Abstract: The invention features methods and systems for detecting the presence of an energetic material in a sample in which the presence of the energetic material is unknown. The method includes the steps of: heating the sample; measuring heat flow between the sample and its surrounding environment, e.g., by using differential scanning calorimetry (DSC); and analyzing the measured heat flow between the sample and its surrounding environment. An exothermal peak in the measured heat flow indicates the presence of the energetic material in the sample. The system includes a thermal measuring apparatus for performing the heating and measuring steps, and an analyzer for detecting the presence of the energetic material based on the measured heat flow. The invention also features methods and systems for identifying contraband materials (e.g., explosives and drugs) by measuring the thermogram (e.g., by DSC) of a sample to be identified and comparing it to reference thermograms for known contraband materials.

Abstract: When a micro-heater heats fluid using an external driving current, an upstream thermopile 8 detects the temperature of the fluid before it is heated to produce a first temperature detected signal and a downstream thermopile 9 detects the temperature of the fluid before it is heated to produce a second temperature detected signal. The flow rate is computed based on the difference signal between both detected signals. A right thermopile 11 and a left thermopile 13, which are arranged in a direction orthogonal to the flow direction of the fluid, detect the temperature of the fluid to produce a right temperature detected signal and a left temperature detected signal. The property of the fluid is computed on these right and left temperature detected signals. The flow rate is corrected on the basis of the property thus computed. The flow rate of an object fluid for measurement can be accurately measured by a flow sensor whose output characteristic varies when the kind or composition of the fluid changes.

Abstract: A colorimeter has an absorber for absorbing radiation energy and converting the radiation energy into thermal energy. A resistor is connected to the absorber for converting thermal energy into an electrical signal. A membrane is connected to the resistor for controlling a thermal discharge from the resistor. A substrate is connected to the membrane and has a tri-layer structure comprised of an etching layer having a preselected thickness, an etching stop layer and a support substrate. The membrane is spaced-apart from a main surface of the etching stop layer by the preselected thickness of the etching layer.

Abstract: A nanocalorimeter array for detecting chemical reactions includes at least one thermal isolation region residing on a substrate. Each thermal isolation region includes at least one thermal equilibration region, within which resides a thermal measurement device connected to detection electronics.

Abstract: A water bath accommodating a calorimetric bomb (2) for measuring the combustion heat of substances with the aid of a calorimeter. The inner tank (3) is enclosed by an outer container (5) forming a water jacket and is shielded from the environment. If several measurements are conducted subsequently, the water found in the inner tank (3) and heated above its initial value through the combustion process taking place in connection with a previous measurement can be at least partially transferred into the outer container (5) with a second or other succeeding measurement prior to conducting it so that at least a part of the combustion heat of the preceding measurement can be used for heating up at least the water jacket in the outer container (5) in connection with the next measurement. Consequently, energy for tempering the water in the water jacket and/or in the water bath can be saved.

Abstract: The present invention provides a MEMS-based integrated particle identification system having a substrate, a magnetic structure, and a bioferrograph. The substrate includes a topside portion, backside portion and a flow system. The flow system includes a flow channel for accepting the flow of a stream of particles to identified. The magnetic structure is in physical communication with the topside and backside portions of the substrate and has at least two pole pieces. A plurality of pole piece embodiments are provided for generating a magnetic field that acts on magnetically susceptible particles in the flow stream. The bioferrograph has at least one sensor for identifying the presence and quantity of magnetically susceptible particles. A plurality of sensor embodiments are also provided.

Abstract: An improved phase transition analyzer (22) is provided which greatly facilitates analysis of composite mixtures such as protein and starch-containing extrudate mixtures to give valuable information about the mixture, e.g., glass transition and melt transition temperatures, Tg and Tm. The analyzer (22) includes a body (74) having a chamber (192) adapted to receive a sample (196) of a material to be analyzed, together with a force-applying assembly (34-40, 68) operable to apply a compressive force to the sample 196 and a heating assembly (96, 138). In order to determine Tg, the sample (196) is progressively heated under sustained exertion of compaction force with chamber (192) closed. The sample (196) is compacted and the volume of chamber (192) correspondingly decreases, this being sensed by movement of a portion (34, 36) of the force-applying assembly (34-40, 68) by a displacement transducer (44).

