206 results about "Tetragonal crystal system" patented technology

A perovskite type oxide of a single crystal structure or a uniaxial-oriented crystal structure represented by

• • ABO₃ where site A includes Pb as a main component and site B includes a plurality of elements, wherein the perovskite type oxide includes a plurality of crystal phases selected from the group consisting of tetragonal, rhombohedral, orthorhombic, cubic, pseudo-cubic and monoclinic systems and the plurality of crystal phases are oriented in the direction of <100>.

An actuator device includes: a layer provided on a single crystal silicon (Si) substrate, and made of silicon dioxide (SiO₂); at least one buffer layer provided on the layer made of silicon dioxide (SiO₂); a base layer provided on the buffer layer, and made of lanthanum nickel oxide (LNO) having the (100) plane orientation; and a piezoelectric element. The piezoelectric element includes: a lower electrode provided on the base layer, and made of platinum (Pt) having the (100) plane orientation; a piezoelectric layer made of a ferroelectric layer whose plane orientation is the (100) orientation, the piezoelectric layer formed on the lower electrode by epitaxial growth where a crystal system of at least one kind selected from a group consisting of a tetragonal system, a monoclinic system and a rhombohedral system dominates the other crystal systems; and an upper electrode provided on the piezoelectric layer.

The invention relates to a compound potassium lead borophosphate nonlinear optical crystal as well as a preparation method and application thereof. The compound has the chemical formula of KPbBP2O8. The preparation method comprises the following steps of: after uniformly mixing a raw material containing K, Pb, B and P by adopting a solid-phase reaction method, heating for carrying out solid-phase reaction to obtain a compound of the potassium lead borophosphate; and growing a crystal on the compound by adopting a melt method to obtain the potassium lead borophosphate nonlinear optical crystal. The compound is the centimeter-grade large size nonlinear optical crystal of a tetragonal crystal system; a space group is I-42d; cell parameters comprise a=7.1764(7), b=7.1764(7), c=13.9483(13), Z=4 and V=718.35; the powder frequency doubling effect of the compound is equivalent to that of KDP (Potassium Dihydrogen Phosphate); the Mohs hardness is 4 to 5; and the potassium lead borophosphate nonlinear optical crystal has the advantages of easy cutting, polishing processing and storage, no deliquescence, high preparation speed, simple operation, low cost, good mechanical performance, difficult cracking, stable physicochemical property, and the like and is suitable for manufacturing an nonlinear optical device.

The solid acid catalyst for isomerizing C4-C7 alkane includes sulfate radical and VIII metal carried on carrier, and the carrier consists of zirconia, alumina and one kind of modifying element selected from RE element or IIA metal. The catalyst contains zirconia in tetragonal crystal system, S 0.5-5.0 wt%, VIII metal 0.1-5.0 wt% and modifying element 0.1-10.0 wt%, and has zirconia/alumina mass ratio of 10-90 to 10-90. The catalyst is used in isomerizing lower alkane and has high activity stability and isomerizing selectivity.

The invention relates to a preparation method of two-dimensional bismuth oxygen selenium atom crystals. The method comprises the following steps that a precursor containing bismuth elements and selenium elements is subjected to physical vapor deposition, a two-dimensional bismuth oxygen selenium atom crystal material is obtained, and the two-dimensional bismuth oxygen selenium atom crystal material is a tetragonal system. By adopting physical vapor deposition, the problem that the ratio of a bismuth source to a selenium source is not easily controlled in the chemical gas-phase reaction processis solved, the obtained two-dimensional bismuth oxygen selenium atom crystal material is higher in purity, vacancy defects are less, then, the electronic mobility is higher, the electronic mobility is larger than or equal to 135 cm<2>/(V s), meanwhile, compared with chemical vapor deposition, the physical vapor deposition can enable the crystal form integrity of the two-dimensional bismuth oxygenselenium atom crystal material to be higher, the crystal size is larger, the single crystal domain edge can reach the millimeter scale, the maximum single crystal domain edge is not smaller than 1.7mm, and the minimum signed crystal domain edge is not smaller than 200 micrometers.

