Abstract: A reservoir of electrolyte is placed in communication with the electrolyte of an electrochemical or electrolytic cell which is adapted for oxygen analysis. A cathode is placed in the electrochemical cell and an anode is placed in the reservoir, with a potential of 1.5 VDC applied between them. At the cathode a mild electrolysis of water occurs and a film of highly reactive hydrogen is generated. Similarly, oxygen is generated at the anode. The equilibrium partial pressure of the dissolved oxygen in the electrolyte of the electrochemical or electrolytic cell is reduced via its consumption in the reaction with the hydrogen to form water. Oxygen generated in the reservoir is allowed to effervesce. Thus, an electrolyte devoid of dissolved oxygen can be maintained which allows an accurate analysis of the gaseous sample stream.
Abstract: This invention is directed to a method of copper-nickel-chromium bright electroplating which provides excellent corrosion resistance, characterized in that said bright electroplating film comprises copper and nickel plating levers formed on a basis material or a nickel plating layer directly formed on a basis material, a microporous layer of a thickness of 0.2-2 .mu.m codeposited on said nickel plating layer by adding calcium salt and titanium oxide to Watts bath type of nickel plating bath, chromium plating layer with a thickness of 0.01-0.25 .mu.m on said microporous layer and a chromium plating surface with micropores of 20000-500000/cm.sup.2, and is directed to the plating films obtained by the method.
Abstract: A device for performing rapid determinations on a real-time basis of about three to five seconds of the concentration of HCl in the atmosphere includes an air inlet conduit for sampling the HCl laden air, a pump for introducing trapping solution into the air inlet conduit, a spiral impinger for mixing and combining the air and trapping solution, a separator for separating a portion of the trapping solution and entrained air from the remaining trapping solution, and electrode flow cell for receiving the remaining trapping solution and for determining the chloride ion concentration in the trapping solution. The electrode flow cell includes a measuring electrode having a silver wire having a silver chloride coating inserted in the flow path of the trapping solution. A selector valve is inserted between the separator and the flow cell for alternatively feeding either the separated trapping solution to the flow cell or a standardizing solution to the flow cell.
March 16, 1989
Date of Patent:
October 2, 1990
The United States of America as represented by the Secretary of the Army
Abstract: The ultramicroelectrode comprises a wire or filament of noble metal and/or carbon on which an insulating layer is provided. The insulating layer is made from a cross-linked alkenyl-substituted poly(1,4-phenylene) ether, poly(1,4-phenylene) thioether or poly(1,4-aniline). This ultramicroelectrode can be used as a disk, cylindrical, bipolar or shielded electrode and may be used as a stimulating electrode, amperometric or potentiometric microsensor or as an electrode for analytical measurement, e.g. for inverse voltammetry.
Abstract: An oxygen sensor includes an electrically conductive substrate directly coated with an electrolytic oxidative polymeric membrane, which contains a porphyrin compound and a metal complex thereof. Also provided is an oxygen sensor capable of being subjected to a temperature calibration and including an oxygen electrode consisting of an electrically conductive substrate directly coated with a porphyrin derivative compound and a metal complex compound thereof, a reference electrode, a gelled polymeric electrolyte in which the oxygen electrode and reference electrode are immersed, and an oxygen-selective permeable membrane coating the gelled polymeric electrolyte. The electrically conductive substrate according to the present invention is formed from a material inactive with oxygen gas, such as indium tin oxide, iridium oxide, nickel or gold.
Abstract: A zinc- or zinc alloy-coated steel sheet having an excellent spot-weldability, comprising: a base steel sheet; one or more layers coated on the steel sheet, at least one of the coated layers containing zinc as a major component; and an oxidized layer formed on the outermost of the coated layers and containing zinc in an amount of from 0.03 to 3.0 g/m.sup.2, the oxidized layer containing at least one of zinc oxide and zinc hydroxide.
