605 results about "Niobium pentoxide" patented technology

A niobium suboxide powder comprising 100 to 600 ppm of magnesium is described. The niobium suboxide powder may (alternatively or in addition to 100 to 600 ppm of magnesium) further include 50 to 400 ppm of molybdenum and/or tungsten. The niobium suboxide powder is suitable for the production of: capacitors having an insulator layer of niobium pentoxide; capacitor anodes produced from the niobium suboxide powder; and corresponding capacitors.

The present invention relates to novel lubricant additives for improving the tribological properties, novel lubricants containing these additives, processes for the preparation thereof and the use thereof. Lubricant comprises ceramic nanoparticles as additives comprising aluminum oxide, aluminum nitride, silicon dioxide, titanium dioxide, zirconium oxide, yttrium oxide, tungsten oxide, tantalum pentoxide, vanadium pentoxide, niobium pentoxide, cerium dioxide, boron carbide, aluminum titanate, boron nitride, molybdenum disilicide, silicon carbide, silicon nitride, titanium carbide, titanium nitride, zirconium diboride and/or clay minerals, and thermally stable carbonates and/or sulfates. The nanoparticles represent an ellipsoid with three semi-axes a, b and c, which are not equal to each other, or equal to each other. The ratio of a and b is 1-100, a and c is 1-1000, and b and c is 1:100.

The invention discloses a wearing-resistant high-hardness ceramic glaze and a preparation method thereof and relates to the technical field of ceramic glazes. The wearing-resistant high-hardness ceramic glaze comprises the following raw materials: albite, potassium feldspar, kaolin, quartz sand, zinc white, high-aluminum clay, calcite, talc, lithium porcelain, cordierite, zirconium sand, mullite powder, wollastonite, boron carbide, niobium pentoxide, zinc oxide and frit. Both the Vickers hardness and the wearing resistance of a full polish glaze brick made of the glaze disclosed by the invention can be improved, and market requirements on full polish glaze bricks with high hardness and wearing resistance can be met; when a glaze surface is sintered, a great number of bubbles are not generated, and the product is good in antifouling performance and high in glossiness after polishing; expansion coefficients of the full polish brick and a glaze layer are approximate to those of a porcelain blank, the glaze layer is subjected to small inner stress, polishing omission or partial exposure phenomena can be avoided in polishing, and thus product quality can be ensured.

A bonding layer 3 is formed over a piezoelectric material substrate, and the bonding layer 3 is made of or more material selected from the group consisting of silicon nitride, aluminum nitride, alumina, tantalum pentoxide, mullite, niobium pentoxide and titanium oxide. Neutralized beam A is irradiated onto a surface 4 of the bonding layer and a surface of a supporting body to activate the surface of the bonding layer and the surface of the supporting body. The surface of the bonding layer and the surface of the supporting body are bonded by direct bonding.

The invention discloses high-refractive-index ultraviolet-transparent glass and a manufacturing method thereof. The high-refractive-index ultraviolet-transparent glass comprises following components, by weight, 5-15% of SiO2, 10-25% of B2O3, 0-5% of CaO, 0-5% of SrO, 10-50% of BaO, 10-50% of La2O3, 5-15% of Nb2O5, 0-5% of Y2O3, 0-5% of ZrO2 and 0-5% of TiO2. The invention also provides the manufacturing method of the high-refractive-index ultraviolet-transparent glass. The method includes following steps: placing quartz sand, boronic acid or boron anhydrous, calcium carbonate, strontium carbonate, barium carbonate, lanthanum oxide, niobium pentoxide, yttria, zirconium oxide and titanium dioxide according to requirement in a formula into a pure-platinum crucible with addition of a reduction agent, melting the materials at 1400-1600 DEG C for 6-10 hours with stirring for 2-3 times during the melting process, and casting the molten glass into a specified specification. The invention also discloses an application of the high-refractive-index ultraviolet-transparent glass in an ultraviolet-transparent optical fiber plate. The high-refractive-index ultraviolet-transparent glass is high in refractive index and transmittance and is good in chemical stability.

The invention relates to a process for producing capacitors based on niobium suboxide, and having an insulator layer of niobium pentoxide. Also described is a powder mixture suitable for production of capacitors. Pressed bodies produced from the powder mixture, and capacitors having specific properties are also disclosed.

