Materials Literature
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The crystalline modifications of carbon described in the literature are briefly reviewed. The publications in which new types of structures, differing from the diamond and graphite lattices, are proposed and discussed are analysed in detail. The geometrical-topological characteristics of the hypothetical modifications…
The authors report infrared and Raman spectroscopic investigations of single crystals of tris-sarcosine calcium chloride (TSCC), of the isomorphous tris-sarcosine calcium bromide (TSCB) and of mixed crystals with different chlorine-bromine concentration ratios x (for TSCC 1-x B x ) in the whole wavenumber region below…
The authors present evidence for the existence of a phase transition observed at 282K on warming in 1T-TaS 2 , through differential scanning calorimetry, in-plane electrical resistivity and Hall coefficient measurements. Some in-plane anisotropy is revealed, indicating that this transition may be mainly, though not wh…
Energy-dispersive x-ray diffraction studies have been made on BaTe to 410 kbar. It undergoes a first-order phase transition from the sodium chloride structure to the cesium chloride structure at 48 kbar. $P(V)$ data were obtained over the entire range. Optical studies indicated by extrapolation that metallization will…
This book is intended to fiber technologists, textile dealers, and textile salesmen a practical guideline to become acquainted with and to deepen their knowledge of the processes for the manufacture of film tapes, split-film yarns, and fibrillated film fibers.
The excited atom model using Delta SCF Hartree-Fock calculations is tested on Mg metal. It is found that the valence configurations of the ground, one- and two-core-hole states may be unambiguously determined simply from the values of the atom-metal XPS and Auger shifts. The above state energies suggest 3s 1 3p 1 , 3s…
The magnetic and crystallographic properties of several intermetallic compounds of Gd and Pd are studied and compared with the magnetic and crystallographic properties of the corresponding ternary hydrides obtained after charging with hydrogen gas. The mean magnetic coupling strength in the various intermetallic compo…
The electrooptic coefficients ra = r33 − (n2/n3)3 r23, rb = r33, − (n1/n3)3 r13 and rc = r13 − (n2/n1)3 r23, of Rb,ZnCl4 for light propagation directions along the three crystallographic axes a, b, and c are measured in the temperature range from 100 to 220 K (ni, i = 1, 2, 3, indices of refraction). In the incommensu…
High-pressure studies have shown that $\mathrm{K}{\mathrm{Ta}}_{1\ensuremath{-}x}{\mathrm{Nb}}_{x}{\mathrm{O}}_{3}$ crystals with small $x(\ensuremath{\approx}0.02)$ exhibit relaxational glasslike behavior rather than a static ferroelectric structural phase transition as previously thought. The results show a pressure…
The magnetic phase diagram for the system CoxNi1−xMnGe (0 ≦ x ≦ 1.0) is determined by ac susceptibility measurements under pressure up to 1.5 GPa. The temperature of the magnetic phase transition behaves similarly for all compounds examined: increasing external pressure causes the Néel or Curie temperatures to increas…
High-precision measurements of the in-plane resistivity of graphite have been made in a dilution refrigerator down to 20 mK. Below 5 K, the resistivity varies as a quadratic function of temperature, behavior consistent with the electron-hole scattering mechanism. The strength of the interaction is in good agreement wi…
Existing data on Na-rare gas and rare gas–rare gas dimer potentials have been used in a computer program to simulate the formation of trapping sites for Na atoms isolated in Ar and Xe solids. The dimer potentials have also been employed to calculate the matrix perturbed energy-level structure of the Na atoms to obtain…
X-ray diffraction and Rutherford backscattering (RBS) analysis were used independently to investigate the interface reaction of Cu-Al thin-film bilayers during in situ annealing in the temperature range 157–220 °C. The growth kinetics of the θ-CuAl2 phase were measured and were found to follow a diffusion limited proc…
Diffraction properties of dielectric surface-relief gratings were investigated by solving Maxwell’s equations numerically using the differential method. The diffraction efficiency of a grating with a groove depth about twice as deep as the grating period is comparable with the efficiency of a volume phase grating. Die…
Explicit solutions for the Brazovskii-Kirova continuum model of cis-polyacetylene are presented for the following three configurations: two polarons, two bipolarons, and a polaron and a bipolaron coexisting on a single chain. The results show that two polarons attract each other with a long-range potential reflecting…
A relatively simple technique has been developed to calibrate particle- and droplet-sizing instruments manufactured by Malvern and other similar Fraunhofer diffraction particle-sizing instruments. Measurements of standard reticles using an instrument calibrated in this manner demonstrate the effectiveness of the proce…
In light of new experimental observations, a mechanism for the photogeneration of charge carriers in trans-polyacetylene is presented. By way of introduction, we discuss the qualitative changes in the picture of charged-solition photogeneration that are expected due to the inclusion of electron correlation effects. In…
Above a few hundred eV kinetic energy, Auger electrons and photoelectrons exhibit strong forward scattering by overlying atoms, and this produces intensity peaks at polar and azimuthal angles corresponding to internuclear axes. This provides a new structural probe which is especially useful for studying epitaxy, surfa…
High resolution core level photoemission spectroscopy has been used to obtain the first direct identification of the chemical species remaining on silicon surfaces after exposure to fluorine. Both Si(111) 2×1 and Si(111) 7×7 were exposed to fluorine via the dissociative chemisorption of XeF2. For fluorine coverages in…
We discuss two mechanisms proposed to explain dc switching of a bistable liquid-crystal boundary layer display. These are (1) biasing by double layer fields that arise from charge of one sign preferentially adsorbed at the walls, and (2) asymmetry in the transient depletion layer fields which result from a difference…