Abstract: An apparatus includes a heat exchanger configured to transfer heat to a fluid and to absorb heat from the fluid as the fluid flows between a warm end and a cold end of a cryocooler. The heat exchanger includes at least one section having a substrate of at least one allotropic form of carbon and a layer of nanoparticles on or over the substrate. The heat exchanger could include multiple sections, and each section could include one of multiple substrates and one of multiple layers of nanoparticles. The heat exchanger can further include pores through the multiple sections of the heat exchanger, where the pores are configured to allow the fluid to flow through the heat exchanger and to contact the substrates and the layers of nanoparticles. The nanoparticles could include at least one lanthanide element or alloy, and the substrate could include carbon nanotubes or graphene.

Abstract: A method includes exposing a non-aqueous solution to ultraviolet illumination, where the non-aqueous solution includes one or more lanthanide elements and one or more photo-initiators. The method also includes producing lanthanide nanoparticles using the non-aqueous solution. The non-aqueous solution could be formed by mixing a first non-aqueous solution including the one or more lanthanide elements and a second non-aqueous solution including the one or more photo-initiators. The non-aqueous solution could include one or more metallic salts, where each metallic salt includes at least one lanthanide element. The one or more metallic salts could include erbium chloride, and the one or more photo-initiators could include benzophenone. The non-aqueous solution could include an organic solvent, such as an alcohol.

Abstract: An apparatus includes a heat exchanger configured to transfer heat to a fluid and to absorb heat from the fluid as the fluid flows between a warm end and a cold end of a cryocooler. The heat exchanger includes at least one section having a substrate of at least one allotropic form of carbon and a layer of nanoparticles on or over the substrate. The heat exchanger could include multiple sections, and each section could include one of multiple substrates and one of multiple layers of nanoparticles. The heat exchanger can further include pores through the multiple sections of the heat exchanger, where the pores are configured to allow the fluid to flow through the heat exchanger and to contact the substrates and the layers of nanoparticles. The nanoparticles could include at least one lanthanide element or alloy, and the substrate could include carbon nanotubes or graphene.

Abstract: An apparatus includes a heat exchanger configured to transfer heat to a fluid and to absorb heat from the fluid as the fluid flows between a warm end and a cold end of a cryocooler. The heat exchanger includes at least one section having a substrate of at least one allotropic form of carbon and a layer of nanoparticles on or over the substrate. The heat exchanger could include multiple sections, and each section could include one of multiple substrates and one of multiple layers of nanoparticles. The heat exchanger can further include pores through the multiple sections of the heat exchanger, where the pores are configured to allow the fluid to flow through the heat exchanger and to contact the substrates and the layers of nanoparticles. The nanoparticles could include at least one lanthanide element or alloy, and the substrate could include carbon nanotubes or graphene.

Abstract: An apparatus, method and thin-film structure for producing a blackbody spectrum is disclosed. A first layer of the apparatus is configured to generate heat in response to an applied voltage. A second layer is configured to emit the blackbody radiation spectrum in response to the heat from the first layer. A thermal spreading layer is disposed between the first layer and the second layer. The thermal spreading layer includes a graphene sheet for reducing a spatial variation of the heat in a plane of the thermal spreading layer.

Abstract: A method includes exposing a non-aqueous solution to ultraviolet illumination, where the non-aqueous solution includes one or more lanthanide elements and one or more photo-initiators. The method also includes producing lanthanide nanoparticles using the non-aqueous solution. The non-aqueous solution could be formed by mixing a first non-aqueous solution including the one or more lanthanide elements and a second non-aqueous solution including the one or more photo-initiators. The non-aqueous solution could include one or more metallic salts, where each metallic salt includes at least one lanthanide element. The one or more metallic salts could include erbium chloride, and the one or more photo-initiators could include benzophenone. The non-aqueous solution could include an organic solvent, such as an alcohol.

Abstract: An apparatus, method and thin-film structure for producing a blackbody spectrum is disclosed. A first layer of the apparatus is configured to generate heat in response to an applied voltage. A second layer is configured to emit the blackbody radiation spectrum in response to the heat from the first layer. A thermal spreading layer is disposed between the first layer and the second layer. The thermal spreading layer includes a graphene sheet for reducing a spatial variation of the heat in a plane of the thermal spreading layer.

