Abstract: Disclosed are a perovskite compound, a method for producing the perovskite compound, a catalyst for a fuel cell including the perovskite compound, and a method for producing the catalyst. The perovskite compound overcomes the low stability of palladium due to its perovskite structural properties. Therefore, the perovskite compound can be used as a catalyst material for a fuel cell. In addition, the use of palladium in the catalyst instead of expensive platinum leads to an improvement in the price competitiveness of fuel cells. The catalyst is highly durable and catalytically active due to its perovskite structure.

Abstract: A laminated microfluidic device is described that includes an internal microchannel formed from laminating individual layers of the laminated microfluidic device to each other. The laminated microfluidic device also includes a first port, a second port, a third port, and a fourth port each fluidically coupled to the internal microchannel. The laminated microfluidic device permits flow of sample into the laminated microfluidic device through the first port. The laminated microfluidic device fluidically couples to an external pressure source through the second port. The laminated microfluidic device permits the flow of the sample to a first component fluidically coupled to the third port and to a second component fluidically coupled to the fourth port depending on pressure within the internal microchannel of the laminated microfluidic device.

Abstract: Amperometric ceramic electrochemical cells comprise, in one embodiment, an electrolyte layer, a sensing electrode layer comprising a ceramic phase and a metallic phase, and a counter electrode layer, wherein the cell is operable in an oxidizing atmosphere and under an applied bias to exhibit enhanced reduction of oxygen molecules at the sensing electrode in the presence of one or more target gases such as nitrogen oxides (NOX) or NH3 and a resulting increase in oxygen ion flux through the cell. In another embodiment, amperometric ceramic electrochemical cells comprise an electrolyte layer comprising a continuous network of a first material which is ionically conducting at an operating temperature of about 200 to 550° C.; a counter electrode layer comprising a continuous network of a second material which is electrically conductive at an operating temperature of about 200 to 550° C.

Abstract: A gas sensor including a reduction section (18) for reducing NO2 contained in exhaust gas to NO. The reduction section (18) is provided on the upstream side of a first diffusion resistor section (103) which limits the flow of the exhaust gas into a first measurement chamber (101). When NOX passes through the first diffusion resistor section (103), NO2 which has a greater molecular weight than NO has a lower degree of diffusion. Since NO2 is reduced to NO at the reduction section (18), the exhaust gas passing through the first diffusion resistor section (103) hardly contains NO2. Therefore, the speed of flow of NOX through the first diffusion resistor section (103) is not limited by NO2, whereby sensitivity for detection of NOX can be improved.

Abstract: Disclosed is a gas sensor, particularly a lambda probe, for determining the oxygen concentration in the exhaust gas of an internal combustion engine that is operated using a fuel-air mixture. Said gas sensor comprises a pump cell with an outer electrode that is exposed to the exhaust gas, an inner electrode located in a measuring chamber which is separated from the exhaust gas by means of a first diffusion barrier, and an electronic circuit for generating a voltage applied between the outer electrode and the inner electrode as well as for measuring and evaluating a pump current that is generated in said process in order to draw a conclusion therefrom about the composition of the fuel-air mixture.

Abstract: A method of processing a sensor element includes the steps of: (a) preparing a gas atmosphere containing hydrocarbon, having an air-fuel ratio of 0.80 to 0.9999, and having a small amount of oxidizing gas added thereto; and (b) subjecting a sensor element to a heat treatment in the gas atmosphere at a temperature of 500° C. or higher for 15 minutes or longer. The sensor element includes an electrochemical pumping cell constituted of an oxygen-ion conductive solid electrolyte and an electrode having a NOx reduction ability. A NOx gas in a measurement gas is reduced or decomposed in the electrode. A NOx concentration in the measurement gas is obtained based on a current which flows in the electrochemical pumping cell at a time of the reduction or decomposition.

