378 results about "Crystal system" patented technology

The invention relates to the technical field of crystal material preparation, in particular to a layered selenide Ge3Sb2Se5 semiconductor material and a preparation method thereof. The preparation method of the layered selenide Ge3Sb2Se5 semiconductor material comprises the following steps: grinding a Ge3Sb4Se7 material, putting the ground Ge3Sb4Se7 material into a quartz tube, adding iodine particles, performing vacuum packaging in the quartz tube, putting one end, with raw materials, of the quartz tube into a high-temperature region, and putting one end, without raw materials, of the quartz tube into a low-temperature region; raising the temperature to 400 + / -25 DEG C at the low-temperature region end and 500 + / -25 DEG C at the high-temperature region end, preserving heat for 7 days, and naturally cooling to room temperature to obtain the Ge3Sb2Se5 semiconductor material. The crystal structure of the Ge3Sb2Se5 semiconductor material belongs to an orthorhombic system, and the Ge3Sb2Se5 semiconductor material has the characteristics of low thermal conductivity and low resistivity. According to the preparation method disclosed by the invention, the Ge3Sb2Se5 semiconductor material can be stably prepared, and a material is provided for physical property research of the Ge3Sb2Se5 semiconductor material and preparation of semiconductor photoelectric devices and the like.

The invention discloses a method for refining grains of a titanium alloy. According to the method, an original low-oxygen-content titanium alloy plate is subjected to cryogenic pretreatment, the temperature of the core of the original low-oxygen-content titanium alloy plate is reduced to a certain temperature, then the cryogenic low-oxygen-content titanium alloy plate is fed into a rolling mill, the single-pass reduction rate is controlled, cryogenic rolling is completed, high refinement and uniform distribution of crystal grains are achieved, and the low-oxygen-content titanium alloy plate is obtained. And the rolled titanium alloy plate is subjected to subzero treatment again, and the titanium alloy plate of the complex twin crystal structure formed by intersection of {11-22} and {10-11} twin crystals is obtained. The method has the beneficial effects that under the synergistic effect of low oxygen and deep cooling, even under the extremely small deformation amount, the cross effect of various twin crystal systems can be efficiently activated, a high-density and complex twin crystal structure is formed, high refinement and uniform distribution of crystal grains are achieved, then the mechanical strength and low-temperature toughness of the material are remarkably improved, and the service life of the material is prolonged. And the application requirements in a severe low-temperature service environment are met.

To provide a ceramic having a high coefficient of thermal expansion and a low dielectric constant.SOLUTION: 50.0 to 90.0 mass% of 2MgO and SiO2, a total of 8.0 mass% or more of one of 7.0 to 14.0 mass% of ZrO2 and 10.0 to 50.0 mass% of Al2O3 or both of 14.0 mass% or less of ZrO2 and 50.0 mass% or less of Al2O3, and 3.0 to 15.0 mass% of one or more selected from Y2O3, CaO, CeO2, and HfO2, wherein a crystalline structure of the is a cubic structure. ZrO2.SELECTED DRAWING: None

The invention provides a preparation method and application of a compound cesium ammonium fluoborate and a cesium ammonium fluoborate nonlinear optical crystal. The chemical formula of the compound is CsNH4B8O12F2; the chemical formula of the crystal is CsNH4B8O12F2, the crystal belongs to a trigonal system, the space group is P321, and the unit cell parameters are as follows: a = b = 6.5858 (4) + / -0.02, c = 7.8163 (6) + / -0.02, alpha = beta = 90 degrees, gamma = 120 degrees and Z = 1. The crystal is grown by adopting a vacuum high-temperature solution method, a room-temperature solution method or a hydrothermal method, and the ultraviolet transmission cut-off edge of the crystal is lower than 190 nm. The nonlinear optical effect of the crystal is about 2.5 times of that of KH2PO4 (KDP), and the shortest I-type phase matching wavelength is 175.5 nm. The crystal has the advantages of simple preparation method, low toxicity of used initial raw materials, small harm to human bodies, stable physical and chemical properties, uniaxial crystal, easiness in application and the like. The method can be widely applied to nonlinear optical devices such as ultraviolet and deep ultraviolet all-solid-state lasers, optical parametric oscillators and the like.

