摘要:
A composite oxide with a high oxygen storage capacity is provided without using cerium. The composite oxide is an iron oxide-zirconia composite oxide containing iron, zirconium, and a rare-earth element. The total content of Fe2O3, ZrO2, and an oxide of the rare-earth element is not less than 90 mass %, the content of an iron oxide in terms of Fe2O3 is 10 to 90 mass %, and the absolute value of the covariance COV(Fe, Zr+X) of the composite oxide, which has been baked in the atmosphere at a temperature of greater than or equal to 900° C. for 5 hours or more, is not greater than 20.
摘要:
A process for making cerium-containing oxide nanoparticles includes providing an aqueous reaction mixture containing a source of cerous ion, a source of hydroxide ion, at least one monoether carboxylic acid wherein the molar ratio of said monoether carboxylic acid to cerous ions is greater than 0.2, and an oxidant. The cerous ion is oxidized to ceric ion, thereby forming a product dispersion of cerium-containing oxide nanoparticles CeO2-δ, wherein δ has a value of about 0.0 to about 0.5.
摘要:
A single-crystalline LnBM2O5+δ or LnBM2O5.5+δ compound is provided, which includes an ordered oxygen vacancy structure; wherein Ln is a lanthanide, B is an alkali earth metal, M is a transition metal, O is oxygen, and 0≦δ≦1. Methods of making and using the compound, and devices and compositions including same are also provided.
摘要:
A light-transmitting bismuth-substituted rare-earth iron garnet-type calcined body expressed by R3−xBixYe5O12 and having an average crystal particle diameter of 0.3-10 micrometers, and a magneto-optical device using said calcined body; wherein R is at least one kind of elements selected from a group consisting of Y and lanthanoids, and x is a number from 0.5 to 2.5.
摘要:
Catalyst system suitable especially for the removal of CO compounds, comprising or consisting of an oxide, preferably of fluorite crystalline structure, conforming to the following molar formulation: Ce1−uMyAzDvO2−x, wherein Ce is cerium, A represents at least one element possessing a plurality of oxidation states and selected from Ti, Ga, In, V, Cr, Mn, Fe, Sn, Co, Ni, Cu, M represents at least one element selected from Gd, Y, Sc, Sm, Nd, Pr, Zn, D represents at least one element other than A and selected from Pt, Pd, Rh, Ru, Cu, Fe, Ag, and Au, u is between 0.05 and 0.45, y is between 0.01 and 0.4, Z is greater than 0 and less than 0.4, v is between 0.001 and 0.4, and x is greater than 0.
摘要:
A composition is described that includes a perovskite of the formula LaMO3, where M is at least one element selected from among iron, aluminum or manganese, in the form of particles dispersed on an alumina or aluminum oxyhydroxide substrate, wherein after calcination at 700° C. for 4 hours, the perovskite is in the form of a pure crystallographic phase, and in that the size of the perovskite particles does not exceed 15 nm. The described composition can be used in the field of catalysis.
摘要:
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-δ, 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.
摘要:
The thermoelectric conversion efficiency of a thermoelectric conversion device is increased by increasing the figure of merit of a spin-Seebeck effect element. An inverse spin-Hall effect material is provided to at least one end of a thermal spin-wave spin current generating material made of a magnetic dielectric material so that a thermal spin-wave spin current is converted to generate a voltage in the above described inverse spin-Hall effect material when there is a temperature gradient in the above described thermal spin-wave spin current generating material and a magnetic field is applied using a magnetic field applying means.
摘要:
A method of making cerium-containing metal oxide nanoparticles in non-polar solvent eliminates the need for solvent shifting steps. The direct synthesis method involves: (a) forming a reaction mixture of a source of cerous ion and a carboxylic acid, and optionally, a hydrocarbon solvent; and optionally further comprises a non-cerous metal ion; (b) heating the reaction mixture to oxidize cerous ion to ceric ion; and (c) recovering a nanoparticle of either cerium oxide or a mixed metal oxide comprising cerium. The cerium-containing oxide nanoparticles thus obtained have cubic fluorite crystal structure and a geometric diameter in the range of about 1 nanometer to about 20 nanometers. Dispersions of cerium-containing oxide nanoparticles prepared by this method can be used as a component of a fuel or lubricant additive.
摘要:
A sintered ferrite magnet comprising (a) a ferrite phase having a hexagonal M-type magnetoplumbite structure comprising Ca, an element R which is at least one of rare earth elements and indispensably includes La, an element A which is Ba and/or Sr, Fe, and Co as indispensable elements, the composition of metal elements of Ca, R, A, Fe and Co being represented by the general formula of Ca1-x-yRxAyFe2n-zCoz, wherein the atomic ratios (1-x-y), x, y and z of these elements and the molar ratio n meet the relations of 0.3≦(1-x-y)≦0.65, 0.2≦x≦0.65, 0≦y≦0.2, 0.03≦z≦0.65, and 4≦n≦7, and (b) a grain boundary phase indispensably containing Si, the amount of Si being more than 1% by mass and 1.8% or less by mass (calculated as SiO2) based on the entire sintered ferrite magnet, and its production method.