Abstract: A gas sensor element includes a base member comprising a plurality of laminated solid electrolyte layers, and having a space that communicates with the outside of the gas sensor element and allows introduction of the gas to be measured into the gas sensor element, and a porous measurement electrode that is formed on a surface of the space inside the base member, and is covered with a porous measurement electrode protective layer, wherein an average pore size A of the measurement electrode and an average pore size B of the measurement electrode protective layer satisfy the relationship “0.05?B/A?0.9”, the measurement electrode has an average pore size of 0.5 to 15 ?m, and the measurement electrode protective layer has an average pore size of 0.05 to 9 ?m, a porosity of 5 to 50%, and a thickness of 10 to 200 ?m.

Abstract: Provided is a method for accurately quantifying a chemical substance contained in a sample solution at a significantly low concentration of not more than 1×10?8 M. A measurement system used for the method includes a counter electrode 13, a first reference electrode 12, a first working electrode 11a, a second working electrode 11b, a second reference electrode 14 and a gel-coated electrode 15. The gel-coated electrode 15 is electrically equivalent to the second working electrode 11b. The gel-coated electrode 15 comprises an electrode body 31 and a gel 34. The surface of the electrode body 31 is coated with the gel 34. The gel 34 contains a standard electrolyte and an ionic liquid. The gel 34 contains no water. The ionic liquid is hydrophobic and nonvolatile. The ionic liquid is composed of a cation and an anion. The standard electrolyte is composed of the cation and a halide ion.

Abstract: A gas sensor (1a) having a laminate including an alumina substrate (11) having a heating resister (115) embedded in the alumina substrate (11); a first oxygen-ion conductive solid electrolyte layer (131) containing zirconia and alumina and partly constituting an oxygen-detecting cell (13) and the first solid electrolyte layer (131) being laminated with said alumina substrate (11); a second oxygen-ion conductive solid electrolyte layer (121) containing zirconia and alumina and partly constituting an oxygen-pumping cell (12); an ion-leakage preventing ceramic spacer (143) for preventing oxygen-ions from leaking from the second oxygen-ion conductive solid electrolyte layer (121) to the first oxygen-ion conductive solid electrolyte layer (131), the spacer (143) being laminated between the first and second oxygen-ion conductive solid electrolyte layers (131, 121); and a gas-diffusion space (141) formed between an electrode (133) of the oxygen-detecting cell (13) and an electrodes (126) of the oxygen-pumping cell (

Abstract: There is provided a gas sensor element, including a solid electrolyte layer, a pair of sensor electrodes arranged on a front side of the solid electrolyte layer, a pair of sensor leads arranged on a rear side of the solid electrolyte layer and connected to the respective sensor electrodes; and insulating layers, one of which is arranged between one of the sensor leads and the solid electrolyte layer and the other of which is arranged between the other sensor lead and the solid electrolyte layer. The sensor electrodes have rear end portions located on the insulating layers and overlapping front end portions of the sensor leads, respectively. The sensor leads are denser than the sensor electrodes and have front ends located in the same positions as or positions rear of front ends of the insulating layers, respectively. There is also provided a gas sensor with such a gas sensor element.

Abstract: A primary pump current is directed through a primary electrochemical cell system between first and second constant primary pump currents to direct a first ion flow into and out from a shared measuring chamber. A first output signal generated by the primary electrochemical cell system in accordance with a first ion concentration within the shared measuring chamber is detected. A second output signal generated by a secondary electrochemical cell system in accordance with a second ion concentration within the shared measuring chamber is also detected. Based on a relationship between the first and second output signals, a secondary pump current is directed through the secondary electrochemical cell system between first and second constant secondary pump currents to direct a second ion flow into and out from the shared measuring chamber.

Abstract: A method of manufacturing an exhaust gas sensor that includes positioning at least a portion of a subassembly of the exhaust gas sensor in a mold fixture, overmolding at least a portion of the subassembly with a ceramic material, and removing the overmolded subassembly from the mold fixture.

Abstract: A sealing portion is formed of a calcined body that is made by calcining a powder compact of a spherically-shaped granulated powder that is selected from the group consisting of alumina, aluminum titanate and cordierite. Anisotropy in physical properties is less likely to occur in the powder compact, because these ceramics are not only good in terms of thermal stability but also their spherically-shaped granulated powders are less likely to be oriented at the time of powder compacting. Therefore, the sealing portion comes to have a long longevity, because slippages between the particles are less likely to occur even when thermal histories are applied thereto, and because it can maintain the gas sealing property stably for a long period of time.

