Abstract: A production method of amorphous silicon oxide powder comprises a step of preparing a wood, agricultural crop or plant containing hexose and/or pentose and silicon oxide as a starting raw material, a step of hydrolyzing the starting raw material with nitric acid, hydrochloric acid, sulfuric acid, phosphoric acid or organic acid to reduce a content of the hexose to 10% by weight or less and/or a content of the pentose to 20% by weight or less, and a step of burning residue yielded in the hydrolyzing step at a temperature of 400° C. to 1200° C.

Abstract: Pyrogenically produced silica powder with a BET surface of 30 to 90 m2/g, a dibutyl phthalate number of at least 80 and a tamped density of no more than 110 g/l. It is produced in that at least one vaporous silicon compound, a gas containing free oxygen and a combustible gas are mixed together in a closed burner and then burnt in a flame in the flame tube of the burner, the solid obtained is separated from the gas mixture and optionally purified, wherein the oxygen content of the gas containing free oxygen is adjusted such that the lambda value is greater than or equal to 1, and the gamma value is between 1.2 and 1.8. It can be used in toner applications.

Abstract: Pyrogenically produced silicon dioxide powder with a specific surface area of between 5 and 600 m2/g and a carbon content of less than 500 ppm, which displays a specific dibutyl phthalate absorption of less than or equal to 1.2 g dibutyl phthalate/100 g SiO2 per m2 of specific surface area and a specific thickening action of less than 15 mPas/m2 of specific surface area. It is produced by supplying vaporous tetramethoxysilane and/or tetraethoxysilane together with air and separately hydrogen to a burner, and allowing the mixture of gases to react in a flame in a reaction chamber connected in series to the burner, and separating the solid reaction product from the gas stream by known means, the lambda value in the burner being between 0.95 and 1.5 and sufficient secondary air also being supplied to the reaction chamber that the lambda value in the reaction chamber is between 0.8 and 1.6.

Abstract: The invention relates to a method for making silica nanoparticles using a flame reactor, which includes a droplet spray having a two-fluid nozzle and a burner of a quintuple tube structure. In this method, droplets of silicon alkoxide as liquid Si compound are sprayed through the droplet spray of the flame reactor. A flame is generated by the flow of inert gas, oxygen, hydrogen and air simultaneously into the burner of the flame reactor. The liquid Si compound is delivered through the flame of the burner to produce silica nanoparticles having a mean particle size ranging from 9 nm to 68 nm. Resultant nanoparticles are collected and recovered in a particle collector. The droplets sprayed under high pressure from a silicon alkoxide solution are directly oxidized in the flame, thereby producing spherical silica nanoparticles.

Abstract: The invention relates to a method for making silica nanoparticles using a flame reactor, which includes a droplet spray having a two-fluid nozzle and a burner of a quintuple tube structure. In this method, droplets of silicon alkoxide as liquid Si compound are sprayed through the droplet spray of the flame reactor. A flame is generated by the flow of inert gas, oxygen, hydrogen and air simultaneously into the burner of the flame reactor. The liquid Si compound is delivered through the flame of the burner to produce silica nanoparticles having a mean particle size ranging from 9 nm to 68 nm. Resultant nanoparticles are collected and recovered in a particle collector. The droplets sprayed under high pressure from a silicon alkoxide solution are directly oxidized in the flame, thereby producing spherical silica nanoparticles.

Abstract: A hydrophobic fumed silica treated with a cyclic dimethylsiloxane, the hydrophobic fumed silica having an M-value representing an oleophilic degree in a range of 48 to 65, a tapping bulk density of not smaller than 80 g/L but not larger than 130 g/L, and an n-value representing the dispersion of 3.0 to 3.5 as measured in toluene. The hydrophobic fumed silica features a high bulk density while exhibiting a high hydrophobic property, the powder thereof capable of being favorably handled, being easily mixed in a matrix such as of a resin within short periods of time, and, further, being dispersed in the matrix to a high degree.

