alloy thin film having about 60 atomic percent of palladium and about 40 atomic percent of gold. The palladium-gold alloy thin film is then annealed at a temperature of about 200 degrees Celsius for 1 hour. Methods for detecting hydrogen containing gas in which the hydrogen sensing material is maintained in a single phase when exposed to the hydrogen containing gas, and optical hydrogen sensors are also disclosed.

Abstract: Methods and insulator electrode devices for performing electrochemical reactions are disclosed. The devices consist of high specific surface area electrodes based on a channeled conducting base material that has been coated with an organic or inorganic insulating film or multiple layers of such films. The chemical reactions are exemplified by exciting one or several label compounds into an excited state which is spontaneously de-excited by emission of ultraviolet, visible or infrared light, in aqueous solution. This provides the basis for reproducible analytical applications in bioaffinity assays such as immunoassays and DNA-probing assays.

Abstract: A method of estimating strength of forming photochemical ozone utilizing a pump and probe technique is disclosed along with an apparatus for estimating strength of forming photochemical ozone utilizing a pump and probe means whereby strength of forming photochemical ozone can be estimated without measuring a concentration of each type of various reactive hydrocarbons in order to predict strength of forming photochemical ozone from rates of their reaction with OH radicals. Atmosphere (11) is irradiated with a pumping laser light (2c) to photolyze ozone therein, thereby forming excited oxygen atoms O(1D) which are then caused to react with water vapor to form OH radicals. The OH radicals are irradiated with a probing laser light (3e) to excite electrons therein. A fluorescent light emitted when the excited electrons are relaxed to transition is measured in a time sequence.

Abstract: A Fabry-Perot cavity has a pair of partially transmissive, partially reflective, surfaces. A first of the surfaces is flexibly suspended adjacent and parallel to a second of the surfaces. A gap exists between the surfaces. A variable electrostatic potential permits this gap to be adjusted. A translucent chemical layer is disposed on the first surface. A photosensor is attached to the second surface. Light irradiates the photosensor through the chemical layer and the first and second surfaces wherein the light is also partially reflected between the surfaces. A sensing environment is provided wherein an agent undergoes a reaction with the chemical layer as well as an environment wherein the reaction does not occur. The output of the photosensor is measured to assess a change in spectrum and spectral intensity for each of the sensing environments. The gap between the surfaces as well as the light used are selected to provide an optimum photosensor output.

Abstract: A breath alcohol detection device includes a one-piece multi-passage block with attached sensors, a valve and a fuel cell. The cell accurately determines the BrAC of a prospective vehicle operator. In the event the BrAC is less than the legal maximum for a territory, the device unlocks an ignition interlock to permit starting of the engine and operation of the vehicle.

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

Abstract: A device for measuring and detecting the organophosphonis compounds, such as a pesticides or a nerve agents is provided. The devices function by selectively binding an organophosphorous compound to a luminescent functionality-imprinted copolymer. The copolymers possess a securely bound luminescent lanthamide ion, such as Eu3+, in a coordination complex that has been templated for the chemical functionality.

Abstract: A sensing element in which a dye that changes in the light absorption characteristic of the visible region upon reaction with ozone gas is deposited in the pores of a porous material is prepared. A change in dye before and after exposing the sensing element to a measurement environment for a predetermined time is measured. The ozone gas amount in measurement target air is measured on the basis of the change in dye.

Abstract: A B-lymphocyte classifying method includes the steps of (1) preparing a measurement sample by mixing a blood sample with a lysing reagent to lyse erythrocytes and to shrink the B-lymphocytes in the blood sample, (2) letting the measurement sample flow through a flow cell of a flow cytometer, (3) radiating a light beam onto a cell in the measurement sample that is flowing through the flow cell, (4) detecting at least two scattered light emitted from the irradiated cell, (5) specifying a region of a B-lymphocyte cluster in accordance with the detected scattered light, and (6) counting the number of B-lymphocytes in the specified region.

