Abstract: A Sigma Rho A/D converter (10) includes a transconductance element (R) having an input node for receiving an input voltage signal V.sub.in and an output node providing an analog current I.sub.in ; a charge integrator (12) having an input coupled to the output node, the charge integrator having feedback provided by an integrating capacitor C and an output node providing an output signal V.sub.o ; and a clocked voltage comparator (14) having an input coupled to V.sub.o for comparing V.sub.o to a reference potential. An output of the comparator updates in response to an occurrence of a first clock signal CLK1. A current sink (16) is switchably coupled to the output node of the transconductance element as a function of the logic state of the output of the comparator.

Abstract: A glass fiber laser system includes a laser resonator cavity having a resonant path and an erbium-doped glass fiber lasing element with an output of from about 1.5 to about 1.6 micrometers within the laser resonator cavity. A light source directed into an input end of the glass fiber lasing element optically pumps the lasing element to emit light. A passive Q-switch lies along the resonant path within the laser resonator cavity. The Q-switch is formed of a host material having a concentration of uranium ions therein, so as to be a saturable absorber of the light emitted by the lasing element. The Q-switch is preferably a uranium-doped fluoride crystal such as U:CaF.sub.2, U:SrF.sub.2, or U:BaF.sub.2.

Abstract: A high power, flip-chip microwave monolithic integrated circuit (MMIC) assembly (30) has a high power microwave monolithic integrated circuit (MMIC) having a surface with an active area (72) in which heat is generated. The assembly also has a host substrate (34). A thermally conductive bump (51) formed over the surface of the MMIC has a first portion (51') in close proximity to and in thermal communication with the active area (72) of the MMIC and a second portion (51") which is in close proximity to and in thermal communication with the host substrate (34). The second portion (51") of the thermal bump (51) has a greater cross-sectional area than the first portion (51'). A multi-layer, multi-exposure method of manufacturing the improved thermal bump (51) includes several steps. A plating membrane (80) is formed on a surface of the MMIC (32). A first layer of negative photoresist is applied to the surface of the plating membrane (80), and is exposed with a first masked pattern of light.

Abstract: A thermal electrochemical system in which an electrical current is generated between a cathode immersed in a concentrated aqueous solution of phosphoric acid and an anode immersed in a molten salt solution of ammonium phosphate and monohydric ammonium phosphate. Reactants consumed at the electrodes during the electrochemical reaction are thermochemically regenerated and recycled to the electrodes to provide continuous operation of the system.

Abstract: Bonding of polystyrene foam details together to produce lost foam molds suitable for casting metallic details is accomplished by coating one of the two mating surfaces of the parts with a phenol-formaldehyde adhesive. The two parts are joined together and the mated assembly is placed in a microwave oven. Exposure of the assembly to microwave energy for a pre-selected period of time effects the bonding.

Abstract: A process for removing undesired sub-micrometer particulates from a chosen substrate (16) comprising the steps of: (a) placing the substrate containing the undesired particulates in a cleaning chamber (12) provided with megasonic energy-producing means (20); (b) introducing a liquefied gas (22), such as liquid carbon dioxide, into the cleaning chamber and contacting the substrate containing the undesired particulates with the liquid carbon dioxide at a temperature below its critical temperature; and (c) exposing the liquid carbon dioxide to the megasonic energy-producing means for a period of time sufficient to remove the undesired particulates from the substrate. The substrate containing the undesired particulates may optionally be contacted with carbon dioxide in the dense phase prior to and/or after the treatment with megasonic energy to aid in removal of the undesired particulates.

Abstract: An integrated circuit testing system for testing small quantities of integrated circuit die. The testing system includes an integrated circuit tester and a base printed wiring board interface that physically and electrically interfaces thereto. A die holder that holds an integrated circuit die is coupled to the base printed wiring board interface. A flexprint structure including first and second flexible contact structures is provided that electrically connect to the base printed wiring board interface, to pads on the integrated circuit die, and to each other to provide for electrical connection between the tester and the die. A plurality of alignment pins are provided for aligning the first and second flexible contact structures to each other and to the pads on the integrated circuit die.

