Abstract: A metallic indicator electrode senses the anionic charge per unit time borne by the dispersed phase of a stream of an aqueous dispersion of negatively charged particles by virtue of the potential developed by the electrode as measured by a voltmeter. The developed potential can be used downstream, for example, to control the addition of a water treatment chemical or extraction of water from the stream.

Abstract: Generation and stabilization of glow plasma by discharge under atmospheric pressure are monitored by detection of the number of electric current pulses per one-half cycle of an alternating voltage applied to a discharge device. Alternately, or in addition, a Lissajous figure is generated showing a correlation between the applied alternating voltage and a current flow in the discharge device, and a discharge state is discriminated according to the Lissajous figure. Accurate, quick and simple monitoring of atmospheric pressure glow discharge plasma and the control thereof are thus made possible.

Abstract: A microphotolysis and microphotoanalysis process applying precise quantities of focused light energy to a precise microscopic area of a very small cell sample to activate a chemical agent which permits measurement of cell fragility.

Abstract: A digital sensor network scanner for use in monitoring resin flow and its re progress during a resin fabrication process in which a plurality of non-intersecting electrically conductive threads are arranged in a grid-like configuration with each sensor thread having a sensor input for a sensor data path so as to create a plurality of sensors is disclosed in which a first section of the scanner supplies time encoded pulses to the sensor input path. A second section of the sensor network scanner includes a plurality of detectors which are connected to the sensor data path as well as to a plurality of LEDs and which are also triggered by the same time encoded pulses applied to the sensor input path. When a sensor data path is in a conducting state, the applied time encoded pulses propagate down the sensor data path to the detector which, having simultaneously received a signal from both the network scanner and the sensor, illuminates the LED.

Abstract: This method and apparatus detects the potential for corrosion of pipes fabricated out of conductive material embedded in non-conductive material, due to contact between a conductive medium foreign to the pipe and the conductive material embedded within the pipe wall. The electric potential between the foreign medium and the pipe conductive material is determined. The stability of the potential is then ascertained. If the potential does not vary beyond a predetermined range over a period of time, the potential is deemed stable and is indicative of contact between the foreign medium and the conductive material within the pipe, fostering corrosion. An unstable voltage indicates lack of electrical contact.

Abstract: A method and apparatus for determining the quality of a colloidal suspension. According to the method of the present invention, an oscillating input electrical signal is applied simultaneously to a sample of the colloidal suspension to be tested and to a reference resistor. The reference resistor has a predetermined impedance value that is substantially identical to the colloidal suspension. The input signal causes charge particles and molecules within both substances to move, thereby, giving rise to electrical currents. Thus, a test current is extracted from the colloidal suspension and a reference current is extracted from the reference resistor. Thereafter, a differential output current is derived by subtracting the reference current from the test current. The average value of the differential output current and the peak value of the test current are measured. Based on the peak value of the test current and the average value of the differential output, the quality of the colloidal suspension is determined.

Abstract: A method and an apparatus to electronically identify a page. Each page has a surface conductive trace that is coupled to an electronic circuit to measure the conductivity of the trace. The primary purpose of the conductive trace is to provide an identification for the page.

Abstract: A sensitive and rapid electrochemical sensor monitors motor oil deterioration, particularly antioxidation property, by determining the antioxidant and antiwear agent level remaining in an oil formulation. The electrochemical sensor is a two- or three-electrode electrochemical cell having a conductive electrolyte liquid or gel-like interphase over the electrode surfaces. The degree of deterioration of a motor oil in service is monitored by measurements of antioxidation or antiwear capacity of the oil. The electrochemical sensor can be used for monitoring other lubricants and hydrocarbons which contain electroactive additives. The electrochemical sensor allows measurements to be performed in-situ, without any chemical or physical pretreatment of the oil.

Abstract: An inactive state termination tester for determining the number of terminators connected to a bus when the bus is inactive. The termination tester monitors the bus for determining when it is inactive. During the periods of bus inactivity, the termination tester senses the bus to determine the number of terminators connected to the bus. The termination tester then displays how many terminators were detected and/or generates a signal to either enable or disable, respectively, a controllable bus terminator depending on if there are not enough or too many terminators determined to be connected to the bus.