Abstract: An improved elemental mercury analyzer utilizes a fluorescence assembly in combination with a fluorescence quenching reduction mechanism to detect the concentration of elemental mercury within an emission gas sample, via fluorescence of the mercury within the gas sample, while minimizing fluorescence quenching of the gas sample. In one arrangement, the analyzer contains the emission gas sample under a vacuum or negative pressure while detecting fluorescence of the elemental mercury within the emission gas sample. By performing fluorescence detection of the emission gas sample at reduced pressure relative to the pressure of the as-sampled emission gas, the analyzer reduces the number of particle collisions within the emission gas sample over a certain period of time. Such collisional deactivation, and/or the addition of oxygen depleted gas such as nitrogen to the gas sample, reduces fluorescence quenching of the emission gas sample, improving accuracy of detection of mercury.

Abstract: A microsphere-based analytic chemistry system is disclosed in which self-encoding microspheres having distinct characteristic optical response signatures to specific target analytes may be mixed together while the ability is retained to identify the sensor type and location of each sensor in a random dispersion of large numbers of such sensors in a sensor array using an optically interrogatable encoding scheme. An optical fiber bundle sensor is also disclosed in which individual microsphere sensors are disposed in microwells at a distal end of the fiber bundle and are optically coupled to discrete fibers or groups of fibers within the bundle. The identities of the individual sensors in the array are self-encoded by exposing the array to a reference analyte while illuminating the array with excitation light energy.

Abstract: The present method uses a spectrophotometric and/or ionisation detection device in which the gas to be analyzed and illuminated by a light source emitting in a range of wavelengths distinct from the one used for spectrophotometry so as to carry out a nephelometric and/or turbidimetric detection, the results of this detection being used to carry out an adjustment of the device for counting the particles and/or for determining the composition of these particles.

Abstract: A method of determining bias in a measurement of a constituent concentration level in a sample gas is provided. The method comprises establishing a sample gas flow from an emission stream into a sample gas line of an emissions monitoring system. The method further comprises removing water from the sample gas flow and cooling the sample gas flow to a temperature below about 41° F. to produce a cooled, dried sample gas flow. The constituent concentration level is then determined for the cooled, dried sample gas flow. The method further comprises introducing a span gas having a known span gas constituent concentration level into the sample gas flow to form a combined sample and span gas flow, the span gas being introduced at a desired span gas flow rate. The method still further comprises removing water from the combined sample and span gas and cooling the combined sample and span gas to a temperature below about 41° F. to produce a cooled, dried, combined sample and span gas flow.

Abstract: A gas detector includes a predetermined amount of a sensor material having at least one optical property which changes as a result of reaction with a target gas and a photometric device operable to measure the intensity of said at least one optical property of the sensor material. The reaction is such that there is a one-to-one relationship between the magnitude of the intensity of at least one optical property and the concentration of the target gas in the gas sample whereby the concentration of the target gas in the gas sample may be determined from the measured magnitude of the intensity of said at least one optical property after the passage of the predetermined volume of gas sample over the given area of sensor material.

Abstract: Molecularly imprinted polymer membranes for selectively collecting phosphate, nitrate and ferric ions are disclosed, prepared by copolymerizing a matrix monomer, cross-linking agent, ion imprinting complex, permeability agent and polymerization initiator, after which the ions of the ion imprinting complex are permeability agent are removed. The permeability agent creates channels in the membrane permitting the ion binding sites in the membrane to communicate with the exterior surface of the membrane.

Abstract: A method and system for performing low level sulfur UV fluorescence measures including an UV interference reduction system which removes or destroys interfering nitrogen oxides. The preferred nitrogen removal systems include introducing ozone into the system in sufficient quantities to destroy any produce NO and optionally a nitrogen sparge or similar nitrogen gas removal system.

Abstract: A method for measuring the concentration of harmful gases in flue gases through a heat-producing plant that includes a combustion space and a device located downstream of the combustion space, the device includes tubes, through which for instance water, steam or air may pass in order to be heated by heat transfer from flue gases formed during the combustion. In a region near the tube device, at least one beam of ultraviolet light is emitted from a light emitter at one side of a flue gas duct to a light receiver located at the opposite side of the duct, which light emitter is connected to a spectrometer cooperating with a computer unit, in which spectrometer the light is divided spectrally.