A quantum entanglement system comprising a laser system, a spontaneous parametric down conversion crystal system, and a thermal management system. The laser system is configured to generate a laser beam. The spontaneous parametric down conversion crystal system comprises a spontaneous parametric down conversion crystal configured to receive the laser beam at a spontaneous parametric down conversion crystal and generate an entangled photon pair in response to the spontaneous parametric down conversion crystal receiving the laser beam. The thermal management system is configured to maintain the spontaneous parametric down conversion crystal at an annealing temperature during a generation of the entangled photon pair. A translation system is configured to move a position of the spontaneous parametric down conversion crystal. A

The present invention relates to composite tungsten oxide particles containing a composite tungsten oxide represented by the general formula MxWyOz (wherein M element is one or more elements selected from the group consisting of alkali metal elements, alkaline earth metal elements, rare earth elements, Mg, Zr, Cr, Mn, Fe, Ru, Co, Rh, Ir, Ni, Pd, Pt, Cu, Ag, Au, Zn, Cd, Al, Ga, In, Tl, Si, Ge, Sn, Pb, Sb, B, F, P, S, Se, Br, Te, Ti, Nb, V, Mo, Ta, Re, Be, Hf, Os, Bi, and I, 0.20 < = x / y < = 0.37, 2.2 < = z / y < = 3.3), and having a hexagonal crystal system, in which when observed in STEM-HAADF 0.01% to 10% inclusive of the Z contrast of W atoms is reduced to 95% or less of the average value.

This invention relates to a compound, magnesium gallium selenide (MgHgGa4Se8), and a magnesium gallium selenide (MgHgGa4Se8) infrared nonlinear optical crystal, along with their preparation methods and applications. The compound has the molecular formula MgHgGa4Se8 and a molecular weight of 1135.46 g / mol. The crystal, also with the molecular formula MgHgGa4Se8 and a molecular weight of 1135.46 g / mol, lacks a center of symmetry, belongs to the tetragonal crystal system, and has a space group of MgHgGa4Se8. Its cell parameters are α = β = γ = 90°, Z = 1, and its volume is determined by the high-temperature melt method, chemical vapor transport method, or crucible lowering method. This crystal exhibits advantages such as significant nonlinear optical effects, good crystal growth habit, good mechanical properties, high hardness, resistance to breakage and deliquescence, and ease of processing and storage. It can be used to fabricate infrared nonlinear optical devices, which have important applications in optoelectronic warfare, laser communication, and medical fields.

The invention belongs to the technical field of chiral material preparation, and particularly relates to a one-dimensional bismuth-based chiral perovskite crystal and a preparation method and application thereof. The general formula of the chiral perovskite crystal is (R-beta-MPA) 2BiI5 or (S-beta-MPA) 2BiI5, the chemical formula of the chiral perovskite crystal is C18H28BiI5N2, the R-beta-MPA represents (R)-(+)-beta-methyl phenylethylamine, the S-beta-MPA represents (S)-(-)-beta-methyl phenylethylamine, the R-beta-MPA represents (R)-(+)-beta-methyl phenylethylamine, and the S-beta-MPA represents (S)-(-)-beta-methyl phenylethylamine. The crystallographic data of the (R-beta-MPA) 2BiI5 include that the crystal belongs to an orthorhombic crystal system and a P212121 space group, and the cell parameters are as follows: alpha is equal to 90 degrees, beta is equal to 90 degrees, and gamma is equal to 90 degrees; the crystallographic data of the (S-beta-MPA) 2BiI5 comprises that the crystal belongs to an orthorhombic crystal system and a P212121 space group, and the cell parameters are as follows: alpha is equal to 90 degrees, beta is equal to 90 degrees, and gamma is equal to 90 degrees.

