39results about How to "Stable growth rate" patented technology

A method for preparing a vanadium pentoxide thin film by a sol-gel method, the invention relates to a method for preparing a vanadium pentoxide thin film. The present invention solves the problem of V prepared by existing vacuum evaporation method and sputtering method. 2 o 5 There are many oxygen vacancies in the film, poor process stability, low deposition rate, and low-valence vanadium oxides; the sol-gel method prepares V 2 o 5 Thin film requires high temperature melting V 2 o 5 Powder, aging time is long, preparation cycle is long, the film is usually rough and porous, and the quality is not high. Method: one, prepare V 2 o 5 Sol; 2. Deposition into film. The invention is used for preparing vanadium pentoxide film by sol-gel method.

The invention discloses a preparation method of anhydrous citric acid with specific granularity. The method comprises the following steps: carrying out multiple-effect evaporative concentration on an ion exchange treated citric acid acidolysis liquid, feeding the obtained multiple-effect concentrate to a crystallizer, carrying out continuous evaporative crystallization, and adding crystal seeds when the concentrate reaches certain supersaturation degree in order to induce crystal formation; adjusting the evaporation rate of a feed liquid and the addition rate of the multiple-effect concentrate in the crystallization process to control the supersaturation degree in order to stabilize the crystallization rate; arranging an online particle size determinator on the crystallizer, and discharging the obtained material when the granularity of crystals reaches required granularity; and centrifuging the obtained crystal slurry, and drying the centrifuged crystal slurry to obtain the anhydrous citric acid product with high purity, low water, uniform particles, concentrated granularity distribution, high bulk density and good anti-agglomeration capability. The anhydrous citric acid product obtained in the invention can meet different clients' requirements for the product granularity without screening, avoids the step of recovering and converting products with unsatisfactory granularity, reduces the energy consumption and improves the citric acid production efficiency.

The invention relates to a high-quality and rapid crystal growth control method, which belongs to the field of production process control. The crystal growth system includes a growth device, a control device and a vision-based size detection device. The DC servo motor drives the crystal carrier to rotate clockwise, stop, rotate counterclockwise, stop, and cycle. When the rotation of the crystal carrier stops, the size of the crystal is detected online by the vision system, and the cooling rate of the growth solution is adjusted according to the rules. The method of the invention reflects the supersaturated state of the growth solution through the growth rate of the crystal, which can not only ensure the stable and fast growth rate of the crystal, but also ensure the quality of the crystal.

The invention provides a method for preparing a high-quality silicon carbide crystal and a device thereof. The method comprises the steps of thermal field assembly, heating, crystal growing and cooling, wherein the step of thermal field assembly comprises the steps of putting a crystal growing raw material and silicon carbide seed crystal into a graphite crucible, setting a first lantern ring withthe heat conductivity greater than that of graphite on the outer wall of the graphite crucible roughly corresponding to the crystal growing material, and setting a second lantern ring with the heat conductivity less than that of graphite roughly corresponding to the silicon carbide seed crystal. The invention further provides a device for implementing the method. According to the preparation method and device of the silicon carbide crystal, introduction of other component or complicated preparation process is not required, carbon inclusion defect is prevented by controlling the thermal fieldin the crystal growing furnace, the risk of cracking crystal can be reduced, and the quality of silicon carbide crystal can be improved.

The invention relates to a method for compositing bismuth oxychloride pearlescent pigment. The method comprises the steps of taking bismuth inorganic salt as raw material, preparing bismuth oxychloride pearlescent pigment through the hydrolysis of bismuth inorganic salt in aqueous solution, dissolving the bismuth inorganic salt into diluted acid solution, feeding the solution into acidulated deionized water at a certain speed, meanwhile feeding aqueous alkali and acid produced during the reaction process into the solution, so as to maintain the pH value of a reaction system, and filtering, washing and drying on reaction liquid, so as to obtain bismuth oxychloride pearlescent pigment products. The bismuth oxychloride pearlescent pigment manufactured according to the method is uniform in appearance and good glossiness; the method has the advantages that the raw materials are price and easy to get, the technology is simple, parameters are convenient to adjust, the controllability is high, and the method has a wide application prospect.

