Materials Literature
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By a numerical relaxation scheme we have simulated the plastic deformation of a quasicrystal. Shear stress was applied to a quasiperiodic icosahedral atomic configuration of Lennard-Jones particles, and nucleation of dislocation dipoles was observed which move in a slip plane. We also found climb motion and dissociati…
Abstract The effects of reaction time (2 to 72 h) and NH 4 + /A1 3+ molar ratio (1.6, 2.4 and 3.2) on the hydrothermal synthesis of ammonium-saponites are investigated. The gels are obtained by mixing powders, resulting in a stoichiometric composition, Mg 3 Si 34 Al 0.6 O 10 (OH) 2 , with aqueous ammonium solutions, w…
We report the first success in the preparation of transparent TS-1 zeolite film on a micro slide glass using nanosized TS-1 zeolite crystals (<100 nm). The nanosized TS-1 zeolite was crystallized at 80 °C and 1 atm. We intentionally controlled the zeolite particle size by using mild synthetic conditions and particle m…
Prior investigations have shown that polypyrrole has low gas-transport selectivity. This has been attributed to the microporous morphology obtained when thin films of this polymer are prepared by conventional synthetic methods. In this paper we show that polypyrrole with a dense (as opposed to microporous) morphology…
Quantum chemical ab initio calculations for two ternary thioferrate crystals, Na5FeS4 and Na3FeS3, have been performed. Using a cluster model approach with 250 optimized point charges for the single well-isolated complexes [FeS4]5− and [Fe2S6]6−, the electronic and magnetic properties are investigated. In particular,…
Samples with one or both ends of monodisperse poly(ethylene oxide) (PEO) functionalized with perfluorodecanoyl groups (PEO F or PEO 2F ) were synthesized and blends of these end-capped PEOs with PEOs of the same molecular weight ( M n ∼2000 to ∼16 000 K) were prepared as cast films. As-cast and annealed samples were a…
Thin, c-\ensuremath{\rightarrow}-axis oriented films of the magnetic perovskite ${\mathrm{Pr}}_{0.5}$${\mathrm{Sr}}_{0.5}$${\mathrm{MnO}}_{3}$ were prepared by dc-magnetron sputtering, structurally characterized by x-ray diffraction and their physical properties investigated by magnetization and electrical transport m…
In‐situ crack‐propagation experiments, in conjunction with thermochemical experiments, have been used to examine the role of discontinuous interphases on the fracture behavior of solid‐state diffusion‐bonded Cu/α‐Al 2 O 3 couples. Clean, interphase‐free interfaces exhibit crack extension by brittle decohesion at the c…
Semifluorinated n -alkanes, F 3 C(CF 2 ) m -1 (CH 2 ) n -1 CH 3 (for short, F m H n ) are short-chain diblock copolymers that show interesting properties when dissolved in nonaqueous media. Due to the high incompatibility between fluorocarbons and hydrocarbons that produces strong immiscibility between fluorocarbons a…
Abstract Processing and compatibilization effects on the phase morphology and the tensile behavior of blends of polystyrene and high‐density polyethylene (PS/HDPE) were investigated. As predicted by theory, high shear rates encountered during extrusion blending led to efficient minor phase emulsification in immiscible…
A study of the Raman spectra of BaTiO 3 -SrTiO 3 solid solutions has yielded information on the dependence of phonon mode frequencies on component concentration. The contribution to the dependences by the change in lattice volume through the Grüneisen coefficients, and the term connected directly with the solid soluti…
The nucleation and growth of octacalcium phosphate (Ca 4 H(PO 4 ) 3 ·2.5H 2 O, OCP) on titanium oxide (TiO 2 ) particles have been investigated using constant composition (CC) methods in aqueous solution at 37 °C. The solid phases during the reaction were examined by X-ray diffraction, scanning electron microscopy (SE…
The temperature dependence of the spin-lattice relaxation times (${\mathrm{T}}_{1}$ ) of $^{23}$ Na and $^{11}$ B nuclides has been studied in a number of Na-borate and -germanate glasses and liquids in order to understand the effects of the type of network, concentration of the modifying cation, and network former-mo…
An achiral semiperfluorinated chain has been introduced into classical phenyl benzoate mesogenic moieties in which the other terminal chain is chiral. The consequences of this modification on the mesomorphic properties are discussed. At a low fluorination extent, the smectic A phase is strongly favoured, while at high…
The effects of niobium doping on the hysteresis parameters of sol—gel Pb 1.1−(x/2) (Zr 0.53 Ti 0.47 ) 1−x Nb x O 3 (0, x, 0.05) have been reported for two sets of films with analogous grain size and degree of (111) texture but with different surface microstructures. For both sets, a strong continuous decay of the remn…
We review the effects of scattering-interference of the primary, exciting beam on the electron emission from ordered atomic arrays. The yield of elastically and inelastically backscattered electrons, Auger electrons and secondary electrons shows a marked dependence on the incidence angle of primary electrons. Both the…
Copolymers containing vinylpyrrolidone and mono and dialkyl itaconate units with different length in the side chains were synthesized and characterized. Copolymers of vinylpyrrolidone with three different compositions of monomethyl, monoethyl, monopropyl, monoamyl, dimethyl, diethyl, dipropyl, and diamyl itaconate wer…
The spreading of n -octane droplet at the surface of sodium chloride aqueous solutions was investigated as a function of the salt concentration in a saturated closed cell. As long as the salt concentration is lower than 1.2 M, the macroscopic drop takes the form of a lens in a stable coexistence with its adsorbed thin…
The syntheses of the first dimeric donors ( 19a − c ) derived from TTF with p -quinodimethane structures as well as the analogues dimeric acceptors ( 20, 21 ) derived from TCNQ and DCNQI have been carried out from the novel 2,2‘-oxydianthraquinone ( 18 ). Depending upon the substitution pattern on the 1,3-dithiole rin…
We have determined relative affinities of type I and type II human non-epidermal cytokeratin (CK) polypeptides synthesized in Escherichia coli from cDNA, using the method of surface plasmon resonance, and have compared the influence of ionic strength and ion quality on the assembly to intermediate filaments (IFs) by v…