Provided is a rare earth magnet alloy having a tetragonal R2Fe14B crystal structure, including: a main phase containing, as main constituent elements, at least one kind selected from the group consisting of: Nd; La; and Sm, Fe, and B; and a sub-phase containing, as main constituent elements, at least one kind selected from the group consisting of: Nd; La; and Sm, and O, wherein La substitutes for at least one of a Nd(f) site or a Nd(g) site, wherein Sm substitutes for at least one of a Nd(f) site or a Nd(g) site, wherein La segregates in the sub-phase, and wherein Sm is dispersed in the main phase and the sub-phase without segregation.

This invention discloses a polyoxometalate that catalyzes the Knoevenagel reaction, its preparation method, and its applications. The chemical formula of the polyoxometalate that catalyzes the Knoevenagel reaction is: H3[K(H2O)6][K2(H2O) 10 ]2[Cu(en)2(H2O)2][Cu(en)2(Nb6O 19 Cu(en))2·24H2O, where en = ethylenediamine; the polyoxometalate crystals catalyzing the Knoevenagel reaction belong to the triclinic crystal system with space group P-1; the polyoxometalates catalyzing the Knoevenagel reaction prepared in this invention exhibit excellent heterogeneous catalytic performance in the highly efficient Knoevenagel condensation reaction, showing high yield and high stability under isothermal conditions at a 1:1 substrate ratio and over a wide substrate range. The superior catalytic ability of the polyoxometalates catalyzing the Knoevenagel reaction can be attributed to the presence of dense and effective basic sites on the surface of the heteropolycationic chain, and the increased contact frequency between the organic-inorganic hybrid catalyst and the substrate.

The application discloses a preparation method of vanadium-doped and high-hydrated mangan-chromian spinel monocrystal under high temperature and high pressure. The cylindrical mangan-chromian spinel sample is prepared by taking solid rose triangular rhombic manganese carbonate crystal, solid chromium (III) acetate hydroxide crystalline powder, solid vanadium (IV) acetylacetonate oxide powder, solid oxalic acid powder, solid bixbyite powder, solid chromium hydroxide powder and liquid dilute nitric acid as starting raw materials; two pieces of water source sheets are made from the bixbyite powder and the chromium hydroxide powder with a weight ratio of 4:1; the two pieces of water source sheets are placed at two ends of the cylindrical mangan-chromian spinel sample and then are placed into a double-capsule structure experimental sample bin with an inner layer sleeve being a graphite tube and an outer layer sleeve being a gold-palladium alloy tube; the high temperature and high pressure reaction is carried out to obtain the mangan-chromian spinel monocrystal; and the preparation technology blank of the vanadium-doped and high-hydrated mangan-chromian spinel large-particle monocrystal under the current high temperature and high pressure conditions is solved.

The invention discloses a low-thermal-conductivity p-type liquid thermoelectric material and a preparation method thereof. The chemical formula of the low-thermal-conductivity p-type liquid thermoelectric material is Cu6GeTeS4, the low-thermal-conductivity p-type liquid thermoelectric material belongs to a cubic system and a space group, the low-thermal-conductivity p-type liquid thermoelectric material Cu6GeTeS4 forms an anion rigid framework by GeS4 tetrahedral elements isolated in unit cells and body-centered cubic Te, and Cu ions move in the framework. The p-type liquid thermoelectric material keeps a stable cubic phase at 300-873 K, and has low thermal conductivity and a high thermoelectric figure of merit; the ultra-low thermal conductivity of 0.69 to 0.57 W m <-1 > K <-1 > is realized at 300 to 873 K.

