Materials Literature
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The structure and reducibility of ceria clusters was investigated using simulated annealing and interionic potentials, given by Sayle and co-workers (Sayle, T. X. T.; Parker, S. C.; Catlow, C. R. A. Surf. Sci . 1994, 316, 329), which include terms for ionic and van der Waals interactions, overlap repulsions, and ion p…
Due to its semirigid nature, electrically conductive polyaniline (PANI) has long been regarded as an intractable material, i.e. infusible and poorly soluble in organic compounds. Among the rare exceptions is camphorsulfonic acid (CSA) doped PANI, which exhibits good solubility in m -cresol, whereas for other sulfonic…
Nonequilibrium and equilibrium molecular dynamics simulations are reported for a united-atom model of n-decane at a state point in the liquid phase. The viscosity calculated by our nonequilibrium molecular dynamics simulations is in good agreement with that obtained from our equilibrium molecular dynamics simulations…
An infinite stair-like layered ferromagnetic system is obtained from the reaction of K3[CrIII(CN)6] with [NiII-(cyclam)][ClO4]2(cyclam = 1,4,8,11-tetraazacyclotetradecane); a quasi-two-dimensional magnetic behaviour is suggested by the absence of three-dimensional magnetic order down to 2 K.
In order to make a comparison between the properties of low molecular weight poly(phenyleneethynylene) type compounds and the corresponding high molecular weight polymers, we have synthesized oligomers and model molecules of poly(phenyleneethynylene) derivatives by two different routes. This paper describes the synthe…
The synthesis and excited-state dynamics are described for zinc-methylenechlorin−porphyrin−pyromellitimide triads, ZC−HP−I and ZC−ZP−I, and related dyads ZC−HP, ZC−ZP, HP−I, and ZP−I, where ZC, HP, ZP, and I indicate a zinc-methylenechlorin, a free-base porphyrin, a zinc-porphyrin, and pyromellitimide, respectively. I…
A range of mesoporous gallosilicate molecular sieves with the MCM-41 structure have been synthesized using gallium nitrate as the source of gallium and characterized in detail by elemental analysis, XRD, 71 Ga and 29 Si MAS NMR, N 2 adsorption measurements, and TEM. The quality of the products is very sensitive to the…
The resting state structure of the metallocene−alkyl cation, the coordination of the olefin to the preferred resting state structure, and the insertion process of the Ti-constrained geometry catalyst (CpSiH 2 NH)TiR + have been studied with density functional theory. A combined static and dynamic approach has been uti…
Here we describe the three-dimensional structure of 4-chlorobenzoyl-CoA dehalogenase from Pseudomonas sp. strain CBS-3. This enzyme catalyzes the hydrolysis of 4-chlorobenzoyl-CoA to 4-hydroxybenzoyl-CoA. The molecular structure of the enzyme/4-hydroxybenzoyl-CoA complex was solved by the techniques of multiple isomor…
The edge plasma, D. Reiter wall effects on particle recycling in tokamaks, J.K. Ehrenberg physical sputtering and radiation-enhanced sublimation, W. Eckstein and V. Philipps chemical erosion, E. Vietzke and A.A. Haasz electron emission from solids, J. Schou control of plasma-surface interactions by thin films, J. Wint…
A vertical gradient freeze apparatus was set up to investigate the crystal growth in high magnetic field. In the presence and absence of a magnetic field, temperature profiles were measured from solid-liquid interface to over Te-doped InSb melt, and InGaSb with low GaSb mole fraction and Te-doped InSb crystals were gr…
The magnetic and mechanical properties of 19%Co-1.9%V-0.3%Nb-Fe high strength (/spl sigma//sub y/=90 ksi) soft magnetic alloy were studied after aging at 450/spl deg/C for up to 800 h. The magnetic induction B (H/sub m/=10 and 25 Oe respectively) decreases rapidly in the first 100 h and approaches a lower limit at abo…
We examine the influence of the diverging concentration fluctuations near a spinodal on the dynamics of branched polymer solutions in the vicinity of a sol−gel transition. Dynamic light scattering (DLS) measurements on pregel solutions and gels of methyl methacrylate (MMA) cross-linked with varying amounts of ethylene…
Abstract The absence of a predetermined helical sense in the polyisocyanates causes the formation of helix reversals which enforce a strong cooperativity for the amplification of chiral effects. The helix reversals though also place a limit on this amplification, a limit which would be eliminated by reducing the helix…
Evidence has been found that solid solution of 10 mol% lead titanate in lead magnesium niobate bears strong resemblance to spin and dipolar glasses. The frequency dispersion of the temperature of the permittivity maximum, Tm, has been analyzed using the Vogel-Fulcher relationship. The difference between the solid solu…
The thermal shock fracture mechanism of metal/ceramic functionally graded materials was studied by burner heating test. Dependence of thermal shock crack initiation and propagation on controlled compositional gradients was virtually shown and discussions were made on the basis of fracture mechanics with special refere…
Three homoleptic copper(II) complexes have been prepared which feature 6-halogen-substituted 2-pyridonate ligands [{Cu2(xhp)4}n](n= 1, xhp = 6-chloro- or 6-bromo-2-pyridonate; n= 2, xhp = 6-fluoro-2-pyridonate). X-ray structural analysis of the complexes showed that for the chlorine- and bromine-substituted derivative…
Polymerization of racemic α-methyl-β-propiolactone (MPL) was carried out using Zn-, Sn-, La-, Y-. and Al-based organometallic catalysts. It was found that Zn(C 2 H 5 ) 2 /H 2 O (1/0.6), ( n C 4 H 9 ) 2 Sn(OCH 3 ) 2, Al(O i C 3 H 7 ) 3, and (C 2 H 5 ) 2 AlOC 2 H 5 produced atactic poly(α-methyl-β-propiolactone) (PMPL),…
Abstract The phase separation states of hemicellulose and lignin in their blends were investigated by means of contact angle measurements. The hysteresis behavior in dynamic contact angles suggested that a phase separation of cluster‐state type (not of random dispersion type) took place at hemicellulose‐rich and ligni…
The miscibility of the carbosilane analogue of poly(α-methylstyrene), poly(methylphenylsilylenemethylene), named poly(sila-α-methylstyrene) (PSiαMS) with an M w value of 188 000 and polystyrene (PS) having different molecular weights is investigated using DSC and cloud point measurements. The observed miscibility beha…