8results about How to "Dense growth" patented technology

The invention provides an aluminum alloy pretreatment method based on complex reaction, which comprises the following steps: S1, polishing an LDH (Layered Double Hydroxides) growth surface by using abrasive paper, and cleaning and drying; s2, preparing a complexing agent solution, wherein a complexing agent is selected from at least one of tannic acid, gallic acid and protocatechuic acid; s3, the aluminum alloy sample treated in the step S1 is put into the complexing agent solution in the step S2, and constant potential is applied to the aluminum alloy; s4, preparing a mixed solution of Zn (NO3) 2.6 H2O and NH4NO3, and adding an ammonia water solution to adjust the pH value to 6-6.5; s5, immersing the aluminum alloy treated in the step S3 into the mixed solution in the step S4, and putting the aluminum alloy into a constant-temperature water bath kettle to generate a Zn-Al-LDH film; and S6, after the hydrothermal reaction is finished, cooling to room temperature, and washing and drying the obtained reaction product. The surface of the aluminum alloy is pretreated through the complexing agent, the potential between an intermetallic compound and an aluminum matrix can be effectively balanced, the micro-couple effect is fundamentally inhibited, and ideal conditions are created for uniform, compact and defect-free growth of LDH.

The invention relates to the technical field of rebaudioside M crystals, in particular to a preparation process for improving fluidity of rebaudioside M crystals, which comprises the following steps: (1) taking a rebaudioside M raw material, adding a first solvent, heating and stirring to obtain a phase I solution for later use; (2) taking a second solvent of which the density is greater than that of the phase I solution as a phase II solution; taking a third solvent of which the density is smaller than that of the phase II solution as a phase III solution; and (3) adding the phase III solution in the step (2) into the phase II solution, taking the phase I solution in the step (1), controlling the temperature, adding, standing at constant temperature in a closed state until white flaky crystals appear in the phase I solution and at the interface of the phase I solution, the phase II and the phase III mixed solution, separating, leaching, and drying to obtain the rebaudioside M crystal. By adopting the preparation process, the rebaudioside M crystal with high flowability and high dissolution rate can be obtained.

The application relates to the field of advanced structural ceramics, and particularly discloses a gel injection molding method for preparing high-performance silicon nitride ceramics and a preparation method thereof. Raw materials include beta-SiN submicron powder 75 parts, YO submicron powder 8 parts, TiC submicron powder 5 parts, AlO superfine powder 5 parts, ZrO submicron powder 2 parts and wollastonite 5 parts in terms of mass ratio, a complex whisker regulator and an entry liquid are used, and ceramics are prepared through gel injection molding, dehydration, degreasing and gas pressure sintering. The grain morphology and interface combination are optimized through the whisker regulator, the slurry dispersion and the green body uniformity are improved through the entry liquid, and the product has a density greater than or equal to 99%, a Vickers hardness greater than or equal to 1700HV and a bending strength greater than or equal to 930MPa through 1700-1850 DEG C. gas pressure sintering, and the product has high density, high hardness, high toughness, wear resistance, corrosion resistance and long service life.

This invention discloses a method for preparing halide perovskite thin films and their applications. The preparation method includes the following steps: S1, providing a substrate; S2, mixing a precursor salt with a lactone solvent to form a precursor mixture; S3, depositing the obtained precursor solution onto the surface of the substrate and annealing it to form a perovskite thin film. This invention, by introducing a monocyclic lactone, overcomes the limitations of the traditional DMF / DMSO solvent system, significantly expanding the material compatibility range of solution processing, enabling stable film formation over a wider range of concentrations and temperatures. Utilizing the unique coordination ability and volatility characteristics of this type of lactone, crystallization kinetics can be effectively controlled, promoting more uniform and dense perovskite grain growth, significantly reducing the defect density inside the film, thereby obtaining a film with high crystallinity.

The invention belongs to the technical field of composite membrane preparation, and discloses a preparation method of an MOF / PVDF composite membrane for cation screening and a product, and the preparation method comprises the following steps: depositing ZnO particles on a PVDF substrate to obtain a ZnO-PVDF layer, fixedly installing the ZnO-PVDF layer on a polytetrafluoroethylene mold, and vertically placing the polytetrafluoroethylene mold in a reaction kettle; dissolving an organic ligand in absolute ethyl alcohol to obtain a ligand solution; adding the ligand solution into a reaction kettle, then adding a zinc nitrate aqueous solution into the reaction kettle, reacting for 24 hours under the vacuum condition of 100 DEG C to prepare a first intermediate product, cleaning the first intermediate product with deionized water, and performing vacuum drying to obtain a solvothermal film; the preparation method comprises the following steps: spin-coating a PDMS solution on a solvothermal film, drying at room temperature to obtain an MOF / PVDF composite film, and inducing MOF crystals to realize in-situ densified growth on the surface of a PVDF substrate by using ZnO as a heterogeneous nucleation site and a supplementary metal source, thereby fundamentally solving the intergranular micropore defect caused by particle aggregation and uneven distribution of a traditional blended film.

The invention relates to an application of a transporter and a gene thereof in improving tolerance of filamentous fungi to ionic liquid, and belongs to the technical field of genes. The invention aims to solve the problems that the stability of filamentous fungi in ionic liquid is poor at present, so that a fungus and ionic liquid synergistic technology is difficult to effectively apply and the like. The invention provides a transporter for improving tolerance of fungi to ionic liquid and a gene of the transporter. The nucleotide sequence of the transporter gene is shown as SEQ ID NO.1; the amino acid sequence of the transporter is as shown in SEQ ID NO. 2. After gene overexpression of the transporter provided by the invention, tolerance of filamentous fungus aspergillus terreus to ionic liquid is improved, including improvement of growth ability of a strain in the ionic liquid and improvement of activity of cellulase and hemicellulase of the strain in the ionic liquid.

This invention relates to the field of low-carbon building materials technology, specifically to a solid waste-based expansive activator and its preparation method. The expansive activator is made from steel slag powder, blast furnace slag powder, fly ash, desulfurized gypsum powder, and modified attapulgite clay powder. Its core innovation lies in a specific two-step mineralization modification of the attapulgite clay: first, an anionic nucleating agent and sodium carbonate are added for the first mineralization step; then, a cationic confinement agent and sodium carbonate are added for the second mineralization step; finally, heat treatment is performed for shaping. This method constructs a stable gradient porous functional layer in situ on the surface of the attapulgite clay. After mixing and pre-hydrating with solid waste raw materials, it can synergistically reduce the water demand of the cementitious system, promote the growth of hydration products to improve early strength, and significantly inhibit drying shrinkage by uniformly distributing the expansive components through anchoring. This invention effectively solves the technical problems of low early strength and poor volume stability in solid waste-based low-carbon cementitious materials.

The invention belongs to the technical field of electronic part manufacturing, and particularly relates to a controllable crystal orientation SnS2 resistive random access memory and a preparation method thereof. The preparation method comprises the following steps: evaporating the Au bottom electrode with the thickness of 300 nm on the surface of the SiO2 / Si substrate by adopting a vacuum evaporation method; and preparing the SnS2 resistive random access layer by adopting a tube sealing vulcanization method: evaporating a layer of Ag metal film by adopting a hard mask technology and a vacuum thermal evaporation method to complete the preparation of the controllable crystal orientation SnS2 resistive random access memory. According to the method, the required energy is low, and the generation of byproducts in a reaction system is further inhibited due to a high-vacuum closed environment in the sealing pipe, so that the process stability is improved; the requirement on equipment is low, and the production cost is effectively reduced.