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。
Quasielastic neutron scattering measures ia a very direct way the decay of density correlations in the time range psec … nsec and on length scales of the order of ångströms. It seems therefore ideally suited to directly observe the critical dynamics predicted by the mode coupling theory of the glass transition. We rev…
A simple synthetic method for preparing aragonite whiskers has been developed. A suspension of CaCl 2 ‐MgCl 2 ‐Mg(OH) 2 with pH ∼9 has been prepared by adding Ca(OH) 2 to MgCl 2 aqueous solution. CaCO 3 whiskers (aragonite phase) have been prepared easily by blowing CO 2 ‐containing gas into the suspension. The whiske…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTAppraisal of Chemical Bond Making, Bond Breaking, and Electron Transfer in Solution in the Light of the Principle of Maximum HardnessPratim K. Chattaraj, Andres Cedillo, Robert G. Parr, and Edward M. ArnettCite this: J. Org. Chem. 1995, 60, 15, 4707–4714Publication Date (Pri…
Lead titanate sols were prepared by a sol‐gel method from lead acetate trihydrate, Pb(OOCCH 3 ) 2 3H 2 O, and titanium di‐isopropoxide bis‐acetylacetonate, Ti (OC 3 H 7 ) 2 ‐ (CH 3 COCHCOCH 3 ) 2 , in 1,3‐propanediol, HO(CH 2 ) 3 OH, as solvent. IR analysis and NMR spectroscopic techniques were used to study the react…
Abstract Sophisticated methods have been put forward in the literature to calculate Debye temperatures from the elastic constants c ik . As a simple alternative method for cubic crystals, a relation is often used that correlates Debye temperature and bulk modulus (c 11 + 2c 12 )/3 by a square‐root law. It is shown tha…
Abstract In the first part of this series of papers, the tensile properties of microcellular foams of polystyrene (PS), styrene‐acrylonitrile copolymer (SAN), and polycarbonate (PC) were reported. In this part, the impact properties of unnotched, sharply and bluntly notched samples of microcellularly foamed PS and SAN…
Abstract The hydrothermal metamorphism of a sequence of Pliocene‐aged seamount extrusive and volcanoclastic rocks on La Palma includes a relatively complete low‐ P‐T facies series encompassing the zeolite, prehnite‐pumpellyite, and greenschist facies. The observed mineral zonations imply metamorphic gradients of 200–3…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTDNA-tentacle porphyrin interactions: AT over GC selectivity exhibited by an outside binding self-stacking porphyrinNancy E. Mukundan, Gabor Petho, Dabney W. Dixon, and Luigi G. MarzilliCite this: Inorg. Chem. 1995, 34, 14, 3677–3687Publication Date (Print):July 1, 1995Public…
The subject contrast of bony anatomy in megavoltage medical radiographs is very low, making detection of bony landmarks difficult if additional noise sources are introduced into the images. One source of noise, which is inherent to the x-ray detection process, is x-ray energy absorption noise. X-ray energy absorption…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTInfluence of the Chain Length and Surface Density on the Conformation and Mobility of n-Alkyl Ligands Chemically Immobilized onto a Silica SurfaceIrene. Yarovsky, Marie-Isabel. Aguilar, and Milton T. W. HearnCite this: Anal. Chem. 1995, 67, 13, 2145–2153Publication Date (Pri…
Abstract Poly(( R )‐3‐hydroxybutyrate), P(3HB), is produced by Alcaligenes eutrophus from fructose or butyric acid. The kinetics and mechanism of P(3HB) biosynthesis are presented. Four types of copolymers, poly(3‐hydroxybutyrate‐ co ‐3‐hydroxyvalerate), poly (3‐hydroxybutyrate‐ co ‐3‐hydroxypropionate), poly (3‐hydro…
Control of microstructure in the Al 2 O 3 /LaAl 11 O 18 system was performed. Elongated alumina grains were formed by doping with small addition of silica, and 20 vol% lanthana‐ luminate was formed in situ by the reaction of LaAlO 3 ‐ A1 2 O 3 in an alumina matrix. Strengths of over 600 MPa and a high fracture toughne…
Epitaxial thin films of Al‐doped zinc oxide have been grown on sapphire substrates by pulsed laser ablation. The effect of substrate temperature, background pressure of oxygen, and substrate orientation (A, M, R, C) on the orientation relationships between ZnO and sapphire have been evaluated using on‐ and off‐axis X‐…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTDynamics of Porphyrin Molecules in Micelles. Picosecond Time-Resolved Fluorescence Anisotropy StudiesNakul C. Maiti, Shyamalava Mazumdar, and N. PeriasamyCite this: J. Phys. Chem. 1995, 99, 27, 10708–10715Publication Date (Print):July 1, 1995Publication History Published onl…
Abstract The striking photoluminescent properties of porous silicon nanostructures have received intense study since 1990. This literature review focuses on the large number of models proposed to account for efficient light emission. Two distinct luminescence bands in the visible spectral range have received most stud…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTUnsymmetrically Substituted Phthalocyanine Derivatives via a Modified Ring Enlargement Reaction of Unsubstituted SubphthalocyanineA. Weitemeyer, H. Kliesch, and D. WoehrleCite this: J. Org. Chem. 1995, 60, 15, 4900–4904Publication Date (Print):July 1, 1995Publication History…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTDonor-Embedded Nonlinear Optical Side Chain Polyimides Containing No Flexible Tether: Materials of Exceptional Thermal Stability for Electrooptic ApplicationsR. D. Miller, D. M. Burland, M. Jurich, V. Y. Lee, C. R. Moylan, J. I. Thackara, R. J. Twieg, T. Verbiest, and W. Vol…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTX-ray crystallographic studies of engineered hydrogen bond networks in a protein-zinc binding siteCharles A. Lesburg and David W. ChristiansonCite this: J. Am. Chem. Soc. 1995, 117, 26, 6838–6844Publication Date (Print):July 1, 1995Publication History Published online1 May 2…
Tetrahedral amorphous carbon (ta-C) is a dense form of amorphous carbon with a structure consisting of a highly tetrahedral bonding network. Approximately 20% of the atoms in ta-C are ${\mathit{sp}}^{2}$ hybridized and the presence of these sites plays an important role in the electrical and optical properties of the…
Recent experiments on suspensions of particles with steeply repulsive interactions are reviewed. These suspensions show the equilibrium freezing-melting transition and a glass transition similar to those obtained in computer simulations of the hard sphere system. The glass transition is identified, firstly, by the ces…