Abstract: A high dispersible hydrophobic fine silica powder can be made, wherein the silica powder has hydrophobicity of more than 50%, triboelectrostatic charge of more than ?500 ?C/g, decomposition rate of an organic group on the powder surface of less than 15%, transmittance of a 5% alcoholic dispersion liquid of more than 40% preferably, and a specific surface area of more than 200 m2/g. This high dispersible hydrophobic fine silica powder can be made by mixing a hydrophobic agent comprising a volatile organic silicon compound in the gas state with a fine silica powder in a fluidized bed type reaction vessel at the time of a hydrophobic treatment, and controlling a gas flow rate to more than 5.0 cm/sec at the time of this mixing.

Abstract: Pyrogenically produced silicon dioxide powder in the form of aggregates of primary particles having a BET surface area of 200±25 m2/g, wherein the aggregates display an average surface area of 7000 to 12000 nm2, an average equivalent circle diameter (ECD) of 80 to 100 nm and an average circumference of 850 to 1050 nm. It is produced by a pyrogenic process in which silicon tetrachloride and a second silicon component comprising H3SiCl, H2SiCl2, HSiCl3, CH3SiCl3, (CH3)2SiCl2, (CH3)3SiCl and/or (n-C3H7)SiCl3 are mixed with primary air and a combustion gas and burnt into a reaction chamber, secondary air also being introduced into the reaction chamber, and the feed materials being chosen such that an adiabatic flame temperature of 1570 to 1630° C. is obtained. It can be used as a filler.

Abstract: The present invention herein provides fine inorganic hollow powder having a high hollowness rate, which can be incorporated into, for instance, a low dielectric rubber or resin composition. The inorganic hollow powder has an average hollowness rate of higher than 70% by volume and an average particle size ranging from 3 to 20 ?m and the powder preferably has an average hollowness rate ranging from 75 to 85% by volume, an average particle size ranging from 5 to 15 ?m, a maximum particle size of not more than 25 ?m, a specific surface area of not more than 10 m2/g, an average sphericity degree of not less than 0.90 and a purity of not less than 99% by mass.

Abstract: A process of preparing a biogenic silica comprising the steps of incinerating a silica bearing organic source at a temperature up to 1200° C. and allowing the incinerated silica organic source to cool; adding the incinerated and cooled silica bearing organic source to an alkaline solution that has either been preheated to a temperature up to about 65° C. or to be heated with the added organic source to a temperature up to about 65° C., the alkaline solution being contained in a vessel and having a pH up to 14; applying heat so that the added organic source and the alkaline solution in the vessel are at a temperature between 100° C. and up to about 300° C. for 1 to 4 hours, thereby forming an aqueous biogenic silica and undissolved impurities derived from the added organic source; and extracting the aqueous biogenic silica from the vessel. The extracted silica can be solidified into a solid form.

Abstract: Process for preparing pulverulent solids, in which one or more oxidizable and/or hydrolysable metal compounds are reacted in a high-temperature zone in the presence of oxygen and/or steam, the reaction mixture is cooled after the reaction, and the pulverulent solid is removed from gaseous substances, wherein at least one metal compound is introduced into the high-temperature zone in solid form and the evaporation temperature of the metal compound is below the temperature of the high-temperature zone.

Abstract: A method of forming a gel and/or powder of a metallic oxide, metalloid oxide and/or a mixed oxide or resin thereof from one or more respective organometallic liquid precursor(s) and/or organometalloid liquid precursor(s) by oxidatively treating said liquid in a non-thermal equilibrium plasma discharge and/or an ionised gas stream resulting therefrom and collecting the resulting product. The non-thermal equilibrium plasma is preferably atmospheric plasma glow discharge, continuous low pressure glow discharge plasma, low pressure pulse plasma or direct barrier discharge. The metallic oxides this invention particularly relates to are those in columns 3a and 4a of the periodic table namely, aluminium, gallium, indium, tin and lead and the transition metals. The metalloids may be selected from boron, silicon, germanium, arsenic, antimony and tellurium.