Abstract: Quantitative determination of ozone contained in a fluid by an amperometric method comprises the steps of:(A) providing an amperometric cell having a sensing electrode, a counter electrode, an aqueous electrolyte in contact with the sensing electrode and the counter electrode, and a membrane that is substantially impermeable to the electrolyte but permeable to gaseous media including ozone and oxygen for containing the electrolyte within the cell and for separating it from the fluid maintained external to the cell;(B) providing in the aqueous electrolyte a redox catalyst for chemically transforming the ozone upon its permeation through the membrane into an intermediary electroactive species capable of generating upon reaction with the sensing electrode an indicative electrical signal in proportion with a concentration of the ozone in the fluid;(C) applying a predetermined potential across the sensing electropde and the counter electrode;(D) measuring a cell current generated by reaction of the intermediary el
Abstract: Measuring instruments for coulometrically measuring the thickness of metallic coatings pump the electrolyte from the first chamber 11 into the second chamber 12 and vice versa during the measurement. As a result, fresh electrolyte constantly reaches the measuring spot below the outlet orifice 7 and the troublesome formation of gas bubbles at this measuring spot is completely or substantially reduced. If the probe 3 is, however, inadvertently lifted off the coating 2, the pumped electrolyte spurts at high speed out of the outlet orifice 7. As a result, personnel and also material may suffer damage. The disposal presents difficulties. As a solution, provision is made for the entire system to employ underpressure and the maximum pressure occurring in chamber 11 or 12 is less than the external pressure. If the probe 3 is now inadvertently lifted during the measurement process, the electrolyte is sucked back into the first chamber 11 and/or the second chamber 12 and nothing is contaminated.
Abstract: An additive plating bath and process are described for use in printed circuit manufacturing for applying copper to thick film patterns, said bath includes a low concentration of sulfuric acid, copper sulfate, urea, glycerin and a surface active agent in an aqueous solution.
October 25, 1989
Date of Patent:
September 4, 1990
International Business Machines Corporation
Abstract: Electrolytic galvanizing process in which steel strip to be zinc coated is passed continuously through an acid electrolyte solution containing zinc ions and is used as a cathode, while the electrolyte solution is made to flow in the space between the cathode and the anode, in a cell having flat parallel electrodes. The plating current density and the fluid dynamic conditions of the electrolyte are related by the equationI=K C Re.sup.nin which I is 15-300 A/dm.sup.2, K is 0.01-0.0001 A/dm.sup.2 l/g, C is 40-80 grams of zinc per liter of electrolyte solution, Re is the Reynolds number between 1,000 and 200,000, and n is 0.55-0.85. Preferred values are K=0.001, C=80 g/l and n is 0.7.
Abstract: A method of gas reaction process control in which plasma gas generated in a location different than a location at which a specimen is held is transported to a location at which the specimen is held and gas processing of the specimen is carried out. A control electrode with porous structure permeable to the plasma gas is provided in the transportation route and a voltage is applied to the control electrode voltage for adjusting the specimen surface potential so as to prevent degradation of the specimen due to specimen surface potential.
February 28, 1989
Date of Patent:
August 21, 1990
Agency of Industrial Science & Technology, Ministry of International Trade & Industry
Abstract: A two electrode assembly in a polarographic cell includes a sensor electrode and a silver/silver chloride reference electrode in which silver metal is in contact with a substantial reservoir of silver chloride.
October 2, 1989
Date of Patent:
August 21, 1990
Nova Biomedical Corporation
Chung C. Young, James E. Fowler, Alan R. Silverman
Abstract: A limiting current-type oxygen sensor including (a) a pair of oxygen ion-permeable substrates made of a zirconia solid electrolyte; (b) at least one diffusion pore provided in at least one of the substrates, which extends substantially along the thickness of the substrate for causing oxygen diffusion through the diffusion pore to be a rate-determining step; (c) a sealing member for fixing the pair of substrates such that a closed chamber is defined between the substrates; and (d) a pair of porous electrodes provided on both outer and inner surfaces of each electrode.