The invention relates to a preparation method of a niobium (V) pentoxide urchin-like nano sphere and an application of the nano sphere as a photocatalyst. The preparation method comprises the following steps: step one, weighing alcohol and deionized water according to a volume ratio of 20:1 to 1:100 at a room temperature, mixing water and alcohol, and stirring to prepare an alcohol solution; step two, weighing soluble niobium salt, dissolving the soluble niobium salt into the alcohol solution obtained in the step one, and stirring for 0.5 to 5 hours to obtain a transparent solution; step three, transferring the obtained transparent solution to a hydrothermal reactor, wherein the transparent solution accounts for 50 to 70% of the total volume of the reactor, and the hydrothermal reactions are performed at a temperature of 100 to 220 DEG C, after reactions, naturally cooling the reactor to the room temperature, and washing and drying the reaction products to obtain the niobium (V) pentoxide urchin-like nano spheres. According to the preparation method, alcohol is used to adjust the polarity of the solution so as to adjust the growth speed of niobium, and thus niobium (V) pentoxide urchin-like nano spheres, which have uniform morphology and controllable diameters, are obtained. The prepared niobium (V) pentoxide urchin-like nano spheres has a high catalytic activity on degrading dyes in water in the presence of visible light.

The invention relates to a conductive niobium oxide target and a preparation method and application thereof. The niobium oxide target consists of NbOx, wherein x is more than 0.05 and less than 2.5, and according to the Archimedes method, the relative density of the niobium oxide target is not lower than 99 weight percent, the crystal structure is of a cubic crystal shape, the tensile strength is 10-20MPa, the Young's modulus is 1500-2800MPa and the resistivity is 0.03-1Omega.cm. The average transmittance of the film prepared with the conductive niobium oxide target is more than 94 percent within the visible spectral range. The preparation method comprises the following steps: mixing niobium pentoxide powder and niobium powder; filling the mixture into a die, placing the die into a sintering furnace, and carrying out pressure sintering in the inert or vacuum environment; and maintaining the temperature for 8-15 hours under the constant temperature and the constant pressure, and releasing the pressure, thereby obtaining the niobium oxide target. The invention has the advantages that the prepared niobium oxide target has excellent electrical conductivity, and the film with a high refractive index can be prepared through DC sputtering and intermediate-frequency sputtering.

The invention relates to a hydrothermal synthesis method for preparation of sodium-potassium niobate lead-free piezoelectric ceramic powder intermingled with tantalum, which belongs to the functional ceramic material field. The invention is characterized in that sodium hydroxide, potassium hydroxide, niobium pentaoxide and tantalum pentoxide are used as raw materials at the temperature ranging from 200 to 250 DEG C, and K0.5Na0.5NbO3 piezoelectric ceramic powder intermingled with Ta can be achieved by hydrothermal synthesis while preserving the heat for 20 to 36 hours; the molar ratio of the total added amount of niobium pentaoxide and tantalum pentoxide to alkali solution is 1:10 to 1:25, and the molar ratio of the added niobium pentaoxide to tantalum pentoxide is 1:9 to 4:6; the solution mixture ratio of sodium hydroxide to potassium hydroxide is 1:4 to 1:6, and the concentration of alkali solution is 4-10mol/L. The synthesis temperature is low and the powder grain is fine and average with a diameter about hundreds of nanometers in the invention. And the surface activity is great, which is favorable to the ceramic sintering at the latter stage.

The invention discloses a Mn-Zn ferrite magnetic material, a magnetic core and a related manufacturing method. The primary composition of Mn-Zn soft magnetic ferrite materials: 49.5 to 53.9 mol percentages of iron oxide Fe2O3, 34.6 to 39.8 mol percentages of manganese oxide MnO, and 8.5 to 13.8 percentages of zinc oxide ZnO. Furthermore, a first assistant component with a weight of 100 to 600ppm, as well as a second assistant component with a weight of 50 to 3000ppm are added into the primary composition; wherein the first assistant component refers to one or more materials as silicon dioxide SiO2 or tantalum oxide Ta2O5; the second assistant component refers to one or more materials as bismuth trioxide Bi2O3, niobium pentoxide Nb2O5 or \ tungsten trioxide WO3. A magnetic billet can be prepared according the formula, followed by high temperature sintering under 1280 to 1360 DEG C in a nitrogen-protected kiln. The manufactured magnetic core has the advantages of high anti-DC-superposing performance and lower power consumption.