This invention provides an organic ferroelectric eutectic material, its preparation method, and its applications, relating to the field of ferroelectric materials technology. The organic ferroelectric eutectic material constructs a crystal system with "rigid constraint and flexible adaptation coexisting, dipole order and controllable polarization synchronously" through "molecular selection-supramolecular assembly-crystal structure regulation," achieving a synergistic effect of high Curie temperature, strong polarization characteristics, and excellent flexibility. The preparation method of the organic ferroelectric eutectic material utilizes a simplified "solvent dissolution-solvent evaporation" process, leveraging the mediating effect of the solvent to promote the supramolecular self-assembly of donor and acceptor molecules. This achieves the preparation of an organic ferroelectric eutectic material possessing both high Curie temperature, strong polarization characteristics, and excellent flexibility. The preparation method has multiple advantages, including "stable process, low cost, and suitability for large-area processing," making it a simple, efficient, and universally applicable preparation method suitable for large-scale industrial production.

This invention relates to the field of chemical pharmaceuticals, and more particularly to a mebendazole crystal form and its preparation method. The mebendazole crystal form has a single-crystal structure belonging to the triclinic crystal system; space group Triclinic P; cell parameters a = 6.10 Å, b = 15.69 Å, c = 20.35 Å; α = 94.14°; β = 97.22°, γ = 90.70°, V = 1926 Å. 3 The optimization and development of the crystalline form of p-toluimidazole provided by this invention is of great value.

The invention relates to a novel second-order nonlinear optical crystal-potassium cadmium germanate (K4Cd3Ge4O13), and belongs to the field of optical crystal materials. The crystal is prepared by adopting a high-temperature solid-phase method and a high-temperature solution method, belongs to an orthorhombic crystal system and a C2 space group, is accurate in measurement of cell parameters, and shows excellent nonlinear optical characteristics and a wide light transmission range. The ultraviolet cut-off edge of the crystal is 261 nm, the infrared spectrum permeability is not obviously reduced in the range of 4000-714 cm <-1 >, the transmission range of the crystal can effectively cover a key atmosphere transmission window of 3-5 microns, and the crystal has powder frequency doubling response equivalent to that of a KDP crystal and can be applied to an all-solid-state laser as a mid-infrared nonlinear optical crystal.

This invention belongs to the field of fuel cell technology, specifically relating to a method for preparing and applying a hydrogen-bonded organic framework material with high proton conductivity constructed from carboxylic acid-aminoguanidine. The chemical formula of this organic framework material is [(CN4H7)(C 10 [O8H5], this organic framework material belongs to the triclinic crystal system. P Space group 1, cell parameters: a =7.9901(4)Å, b =9.6412(3)Å, c =9.6724(4)Å, α =96.322(3)°, β =113.876(4)°, c =93.633(3)°. The hydrogen-bonded organic framework material constructed by carboxylic acid-aminoguanidine and the composite film prepared therefrom have high proton conductivity and are highly promising proton conduction materials.

This invention relates to a potassium hydroxyborate nonlinear optical crystal, its preparation method, and its applications. The crystal has the chemical formula K₂B₅O₈(OH), a molecular weight of 277.26, belongs to the orthorhombic crystal system, and has a space group of [missing information]. Pca 21, with unit cell parameters a=8.5523(8)Å, b=7.3326(7)Å, c=12.9739(10)Å, α=β=γ=90°, V=813.60(13)Å. 3 A nonlinear optical crystal composed of potassium hydroxyborate can be obtained using a mild hydrothermal (solvothermal) method through programmed or natural cooling. The frequency doubling effect of this crystal powder is approximately twice that of KDP (KH₂PO₄), and its ultraviolet cutoff edge is below 200 nm, making it suitable as a deep-ultraviolet nonlinear optical crystal. The crystal growth process offers advantages such as simple operation, low raw material toxicity, short growth cycle, low cost, and stable physicochemical properties. It has been widely applied in the fabrication of nonlinear optical devices such as frequency doubling generators, up- or down-frequency converters, or optical parametric oscillators.

