Materials Literature
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Magnetic entropy change (ΔS) of a single crystal Ni50.1Mn20.7Ga29.6 alloy under different applied fields has been investigated near the martensitic–austenitic structural transition temperature of 219 K. With increasing applied field from 0.2 to 5 T, the sign of ΔS changes from positive to negative. At 0.8 T the positi…
The compound Cs10.5[(V16O40)(Si4.5V1.5O10)].3.5H2O is the first example of an extended structure in which a polyoxometallate anion is linked by an extended tetrahedral unit.
A real-space method is developed to calculate molecular hyperpolarizabilities in the time-dependent density functional theory. The method is based on the response function formalism which was developed by Senatore and Subbaswamy for the third harmonic generation of rare-gas atoms [Phys. Rev. A 35, 2440 (1987)]. The re…
Transmission electron microscopy and high resolution x-ray diffraction are used to characterize defects in ZnO layers grown by plasma-assisted molecular-beam epitaxy on (0001) sapphire. Two- and three-dimensional types of growth modes are described and the observed mosaic structure is analyzed in each case. It is foun…
Mesoporous silica materials have been synthesised in strongly acidic media at pH = 1.3 using high concentrations of a non-ionic surfactant (Brij 76) as a structure-directing agent. Well-defined ordered mesoporous silicas with hexagonal (HI), lamellar (L∞) and solid phase (S) structure have been prepared at room temper…
Single crystals have been grown in the (Bi1/2Na1/2)1−xBaxZryTi1−yO3 perovskite system by a self-flux method over the range of compositions y=0.04 and x=0.06–0.012. Rhombohedral (x⩽0.08) and tetragonal phase (x⩾0.09) crystals have been obtained that do not show polarization or field-induced strain hysteresis characteri…
A photoluminescence (PL) band, the M band, was observed in photoluminescence spectra for various excitation densities in high-quality ZnO epitaxial thin films. The M band intensity increased superlinearly with an increase in the excitation intensity, suggesting that the observed PL band is due to a biexciton state. In…
A convergent synthesis employing porphyrin building blocks has afforded dendrimeric multiporphyrin arrays containing n Zn-porphyrins (n = 4, 8, or 20) and one free base- (Fb-) porphyrin joined via diarylethyne linkers. Size exclusion chromatography was used extensively for purification. The arrays have sufficient solu…
Abstract In this article, we review the progress made in the area of industrial twisted fibrous structures. First, we focus on the general geometrical description of the structures, and then move to issues including the tensile behavior and fracture process. The effects of fiber bending and torsion, strain rate, and v…
A comparative study of the third-order nonlinear optical properties, via the newly developed heterodyned optical Kerr effect (OHD-OKE) measurements, of silver phenylacetylide and related compounds is reported. [AgC[triple bond]CC(6)H(5)](n) (1) was found to exhibit efficient third-order nonlinear optical susceptibilit…
Abstract As‐manufactured polymeric fibers are oriented semi‐crystalline structures in which the macromolecules are rarely in their equilibrium state. Further instabilities are imparted when the fibers are converted to yarns and the yarns to fabrics. Heat setting is an important industrial process, since it rids them o…
Abstract Continous filament nonwovens are fabrics produced by the direct lay processes, wherein webs are made directly from fibers as they are being spun from molten plastics. These processes eliminate intermediate steps in the production of fabrics, and they provide opportunities for increasing production and cost re…
Tungsten oxide (WO3) thin films were deposited by spray pyrolysis of an ammonium tungsten oxide solution. The effect of postannealing on the structural, transport and optical properties of the films has been studied. Under steady-state illumination, slow photoconductivity growth and relaxation transients were observed…
Sugar-appended azonaphthol derivatives 1 possessing an aromatic hydroxyl group and 2 possessing the n -butanoyloxy group were synthesized and proved to be capable of gelating water/ethanol mixtures. Gels formed by gelator 1 displayed different morphologies depending on the gelator concentration. The aqueous gel formed…
The addition of silicon to hydrogenated amorphous carbon can have the advantageous effect of lowering the compressive stress, improving the thermal stability of its hydrogen, and maintaining a low friction coefficient up to high humidity. Most experiments to date have been on hydrogenated amorphous carbon–silicon allo…
During film growth by a variety of techniques, intrinsic tensile stresses can be created by the coalescence of neighboring islands. Experimental results with diamond films produced by chemical vapor deposition are compared with a relatively simple model to demonstrate that a realistic interpretation of these coalescen…
Indium oxide (InOx) films with a thickness of 10–1100 nm were deposited onto Corning 7059 glass and silica substrates at various substrate temperatures. An unusual decrease of the lateral grain size with increasing substrate temperature during deposition was found. The changes in the conductivity of the films after ex…
N 2 O decomposition catalyzed by oxidized Fe clusters localized in the micropores of Fe/ZSM-5 has been studied using the DFT approach and a binuclear cluster model of the active site. Three different reaction routes were found, depending on temperature and water pressure. The results show that below 200 °C the binucle…
Using numerical simulation techniques, the transmission and reflection coefficients, or S parameters, for left-handed metamaterials are calculated. Metamaterials consist of a lattice of conducting, nonmagnetic elements that can be described by an effective magnetic permeability μeff and an effective electrical permitt…
A novel core-shell gold colloid-silk fibroin (SF) bioconjugate was prepared by the protein in situ redox technique at room temperature, in which the tyrosine (Tyr) residue of the SF, having strong electron donating properties, in situ reduced Au(III) ions to Au colloids showing a stable and highly monodispersed nature.