Abstract: A method and apparatus for simultaneously measuring the streaming potential of a fiber suspension and a filtrate thereof. A container is provided having an inlet and an outlet for the flow of fiber suspension therethrough, and a filter screen divides the container into an upstream compartment and a downstream compartment. Each compartment has an electrode pair disposed therein, each electrode pair including a cylindrical outer electrode configured for flow of fiber suspension therethrough and an inner electrode. Each electrode pair is connected to a differential amplifier, with the differential amplifiers connected to a microprocessor.

Abstract: An apparatus for automated polyelectrolyte measurement in process materials comprises a sample vessel with an outer wall defining a cylindrical cavity and with a reservoir of larger diameter above and in communication with the cavity. A liner for the cavity and the reservoir are made of an electrically insulating material such as polytetrafluoroethylene. To clean the apparatus there is also provided an ultrasonic oscillator which is mechanically coupled to the sample vessel. In order to improve the cleaning process, the liner and preferably also the reservoir are attached to the outer wall in such a way as to resist tensile and shear forces and the ultrasonic oscillator is attached to the outer wall. Preferably, the liner is attached to the outer wall by an adhesive.

Abstract: A cell for measuring electrokinetic potential, such as a streaming potential, includes a housing having an interior chamber divided into an upper compartment and a lower compartment by a filter mesh on which is formed a pad of a fibrous dispersion to be measured. The cell is of particular utility in the manufacture of paper and is used in the manner described in U.S. Pat. No. 4,535,285. To assist flushing of the fiber pad from the filter mesh a nozzle assembly in the upper compartment is used to direct a jet of water at the filter mesh. An additional step to flush out fibrous material reaching the upper compartment is described. This uses an additional port.

Abstract: A device is disclosed for measuring the coagulation time of a blood sample placed in contact with an appropriate reagent is described. A vibratory field inside an insulating receptacle is generated. Voltage variations between two electrodes disposed in the receptacle are measured which are indicative of a change in viscosity of the sample.

Abstract: A method for measuring the thickness of very thin oxide layers on a silicon substrate. A corona discharge source repetitively deposits a calibrated fixed charge density on the surface of the oxide. The resultant change in oxide surface potential for each charge deposition is measured. By choosing a starting value for an assumed oxide thickness, the approximate change in silicon bandbending per corona discharge step is determined. The cumulative changes in bandbending versus oxide surface potential yields an experimental bandbending versus bias characteristic. A theoretical bandbending versus bias characteristic is established. The experimental and theoretical characteristics are matched at predetermined points thereof and then the assumed oxide thickness is iterated until both characteristics superimpose in the silicon accumulation region. The iterated oxide thickness that allows both characteristics to superimpose is the oxide thickness value being sought.

Abstract: An device for monitoring workplace air comprises a monitor cell comprising a base and a removable assembly. The removable assembly comprises (1) a flat, electrically insulating substrate having a first surface, (2) an electrolyte cell having an anode and a cathode disposed on the first surface, the anode and cathode spaced apart to define a controlled volume for holding a quantity of an electrolyte, and (3) means for applying a controlled electrical potential to the cathode. The base comprises (1) an air inlet portion for sampling air, (2) an air outlet portion connected to an air sampling pump, (3) a channel connecting the air inlet and the air outlet and adapted to introduce air to the electrolyte in the electrolyte cell, (4) a reservoir for storing the electrolyte for the electrolyte cell, and (5) a wick for supplying electrolyte from the reservoir to the electrolyte cell.

Abstract: A new method and apparatus is described for conducting an integrity test on porous membranes and membrane filters and for conducting a pore-size characterization of membrane. The method and apparatus apply to membrane integrity tests and pore-size characterizations which are based on the dependence on the pore size of the pressure required to intrude a non-wetting, electrically conductive liquid into and through the pores. Electrical-measurement methods are described for identifying the pressure at which intrusion occurs.