Abstract: An oxygen sensor having construction of an upper open end portion plugged with a grommet through which lead wires are taken out of a protecting metallic cover. A resin grommet of a heat resistant resin such as Teflon, polyimide or the like is fitted in the upper open end portion of the metallic cover with a portion of the grommet being extended from upper open end portion of the metallic cover. A heat resistant non-metallic tube such as Teflon, polyimide, silicone rubber, fluororubber tube is closely fitted on the periphery of the extended portion of the resin grommet and the periphery of the upper end portion of the metallic cover and a metallic tube being closely fitted on the periphery of a portion of the non-metallic tube which is fitted on at least the metallic cover.
Abstract: An electrochemical gas sensor having a flexible membrane mounted at the sensing end of a housing, to dissipate increased electrolyte pressure, a small sensing electrode cooperating with a relatively thick porous sheet of polytetrafluoroethylene (PTFE) supported by the flexible membrane, and the housing also containing an electrolyte and a counter electrode, with suitable circuitry connected to the electrodes for quantifying the current generated by the sensor.
Abstract: A method for improving the adhesion between metal and metal oxide films and an improved multiple layer coated article comprising primer layers between metal and metal oxide films are disclosed. Copper containing layers are used as primer layers; for example, copper oxide. The several layers are prepared by sputtering.
Abstract: A method of preparing a compound useful as a brightener in aqueous copper electroplating solutions comprising reacting a compound of the following formula: ##STR1## with a compound of the formula:HS--R.sub.2 --Z.sub.nwherein:R.sub.1 and R.sub.2 are each an alkylene containing from 2 to 8 carbon atoms, an arylene, an alkylarylene, an arylalkylene or a heterocyclic group containing at least one nitrogen atom in its ring structure:x, y and z each is a hydrogen or a water-solubilizing group; andn is an integer of from 1 to 4; with the proviso that:when R.sub.1 is a heterocyclic group, x, y and z are hydrogen and R.sub.2 is an alkylene containing from 2 to 8 carbon atoms, an arylene, an alkylarylene or an arylalkylene;when R.sub.2 is a heterocyclic group, x, y and z are hydrogen and R.sub.1 is an alkylene containing from 2 to 8 carbon atoms, an arylene, an alkylarylene or an arylalkylene;when x or y is a water-solubilizing group, R.sub.
Abstract: An oxygen sensor having an oxygen sensing element which includes a solid electrolyte body made of an oxygen-ion conductive solid electrolyte material, and a measuring electrode and a reference electrode formed on the solid electrolyte body, the measuring and reference electrodes, respectively, communicating with a measurement gas, and a reference gas having a predetermined oxygen concentration, so that an electromotive force is induced between the measuring and reference electrodes, based on a difference in oxygen concentration between the measurement gas and the reference gas. The measuring electrode includes a conductor principally consisting of platinum, and lead and/or zinc serving as an activation component for the platinum. An amount of the lead and/or zinc per 1 mg of the platinum is within a range of 0.2-100 .mu.g.
Abstract: A plurality of frequency selective limiting (FSL) units are concurrently prepared on a common substrate by depositing a first ferrite member onto a metallized surface of the substrate. The first ferrite member is formed by sputtering a first ferrite film onto the metallized surface and subsequently growing a ferrite layer thereon. A plurality of signal carrying conductors are positioned in spaced relation on the first ferrite member. A second ferrite member is deposited on top in the same manner as the first ferrite member. The overall structure is diced into individual units that are then metallized thereby providing a plurality of FLS's.
Abstract: An electrochemical device for detecting a measurement fluid, which includes a planar solid electrolyte body, a first electrode formed on the planar solid electrolyte body and substantially exposed to the measurement fluid, a second electrode formed on the planar solid electrolyte body and substantially isolated from the measurement fluid, a porous layer disposed in direct contact with the second electrode, and a device for applying an electric current so as to flow from the second electrode to the first electrode. The device may further include a third electrode, and a fourth electrode substantially directly exposed to the measurement fluid. In this case, the first and third electrodes are exposed to the measurement fluid through a thin flat space or porous layer having a predetermined diffusion resistance to the measurement fluid, and a current regulating device is connected between the third and fourth electrodes, for controlling an atmosphere adjacent to the first electrode.