摘要:
Described herein is a scalable, economic, energy and time efficient method for the synthesis of a crystalline uniform nanoporous oxide material by utilizing colloidal particles in solution combustion synthesis. By removing colloids from nanocomposite via chemical etching crystalline uniform porous oxide is prepared with tailored porosity. The produced oxides have high specific surface area, high pore volume, uniform pore structure and high crystallinity. Properties of the oxide can be tuned by the concentration and size of colloids added, which affects the porous structure (mesopore diameter, pore wall thickness, surface area, and pore volume). In principle, this method can be applied to synthesize different high porosity crystalline metal oxides and nanocomposites.
摘要:
Process for the manufacture of a mesoporous product comprising the following successive steps: a) preparation of a slip comprising: a solvent, an additive, more than 4%, as percentage by volume based on the slip, of a powder formed of ceramic particles, b) oriented freezing of the slip, so as to form a block comprising ice crystals separated by walls, c) removal of the ice crystals from said frozen slip block, optionally removed from the mold, so as to obtain a porous preform, d) removal of the additive, so as to obtain a preformed mesoporous product, the additive and the amount of additive being chosen so that the additive is present in a mesopore-forming micellar phase in said walls, more than 25% by volume of said ceramic particles exhibiting a size less than twice the size of the micelles of said mesopore-forming micellar phase.
摘要:
Disclosed is a gas sensing material for methylbenzene detection. Specifically, the gas sensing material includes a nanocomposite of Cr2O3 and ZnCr2O4. The content of Cr in the nanocomposite is from 67.0 at. % to 90.0 at. %, based on the sum of the contents of Cr and Zn atoms. The gas sensing material is highly selective to methylbenzenes over other gases and is highly sensitive to methylbenzenes. Also disclosed are methods for preparing the gas sensing material. The methods facilitate control over the composition of the gas sensing material and enable rapid synthesis of the gas sensing material at low temperature. Also disclosed is a gas sensor including the gas sensing material.
摘要:
Disclosed herein is a ceramic body comprising at least one phase comprising a pseudobrookite-type crystal structure and at least one phase comprising zirconium tin titanate. Also disclosed are porous ceramic honeycomb structures comprising a ceramic body comprising at least one phase comprising a pseudobrookite-type crystal structure and at least one phase comprising zirconium tin titanate and methods of preparing a ceramic body comprising at least one phase comprising a pseudobrookite-type crystal structure and at least one phase comprising zirconium tin titanate.
摘要:
Disclosed are ceramic bodies comprised of composite cordierite aluminum magnesium titanate ceramic compositions and methods for the manufacture of same.
摘要:
The present application discloses a ceramic preform, a method of making a ceramic preform and a metal matrix composite comprising a ceramic preform. In one exemplary embodiment, the ceramic preform comprises a ceramic compound compressed into the shape of a cylinder by rotational compression molding. The cylinder has an inner surface and an outer surface. A first liner may be attached to the inner surface of the cylinder and a second liner may attached to the outer surface of the cylinder. The metal matrix composite of the present application may be formed as a brake drum or a brake disc.
摘要:
A porous ceramic honeycomb article includes a primary cordierite phase and an intercrystalline glass phase. In an as-fired condition, the porous ceramic honeycomb article exhibits microcrack parameter Nb3≦0.06 and an as-fired E500° C./E25° C. ratio ≦0.99. The article exhibits a coated microcrack parameter Nb3≦0.14 and a coated E500° C./E25° C. ratio ≦1.06 after the porous ceramic honeycomb article has been washcoated and calcined at a temperature of 550° C. After the article is exposed to a thermal treatment at a temperature ≧800° C. following washcoating and calcining, at least a first portion of the porous ceramic honeycomb article has a first treated microcrack parameter Nb3≧0.18, and a first treated mean coefficient of thermal expansion of not more than 12×10−7/° C. over a temperature range of 25° C. to 800° C. Methods of forming the porous ceramic honeycomb article are also disclosed.
摘要:
A honeycomb filter comprising a partition wall forming a plurality of flow channels, and a catalyst supported on at least a portion of the surfaces of the partition wall and/or on at least a portion of the pore interiors of the partition wall, wherein the honeycomb filter has a first end face and a second end face, the plurality of flow channels comprising a plurality of first flow channels having their ends closed on the second end face side and a plurality of second flow channels having their ends closed on the first end face side, and when the elemental composition ratio of the partition wall is represented by the following compositional formula (I): Al2(1−x)MgxTi(1+y)O5+aAl2O3+bSiO2+cNa2O+dK2O+eCaO+fSrO (I), the inequalities 0
摘要翻译:一种蜂窝过滤器,包括形成多个流动通道的分隔壁和支撑在分隔壁的表面的至少一部分上和/或分隔壁的孔内部的至少一部分上的催化剂,其中蜂窝 过滤器具有第一端面和第二端面,所述多个流动通道包括多个第一流动通道,其端部在第二端面侧封闭,并且多个第二流动通道的端部在第一端面上封闭 并且当分隔壁的元素组成比由以下组成式(I)表示时:Al 2(1-x)Mg x Ti(1 + y)O 5 + aAl 2 O 3 + bSiO 2 + cNa 2 O + d K 2 O + eCaO + fSrO ),不等式0
摘要:
Disclosed are ceramic bodies comprised of composite cordierite aluminum magnesium titanate ceramic compositions and methods for the manufacture of same.
摘要:
The invention provides superficially porous metal oxide or hybrid metal oxide monoliths with ordered pore structures. The superficially porous hybrid silica monoliths of the invention provide several major advantages over existing silica monoliths. When used in chromatography, the superficially porous hybrid silica monoliths of the invention deliver fast separation at very low back pressure and possess superb pH stability and much improved mechanical strength.