Abstract: A calorimeter that measures heat release rates of very small samples (on the order of one to 10 milligrams) without the need to separately and simultaneously measure the mass loss rate of the sample and the heat of combustion of the fuel gases produced during the fuel generation process. The sample is thermally decomposed in a small volume pyrolysis chamber. The resulting fuel gases are immedediately swept by an inert gas stream from the pyrolysis chamber into a combustion furnace in a plug-like flow. This plug flow substantially synchronizes the emerging fuel gases with the mass loss rate of the sample. Oxygen is metered into the fuel gas stream just before it enters the combustion furnace where the fuel gases are completely oxidized. The effluent from the furnace is analyzed to determine the amount of oxygen consumed per unit time and the heat release rate is computed without the need to separately measure the mass loss rate of the sample.

Abstract: The present invention relates to a device for measuring the concentration of hydrogen in a gaseous mixture and in particular in the air constituting, for example, the atmosphere inside a closed premises. This device comprises a sensor in contact with a gaseous mixture, the sensor being linked to calculating and display function. The sensor comprises a catalyst capable of provoking an exothermic reaction with the hydrogen contained in the gaseous mixture, a conducting function fixed to the catalyst for transferring essentially by conduction the thermal energy release by the reaction from the catalyst to a cold point, a function for measuring the temperature T1 of the catalyst and the temperature T2 of the cold point being linked to the function for calculating the value of the molar concentration of hydrogen in a gaseous mixture from the temperature gradient measured T1-T2.

Abstract: Apparatus and methods for performing calorimetry. The apparatus include optical devices for detecting thermal processes and multiwell sample plates for supporting samples for use with such optical devices. The methods include measurement strategies and data processing techniques for reducing noise in measurements of thermal processes. The apparatus and methods may be particularly suitable for extracting thermal data from small differential measurements made using an infrared camera and for monitoring chemical and physiological processes.

Abstract: A method and apparatus using thermomechanical means for signalling the concentration of a reactive gas is disclosed. The thermomechanical means uses movement of a mechanical member to produce a signal corresponding to the concentration of the reactive gas in a gas stream. The method and apparatus may include means for converting a specific gas in a gas stream to a reactive gas. The apparatus may then provide an analog readout of the concentration of the specific gas.

Abstract: A method and apparatus are provided for detecting and monitoring micro-volumetric enthalpic changes caused by molecular reactions. Micro-machining techniques are used to create very small thermally isolated masses incorporating temperature-sensitive circuitry. The thermally isolated masses are provided with a molecular layer or coating, and the temperature-sensitive circuitry provides an indication when the molecules of the coating are involved in an enthalpic reaction. The thermally isolated masses may be provided singly or in arrays and, in the latter case, the molecular coatings may differ to provide qualitative and/or quantitative assays of a substance.

Abstract: A micro flow system is provided for separating particles, comprising a microfabricated member having a flow channel (5) defined therein for guiding a flow of a fluid containing the particles through the flow channel, first inlet means (2) positioned at one end of the flow channel for entering the fluid into the flow channel, first outlet means (7) positioned at the other end of the flow channel for discharging the fluid from the flow channel, the flow of the fluid containing the particles being controlled in such a way that one particle at the time passes a cross section of the flow channel, the member being positioned in a field that is substantially perpendicular to a longitudinal axis of the flow channel so that particles residing in the flow channel and being susceptible to the filed across the flow channel are deflected in the direction of the field.