Abstract: A family of adhesives is provided for bonding cyanate ester composite articles together which is also plateable with metal once chemically etched. The adhesives comprise a polymeric matrix and a filler of metal powder or metal flakes. The polymeric matrix comprises at least one polyepoxide resin and at least one curing agent. In practice, the present adhesive is applied to the surface of cyanate ester composite articles to be bonded and is allowed to cure in air at a temperature less than 125° C. Thereafter, the surface of the assembly is chemically etched and then plated with metal. The present adhesives enable the complete coverage of the cyanate ester composite assembly with the plated metal, including the adhesive bondlines. A cyanate ester resin structure assembled with the present adhesive composition may, upon plating, replace certain metallic components in such applications as aircraft, spacecraft, and automobiles given its highly conductive and comprehensive metallic coating.

Abstract: A resin composition for investment casting contains a moderate boiling temperature liquid inert diluent, having a boiling point in the range of about 200.degree. to 300.degree. C. The presence of the liquid inert diluent allows the resin to be used as a pattern, or model, in investment casting by preventing breaking of the mold during burnout of the resin. Any of the conventional resins suitable for stereolithography may be employed in the practice of the invention. To the resin is added a moderate boiling point solvent in the amount of about 5 to 30 wt %. Use of the moderate boiling point solvent in conjunction with the resin allows the pattern to shrink and crack at moderate temperature before final burnout. The shrinkage occurs faster and at a lower temperature as compared to the prior art.

Abstract: An improved process is provided for making optical limiters having a graded axial distribution of a reverse saturable absorber compound, such as a buckminsterfullerene, in a host matrix, such as polymethyl methacrylate or polycarbonate. The process of the invention includes: (a) dissolving the reverse saturable absorber and the host matrix in a suitable solvent to form a solution having a preselected ratio of reverse saturable absorber to host matrix; (b) casting the solution onto a surface to form a film; (c) evaporating the solvent to form a free-standing film; (d) performing steps (a)-(c) for each different desired ratio of reverse saturable absorber to host matrix; (e) stacking the free-standing films in a desired order; and (f) hot-pressing the stack to form the optical limiter having a graded distribution of the reverse saturable absorber in the host matrix. If desired, the stack of films can be placed in a die for hot-pressing. The films can be pre-cut to the shape of the die.

Abstract: Novel acetylene-terminated silicone monomers with (a) silane (Si--H) functionalities, (b) silanol (Si--OH) functionalities, or (c) (alpha,omega)phenylethynyl terminated siloxanes, and a novel synthetic route. The (alpha,omega)phenylethynyl-terminated siloxane monomers are prepared, starting with 1,3-bromobenzene, which is converted to 3-TMS-ethynylbromobenzene, where TMS represents the trimethylsilyl group, by reacting 1,3-dibromobenzene with trimethylsilylacetylene and triethylamine in the presence of a palladium catalyst. The 3-bromo-TMS protected phenyl acetylene is then reacted with an alkyllithium compound, such as n-butyllithium, or with magnesium to form the corresponding lithio or Grignard compound, respectively, followed by reaction with a halogenated compound, such as chlorodimethylsilane, to form 3-trimethylsilyl-ethynylphenyldimethyl silane.

Abstract: A fluxless solder for application to metal surfaces which include contaminants such as metal oxides. The fluxless solder includes a reducing agent which reacts with interfering metal oxides to form essentially inert compounds which require no further cleaning. Reducing agents, such as lithium, calcium, strontium and cesium are disclosed for use in lead-tin solders, in amounts ranging from about 0.5 to 10 atom percent. Various methods for forming the fluxless solder are also disclosed.

Abstract: Epoxy end-capped oligomers of 1,3-diolefin compounds of Formula I ##STR1## These oligomers are formed by: (a) reacting a 1,3-diolefin compound having 4 to 12 carbon atoms per molecule with a difunctional initiator comprising anionic reactive sites to form an intermediate living oligomer comprising two anionic end groups; and(b) reacting the intermediate living oligomer with a halohydrin compound to epoxidize the two anionic end groups and form the desired oligomer.The oligomers are subsequently reacted with an epoxidizing agent to form a polymer having epoxy-derived linkages at regular intervals along the chain of the polymer.