The invention relates to a superfine rare earth magnesium silicate strontium fluorescent powder and a preparation technology thereof. The superfine rare earth magnesium silicate strontium fluorescent powder is characterized in that the fluorescent power takes Sr2MgSi2O7 as a matrix, and Eu<2+> and Dy<3+> rare earth ions as activating agents, a crystal structure is a tetragonal system akermanite structure, the grain size of the powder is less than 5mu m, and the powder can emit blue visible lights with the wavelength of about 470nm after irradiated by ultraviolet or visible lights for 1-10 minutes, and the afterglow service life of the powder reaches above 5 hours. The fluorescent powder is nontoxic, harmless and free of radioactive contamination and has no adverse effect on human bodies and the environment. The main preparation processes of the superfine fluorescent power are as follows: a rare earth magnesium silicate strontium precursor and xerogel are prepared through a sol-gel technology, and then a rare earth magnesium silicate luminescent material is obtained through high-temperature roasting, and the superfine fluorescent powder with the grain size of less than 5mu m is obtained by smashing and grinding the luminescent material.

The invention relates to the fields of inorganic luminescent nanomaterials and preparation thereof and particularly relates to a europium and dysprosium rare earth ion co-doped strontium magnesium silicate luminescent nanofiber and a preparation method thereof. The europium and dysprosium rare earth ion co-doped strontium magnesium silicate luminescent nanofiber is characterized by being of a continuous one-dimensional nanostructure, wherein Sr2MgSi2O7 is used as a substrate, Eu<2+> and Dy<3+> rare earth ions are used as activating agents, a crystal is of an akermanite structure of a tetragonal crystal system, and the europium and dysprosium rare earth ion co-doped strontium magnesium silicate luminescent nanofiber can emit blue visible light with the wavelength close to 470nm after being irradiated by ultraviolet rays or visible light for 1-10min. The luminescent nanofiber is used for preparing a precursor solution suitable for electrostatic spinning through a sol-gel technology, then, a precursor nanofiber is prepared through electrostatic spinning and is calcined at a weak reducing atmosphere, and finally, the Sr2MgSi2O7: Eu<2+> and Dy<3+> luminescent nanofiber is obtained.

The invention relates to an infrared non-linear optical material Ba3AGa5Se10Cl2 and a preparation method thereof. The infrared non-linear optical material Ba3AGa5Se10Cl2 is synthesized by a high-temperature solid phase synthesis method by reacting at the temperature of 850 DEG C for 100 hours. In the invention, a novel infrared non-linear optical crystal Ba3AGa5Se10Cl2 (A=Cs, Rb and K) belongs to a tetragonal system space group; Ba3CsGa5Se10Cl2 has high non-linear performance; during primary measurement, the particle size of the material of 2.05 micrometers is between 46 and 74 micrometers, and the non-linear coefficient of the material is 13.6 times that of a commercial material AgGaS2; and the material can have potential non-linear optical application value.

The invention relates to an anode material of a sodium lithium ion secondary battery and citrate preparation method thereof, the material has a molecular formula of Na3V2(PO4)2F3, while the space group is P42/mnm, belonging to tetragonal system with cell parameter a = 9.047, c = 10.705. By using NaF, NH4VO3, NH4H2PO4 as raw materials, adding saturated citrate solution via stirring, in order to prepare citrate ligand; then drying and milling into powder for preburing; pressing the powder, and buring in a turbular furnace loaded with nitrogen at a temperature of 600 to 700 centigrade, finally cooling naturally. The synthesized material can charge and discharge between 3.0 to 4.5 volts, with primary charging capacity of 126mAh/g, discharging capacity of 123mAh/g, efficiency of 97.6%, excellent circulation ability, having characteristics of single-phase, excellent crystallinity, small particle size and stable structure.