Abstract: Apparatus and methods for performing calorimetry. The apparatus include optical devices for detecting thermal processes and multiwell sample plates for supporting samples for use with such optical devices. The methods include measurement strategies and data processing techniques for reducing noise in measurements of thermal processes. The apparatus and methods may be particularly suitable for extracting thermal data from small differential measurements made using an infrared camera and for monitoring chemical and physiological processes.

Abstract: Apparatus and methods for performing calorimetry. The apparatus include optical devices for detecting thermal processes and multiwell sample plates for supporting samples for use with such optical devices. The methods include measurement strategies and data processing techniques for reducing noise in measurements of thermal processes. The apparatus and methods may be particularly suitable for extracting thermal data from small differential measurements made using an infrared camera and for monitoring chemical and physiological processes.

Abstract: A calorimeter that measures heat release rates of very small samples (on the order of one to 10 milligrams) without the need to separately and simultaneously measure the mass loss rate of the sample and the heat of combustion of the fuel gases produced during the fuel generation process. The sample is thermally decomposed in a small volume pyrolysis chamber. The resulting fuel gases are immediately swept by an inert gas stream from the pyrolysis chamber into a combustion furnace in a plug-like flow. This plug flow substantially synchronizes the emerging fuel gases with the mass loss rate of the sample. Oxygen is metered into the fuel gas stream just before it enters the combustion furnace where the fuel gases are completely oxidized.

Abstract: The invention features methods and systems for detecting the presence of an energetic material in a sample in which the presence of the energetic material is unknown. The method includes the steps of: heating the sample; measuring heat flow between the sample and its surrounding environment, e.g., by using differential scanning calorimetry (DSC); and analyzing the measured heat flow between the sample and its surrounding environment. An exothermal peak in the measured heat flow indicates the presence of the energetic material in the sample. The system includes a thermal measuring apparatus for performing the heating and measuring steps, and an analyzer for detecting the presence of the energetic material based on the measured heat flow. The invention also features methods and systems for identifying contraband materials (e.g., explosives and drugs) by measuring the thermogram (e.g., by DSC) of a sample to be identified and comparing it to reference thermograms for known contraband materials.

Abstract: Provided are, among other things, devices for and methods for performing thermal signature assays on a two or more samples in an array, using active/control base thermopiles, the method comprising: [a] performing a heat transfer to the two or more samples in each of a two or more containers, using at least one base thermopile in thermal communication with the two or more containers; and [b] determining a total heat transferred to the samples by the base thermopile in step [a]; and [c] sensing in real time a temperature difference between a first sample and a second sample of the two or more samples resulting from performing step [a].

Abstract: A water bath accommodating a calorimetric bomb (2) for measuring the combustion heat of substances with the aid of a calorimeter. The inner tank (3) is enclosed by an outer container (5) forming a water jacket and is shielded from the environment. If several measurements are conducted subsequently, the water found in the inner tank (3) and heated above its initial value through the combustion process taking place in connection with a previous measurement can be at least partially transferred into the outer container (5) with a second or other succeeding measurement prior to conducting it so that at least a part of the combustion heat of the preceding measurement can be used for heating up at least the water jacket in the outer container (5) in connection with the next measurement. Consequently, energy for tempering the water in the water jacket and/or in the water bath can be saved.

Abstract: The oxygen and carbon dioxide content of expired respiratory gas is determined by measuring the mass and volume of the expired breath. From the composition of the inspired gas which may either be assumed or measured, the mass of the inspired volume may be determined, and since the inspired and expired breaths contain the same mass of nitrogen, the oxygen and carbon dioxide content of the expired breath may be determined. Measurements of temperature and humidity may be required to account for temperature and humidity changes between the inhalation and the exhalation or the inhaled gas may be adjusted in temperature and humidity to equalize the inhaled and exhaled temperature and humidity conditions. The mass and volume of the expiration and the volume mass of the inhalations are determined by an ultrasonic transit time system and a gas density sensor.

