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。
Abstract Racemic D , L ‐lactide and meso ‐ D , L ‐lactide were polymerized with four different initiators: Al(isopropoxide) 3 , AIEt 3 /neopentyl alcohol (1 : 1, mole ratio), AIEt 3 /(+)‐menthol (1 : 1, mole ratio) and methylaumoxane. Most polymerizations were conducted in xylene at 60, 90 and 120°C, but at 60°C the y…
A kinetic analysis of densification is presented for the case of isolated, identical pores separated by dense, polyerystal‐line material where the grain size is a variable (smaller to larger, relative to the pore size). The analysis includes the influence of both grain growth and mass transport rates on the driving po…
Abstract The objective of this study is to determine the energy dissipation processes in polymer‐matrix composites during impact of ballistic projectiles. These processes include heat, fiber deformation and breakage, matrix deformation and fracture, and interfacial delamination. In this study, experimental measurement…
Two crystals of monoclinic hen egg-white lysozyme were irradiated in a monochromatic synchrotron X-ray beam (λ = 1.488 Å), the first as a rapidly frozen crystal mounted at the end of a glass fiber at low temperature (120 K) and the second mounted in a capillary tube at ambient temperature (298 K). Comparison of oscill…
Abstract Four silane coupling agents, (1H,1H,2H,2H-polyfluoroalkyl)trimethoxysilanes ((1H,1H,2H,2H-henicosafluorododecyl)trimethoxysilane, C10F21C2H4Si(OCH3)3, (1H,1H,2H,2H-heptadecafluorodecyl)trimethoxysilane, C8F17C2H4Si(OCH3)3, (1H,1H,2H,2H-tridecafluorooctyl)trimethoxysilane, C6F13C2H4Si(OCH3)3, and (1H,1H,2H,2H-…
The corrosion resistance of stainless steel weld metal in the ranges of 17 to 28% chromium (Cr), 6 to 60% nickel (Ni), 0 to 9% molybdenum (Mo), and 0.0 to 0.37% nitrogen (N) was examined. Critical pitting temperatures were determined in ferric chloride (FeCl3). Passive film breakdown potentials were assessed from pote…
High‐temperature superconductors, ferroelectric materials , electrochromic films, and semiconductors are just some of the materials which can be produced from transition‐metal alkoxides using the sol–gel method. The method itself is outlined, the control of the various parameters, such as choice of precursor and mediu…
Abstract The orientation characteristics of extruded poly(ethylene terephthalate) (homopolymer) sheets are discussed with respect to: mode of extension (simultaneous versus sequential), strain rate, stretch ratio, and temperature. The nature of the stress–strain curve recorded during the process of extension, and its…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTBroadband dielectric study on binary blends of bisphenol-A and tetramethylbisphenol-A polycarbonateG. Katana, F. Kremer, E. W. Fischer, and R. PlaetschkeCite this: Macromolecules 1993, 26, 12, 3075–3080Publication Date (Print):June 1, 1993Publication History Published online…
Thin films of aromatic polyurea were prepared by simultaneous deposition of 4,4'-diamino diphenylmethane (MDA) and 4,4'-diphenylmethane diisocyanate (MDI) on a polyimide film substrate. By changing the evaporation temperature of the monomers, the monomer molar ratio of MDA to MDI of the deposited film was varied to yi…
The reaction between nitrogen gas and an intermetallic compound is studied, with particular reference to Sm2Fe17 , treating the Sm2Fe17Ny system as a gas-solid solution. A simple lattice gas model is used to describe the reaction of nitrogen atoms with the metal lattice in terms of the net reaction energy U0=−57±5 kJ/…
A finite element model capable of simulating solidification of binary alloys and the formation of freckles is presented. It uses a single system of equations to deal with the all-liquid region, the dendritic region, and the all-solid region. The dendritic region is treated as an anisotropic porous medium. The algorith…
Abstract Differential pulse polarography (DPP) and cyclovoltammetry (CV) were conducted to study the redox behaviour of poly( p ‐phenylenevinylene) (PPV; E = 0,76 V; E = −1,74 V) as well as of three insoluble PPV‐derivatives and four soluble aryl‐substituted PPV's. Oxidation studies of DP‐PPV, DMOP‐PPV and DPOP‐PPV in…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTDynamics and phase transitions in spin-crossover complexes: x-ray structures and basic crossover phenomena in the solvate series bis(3-ethoxysalicylideneaziridinopropylaminato)iron perchlorate.solvateAndrew J. Conti, Raj K. Chadha, Kathryn M. Sena, Arnold L. Rheingold, and D…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTHydrothermal synthesis and structure of molybdoarsenate [H4AsIII2AsVMoV8MoVI4O40]-, a bicapped, reduced Keggin speciesM. Ishaque Khan, Qin Chen, and Jon ZubietaCite this: Inorg. Chem. 1993, 32, 13, 2924–2928Publication Date (Print):June 1, 1993Publication History Published o…
The temperature evolution of the lattice parameters of lead phosphate, Pb 3 (PO 4 ) 2 , indicates three lattice instabilities with anomalies near 530, 453 and ca 430 K. Only the phase transition at 453 K is ferroelastic with a spontaneous strain e=(e 1 -e 1 0 0 e 5 0). Volume anomalies occur near 530 and ca 430 K that…
The gas-phase processes relevant for oxidation during growth of YBa2Cu3O7−δ (YBCO) films by pulsed laser deposition in different oxidizing ambients are discussed using a phenomenological model. The model consists of an accounting for the neutral species generated from the target during laser ablation, and their attenu…
couples were prepared from glass starting materials with one-half of the sample enriched in r8O and the other half containing the natural abundance (-0.2 wto/o). Following exchange ofO across this diffusion couple at high temperature and pressure, '8O concentration profiles were analyzed using an ion microprobe. O dif…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTPhotoregulated binding of spiropyran-modified concanavalin A to monosaccharide-functionalized self-assembled monolayers on gold electrodesItamar Willner, Shai Rubin, and Yael CohenCite this: J. Am. Chem. Soc. 1993, 115, 11, 4937–4938Publication Date (Print):June 1, 1993Publi…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTTemkin-type model for the description of induced heterogeneity: CO adsorption on Group 4 transition metal dioxidesVera Bolis, Claudio Morterra, Bice Fubini, Piero Ugliengo, and Edoardo GarroneCite this: Langmuir 1993, 9, 6, 1521–1528Publication Date (Print):June 1, 1993Publi…