36results about How to "Effective particle size control" patented technology

The invention discloses a full-thin film silicon semiconductor double-electrode unbiased photocatalytic system for fully decomposing water to produce hydrogen and its application. The system includes a photoanode, a photocathode, an electrolyte, a light source, and an electrolytic cell. The structure of the photoanode Substrate layer, n / i / p structure single-node silicon thin film, oxide thin film, the structure of the photocathode is substrate layer, p / i / n structure single-node silicon thin film, hydrogen-producing metal nanoparticles, For the first time, a silicon thin-film electrode combined with a catalyst to form a full-thin film silicon semiconductor two-electrode system has achieved an unbiased full water splitting efficiency of 0.92%, which provides hope and a strategy for realizing large-scale sustainable solar hydrogen production.

The invention discloses a method for preparing nano aluminum oxide powder by an electrochemical method. In the method, aluminum is electrolyzed, and then the electrolysis product is subjected to washing, hydro-thermal treatment, washing, drying and calcining to obtain the10-90nm aluminum oxide powder. According to the invention, effective control on the particle size of aluminum oxide is realized by adjusting the current, voltage and pH and adopting the hydro-thermal treatment technology. The preparation technology of the nano aluminum oxide powder prepared by the method disclosed by the invention is simple, the production period is short, the yield is high, the product stability is good, and environmental pollution is avoided. Through the invention, the prepared nano aluminum oxide powder is widely applied to multiple fields of military industry, automobiles, metallurgy, chemical industry, ceramics and the like.

The invention belongs to the technical field of zeolite molecular sieve synthesis, in particular to a method for synthesizing needle-shaped ZSM-5 molecular sieves with controllable particle size. Zeolite particle size and morphology are important factors affecting the catalytic performance of molecular sieves. In the present invention, the particle size of the zeolite can be effectively controlled by simply adjusting the degree of polymerization of the silicon source and the aluminum source, and the mixed template agent is used, and at the same time, the zeolite with the needle shape can be obtained. The synthesis steps of the method are very simple and very easy for industrialization. Sample XRD and SEM showed that the change of silicon polymerization degree can effectively control the particle size of zeolite.

The present invention discloses a preparation method for cubic precipitated calcium carbonate. The method comprises the following processes: transporting refined and aged lime cream into a carbonation bubbling reactor with stirring, injecting purified and cooled limekiln gas to carry out carbonation reaction, when pH of the reaction mixture drops to 7.0, stopping the carbonation reaction, and controlling specific surface area (BET) of the finished calcium carbonate between 20-35 m<2> / g. Adding accelerating curing agent, heating to performing curing, maintaining the temperature between 60-90 DEG C for 2-15 hours, adding a surface treating agent, stirring the materials for 60 minutes to obtain a slurry of calcium carbonate, and subjecting the slurry to pressure filtration for dewatering, drying and pulverizing to obtain the calcium carbonate product. Compared with traditional heating curing methods, the present method has a higher curing efficiency, and obtains large cubic precipitated calcium carbonate particles in short time; size control and pH value control are more effective and more stable; the processed are simple and feasible, the costs are low, and economic effectiveness is good.

The invention discloses equipment for preparing nano powder by an electrical explosion method, and belongs to the field of nanomaterial preparation. The equipment aims at solving the problem that the conventional nano powder production equipment has a strict requirement for an insulating structure and an insulating material of a high-voltage part. The equipment comprises a nano powder reaction mechanism, an electrical explosion generation mechanism, a wire feeding mechanism matched with the nano powder reaction mechanism, an air cooler, a first connecting tube, a first insulating tube, a second connecting tube, a second insulating tube and a third connecting tube. According to the equipment, instant high voltage is generated by electrodes, so that materials in an explosion reaction cavity react to generate corresponding nano particles. Due to an improvement of a structure, the working voltage of the equipment is equal to or lower than 25KV, and a high-voltage part has a very low requirement for a high-voltage structure and a withstand voltage material. In addition, raw materials of the equipment are filamentary materials and non-insulators, so that the equipment has the characteristics of wide raw material source and high adaptability, and has good universality for various filamentary non-insulator materials.