Abstract: A cathodic protection measurement apparatus including a coupon made of similar material as a buried metal pipeline to form an artificial holiday, where the coupon is buried near and electrically connected to the pipeline to receive the same level of cathodic protection current as the pipeline. A test wire is connected to the pipeline and routed to a normally-closed contact switch located at an access point of a test station. The switch is also connected to a coupon wire, which is routed and connected to the coupon to complete the electrical connection. A reference electrode having a measuring surface contacting the soil close to the buried coupon includes an electrode wire provided to the access point. A voltmeter is connected between the switch and the reference electrode wire, and the switch is then opened to electrically isolate the coupon from the pipeline.

Abstract: An apparatus as provided for use in carrying out electrochemiluminescence test measurements. The apparatus includes a cell to contain an electrochemiluminescence sample fluid. A working electrode is provided within the cell and is coupled to a supply of electrical energy to apply the same to the sample fluid. A temperature effect adjustment system serves either to adjust a temperature of the electrochemiluminescent sample fluid so that it is within a predetermined range, or else adjusts an output signal representing light produced through electrochemiluminescence of the sample fluid based on the temperature of the sample fluid.

Abstract: An inactive state termination tester for determining the number of terminators connected to a bus when the bus is inactive. The termination tester monitors the bus for determining when it is inactive. During the periods of bus inactivity, the termination tester senses the bus to determine the number of terminators connected to the bus. The termination tester then displays how many terminators were detected.

Abstract: A Faraday cage enclosing the flow chamber of a cytometer and ground planes associated with each field deflection plate in concert therewith inhibit electric fields from varying the charge on designated events/droplets and further concentrates and increases forces applied to a charged event passing therethrough for accurate focus thereof while concomitantly inhibiting a potential shock hazard.

Abstract: A method and apparatus for automatically and rapidly, retrieving, counting and/or analyzing at least one selected white blood cell population and/or subset thereof of a whole blood sample or portion thereof. A volume of a biological sample containing the white blood cells is prepared and at least one reactant specific or preferential at least to some selected biological cells is introduced thereto and rapidly mixed for a short period of time. The opacity and/or volume parameter of the cells can be modified and the mixture is then counted and analyzed in one or more steps to obtain the desired white blood cell population analysis.The biological sample can be a whole blood sample and the reactant can include or be a lyse or a monoclonal antibody bound to microspheres, which will bind to specific ones of the cells or a combination of lyse and microspheres with antibody bound thereto.

Abstract: An "L" shaped element having horizontal and vertical sections, is submerged in the liquid toner concentrate such that the horizontal section is totally submerged while the vertical section is submerged proportionally to an amount of the liquid toner concentrate. A voltage source is connected to the "L" shaped element. A second element is placed in close proximity to the horizontal section of the "L" shaped element and is also totally submerged in the liquid toner concentrate. Next, a third element is placed in close proximity to the vertical section of the "L" shaped element. The current flowing from the horizontal section of the "L" shaped element through the liquid toner concentrate to the second element is proportional to the concentration of solid. By measuring the current flowing from the vertical section of the "L" shaped element through the liquid toner concentrate to the third element and dividing by the current in the second plate, the volume of the liquid toner concentrate can easily be calculated.

Abstract: The present invention concerns a method and apparatus for determining average particle size of silver halide grains in a solution or emulsion containing silver ions and excess halide ions. The potential of the silver ion in solution (E.sub.d) is measured using a silver electrode and the potential of the silver ion in solution with infinitely large silver halide particles (E.sub.e) is measured using a silver electrode coated with silver halide. The molecular volume (v) of the solute is calculated and the average particle size (d) is calculated from the following formula: ##EQU1## wherein F is the Faraday constant and (s) is the surface energy of the average particle size per unit area.

Abstract: A microprocessor (48) controlled triboelectric instrument with probe fouling detection, zero offset adjustments and temperature compensation. The system programmability provides for enhanced operator control and operator monitoring wherein the system may be reprogrammed to advantage to reduce instrument down time.

Abstract: With a view to enabling errors in the space potential to be automatically corrected by detecting a floating potential in each of a plurality of probes and to remove the errors in measurement based on the corrected space potential to thereby realize the accurate measurement of the space potential, there is provided a triple-probe plasma measuring apparatus, which comprises: a circuit for measuring electron temperature and electron density of a plasma with use of triple probes; a circuit for detecting and holding a floating potential difference; a differential voltage adding circuit; a fixed voltage source; and a change-over switch, the apparatus being capable of determining a difference in the floating potentials at the position of said probes, and superimposing the potential difference determined on the fixed voltage.