The invention discloses a desulphurization catalyst, and also discloses a preparation method of the desulphurization catalyst and the desulphurization catalyst prepared by the method, and an application of the desulphurization catalyst in desulphurization of sulfur-containing hydrocarbon oil. The desulphurization catalyst contains an aluminosilicate molecular sieve with a duodenary-ring pore-channel structure, rare earth oxide, titanium dioxide, a silicon oxide source, zinc oxide and active metal; the rare earth element content in the aluminosilicate molecular sieve with the duodenary-ring pore-channel structure is 0 mumg/g; and the characteristic peak of a tetragonal system of a rare earth-zirconiu composite oxide can be existed in a XRD spectrogram of the desulphurization catalyst. The desulphurization catalyst has better desulphurization activity and desulphurization stability.

The invention relates to a method for preparing a copper selenide nano-material by using Pantoea agglomerans. The copper selenide nano-material with three different stoichiometric ratios is prepared by adjusting the amount of a chemical reducing agent NaBH4 in a solution. When a ratio of n(EDTA-Cu):n(NaBH4) in a working medium solution is not greater than 4-8:1, the product is a Cu2Se nanosphere, and belongs to a tetragonal system, the primary sediment size is 20nm, and the secondary sediment size is 50-100nm; when the ratio of n(EDTA-Cu):n(NaBH4) in a working medium solution is greater than 4-8:1, the product is a CuSe nanosphere, and belongs to a hexagonal system, and the particle size is 100-200nm; and when the solution does not contain NaBH4, the product is a Cu2-xSe nanosphere, and belongs to a cubic system, and the particle size is uniform and is about 80nm. The problems of high cost, large energy consumption and environmental pollution existing in present copper selenide preparation methods are solved in the invention.

The invention relates to a compound boron rubidium sulfate, a boron rubidium sulfate crystal and a preparation method thereof. The chemical formula of the compound is Rb5BS4O16, the molecular weight is 822.40, the chemical formula of the compound boron rubidium sulfate crystal is Rb5BS4O16, the molecular weight is 822.40, the compound boron rubidium sulfate crystal belongs to a tetragonal system, the space group is P43212, the cell parameters are as follows: a is equal to 10.148(4) A0, c is equal to 16.689(14) A0, Z is equal to 4, V is equal to 1718.8(17) A3, the boron rubidium sulfate compound is prepared by a solid reaction process, the compound is used for growing crystal through a flux growth method to obtain the boron rubidium sulfate crystal, the prepared crystal has a large dimension of at least centimeter level, and the crystal has the advantages of wide transmission waveband, fast preparation speed, simplicity in operation, short growth period, good mechanical property and easiness for processing, and the like.

The invention relates to a preparation method for oil-soluble nano zirconium dioxide particles in a tetragonal crystal form by adopting an oil-water interface method. The preparation method comprises (1) a step of dropwise adding, at the room temperature, a zirconium oxychloride solution into a sodium oleate water solution, adding cyclohexane and stirring magnetically to obtain a mixture; (2) a step of transferring the mixture into a high-pressure hydrothermal reaction kettle, adding a sodium hydroxide solution until an oil-water volume ratio of the system is 1:1, and then reacting at 100-120 DEG C for 24-72 h; and (3) a step of separating the oil phase after the reaction is finished to obtain an oil phase product, washing alternately with ethanol and deionized water, and finally drying. The method has a simple operation method, good repeatability, easily controllable reaction conditions, and low requirements of temperature. The oil-soluble nano zirconium dioxide particles in the tetragonal crystal form having uniform particle size distribution and good dispersibility can be prepared without the need of calcination. Applications of the nano zirconium dioxide particles in oil phases are greatly improved. The method has a good application prospect.

