Materials Literature
按标题、摘要、年份、主题和来源检索公开元数据。结果保留作者、摘要、分类与原始来源链接。
Reaction of silica, montmorillonite and polystyrene bearing amino functions with several polyhalogenated metalloporphyrins gave an easy one-step access to new supported catalysts, owing to a selective nucleophilic substitution of the para-halogen atoms of the porphyrin meso-aryl groups by the polymer amine function; t…
The barium titanates BaTiO3, Ba2TiO4, BaTi2O5 and BaTi4O9 can be synthesized by a sol–gel method at low temperatures. The reaction between barium acetate solutions and titanium(IV) isopropoxide leads to the formation of barium titanate gels. The gels can be converted to the barium titanates by drying and calcination.…
A new, better method of producing cotton covered/polyester staple-core yarn on a modified ring spinning frame is described. The method uses the concept of twisting a “sandwich” formed by two drafted strands of cotton (rovings) on the outside and a drafted strand of polyester on the inside, thus using a total of three…
The shapes of 112 Co(II)O 6 polyhedra in 72 crystal structures of inorganic compounds were analyzed in this study. Most of these polyhedra are significantly distorted from the ideal octahedral symmetry m 3 m , observed point symmetries of the Co(II) sites are: 1(34%); [unk](29%); 2(14%); m (7%); 2/ m , 3(4%); [unk] m…
Rhodesite from Zeilberg, Unterfranken, Germany ( Z ), from Trinity County, California, USA ( TC ), and from San Venanzo, Rieti, Italy ( SV ), is orthorhombic with space group Pmam . Crystallographic data, given in the order ( Z ), ( TC ), ( SV ), are: a 0 = 23.416(5)/23.444(5)/23.428(20) Å, b 0 = 6.555(1)/6.553(1)/6.5…
The adsorption of No2 on anatase and deuteroxylated TiO2 is investigated by IR spectroscopy. It is established that NO2 reacts with the surface hydroxyl (deuteroxyl) groups of anatase to give nitrates and water molecules (H2O, HOD and D2O) weakly bonded to the nitrates, while on the surface Lewis acidic–basic pairs of…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTSurface-enhanced Raman spectra and gas chemisorption of Langmuir-Blodgett layers of lutetium and ytterbium diphthalocyaninesR. E. Clavijo, D. Battisti, R. Aroca, G. J. Kovacs, and C. A. JenningsCite this: Langmuir 1992, 8, 1, 113–117Publication Date (Print):January 1, 1992Pu…
The evolution of a Spanish montmorillonite with acid treatment has been studied. With a high concentration of acid, 8 mol dm–3 HCl, there is a break in the normal tendency of the observed behaviour. The silica created at the beginning of the reaction protects the clay structure and impedes subsequent attack. This pass…
The first edition of this highly successful text aimed, 'to deal with the basic principles of materials science in a simply yet meaningful manner'. The second edition broadened the scope to incorporat
This book is split into two sections; the first covers the characterisation of polymer molecules with respect to chemical composition, configuration and molecular mass, while the second and larger section is a thorough discussion of polymer morphology and the techniques used in its investigation.Each chapter of the bo…
Treatment of fluorinated ethylene propylene (FEP) and polytetrafluoroethylene (PTFE) by plasmas established in water vapour or ammonia gas enabled the rapid and facile modification of their surface chemistries. Under comparable plasma conditions, ammonia plasma exposures produced considerably lower air/water contact a…
A simple method to determine the fluorescence quantum yield (ϕF) of dyes adsorbed on microcrystalline cellulose is presented. The method is based on corrected fluorescence emission spectra and can easily be applied provided the energy profile of excitation is accurately determined. The quantitative determination of ϕF…
Crystals of 1,4,8,11,15,18,22,25-octahexylphthalocyanine are composed of tilted stacks of molecules with an unexpectedly large separation between the aromatic cores.
Fracture toughness behavior, stress–strain behavior, and flaw resistance of pressureless‐sintered Si 3 N 4 ‐BN ceramics are investigated. The results are discussed with respect to the reported thermal shock behavior of these composites. Although the materials behave linear‐elastic and exhibit no R ‐curve behavior, the…
Si3N4 matrix composites with dispersed SiC particles were prepared by hot-pressing compacts of powder mixtures of sub-micron size SiC and Si3N4 particles. SiC particles in nano-meter scale were dispersed uniformly inside Si3N4 grains. After adding SiC particles, the configuration of β-Si3N4 grains changed from equiaxe…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTSelective coloration of spiro pyridopyrans for guanosine derivativesMasahiko Inouye, Kwangshik Kim, and Teijiro KitaoCite this: J. Am. Chem. Soc. 1992, 114, 2, 778–780Publication Date (Print):January 1, 1992Publication History Published online1 May 2002Published inissue 1 Ja…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTGas transport properties of liquid crystalline poly(p-phenyleneterephthalamide)D. H. Weinkauf, H. D. Kim, and D. R. PaulCite this: Macromolecules 1992, 25, 2, 788–796Publication Date (Print):January 1, 1992Publication History Published online1 May 2002Published inissue 1 Jan…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTApplication of the molecular simulation technique to characterize the structure and properties of an aromatic polysulfone system. 2. Mechanical and thermal propertiesCun Feng Fan and Shaw Ling HsuCite this: Macromolecules 1992, 25, 1, 266–270Publication Date (Print):January…
Surface modification of two Teflon polymers, PFA (tetrafluoroethylene and perfluoroalkoxyvinyl ether copolymer) and PTFE (polytetrafluoroethylene), induced by argon plasma treatment using a radio frequency generator and subsequent air exposure has been investigated by x-ray photoelectron spectroscopy (XPS) and electro…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTPhotochemistry of squaraine dyes. 1. Excited singlet, triplet, and redox states of bis[4-(dimethylamino)phenyl]squaraine and bis[4-(dimethylamino)-2-hydroxyphenyl]squarainePrashant V. Kamat, Suresh Das, K. George Thomas, and Manapurathu V. GeorgeCite this: J. Phys. Chem. 199…