Abstract: Pyrogenically produced silicon dioxide powder in the form of aggregates of primary particles having a BET surface area of 150±15 m2/g, wherein the aggregates display an average surface area of 12000 to 20000 nm2, an average equivalent circle diameter (ECD) of 90 to 120 nm and an average circumference of 1150 to 1700 nm. It is produced by a pyrogenic process in which silicon tetrachloride and a second silicon component comprising H3SiCl, H2SiCl2, HSiCl3, CH3SiCl3, (CH3)2SiCl2, (CH3)3SiCl and/or (n-C3H7)SiCl3 are mixed with primary air and a combustion gas and burnt into a reaction chamber, secondary air also being introduced into the reaction chamber, and the feed materials being chosen such that an adiabatic flame temperature of 1670 to 1730° C. is obtained. Silicone sealing compound containing the pyrogenically produced silicon dioxide powder.

Abstract: The crude oil reserves have a time limit which may be calculated. Before the automobile industry, aviation, the weapons industry, and space travel change their combustion engines over to silanes, for example, hydrogen peroxide will preferably be used as an energy carrier. The hydrogen peroxide may be obtained especially advantageously from a power plant process according to the present invention, in which hydrocarbons contaminated with sulfur are used for combustion. The present invention also relates to a novel system for transporting/conveying hydrogen peroxide.

Abstract: Pyrogenically produced silicon dioxide powder in the form of aggregates of primary particles having a BET surface area of 300±25 m2/g, wherein the aggregates display an average surface area of 4800 to 6000 nm2, an average equivalent circle diameter (ECD) of 60 to 80 nm and an average circumference of 580 to 750 nm. It is produced by a pyrogenic process in which silicon tetrachloride and a maximum of up to 40 wt. % of a second silicon component comprising H3SiCl, H2SiCl2, HSiCl3, CH3SiCl3, (CH3)2SiCl2, (CH3)3SiCl and/or (n-C3H7)SiCl3 are mixed with primary air and a combustion gas and burnt into a reaction chamber, secondary air also being introduced into the reaction chamber, and the feed materials being chosen such that an adiabatic flame temperature of 1390 to 1450° C. is obtained. It can be used as a filler.

Abstract: Pyrogenic silicon dioxde powder with a BET surface area of 30 to 90 m2/g, a DBP index of 80 or less, a mean aggregate area of less than 25000 nm2 and a mean aggregate circumference of less than 1000 nm, wherein at least 70% of the aggregates have a circumference of less than 1300 nm, It is prepared by mixing at least one silicon compound in vapour form, a free-oxygen-containing gas and a combustible gas in a burner of known construction, igniting this gas mixture at the mouth of the burner and burning it in the flame tube of the burner, separating the solid obtained from the gas mixture and optionally purifying, wherein the oxygen content of the free-oxygen-containing gas is adjusted so that the lambda value is greater than or equal to 1, the gamma value is between 1.2 and 1.8, the throughput is between 0.1 and 0.3 kg SiO2/m3 of core gas mixture and the mean normalised rate of flow of gas in the flame tube at the level of the mouth of the burner is at least 5 m/s. The powder can be used as a filler.

Abstract: A hydrophobic silica fine powder is prepared by premixing a hydrophilic silica fine powder with a dimer diol siloxane or cyclic siloxane as a hydrophobizing agent, mixing them in a ball mill for achieving dispersion and for achieving cleavage or disintegration and consolidation, and thereafter heating at 100-300° C. in an ammonia or amine-containing atmosphere. The powder has an aerated bulk density of 100-300 g/l, a specific surface area of 40-300 m2/g, a primary particle diameter of 10-120 nm, and a degree of hydrophobization of 40-80 as measured by methanol titration and is less bulky, easy to handle and disperse and stable in a kneaded mixture.

Abstract: A fumed-silica, which can make a slurry having sufficient wettability to a polar liquid, excellent dispersibility, and low viscosity even in the high concentration, and a slurry thereof. A fumed-silica and its slurry are provided, wherein the water content is controlled so that a weight loss after drying Y, and a dynamic wetting rate to water Z, have specified values.

Abstract: Composite microparticles having thin coating layers can be simply prepared by bringing a host particle precursor into contact with a flame generated in a burner movably mounted at the bottom of a coating apparatus, by introducing the precursor in the form of a vapor or micronized liquid droplets upwardly into the burner, to obtain host particles; and introducing a gaseous coating precursor upwardly toward the host particles in or around the flame, the coating precursor being protected by an inert gas introduced therearound such that the formation of particles derived from the coating precursor itself is prevented.