The invention relates to a preparation method of a barium titanium silicate crystal, comprising the following steps of: heating the mixed system of the barium titanium silicate and a fluxing agent LiF and H3BO3 or B2O3, making the mixed system at the constant temperature and cooling to obtain a mixed solution; then putting a seed crystal into the mixed solution for cooling to prepare the crystal with the big dimensions of 1-100mm*1-100mm*1-100mm. The crystal prepared by the method belongs to a tetragonal system. The space group of the crystal is P4bm, the chemical formula of the crystal is Ba2TiSi2O8, the cell parameter of the crystal is shown as follows: a=b=8.518+/-0.002c=5.211+/-0.002Z=4, and the Moh's hardness of the crystal is 4-5. The method has high preparation speed and low cost and is simple to operate; and the obtained crystal has the advantages of big dimensions, good mechanical behavior, stable physical and chemical properties and the like, is free of deliquescence and is easy to process and store.

A titanium oxide nano tube material is configured so that crystal grains of a nano tube has a crystal structure oriented with the [001] direction of a tetragonal crystal system as a preferred direction. FWHM (Full Width at Half Maximum) of a rocking curve with respect to the (004) plane peak is 11.1 degrees to 20.3 degrees. The titanium oxide nano tube material has excellent photoelectric characteristics since the crystal grains of the nano tube are oriented with the (004) plane or the [001] direction of a tetragonal crystal system as a preferred direction.

The piezoelectric/electrostrictive body is represented by a composition formula ABO₃ (A includes at least one element selected from the group consisting of Li, Na and K, and B includes at least one element selected from the group consisting of Nb, Ta, Sb and Mn), and the body is formed so that a main phase is a tetragonal system, and the orientation degree of a (001) face after a polarization treatment is smaller than that of a (100) face, in a plane vertical to the applying direction of an electric field applied so as to perform the polarization treatment. The present inventive piezoelectric/electrostrictive body has a ratio between a diffraction peak intensity I₀₀₁ of the (001) face and a diffraction peak intensity I₁₀₀ of the (100) face of I₀₀₁/I₁₀₀≦1, in an X-ray diffraction pattern in the same plane after the polarization treatment.

The invention relates to a method for preparing a bismuth selenide micron-tablet, and belongs to the technical field of inorganic material preparation. The method comprises the following four steps: (1) preparing a spinning solution; (2) preparing a PVP/Bi(NO3)3 composite nano-fiber; (3) preparing a Bi2O3 nano-fiber, namely heating the PVP/Bi(NO3)3 composite nano-fiber; and (4) preparing a Bi2Se3 micron-tablet, namely selenizing the PVP/Bi(NO3)3 composite nano-fiber with selenium powder. The bismuth selenide micron-tablet has an excellent crystal form, belongs to the cubic system, and has a diameter of 4.46+/-0.16mu m and a thickness of 1.57+/-0.02mu m. The Bi2Se3 micron-tablet can be applied to the fields of thermoelectric materials, three-dimensional topping insulating materials, photo-catalysis and the like. The preparation method is simple and feasible, can be used for massive production, and has a wide application prospect.

The invention discloses a chiral zinc complex secondary structure hollow microsphere. The chemical formula of the microsphere is shown as ([ZnL(H2O)].0.5H2O) infinite, wherein L is 2,4-thiazolidine diacid anion; a zinc complex belongs to a tetragonal system, has a three-dimensional network structure and is formed by assembling ZnNO5 modules; the coordination geometric configuration of zinc ions is a deformed octahedron; and adjacent zinc ions are bridged through carboxyl to constitute a three-dimensional metal organic frame structure. In the preparation method, zinc acetate and H2L are taken as raw materials, water is taken as a solvent, PVP (Polyvinyl Pyrrolidone) is taken as a surfactant and acetone is taken as a precipitant. The invention has the advantages that: the chiral zinc complex secondary structure hollow microsphere represents stronger negative Cotton effect and larger specific surface area and has wide application prospect as a novel functional material; the preparation method is easy to operate and has low cost; the obtained product has a regular shape and high stability; and a new measure is explored for the introduction of a novel material.

