Materials Literature
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The freezing of 1:1 mixtures of hard spheres is studied using density functional theory. Three different stable solid phases are found: a disordered (phase separated) fcc structure and ordered CsCl and NaCl structures. The relative stability of these phases is predicted as a function of the ratio of the diameters of t…
A simple electron-phonon coupling model is constructed for the layered-metal oxides. The predictions of the model are the tetragonal-to-orthorhombic instability and separately from it, the bond dimerization within the layers. High T c in those materials is associated with the soft shear phonon branch in their tetragon…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTNMR properties of the complexes trans-[M(.eta.2-H2)(H)(PEt2CH2CH2PEt2)2]+ (M = Fe, Ru, Os). Intramolecular exchange of atoms between .eta.2-dihydrogen and hydride ligandsMaria Bautista, Kelly A. Earl, Robert H. Morris, and Andrea SellaCite this: J. Am. Chem. Soc. 1987, 109,…
A variety of inorganic solids have been prepared in recent years by employing a wide range of conditions such as irradiation by laser or electron beams, use of high pressures, high vacuum, or hydrothermal conditions, rapid quenching of melts, melting in a watercooled copper container using rf power (skull melting) or…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTTetratellurafulvalene(TTeF)Richard D. McCullough, Gaik B. Kok, Knud A. Lerstrup, and Dwaine O. CowanCite this: J. Am. Chem. Soc. 1987, 109, 13, 4115–4116Publication Date (Print):June 1, 1987Publication History Published online1 May 2002Published inissue 1 June 1987https://pu…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTStructure of the hydrated electronH. F. Hameka, G. W. Robinson, and C. J. MarsdenCite this: J. Phys. Chem. 1987, 91, 12, 3150–3157Publication Date (Print):June 1, 1987Publication History Published online1 May 2002Published inissue 1 June 1987https://pubs.acs.org/doi/10.1021/…
Abstract The structure and synthesis of some poly(vinylsaccharide)s is described. Five different monomers, N ‐saccharide‐substituted acryl‐and methacrylamides, were prepared and polymerized to high molecular weight products using different initiator systems. The influence of the chemical structure of the saccharide mo…
High-resolution neutron and X-ray diffraction data for vitamin B~2 coenzyme have been obtained with the objective of elucidating the water organization in this crystalline system. Here, details of the data collection and refinement of the individual models are described. Neutron data: Mr = 1939 (assuming exchange of 1…
The fracture initiation and arrest stress intensity factors were determined for a SiC‐whisker‐reinforced AI 2 O 3 matrix composite. A chevron‐notched, three‐point‐bend specimen was used to genera e the load/displacement curve, which exhibited repeated crack initiation, followed by crack arrest behavior. Corresponding…
Abstract Aromatic polyesters and polyamides with disc‐like mesogens in the main chain were prepared from tetra‐substituted hydroquinones and derivatives of 1,4‐phenylenediamine. Depending on the atomatic acids (terephthalic acid, 2,5‐dialkoxyterephthalic acid) used in the condensation reaction, the repeating units of…
A procedure was developed to purify large quantities of PII protein from an Escherichia coli strain which contains a multicopy plasmid harboring the structural gene of PII (the glnB gene). Ultraviolet spectra of uridylylated and unuridylylated PII were obtained using the purified PII and empirical formulas to calculat…
Large area chemical vapour deposition of diamond has been obtained using magneto-microwave plasma. The important point of the developed system is to set the electron cyclotron resonance condition (875 G), where the highest plasma density is expected, at the deposition area by controlling the distribution of an applied…
The infrared spectra of several type Ia diamond crystals expected to contain voidites have been examined in the wavenumber range 4000–2700 cm−1. The absence of any absorption which could possibly be attributable to the stretching of N─H bonds makes unlikely recent suggestions that the voidites may contain a solid phas…
Abstract Versuche, von Dimethylphenyl‐2‐tolylsilan ( 5 ) oder 2‐Brombenzoesäure ausgehend über 2‐(Dimethylphenylsilyl)benzoylchlorid ( 11a ) mit Zinntetrachlorid als Ringschlußkatalysator zu 9,9‐Dimethyl‐9‐sila‐10(9 H )‐anthracenon ( 4a ) zu gelangen, führten stets in hohen Ausbeuten zur Titelverbindung 14a , deren Ko…
Abstract Five paraffins (C30–C44) and three linear compounds with polar end-groups, such as hydroxyl, methyl-ester, and carboxyl groups, were deposited on the cleavage surface of an alkali halide crystal in vacuo. Paraffin films deposited on the substrate took the same crystal structure and molecular orientation, inde…
A b initio crystal orbital calculations on the oxidized form of polyaniline with alternating benzoid–quinoid structure are reported. For two possible configurations, the trans and the cis isomer, the twist angle between nearest neighbor rings is optimized with respect to the total energy per elementary cell. It turns…
The structure of the omega-phase which is formed by the quenching of Ti-14 wt%Mo alloy from 1223 K to 273 K was investigated at the atomic level using a high-resolution electron microscope (HREM). The HREM image were formed by using 15 diffracted waves including diffuse scattering due to the omega-phase. The focus of…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTThermochemistry of inorganic solids. 7. Empirical relations among enthalpies of formation of halidesMohamed W. M. Hisham and Sidney W. BensonCite this: J. Phys. Chem. 1987, 91, 13, 3631–3637Publication Date (Print):June 1, 1987Publication History Published online1 May 2002Pu…
A design is given for a powder diffractometer on a synchrotron source. A reasonable balance between resolution and luminosity is achieved by making the effective mosaic spread parameters of the monochromator and analyser crystal equal to the vertical divergence of the synchrotron beam. A monochromator with a Bragg ang…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTTemperature-dependent changes in the structure of the amorphous domains of semicrystalline polymersMarc L. MansfieldCite this: Macromolecules 1987, 20, 6, 1384–1393Publication Date (Print):June 1, 1987Publication History Published online1 May 2002Published inissue 1 June 198…