Materials Literature
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New general results on the self-energy of fast electrons interacting with metal surfaces are presented with emphasis on the energy-loss problem in electron microscopy. Some applications to both spherical and planar targets are considered. Our results are relevant to the understanding of inelastic electron scattering n…
The intracellular concentrations of the polypeptides encoded by the two enolase (ENO1 and ENO2) and three glyceraldehyde-3-phosphate dehydrogenase (TDH1, TDH2, and TDH3) genes were coordinately reduced more than 20-fold in a Saccharomyces cerevisiae strain carrying the gcr1-1 mutation. The steady-state concentration o…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTSpectroscopic studies of the binuclear ferrous active site of deoxyhemerythrin: coordination number and probable bridging ligands for the native and ligand-bound formsRichard C. Reem and Edward I. SolomonCite this: J. Am. Chem. Soc. 1987, 109, 4, 1216–1226Publication Date (P…
Abstract The luminescence of colloidal CdS in solutions containing sodium polyphosphate as stabilizer is activated by the addition of either Ag(ClO 4 ) or colloidal Ag 2 S. The degree of activation depends on how strongly the CdS and Ag2S particles are attached to each other, and this attachment is controlled by the c…
The authors present results obtained by 57 Fe Mossbauer spectroscopy on R 2 Fe 14 B, where R represents any of the rare earth elements except Pm, Eu and Yb. Additional measurements have been performed on oriented powder for R=Y, Pr and Ho. For the case of Y the measurements at 4.2 K were performed in applied magnetic…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTMolecular structure and magnetic properties of a novel Fe(III) tetranuclear complex containing oxo, alkoxo, and carbonato bridgesDonald L. Jameson, Chuan Liang Xie, David N. Hendrickson, Joseph A. Potenza, and Harvey J. SchugarCite this: J. Am. Chem. Soc. 1987, 109, 3, 740–7…
Abstract In the early days of electron microscopy polystyrene latex particles were used as magnification standards. But in contrast to optical diffraction grating replicas made with carbon or SiO with precise line spacings resistant to electron irradiation, the latex spheres undergo changes, and conflicting reports ha…
It is shown that a recurrence relation exists such that the resolution function and luminosity of an optical system consisting of any number of alternate collimators and reflecting crystals can be calculated analytically. Certain cases of practical interest in neutron and X-ray diffraction are evaluated explicitly usi…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTStructure of [(.eta.-C5H5)Fe(CO)2(CS)]PF6, a comparison of metal-thiocarbonyl and metal-carbonyl bondingJames W. Richardson Jr., Robert J. Angelici, and Robert A. JacobsonCite this: Inorg. Chem. 1987, 26, 3, 452–454Publication Date (Print):February 1, 1987Publication History…
Abstract Two phase transitions were located for solid [(CH3)4N]GaBr4 at 404 and 138 K. The temperature dependences of 1H NMR spin-lattice relaxation times were determined mainly at 20 MHz. A shallow 1H T1 minimum appearing at ca. 400 K and a deep one below ca. 250 K were observed. The latter minimum could be explained…
Electron microscopy of the Azotobacter vinelandii tetragonal surface array, negatively stained with ammonium molybdate in the presence of 1 mM calcium chloride, showed an apparent repeat frequency of 12 to 13 nm. Image processing showed dominant tetrad units alternating with low-contrast cruciform structures formed at…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTDiscrimination between molecular and free-radical models of 1-phenyldodecane pyrolysisPhillip E. Savage and Michael T. KleinCite this: Ind. Eng. Chem. Res. 1987, 26, 2, 374–376Publication Date (Print):February 1, 1987Publication History Published online1 May 2002Published in…
The influence of microstructural variations on the fracture toughness of two tool steels having compositions (wt-%) lC–4Cr–5Mo–2V–6W (AISI M2 high-speed steel) and 0·35C–5Cr–1·5Mo;amp;#x2013;1V (AISI H13 hot-work steel) was investigated. In the as-hardened condition, the H13 steel has a higher fracture toughness than…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTA comparison of electron donor and proton abstraction activities of thermally activated pure magnesium oxide and doped magnesium oxidesKenneth J. Klabunde and Hiromi MatsuhashiCite this: J. Am. Chem. Soc. 1987, 109, 4, 1111–1114Publication Date (Print):February 1, 1987Public…
Abstract Resonance Raman spectra (RRS) of azobenzene, 4‐aminoazobenzene, 4‐methylaminobenzene and 4‐dimethylaminoazobenzene in the solid state and in a range of solvents have been recorded. The RRS of the 4‐aminoazobenzenes are much more solvent dependent than those of azobenzene. Their electronic absorption spectra s…
Abstract The influence of composition on the primary nucleation process of poly(ethylene oxide) spherulites in the case of poly(ethylene oxide)/poly(methyl methacrylate) (PEO/PMMA) blends was investigated by optical microscopy and DSC. In the case of isothermally crystallized samples it was found that heterogeneous nu…
The electrical conductivity and dielectric loss of films of polyether ether ketone have been investigated over a wide range of frequencies and electric fields in the temperature range of 40 to 140°C. The volume resistivity of PEEK was found to be 1014 Ωm at temperatures 80°C but decreased significantly above this temp…
We incubated samples of five unfertilized Argentinian soils with phosphate at 4, 25, 40, and 60°C and measured the change in the null-point phosphate concentration through time. There was an initial decrease in this phosphate concentration, but, in some cases, it was followed by an increase in concentration. The incre…
Medium-chain S-acyl fatty acid synthetase thioester hydrolase (thioesterase II), a discrete monomeric enzyme of 29 kDa, regulates the product specificity of the de novo lipogenic systems in certain specialized mammalian and avian tissues, such as mammary and uropygial glands. The amino acid sequence of a 57-residue re…
Abstract The Raman spectrum of commercial "sulfur dichloride" shows strong lines due to SCl 2 and S 2 Cl 2 and weak Cl 2 lines at 25 °C, but strong SCl 2 and SCl 4 signals at -100 °C (the latter are superimposed on the S 2 Cl 2 lines). Thus, the intense Raman effect of SCl 4 can be used to detect small amounts of chlo…