Abstract: A gas sensor contains a sensor element for detecting the concentration of a particular gas component in a measurement gas and a housing for supporting the sensor element inside, and the sensor element has a rectangular solid structure of a solid electrolyte body containing a ceramic material. In the gas sensor, four edges of the solid electrolyte body are beveled over the entire length thereof to form eleventh to fourteenth chamfered portions corresponding to the four edges.

Abstract: A gas sensor includes a gas sensor element. The gas sensor element includes a first detection chamber; a first oxygen pumping cell including a first solid electrolyte body and a pair of first electrodes; a second detection chamber; a second oxygen pumping cell including a second solid electrolyte body and a pair of second electrodes; and an oxygen-concentration sensing cell including a third solid electrolyte body and a pair of third electrodes. A sensing electrode of the third electrodes is disposed downstream beyond a first inner electrode of the first electrodes relative to a gas flow direction. A cross-sectional area of a space of the first detection chamber which faces the first inner electrode falls within a range from 0.03 mm2 to 0.22 mm2.

Abstract: There is provided a control device for a gas sensor. The gas sensor is formed with first and second oxygen pumping cells to define first and second measurement chambers. Under the control of the sensor control device, the first and second oxygen pumping cells effect oxygen pumping actions against the first and second measurement chambers, respectively. The sensor control device is configured to detect currents through the first and second oxygen pumping cells, calculate a correction coefficient by comparison of a detection value of the first oxygen pumping cell current at a known oxygen concentration period with a previously stored reference value, correct the first oxygen pumping cell current by the correction coefficient and determine the concentration of nitrogen oxide in the gas under measurement based on the corrected first oxygen pumping cell current and the detected second oxygen pumping cell current.

Abstract: There is provided a control apparatus for a gas sensor, which has a sensor element equipped with first and second oxygen pumping cells. The sensor control apparatus is configured to drive the first oxygen pumping cell to adjust the oxygen concentration of gas under measurement, drive the second oxygen pumping cell to produce a flow of electric current according to the amount of oxygen pumped out of the oxygen concentration adjusted gas by the second oxygen pumping cell, perform specific drive control to control the amount of oxygen pumped by the second oxygen pumping cell to a predetermined level after startup of the sensor element and before the application of the drive voltage between the electrodes of the second oxygen pumping cell.

Abstract: There is provided a gas sensor, which includes a sensor element extending axially of the gas sensor and having a gas sensing portion at a front end thereof and an electrode portion at a rear end thereof, a cylindrical metal shell retaining therein the sensor element with the gas sensing portion and the electrode portion protruding from front and rear ends of the metal shell, respectively, and having a flange portion and a rear end portion located on a rear side of the flange portion, a cylindrical protection cover having a front end fitted onto the rear end portion of the metal shell so as to cover the electrode portion and a weld joint through which the entire circumference of the front end of the protection cover is joined through the metal shell. The weld joint extends from an end face of the protection cover to the metal shell.

Abstract: An electrode for superoxide anions which contains a conductive component and, superimposed on a surface thereof, a film resulting from electrolytic polymerization of a metal thiofurylporphyrin/axial ligand complex; and a sensor for measuring a superoxide anion concentration including the same. The electrode for superoxide anions can prevent poisoning by a catalyst poison such as hydrogen peroxide. Accordingly, in any of in vitro or in vivo environments, this electrode for superoxide anions enables detection of superoxide anion radicals without suffering any influence from a catalyst poison such as hydrogen peroxide. Moreover, quantitative assay of superoxide anions can be performed with this electrode for superoxide anion in combination with a counter electrode or a reference electrode. Thus, this electrode for superoxide anions can find wide applicability in various fields.

Abstract: A gas sensor controller 190 stops an operation of pumping in or out oxygen that is being performed by a first pump cell 111 in a state that the oxygen concentration (oxygen partial pressure) of a gas to be measured is equal to a status judgment reference value (20%). The gas sensor controller 190 calculates an oxygen pressure in a second measurement chamber 161 on the basis of a second pump current Ip2. If the oxygen pressure in the second measurement chamber 161 is equal to a deterioration judgment reference value, the gas sensor controller 190 judges that the second pump cell 113 is in a normal state. If the oxygen pressure in the second measurement chamber 161 is different from the deterioration judgment reference value, the gas sensor controller 190 judges that the second pump cell 113 is in a deteriorated state.