This application discloses an inorganic compound crystal, its preparation method, and its applications. The inorganic compound crystal has the chemical formula Ga2(OH)(TeO3)(Te2O5)Br, belongs to the orthorhombic crystal system, has a space group of Pca21, and unit cell parameters α=β=γ=90°, Z=4. The inorganic compound crystal is prepared using a hydrothermal method. Under 1064nm laser irradiation, the powder frequency doubling intensity of the inorganic compound crystal Ga2(OH)(TeO3)(Te2O5)Br is 9.8 times that of KH2PO4(KDP), and phase matching can be achieved, indicating its significant potential application value as a nonlinear optical material.

The invention discloses a method and system for determining anisotropic thermoelectric performance of a material based on tensor inversion, and the method comprises the steps: obtaining an Euler angle of a single crystal or texture polycrystalline sample in any orientation through electron back scattering diffraction, and building a rotation matrix between a sample coordinate system and a crystal coordinate system; measuring thermoelectric parameters such as resistivity, thermal conductivity and / or Seebeck coefficient under the sample coordinate system; and constructing a linear equation set based on a second-order tensor rotation formula, and inversely solving an intrinsic thermoelectric tensor component under a crystal coordinate system. According to the method, the intrinsic anisotropic thermoelectric performance of the material along the crystal main axis can be accurately obtained without strict crystal orientation cutting, and the method has the advantages of being high in universality, high in precision, easy and convenient to operate and the like and is suitable for high-throughput characterization of complex crystal system materials and device optimization design.

The application discloses 4-nitrobenzoic acid imidazole quaternary ammonium salt and a preparation method and application thereof. The 4-nitrobenzoic acid imidazole quaternary ammonium salt provided by the application has a structure as shown in formula (I), is in a single crystal form, is in a triclinic crystal system, and belongs to a P-1 space group. The 4-nitrobenzoic acid imidazole quaternary ammonium salt has a significant bacteriostatic effect, good thermal stability, and can be applied to preparation of antibacterial materials as an antibacterial agent.

The invention belongs to the technical field of photothermal conversion materials, and discloses a preparation method and application of an inorganic-organic hybrid polyoxotungstate photothermal material with wide spectrum absorption. The structural formula of the photo-thermal material is Per4W10O32, the crystal structure belongs to a triclinic system, the space group is P-1, and the photo-thermal material has specific unit cell parameters. The preparation method comprises the following steps: oxidizing perylene molecules through constant current electrolysis in a mixed solvent system containing perylene molecules and a decatungstate precursor in an electrochemical oxidation manner, and assembling the oxidized perylene molecules with decatungstate anions to form bulk crystals; the photo-thermal material has continuous strong absorption in a region from ultraviolet light to short wave infrared, the photo-thermal conversion efficiency is as high as 98.24%, when the photo-thermal material is applied to the fields of solar driven interface photo-thermal evaporation and water treatment, the evaporation rate of a two-dimensional system is 1.89 kg.m <-2 >. H <-1 >, the evaporation rate of a three-dimensional hydrogel system is increased to 3.02 kg.m <-2 >. H <-1 >, salt deposition can be inhibited in long-term seawater desalination operation, and the photo-thermal material has a good application prospect. Fresh water quality meets drinking water standards.

The application discloses a kind of cubic system tricobalt tetroxide quantum dots solvent hot preparation method, comprising the following steps: the mixture is obtained by mixing with set proportion with the source of cobalt, alcohol, polyvinylpyrrolidone, deionized water and hydrogen peroxide;The mixture is heated to a preset temperature in a sealed container with a predetermined volume ratio and isothermal reaction for a set time;When the reaction is finished, the reaction product is cooled to room temperature and washed, and the cubic system tricobalt tetroxide quantum dots are obtained after drying.The cubic system tricobalt tetroxide quantum dots with specific crystal structure can be obtained under the optimal preparation conditions, and the tricobalt tetroxide quantum dots with high uniformity of particle size and particle dispersion can be obtained;It can be applied in catalysis, energy storage and sensing fields, and the preparation process is simple and easy to operate, with good repeatability, low energy consumption and low cost, and the process parameters can be scaled up or down, suitable for industrial mass production.

