10 results about "Cerium fluoride" patented technology

The embodiment of the invention provides a friction material composition, a brake lining, a preparation method of the brake lining, a brake and a vehicle. The friction material composition comprises the following raw materials in parts by weight: 2-10 parts of a fluoride mixture, 8-15 parts of graphite, 8-12 parts of phenolic resin, 4-12 parts of a metal oxide, 15-40 parts of a fiber material and 20-40 parts of other fillers, wherein the fluoride mixture comprises at least two of calcium fluoride, barium fluoride, cerium fluoride, aluminum fluoride, magnesium fluoride, potassium fluoride, sodium fluoride, beryllium fluoride and manganese fluoride. The brake lining prepared from the friction material composition can solve the problems of high wear rate and heat fading at the same time, the service life of the brake lining is prolonged, and the braking effect is improved.

The invention discloses a method for separating and recovering fluorine from a waste acid solution, which comprises the following steps: S1, taking a solution to be treated, and adding an extracting agent for extraction to obtain an organic phase and a water phase; the extraction agent is an N235 extraction agent; and S2, adding a cerium (III) salt solution into the organic phase as a stripping agent, layering, and recovering cerium fluoride precipitate in the stripping solution. According to the scheme, cerium salt is adopted as a stripping agent, and fluorine is separated out in a water-insoluble cerium fluoride precipitation form by utilizing the strong coordination effect between Ce < 3 + > and F <->, so that fluorine in an organic phase is directly converted into a high-purity cerium fluoride product. The method breaks through the limitation that only fluorine is separated and direct recycling is difficult in a traditional reverse extraction process, and one-step method recycling of fluorine is achieved. And the organic phase after reverse extraction can be directly regenerated and recycled, so that the medicament consumption is reduced, and the economical efficiency of the process is also improved.

The application belongs to the technical field of fuel cells, and discloses a porous cerium fluoride catalyst, a preparation method and application thereof. The application adopts an impregnation method to synthesize a composite oxide precursor with silica as a template, obtains the composite oxide after calcination, and then adopts hydrofluoric acid etching and fluorination to prepare cerium fluoride. Finally, the porous cerium fluoride, a carrier, a platinum source aqueous solution and an alcohol solution are mixed to perform a hydrothermal reaction, and the porous cerium fluoride catalyst is obtained. The application etches away the template skeleton by using hydrofluoric acid to form a porous structure. The pore diameter of the cerium fluoride carrier is controlled by adjusting the concentration of the hydrofluoric acid, the specific surface area of the catalyst carrier is increased, more active sites are provided for the adsorption of platinum nanoparticles, the proton transmission speed is accelerated, the amount of noble metal is reduced, and the catalyst activity is improved.

The invention provides a high-chromium cast iron surfacing flux-cored wire for a shield tunneling machine and a preparation method of the high-chromium cast iron surfacing flux-cored wire. The high-chromium cast iron surfacing flux-cored wire is formed by wrapping powder with a steel belt, and the powder accounts for 33.0%-36.0% of the total weight of the flux-cored wire; the powder comprises, by mass, 3%-8% of reduced iron powder, 1%-3% of fluorite, 0.5%-1% of rare earth fluoride, 3%-8% of electrolytic manganese, 1%-5% of high silicon iron, 80%-85% of ferrochrome carbide, 5%-9% of graphite and 1%-3% of nickel powder. Wherein the rare earth fluoride is cerium fluoride. The high-chromium cast iron surfacing flux-cored wire for the shield tunneling machine is excellent in welding process, stable in electric arc, small in splashing, attractive in forming and capable of conducting all-position welding.

The application relates to the technical field of magnets, in particular to a cerium-doped high-coercivity neodymium-iron-boron magnet and a preparation process thereof. In view of the problem that the existing cerium-doped magnet has insufficient coercivity and reduced remanence due to uneven distribution of cerium, the process comprises the following steps: fluorination treatment on the surface of a main phase powder, cold pressure forming in a magnetic field, electrophoretic deposition to build a cerium fluoride skeleton, step-by-step vacuum impregnation of cerium salt and a fluorine source, and degreasing, sintering and grain boundary heat treatment. The method controls the uniform enrichment of cerium at the grain boundary, forms a continuous and dense grain boundary phase, effectively improves the intrinsic coercivity, remanence and high-temperature stability, simultaneously improves the corrosion resistance and reduces the dependence on heavy rare earths.