Abstract: A sensor control device for controlling a current application state of a gas sensor element when measuring a specific gas component concentration in a gas to be measured using the gas sensor element, which sensor control device includes: at least one cell having a solid electrolyte body and a pair of electrodes; a sensor heating unit as defined herein; an oxygen reference pole generating unit as defined herein; a damage avoidance time elapse determining unit as defined herein; and a reference generation current application permitting unit as defined herein.

Abstract: An ammonia gas sensor including a reference electrode (320) is formed on the back surface of a solid electrolyte member (310), and a detection electrode (335) is formed on the front surface of the solid electrolyte member (310). A detection lead (350) is provided on the front surface of the solid electrolyte member (310) such that the detection lead (350) is connected to the detection electrode (335). An insulating layer (340), (380) is provided between the detection lead (350) and the solid electrolyte member (310), or on the detection lead (350).

Abstract: To provide a gas sensor element having a base body whose durability is unlikely to deteriorate during the use and exhibiting excellent endurance and responsiveness. [Means for Solution] A gas sensor element 2 comprising: a closed-bottomed cylindrical base body 28 made of solid electrolyte which contains zirconia as a principal component; an outer electrode 26 formed on an outer surface of the base body 28; an inner electrode 27 formed on an inner surface of the base body 28; and an adhesive layer 29 formed between the base body 28 and the outer electrode 26 and containing zirconia as a principal component, wherein a proportion of tetragonal in zirconia particles of the base body 28 falls within the range from 45% or more to 60% or less and, wherein a proportion of tetragonal in zirconia particles of the adhesive layer 29 is greater than that of tetragonal in zirconia particles of the base body 28.

Abstract: The present invention provides oxygen partial pressure control apparatuses that can control the partial pressure of oxygen in atmospheric gases in processing apparatuses or the like to within the range of 0.2 to 10?30 atm, while maintaining low material and operational cost conditions.

Abstract: A procedure to calculate the Lambda value with a wideband Lambda sensor of an internal combustion engine of a motor vehicle is thereby characterized, in that from the measured pumping electricity and the sensitivities of the wideband Lambda sensor as well as the gas concentration ratios, in the lean operation an oxygen concentration and in the rich operation an oxygen deficit are determined and from these respectively a conclusion is drawn about the Lambda value using the Pischinger Formula.

Abstract: A sensor element including: a first solid electrolyte layer as defined herein; and a second solid electrolyte layer as defined herein, wherein the first solid electrolyte layer includes a first inner insulating layer, a first outer insulating layer, a first inner conductive layer and a first outer conductive layer as defined herein, the second solid electrolyte layer includes a second inner insulating layer, a second outer insulating layer, a second inner conductive layer and a second outer conductive layer as defined herein, and the first outer conductive layer and the second outer conductive layer are in contact with one another.

Abstract: A plural-cell gas sensor including at least an oxygen pump cell (40) comprising a solid electrolyte ceramic layer; an internal space (210) formed between the cells; and a heater substrate (190) arranged on the side of the oxygen pump cell; the heater substrate heating the oxygen pump cell that pumps oxygen out of the internal space.

Abstract: A sensor element is provided for determining at least one physical property of a gas mixture in at least one gas chamber, which includes at least one component to be identified, especially oxygen, and at least one oxidizable component, especially a combustion gas. The sensor element has at least one first electrode, at least one second electrode, and at least one solid electrolyte connecting the at least one first electrode and the at least one second electrode. The at least one second electrode has a lower catalytic activity, particularly a lower electrocatalytic activity with respect to the at least one oxidizable component than the at least one first electrode.

