Abstract: An NOx sensor having an electrochemical cell having a solid electrolyte body and a first and a second electrode, a portion that permits restricted communication of the first electrode with an external measurement gas space, a catalyst disposed adjacent the first electrode for decomposing NOx, a device for applying a current between the first and second electrodes, a current measuring device for detecting a current flowing between the first and second electrodes, an oxygen partial pressure measuring device for detecting an oxygen partial pressure of the atmosphere surrounding the first electrode, and a control device for calculating the concentration of NOx contained in the measurement gas in the external space, based on a first and a second current value.

Abstract: Disclosed is an enzyme sensor for measuring a predetermined substrate concentration by potentiometric or amperometric response on the basis of an enzyme. In one aspect, a solid-state enzyme sensor measures a predetermined substrate concentration by potentiometric response and includes a solid enzyme membrane-coated electrically conductive base, redox layer or ion-sensitive layer. In another aspect, a solid-state enzyme sensor measures a predetermined substrate concentration by amperometric response and includes a solid enzyme membrane-coated oxygen reduction catalyst layer. Also disclosed is an enzyme control layer for controlling the outflow and inflow of the enzyme layer.

Abstract: Methods and apparatus for detecting immunochemical reactions and levels of antigens and antibodies in serum. A selected immunochemical reactant is bound to the surface of a first electrode. A second electrode is provided such that the electrodes generate a galvanic current when electrically interconnected and immersed in conductive aqueous solution. The electrodes are electrically interconnected and immersed into a conductive aqueous solution containing the complementary immunochemical reactant to the bound immunochemical reactant. The galvanic current generated by the immersed electrodes is measured as a function of time. The level of the complementary immunochemical reactant in the solution is calculated by comparing the measured current with a standard current.

Abstract: An enzyme electrode unit having, on the surfaces of the base electrodes thereof, an enzyme-immobilized membrane for oxidizing or reducing a target substance to be measured, and a diffusion-limiting membrane unit of a two-layer structure disposed on the surface of the enzyme-immobilized membrane, only the diffusion-limiting membrane having a lower target substance diffusion limiting effect being replaceable, thus maintaining substantially constant the general target substance diffusion limiting effect of the diffusion-limiting membrane unit, even after the replaceable diffusion-limiting membrane has been replaced.

Abstract: Heteroaromatic compounds having at least two nitrogen atoms may be used to regulate consistency of alloy content and of deposit thickness. Modified nonionic surfactants which lack terminal hydroxy groups are used as grain refiners having low tendency to cause foam build-up in electroplating baths. Dioxolanes may be used to produce deposits having, as desired, a white uniform matte, a semi-bright plate, or a mirror bright surface.

Abstract: The aqueous alkaline bath for electrochemical deposition of a zinc-iron alloy according to our invention contains a zincate and a compound of iron with a sugar. Advantageously sugar including monosaccharides, trisaccharides and disaccharides such as sucrose are used to form this iron compound. The iron compound may be an iron saccharate. An alloy with superior corrosion resistance is the product of an electrochemical deposition using this bath.

Abstract: An ion sensor includes an ion sensitive membrane formed from a vinyl polymer based compound containing a hydroxyl and/or carboxyl group. The membrane is provided on an extended gate electrode on a gate electrode of a field-effect type transistor. The ion sensor also includes a reference electrode arranged in opposition to the extended gate electrode. The extended gate electrode and reference electrode are formed on a substrate different from the substrate on which the field-effect type transistor is formed. A divided part for an ion sensor is also provided and includes the portions of the ion sensor discussed above except for the reference electrode. The divided part is used with a separate reference electrode.

Abstract: Process for the visual inspection of an electrode (anode) having an activated layer for electrogalvanizing plants for steel bands in which the electrode to be tested is inserted between anode and cathode of a sodium sulfate electrolytic cell with the surface to be tested facing toward the cathode. After a voltage is applied the development of the gas bubbles on the activated layer is monitored by means of a video camera.

Abstract: A method for fabricating exactly aligned apertures for use in electron and ion microscopy involves the placing of a very sharply pointed tip (1) in front of a set of extremely thin, precisely spaced metal foils (3,5) in an atmosphere of heavy gas atoms. The application of an elevated voltage at the tip (1) will result in a sputtering operation to commence and erode the metal foils (3,5) at a location underneath the facing tip (1). The sputtering operation is continued until the first ions are detected to emerge on the far side of the lens structure (2).

Abstract: A sensor of the enzyme-electrode type comprising an electrode and a membrane permeable to liquids and solutes which is positioned between the electrode and a specimen containing the analyte to be determined, is characterized by the fact that a layer of a porous material, positioned in the membrane between the enzyme-containing layer and the specimen, has been treated to at least partially fill the pores with a liquid of limited volatility which is not significantly soluble in water and is to some degree a solvent for the analyte.

Abstract: A flow through polarographic or other voltammetric analyzer utilizes an improved deoxygenator/pulse dampener in the form of a knitted or other form of convoluted oxygen permeable tubing, such as silicone rubber tubing, through which the flow sample passes. The oxygen permeable tubing is mounted in a chamber containing a flowing inert gas under a positive pressure.