Abstract: A system for quickly and automatically extracting and analysing residual solvents is realised for operating directly in the premises where the packing materials are being manufactured, printed and/or laminated. The system provides for a single unit equipped with a display and a keyboard, and comprises an extraction (desorption) chamber (1), an analysis chamber with valves and separating columns, a detection system (17), and a data processing system (19). The extracting or desorption chamber comprises a desorption cell (1) for receiving a vial (36; 37) containing said sample, and means are provided to keep the inside of said cell (1) at a pressure higher that that of the surrounding environment until a new sample has been introduced into the cell, thus accomplishing a “washing” of cell for eliminating polluting solvents coming from the desorption of a preceding sample and/or solvents present in the surrounding environment.

Abstract: A method and an apparatus which continuously separate and measure mercury in an exhaust gas in accordance with each chemical conformation and display a measurement result in real time. According to the method and the apparatus, water-soluble mercury in a gas is absorbed into an absorption solution (7), the gas and the absorption solution (7) are then separated from each other, the water-soluble mercury in the absorption solution (7) is reduced to be converted into gaseous metal mercury and led to an analyzer (20), and metal mercury in the gas which is not absorbed into the absorption solution (7) is led to an analyzer (22) in the form of gas. As a result, the water-soluble mercury and the non-water-soluble mercury contained in the gas can be captured and measured/analyzed in respective measurement systems in accordance with each chemical conformation. In addition, a concentration of the metal mercury and that of the water-soluble mercury in the gas can be continuously monitored in real time.

Abstract: A lightweight and portable analyzer is provided. At least one component of the analyzer is made from a lightweight material, such as ABS. A manifold can have a plate and gas passages ultrasonically welded together. By having at least one component made from a lightweight material, the analyzer is lighter.

Abstract: An analyzer characterized by comprising a chip and a detector, wherein the chip is an organic polymer member having a fine capillary through which a fluid sample or a fluid sample and a fluid reagent flow and can perform a chemical reaction on the sample in the capillary without using a separate weighing means, and the detector is a photothermal conversion detector for measuring a physical quantity change such as a refractive index change caused by a partial temperature change of the sample and the reagent by applying an excitation light to a substance to be measured produced by the chemical reaction, thereby providing a small analyzer excellent in chip waste-disposal, capable of analyzing inexpensively, simply and in a short time and being suitable for a POC analysis.

Abstract: An apparatus for measuring the concentration of formaldehyde in an exhaust stream from turbines, internal combustion engines and the like, which apparatus includes a portable housing having a sample gas inlet through which a sample gas for analysis is introduced into the portable housing and an analysis system disposed in the portable housing suitable for analyzing the sample gas for the presence of formaldehyde in the sample gas.

Abstract: The invention herein provides for the detection of certain organic halogen-containing agents or toxicants such as sarin, chloropicrin, mustard gas, mustard chlorohydrin, phosgene, chlorine, soman, lewisite, diphosgene and others by, in one embodiment, first reacting the agents with superoxide free radical anion (.O{overscore (2)}) to produce light pulses which can be detected by a standard photon counter. The superoxide may be available from a dimethyl sulfoxide superoxide (.O{overscore (2)}) liquid solution, from lecithin coated beads charged with superoxide (.O{overscore (2)}) in a reaction vessel or from a quarternary ammonium ion exchange resin charged with superoxide anion (.O{overscore (2)}) in a reaction vessel.

Abstract: A chemochromic sensor includes multiple bi-directional LEDs, each optically aligned with one or more test areas. Each LED is used as both a light emitter when driven in forward bias, and as a light detector when driven in reverse bias. By alternating the bias on the LEDs, multi-way light measurements of the test area can be obtained.

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: This invention relates to an irreversible indicator for detecting oxidising agents, or in particular an oxygen indicator, comprising at least one redox-sensitive dyestuff, at least one semiconductor material and at least one electron donor. This indicator is activated by exposure to light of about 200-400 nm. The invention also relates to UV light detector.