Abstract: A single cell oxygen sensor apparatus and method are disclosed. An yttrium-based stabilized layer having electrical terminals connected to the yttrium-based stabilized layer can be provided on a substrate, wherein the yttrium-based stabilized layer is excitable by a constant current applied to the electrical terminals. A plurality of electrodes are located on a side of the yttrium-based stabilized layer and a plurality of heater elements located on said substrate opposite said yttrium-based stabilized layer. The heater elements can maintain the yttrium-based stabilized layer at a particular temperature. A cavity is formed and located between the yttrium-based stabilized layer and the heater elements. The partial pressure of oxygen can be measured by comparing the partial pressure of oxygen within the cavity with respect to the partial pressure of oxygen in the atmosphere external to the single cell oxygen sensor apparatus.

Abstract: A sensor element is provided for determining a physical property of a measuring gas, especially of the concentration of at least one gas component in the measuring gas, which has at least one ceramic layer, a diffusion barrier adjoining the at least one ceramic layer and at least one electrode that is exposed to the measuring gas diffusing through the diffusion barrier. In order to reduce the production variations with respect to the static pressure dependence and the limiting current of the diffusion barrier), the proportions of silicon in the diffusion barrier and in the at least one ceramic layer are approximately equal and differ by not more than 1 wt. %.

Abstract: A gas sensor element has a solid electrolyte body of oxygen ionic conductivity, a target gas electrode and a reference gas electrode formed on both surfaces of the solid electrolyte body, respectively, a porous diffusion resistance layer, and a catalyst support trap layer. The porous diffusion resistance layer covers the target gas electrode and through which target gases to be measured are passing. The catalyst support trap layer is formed on the outer surface of the porous diffusion resistance layer and supports noble metal catalyst. In the gas sensor element, the noble metal catalyst is made of platinum, rhodium, palladium supported in the catalyst support trap layer. In particular, an addition amount of palladium in the total amount of the noble metal catalyst is within a range of 2 to 65 wt %.

Abstract: Apparatus and methods for measuring NOx concentrations are disclosed. One method includes the steps of providing a gas stream having a NO concentration and a NO2 concentration, wherein a sum of the NO concentration and the NO2 concentration is a total NOx concentration; contacting the gas stream with a first zirconium oxide based oxygen sensor at a first temperature to achieve a first NO:NO2 equilibrium at the first temperature; contacting the gas stream with a second zirconium oxide based oxygen sensor at a second temperature to achieve a second NO:NO2 equilibrium at the second temperature; and determining the total NOx concentration by measuring a response of the first zirconium oxide based oxygen sensor to achieve the first NO:NO2 equilibrium and a response of the second zirconium oxide based oxygen sensor to achieve the second NO:NO2 equilibrium. The second temperature is different than the first temperature.

Abstract: A sensor element of a gas sensor, which is used for determining the concentration of ammonia and, optionally, at least one further component of a gas mixture, in particular in exhaust gases of combustion engines. The sensor element includes at least one first auxiliary electrode and at least one measuring electrode positioned downstream in the flow direction of the gas mixture, which are in direct contact with the gas mixture, a signal generated by the measuring electrode being used at least intermittently for determining the concentration of ammonia. A potential, at which ammonia contained in the gas mixture is oxidized, is applied at least intermittently to the first auxiliary electrode or the measuring electrode.

Abstract: A sensor element for the determination of the concentration of gas components in a gas mixture, particularly of the concentration of gas components in the exhaust of internal combustion engines, with two electrodes, that together with a solid electrolyte constitute a pumping cell, whose outer pumping electrode is exposed to the gas mixture by way of a porous protective layer, and with a reference electrode, which is disposed on the solid electrolyte and is exposed to a reference gas, and which with a solid electrolyte and a Nernst electrode constitutes a concentration or Nernst cell, is thereby characterized in that at least periodically the Nernst voltage between the outer pumping electrode and the Nernst electrode is tapped and analyzed.

Abstract: A gas concentration measuring apparatus for use in air-fuel ratio control of motor vehicle engines is provided which is designed to select or determine a correction factor for an output of an A/F sensor, as produced through a sensor control circuit, for compensating for errors in circuit characteristics of the A/F sensor and/or the sensor control circuit to ensure the accuracy of measurement in the apparatus.