Abstract: Ceramic liners for use with closed bomb devices are disclosed. The closed bomb devices measure performance properties of energetic materials, such as solid propellant, explosive, and pyrotechnic formulations. The closed bomb devices include a body and a ceramic liner. Alumina silicate and boron nitride are two currently preferred ceramic liner materials which have low compressibility, low thermal conductivity, and excellent durability.

Abstract: A method and apparatus are disclosed for analyzing the aggregate content of asphalt-aggregate compositions. The method includes placing a preheated, preweighed container carrying a sample of an asphalt-aggregate composition into a preheated furnace with the preheated furnace being warmer than the preheated sample, continuing to heat the furnace while drawing air through the furnace at a rate that avoids impeding the heating of the furnace or the sample until the sample in the container reaches its combustion temperature and the combustion of the sample becomes exothermic, initiating a second draw of air around rather than through the furnace to moderate the exterior temperature of the furnace, accelerating the draw through the furnace to increase the rate of combustion of the exothermic reaction, and reweighing the container and sample after combustion is complete.

Abstract: Method for specific detection of one or more analytes in a sample. The method includes specifically associating any one or more analytes in the sample with a scattered-light detectable particle, illuminating any particle associated with the analytes with light under conditions which produce scattered light from the particle and in which light scattered from one or more particles can be detected by a human eye with less than 500 times magnification and without electronic amplification. The method also includes detecting the light scattered by any such particles under those conditions as a measure of the presence of the analytes.

Abstract: A method of operating a calorimetric gas sensor by modulating its operating temperature includes the steps of heating a sensing element and a reference element of a calorimetric gas sensor to a first temperature between a predetermined minimum temperature and a light-off temperature of the sensing element, modulating the heating of the sensing element and reference element between a second temperature above the light-off temperature and the first temperature to produce an alternating current (AC) output, and measuring the AC sensor output of the frequency of modulation.

Abstract: A calorimeter sensor apparatus is developed utilizing microcantilevered spring elements for detecting thermal changes within a sample containing biomolecules which undergo chemical and biochemical reactions. The spring element includes a bimaterial layer of chemicals on a coated region on at least one surface of the microcantilever. The chemicals generate a differential thermal stress across the surface upon reaction of the chemicals with an analyte or biomolecules within the sample due to the heat of chemical reactions in the sample placed on the coated region. The thermal stress across the spring element surface creates mechanical bending of the microcantilever. The spring element has a low thermal mass to allow detection and measuring of heat transfers associated with chemical and biochemical reactions within a sample placed on or near the coated region. A second surface may have a different material, or the second surface and body of microcantilever may be of an inert composition.

Abstract: A differential scanning microcalorimeter produced on a silicon chip enables microscopic scanning calorimetry measurements of small samples and thin films. The chip may be fabricated using standard CMOS processes. The microcalorimeter includes a reference zone and a sample zone. The reference and sample zones may be at opposite ends of a suspended platform or may reside on separate platforms. An integrated polysilicon heater provides heat to each zone. A thermopile consisting of a succession of thermocouple junctions generates a voltage representing the temperature difference between the reference and sample zones. Temperature differences between the zones provide information about the chemical reactions and phase transitions that occur in a sample placed in the sample zone.

Abstract: A differential calorimetric gas sensor (10) which includes a sensing element (12) having a catalytic layer (14) disposed on a multi-layered substrate (26). Catalytic layer (14) includes an active catalyst region (14a) which oxidizes total combustibles within an exhaust gas stream and a reference catalyst region (14b) which oxidizes selective combustibles within the exhaust gas stream. An electrochemical oxygen source (18) is disposed on an opposite side of multi-layer substrate (26) from sensing element (12). An oxygen sensor cell (170) may be incorporated into electrochemical oxygen source (18). The multi-layered substrate (26) includes a plurality of overlaying insulating layers in which an intermediate layer (60) and a bottom layer (64) support primary heaters (58, 62), and in which another intermediate layer (52) supports compensation heaters (50a, 50b).

