Other

Center for Innovative Technology

The United States of America As Represented by the Administrator of the

Virginia Tech Intellectual Properties, Inc.

The United States of America As Represented by the United States

United States of America As Represented by the Administrator of Nasa

Aluminum Company of America

Virginia Polytechnic Institute and State University

Larry T Taylor

Anne K St Clair

James Rancourt

Robert A Frosch

Terry L St Clair

Cheol Park

Joycelyn S Harrison

Karl Wefers

Jae-Woo Kim

Jin Ho Kang

Godfrey Sauti

Diane M Stoakley

Peter T Lillehei

Sharon E Lowther

Stephen A Ezzell

Carlos Perry

James David Rancourt

Carlos V Perry, Jr

Maggie L Caplan

Harold G Boston

Negin Nazem

Mehdi Ashraf-Khorassani

Thomas A Furtsch

Vicki C Carver

Michael Z Martin

Charles C Johnson

Richard H Bott

A novel method to develop highly conductive functional materials which can effectively shield various electromagnetic effects (EMEs) and harmful radiations. Metallized nanotube polymer composites (MNPC) are composed of a lightweight polymer matrix, superstrong nanotubes (NT), and functional nanoparticle inclusions. MNPC is prepared by supercritical fluid infusion of various metal precursors (Au, Pt, Fe, and Ni salts), incorporated simultaneously or sequentially, into a solid NT-polymer composite followed by thermal reduction. The infused metal precursor tends to diffuse toward the nanotube surface preferentially as well as the surfaces of the NT-polymer matrix, and is reduced to form nanometer-scale metal particles or metal coatings. The conductivity of the MNPC increases with the metallization, which provides better shielding capabilities against various EMEs and radiations by reflecting and absorbing EM waves more efficiently. Furthermore, the supercritical fluid infusion process aids to improve the toughness of the composite films significantly regardless of the existence of metal.

Metallized nanotube polymer composite (MNPC) and methods for making same

This invention relates to methods of extracting and purifying bioactive substances from various plants and herbs. More specifically the invention relates to methods of extracting and separating bioactive substances from various plants and herbs, such as Kava root, Byrsonima species, , Pfaffia species, , Bursera species, Turnera species, Perezia species, , Psidium species, Enterlobium species, , and , using supercritical fluid extraction and/or fluorocarbon solvent extract. The present invention further relates to separation of bioactive substances contained in extracts using packed column supercritical fluid chromatography or HPLC where dense gas with or without modifiers is the mobile phase. The present invention also relates to pharmaceutical preparations and dietary supplements which may be prepared with the extracted bioactive substances and use of such pharmaceutical preparations and dietary supplements to treat various human ailments.

Pharmaceutical preparations of bioactive substances extracted from natural sources

Liquid gallium or gallium alloy is utilized as a mercury substitute for a variety of applications. The liquid gallium or gallium alloy is either free of metal oxides or has only very low quantities of metal oxides.

Non-toxic liquid metal composition for use as a mercury substitute

Polyimides with enhanced electrical conductivity are produced by adding a silver ion-containing additive to the polyamic acid resin formed by the condensation of an aromatic dianhydride with an aromatic diamine. After thermal treatment the resulting polyimides had surface conductivities in the range of 1.7.times.10.sup.-3 4.5 .OMEGA..sup.-1 making them useful in low the electronics industry as flexible, electrically conductive polymeric films and coatings.

Electrically conductive polyimides containing silver

A gallium-indium-zinc-copper metallic material has been found to exhibit many of the advantageous properties of mercury, such as electrical conductivity, fluidity, and high vaporization temperature. The metallic material is formulated by combining individual components in the presence of aqueous base, isolating the metallic phase, and heating the metallic combination. The metallic material is formulated to have sufficient quantities of each of the individual components such that the metallic material has a solidification temperature below 0.degree. C.

Metallic material with low melting temperature

Disclosed is a thermally-stable SnO.sub.2 -surfaced polyimide film wherein the electrical conductivity of the SnO.sub.2 surface is within the range of about 3.0.times.10.sup.-3 to about 1.times.10.sup.-2 ohms.sup.-1,. Also disclosed is a method of preparing this film from a solution containing a polyamic acid and SnCl.sub.4 (DMSO).sub.2.