The invention discloses a copper-zinc-tin-sulfur-based thin film precursor with a cyclic quantum well structure and a preparation method thereof. The preparation method includes: using a balance to accurately weigh the mass of the substrate before and after growth, and converting the mass by molar mass Obtain the amount of the corresponding precursor growth source material to obtain the relationship between the growth rate of the growth source, film thickness and growth time, and then control the ratio of each precursor growth source element by controlling the growth time, and then according to the growth time The division of copper-zinc-tin-sulfur-based film precursors for quantum well-like growth; also includes the use of magnetron sputtering, thermal evaporation or electron beam evaporation with high background vacuum, stable growth rate and high repeatability growth method. Based on the above preparation method, the present invention can precisely control the composition and element ratio of the thin film and its precursor, and solve the technical problem of the overall element ratio imbalance of the existing copper-zinc-tin-sulfur-based thin film.

The invention provides a crystal growth method of a polycrystalline silicon ingot, which comprises a heating stage, a melting stage, a growth stage, an annealing stage and a cooling stage; in the growth stage, from the beginning of the growth starts to the end of the top through, the temperature of a center region of the top of the polycrystalline silicon ingot is maintained at a constant value. According to the crystal growth method, the temperature gradient of the polycrystalline silicon ingot in the vertical direction in a growth process can be reduced, and thus the growth speed of the polycrystalline silicon ingot is more stable, impurities inside the polycrystalline silicon ingot are more uniformly segregated towards a liquid phase, the defect density inside a crystal of the polycrystalline silicon ingot can be effectively reduced, and the integral quality of the polycrystalline silicon ingot is improved, therefore, the battery efficiency of a single battery cell manufactured by adopting the polycrystalline silicon ingot and the integral proportion of the high-efficiency battery cell are increased.

The method for producing russula by rotating strong roots and controlling surface temperature and humidity in wild woodlands includes cutting trees in rotation, erecting water spray nets and covering thermal insulation films, controlling soil temperature and humidity in forest lands and strong roots to promote production; before the age of 21 years, through Adjust branch control canopy density between 0.7-0.8; Thinning trees in turn at age 21-25 years, but keep canopy density between 0.6-0.7, the stump height of thinning trees is 40-50cm, cultivate sprouting branches, after Cut down all the trees in 4-5 years; after 25 years of age, cut the larger sprouting branches in rotation, so that the number of sprouting branches per stump is maintained at 3-6, and the canopy density of the woodland is controlled between 0.7-0.8. The invention ensures the humidity and temperature required for the growth of Russula, reduces the damage of Russula to the extreme conditions in the field, prolongs its field growth time, increases the nutrition of roots in winter rotation, and improves the annual production batch of Russula and production.

The present invention provides a method for preparing compounded type humic acid water-retaining agent. Said method includes the following steps: adopting acrylic acid, starch and potassium hydroxide as main agent, compounding humic acid protective function group, controlling by items, respectively modifying and improving humate and potassium polyacrylate water-absorbing resin to make both them have reaction activity, then uniformly mixing them, and under the condition of heating and melting them making them implement compounding reaction so as to obtain the invented water-retaining agent with the function of promoting plant rooting, germination and growth.

The invention relates to a special fat powder for crayfish and a preparation method and application thereof. The special fat powder for crayfish comprises, in parts by weight: 10-30 parts of composite omega-3 functional fatty acid ester and 5-20 parts of yeast extract and carrier 30‑65 copies. In the invention, the compound omega 3 functional fatty acid ester, yeast extract and carrier in a specific weight ratio are mixed as a special fat powder for crayfish and added to the basic feed, so as to enhance the immunity of crayfish and improve the growth of crayfish by means of nutrient intake. performance, save resources, protect water quality, and improve economic benefits. In addition, the feed added with the fat powder has stable properties, is less prone to oil rancidity, and is less prone to bitterness and reduced nutritional value during processing and storage.