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Du Fresne, E. R.

Publications and source records attributed to Du Fresne, E. R..

Pressure-Sensitive Resistor Material

Low-conductivity particles in rubber offer wide dynamic range. Sensor consists of particles of relatively low conductivity embedded in rubber. Resistance of sensor decreases by about 100 times as pressure on it increases from zero to 0.8 MN/M to the second power. Resistor promising candidate as tactile sensor for robots and remote manipulators.

Du Fresne, E. R.

Reinforcing the Separators for Lithium/Carbon Cells

Fabrication of lithium/carbon batteries simplified by attachment of perforated nickel-foil, graphite-cloth, or graphite-paper backings to glass-fiber separators. Both nickel and carbon backings appear viable. Because perforated nickel foil already manufactured by electroforming, no obstacle to creation of very thin, very porous nickel foil to serve as backing: Thicknesses of 20 micrometers with porosities above 50 percent practicable.

Du Fresne, E. R.

Lightweight Protective Garments

Proposed garment material protects wearer from poisonous chemicals, bacteria, and radioactive particulates. Garment allows heat, moisture, and carbon dioxide to pass from inside to outside so wearer remains comfortable. Garment made of cotton fabric on which thin layer of polyacrylate rubber is deposited by calendering or spraying. Lighter and cooler than existing protective garments. Polyacrylate rubber selected for garment material because it transmits water vapor and carbon dioxide at high rates.

Du Fresne, E. R.

Purifying Aluminum by Vacuum Distillation

Proposed method for purifying aluminum employs one-step vacuum distillation. Raw material for process impure aluminum produced in electrolysis of aluminum ore. Impure metal melted in vacuum. Since aluminum has much higher vapor pressure than other constituents, boils off and condenses on nearby cold surfaces in proportions much greater than those of other constituents.

Du Fresne, E. R.

Multipurpose Photonic Transducers

Features include smallness and noise immunity. Photonic transducer is interferometer with two arms. Small relative axial motions of mirrors detected as shifts in interference pattern. Version measures temperature changes via differential expansion or contraction of stalks. New transducers smaller (typical size less than 1 cm) and coupled to monitoring equipment with optical fibers instead of wires. Well suited to biomedical instrumentation.

Du Fresne, E. R.

Degreaser Reduces Solvent Loss

Escape of solvent minimized by second cooling coil. Degreaser suppresses solvent-vapor loss through parts-basket dragout and air drafts. Within C02 blanket, convection repeatedly exposes C02/solvent mixture to cold spot created by C02 coil. Solvent vapor condenses, then runs down via through to cold tank. This small expenditure of C02 minimizes health and environmental hazards.

Du Fresne, E. R.

Optical Logic Gates

Logic gates for light signals constructed from combinations of prisms, polarizing plates, and quarterwave plates. Optical logic gate performs elementary logic operation on light signals received along two optical fibers. Whether gate performs OR function or exclusive-OR function depends on orientation of analyzer. Nonbinary truth tables also obtained by rotating polarizer or analyzer to other positions or inserting other quarter-wave plates.

Du Fresne, E. R.

Recovering Zinc From Discarded Tires

Zinc sulfate monohydrate sold at profit. Shredded tire material steeped in three sulfuric acid baths to extract zinc. Final product removed by evaporating part of solution until product crystallizes out. Recovered as zinc sulfate monohydrate and sold as fertilizer or for general use.

Du Fresne, E. R.

Evaporation Tower With Prill Nozzles

Tower more efficient than conventional evaporation equipment. Liquids such as milk and fruit juice concentrated by passing them through tiny nozzle to form droplets, then allowing droplets to fall through evacuated tower with cooled walls.

Du Fresne, E. R.

Removing Biostatic Agents From Fermentation Solutions

Liquid carbon dioxide inexpensive solvent. Inexpensive process proposed for removing such poisons as furfural and related compounds from fermentation baths of biomass hydrolysates. New process based on use of liquid carbon dioxide as extraction solvent. Liquid CO2 preferable to such other liquid solvents as ether or methylene chloride.

Du Fresne, E. R.

A contaminated meteorite

Meteorite contaminated with biogenic materials - plant fragments, hydrocarbons, and water soluble proteins

METEORITIC COMPOSITION