Abstract: The invention concerns article having a surface oxide layer up to 20 nm thick, the surface oxide layer comprising chromium and cobalt oxides where the atomic ratio of Cr/Co is more than 3. The invention also concerns methods for treating a chromium containing material, said method comprising contacting said material with a gas plasma under conditions effective to oxidize at least a portion of the material; and contacting said material with an acid. The treated surface is corrosion resistant and can be used in orthopedic implants, especially the wear surface of the orthopedic implant to reduce wear, and other corrosive environment.

Abstract: A catalyst comprising a zeolite loaded with copper ions and at least one trivalent metal ion other than Al+3, wherein the catalyst decreases NOx emissions in diesel exhaust. The trivalent metal ions are selected from, for example, trivalent transition metal ions, trivalent main group metal ions, and/or trivalent lanthanide metal ions. In particular embodiments, the catalysts are selected from Cu—Fe-ZSM5, Cu—La-ZSM-5, Fe—Cu—La-ZSM5, Cu—Sc-ZSM-5, and Cu—In-ZSM5. The catalysts are placed on refractory support materials and incorporated into catalytic converters.

Abstract: Compositions and methods are provided for preparing a metal substrate having a uniform textured surface with a plurality of indentations with a diameter in the nanometer and micrometer range. The textured surface is produced by exposing the substrate to an etching fluid comprising a hydrogen halide acid and/or an oxyacid, a chloride containing compound, and an oxidizing agent. The etching solution can be used at ambient temperature without damaging the metal elements on the substrate surface. This textured surface enhances adherence of coatings or cells onto the textured surface, improves the retention of proteins on the surface, and encourages bone in-growth.

Abstract: A method for generating a user mobility model includes: firstly deriving user movement tracks of all the users in a cellular network and then generating from the user movement tracks a user mobility model involving a user traffic between home cells of any two of path points in the cellular network. Thus, a cell can be re-divided into respective location areas according to the generated user mobility model to thereby deploy reasonably various network resources in the GSM network according to the re-divided positional zones. The invention further discloses a method and device for generating a user movement track and a device for generating a user mobility model.

Abstract: The present invention concerns processes for etching a porous titanium foam or porous titanium alloy foam where a clean, dry foam product is immersed into an aqueous acid solution comprising about 0.5 to about 5 volume percent HF and about 5 to about 20 volume percent HNO3 for a time sufficient to achieve a desired surface roughness and heating the etched foam to remove residual titanates. The etching process increases the porosity at the surface of the foam but the etchant does not penetrate fully into the interior of the foam so that adequate mechanical properties are maintained. The etching process also increases the coefficient of friction at the foam surface. The foam may comprise an open-celled orthopaedic or dental implant, or may comprise a coating on the surface of a substrate.

Abstract: Methods and devices directed to surface treatment of implants are disclosed. In some instances, the surfaces are treated to have one or more characteristics that can impart low wear properties when the implant is utilized in a subject. As one example, a metallic surface of an implant can be treated to form pits in the surface, followed optionally by a smoothing step to reduce the roughness of the pitted surface. A plasma treatment can be used to form an oxide-containing layer (e.g., highly corrosion resistant and/or thick) on the surface. An acid treatment can also be used as part of a process for forming an oxide-containing layer. Other examples of method are also disclosed, along with characteristics of implant surfaces that can exhibit low wear properties.

Abstract: Disclosed is a method of preparing a medical implant. The biocompatible metal surface of the implant is subjected to electrochemical etching in an electrolyte solution to which a current has been applied.

Abstract: The invention concerns article having a surface oxide layer up to 20 nm thick, the surface oxide layer comprising chromium and cobalt oxides where the atomic ratio of Cr/Co is more than 3. The invention also concerns methods for treating a chromium containing material, said method comprising contacting said material with a gas plasma under conditions effective to oxidize at least a portion of the material; and contacting said material with an acid. The treated surface is corrosion resistant and can be used in orthopedic implants, especially the wear surface of the orthopedic implant to reduce wear, and other corrosive environment.

Abstract: Compositions and methods are provided for preparing a metal substrate having a uniform textured surface with a plurality of indentations with a diameter in the nanometer and micrometer range. The textured surface is produced by exposing the substrate to an etching fluid comprising a hydrohalic acid and a mixture of a hydrohalic acid and an oxyacid, a chloride containing compound, and an oxidant. The etching solution can be used at ambient temperature. This textured surface enhances adherence of coatings or cells onto the textured surface, improves the retention of proteins on the surface, and encourages bone in-growth.

Abstract: Compositions and methods are provided for preparing a metal substrate having a uniform textured surface with a plurality of indentations with a diameter in the nanometer and micrometer range. The textured surface is produced by exposing the substrate to an etching fluid comprising a hydrogen halide acid and/or an oxyacid, a chloride containing compound, and an oxidizing agent. The etching solution can be used at ambient temperature without damaging the metal elements on the substrate surface. This textured surface enhances adherence of coatings or cells onto the textured surface, improves the retention of proteins on the surface, and encourages bone in-growth.

Abstract: Compositions and methods are provided for preparing a metal substrate having a uniform textured surface with a plurality of indentations with a diameter in the nanometer and micrometer range. The textured surface is produced by exposing the substrate to an etching fluid comprising a hydrohalic acid and a mixture of a hydrohalic acid and an oxyacid, a chloride containing compound, and an oxidant. The etching solution can be used at ambient temperature. This textured surface enhances adherence of coatings or cells onto the textured surface, improves the retention of proteins on the surface, and encourages bone in-growth.