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

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 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 discloses a raw material sintering process of silicon carbide crystals grown by a PVT (physical vapor deposition) method. The silicon carbide raw material is led to the sintering processwith the PVT method, a sintering fixture is designed, the silicon carbide is sintered through the previously designed sintering fixture, and the silicon carbide crystals are grown by the PVT method.The raw material sintering process has the advantages that the silicon carbide raw material forms a certain structure through sintering of the silicon carbide raw material, crystallization of the silicon carbide raw material is weakened, densification degree of the silicon carbide raw material is lowered, impurities carried in the silicon carbide raw material can be removed during sintering, fullsublimation and stable growth speed of the silicon carbide crystals by the PVT method can be effectively controlled and maintained, and the yield of the utilization of the silicon carbide raw materialand the silicon carbide crystals is increased.

The invention provides an improved structure of a single crystal furnace for growing large-size sapphire. The improved structure comprises an upper thermal insulation structure, side thermal insulation structures and a bottom thermal insulation structure, wherein the upper thermal insulation structure and the bottom thermal insulation structure are identical to those in patents of the earlier stage; the difference resides in that the thicknesses of the thermal insulation layers are gradually reduced from top to bottom instead of identical thicknesses of upper and lower structures of the side thermal insulation structures, the diameter of a birdcage-like heating body is gradually reduced from top to bottom, and the heating body is in a shape of an inverted cone. The thermal field is uniform and reasonable, the crystal growth rate is stable, defects that crystals generates clouds, are glued on pots and the like can be effectively reduced, the dependence on a process control worker is low, and the crystal growth yield is high.

The invention relates to a crystal growth process control method based on solution concentration online estimation, and belongs to the field of production process control. The crystal growth system comprises a growth device, a control device and a vision-based size detection device. And a crystal carrying frame rotates clockwise, stops, rotates anticlockwise and stops to circularly operate. When the crystal carrying frame stops rotating, the size of the growing crystal is detected on line through a visual system, the concentration of the growing solution is estimated on line according to the size of the growing crystal so as to calculate the supersaturation degree of the growing solution, the cooling rate of the growing solution is adjusted regularly according to the supersaturation degreerequirement, and the temperature of the growing solution is changed. According to the method, the temperature of the growing solution is changed through the change of the supersaturation degree of the growing solution, so that the crystal can have a stable and rapid growth speed, and the quality of the crystal can be guaranteed.

The invention relates to a device and method for controlling a radial temperature gradient of silicon carbide monocrystalline growth. The device comprises a carbon-fiber cone-shaped air blowing device arranged on a crucible cover, an upper port of the carbon-fiber cone-shaped air blowing device is connected with a carbon-fiber tee joint, one port of the carbon-fiber tee joint is connected with a frequency-conversion circulating air device, another port of the carbon-fiber tee joint is connected with a thermodetector, and the frequency-conversion circulating air device and the thermodetector are both connected with a PLC control system. The method comprises the steps that a technological set temperature is compared with a temperature measured by the thermodetector, and the PLC control system sends a signal to the frequency-conversion circulating air device to adjust the temperature. According to the device and method for controlling the radial temperature gradient of silicon carbide monocrystalline growth, the radial temperature can be changed without changing the radial position, the radial temperature can be adjusted automatically, the temperature is set according to the needs of a grown crystal, the stable radial temperature is maintained, it can be guaranteed that the crystal grows at the optimum temperature all the time, the crystal grows stably, and the crystal quality is improved.

The invention relates to a preparation method of a cathode active material of a lithium ion battery. The preparation method comprises the following steps: providing a metal (M) source which can be dissolved in a first liquid-phase solvent and preparing a metal ion (M<x+>) solution by using the first liquid-phase solvent, wherein the metal element M comprises one or more of Mn, Co, Ni, Fe and V; selecting lithium carbonate as a precipitant and preparing lithium carbonate suspension; adding the metal ion solution into the lithium carbonate suspension to form a mixed solution for precipitation reaction to obtain carbonate precipitate; separating and drying the carbonate precipitate; mixing the carbonate precipitate with a lithium source uniformly and sintering to obtain the cathode active material of the lithium ion battery.

The invention relates to a cell strain for culture of PRRSV and application thereof. The cell strain is highly sensitive to PRRSV, is stable and can continuously and stably proliferate high-titer PRRSV. The cell strain is free of pollution by mycoplasma, bacteria, fungi and exogenous viruses, does not has mutagenicity, teratogenicity and carcinogenicity and has high security. When used in enrichment culture of PRRSV, the PRRSV is more beneficial for reproduction and proliferation of PRRSV compared with Marc145 blast cells. Thus, application of the cell strain for enrichment culture of high-titer PRRSV is favorable for obtainment of more comprehensive information about research and epidemic prevention of PRRSV and for more direct and effective research. The monkey kidney cell line Marc145-1 strain highly sensitive to PRRSV and a high-titer PRRSV proliferation method have wide development and application prospects in research and epidemic prevention of PRRSV.