Abstract: A high concentration silica slurry can be used for polishing of substrates, such as semiconductor materials. The slurry contains a silica powder dispersed in an solvent. The silica slurry has a silica concentration of more than 50% by weight and a viscosity of less than 1000 mPa·s, wherein the silica powder has a ratio DL/DT of less than 1.3, wherein DL is an average particle size of the silica powder measured by a laser diffraction particle size distribution method and DT is an average primary particle size of the silica powder measured by a TEM photography observation, and wherein the silica powder has an average primary particle size of from 0.08 ?m to 0.8 ?m.

Abstract: A method of forming a catalyst body by forming a first layer of hemispherical grain polysilicon over a substrate, and oxidizing at least a portion of the first layer to form a second layer of silica. Additionally, forming a third layer of nitride material over the second layer, and forming a catalyst material over the nitride layer, can be performed before annealing to form a catalyst body.

Abstract: The present invention relates to a metal oxide powder for high precision polishing and prepartion thereof, comprising aggregates formed by cohesion of primary particles, which has a cohesive degree (?) of 1.1 to 2.0 and a cohesive scale (?) of 3 to 10, the cohesive degree (?) and the cohesive scale (?) being defined by formula (I) and formula (II), respectively: ?=6/(S×?×d(XRD)) ??(I) ?=weight average particle diameter/d(XRD) ??(II) wherein, S is the specific surface area of the powder; ?, the density; and d(XRD), the particle diameter of the powder determined by X-ray diffraction analysis. In accordance with the present invention, it is possible to provide a high polishing speed and reduce scratches.

Abstract: The amorphous-silica particle having 0.1–0.7 ?m of the average particle diameter, 5–30 m2/g of the specific surface area, less than 40% of the dispersion coefficient, and 20 ?C/m2 of the absolute value of the triboelectrostatic charge, can be obtained, by setting flame temperature to more than melting point of silica, raising the silica concentration in a flame, and staying the generated silica particle in the flame for a short time to be grew up. Since this silica particle has a particle shape being near a true sphere, and a particle size of said particle is remarkably uniform, so it is suitable for a filler of a semiconductor sealing agent or various materials, etc. In addition, since said particle has strong electrification, it is also suitable for an outer or an inner additional agent of a toner for an electronic photograph, a photo conductor material for a electronic photograph, and a material of an electric charge transportation layer, etc.

Abstract: A surface modified fine silica powder which has been treated, preferably, with a treating agent containing an amino group, characterized in that the powder exhibits an adsorption amount for an anion source compound of 150% or more of that of an original powder which has not been treated; and a printing material using the silica powder. The surface modified fine silica powder can provide an excellent printed matter being free from blotting with ink or a cracking of coating film.

Abstract: A method of forming a catalyst body by forming a first layer of hemispherical grain polysilicon over a substrate, and oxidizing at least a portion of the first layer to form a second layer of silica. Additionally, forming a third layer of nitride material over the second layer, and forming a catalyst material over the nitride layer, can be performed before annealing to form a catalyst body.

Abstract: Particulate silica is prepared by feeding a gas mixture of an organohalosilane gas, a flammable gas capable of generating water vapor when burned, and a free oxygen-containing gas to a reaction chamber through a multiple-tube burner, whereby the organohalosilane is subjected to flame hydrolysis and oxidation reaction. The amount of the flammable gas fed is 0.5-9 mol per mol of the organohalosilane and such that the amount of water vapor resulting from combustion of the flammable gas is 1-6 times the stoichiometric amount, and the gas mixture is fed to the center tube of the burner such that it may have a linear velocity at the outlet of 50-120 m/sec, calculated in the standard state. The resulting silica has a surface area of 100-400 m2/g and a narrow particle size distribution of primary particles and ensures the transparency of silicone rubber filled therewith.

Abstract: A lithium ion secondary cell having a high capacity, improved first charge/discharge efficiency and improved cycle performance is obtainable using as the negative electrode material a lithium-containing silicon oxide powder having the formula: SiLixOy wherein x and y are 0<x<1.0 and 0<y<1.5, with the lithium being fused and partially crystallized.