Abstract: The corrosion monitor system facilitates the detection and monitoring of material corrosion in remote areas. Sensors, which react to a corrosive environment similar to the material to be monitored, are placed in isolated areas and connected to a central control system via shielded cables. The system consists of a controller board, multiple dual preamp boards, a battery pack, sensors, and corresponding cables. The controller board consists of a microcontroller, memory, data conversion, and other control circuits. The dual preamp boards contain multiple precision instrumentation amplifiers, filtering, and voltage conversion circuits. The system operates on the principal that corrosion of a metallic conductor will cause a corresponding increase in the cross-sectional electrical resistance of that conductor. This change in resistance can be detected and monitored by passing a known constant current through the conductor and comparing the voltage across the conductor with that of a controlled reference conductor.

Abstract: A network-under-test of a device is tested relative to other networks of the device by probing the network-under-test with a probe; generating a voltage which is applied across the network-under-test via the probe for developing a transient voltage between the network-under-test and the other networks of the device for stressing leakage resistance between the network-under-test and the other networks; and determining if the stressed leakage resistance is acceptable for determining integrity of the network-under-test relative to the other networks of the device.

Abstract: A stylus assembly in which a stylus is mounted in a housing for movement relative thereto. An electrical circuit is provided for sensing contact of the stylus with a writing surface and measuring the pressure exerted on the surface by the stylus.

Abstract: Phosphorus concentration in molten copper can be determined by measuring temperature and electric resistivity of molten copper.

Abstract: A method for detecting extent of cross-linking of a high impedance polymer material during a pre-cure state, the method including: applying a test signal through a sensor to the material and through a reference resistance; determining a voltage difference between the test signal applied to the material and the reference resistance as the reference voltage; and correlating the voltage difference as a relative indicator of the extent of cross-linking which has occurred within the polymer material. Also disclosed is a device for implementing the subject method.

Abstract: A method for producing electrochemical impedance spectra. Spontaneously occuring coupling current noise between an array of electrodes which may be of substantially the same material is detected. A time domain record of the detected current noise is stored and the time domain record of the detected current noise is transformed to the frequency domain. Spontaneously occurring potential noise between the array of electrodes and a further electrode is detected. A time domain record of the detected potential noise is stored and the time domain record of the detected potential noise is transformed to the frequency domain. The frequency domain current noise and potential noise transformations are then transformed to the impedance domain to produce the required electrochemical impedance spectra.

Abstract: Devices and methods for determining the fatigue status of a metallic specimen are provided. The methods include contacting the specimen with-a cell containing an electrode and an electrolyte in contact with the specimen. A voltage is then applied, or galvanically created, between the specimen and the electrode, and the current is measured passing through the electrolyte during a period in which the specimen is subjected to cyclic stresses. A signature is then prepared which is representative of a measured current at the electrode, and the signature is analyzed to determine the fatigue status of the specimen.

Abstract: A MIS diode sensor having a Pd/Cu alloy electrode is sensitive to and can detect CO, H.sub.2, C.sub.2 H.sub.2 and C.sub.2 H.sub.4. An array of MIS diode sensors having varying electrode compositions can indicate a fault in an electrical transformer by the detection of at least one of the key fault gases CO, H.sub.2, C.sub.2 H.sub.2 and C.sub.2 H.sub.4.

Abstract: A sensor for measuring the mixture ratio of liquids, particularly of fuel mixtures, comprises a measuring cell, which has a cavity with one inlet and one outlet. The liquid is directed through the cavity, whereby regions of the inner wall of the cavity are electrically conductive and, together with at least one additional electrically conductive surface, form a capacitor, which is a component of an evaluation circuit. The measuring cell is manufactured from at least two ceramic carriers, which are connected by way of at least one connection layer to form a layer arrangement. The cavity is produced between the ceramic carriers as the result of the lack of at least one connection layer in certain regions. In each case, at least one electrode is applied, in the vicinity of the cavity, to the ceramic carrier delimiting the cavity using thick-film technology.