Abstract: A device is provided for measuring the gas content in a molten metal, the device including an immersion end having a gas-collecting body, a gas supply line opening on the immersion end, and a gas discharge line for the gases passing through the gas-collecting body. The gas-collecting body contains materials, which in contact with the molten metal do not form liquid reaction products.

Abstract: A gas sensor includes a first space for a measurement gas from a gas-introducing hole via a first diffusion rate-determining section, a main pumping means for controlling a partial pressure of oxygen in the measurement gas introduced into the first space to have a predetermined value, a second space for the measurement gas from the first space via a second diffusion rate-determining section, and a measuring pumping means for reducing or decomposing a NOx component in the measurement gas introduced from the second space via a third diffusion rate-determining section so that oxygen produced thereby is pumped out to detect a current generated by pumping out the oxygen. A ratio (Wc/We) between a width (We) of an end of a sensor element and a width (Wc) of the gas-introducing hole is not less than 0.3 and less than 0.7.

Abstract: The present invention relates to a multi-functional sensor system that simultaneously measures cathode and anode electrode potentials, dissolved ion (i.e. oxide) concentration, and temperatures in an electrochemical cell. One embodiment of the invented system generally comprises: a reference(saturated) electrode, a reference(sensing) electrode, and a data acquisition system. Thermocouples are built into the two reference electrodes to provide important temperature information.

Abstract: A micro fuel cell sensor having laminated gas permeable membrane. The sensor comprises a housing, first and second gas diffusing electrodes spaced from one another, a fuel-cell spacer having an acidic electrolyte disposed between said first and second electrodes, and two gas permeable membranes. The first gas permeable membrane comprises a polymer laminated on a metal substrate, wherein the substrate comprises pores that have dimensions at least less than one-half the thickness of the polymer film.

Abstract: A gas sensor is constructed as follows. A protector (4) covering around a gas sensing element (2) has an inner hollow-cylindrical portion (6) and an outer hollow-cylindrical portion (7) that is provided coaxially with the inner hollow-cylindrical portion (6) with an air space (8) in between. Outer-wall gas inlet openings (13) are formed in the outer hollow-cylindrical portion (7), and guiding bodies (10) extending inward are attached to the outer-wall gas inlet openings (13). Inner-wall gas inlet openings (11) are formed in the inner hollow-cylindrical portion (6) at positions nearer to the gas sensing element (2) than the outer-wall gas inlet openings (13). A side wall (9) face of the inner hollow-cylindrical portion (6) opposite the outer-wall gas inlet openings (13) is formed so as to be parallel to a side wall (12) of the outer-hollow cylindrical portion (7) or so as to have a slop-like shape with a diameter enlarging in the axial direction toward a bottom wall (17) of the protector (4).

Abstract: An oxygen sensor 10 includes an oxygen detection element 20, which assumes a hollow tubular shape extending along the axis. The oxygen detection element 20 has a closed tip end and an opened rear end. An internal electrode layer 23 is formed on an inner circumferential surface 22 of the oxygen detection element 20. The sensor 10 also has a terminal member 30 which is in contact with the internal electrode layer 23 and in electrical connection therewith. The terminal member 30 has press contact portions 34c and 34d which come into press contact with the inner circumferential surface 22 of the oxygen detection element 20 to hold the terminal member 30 in the oxygen detection element 20, and conduction portions 35b which come into press contact with the internal electrode layer 23 on the inner circumferential surface 22 of the oxygen detection element 20 and into electrical connection with the internal electrode layer 23.

Abstract: Disclosed is metal composite oxides having the new crystal structure. Also disclosed are ionic conductors including the metal composite oxides and electrochemical devices comprising the ionic conductors. The metal composite oxides have an ion channel formed for easy movement of ions due to crystallographic specificity resulting from the ordering of metal ion sites and metal ion defects within the unit cell. Therefore, the metal composite oxides according to the present invention are useful in an electrochemical device requiring an ionic conductor or ionic conductivity.

Abstract: In at least one embodiment, a method is described for measuring concentrations of gas moieties in a gas mixture. A mixed-potential gas sensor is exposed to a gas mixture in order to obtain a first and a second mixed-potential gas sensor output responses. The first output response and a second output response are deconvoluted to measure a first analyte gas concentration and a second analyte gas concentration. Some of the output responses may be used as inputs to a control system.