Abstract: A calorimeter for measuring flammability parameters of materials using only milligram sample quantities. The thermochemical and thermophysical processes associated with the flaming combustion of solids are reproduced in the device through rapid anaerobic pyrolysis in a thermogravimetric analyzer. Volatile anaerobic thermal decomposition products are swept from the pyrolysis chamber by an inert gas and combined with excess oxygen in a combustion chamber maintained at several hundred degrees Centigrade to simulate the combustion reactions which occur in a well ventilated diffusion flame. Mass loss is measured continuously during the process and heat release rate is calculated from the oxygen consumed from the gas stream.

Abstract: A differential calorimeter includes sample and reference cells, a thermal shield surrounding these cells, heating devices thermally coupled to the thermal shield and the cells, a temperature monitoring system for monitoring temperature of the shield, cell temperatures and temperature differentials between the cells and the shield, and a control system. The control system has input lines to receive signals from the temperature sensors and output lines connected to the heating devices. The control system is configured to generate output signals for control of heating devices. A gain setting and scan rate are selected by means of a user interface. The output control signals are functions of input temperature signals and the user-selected gain setting, and also functions of input temperature signals and the user-selected scan rate using a mapping function stored in memory.

Abstract: In a test strip package having a plurality of test strips (20), each of which test strips has a test field (32) for evaluation by an optical measuring mechanism of a measuring device and including a container (12) for receiving the test strips (20) the container (12) is made as a rectangular closed flat envelope (12) for receiving a rectangular card (18), with the card (18) consisting of a plurality of test strips (20) which are separable from one another along tear lines (22).

Abstract: A method and apparatus is provided for modulating flux of combustibles reacting with oxygen impinging on a calorimetric gas sensor. The method includes the steps of enclosing a sensing element and a reference element of a calorimetric gas sensor with an apparatus having at least one aperture to allow combustibles to enter and impinge on the sensing element and reference element, periodically restricting the aperture of the apparatus to modulate the flux of combustibles entering at a predetermined frequency to produce an AC output signal from the calorimetric gas sensor, and measuring the sensor output at the frequency at which the aperture is restricted.

Abstract: A modified noble metal catalyst based calorimetric sensor for sensing non-methane hydrocarbons in an automotive exhaust gas stream includes a first sensing element (105) with an output that provides a signal (111) indicative of a concentration of indicative of non-methane hydrocarbons, hydrogen (H.sub.2), and carbon monoxide (CO). A compensating sensing element (107) has an output that provides a compensating signal (113) indicative of a concentration of hydrogen (H.sub.2) and carbon monoxide (CO). A circuit for combining the signal and the compensating signal provides a combined signal indicative of a measure of non-methane hydrocarbons in the automotive exhaust gas stream.

Abstract: A waveguide binding assay method involves detecting the scattering of light directed into the waveguide, the scattering being the result of scattering labels specifically bound to the waveguide within the penetration depth of an evanescent wave. The waveguide may be transparent plastic or glass and the binding is typically by oligonucleotide hybridization or immunological capture. Light scattering labels include colloidal metals or non-metals, including gold, selenium and latex. A light absorbing member consisting of dye or concentrated particles may also be employed to enhance signal. Real-time binding and dissociation can be monitored visually or by video imaging, such as with a CCD camera and frame grabber software. Hybridization mismatches of as few as one base can be distinguished by real-time melting curves.

Abstract: A catalytic differential gas combustible microcalorimeter sensor for monitoring the exhaust gas conversion for monitoring the exhaust gas conversion efficiency of a catalytic converter. The catalytic calorimetric sensor disclosed includes a sol-gel processed washcoat and sol-processed catalytically active metal particles. Sol-gel processing creates a washcoat with high surface area and controlled porosity which increases the sensitivity, durability, and reproducibility of the resultant sensor.

