Hughes Aircraft Company

Raytheon Company

He Holdings, Inc.

John McHardy

Carl W Townsend

Clifford A Megerle

Frank A Ludwig

Lin R Higley

John M Brauninger

J Brian Murphy

Andrew Kindler

Stephen A Gabelich

Thomas P Moser

The composition of an electrically conductive mixture, such as a mixture of gasoline and alcohol, is measured using a single measurement cell having a first electrode and a second electrode with a measurement space therebetween for receiving a specimen of the mixture. With a specimen of the mixture in the measurement space, the first electrode is alternatively connected to a reference discharge voltage, preferably ground, and to an applied voltage through a resistor. A first operational state encompasses the period when the first electrode is connected to the reference discharge voltage and a second operational state encompasses the period when the first electrode is connected to the applied voltage through the resistor. A first operational state peak voltage is measured during the first operational state, and a second operational state peak voltage is measured during the second operational state. The first operational state peak voltage and a preselected constant proper fraction of the second operational state peak voltage are summed to obtain a summed voltage output, which may be correlated to the composition of the mixture.

Dielectric mixture composition sensor with compensation for mixture

The composition of an electrically conductive mixture, preferably a mixture of gasoline and alcohol, is measured using a single measurement cell having a first electrode and a second electrode with a measurement space therebetween for receiving a specimen of the mixture. With a specimen of the mixture in the measurement space, the first electrode is alternatively connected to a reference discharge voltage, preferably ground, and to a feedback control voltage. A first operational state encompasses the period when the first electrode is connected to the reference discharge voltage and a second operational state encompasses the period when the first electrode is connected to the feedback control voltage. A first operational state peak voltage is measured during the first operational state, and a peak second operational state voltage is measured during the second operational state. The first operational state voltage and a preselected constant proper fraction of the peak second operational state voltage are mathematically combined to obtain a voltage output, which may be correlated to the composition of the mixture. The voltage output is also used as the feedback control voltage, to produce a linear signal output as a function of dielectric constant of the conductive mixture.

Dielectric mixture composition linear sensor with compensation for

A simple robust sensor probe for determining the magnesium concentration in molten metal alloys in real-time. The probe provides needed process control information in molten metal technologies and has particular application to processes for removing magnesium impurities from scrap aluminum. The probe employs a specially constructed electrochemical concentration cell adapted for repeated immersions into vessels containing molten metal alloys. Specifically, the probe comprises two electrodes, both inert to a molten salt layer, to the molten metal (aluminum), and to magnesium. One electrode comprises an inverted molybdenum cup, a magnesium reference material, and a fibrous ceramic wick, e.g., yttrium oxide, for retaining molten salt therein in contact with the magnesium reference material when the sensor probe is first inserted into the molten salt layer and then into the molten aluminum layer. A readout between the two electrodes provides a measure of the electromotive force and thus a measure of the concentration of magnesium in molten aluminum during demagging of the molten aluminum.

Measuring magnesium concentrations in molten metal alloys

An improved device for monitoring the presence of toxic metals in workplace air comprises a base and a removable top assembly. The top assembly includes a test substrate, such as filter paper, having a first surface and a second surface. The first surface is supported by the top assembly and the second surface has an area that is sensitized with at least one chemical reagent for producing a reaction with at least one toxic metal. The base has an air inlet, an air outlet, and a channel connecting the air inlet and the air outlet, thereby enabling air entering the monitor from the air inlet to directly contact the area of the second surface of the test substrate prior to exiting the monitor through the air outlet.

Time averaged toxic metals monitoring method

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.

Real-time toxic metals monitor device and method

Precise information about the position of a liquid-liquid interface (28, 32) is often important for the control and automation of molten metal refining processes. For example, in an electrolytic process for removing magnesium from molten aluminum, knowledge of the vertical position of an interface (32) between the electrolyte and the magnesium and an interface (28) between the electrolyte and the aluminum facilitates the automatic removal of the purified metals. Differences in surface tension in the fluid layers of a molten electrolytic salt (30) and a molten metal (29) produce different pressures as bubbles (57) evolved from vertically displaced tips (52) of tubes (34, 36) press against the liquid layers on either side of their interfaces (28, 32). These different pressures are detected by a differential pressure transducer (42) to limit the amount of purified molten aluminum from molten aluminum-magnesium scrap, when drawn through a port (26) in a reaction furnace (10) without risk of also contaminating the purified aluminum with the electrolyte (30) above the interface.

Method and apparatus for detecting the position of liquid-liquid

An electrochemical synapse adapted for use in a neural network which includes an input terminal and an output terminal located at a distance of less than 100 microns from the input terminal. A permanent interconnect having controllable conductivity is located between the two inputs. The conductivity of the permanent interconnect is controlled by either growing or eliminating metallic whiskers between the inputs. The growth and elimination of whiskers provides a rapid and controllable electrochemical synapse. Partial neural network systems are disclosed utilizing the electrochemical synapse.

Electrochemical synapses for artificial neural networks

A method for evaluating characteristics of a printed wiring board by measuring the alternating current impedance spectra of the printed wiring board conductor pattern. The method is useful in evaluating a number of different characteristics, such as moisture content, delamination, interlayer thickness and surface characteristics.

Non-destructive method for evaluation of printed wiring boards

An electrochemical capacitor (battery-capacitor) which provides high power density and rapid charging and discharging times ranging from a few milliseconds to a few seconds. The capacitor device includes at least one electrochemical cell having two electrodes and an electrolyte therebetween. The electrodes and electrolyte are capable of rapid redox kinetics with the electrodes being spaced apart by no more than 0.002 inch (5.08.times.10.sup.-3 cm) to thereby provide rapid charging and discharging times.

Growing community of inventors

Westlake Village, CA, United States of America

John McHardy