Abstract: A method capable of accurately and inexpensively measuring a very small quantity of impurities, such as water, contained in chemical substances, which are gaseous at normal temperature and pressure, is provided. A concentration of a very small quantity of impurities, contained in the chemical substances, which are gaseous at normal temperature and pressure, is measured by introducing the chemical substances into a cell under the condition of liquefied gases to measure an electric conductivity of the liquefied gases.

Abstract: A dissipation factor measurement is used to predict as-anodized fixture performance prior to actual use of the fixture in an etching environment. A dissipation factor measurement of the anodic coating determines its dielectric characteristics and correlates to the performance of the anodic coating in actual use. The ability to predict the performance of the fixture and its anodized coating permits the fixture to be repaired or replaced prior to complete failure.

Abstract: Apparatus for automated polyelectrolyte measurement of liquid process materials including a sample vessel which defines an electrically insulating, cylindrical cavity below a larger-diameter reservoir. Electrodes are located at the ends of the cylindrical cavity and an insulating piston is reciprocated with a predetermined, small clearance within the cavity. The charge displacement is measured between the electrodes. An outlet channel opening at the floor of the cylindrical cavity is connected to an outlet pipe. A rinsing duct with valve control for introducing a rinsing fluid into the reservoir. A controller is connected to an actuator for reciprocating the piston, to a valve in the outlet pipe and to the rinsing valve. After each polyelectrolyte measurement the substance under test is removed from the sample vessel through the outlet channel, rinsing fluid is introduced, and the rinsing fluid is removed through the outlet channel while the piston reciprocates.

Abstract: A probe for real-time in-situ monitoring for hot gas contaminants, such as alkali, uses the detection principles of condensation/vaporization temperatures or corrosion rates with electrical/optical measurements.

Abstract: A method for monitoring the state of, and for locating any detachment of, the protective covering of immersed or buried pipelines or other metal structures subjected to cathodic protection with constant current, on the basis of the overall electrical resistance offered by the pipeline/covering/ground system, consisting of applying local sinusoidal wave excitation currents of different frequencies to the pipeline and measuring the corresponding voltage responses, then comparing the measured responses of the system to determine, on the basis of response differences or coincidences at the various frequencies, whether within the portion under consideration there is detachment with corrosion underway or whether there is simple covering decay.

Abstract: The invention relates to an arrangement for monitoring the performance loss of an oxygen probe arranged forward of a catalytic converter. The oxygen probe supplies an actual voltage U.sub.-- ACT for a lambda controller for an internal combustion engine and the arrangement includes: a computation unit for computing the time-dependent mean value .vertline.U.sub.-- ACT-U.sub.-- DES .vertline. of the actual voltage U.sub.-- ACT from a desired voltage U.sub.-- DES; and, an evaluation unit for determining the performance loss of the oxygen probe on the basis of the time-dependent mean value. A simple method sequence which can be carried out with the above arrangement includes the step of deeming the probe to have an impermissibly high performance loss when the above-mentioned mean value drops below a threshold value. However, the quotient is preferably formed between the above-mentioned mean value and the mean value .vertline.FR.sub.-- ACT-FR.sub.-- DES.vertline.

Abstract: When textile materials are treated with wet processes, attempts are usually made to detect organic and inorganic contaminant substances retained in the cloth either by allowing conductivity-measuring or other electrodes placed on the cloth to travel with it during transport, or by analyzing the fluid squeezed out of the cloth. The data obtained by these methods are extremely unreliable and subject to interfering factors. As a substantial improvement, it is proposed that the loading of the cloth with extraneous substances be measured in the interior of the cloth, between or at its surfaces. This can be achieved by applying and collecting solvent to extract samples of the extraneous substances from the cloth, section by section, and measuring the extraneous substances in the collected solvent quantitatively and/or qualitatively.

Abstract: The use of a sacrificial anode in a plumbing system or in the cooling system of an internal combustion engine or the like to protect the system against the destructive effects of electrolysis caused by the many different metals employed in modern plumbing systems or engines is disclosed, along with several methods and apparatus for monitoring the condition of the sacrificial anode to indicate when replacement is needed for continued protection of the system. Physical, optical and electrical systems are taught, each designed to indicate the need for replacement of the anode in an easily discernable manner.