A solid-state imaging device according to an embodiment includes: a semiconductor substrate including a photoelectric conversion element; a lens disposed above a first light incident surface of the photoelectric conversion element; and a plurality of columnar structures disposed on a surface parallel to the first light incident surface that is located between a second light incident surface of the lens and the first light incident surface of the photoelectric conversion element. The columnar structure includes at least one of silicon, germanium, gallium phosphide, aluminum oxide, cerium oxide, hafnium oxide, indium oxide, tin oxide, niobium pentoxide, magnesium oxide, tantalum pentoxide, titanium pentoxide, titanium oxide, tungsten oxide, yttrium oxide, zinc oxide, zirconia, cerium fluoride, gadolinium fluoride, lanthanum fluoride, and neodymium fluoride.

The application discloses a welding rod for 1000MPa high-strength steel and a preparation method thereof. The welding rod comprises a coating and a welding core, and the coating is wrapped on the outside of the welding core. The coating powder comprises the following components in parts by weight: 30-35 parts of fluorite, 20-30 parts of dolomite, 5-8 parts of strontium carbonate, 2-5 parts of sodium titanium silicate, 5-10 parts of potassium oxalate, 5-10 parts of atomized ferrosilicon, 2-5 parts of titanium powder, 0.5-1.0 parts of lanthanum cerium fluoride, 1-5 parts of lithium carbonate, 1-2 parts of sodium carboxymethyl starch, 0.5-1.5 parts of copper powder and 8-15 parts of iron powder. The welding rod has excellent all-position welding process performance, the arc is stable during welding, fine droplet transition is presented, the molten slag has moderate fluidity, the welding spatter is small, and the weld formation is fine and beautiful.

The utility model provides a tail gas treatment device in praseodymium-neodymium metal production. The tail gas treatment device comprises an electrolysis workshop, an induced draft fan, a first absorption tower, a second absorption tower and a third absorption tower which are sequentially connected in series, the first absorption tower and the second absorption tower are respectively connected with the acid water treatment device to form a loop, the first absorption tower and the second absorption tower are also respectively connected with the clear water storage tank, and the acid water treatment device is also connected with the cerous carbonate solution storage tank; the third absorption tower is also connected with an alkali absorption liquid treatment device to form a loop. According to the scheme, the equipment is used in cooperation, fluorine in the electrolytic tail gas is converted into cerium fluoride with high recovery value to achieve recovery of fluorine resources, residual fluorine is treated through the alkaline calcium solution to achieve defluorination of the electrolytic tail gas, and the defect that the fluorine resources in the electrolytic tail gas in existing praseodymium-neodymium metal treatment production cannot be fully utilized is overcome.

The invention relates to the technical field of magnets, in particular to a cerium-doped high-coercivity neodymium-iron-boron magnet and a preparation process thereof. In order to solve the problems of insufficient coercive force and reduced residual magnetism caused by non-uniform cerium distribution of the existing cerium-doped magnet, the process comprises the following steps: main phase powder surface fluorination treatment, magnetic field orientation cold press molding, construction of a cerium fluoride skeleton by electrophoretic deposition, step-by-step vacuum impregnation of cerium salt and a fluorine source, and degreasing sintering and grain boundary heat treatment. According to the method, uniform enrichment of cerium at the grain boundary is controlled, a continuous and compact grain boundary phase is formed, the intrinsic coercive force, residual magnetism and high-temperature stability are effectively improved, meanwhile, corrosion resistance is improved, and dependence on heavy rare earth is reduced.

A solid-state imaging device according to an embodiment includes: a semiconductor substrate including a photoelectric conversion element; a lens disposed above a first light incident surface of the photoelectric conversion element; and a plurality of columnar structures disposed on a surface parallel to the first light incident surface that is located between a second light incident surface of the lens and the first light incident surface of the photoelectric conversion element. The columnar structure includes at least one of silicon, germanium, gallium phosphide, aluminum oxide, cerium oxide, hafnium oxide, indium oxide, tin oxide, niobium pentoxide, magnesium oxide, tantalum pentoxide, titanium pentoxide, titanium oxide, tungsten oxide, yttrium oxide, zinc oxide, zirconia, cerium fluoride, gadolinium fluoride, lanthanum fluoride, and neodymium fluoride.