Abstract: Pyrogenically prepared silica doped with silver or silver oxide is prepared by feeding an aerosol into a flame such as is used for the preparation of pyrogenic silica, mixing the aerosol homogeneously with gas mixture before the reaction, then allowing the aerosol/gas mixture to react in a flame. The resulting pyrogenic silicas doped with silver or silver oxide are separated from the gas stream. The pyrogenic silica doped with silver or silver oxide by means of an aerosol can be used as a bactericidal filler.

Abstract: The invention provides a process for forming a low k fluorine and carbon-containing silicon oxide dielectric material by reacting with an oxidizing agent one or more silanes that include one or more organofluoro silanes selected from: (a) an organofluoro silane containing two silicon atoms linked by one oxygen atom; (b) an organofluoro silane containing two silicon atoms linked by one or more carbon atoms, where the one or more carbon atoms each are bonded to one or more fluorine atoms, or to one or more organofluoro moieties, or to a combination thereof; and (c) an organofluoro silane containing a silicon atom bonded to an oxygen atom. The invention also provides a process for forming a low k fluorine and carbon-containing silicon oxide dielectric material by reacting with an oxidizing agent one or more silanes that include one or more organofluoro silanes characterized by the presence of Si—O bonds.

Abstract: The invention provides a process for producing fumed metal oxide particles comprising providing a stream of a liquid feedstock comprising a volatizable, non-halogenated metal oxide precursor, providing a stream of a combustion gas having a linear velocity sufficient to atomize and combust or pyrolyze the liquid feedstock, and injecting the stream of the liquid feedstock into the stream of combustion gas to form a reaction mixture such that the liquid feedstock is atomized and subjected to a sufficient temperature and residence time in the combination gas stream for fumed metal oxide particles to form before the combustion gas temperature is reduced below the solidifying temperature of the metal oxide particle. The invention further provides fumed silica particles having a relatively small aggregate size and/or narrow aggregate size distribution.

Abstract: A method and furnace are described for producing a fused oxide body by decomposing a precursor compound of the oxide in a flame to form molten oxide particles and collecting those particles in a furnace constructed of a refractory material to form a fused oxide body, the improvement in the method comprising treating the refractory material with a strong acid in liquid form to react with, and thereby remove, contaminants from at least the surface of the refractory material.

Abstract: A silicon oxide powder represented by the formula: SiOx wherein 1.05≦x≦1.5 and having a BET specific surface area of 5-300 m2/g is useful as a negative electrode material to construct a lithium ion secondary cell having a high capacity and improved cycle performance.

Abstract: Hydrophobic silica fine powder is produced by pyrolyzing a silane compound to form a silica fine powder and hydrophobizing the silica fine powder with an organohalosilane in a fluidization vessel. Hydrophobized silica fine powder which flies out of the fluidization vessel is collected with a cyclone and bag filter which are held at a temperature of 100-500° C. An apparatus for carrying out the process is also provided. Under simple controlled conditions that involve holding the cyclone and bag filter for recovering fugitive silica from the fluidization vessel to temperatures of 100-500° C., the method and apparatus are able to recover essentially 100% of fugitive silica, thus increasing yield of the product and alleviating the burden on waste gas treatment.

Abstract: The present invention is directed to methods of producing soot used in the manufacture of optical waveguides. Both non-aqueous liquid reactants and aqueous solutions containing one or more salts are delivered through an atomizing burner assembly to form a homogenous soot stream containing the oxides of the selected elements contained within the non-aqueous liquid reactant and the aqueous solution. The resulting multi-component soot is collected by conventional methods to form preforms used in the manufacture of optical waveguide fibers. Preforms formed by the methods are also disclosed.

Abstract: The present invention relates to a method for production of amorphous silica from particulate materials containing at least 50% elemental silicon, where the silicon-containing material is supplied to a combustion reactor which is heated by an oil- or gas burner and where amorphous silica is recovered after the outlet from the combustion reactor. At least a part of the particulate silicon containing materials are supplied to the combustion reactor in the form of an aqueous slurry. The invention further relates to an apparatus for production of amorphous silica.

