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Structure of the amorphous phase in crystallizable polymers: poly(ethylene terephthalate)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTStructure of the amorphous phase in crystallizable polymers: poly(ethylene terephthalate)N. S. Murthy, S. T. Correale, and H. MinorCite this: Macromolecules 1991, 24, 5, 1185–1189Publication Date (Print):March 1, 1991Publication History Published online1 May 2002Published in…

Viscoelastic behavior of lightly sulfonated polystyrene ionomers

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTViscoelastic behavior of lightly sulfonated polystyrene ionomersR. A. Weiss, J. J. Fitzgerald, and D. KimCite this: Macromolecules 1991, 24, 5, 1071–1076Publication Date (Print):March 1, 1991Publication History Published online1 May 2002Published inissue 1 March 1991https://…

Textured ZnO Thin Films for Solar Cells Grown by Metalorganic Chemical Vapor Deposition

Textured ZnO films have been grown by metalorganic chemical vapor deposition (MOCVD) using diethylzinc (DEZ) and H 2 O as reactant gases. It was found that the surface morphology of films was strongly dependent on the substrate temperature. For the low substrate temperature of 150°C, the surface consists of uniformly…

Binary blends of poly(ether ether ketone) and poly(ether imide): miscibility, crystallization behavior and semicrystalline morphology

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTBinary blends of poly(ether ether ketone) and poly(ether imide): miscibility, crystallization behavior and semicrystalline morphologyG. Crevecoeur and G. GroeninckxCite this: Macromolecules 1991, 24, 5, 1190–1195Publication Date (Print):March 1, 1991Publication History Publi…

The effect of carbonate contaminations on the XPS O 1s band structure in metal oxides

Abstract The aim of the paper is to give examples of XPS analysis, showing how O 1s bands can be affected by surface carbonates. A proper peak assignment (e.g. to O − OH − species) needs the preliminary determination of a carbonate contribution. Although the samples examined represent Co and La compounds only, the pri…

Raman spectra of graphite as indicators of degree of metamorphism

This study demonstrates the usefulness of Raman microspectroscopy an evaluation of the crystallinity of graphite in natural samples. The sensitivity obtained is at least as good as that for X-ray diffractometry. Laser Raman microprobe analyses of graphite separates, mostly from suites of regionally metamorphosed carbo…

Pyramid-array surface-relief structures producing antireflection index matching on optical surfaces

Surface-relief structures having the form of an array of modified pyramids (having curved rather than flat triangular shown to produce an index-matching layer that will reduce surface reflection by several orders of sides) are Such structures are equivalent to a quintic (fifth-order polynomial) gradient-index layer, w…

Characterization of Terfenol-D for magnetostrictive transducers

Measurements were made of the piezomagnetic d33 coefficient, the free permeability, μ33T, and the open-circuit elastic compliance coefficient, s33H, of grain-oriented Terfenol-D, Tb0.3Dy0.7Fe1.93, produced by a modified Bridgman technique. Prestress levels to 9500 psi (65 MPa) and magnetic bias fields up to 2200 Oe (1…

.alpha.'-Sialon ceramics: a review

a' -Sialon ceramics promise the possibility of a reduction of the amount of glassy grain boundary phases by incorporating the oxides, present in the starting mixture as either sintering additives or impurities, into its rmallattice. It has been shown that techniques such as gas pressure sintering can be used successfu…

X-ray spectroscopic studies of nickel complexes, with application to the structure of nickel sites in hydrogenases

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTX-ray spectroscopic studies of nickel complexes, with application to the structure of nickel sites in hydrogenasesGerard J. Colpas, Michael J. Maroney, Csaba Bagyinka, Manoj Kumar, William S. Willis, Steven L. Suib, Pradip K. Mascharak, and Narayan BaidyaCite this: Inorg. Ch…

Crystal structure of stereocomplex of poly(L-lactide) and poly(D-lactide)

An equimolar mixture of poly(L-lactide) and poly(D-lactide) was crystallized into a stereocomplex whose crystal system is triclinic (P1) with cell dimensions: a = 0.916 nm, b = 0.916 nra, c (chain axis) = 0.870 nm, α = 109.2°, β - 109.2°, and γ = 109.8°. In the unit cell, a poly(L-lactide) segment and a poly (D-lactid…

Computer Programs for Standardless Quantitative Analysis of Minerals Using the Full Powder Diffraction Profile

Abstract A Fortran 77 computer program has been developed for the quantitative analysis of minerals by multiphase profile analysis of the complete powder diffraction pattern. Featured are full-matrix least-squares refinement of 14 Rietveld “instrumental parameters” (phase scales, asymmetry, preferred orientations (Mar…

Effect of sulfonic acid group on polyaniline backbone

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTEffect of sulfonic acid group on polyaniline backboneJiang Yue, Zhao H. Wang, Keith R. Cromack, Arthur J. Epstein, and Alan G. MacDiarmidCite this: J. Am. Chem. Soc. 1991, 113, 7, 2665–2671Publication Date (Print):March 1, 1991Publication History Published online1 May 2002Pu…

Gelcasting of Alumina

Gelcasting is a novel method for molding ceramic powder based on a synthesis of concepts derived from traditional ceramics and polymer chemistry. Gelcasting of alumina is described in this paper. The process is based on the in situ polymerization of acrylamide monomers as the setting mechanism for forming the green bo…

Surface effects and anchoring in liquid crystals

As their name indicates, liquid crystals simultaneously exhibit some characteristics common to both ordinary isotropic liquids and solid crystals. This ambivalence is also found in the effects of surfaces on these systems which lead to a great diversity of phenomena. These phenomena are reviewed focusing on nematic li…

Organic Solar Cells

Review: The conversion of sunlight into electricity can be achieved using a solar cell and is one of the most attractive future soruce of energy. Silicon‐based cells, while quite efficient, are difficult and expensive to produce, a fact that drives up the cost of electricity produced using them. The alternative, organ…

Rapid-phase transitions of GeTe-Sb2Te3 pseudobinary amorphous thin films for an optical disk memory

Amorphous films having a component of the stoichiometric GeTe-Sb2Te3 pseudobinary alloy system, GeSb2Te4 or Ge2Sb2Te5 representatively, were found to have featuring characteristics for optical memory material presenting a large optical change and enabling high-speed one-beam data rewriting. The material films being sa…

Transient plane source techniques for thermal conductivity and thermal diffusivity measurements of solid materials

The general theory of the transient plane source (TPS) technique is outlined in some details with approximations for the two experimental arrangements that may be referred to as ‘‘hot square’’ and ‘‘hot disk.’’ Experimental arrangements and measurements on two materials, Cecorite 130P and Corning 9606 Pyroceram, using…