Abstract: A process and an apparatus for manufacturing electrocatalytic electrodes. The process comprises the steps of immersing a substrate in a plating bath containing metal ions and electrocatalytic material in particles form, such as Ni, NiAl, and CoAl, among others. Electric current is established in the bath inducing a deposition of metal on the substrate by reduction of metal ions and, simultaneously, the cell containing the plating bath is inverted periodically to cause a recurrent migration of the particles of electrocatalytic material, under the effect of gravity, toward the substrate, in order to build-up a layer of electrocatalytic material on the substrate, the particles of the electrocatalytic material being fixed on the substrate by the reduction of metal ions.

Abstract: There is provided a novel method of testing for the presence of an analyte in a fluid suspected of containing the same. In this method, in the presence of the analyte, a substance capable of modifying certain characteristics of the substrate is bound to the substrate and the change in these qualities is measured.While the method may be modified for carrying out quantitative differential analyses, it eliminates the need for washing analyte from the substrate which is characteristic of prior art methods.

Abstract: An oxygen concentration detecting device includes at least one oxygen concentration detecting element formed by an oxygen-pumping element and a cell element, composed of an oxygen ion-conductive wall, separating a pair of electrodes. The oxygen-pumping element and cell element define a gas diffusion chamber. A current detecting resistance forms a series circuit with the oxygen-pumping element. A voltage applying circuit applies to the series circuit an output voltage corresponding to the difference between a voltage between the electrodes of the cell element and a first reference voltage. An output detecting circuit outputs a voltage signal corresponding to a value of pumping current flowing through the resistance. An operational amplifier has a non-inverting input terminal supplied with a second reference voltage, an inverting input terminal connected to one end of the resistance, and an output terminal connected to the other end of the resistance.

Abstract: Processes are described for electroplating metal or alloy on superconducting oxides using either a nonaqueous bath or aqueous bath with suitably applied potential. Articles made in accordance with the electroplating process are also described.

Abstract: At the surface of an insulating substrate there are provided a working electrode and an counter electrode with a set space from the working electrode and a gas-permeable, proton-conductive film with which the surfaces of the electrodes are overlaid in such a manner as to form an integrated whole with the electrodes. By applying a set voltage between the two electrodes, flammable gas which has permeated the gas-permeable, proton conductive film is made to undergo oxidation and reduction at a surface of the working electrode, and protons which have been produced thereby move toward the counter electrode in the gas-permeable, proton-conductive film, so that the concentration of the flammable gas can be measured. A reference electrode can be provided for the purpose of stabilizing potential of the working electrode. A mechanism which is described above can be applied to a gas sensor of field-effect transistor type.

Abstract: A gold plating bath having potassium aurous cyanide and thiourea complexing agent dissolved in water and adjusted to an acidity of pH 3 or lower can be used as either electroplating or electroless plating bath. Bright gold electroplating is possible when a brightener is added to the bath. Electroless plating is possible when a reducing agent, typically sodium hypophosphite is added to the bath.

Abstract: A process for electroplating palladium containing deposits from baths comprising a combination of a surfactant and a brightener combination. The surfactant is an alkyl, ammonium-type salt containing 4 to 35 carbon atoms. The brightener is 0-benzaldehydesulfonic acid, 1-naphthalene sulfonic acid, 2-naphthalenesulfonic acid, benzenesulfinic acid, oxy-4,4-bis (benzene) sulfinic acid, p-toluene sulfinic acid, 3-trifluoromethyl benzene sulfinic acid, allyl phenyl sulfone, 0-benzoic sulfamide, benzylsulfonyl propionamide, phenylsulfonyl acetamide, 3-(phenylsulfonyl) propionamide, benzene sulfonamide, bis (phenylsulfonyl) methane, guanidine carbonate, sulfaguanidine or nicotinic acid. This combination provides deposits having superior adhesion and ductility.

Abstract: An apparatus for measuring hydrogen cyanide vapor content in the air having an electrode cell with an electrolyte which accommodates an indicator electrode with a sensor member, which is connected by means of a salt bridge with a comparison electrode immersed in the electrolyte, an amplifier, and a recorder, the electrode cell being divided by means of an ion exchange membrane into two compartments, the first compartment containing an electrolyte which is free from cyanide ions and accommodating the comparison electrode, the indicator electrode being positioned above the electrolyte level in the second compartment which also accommodates a means for supplying the electrolyte from the second compartment to the sensor member of the indicator electrode, said means ensuring supply of the electrolyte at regular intervals and being coupled to a compressor.

Abstract: The invention is directed to a measuring cell for detecting a component of a measuring sample. The measuring cell includes a housing in which an electrolyte as well as a measuring electrode and a counter electrode are accommodated. A membrane separates the electrolyte from the measuring sample and is pressed by a supporting part against the measuring surface of the measuring electrode. This membrane is improved such that it can compensate for volumetric changes in the electrolyte chamber in the clamped condition. The measuring cell is further improved in that a small amount of readiness energy is required for the operational-ready condition and the attachment of the membrane is not critical for its later function. A first portion of this membrane is pressed against the measuring electrode. In the region outside of this first portion and extending up to the peripheral edge where it is attached, a compensating membrane portion is formed which can change in its configuration.