Abstract: Hydrophobic silica fine powder is produced by pyrolyzing a silane compound to form a silica fine powder and hydrophobizing the silica fine powder with an organohalosilane as hydrophobizing agent in a fluidization vessel. A portion of the silica fine powder is bypassed to a waste gas line from the fluidization vessel and collected with a cyclone and bag filter, and the collected powder is fed to the fluidization vessel where it is hydrophobized. The amount of unreacted organohalosilane in the waste gases is reduced, alleviating the burden on waste gas treatment. The silica having the unreacted organohalosilane borne thereon is fed back to the fluidization vessel, increasing the reaction efficiency of organohalosilane.

Abstract: The present invention relates to a method for producing microsilica having a reflectivity between 65 and 90% in a smelting furnace for production of ferrosilicon or silicon by using a charge comprising an SiO2 source and a solid carbonaceous reduction agent, where microsilica is recovered from the off-gases from the smelting furnace, wherein the solid reduction agent supplied to the furnace contains an amount of volatile matters of less than 1.25 kg per kg produced microsilica and that the temperature in the gas atmosphere in the furnace above the charge is kept above 500° C.

Abstract: A method for extracting silica of more than 99.99% purity from rice bran includes the steps of: washing rice bran in water and removing impurities floated on the water; sequentially washing the rice bran in an acid solution and water more than twice; dehydrating the washed rice bran under pressure; drying the dehydrated rice bran; burning the dried rice bran at a temperature of 350˜400° C. while being agitated and pulverized; and burning the rice bran at a temperature of 700˜1000° C. for 10˜60 minutes while being agitated by providing oxygen or air. The soot, a by-product detrimental to the environment, generated during burning the rice bran in the process of extracting silica, can be effectively removed.

Abstract: The present invention provides a two stage process of thermal separation of CFCs and HCFCs followed by vitrification of the waste into a commercially viable glass. In the first stage, the hydrogenated compounds are reacted at elevated temperature with water and a metal oxide such as calcium oxide to form a halide salt and carbon dioxide. In the second stage of the process, the brine slag is reacted at elevated temperature with the carbon dioxide from stage one and glass-forming raw materials such as silicon dioxide to produce a glass. The final glass product incorporates the halide into the glass.

Abstract: The amorphous-silica particle having 0.1-0.7 &mgr;m of the average particle diameter, 5-30 m2/g of the specific surface area, less than 40 of the dispersion coefficient, and 20 &mgr;C/m2 of the absolute value of the triboelectrostatic charge, can be obtained, by setting flame temperature to more than melting point of silica, raising the silica concentration in a flame, and staying the generated silica particle in the flame for a short time to be grew up. Since this silica particle has a particle shape being near a true sphere, and a particle size of said particle is remarkably uniform, so it is suitable for a filler of a semiconductor sealing agent or various materials, etc. In addition, since said particle has strong electrification, it is also suitable for an outer or an inner additional agent of a toner for an electronic photograph, a photo conductor material for a electronic photograph, and a material of an electric charge transportation layer, etc.

Abstract: Burners (40) for producing fused silica boules are provided. The burners employ a tube-in-tube (301-306) design with flats (56, 50) on some of the tubes (305, 301) being used to limit the cross-sectional area of certain passages (206, 202) within the burner and/or to atomize a silicon-containing, liquid source material, such as OMCTS. To avoid the possibility of flashback, the burner has separate passages for fuel (205) and oxygen (204, 206), i.e., the burner employs nozzle mixing, rather than premixing, of the fuel and oxygen. The burners are installed in burner holes (26) formed in the crown (20) of a furnace and form a seal with those holes so that ambient air cannot be entrained into the furnace through the holes. An external air cooled jacket (60) can be used to hold the temperature of the burner below a prescribed upper limit, e.g., 400° C.

Abstract: The present invention is directed to a method for making fused silica glass. A liquid, preferably halide-free, silicon-containing compound capable of being converted by thermal oxidative decomposition to SiO2 is provided and introduced directly into the flame of a combustion burner, thereby forming finely divided amorphous soot. The amorphous soot is deposited on a receptor surface where, either substantially simultaneously with or subsequently to its deposition, the soot is consolidated into a body of fused silica glass. The invention further relates to an apparatus for forming fused silica from liquid, preferably halide-free, silicon-containing reactants which includes: a combustion burner which, in operation, generates a flame; an injector for supplying a liquid silicon-containing compound to the flame to convert the compound by thermal oxidative decomposition to a finely divided amorphous soot; and a receptor surface on which the soot is deposited.