Electrically conducting polyimide film containing tin complexes

Liquid gallium or gallium alloy is utilized as the conductive fluid in a switch or sensor housing. In order to prevent wetting of the interior walls of the switch or sensor housing, the liquid gallium or gallium alloy is either free of metal oxides or has only very low quantities of metal oxides.

Electrical switches and sensors which use a non-toxic liquid metal

With proper handling, Gallium-Indium-Tin eutectics are suitable for use as a substitute for mercury in switch applications. The eutectics should be acid washed to prevent oxidation of the metal components of the eutectic while in the switch housing and, further, the switch housing should be filled with an inert gas. Preventing oxidation ensures long term performance of the switch. In addition, provisions need to be made to prevent wetting of the switch housing by the eutectic. Experiments have shown that acid washing of metallic switch housings prior to adding the Gallium-Indium-Tin eutectic reduces or eliminates wetting by the eutectic. In addition, experiments have shown that coating the walls of the switch housing with a fluoropolymer coating prevents wetting by the eutectic.

Alloy substitute for mercury in switch applications

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.

Flow through voltammetric analyzer and method using deoxygenator

Electrical joint compounds for the protection of electrical connections are formed from a solution of polymer dissolved in solvent with or without conductive filler. Partially cured thermosetting polymers are preferred as they flow under service conditions to better seal the electrical joints. Thermosetting polymers which cure by an addition mechanism are preferred over those which cure by condensation, and polyimides are most preferred.

Method of making electrical connections using joint compound

A zero dead volume (ZDV) microbore high performance liquid chromatography (.mu.HPLC)/Fourier transform infrared (FTIR) interface flow cell includes an IR transparent crystal having a small diameter bore therein through which a sample liquid is passed. The interface flow cell further includes a metal holder in combination with a pair of inner, compressible seals for directly coupling the thus configured spectrometric flow cell to the outlet of a .mu.HPLC column end fitting to minimize the transfer volume of the effluents exiting the .mu.HPLC column which exhibit excellent flow characteristics due to the essentially unencumbered, open-flow design. The IR beam passes transverse to the sample flow through the circular bore within the IR transparent crystal, which is preferably comprised of potassium bromide (KBr) or calcium fluoride (CaF.sub.2), so as to minimize interference patterns and vignetting encountered in conventional parallel-plate IR cells. The long IR beam pathlength and lensing effect of the circular cross-section of the sample volume in combination with the refractive index differences between the solvent and the transparent crystal serve to focus the IR beam in enhancing sample detection sensitivity by an order of magnitude.

Liquid chromatography/Fourier transform IR spectrometry interface flow

This invention relates to improved lightweight, high temperature resistent, electrically conductive, palladium containing, polyimide films and methods of preparing same for use in aerodynamic and space application. A palladium (II) ion-containing polyamic acid solution is prepared by reacting an aromatic dianhydride with an equimolar quantity of a palladium II ion-containing salt or complex and the reactant product is cast as a thin film onto a surface and cured at approximately 300.degree. C. to produce a flexible electrically conductive cyclic palladium containing polyimide. The source of palladium ions is selected from the group of palladium II compounds consisting of LiPdCl.sub.4, Pd[S(CH.sub.3).sub.2 ].sub.2 Cl.sub.2,Na.sub.2 PdCl.sub.4, and PdCl.sub.2.

Electrically conductive palladium containing polyimide films

A method for preparing an aluminum ion-filled polyimide adhesive wherein a meta-oriented aromatic diamine is reacted with an aromatic dianhydride and an aluminum compound in the presence of a water or lower alkanol miscible ether solvent to produce an intermediate polyamic acid; and thereafter converting the polyamic acid to the thermally stable, metal ion-filled polyimide by heating in the temperature range of 300.degree. C. to produce a flexible, high temperature adhesive.

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Blacksburg, VA, United States of America

Larry T Taylor