7results about How to "Particle size adjustable" patented technology

The invention belongs to the field of semiconductor materials, and discloses gallium oxide and a synthesis method thereof. The synthesis method comprises the following steps: introducing ammonia water into a gallium nitrate solution, and continuously stirring to obtain a white turbid liquid; aging the white turbid liquid, filtering and washing to obtain an intermediate product; and calcining the intermediate product to obtain solid particles which are gallium oxide. According to the synthesis method, gallium nitrate and ammonia water are used as core raw materials, additional additives and complex precursors are not needed, the impurity introduction risk can be greatly reduced, and the high purity of the product can be guaranteed by combining washing and calcining procedures; meanwhile, the process steps are simple, the operation conditions are mild and controllable, expensive special equipment is not needed, the production cost is low, the method is suitable for large-scale production, and a gallium oxide product with good dispersity and high crystallinity can be obtained after a precursor prepared through a precipitation method is calcined and crushed.

The utility model discloses a kind of multi-particle size adjustable medicinal excipient granulator, including granulating cylinder, fixedly connected with fixed granulating net in the side edge opening of granulating cylinder, the inside of the lateral wall of granulating cylinder is equipped with receiving groove, two layers of movable granulating net are slidably connected with the inside receiving of receiving groove, the surface of granulating cylinder is provided with limit sliding slot below movable granulating net, the above of granulating cylinder is equipped with feeding cylinder;The utility model is by being provided with fixed granulating net and two layers of movable granulating net in the side edge of granulating cylinder, the size of aperture is continuously regulated using the overlapping cooperation of movable granulating net and fixed granulating net, and multiple-particle size requirement can be flexibly adapted.The design breaks through the limitation of traditional single screen mesh corresponding single particle size, reaches adjustable particle size by pure mechanical structure, does not need to replace granulating net during shutdown, significantly improves regulation efficiency and production continuity.

The application belongs to the technical field of olefin polymerization, and discloses a fluorine aryl borate compound dispersion system, a preparation method and application thereof, the preparation method comprising the following steps: 1) dissolving the fluorine aryl borate compound in a good solvent to prepare a saturated solution; 2) under the action of stirring and ultrasonic, the saturated solution is added into a poor solvent, and after the addition is completed, the stirring and ultrasonic continue for 3-10 minutes; 3) the suspension obtained in the step 2) is filtered to obtain a solid, the solid is dried by blowing hot nitrogen gas under stirring, and then the solid is treated at high temperature under reduced pressure; 4) the solid obtained in the step 3) is dispersed in an alkane solvent to obtain the fluorine aryl borate compound dispersion system. The preparation method has low process cost, and the particle size of the fluorine aryl borate compound in the prepared dispersion system is adjustable and the purity is improved.

The present application relates to the field of polyolefin catalysts, in particular to a Ziegler-Natta catalyst for olefin polymerization and in-situ grafting, and a preparation method and application thereof. The Ziegler-Natta catalyst comprises the following blending components and / or reaction products: a carrier, a titanium element source, a magnesium element source, an electron donor and a free radical initiator. The free radical initiator is introduced during the preparation process of the catalyst, the preparation process is relatively simple, the grafting of the polar monomer on the polyethylene is initiated, the grafting reaction is more uniform, the amount of the free radical initiator is less, the grafting efficiency is higher, and the gel content is lower; the particle size of the catalyst can be adjusted according to the use requirement, thereby the particle size of the polymer is controlled, and the grafting efficiency is improved; the grafted polyethylene can be directly obtained by using the catalyst through a one-step method, the grafted product does not need to be dried and separated, and the preparation process of the grafted polyethylene is simplified.

The application discloses a cobalt-iron catalyst and a preparation method and application thereof. The cobalt-iron catalyst is composed of iron elements, cobalt elements, metal element A and metal element B; the metal element A is at least one selected from Mn, Cu, Zn, Ti, Al, Cr, Ni, Ce and Zr; the metal element B is at least one selected from Li, Na, K, Rb, Cs, Be, Mg, Ca, Sr and Ba; in the cobalt-iron catalyst, the metal elements exist in the form of elements, oxidation states or carbonization states; in the cobalt-iron catalyst, taking the total mass of the metal elements as 100 wt%, the content of the iron elements is 30-99 wt%, the content of the cobalt elements is 30-99 wt%, the content of the metal element A is 0.1-60 wt%, and the content of the metal element B is 0.01-50 wt%.

The invention discloses a supported metallocene catalyst for ethylene polymerization and application of the supported metallocene catalyst. The supported metallocene catalyst comprises an alkyl tin chloride / methylaluminoxane / silica gel carrier and a metallocene compound supported on the carrier; the alkyl tin chloride / methylaluminoxane / silica gel carrier is a silica gel carrier modified by alkyl tin chloride and methylaluminoxane. Alkyl tin chloride is used for modifying a silica gel carrier, the compound can react with hydroxyl, and a large amount of hydroxyl is eliminated; and the metallocene can be combined with MAO, so that certain space barrier exists between the MAO and the surface of the silica gel, the crowding effect is weakened, the loading capacity is improved, and metallocene combination sites are increased.

The invention discloses a cobalt-based catalyst and a preparation method and application thereof. Comprising a cobalt element and an alkali metal element; the cobalt element exists in the form of a simple substance, cobalt oxide or cobalt carbide; the alkali metal element is selected from at least one of Li, Na, K, Rb and Cs; the alkali metal element exists in the form of a simple substance; in the cobalt-based catalyst, the total mass of the metal elements is 100 wt%, the content of the cobalt element is 50-99.5 wt%, and the balance is alkali metal elements. The catalyst has high activity and oxygen-containing compound selectivity in Fischer-Tropsch synthesis. The phenomenon of low selectivity of the oxygen-containing compound in Fischer-Tropsch synthesis is effectively solved, and an effective way is provided for improving the selectivity of the oxygen-containing compound.