Abstract: Spherical, non-crystalline silica particles made by burning a non-halogenated siloxane starting material are substantially halogen-free, and have a content of metallic impurities other than silicon of not more than 1 ppm, a particle size of 10 nm to 10 &mgr;m and a specific surface area of 3-300 m2/g. Production of the particles is carried out by oxidative combustion of the non-halogenated siloxane in a flame at a high adiabatic flame temperature to effect the formation of a large number of core particles and promote their coalescence and growth.

Abstract: A silane composition for preparing a semiconductor thin films of a solar cell is disclosed. The silane composition contains a polysilane compound represented by the formula SinRm (n is an integer of 3 or more, m is an integer of n to (2n+2) and an m number of R's are each independently a hydrogen atom, alkyl group, phenyl group or halogen atom, with the proviso that when all the m number of R's are hydrogen atoms and m=2n, n is an integer of 7 or more), and at least one silane compound selected from cyclopentasilane, cyclohexasilane and silylcyclopentasilane.

Abstract: An oxidation exhaust trap for filtering a particulate product of a first gas contacted with a gaseous oxidizing agent. The oxidation exhaust trap has a vessel having an interior cavity. The vessel further having a first inlet in communication with the interior cavity for introduction of the first gas into the interior cavity and a second inlet in communication with the interior cavity for introduction of the gaseous oxidizing agent into the interior cavity, the gaseous oxidizing agent mixing with the first gas thereby causing oxidation of the first gas for producing the particulate product suspended in a gaseous product. Lastly, the vessel has an outlet in communication with the interior cavity. A filter is disposed in the interior cavity for filtering the particulate product from the gaseous product which is exhausted through the outlet. In a preferred embodiment of the present invention, the first gas is silane and the gaseous oxidizing agent is air.

Abstract: A method for extracting silica of more than 99.99% purity from rice bran includes the steps of: washing rice bran in water and removing impurities floated on the water; sequentially washing the rice bran in an acid solution and water more than twice; dehydrating the washed rice bran under pressure; drying the dehydrated rice bran; burning the dried rice bran at a temperature of 350˜400° C. while being agitated and pulverized; and burning the rice bran at a temperature of 700˜1000° C. for 10˜60 minutes while being agitated by providing oxygen or air. The soot, a by-product detrimental to the environment, generated during burning the rice bran in the process of extracting silica, can be effectively removed.

Abstract: A process for continuously preparing finely divided refractory oxides having a particle specific surface area of less than about 100 m2/g from an oxygen containing reactant gas and at least one reactant selected from the group consisting of vaporous salts of silicon, titanium, aluminum, zirconium, iron and antimony, wherein at least one of the reactant materials is heated by means of a plasma generator which produces a temperature in the range of from about 3,000°-to about 12,000° C., and the reactants are combined and passed into a reaction zone for a period of from about 0.001 to about 1.0 second to give the oxide product. The oxygen-containing gas stream comprises from about 100 to about 105% of the stoichiometric amount of oxygen based on the vaporous salt and from about 10 to about 150%, based on oxygen, of a gaseous diluent which is inert under reaction conditions.

Abstract: A process for producing ultra fine silica particles, the process comprising directing a plasma jet onto a silicon-containing compound thereby to form silica vapor and condensing the silica vapor on a collection surface.

Abstract: Water-repellent porous silica having uniform pores, which comprises silica skeleton wherein fluorine atoms are fixed through covalent bonds and which has an alkali metal content of not more than 10 ppb, is synthesized. By the water-repellent porous silica, a water-repellent porous silica film having uniform pores, which is applicable to a light functional material or an electron functional material, a process for preparing the same and uses thereof can be provided.

Abstract: This invention relates to the production of high purity fused silica glass through oxidation or flame hydrolysis of a vaporizable silicon-containing compound. More particularly, this invention is directed to the use of vaporizable, halide-free compounds in said production. In the preferred practice, a polymethylsiloxane comprises said vaporizable, halide-free compound.