USA As Represented by Secretary of the Navy

Curtis E Johnson

Kelvin T Higa

Richard A Hollins

David J Irvin

M Joseph Roberts

Thomas J Groshens

Roger M Sullivan

Scott K Johnson

Daniel C Harris

Robert W Schwartz

Thomas C Rozzell

Carl Durney

James Lords

A process to increase the fluidity of metal powders by surface modification with alkylsilane reagents. This invention generally discloses that the most efficient process results from treatment with methyltrichlorosilane in hexane. In particular, the fluidity of aluminum powders having mean diameters smaller than 10 micrometers was considerably improved by the process of embodiments of the invention.

Metal powders with improved flowability

A lead-free pyrotechnic and primary explosive compositions including metal iodates as an oxidizer in nanocomposite energetic compositions including metal powder fuel.

Lead-free pyrotechnic and primary explosive compositions containing metal iodates

The present invention demonstrates a superior, more economical, and scalable process to increase the fluidity of metal powders by surface modification with alkylsilane reagents. This invention discloses that the most efficient process results from treatment with methyltrichlorosilane in hexane. In particular, the fluidity of aluminum powders having mean diameters smaller than 10 micrometers was considerably improved by the process of the present invention. It is emphasized that this abstract is provided to comply with the rules requiring an abstract that will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope of the claims.

A method of making films surface imprinted with nanometer-sized particles to produce micro- and/or nano-structured electron and hole collecting interfaces, include providing at least one transparent substrate, providing at least one photoabsorbing conjugated polymer, providing a sufficient amount of nanometer-sized particles to produce a charge separation interface, providing at least one transparent polymerizable layer, embedding the nanometer-sized particles in the conjugated polymer, applying the polymerizable layer and the conjugated polymer/nanometer-sized particle mixture on separate substrates where the nanometer-sized particles form a stamp surface, imprinting the stamp surface into the surface of the polymerizable film layer to produce micro- and/or nano-structured electron and hole collecting interfaces, polymerizing the polymerizable film layer to form a conformal gap, and filling the gap with at least one photoabsorbing material to promote the generation of photoexcited electrons and transport to the charge separation interface.

Method for surface imprinted films with carbon nanotubes

A film surface imprinted with nanometer-sized particles to produce micro- and/or nano-structured electron and hole collecting interfaces, including: at least one substrate; at least one photoabsorbing conjugated polymer (including polybutylthiophene (pbT)) applied on a substrate, nanometer-sized particles including multiwalled carbon nanotubes (MWNT) to produce a charge separation interface; at least one transparent polymerizable layer, wherein the MWNT are embedded in the conjugated polymer to produce mixture and applied on a substrate to form a MWNT bearing surface film layer to form a stamp surface which is imprinted into the surface of the polymerizable film layer to produce micro- and/or nano-structured electron and hole collecting interfaces; polymerizing the polymerizable film layer to form a conformal gap between the MWNT stamp surface and the surface of the polymerizable film layer, and filling the gap with a photoabsorbing material to promote the generation of photoexcited electrons and transport to the charge separation interface.

Surface imprinted films with carbon nanotubes

Fine aluminum powders are prepared by decomposing alane-adducts in organic olvents under an inert atmosphere to provide highly uniform particles and believed particularly effective as fuels and additives, in pyrotechnics, and in energetic materials. Effective adduct species are trialkyl amines and tetramethylethylenediamine, ethers and other aromatic amines. Effective production is obtained at atmospheric pressure and at temperatures as low as 50.degree. C. with xylene solvent. Toluene, dioxane, and tetramethylethylenediamine were also effective solvents. Aliphatic solvents and other aromatic and polar solvents are believed effective. Titanium catalyst was provided as a halide, amide, and alkoxide; and it is believed that the corresponding compounds of zirconium, hafnium, vanadium, niobium, and tantalum are effective as catalysts. Particle size was controlled by varying catalyst concentration and by varying the concentration of an adducting species. It is believed that particle size is controllable by varying the catalyst, concentration of the reactants, polarity of the solvent, reaction temperature, and the stage and rate at which the solution is brought to this temperature. The product powder is passivated in the reaction vessel by exposing the solution to air before product separation or by controlling the admission of air to the separated, dried powder.

Selection of size of aluminum particles prepared by solution method

Fine aluminum powders are prepared by decomposing alane-adducts in organic solvents under an inert atmosphere to provide highly uniform particles selectably sized from about 65 nm to about 500 nm and believed particularly effective as fuels and additives, in pyrotechnics, and in energetic materials including composites, super thermite, and other explosives. Effective adduct species are trialkyl amines and tetramethylethylenediamine, ethers and other aromatic amines being believed effective. Effective production is obtained at atmospheric pressure and at temperatures as low as 50.degree. C. with xylene solvent. Increased production rate is achieved at higher temperatures. Toluene, dioxane, and tetramethylethylenediamine were also effective solvents. Aliphatic solvents and other aromatic and polar solvents are believed effective. Titanium catalyst was provided as a halide, amide, and alkoxide; and it is believed that the corresponding compounds of zirconium, hafnium, vanadium, niobium, and tantalum are effective as catalysts. Particle size was controlled by varying catalyst concentration and by varying the concentration of an adducting species, as by adding an amine to the solution or using an amine as the solvent. It is believed that particle size is controllable by varying the catalyst, concentration of the reactants, polarity of the solvent, reaction temperature, and the stage and rate at which the solution is brought to this temperature. The product powder is passivated in the reaction vessel by exposing the solution to air before product separation or by controlling the admission of air to the separated, dried powder.

Preparation of fine aluminum powders by solution methods

Finely divided metal sulfide powders of uniform size are produced at low temperatures by a method of adding solutions of organometallic compounds to an organic solvent saturated with H.sub.2 S. The solvent is kept saturated with H.sub.2 S by adding H.sub.2 S at a rate greater than that for the organometallic compound.

Low temperature synthesis of metal sulfides

A temperature probe measures temperature changes of biological tissue while he tissue is being irradiated with microwaves. The temperature probe is completely nonmetallic to minimize perturbation of the microwave field, and the structure of the probe includes a plurality of optic fibers which carry light to and from a reflective liquid crystal film. The liquid crystal is enclosed in a housing at the tip of the probe which is in contact with the biological tissue, and the liquid crystal undergoes changes in absolute reflectance proportional to the temperature changes of the tissue. The optic fibers are gathered in a bundle with a first portion of the bundle transmitting light from a light generation device to the liquid crystal and the remainder of the bundle transmitting reflected light from the crystal back to a photo transistor. The reflected light received by the photo transistor is converted into an electrical signal and displayed as a representation of temperature.

Growing community of inventors

Ridgecrest, CA, United States of America

Curtis E Johnson