The invention provides a laser crystal of sodium tungstate with waveband of 2 microns, belonging to a tetragonal system. The laser outputting the waveband of 2 microns has the characteristics of shortgrowth period, good integrality, high crystal yield, low threshold, high gain and the like. The prepared laser has high laser output efficiency and belongs to the field of photoelectron materials. The existing laser crystal of kalium and rare-earth compounded tungstate, mixed with rare-earth activated ion, has long growth period; furthermore, the laser crystal of rare-earth salt vanadate, mixed with the rare-earth activated ion, has the growing raw material with high melting point, thus easily causing segregation due to volatilization; and the grown crystal has bad thermal performance, is easy to crack and has colored core. The laser crystal is mixed with the rare-earth activated ion with the waveband of 2 microns, and the substrate is sodium and rare-earth compounded tungstate. The lasercrystal is applied to the fields such as distance measurement by laser, lidar, photoelectric interference, remote sensing, environmental detection, optical communication, medical treatment and the like.

To provide a piezoelectric thin film having an improved and stable characteristic by controlling stress applied during forming a piezoelectric thin film and providing the piezoelectric thin film having a perovskite structure. A thin film piezoelectric element in which a lower electrode is formed on a substrate, a piezoelectric thin film containing lead is formed on the lower electrode, and an upper electrode is further placed on the piezoelectric thin film, characterized in that the piezoelectric thin film is a dielectric with the perovskite structure having lead, zirconium, and titanium as the main ingredients, and is in a composition region in which, in the composition of the whole piezoelectric thin film, the. Zr/(Zr+Ti) ratio is not less than substantially 0.53, and has a crystal structure of the tetragonal system in which a c axis is longer than an a axis.

A ceramic sintered body includes tungsten carbide, zirconia, and alumina. The content of the tungsten carbide is 20 to 50 vol %, and the content of the zirconia is 5 to 25 vol %. The crystal phase of the zirconia is a tetragonal crystal or a mixture of tetragonal and monoclinic crystals. The ceramic sintered body does not substantially include Ti compounds. The average particle diameter of the tungsten carbide, the average particle diameter of the zirconia, and the average particle diameter of the alumina are all 1 μm or less.

The invention relates to a selenium-silicon-silver-barium compound, a selenium-silicon-silver-barium middle and far infrared non-linear optical crystal as well as a preparation method and application thereof. A chemical formula of the compound is BaAg2SiSe4, molecular weight of the compound is 697.01, the crystal is a tetragonal crystal system, a space group is of a non-centrosymmetry type (described in the specification), cell parameters comprise that a=b=7.066(3) angstrom, c=8.233(7) angstrom, alpha=beta=gamma=90 degrees and Z=2, and unit cell volume V=411.1(5) angstrom<3>. The preparation method comprises the step of carrying out solid-phase reaction on simple substances barium, silver, silicon and selenium under vacuum condition. Powder XRD spectra of the selenium-silicon-silver-barium compound and the selenium-silicon-silver-barium middle and far infrared non-linear optical crystal are consistent with theoretical values; and under irradiation of lasers with the wavelength of 2090nm, and frequency doubling effect of BaAg2SiSe4 with the granularity of 55-88 Mum is two times that of AgGaS2 with the same granularity.

The invention discloses a terephthalic acid uranyl coordination compound photocatalyst and a preparation method thereof, wherein the molecular formula of the photocatalyst is (H2-4,4'-bpy)[(UO2)2(TPA)3][4,4'-bpy=4,4'-bipyridine, TPA=terephthalic acid], the photocatalyst is yellow powder capable of being screened with a 100-mesh sieve and having a purity of not less than 99%, belongs to a tetragonal system, and has a p4<->21c space group structure, and the crystal cell parameters comprise that a is 23.203(3)angstrom, b is 23.203(3)angstrom, and c is 20.222(4)angstrom. According to the present invention, under the irradiation of an xenon lamp light source capable of simulating sunlight, with the photocatalyst, the RhB solution with the concentration of 20 mg/L can be degraded to 28.6% within 105 min; compared to the traditional TiO2, the photocatalyst of the present invention has the advantage of visible light response, and is the photocatalyst having good photocatalysis performance; and the preparation method has advantages of simple and easy-performing process, low requirements on equipment, and the like.