Abstract: A catalytically active layer that is used, for example, as an electrode for a solid electrolyte-based sensor element of a gas sensor for determining a gas component in a gas mixture. The catalytically active layer includes a metallic component, that includes a noble metal in the form of platinum, rhodium, and/or palladium, and additionally a base metal. At least a portion of the originally present base metal is replaced by cavities in the metallic component.

Abstract: The present invention relates to an electrochemical sensor for determining the concentration of a group IA metal in a fluid such as molten metal. The sensor comprises a substantially pure quantity of the group 1A metal as a reference electrode (13) contained in a sensor housing (3), and a solid electrolyte constituting at least part of the sensor housing (3). The electrolyte is in electrical contact with the reference electrode (13) and the sensor is capable of operating at temperatures in excess of 973K. In a preferred arrangement, the sensor comprises a two part elongate conductor (15), a first part (17) of which extends from the reference electrode (13) into a refractory seal (11a), and a second part (19) of which extends from within the refractory seal (11a) externally of the sensor, the two parts (17, 19) being welded together.

Abstract: The invention includes a method and apparatus for a chromatography system having a chromatographic column for separating gases in a mixture from one another and an electrochemical gas sensor coupled to the chromatographic column for detecting a gas being emitted from the column. The electrochemical gas sensor further includes a substrate having a surface for depositing electrodes thereon, an ionomer membrane in contact with the surface, an electrode in contact with the surface, and an opening in the ionomer membrane in a location proximate to the electrode for permitting a gas to diffuse through the opening to simultaneously contact the electrode and the ionomer membrane within the opening.

Abstract: A hydrogen sensor which may be employed in an overcharge/overdischarge detector for a battery and a hydrogen leakage detector for a fuel cell is provided. The hydrogen sensor includes a sensor element and a diffused resistor member. The gas to be measured passes through the diffused resistor member and reaches the sensor element. The sensor element outputs a signal indicative of the concentration of hydrogen contained in the gas as a function of a decrease in concentration of oxygen contained in the gas arising from reaction of the hydrogen on the oxygen. The diffused resistor member is so designed that speeds of diffusion of the hydrogen and the oxygen when passing through the diffused resistor member are different from each other for increasing the sensitivity of measurement of the concentration of hydrogen.

Abstract: The invention includes a method and apparatus for a chromatography system having a chromatographic column for separating gases in a mixture from one another and an electrochemical gas sensor coupled to the chromatographic column for detecting a gas being emitted from the column. The electrochemical gas sensor further includes a substrate having a surface for depositing electrodes thereon, an ionomer membrane in contact with the surface, an electrode in contact with the surface, and an opening in the ionomer membrane in a location proximate to the electrode for permitting a gas to diffuse through the opening to simultaneously contact the electrode and the ionomer membrane within the opening.

Abstract: The invention relates to a method and apparatus for providing an electrochemical gas sensor having improved response time for detecting a gas introduced into the sensor. The sensor includes a substrate having a first surface and a second surface and an electrode deposited on the first surface. The sensor also includes an ionomer membrane in contact with the first surface and the electrode. The ionomer membrane has an opening in a location proximate to the electrode for permitting gas introduced into the sensor to diffuse through the opening to simultaneously contact the electrode and the ionomer membrane within the opening. The substrate further includes at least one hole extending from the first surface to the second surface for permitting moisture to diffuse through the at least one hole to contact the ionomer membrane for enhancing sensitivity.

Abstract: A low cost room temperature electrochemical gas sensor with humidity compensation for sensing CO, alcohol vapors and other toxic analyte gases has a solid protonic conductive membrane with a low bulk ionic resistance. A sensing electrode and a counter electrode, optionally a counter electrode and a reference electrode, which are separated by the membrane, can be made of mixed protonic-electronic conductors, or can be made of a thin electrically conducting film such as platinum. A reservoir of water maintain the solid protonic conductive membrane at constant 100 percent relative humidity to compensate for ambient humidity changes. Embodiments of the inventive sensor also include an electrochemical analyte gas pump to transport the analyte gas away from the counter electrode side of the sensor.