This invention discloses a method for preparing and applying a gold cluster scintillator protected by a stable luminescent free radical ligand. The scintillator material uses (3,5-dichloro-4-pyridine)bis(2,4,6-trichlorobenzene)methyl free radical (PyBTM) as a ligand, and a chain-like tetranuclear free radical cluster is constructed using a one-pot method. The chemical formula of the compound is [Au4(PNP)2(PyBTM)2](SbF6)4, belonging to the triclinic crystal system, space group R-3. This free radical cluster scintillator achieves 100% theoretical exciton utilization and a short radiation decay lifetime due to its unique doublet emission mechanism. These properties make it an ideal candidate material for overcoming the contradiction between high luminous yield and fast response in traditional scintillators. Due to the excellent thermal and water-oxygen stability of this system, it can be fabricated into a scintillator screen to further achieve high-quality X-ray imaging with a spatial resolution of up to 31 LP·mm. ‑1 This provides a general design strategy for high-performance radiation detection materials.

The invention relates to the technical field of photocatalysis, in particular to a strontium bismuth vanadium oxide photocatalyst and a preparation method and application thereof.The chemical formula of the photocatalyst is Sr3. 59Bi19.41 V4O42, the crystal structure of the photocatalyst belongs to an orthorhombic system, the space group of the photocatalyst is Immm, and the photocatalyst is of a unique layered structure composed of cation triple plate layers; the photocatalyst is synthesized by a molten salt method, and shows the activity of photocatalytic decomposition of water to produce oxygen under visible light. The preparation method comprises the following steps: mixing and grinding SrO, Bi2O3 and VO precursors with a molten salt medium, and then carrying out temperature programming calcination to synthesize a target product; the catalyst prepared by the method has the characteristics of high crystallinity, few defects and regular morphology, the photocatalytic oxygen production performance of the catalyst is remarkably superior to that of a same-component sample synthesized by a traditional solid-phase method, and photocatalytic water decomposition and oxygen production can be realized by taking a silver nitrate, ferric nitrate, ferric chloride or potassium ferricyanide aqueous solution as a sacrificial agent system under the irradiation of visible light with the wavelength of more than or equal to 420 nm.

The invention discloses a sulfur-arsenic-strontium-sodium compound and a sulfur-arsenic-strontium-sodium nonlinear optical crystal as well as a preparation method and application thereof. The chemical formula of the sulfur-arsenic-strontium-sodium nonlinear optical crystal is Na4SrAs2S8, the sulfur-arsenic-strontium-sodium nonlinear optical crystal is of a non-centrosymmetric structure and belongs to a tetragonal system, and a space group is that cell parameters are alpha = beta = gamma = 90 degrees, Z = 2 and V = 701.57 (5). The sulfur-arsenic-strontium-sodium nonlinear optical crystal provided by the invention has a relatively large nonlinear optical coefficient and relatively wide transmission wave band and band gap. Meanwhile, the crystal meets the same-component melting characteristic, is easy to grow, cut, grind, polish and preserve, is stable in air, is not easy to deliquesce and is insoluble in water, so that the crystal is expected to become a new-generation novel middle-infrared band nonlinear optical material with excellent comprehensive performance, and can be effectively applied to a wide-spectrum-range tunable laser system.

The application provides a 2-amino terephthalic acid dimethyl ester-tetracyano benzene eutectic crystal as well as a preparation method and application thereof, the eutectic crystal is of a triclinic system, a space group is a cell parameter is alpha = 95.041 (2) °, beta = 90.337 (2) °, gamma = 97.670 (2) °, and a cell volume is The 2-amino terephthalic acid dimethyl ester-tetracyano benzene eutectic crystal provided by the application increases the solid melting point of the organic compound from 133.39 DEG C to 162.23 DEG C without changing the covalent bond of the compound, enhances the thermal stability, and meanwhile, the fluorescence emission color, the fluorescence lifetime and the quantum yield are obviously changed.

