Abstract:
IMPROVED TABULAR GRAIN EMULSIONS CONTAINING LAMINAR HALIDE STRATA Photographic emulsions are disclosed comprised of radiation sensitive silver iodobromide grains, at least 50 percent of the total projected area of said silver iodobromide grains being accounted for by tabular grains exhibiting a mean tabularity of greater than 5, at least 10 percent of which are comprised of two opposed parallel major crystal faces, a host stratum having an iodide content of at least 4 mole percent, and laminar strata containing less than 2 mole percent iodide interposed between said host stratum and said opposed major crystal faces. The emulsions are characterized in that each of the laminar strata is comprised of a surface layer forming one of the major surfaces and having a thickness in the range of from 20 to 350 .ANG. and a subsurface layer located immediately beneath and in contact with the surface layer containing a hexacoordination complex of a Group VIII period 4 or 5 metal and at least three cyanide ligands.
Abstract:
A heat transfer is disclosed which is primarily intended for application of designs to textiles. The transfer comprises a flexible carrier sheet bearing a transfer layer of a polymer composition which is rendered non-blocking at normal room temperatures by a pariculate solid dispersed therein. The particulate solid is selected so that at the melting temperature of the layer it is either removed completely by sublimation or is converted to a form which does not interfere with liquid phase transfer of the design to the textile.
Abstract:
A method for forming a structured doped cerium oxide nanoparticle including the steps of forming a first aqueous cerium(lll) reaction mixture, with optional metal/s other than cerium, a base, and a stabilizer; introducing an oxidant to singly oxidize cerium (III), followed by thermal formation of a doped cerium oxide nanoparticle core; then providing a second reaction mixture of one or more metal ions other than cerium, and optionally cerium (III) ions and sufficient cerium (III) oxidant, followed by thermally converting the mixture into a shell around the doped cerium oxide nanoparticle core, wherein the ratio of metal ions in the core differs from the ratio of metal ions in the shell. The disclosed structured doped cerium oxide nanoparticle may exhibit cubic fluorite crystal structure and possess a diameter in the range 1 nm-20 nm. A dispersion of the developed nanoparticle may be used as a fuel additive.
Abstract:
A method of making cerium dioxide nanoparticles includes: a) providing an aqueous reaction mixture having a source of cerous ion, a source of hydroxide ion, a nanoparticle stabilizer, and an oxidant at an initial temperature no higher than about 2O°C; b) mechanically shearing the mixture and causing it to pass through a perforated screen, thereby forming a suspension of cerium hydroxide nanoparticles; and c) raising the initial temperature to achieve oxidation of cerous ion to eerie ion and thereby form cerium dioxide nanoparticles having a mean diameter in the range of about 1 nm to about 15 nm. The cerium dioxide nanoparticles may be formed in a continuous process.
Abstract:
A lubricity additive composition includes a lubricating medium and, dispersed therein, cerium dioxide nanoparticles having a mean diameter of about 1 nm to about 15 nm. In a method for reducing friction between, or scarring, abrasion, or pitting of metal surfaces in relative motion with one another, at least one of the metal surfaces has been contacted with a lubricity additive composition that includes a lubricating medium and, dispersed therein, cerium dioxide nanoparticles whose mean diameter is about 1 nm to about 15 nm.
Abstract:
A process for making cerium-containing oxide nanoparticles includes providing an aqueous reaction mixture containing a source of cerous ion, optionally a source of one or more metal ions (M) other than cerium, a source of hydroxide ion, at least one monoether carboxylic acid nanoparticle stabilizer wherein the molar ratio of said monoether carboxylic acid nanoparticle stabilizers to total metal ions is greater than 0.2, and an oxidant at an initial temperature in the range of about 20°C to about 95°C. Temperature conditions are provided effective to enable oxidation of cerous ion to ceric ion, thereby forming a product dispersion of cerium-containing oxide nanoparticles, optionally containing one or more metal ions (M), Ce1-xMxO2-d, wherein "x" has a value from about 0.0 to about 0.95. The nanoparticles may have a mean hydrodynamic diameter from about 1 nm to about 50 nm, and a geometric diameter of less than about 45 nm.
Abstract:
A method of making cerium dioxide nanoparticles includes: a) providing an aqueous reaction mixture having a source of cerous ion, a source of hydroxide ion, a nanoparticle stabilizer, and an oxidant at an initial temperature no higher than about 2O°C; b) mechanically shearing the mixture and causing it to pass through a perforated screen, thereby forming a suspension of cerium hydroxide nanoparticles; and c) raising the initial temperature to achieve oxidation of cerous ion to eerie ion and thereby form cerium dioxide nanoparticles having a mean diameter in the range of about 1 nm to about 15 nm. The cerium dioxide nanoparticles may be formed in a continuous process.
Abstract:
A lubricity additive composition includes a lubricating medium and, dispersed therein, cerium dioxide nanoparticles having a mean hydrodynamic diameter of about 1 nm to about 15 nm. In a method for reducing friction between, or scarring, abrasion, or pitting of metal surfaces in relative motion with one another, at least one of the metal surfaces has been contacted with a lubricity additive composition that includes a lubricating medium and, dispersed therein, cerium dioxide nanoparticles whose mean hydrodynamic diameter is about 1 nm to about 15 nm.