The invention discloses a photocatalytic hydrogen production catalyst and a preparation method thereof. The catalyst is molybdenum disulfide composite carbon-doped potassium niobate, the chemical composition formula of the catalyst is xMoS2/C-KNbO3, x refers to the molar ratio of molybdenum disulfide to potassium niobate, C-KNbO3 refers to carbon-doped potassium niobate, and 0.001<=x<=0.01. Firstly, niobium pentoxide, glucose and potassium hydroxide are used for preparing the carbon-doped potassium niobate. Secondly, the carbon-doped potassium niobate, sodium molybdate and thiourea are used for preparing the molybdenum disulfide composite carbon-doped potassium niobate. The catalyst has efficient photocatalytic hydrogen production performance and good stability.

The invention discloses a preparation method of a carbon and nitrogen doped niobium (V) pentoxide nano sheet and an application of the nano sheet as a photocatalyst. The preparation method comprises the following steps: weighing soluble niobium salt at a room temperature, adding anhydrous ethanol to form an ethanol solution of niobium salt, dropwise adding an organic ammonium hydroxide solution into the ethanol solution of niobium salt, wherein in the initial phase, white turbidity appears, keeping on adding the organic ammonium hydroxide solution until the white turbidity disappears so as to form a clear and transparent solution; transferring the obtained solution to a hydrothermal reactor, wherein the solution accounts for 50 to 70% of the volume of the hydrothermal reactor, carrying out hydrothermal reactions at a temperature of 100 to 280 DEG C, after reactions, naturally cooling the reactor to the room temperature, washing and drying the reaction product to obtain white powder; and burning the white powder for 2 to 12 hours at a temperature of 400 to 1200 under the protection of nitrogen gas so as to obtain the carbon and nitrogen doped niobium (V) pentoxide nano sheet. The invention also discloses an application of the carbon and nitrogen doped niobium (V) pentoxide nano sheet as a photocatalyst. The photocatalyst can be applied to benzyl alcohol oxidation to prepare benzaldehyde.

A capacitor uses niobium pentoxide in the manufacture of a semiconductor device. The niobium pentoxide has a low crystallization temperature of 600° C. that provides control over the oxidation of the bottom electrode during heat-treatment. A dielectric constituent present as an amorphous oxide along the grain boundaries of polycrystalline niobium pentoxide is used for a capacitor insulator., thereby providing a method to decrease the leakage current along the grain boundary of niobium pentoxide and to realize a high dielectric constant and low-temperature crystallization.

The invention relates to a method for preparing tin niobate nanospheres by using alcohol solvent heat, and belongs to the field of functional materials. The method comprises the following steps: mixing SnCl2.2H2O and niobium pentoxide (Nb2O5) powder, concocting a pasty material, adding an organic alcohol (such as ethanol, isopropanol, ethylene glycol and glycerol) and a surfactant polyvinylpyrrolidone (PVP), and performing alcohol heat treatment on the above mixture to obtain the thermodynamically-metastable SnNb2O6 nanosphere material. The obtained SnNb2O6 nanospheres have better applicationprospects in the field of photocatalysis.

The invention relates to a method for preparing potassium niobate nano powder. The single-phase nano KNbO3 powder can be obtained at a low temperature by the method. The method comprises the following steps of: mixing potassium hydroxide and niobium pentaoxide in a molar ratio of 8-12:1, calcining the mixture for 1 to 4 hours at the temperature of between 320 and 400 DEG C, dissolving the obtained solid into deionized water, adding oxalic acid, regulating the pH value of the solution to between 4 and 5, and obtaining white sediment; dissolving the white sediment into aqueous solution of citric acid, adding potassium nitrate according to the component proportion of KNbO3, and obtaining a precursor by sol-gel and burning processes; and calcining the precursor at the temperature of between 600 and 800 DEG C to obtain the potassium niobate powder with grain diameter of between 10 and 70 nanometers and with perovskite structure. The process is simple and quick, the prepared powder has high purity and low granularity, and the cost is reduced.