Cell parameters of the crystal compound are as follows: diffraction data are collected in an omega-theta scanning mode by using MoK alpha rays monochromatized by a graphite monochromator on an Oxford X-ray single crystal diffractometer at the temperature of 273 k, and the crystal compound is characterized in that the crystal belongs to a triclinic system, P-1; the cell parameters are as follows: alpha is equal to 79.857 (3) degrees; beta is equal to 87.082 (3) degrees; gamma is equal to 87.829 (3) degrees; the synthesis method of the crystal chlorine compound (I) comprises the following steps: weighing 0.02 35 g of benzophenone hydrazone and 0.6720 g of 1.0 g of 7-chloroisatin and acetic acid ketone monohydrate complex, putting into a 150mL flask, adding 100.0 mL of chlorobenzene as a solvent, stirring at room temperature for 48 hours, carrying out column chromatography separation, eluting with petroleum ether / dichloromethane (1 / 1), and carrying out vacuum drying to obtain the crystal chlorine compound (I). And naturally volatilizing the collected front component points to obtain the target crystal compound I, namely the 6-bromo-3-diphenylmethylene indoline-2-ketone crystal. The application of the crystal chlorine compound (I) is that the crystal chlorine compound (I) has a relatively strong inhibition effect on epidermophyton flocculent, and the IC50 value of the crystal chlorine compound (I) is 0.063 + / -0.008.

The invention belongs to the technical field of material science foundation, and discloses a method for predicting twinning transmission probability of different crystal systems. Aiming at the characteristic that cross-crystal system twinning transfer needs to experience distinct reconstruction mechanism characteristics in an allotropical system interface, by introducing crystal symmetry and twinning system variant spatial orientation, the minimum orientation difference from rotation of matrix crystal grains to generation of a parallel twinning system is determined, and the alignment difficulty of twinning faces and twinning directions of two crystal systems at the interface is quantified. The method breaks through the limitation of homomorphic system symmetry hypothesis, can analyze the microscopic matching mechanism of heteromorphic system interface twinning activation, and clarifies the constraint effect of lattice parameter difference on twinning system preferential activation and transmission. The method is suitable for strength and toughness collaborative optimization design of complex multiphase systems such as heterojunction interfaces.

The invention discloses a preparation method and application of a novel MOF material, and belongs to the technical field of gas separation. According to the preparation method, a heat-assisted mechanical force method and low-temperature calcination are combined, the pre-organization degree of the precursor is remarkably improved by combining ball-milling pretreatment with a solvation effect, and directional growth of a long-range ordered M-O-C bond network is realized in the calcination process, so that the high-crystallinity single-phase MOF is prepared. The prepared MOF material belongs to an orthorhombic system, the diameter of more than 95% of pore channels is smaller than the diameter of cavities, the MOF provided by the invention has industrial application potential, the preparation cost of the material can be remarkably reduced, and the separation coefficient is greater than 3800 when CO2 / N2 / CH4 is separated under the conditions of 298K and 10bar.

This invention provides a positive electrode active material and its application. The positive electrode active material of this invention comprises matrix particles including lithium metal oxide and a graphite coating layer covering at least a portion of the surface of the matrix particles; the lithium metal oxide has the structure shown in Formula 1; in the X-ray diffraction pattern, the lithium metal oxide is a cubic crystal system in space group Cmca, and has a 002 peak with a 2θ of 17.9°–18.1° and a 131 peak with a 2θ of 67.0°–67.5°; Li n‑y Na y Co 1‑a M a O2, Equation 1, where 0.6 ≤ n ≤ 0.8, 0 < y ≤ 0.05, 0 ≤ a < 0.2; and M is a doping element. The unique composition and crystal structure of this positive electrode active material help improve the battery's specific capacity and cycle performance, especially under high-voltage conditions, enabling the battery to maintain excellent performance.