Abstract: A composition for removing organic contaminants, such a flux residues, from a solid substrate comprises: (a) hydrogen peroxide in the amount of about 3 to 5 percent by weight of the composition; (b) an alkaline compound in sufficient amount to provide a pH of at least 10.5 in the composition; (c) about 0.1 to 0.3 percent by weight of a chosen wetting agent which is unreactive with the hydrogen peroxide and the alkaline compound; and (d) purified water as the balance of the composition. Optionally, the composition may further comprise about 0.5 to 2.0 percent by weight of a chosen metal protective agent.The solid substrate having organic contaminants thereon is exposed to the above noted composition whereby the organic contaminants are removed from the substrate and are converted into non toxic and non-hazardous products. Thus, negative environmental impact is avoided by the present process.

Abstract: A method for removing contaminants from a solid substrate comprising, in a preferred embodiment:(a) providing an initial reaction bath comprising:(1) an alkaline compound in sufficient amount to provide a pH of 10.5 to 14.0 in the final reaction bath;(2) a chosen wetting agent which is stable in the presence of the alkaline compound and hydrogen peroxide; and(3) deionized water;(b) metering hydrogen peroxide into the initial and final reaction baths at a rate of about 0.004 milligrams of hydrogen peroxide per minute per gallon of reaction bath fluid or higher;(c) sparging the initial and final reaction baths with air or oxygen at a rate of about 0.001 to 1 standard cubic feet per minute; and(d) exposing the substrate having contaminants to the final reaction bath containing metered hydrogen peroxide and sparging air or oxygen.

Abstract: An improved method for the preparation of very high molecular weight polycarborane siloxane polymers in which each of the reactants is first provided in an ultra-pure state by a series of recrystallization procedures in specific solvents. The reactants are then reacted in the following series of steps by:(a) providing ultra-pure carborane bisdimethyl silanol in dried chlorobenzene solvent, to form a slurry and cooling said slurry to -10.degree..+-.5.degree. C.;(b) adding to said slurry a mixture of ultra-pure dimethylbisureido silane and ultra-pure methylphenylbisureido silane to form a reaction mixture at -10.degree..+-.5.degree. C.

Abstract: A composition for removing organic contaminants, such a flux residues, from a solid substrate comprises: (a) hydrogen peroxide in the amount of about 3 to 5 percent by weight of the composition; (b) an alkaline compound in sufficient amount to provide a pH of at least 10.5 in the composition; (c) about 0.1 to 0.3 percent by weight of a chosen wetting agent which is unreactive with the hydrogen peroxide and the alkaline compound; and (d) purified water as the balance of the composition. Optionally, the composition may further comprise about 0.5 to 2.0 percent by weight of a chosen metal protective agent. The solid substrate having organic contaminants thereon is exposed to the above-noted composition whereby the organic contaminants are removed from the substrate and are converted into non-toxic and non-hazardous products. Thus, negative environmental impact is avoided by the present process.

Abstract: An method of providing a protective coating on the surface of aluminum or aluminum alloys, comprising: removing contaminants from the surface; exposing the surface to water at 50.degree. to 100.degree. C. to form a porous boehmite coating on the surface; and exposing the boehmite-coated surface to an aqueous solution comprising a cerium salt and a metal nitrate at a temperature of 70.degree. to 100.degree. C. Oxides and hydroxides of cerium are formed within the pores of the boehmite to provide the protective coating, which provides corrosion resistance and improved paint adhesion.

Abstract: An electrode apparatus for use in an electrochemical cell, which permits hydrogen gas generated at the cathode to be recirculated directly to the anode. The electrode apparatus comprises:(a) an ion-permeable membrane separating the anode and cathode compartments and liquids contained therein;(b) hydrogen electrodes (cathode and anode) in their respective compartments and in contact with the membrane, comprising a porous hydrophobic catalytic structure which permits the passage of hydrogen gas both along and perpendicular to the longitudinal surface of the electrode, and having an external portion extending outside of the elctrode compartment and exposing the edge surface of the electrode; and(c) a gas chamber connected to the external portions of the electrodes and providing for transfer of gas from the cathode directly to the anode.

Abstract: Polymers of silanol-terminated aromatic imide compounds of Formula I ##STR1## where R.sub.3 and R.sub.4 are each selected from the group consisting of a C.sub.1 to C.sub.6 alkyl group, an unsubstituted aryl group and a substituted aryl group, Z is a divalent radical.A preferred copolymer in accordance with the present invention is formed by polymerizing the compound of Formula I with a silicon compound having the formula ##STR2## where R.sub.3 and R.sub.4 are as defined above, X=halogen, OH, OR, NRR, or ureido,Y=--O-- or ##STR3## p=1 to 10.

