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: Disclosed is a clean method for preparing layered double hydroxides (LDHs), in which hydroxides of different metals are used as starting materials for production of LDHs by atom-economical reactions. The atom efficiency of the reaction is 100% in each case because all the atoms of the reactants are converted into the target product since only M2+(OH)2, M3+(OH)3, and CO2 or HnAn? are used, without any NaOH or other materials. Since there is no by-product, filtration or washing process is unnecessary. The consequent reduction in water consumption is also beneficial to the environment.

Abstract: This invention provides a general method for preparing a large oriented nanostructured mixed metal oxide (MMO) film comprising the steps of (a) preparing a highly (00l)-oriented LDH film, and (b) calcining the LDH film at a temperature of 300° C. to 1300° C. for 10 min to 36 h to obtain an oriented nanostructured MMO film. In the oriented MMO film, MMO nanoparticles are densely packed and form defect-free films which have high thermal stability. The major advantage of the present method is that it can be used for mass-production of large continuous oriented nanostructured MMO films without using any templates, lattice-matched single-crystalline substrates and/or expensive equipment, and the composition of the prepared MMO films can be readily adjusted by changing the composition of the LDHs fims as the precursor.

Abstract: This invention describes a nano-scale magnetic solid base catalyst and its preparation method. The catalyst involves a magnetic core coated with a solid base active layer. The synthesis of the nano-scale magnetic cores was first carried out using a rapid nucleation method in a colloid mill reactor using a liquid-liquid reaction. The nano-scale magnetic cores were mixed with a mixed salt solution. The LDH-containing magnetic cores were prepared in a colloid mill reactor by a rapid nucleation method, and subsequently calcined to give a solid base mixed oxides coated on magnetic cores. The characteristics of this catalyst are: nano-scale, high surface area and high activity and selectivity in base-catalyzed reactions. The highly dispersed catalyst can be easily reclaimed using an external magnetic field because of its magnetism. The catalyst can be utilized in base catalysis in organic reactions such as glycol ether synthesis, ester exchange, aldol condensation, etc.

Abstract: The invention describes a method of preparing magnetic ferrites from layered precursors in which Fe2+ is first introduced into the layers of layered double hydroxides (LDHs) in order to prepare Me-Fe2+—Fe3+ LDHs, and then by utilizing the easily oxidized nature of Fe2+, binary or multi-component ferrite materials containing Fe3+ in a single crystalline phase can be prepared. Values of the saturation magnetization of ferrites prepared by the method are significantly increased compared with ferrites prepared by traditional methods. Because the metal elements in the layered precursor have the characteristics of a high degree of dispersion, high activity and small particle size (average particle size 40-200 nm), no milling is required before calcination, thus simplifying the production process, shortening the production period, reducing capital investment in equipment and economizing on energy costs. In addition, the method does not corrode production equipment and does not pollute the environment.

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: A preparation method of silica, especially superfine silica, with water glass and carbon dioxide as major raw materials in a carbonization reaction conducted under a high gravity field, typically in a Higee reactor.