Abstract: A method for measuring a pressure dependent characteristic of a dispersion of a solid material in a fluid, comprising passing the fluid through a screen until a pad of the solid material is formed on the screen and, thereafter, measuring said characteristic, characterised in that the pressure on the screen side of the pad is maintained at a predetermined value, with respect to the pressure on the opposing side of the pad, during a measurement of the characteristic.

Abstract: A method is provided to monitor specific filtration resistance, total drainage resistance and drainage flow rate in a continuous on-line manner in the paper making process. It can be combined with the simultaneous measurement of streaming potential or zeta potential so as to enable optimization of the chemistry of the papermaking process.

Abstract: In a method and apparatus for examining samples comprising individual objects (28) of macromolecular or similar size, or smaller, an instrument element (14) comprises a substrate (16) overlaid with a thin film layer (18) of a material that is electrically conductive and/or at last partly optically opaque. A discontinuity comprising an aperture (26) or an asperity is formed in or on the element (14) in a known location, and the sample (28) is brought to this discontinuity so that it is not necessary to search for the sample by scanning. Energy (e.g. electrical energy or light) is applied to the element (14) and, with the latter and the sample in intimate association, e.g. with the sample inside the aperture (26), changes in the radiation from the sample site resulting from the presence of the sample are detected.

Abstract: A plasma diagnosing apparatus for performing plasma diagnosis witch probes having a high degree of cleanliness by removing contamination caused by reactive plasma, etc., while quantitatively detecting a degree of the contamination of the probes. The disclosed apparatus avoids the disadvantages of conventional apparatuses, in which the voltage-current characteristics of the probes are deteriorated by growth of the contaminant film formed on the probes, making it difficult to measure the parameters of the plasma conditions.

Abstract: The measurement of electrokinetic potential is of importance in paper-making. A measuring cell (12) for a specific potential known as streaming potential of the kind disclosed in EP B1 0 079 726 is now provided with measuring electrodes (40, 42) of a metal which forms a reversible electrochemical reaction with pure water to oxidize the metal. The electrodes (40, 42) used in the measurement mode in the cell have a film comprising an oxide of the metal electrochemically formed thereover. Such electrodes are found to give more stable and consistent measurement than the stainless steel electrodes used previously. Silver, lead, copper and alloys such as lead and silver are preferred. The measuring electrodes (40, 42) are regenerated within the cell (12) through electrochemical reduction to bare metal, followed by oxidation to re-form the film. This is performed with the aid of auxiliary electrodes (60, 62) in the cell. A control system (50) for the measurement and regeneration mode is described.

Abstract: An iron includes a heating element (97), heating control (11), for the heating element, and a control thermostat (13). To determine the type of fabric on which the iron is placed during ironing, the iron includes a type-of-fabric detector, which can be an electrostatic detector (35) or an optical detector (85). A maximum temperature limit T.sub.s defines the maximum ironing temperature of delicate fabrics. In the case of incorrect settings the operation of the iron is invalidated. The operation of the detector can be rendered dependent upon a humidity detector (60) which measures a resistivity of the fabric. The operation of these detectors (35, 85) may also depend on a detector for the state of use of the iron.

Abstract: A sheet size detection device for detecting a size of sheets which are held in a cassette body comprises a first guide member for defining the position of the sheets which are held in the body of the cassette, in a first direction of the sheets, the first guide member being movable in accordance with the size of sheets, a second guide member for defining the position of the sheets, in a second direction of the sheets, the second direction being orthogonal to the first direction, the second guide member being movable in accordance with the size of sheets, a first arm having a first resistor and movable with the first guide member, a second arm having a second resistor and movable with the second guide member, the first and second resistors constituting a variable resistor, and a size detector for detecting the size of the sheets on the basis of the resistance value of the variable resistor.

Abstract: A method for monitoring the soundness of the protective covering on underground metal structures subjected to cathodic protection, based on the electrical resistance offered by said covering, and consisting of modulating the imposed cathodic protection current and measuring the corresponding variation in potential due to the ohmic drop, said resistance being obtained from the ratio of the variation in potential to the modulation current.