Abstract: A single pass analyzer includes multiple infrared sensors, a catalytic converter, a scrubber and a thermal conductivity cell all coupled in series to provide a single pass (i.e., one sample) analyzer which allows for fast analysis, allows for the speciation of hydrogen samples, requires no purging between different sample types, utilizes a single carrier gas, and eliminates molecular sieves and Shutze converters. The resultant analyzer provides improved quicker results with less plumbing (i.e., gas conduits and valving) in a single instrument.

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: A method and apparatus is provided for detection of volatile products from a sample using a transducer which changes voltage as a function of contact of the volatile products with the transducer to produce a gas signature of the volatile products and a spectrophotometer to analyze the volatile products to produce a spectral footprint of the volatile products. The apparatus and method are used to detect spoilage of a biological material, such as a food. The apparatus is also used to detect microorganisms and by comparing the gas signature and spectral footprint to a library of gas signatures and spectral footprints, the apparatus enables identification of the microorganisms and in particular identification of pathogenic microorganisms.

Abstract: A sensing element in which a dye that changes in the light absorption characteristic of the visible region upon reaction with ozone gas is deposited in the pores of a porous material is prepared. A change in dye before and after exposing the sensing element to a measurement environment for a predetermined time is measured. The ozone gas amount in measurement target air is measured on the basis of the change in dye.

Abstract: Devices for measuring and detecting a wide variety of analytes, including polyatomic anions, such as organophosphorus pesticides and nerve agents are provided. The devices function by selectively binding an analyte to a luminescent functionality-imprinted copolymer. The copolymers possess a securely bound luminescent lanthanide ion, such as Eu3+, in a coordination complex that has been imprinted to bind the chemical functionality. Also provided are methods for producing the lanthanide-containing molecularly imprinted polymers of the invention.

Abstract: An anodic double layer gasochromic sensor structure for optical detection of hydrogen in improved response time and with improved optical absorption real time constants, comprising: a glass substrate; a tungsten-doped nickel oxide layer coated on the glass substrate; and a palladium layer coated on the tungsten-doped nickel oxide layer.

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 driver 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: An integrated mesopump-sensor suitable for disposition in two- and three-dimensional arrays having small dimensions is disclosed. One mesopump is formed of an electrostatically attractable flexible diaphragm disposed through cavities or pumping chambers formed between two opposing electrostatically chargeable material layers. Fluid is pumped through the chambers by sequentially moving the diaphragm toward the first chargeable layer, then towards the second chargeable layer, which can pull and push the fluid through a series of chambers, and past the sensor. One group of sensors utilizes multiple and varied chemoresistive sensors which can vary in resistance differently in response to the presence of various analytes. Another group of sensors utilizes chemo-fluorescent sensors that fluoresce in the presence of particular analytes.

Abstract: A hydrogen sensor, useful for trace hydrogen gas detection. The sensor involves providing a gas sample, generating modulated optical excitation sources, bringing the optical excitation source to the side of a metalized thin pyroelectric film, and detecting via a lock-in amplifier circuit the coherent differential signal resulting from thermoreflectance and thermoabsorptance changes in the film when exposed to hydrogen gas.

Abstract: A portable instrument for automatic collection and analysis of airborne lead concentrations in ambient air environments. Its improvements to the art of airborne lead detection and analysis permit the apparatus to analyze samples previously collected by personal monitors, for example, worn on the clothing of personnel working in contaminated sites. The apparatus also brings to the art of lead analysis a method of contaminant collection that ensures a greater capture efficiency of airborne contaminants, thereby increasing the accuracy of the instrument and its measurement capabilities while providing near real-time analysis and measurement in a portable self-contained battery-powered device. The apparatus also offers a remarkable improvement in the reduction of wastes incurred in the collection and analysis of airborne lead contaminants which is a novel method of concentrating the samples and recycling the analysis media used to concentrate and solubilize lead contaminants.

Abstract: An optical sensor is proposed for determining gases in gas mixtures, especially for determining one gas component in the air, having a sensitive layer exposed to the gas and having a device for detecting a change in an optical property of the sensitive layer. The sensitive layer of the sensor contains a phosphorus or nitrogen-containing base having numerous and/or long-chain alkyl groups for the pH adjustment of the sensitive layer.

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.