Abstract: The invention provides CaCO3/SiO2.nH2O nanocomposite particles and method of producing the same. A template nucleus is used calcium carbonate and the surface of nucleus is encapsulated by a SiO2.nH2O nanolayer. The invention also provides a CaCO3/SiO2.nH2O nanocomposite particles having hollow structure, in which n=0-2. The nanocomposite particles according to the invention have a number of uses.

Abstract: The invention provides CaCO3/SiO2·nH2O nanocomposite particles and method of producing the same. A template nucleus is used calcium carbonate and the surface of nucleus is encapsulated by a SiO2·nH2O nanolayer. The invention also provides a CaCO3/SiO2·nH2O nanocomposite particles having hollow structure, in which n=0-2. The nanocomposite particles according to the invention have a number of uses.

Abstract: A process of making dispersant-coated carbon particles comprising the steps of providing a liquid mixture comprising carbon particles and a dispersant, and imparting a shear force to the liquid mixture to thereby form said dispersant-coated carbon particles.

Abstract: A process for preparing perovskite-type compound Ax(BO3)y powders involving reacting a solution containing A and a solution containing B, or a combined solution comprising A and B, with an alkaline solution in a high-gravity reactor at a temperature ranging from about 60° C. to about 100° C. A is one or more metal elements selected from the group consisting of Li, Na, K, Mg, Ca, Sr, Ba, Pb, Sm, La, Nd, Bi, and other rare-earth metal elements. B is one or more metal elements selected from the group consisting of Ti, Zr, Sn, Hf, Nb, Ce, Al, Zn, Mn, Co, Ni, Fe, Cr, Y, Sc, W, Ta, and the like. The resulting mixture is then filtered, rinsed and dried to obtain the desired powders.

Abstract: A novel process for the preparation of amorphous cefuroxime axetil particles and the amorphous cefuroxime axetil particles therefrom are disclosed in the invention. Specifically, the invention is implemented by means of antisolvent recrystallization to prepare the cefuroxime axetil in an amorphous form; particularly, the amorphous ultrafine or even nanosized cefuroxime axetil with a controllable particle size and a narrow particle size distribution. The cefuroxime axetil according to the invention can used to enhance bioavailability, since it is in an amorphous form and has a controllable particle size and a narrow particle size distribution.

Abstract: A hollow-structured mesoporous silica material composed of hollow silica particles that have a shell having radial-arrayed channels, and a process for its preparation. The thin-shell type of mesoporous materials with different morphologies are prepared by growing and synthesizing mesoporous silica on the surface of calcium carbonate nanoparticles with different shapes as inorganic templates, and then removing the inorganic templates. The hollow-structure mesoporous silica material can be used in many fields such as the preparation of catalyst, pesticide and optical fiber.

Abstract: This invention provides a process for preparing a strontium titanate powder, which comprises reacting a solution containing Ti4+ or a solution containing Sr2+, or a mixed solution containing Ti4+ and Sr2+ with an alkali solution in a high gravity reactor at a temperature of from about 60° C. to about 100° C. The strontium titanate powder prepared according to the process of the present invention has a small average particle size, narrow size distribution, integrated crystal form, and spheric form. It can be used as a raw material for dielectric, piezoelectric, resistant, sensitive ceramics and other ceramics. Furthermore, the process of the invention for preparing a strontium titanate powder in the high gravity reactor can be used for the continuous preparation of strontium titanate powder.

Abstract: A method of preparing ultrafine modified aluminum hydroxide, having two steps: a carbon component decomposition under ultra gravity conditions in a rotating bed, and a modifying treatment. The carbon component decomposition is carried out in porous packing layer inside of a rotating bed, where the mass transfer for the reaction and micro-mixing process are extremely enhanced. The aluminum hydroxide solution (as a precipitate or a dry powder) obtained is further converted by the subsequent modified treatment process. This method can control the particle size of the modified aluminum hydroxide crystal grains, homogenize its distribution, and shorten the reaction time. Particularly, the modified treatment greatly improves its weight loss temperature and weight loss ratio. The use field of the resulting aluminum hydroxide as a flame retardant and other is expanded. The average size of modified aluminum hydroxide grain obtained is from 50 nm to several micrometers, and can be controlled.

Abstract: The invention provides CaCO3/SiO2.nH2O nanocomposite particles and method of producing the same. A template nucleus is used calcium carbonate and the surface of nucleus is encapsulated by a SiO2.nH2O nanolayer. The invention also provides a CaCO3/SiO2.nH2O nanocomposite particles having hollow structure, in which n=0-2. The nanocomposite particles according to the invention have a number of uses.

Abstract: The present invention relates to a titanocene complex and a catalyst comprising the same and an alkylaluminoxane for preparing syndiotactic polystyrene. The catalyst is applicable to the industrial production of the syndiotactic polymerization of styrene. The titanocene complex has a general formula of R1Ti(OR2R3)3, where R1 is Cp or Cp containing 1-5 C1-4 alkyls, R2 is an aryl containing 6-12 carbon atoms, R3 is a halogen, OR2R3 is a halogenated aryloxy ligand.

Abstract: The invention relates to a process for the preparation of fine barium titanate (BaTiO3) powders. The process comprises introducing an aqueous solution (I) containing salts of barium and titanium, and an aqueous basic solution (II) containing an inorganic or organic base separately and simultaneously into a high-gravity reactor with the high-gravity level of 1.25G to 12,500G and performing the reaction of the solution (I) with the solution (II) at a temperature of from 60 to 100° C. The solution (I) is preheated to a temperature ranging from 60° C. to 65° C. and the solution (II) is preheated to a temperature ranging from 60° C. to 100° C. respectively prior to the reaction, in which the Ba/Ti molar ratio in the solution (I) is more than 1 and the concentration of the base in the solution (II) is such that the reaction mixture is maintained at a constant OH? concentration, preferably a pH value of about 14.

Abstract: This invention relates to calcium carbonate of different shapes including spindle, petal, whisker, needle, flake, ball and fiber. The calcium carbonate of such different shapes has an average particle size in the range of 10 nm-2.5 &mgr;m. This invention also relates to a process for preparing the said calcium carbonate with a controllable range of average particle size and different shapes. Precipitated powder of calcium carbonate with a desired shape and a controllable average particle size is obtained by carbonizing a suspension of calcium hydroxide and a feed gas containing carbon dioxide on a revolving bed under the gravitational field, and optionally in the presence of a crystal form-controller and/or crystal seeds. The precipitated powder of calcium carbonate obtained by the process according to this invention has a controllable average particle size and a narrow particle distribution.

Abstract: The present invention relates to titanocene complexes and their catalysts for preparing syndiotactic polystyrene, mainly solving the problem in the prior arts that the catalytic efficiency is not high and therefore the compound is difficult to meet the need of the industry when used for the syndiotactic polymerization of styrene. The present invention has better solved this problem and is applicable to the industrial production of the syndiotactic polymerization of styrene by adopting the technical solution of using titanocene complexes with a general formula R1Ti(OR2R3)3 as a main catalyst, where R1 is cyclopentadienyl or cyclopentadienyl containing 1-5 C1-4 alkyls, R2 is an aryl containing 6-12 carbon atoms, R3 is a halogen, and there is an oxygen atom between Ti and R2 to connect them, and constituting a catalyst with alkylaluminoxyl or/and triisobutylaluminum.