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。
The dielectric behavior of the antiferroelectric liquid crystal (R)-1-methyl- heptyl-4-( 4 ′′ -n-dodecyloxybiphenyl- 4 ′ carbonoyloxy)-3-fluorobenzoate was investigated by dielectric spectroscopy. In the antiferroelectric SmC A * phase three dielectric active processes were detected. At least one of them, the process…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTEffect of Ionic Chain Polydispersity on the Size of Spherical Ionic Microdomains in Diblock IonomersDiep Nguyen, Xing-Fu Zhong, Claudine E. Williams, and Adi EisenbergCite this: Macromolecules 1994, 27, 18, 5173–5181Publication Date (Print):August 1, 1994Publication History…
A symmetric diblock ethylene-propylene copolymer (DEP) was synthesized through hydrogenation of an anionically polymerized polybutadiene-poly(2-methyl-1,3-pentadiene) diblock copolymer (PBDb-PMPD).IR and NMR measurements showed the hydrogenation to be more than 98% complete.The resultant diblock copolymer consists of…
Experiments involving the solidification of a Pb-19 percent Sn alloy in an axisymmetric, annular mold of stainless steel are performed, and results are compared with numerical predictions. Agreement between measured and predicted cooling curves is reasonable, although undercooling and recalescence, which occur in the…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTMetalloporphyrin .pi.-Cation Radicals. Molecular Structure and Spin Coupling in a Vanadyl Octaethylporphyrinate Derivative. An Unexpected Spin Coupling PathCharles E. Schulz, Hungsun Song, Young Ja Lee, Jalal U. Mondal, K. Mohanrao, Christopher A. Reed, F. Ann Walker, and W.…
A two-dimensional Monte Carlo simulation algorithm is formulated following the tunneling mechanism for localized (pitting) corrosion. Depending on the values of a minimum set of control parameters, easily interpreted in terms of physicochemical variables, the two limiting regimes of stable and unstable corrosion are r…
The influence of temperature and time of austempering on a nodular cast iron austenitised for 30 min at 900°C has been investigated using optical and transmission electron microscopy. The carbon content of the austenite has been evaluated by measuring the lattice parameter via X -ray diffraction. The structure consist…
To improve surface hemocompatibility on cellulose hollow fibers for hemodialysis, newly designed hemocompatible polymers with a phospholipid polar group, 2-methacryloyloxyethyl phosphorylcholine (MPC) polymers, were introduced on the surface through two different methods: direct grafting of MPC on the surface, or coat…
Glasses of the (65−x)PbO⋅xPbX2⋅35B2O3 system (where X=F, Cl, Br, and I) have been made and investigated by Raman measurements. Three low frequency bands with high Raman intensities have been observed at about 40, 105, and 135 cm−1, respectively. It is found that the intensities of the depolarized low frequency Raman c…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTSingle-Component Donor-Acceptor Organic Semiconductors Derived from TCNQPaloma Bando, Nazario Martin, Jose L. Segura, Carlos Seoane, Enrique Orti, Pedro M. Viruela, Rafael Viruela, Armando Albert, and Felix H. CanoCite this: J. Org. Chem. 1994, 59, 16, 4618–4629Publication D…
Abstract The comparative interaction of Mg 2+ and Ca 2+ counterions on carboxyl groups of polygalacturonic acid is developed. Ultracentrifugation, conductimetry, potentiometry, and CD were used in this work. Evidence is provided for a simple electrostatic interaction of Mg 2+ counterions; on the opposite side, coopera…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTsyn-Oxidative Polycyclization of Hydroxy Polyenes: A New Approach to Polyether SynthesisFrank E. McDonald and Timothy B. TowneCite this: J. Am. Chem. Soc. 1994, 116, 17, 7921–7922Publication Date (Print):August 1, 1994Publication History Published online1 May 2002Published i…
Simulated high burnup UO2 and (U, Gd)O2 pellets, doped with soluble fission product elements (Sr, Zr, Y, La, Ce, Nd), were prepared. Pellet thermal diffusivities were measured by a laser flash method and their thermal conductivities were evaluated. Thermal conductivities decreased with an increase in the total amount…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTProperties and Molecular Structures of Osmium(II) Porphyrin Carbene Complexes: (5,10,15,20-tetra-p-tolylporphyrinato)osmium Di-p-tolylmethylidene and (5,10,15,20-tetra-p-tolylporphyrinato)osmium (Trimethylsilyl)methylideneJean-Pierre Djukic, Daniel A. Smith, Victor G. Jr. Yo…
The structure of liquid water in contact with a planar wall is calculated for the central force model by which water is modeled as a stoichiometric mixture of partially charged hydrogen and oxygen atoms interacting via effective spherical pair potentials. The density profiles near the wall are obtained from the Werthe…
The genus Dickieia is re-established for Navicula ulvacea, N. subinflata and N. expecta. Dickieia cells contain one complex chloroplast per cell; this consists of two ‘K’-shaped halves, linked by an isthmus containing the single discoid pyrenoid. The pyrenoid lies near one side of the girdle at the centre, while the n…
Lead zinc niobate [PZN: Pb(Zn1/3Nb2/3)O3] and compositions in the PZN-PbTiO3 system are promising materials for capacitors and actuators because of their high dielectric constant and excellent electrostrictive properties in single crystal form. PZN is one of the few relaxor ferroelectrics with high Curie temperature o…
The aim of this study was to investigate the effects of ultrasound irradiation on a biodegradable drug delivery system. Microporous, disk-shaped specimens of a 50-50% copolymer of polylactic and polyglycolic acids were gel cast from an acetone solution. A protein was incorporated in these specimens, which were then im…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTTrivanadium Polyoxoanion Chemistry. Part 4. Synthesis, Isolation, and Spectroscopic Characterization of Trivanadium Polyoxoanion-Supported (C5H5)Ti3+: (Bu4N)4[CpTi.cntdot.SiW9V3O40] and (Bu4N)6[CpTi.cntdot.P2W15V3O62]Brian M. Rapko, Matthias Pohl, and Richard G. FinkeCite th…
We investigate the efficiency of two recently introduced hybrid Monte Carlo algorithms for the off-lattice simulation of dense polymer melts. Their performance is assessed both with respect to the molecular dynamics method and new single-chain Monte Carlo techniques proposed recently. Our findings show that the long-t…