Abstract: A calorimeter includes sample and reference cells, a thermal shield surrounding these cells, a heating device thermally coupled to the thermal shield, temperature sensors for monitoring a temperature of the shield and a temperature differential between the shield and the cells, and a control system. The control system has an output line connected to the heating device and input lines to receive signals from the temperature sensors. The control system is configured to generate on its output line an output signal which is a function of both the input signals received on its input lines.

Abstract: Apparatus for measuring heat capacity of a sample where a series of measurements are taken in succession comprises a sample holder in which a sample to be measured is disposed, a temperature sensor and sample heater for providing a heat pulse thermally connected to the sample, and an adiabatic heat shield in which the sample holder is positioned and including an electrical heater. An electrical power supply device provides an electrical power output to the sample heater to generate a heat pulse. The electrical power from a power source to the heat shield heater is adjusted by a control device, if necessary, from one measurement to the next in response to a sample temperature-versus-time change determined before and after a previous heat pulse to provide a subsequent sample temperature-versus-time change that is substantially linear before and after the subsequent heat pulse.

Abstract: The invention relates to a process and device for detecting surface plasmons. According to the invention, the surface plasmons are excited by radiation energy in a thin material layer and, on decaying, release heat producing a temperature rise in the material layer. To simplify the detection of the surface plasmons technically and at the same time especially to attain a good lateral and temporal resolution, an electro-thermal sensor allocated to the material layer measures a parameter of the layer in the irradiation region at the same time as the temperature rise and emits a signal corresponding to that parameter. An ultra-thin-film thermometer is, in particular, used to detect the surface plasmons. The process and device are applicable especially to the field of bio and immuno sensory analysis.

Abstract: A collapsible treadmill includes a base body and handle bars. The base body supports such basic components as an electric motor, front and rear shafts, a tread belt, a tread board. The base body includes a U-shaped frame and a rectangular main frame. The U-shaped frame is provided with pivot seats at their ends, while the main frame is provided with corresponding pivot plates at both sides of its front end. The U-shaped frame and the main frame are pivotally joined by screw bolts connecting the pivot seats and the pivot plates such that the main frame may be folded upwardly to rest between the handle bars when the treadmill is not in use so as to reduce floor-occupying space.

Abstract: A folding device for treadmill, particularly a easy and ready-to-fold folding device to fold handle frame on treadmill so that the handle frame can be folded to the surface of treadmill body to minimize packing volume and transportation cost as well as to save space requirement for storage.

Abstract: A multi-purpose exercise machine is composed of a grip frame and a treading frame. The grip frame is of a U-shaped construction and is fastened at both ends thereof with the treading frame which can be folded to join with the grip frame so as to reduce the volume of the exercise machine for easy storage and shipping. The treading frame is provided with a plurality of rolling cylinders capable of affording an exerciser ther massaging exercise, the jogging exercise, and the walking exercise.

Abstract: A pulsed measurement technique for calorimetric sensors provides a short current pulse through catalyzed and inert sensor elements to minimize self heating while providing for sensor resistance measurement, so that a determination of the level of catalytic activity at the surface of the catalyzed element may be made for sensing the concentration of combustible elements of automotive internal combustion engine exhaust gas. Exhaust gas temperature measurement is provided by monitoring the inert element resistance. Exhaust gas flow rate measurement is provided by heating the inert element for a short heating period, and then removing the heat source while monitoring the time rate of return to the known initial inert element temperature.

Abstract: Disclosed is a method to make and an apparatus for monitoring the exhaust gas conversion efficiency of a catalytic converter. The catalytic calorimetric sensor disclosed includes a sol-gel processed washcoat and sol-processed catalytically active metal particles. Sol-gel processing creates a washcoat with high surface area and controlled porosity which increases the sensitivity, durability, and reproducibility of the resultant sensor.

