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131.
R. Ryoo S. H. Joo M. Kruk M. Jaroniec 《Advanced materials (Deerfield Beach, Fla.)》2001,13(9):677-681
Ordered mesoporous carbons have recently been synthesized using ordered mesoporous silica templates. The synthesis procedure involves infiltration of the pores of the template with appropriate carbon precursor, its carbonization, and subsequent template removal. The template needs to exhibit three‐dimensional pore structure in order to be suitable for the ordered mesoporous carbon synthesis, otherwise disordered microporous carbon is formed. MCM‐48, SBA‐1, and SBA‐15 silicas were successfully used to synthesize carbons with cubic or hexagonal frameworks, narrow mesopore size distributions, high nitrogen Brunauer–Emmett–Teller (BET) specific surface areas (up to 1800 m2 g–1), and large pore volumes. Ordered mesoporous carbons are promising in many applications, including adsorption of large molecules, chromatography, and manufacturing of electrochemical double‐layer capacitors. 相似文献
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Wang J 《Small (Weinheim an der Bergstrasse, Germany)》2005,1(11):1036-1043
This article reviews progress in the development of nanomaterials for amplified biosensing and discusses different nanomaterial-based bioamplification strategies. Signal amplification has attracted considerable attention for ultrasensitive detection of disease markers and biothreat agents. The emergence of nanotechnology is opening new horizons for highly sensitive bioaffinity and biocatalytic assays and for novel biosensor protocols that employ electronic, optical, or microgravimetric signal transduction. Nucleic acids and antibodies functionalized with metal or semiconductor nanoparticles have been employed as amplifying tags for the detection of DNA and proteins. The coupling of different nanomaterial-based amplification platforms and amplification processes dramatically enhances the intensity of the analytical signal and leads to ultrasensitive bioassays. The successful realization of the new nanoparticle-based signal amplification strategies requires proper attention to nonspecific adsorption issues. The implications of such nanoscale materials on amplified biodetection protocols and on the development of modern biosensors are discussed. 相似文献
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多孔蒸压砂砖及其制备方法,涉及建筑材料领域.所述多孔蒸压砂砖包括以下质量百分比的原料:磷石膏3％～8％、粉煤灰15％～25％、电石渣15％～25％、湿排灰5％～10％、建筑垃圾5％～15％、粗集料40％～50％.在多孔蒸压砂砖的配方中提高粗集料的比例,从而提高了多孔蒸压砂砖内部的孔隙率,在结晶失水时内部有空间释放应力,... 相似文献
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Maria Laura Martins‐Costa Rogrio M. Saldanha da Gama 《International journal for numerical methods in engineering》2001,52(10):1047-1067
This work studies an unsaturated flow of a Newtonian fluid through a rigid porous matrix, using a mixture theory approach in its modelling. The mixture consists of three overlapping continuous constituents: a solid (porous medium), a liquid (Newtonian fluid) and an inert gas (to account for the mixture compressibility). A set of two nonlinear partial differential equations describes the problem, which is approximated by means of a Glimm's scheme, combined with an operator splitting technique. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
139.
A. Stein 《Advanced materials (Deerfield Beach, Fla.)》2003,15(10):763-775
This report highlights developments in the fields of microporous and mesoporous materials that were published mostly during the year 2002. Selected examples are provided to illustrate new zeolite structures, porous coordination materials, mesoporous solids with new compositions, controlled morphologies, and increased hydrothermal and thermal stabilities, as well as porous solids with tunable pore openings or other structural features that can be dynamically modified. A number of applications are discussed, including stabilization of reactive guests, separations, electronic materials, and sensors. 相似文献
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