Abstract: Silanol-terminated aromatic imide compounds of Formula I ##STR1## where R.sub.3 and R.sub.4 are each selected from the group consisting of a C.sub.1 to C.sub.6 alkyl group, an unsubstituted aryl group and a substituted aryl group, Z is a divalent radical.are prepared by:(a) reacting a bromoaniline compound with a chosen silylating agent to form a compound having the formula BrC.sub.6 H.sub.5 NSi(R.sub.1).sub.3 Si(R.sub.2).sub.3, where R.sub.1 and R.sub.2 are each a C.sub.1 to C.sub.4 alkyl group(b) reacting the compound formed in step "a" with n-butyllithium, followed by reaction with a chosen halogenated alkylsilane compound to form a compound having Formula II ##STR2## where R.sub.1, R.sub.2, R.sub.3, and R.sub.4 are as defined above (c) reacting the compound of Formula II formed in step "b" with a dianhydride compound having the formula ##STR3## where Z is as defined above to form a compound having Formula III ##STR4## where R.sub.3, R.sub.

Abstract: A process for removing undesired material from a chosen substrate by exposing the substrate simultaneously to ultraviolet radiation and a selected dense fluid, wherein the radiation produces a photochemical reaction that removes the undesired material from the substrate and the dense fluid enhances the removal of the undesired material. In an alternative embodiment, a reactive agent may additionally be used. The process may be used to remove contaminants from a substrate, etch a substrate surface, or destroy toxic organic material in industrial wastes.

Abstract: A method and composition which provides both thermal control and electrostatic discharge protection to bodies in the space environment. The composition comprises: a) a chosen polymer or resin that forms a polymer that is an electronic insulator and is suitable for space applications; and b) a selected lithium salt as a dopant wherein said composition, when formed into a film or coating, provides a semiconductive film or coating having a volume resistivity of about 10.sup.6 to 10.sup.11 ohm-centimeter and a value of solar absorptance/total normal emittance within the range of about 0.305 to 0.595. In an alternative embodiment, the composition may optionally include tantalum pentoxide.

Abstract: A thermal transfer adhesive composition which is applied after electronic components have been installed on a printed wiring board, comprising:(a) 30 to 70 weight percent of an aliphatic diisocyanate or triisocyanate prepolymer;(b) 5 to 15 weight percent of a polyether diol or triol;(c) 20 to 40 weight percent of castor oil;(d) 5 to 20 weight percent of an epoxy resin containing 2 or more hydroxyl group;(e) 0.006 to 0.008 weight percent of a catalyst for the reaction of isocyanate groups with hydroxyl groups. The cured product is hydrolytically stable at 185.degree. F. and 95 percent relative humidity and has a good storage life when frozen. Alternatively, the composition may also include a pigment.

Abstract: A methane Raman cell is provided with a catalytic composite comprising palladium on a titania substrate, which promotes the hydrogenation of gas products formed by the decomposition of methane from arcing, and thereby inhibits the reaction of these gas products to form deposits which adhere to the windows of the Raman cell. This Raman cell has greatly increased life. In an alternative embodiment, further improvements may be obtained by adding hydrogen dopant gas to the methane.

Abstract: Silanol-terminated aromatic imide compounds of Formula I ##STR1## where R.sub.3 and R.sub.4 are each selected from the group consistsing of a C.sub.1 to C.sub.6 alkyl group, an unsubstituted aryl group and a substituted aryl group, Z is a divalent radical.are prepared by: (a) reacting a bromoaniline compound with a chosen silylating agent to form a compound having the formula BrC.sub.6 H.sub.5 NSi(R.sub.1).sub.3 Si(R.sub.2).sub.3, where R.sub.1 and R.sub.2 are each a C.sub.1 to C.sub.4 alkyl group(b) reacting the compound formed in step "a" with n-butyllithium, followed by reaction with a chosen halogenated alkylsilane compound to form a compound having Formula II ##STR2## where R.sub.1, R.sub.2, R.sub.3, and R.sub.4 are as defined above (c) reacting the compound of Formula II formed in step "b" with a dianhydride compound having the formula ##STR3## where Z is as defined above to form a compound having Formula III ##STR4## where R.sub.3, R.sub.