Abstract: A method for measuring the heat of reaction resulting from the mixture of a plurality of reagents comprising the steps of providing a first reagent into a compartment; providing a second reagent into the compartment so as to mix the second reagent with the first reagent within the compartment; withdrawing a predetermined amount of the mixed first and second reagents from the compartment; depositing the withdrawn predetermined amount of the mixed first and second reagents back into the compartment; generating electrical signals based on the heat of reaction of the mixed first and second reagents; and deriving data indicative of the heat of reaction based on the electrical signals.

Abstract: A cabinet has a tread base rotatably connected to be oriented in an exercise position extending outwardly and in a stored position extending inwardly secured within the enclosure of the cabinet. The underside of the tread base may be configured to provide a suitable aesthetic exterior surface. A latching arrangement is provided to secure the tread base within the enclosure in the second or stored position. Elevation structure and motor structure are provided to elevate the tread base when in the first position and to power the endless belt of the tread base when in the first position. The elevation structure may be operated to vary the inclination of the tread base when in the first position. The underside of the tread base has a decorative panel and functions as a door for the cabinet. The elevation structure may include an electrically driven rack and pinion as well as a gas cylinder system.

Abstract: A calorimetric measuring apparatus is provided with a decomposition vessel whose interior is configured as a reaction chamber and which can be tightly sealed, the decomposition vessel being removably arranged inside a jacket, and having at least one temperature sensor for measuring the temperature reached inside the decomposition vessel. Characteristic of the measuring apparatus is that the jacket has a measuring vessel which accommodates the decomposition vessel; at least some areas of the wall zone of this measuring vessel comprise a heat-conductive material; the inner walls of this measuring vessel are spaced from the outer walls of the decomposition vessel, thereby forming an interspace in which a gaseous intermediate medium is provided; and the measuring apparatus has at least a second temperature sensor for measuring the temperature change establishing itself in the heat-conductive wall zone of the measuring vessel.

Abstract: The process of preparing higher aluminum alkyls by olefin chain growth on alkyl aluminum is improved by using on-line flow-through calorimetry to determine the aluminum concentration of a process stream, such as the aluminum alkyl feed stream, by reacting a sample portion of the process stream with a molar excess of alcohol and measuring the change in temperature. The aluminum concentration of the stream can then be adjusted as required to maintain it within a selected range.

Abstract: A flow cell for calorimetric measurements comprises a body (2) with at least one flow channel (3), which extends between an inlet opening (4) and an outlet opening (5), and a thermoelectric detector (16) for monitoring temperature changes, which occur during chemical or biochemical processes in a measuring volume (17). The measuring volume (17) is arranged in close vicinity of the outlet opening (5). The body (2) of the flow cell (1) has a good thermal conductivity of a magnitude such, that a fluid flowing through the flow channel (3) is thermostatizised prior to entering the measuring volume (17) solely by flowing through the flow channel (3) and free of any external thermostatization means. Thus, a flow cell is provided, which is capable of self-thermostatizing a fluid flowing therethrough.

Abstract: A method is provided for evaluating the catalytic activity of carbonaceous chars via the decomposition of hydrogen peroxide in contact with such materials. In this method the rise in temperature occasioned by the decomposition of hydrogen peroxide under essentially adiabatic conditions is monitored as a function of time. By use of this method, carbonaceous chars having high catalytic activities may be rapidly and conveniently identified.

Abstract: A gas sensor for measuring gas constituents, particularly exhaust gas constituents for an internal combustion engine, comprising a pair of polysilicon plates, each plate supporting a pair of resistors, one serving as a heater and the other as a thermometer, one plate being coated with a catalyst to promote combustion of unburned combustible gas constituents, wherein provision is made for reducing temperature gradients across the plates and for effecting temperature uniformity of the catalyst while maintaining a high degree of structural integrity.

Abstract: This invention is a process for detecting low concentration levels of sulfur oxides (SO.sub.2) in a flowing gas stream (typically a combustion exhaust gas stream) and a catalytic SO.sub.2 sensor system which may be used in that process.