Abstract: A new group of silane compounds in which silicon atoms are linked together by a hydrocarbon chain and which comprise phenyl groups substituted with an epoxy group or an ethenyl group. The compounds of the present invention have the formula ##STR1## where R.sub.1 is selected from the group consisting of: (a) an aliphatic hydrocarbon group containing 2 to 10 carbon atoms, and(b) a group having the formula ##STR2## where n=1 to 3m=0 to 5;R.sub.2 and R.sub.2 ' are each selected from the group consisting of an alkyl group containing 1 to 4 carbon atoms, an unsubstituted aryl group, and a substituted aryl group; and R.sub.3 is selected from the group consisting of: ##STR3## where R.sub.4, R.sub.5, and R.sub.6 ae each selected from the group consisting of H, an alkyl group containing 1 to 4 carbon atoms, and an aryl group; and n=0 to 10.

Abstract: Improvement in the method for preparing resin compositions for use as a laminate material in printed wiring boards wherein the resin composition is formed by mixing an epoxy-anhydride prepolymer with maleated polybutadiene and a suitable solvent. The improvement involves preparing the epoxy-anhydride prepolymer using a two step procedure instead of a single step. The two step procedure prevents uncontrolled exothermic reactions from occurring during preparation of commercial quantities of the epoxy-anhydride prepolymer and increases the versatility of the process since different anhydrides can be used in each of the two steps.

Abstract: Methods for forming small diameter holes in polyimide/Kelvar.RTM. substrates utilize hot concentrated sulfuric acid and then honing, as necessary, with liquid abradant slurries to smooth uneven edges of the openings.

Abstract: A method for rendering a substrate resistant to erosion by a plasma comprising oxygen by providing on the surface of the substrate a layer of a cured polymer of a compound having the formula ##STR1## where: R.sub.1 is selected from the group consisting of:(a) an aliphatic hydrocarbon group containing 2 to 10 carbon atoms, and(b) a group having the formula ##STR2## wherein n=1 to 3 m=0 to 5R.sub.2 and R.sub.2 ' are each selected from the group consisting of an alkyl group containing 1 to 4 carbon atoms, an unsubstituted aryl group, and a substituted aryl group; and R.sub.

Abstract: A new group of silane compounds in which silicon atoms are linked together by a hydrocarbon chain and which comprise phenyl groups substituted with an epoxy group or an ethenyl group. The compounds of the present invention have the formula ##STR1## where R.sub.1 is selected from the group consisting of:(a) an aliphatic hydrocarbon group containing 2 to 10 carbon atoms, and(b) a group having the formula ##STR2## where n=1 to 3m=0 to 5;R.sub.2 and R.sub.2 ' are each selected from the group consisting of an alkyl group containing 1 to 4 carbon atoms, an unsubstituted aryl group, and a substituted aryl group;and R.sub.3 is selected from the group consisting of: ##STR3## where R.sub.4, R.sub.5, and R.sub.6 are each selected from the group consisting of H, an alkyl group containing 1 to 4 carbon atoms, and an aryl group; and n=0 to 10.

Abstract: Epoxysilicone compounds are prepared by first reacting a dibromobenzene compound with magnesium in anhydrous ether solvent to form a Grignard reagent and subsequently reacting the Grignard reagent with allyl bromide to form a (bromophenyl)propene compound. Next, the (bromophenyl)propene compound is converted to the corresponding Grignard reagent, which is then reacted with a compound of the formula I below ##STR1## where n=1 to 6,R.sub.1 and R.sub.2 are each chosen from the group consisting of a C.sub.1 to C.sub.4 alkyl group, a substituted aryl group, and an unsubstituted aryl group.in tetrahydrofuran solvent to form an allyl-terminated silicone compound of formula II below ##STR2## Finally, the allyl-terminated silicone compound is reacted with a chosen epoxidizing agent to form the epoxysilicone compound of formula III below.