The invention discloses a device and a method for reducing generation of 4H-SiC polymorphic defects, and belongs to the field of crystal growth devices. The crystal growth device solves the problems that an existing crystal growth device for growing 4H-SiC crystals is prone to generating multiple crystal forms in the crystal growth process, and the crystal growth quality is poor. The device comprises a crucible upper cover, an outer crucible, an inner crucible, a connecting plate, a supporting table, an induction coil and a quartz tube, the outer crucible is arranged on the upper side of the supporting table, the inner crucible is sleeved with the outer crucible, the crucible upper cover is arranged on the outer crucible, seed crystals are arranged on the inner wall of the crucible upper cover, the inner crucible is filled with raw materials, the inner crucible is arranged on the connecting plate, the connecting plate is in threaded connection with the threaded rod, the threaded rod is arranged in the supporting table and penetrates through the connecting plate to be connected with the inner crucible, the supporting table and the outer crucible are arranged in the quartz tube, and the induction coil is arranged on the outer side of the quartz tube. According to the crystal growth device and method, the stable crystal growth rate is realized, and the generation of crystal growth defects is reduced.

The invention discloses a bacteriostatic and detoxicating composite biocontrol inoculant for relieving watermelon continuous cropping obstacles. The composite biocontrol inoculant comprises the following strains: Exiguobacterium acetylbacter PNC25 (the preservation number is GDMCC NO.60108), Bacillus pumilus FR026 (the preservation number is GDMCC NO.60725) and Bacillus licheniformis CHS55 (the preservation number is CGMCC NO.4738). The preparation method of the composite biocontrol inoculant comprises the step of compounding fermentation broth of the strains according to the volume ratio of 1:1:1. The composite antibiological inoculant provided by the invention combines the biocontrol characteristics of three strains, has good dual functions of bacteriostasis and detoxification, has a strong antagonistic effect on watermelon fusarium oxysporum, has a field control effect as high as 61.1 percent, has a better use effect than a single strain, and can promote the growth of watermelons through autotoxic substances; and the compounding of the three bacteria helps combine the metabolic functions of the bacteria and stabilize the growth rate of the bacteria under the condition of the presence of autotoxic substances.

The present invention relates to procambarus clarkii special fat powder, and a preparation method and an application thereof. The procambarus clarkii special fat powder comprises the following components in parts by weight: 10-30 parts of compound omega-3 functional fatty acid ester, 5-20 parts of a yeast extract and 30-65 parts of a carrier. A mixture of the compound omega-3 functional fatty acidester, yeast extract and carrier at the specific weight ratio is used as the procambarus clarkii special fat powder to be added into a basic feed, and a nutritional intake method is used to improve immunity of procambarus clarkii, improves growth performance of the procambarus clarkii, saves resources, protects water quality, and improves economic efficiency. In addition, the feed added with thefat powder has stable properties and is not prone to rancidity, bitterness and reduced nutritional value during processing and storage processes.

The invention discloses multi-element composite water-soluble fertilizer solid powder prepared from antibiotic mushroom dregs and a method and application thereof. The method comprises the steps: putting the antibiotic mushroom dregs into a reaction kettle, and using hydrochloric acid for directional hydrolysis of the antibiotic mushroom dregs; carrying out reduced pressure distillation under vacuum to recover hydrochloric acid; adding activated carbon for decoloration and impurity removal, and absorbing salinity and insoluble organic matter; centrifugally collecting supernatant hydrolysis mother liquor; diluting the hydrolysis mother liquor under an acidic condition, and adding a solid trace element material for chelating; and adding calcium hydroxide to adjust the pH value, centrifugingto remove calcium sulfate precipitate and impurities, and volatilizing under negative pressure to prepare water-soluble fertilizer solid powder. The prepared multi-element water-soluble fertilizer solid powder can be applied to gardening, fruits and vegetables, farmlands, forests or urban landscaping lands and can degrade and remove residual antibiotics in the antibiotic fungi residues, avoid large fertilizer efficiency loss and unreasonable nutrition proportion in the degradation and removal process, improve the recovery efficiency of amino acids and reduce the loss of phytostimulant-like nutrient substances.

The invention provides a directional coagulation aid block as well as an ingot furnace provided with the same. The directional coagulation aid block comprises a coagulation aid block body (10), wherein the thickness of the middle part of the coagulation aid block body (10) is greater than that of the rim. In the early and later growth periods of polycrystalline silicon, the heat conduction rate in the central part of the coagulation aid block body is consistent with that of the rim part, so that the transverse temperature gradient of the ingot furnace is reduced, and the smooth growth interface and the stable growth speed of the polycrystalline silicon are obtained.