The present invention relates to a mesoporous silica/ceria-silica composite and a method for preparing a mesoporous composite and, more specifically, to a mesoporous silica/ceria-silica composite which is composed of mesoporous silica having a hexagonal or cubic structure and ceria having a hexagonal structure provided on a surface and pores of the mesoporous silica, the oxidation state of the ceria being Ce.sup.4+ and Ce.sup.3+.

The present invention relates to a mesoporous silica/ceria-silica composite and a method for preparing a mesoporous composite and, more specifically, to a mesoporous silica/ceria-silica composite which is composed of mesoporous silica having a hexagonal or cubic structure and ceria having a hexagonal structure provided on a surface and pores of the mesoporous silica, the oxidation state of the ceria being Ce.sup.4+ and Ce.sup.3+.

The present application provides a method for recovering and reusing quartz powder waste in an out-of-tube deposition process. The quartz powder recovered by this method meets the optical performance requirements for the preparation of an optical fiber preform rod having a functional cladding, reduces the production cost, and solves the problem of environmental pollution. Also, the present invention further provides a method for preparing an optical fiber preform rod by using the recovered quartz powder. The method reduces and simplifies the difficulty in the manufacturing of a core rod of a preform rod, and simplifies the difficulty in the manufacturing of some preform rods of special structures.

A polymer inactivation method for a polycrystalline silicon manufacturing device, wherein the polymer byproducts are treated and additionally treated in a manner that controls the rate of reaction. The polymer byproducts are treated with a first inert gas under partial vacuum and a second oxygen containing gas to convert the polymer byproducts. The reaction rate can be controlled by regulating the fill pressure of reactant gas, controlling the amount of oxygen in the reactant gas, and stripping of the raw polymer with heat and or a vacuum. The solid byproduct remaining after treating the polymer, which is predominately silicon suboxides (SiO.sub.x) and silicon dioxide (SiO.sub.2), is inert and is easily removed.

A polymer inactivation method for a polycrystalline silicon manufacturing device, wherein the polymer byproducts are treated and additionally treated in a manner that controls the rate of reaction. The polymer byproducts are treated with a first inert gas under partial vacuum and a second oxygen containing gas to convert the polymer byproducts. The reaction rate can be controlled by regulating the fill pressure of reactant gas, controlling the amount of oxygen in the reactant gas, and stripping of the raw polymer with heat and or a vacuum. The solid byproduct remaining after treating the polymer, which is predominately silicon suboxides (SiO.sub.x) and silicon dioxide (SiO.sub.2), is inert and is easily removed.

Disclosed herein is a novel method to fabricate magnetic silica nanomembranes using thin polymer cores based on silica deposition and self-wrinkling induced by thermal shrinkage. These micro- and nano-scale structures have vastly enlarged the specific area of silica, thus the magnetic silica nanomembranes can be used for solid phase extraction of nucleic acids. The magnetic silica nanomembranes are suitable for nucleic acid purification and isolation and demonstrated better performance than commercial particles in terms of nucleic acid recovery yield and integrity. In addition, the magnetic silica nanomembranes may have high nucleic acid capacity due to significantly enlarged specific surface area of silica. Methods of use and devices comprising the magnetic silica nanomembranes are also provided herein.

Disclosed herein is a novel method to fabricate magnetic silica nanomembranes using thin polymer cores based on silica deposition and self-wrinkling induced by thermal shrinkage. These micro- and nano-scale structures have vastly enlarged the specific area of silica, thus the magnetic silica nanomembranes can be used for solid phase extraction of nucleic acids. The magnetic silica nanomembranes are suitable for nucleic acid purification and isolation and demonstrated better performance than commercial particles in terms of nucleic acid recovery yield and integrity. In addition, the magnetic silica nanomembranes may have high nucleic acid capacity due to significantly enlarged specific surface area of silica. Methods of use and devices comprising the magnetic silica nanomembranes are also provided herein.

According to the invention there is a method of depositing SiO.sub.2 onto a substrate by pulsed DC reactive sputtering which uses a sputtering gas mixture consisting essentially of oxygen and krypton.

According to the invention there is a method of depositing SiO.sub.2 onto a substrate by pulsed DC reactive sputtering which uses a sputtering gas mixture consisting essentially of oxygen and krypton.

Provided are methods of depositing silicon-containing films utilizing certain precursors at temperatures of 400° C. or higher. Certain methods comprise exposing a substrate surface to a silicon precursor and another precursor to achieve various films. Examples of silicon-containing films which can be deposited include SiN, SiC, SiO.sub.2, SiCN, etc.