Abstract:
The invention discloses an anisotropic bonded magnetic powder and a preparation method thereof. The anisotropic bonded magnetic powder has a general formula of R1R2TB, wherein R1 is a rare earth element containing Nd or PrNd, R2 is one or two of La and Ce, T is a transitional element, and B is boron. The preparation method includes the steps of smelting the master alloy to prepare ingot(s), preparing a rare earth hydride of formula R1TBHX, preparing a hydride diffusion source of formula R1R2THX, mixing, heat treating, and high-vacuum dehydrogenating, to obtain the anisotropic bonded magnetic powder. The invention uses La and Ce hydrides as the diffusion source, can save cost, remove hydrogen from the diffusion source at a lower dehydrogenation temperature, avoid crystal grain growth at a high temperature, and ensure the quality of the product.
Abstract:
Phosphor, a preparation method for the phosphor, and a light emitting device having the phosphor. The phosphor comprises an inorganic compound which at least comprises an element M, an element A, an element D, and an element R; the element M is one or two elements selected from the group consisting of Lu, La, Pr, Nd, Sm, Y, Tb, and Gd and must comprise Lu; the element A is Si and/or Ge; the element D is one or two elements selected from the group consisting of O, N, and F and must comprise N; the element R is Ce and/or Dy. Since the ionic radius of Lu3+ is smaller than that of La3+, when the inorganic compound comprises element Lu, the original ligand site would be contracted. In order to reduce lattice distortion due to the ligand site contraction, the adjacent ligand site expands, and the photochromic property is adjusted.
Abstract:
Provided are a cerium-zirconium composite oxide, a preparation method therefor and application of a catalyst. The cerium-zirconium composite oxide has a composite phase structure, and comprises a cerium oxide phase and a cerium-zirconium solid solution phase, or consists of two or more cerium-zirconium solid solution phases with different crystal structures and different chemical compositions, wherein the chemical formula of the cerium-zirconium solid solution phase is CexZr1-x-yMyO2, where M is at least one selected from the group consisting of a rare earth element other than cerium, a transition metal element and an alkaline earth metal element, x is 15-85 mol %, and y is 0-20 mol %.
Abstract:
A method for comprehensively recovering rare earth elements and fluorine element in a bastnaesite treatment process. The method comprises: oxidation roasting a bastnaesite, and leaching a roasted mixture using a hydrochloric acid, adding a roasting promoter to the bastnaesite during the roasting process; and/or during the leaching process using the hydrochloric acid, adding a catalytic leaching promoter into the mixture, obtaining a rare earth chloride solution containing little cerium element and a cerium-rich residue containing the fluorine element; and separating and recovering rare earth fluorides from the cerium-rich residue.
Abstract:
A method for comprehensively recovering rare earth elements and fluorine element in a bastnaesite treatment process. The method comprises: oxidation roasting a bastnaesite, and leaching a roasted mixture using a hydrochloric acid, adding a roasting promoter to the bastnaesite during the roasting process; and/or during the leaching process using the hydrochloric acid, adding a catalytic leaching promoter into the mixture, obtaining a rare earth chloride solution containing little cerium element and a cerium-rich residue containing the fluorine element; and separating and recovering rare earth fluorides from the cerium-rich residue.
Abstract:
The present invention provides a cerium oxide based composite polishing powder and a preparation method thereof. The polishing powder contains the element magnesium in an amount of 0.005 wt %-5 wt % to magnesium oxide meter. The preparation method includes: (1) uniformly mixing a salt solution containing cerium serving as the main component of the polishing powder; (2) uniformly mixing a precipitating agent of an aqueous magnesium bicarbonate solution with the mixed solution prepared in step (1) to obtain a slurry; (3) aging the slurry prepared in step (2) for 0-48 h while the temperature of the slurry is kept at 30-90 degrees centigrade, and filtering the aged slurry to obtain the precursor powder of the polishing powder; (4) calcinating the precursor powder at 600-1000 degrees centigrade, then dispersing and separating the calcinated precursor powder to obtain the polishing powder. The present invention improves the polishing performance and the suspension performance of polishing powder.
Abstract:
Disclosed are an organic slurry for neodymium iron boron screen printing and a preparation method. The organic slurry includes a rare earth powder, an organic solvent, a resin, a dispersant, and/or a leveling agent, weight percentages of which are as follows: rare earth powder 50%-90%; organic solvent 8%-50%; resin 0.4%-6%; dispersant 0%-5%; and leveling agent 0%-3%. The preparation method includes: sequentially adding the weighed organic solvent, resin, dispersant, and/or leveling agent into a mixer, stirring at a constant temperature, and then cooling to room temperature to obtain an organic carrier; adding the organic carrier and the weighed rare earth powder into a vacuum high-speed disperser, and dispersing at a high speed to obtain a crude organic slurry; and transferring the crude organic slurry to a gap adjustable three-roll grinder, and grinding to obtain a fine organic slurry.
Abstract:
The present invention discloses an yttrium-added rare earth permanent magnet material and a preparation method therefor. The chemical formula of the material is expressed as (YxRe1-x)aFe100-a-b-cMbBc according to the mass percentage, wherein 0.05≤x≤0.5, 20≤a≤28, 0.5≤b≤2, 0.5≤c≤1.5, Re is Nd and/or Pr, and M is Al and/or Nb. According to the present invention, the relatively surplus and inexpensive rare earths yttrium and cerium are used to replace Nd and/or Pr in NdFeB. By controlling the ratio of the rare earth elements such as yttrium, cerium and neodymium, and adding an appropriate amount of Nb and/or Al element, the rare earth elements are used in a comprehensive and balanced manner while better magnetic properties are maintained.
Abstract:
An optical device includes an LED chip, a light absorber and/or visible-light luminescent material, and a near-infrared luminescent material, wherein a luminous power of light emitted by the near-infrared luminescent material and the light absorber and/or visible-light luminescent material in a band of 650-1000 nm under the excitation of the LED chip is A, and a sum of a luminous power of light emitted by the near-infrared and visible-light luminescent materials in a band of 350-650 nm under the excitation of the LED chip and a luminous power of residual light emitted by the LED chip in the band of 350-650 nm after the LED chip excites the near-infrared and visible-light luminescent materials is B, with B/A*100% being 0.1%-10%. According to the implementation where the optical device employs the LED chip to combine the near-infrared luminescent material and the light absorber and/or visible-light luminescent material simultaneously.
Abstract:
The present invention discloses a red light and near-infrared light-emitting material and a light-emitting device. The red light and near-infrared light-emitting material contains a compound represented by a molecular formula, xA2O3·yIn2O3·bR2O3, wherein the element A is Sc and/or Ga; the element R is one or two of Cr, Yb, Nd or Er and necessarily includes Cr; and 0.001≤x≤1, 0.001≤y≤1, 0.001≤b≤0.2, and 0.001≤b/(x+y)≤0.2. The light-emitting material can be excited by a technically mature blue light source to emit light with a high-intensity wide-spectrum or multiple spectra. Compared with existing materials, the light-emitting material has higher luminescent intensity. The light-emitting device uses an LED chip to combine an infrared light-emitting material and a visible light light-emitting material. In this way, the same LED chip can emit near-infrared light and visible light at the same time, which greatly simplifies the packaging process and reduces the packaging cost.