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 phase-transition behaviour of mixtures of liquid crystals (LCs) and photochromic spiropyran derivatives, induced by isomerization of the guest molecules, has been investigated. Two types of spiropyran derivatives were employed: normal spiropyrans which are stable in the closed form (spiropyran form; SPF) and open-…
In the dark, both photochromic forms of co-polymer 1 (R = H, CH3; R1 = CN, OCH3) are indefinitely stable at room temperature. In combination with their mesomorphic properties, this stability makes these materials interesting for optical information storage.
Cyclic fatigue in ceramics is reviewed, focusing on recent research. Several cyclic fatigue mechanisms hereby proposed are summarized briefly in section 3. In section 4, fatigue characteristics of all available materials are explained. Alumina, silicon nitride and lead zirconate titanate (PZT)are prone to cyclic fatig…
Tetra(N-methyl-4-pyridyl)porphyrinatoiron(III) pentachloride and its N-methyl-2-pyridyl isomer have been adsorbed onto the highly crosslinked cation ion-exchange resin Dowex MSC1 and have been used to catalyse the reaction of Z-cyclooctene with iodosylbenzene in methanol. Two oxidation products have been detected, epo…
Copper oxide was deposited on a zinc aluminate prepared from high specific area alumina and zinc nitrate. The activity of the solid obtained has been measured in the catalytic combustion of methane before and after an aging test performed at 1340 K. The environment of the copper species was followed by UV–VIS reflecta…
Molecular assemblies within Langmuir–Blodgett (LB) films of 1,4,8,11,15,18-hexaoctyl-22,25-bis(carboxypropyl)phthalocyanine (1a) copper 1,4,8,11,15,18-hexanonyl-22,25-bis(carboxypropyl)phthalocyaninate (1b) and 1,4,8,11,15,18-hexadecyl-22,25-bis(carboxypropyl)phthalocyanine (1c) have been examined using X-ray diffract…
Acid treatment of Ca2+ montmorillonite has been shown to increase significantly its effectiveness as a support for ZnCl2 Friedel–Crafts alkylation catalysts; optimum treatment conditions have been established and evidence is reported for a synergistic interaction between absorbed salt and acid-activated clay.
Previous analysis of the distribution of experimental solvent molecule positions around amino acid side chains showed that distinct clustering occurred close to polar or charged atoms in proteins. We have used those data to predict likely solvent positions around proteins not used in our initial analysis. We envisage…
Heat-capacity C(T) data on the title materials, as well as on CuO for comparison, were obtained with use of a differential scanning calorimeter to a precision of \ensuremath{\simeq}0.1--1%. The measurements were carried out (i) to characterize the thermal anomaly at the tetragonal-orthorhombic transition temperature $…
There have been a great deal of progress in the development of high performance silicon nitride and sialon ceramics, largely owing to better understandings of sintering phenomena and processing-microstructure-properties relations. In this paper, sintering mechanisms and factors affecting sintering are reviewed for the…
A direct approach to the investigation of the reflection of electromagnetic waves from a plane interface separating a vacuum half-space and a stratified anisotropic layer is presented. The formulation involves the generation of a Riccati differential equation for a certain 2*2 reflection matrix. The approach is alread…
Poly(amidoamine)s were synthesized by polyaddition reaction: to bis-acryloylpiperazine of piperazine (1), or N,N'-bis(2-hydroxyethyl)ethylenediamine (2), and to 2,2-bis(acrylamido)acetic acid of piperazine (3). Compound 2 was also end-capped with 4-hydroxythiophenol, thus introducing a terminal moiety suitable for rad…
Treatment of poly(vinylidene difluoride), PVDF, with aqueous lithium hydroxide solution results in defluorination and oxidation at the polymer surface, whereas all previously reported wet methods for surface modification of fluoropolymers have to be executed under a dry nitrogen atmosphere, this process can be perform…
Two polymorphs of the condensed species [Ti16(µ4-O)4(µ3-O)8(µ-O)4(µ-OEt)16(OEt)16] have been obtained: a monoclinic form prepared in absolute ethanol and a tetragonal one obtained from 5% aqueous ethanol. The monoclinic form (compound 1) crystallizes in the space group C2/c with a= 23.392(7), b= 19.627(8), c= 24.130(1…
The calculated hyperpolarisabilities of substituted polythiophenes, polypyrroles and polyfurans containing an electron donor at one end of the molecule and an electron attractor at the other increase slowly with increasing number of heterocyclic rings. If the effective hyperpolarisability per unit volume is considered…
X-ray photoelectron spectroscopy was used to study the reoxidation kinetics of both mechanically and chemically polished as well as freshly fractured SrTiO3 surfaces. X-ray take-off angles were varied in order to resolve surface contributions from those further into the sample. Most surfaces were found to have Sr/Ti r…
ABSTRACT Afmite-element formulation is used to obtain numerical solutions to the simultaneous moisture and heat diffusion equations describing the moisture removal and heat intake process for an isotropic sphere. The model is used to solve a sample problem of drying a soybean kernel. The distribution and gradients of…
A two-surface kinematic hardening model for the stress-strain response of metals under nonproportional tension-torsion cyclic loading is developed and verified with critical experiments. In this model, both the yield and limit surfaces are assumed to be ellipses in the two-dimensional stress plane to account for aniso…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXT"Intrinsic" response of polymer liquid crystals in photochemical phase transitionTomiki Ikeda, Takeo Sasaki, and Haeng Boo KimCite this: J. Phys. Chem. 1991, 95, 2, 509–511Publication Date (Print):January 1, 1991Publication History Published online1 May 2002Published inissue…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTSpectroscopic characterization of meso-tetrakis(1-methylpyridinium-4-yl)porphyrins, [(TMpyP)H2]4+ and [(TMpyP)M]4+, in aqueous micellar media, where M = VO2+, Cu(II), and Zn(II)Karl M. Kadish, B. G. Maiya, and C. Araullo-McAdamsCite this: J. Phys. Chem. 1991, 95, 1, 427–431P…