Materials Literature
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The source characteristics of third-generation synchrotron radiation machines lead to enhanced possibilities for diffraction topographic techniques: real-time observations, high-resolution experiments, investigation of heavy or bulky materials using short wavelengths and the possibility of using large sample environme…
The elucidation of the structure of semiconductor multilayers can be adequately determined by X-ray methods but the interpretation is not always straightforward. In this paper we introduce the idea of full three-dimensional diffraction-space mapping to obtain information on the three-dimensional structure of imperfect…
X-ray projection reflection topography has been applied to a number of strongly absorbing crystals in order to find general rules for rendering dislocations visible. Single- and double-crystal schemes have been utilized. Considering direct images of dislocations and calculating the ratio of extinction to the absorptio…
Variations in the band structures of C60-polymers are studied, when pi-conjugation conditions are changed. We look at band structures in order to discuss a metal-insulator transition, using a semi-empirical model with the Su-Schrieffer-Heeger type electron-phonon interactions. We find that electronic structures change…
Self-diffusion coefficients of a series of polycyclic charged systems and their parent compounds were measured by using the PGSE NMR method. These data suggest that the dianions of naphthacene 2 and pyracylene 3 may exist as dimers with sandwich structure, just like the lithium salt of the tetraanion of corannulene 1.
The arrangement of charged and uncharged guests (N and two H2O molecules; see structure on the right) and their interaction in the cavity of the anion of the title compound 1 can be controlled by deliberately exchanging particles in the truncated cone outside the host (not shown), which resembles an ion channel. Since…
Abstract This book describes how Monte Carlo modeling methods can be applied to Electron Microscopy and Microanalysis. Computer programs for two basic types of Monte carlo simulation are developed from physical models of the electron scattering process; a Single Scattering program capable of high accuracy but requirin…
Abstract Reactive extrusion of polypropylene (PP)/natural rubber (NR) (90/10) blends was conducted in the presence of a peroxide [1,3‐bis( t ‐butylperoxy)benzene] and coagent (trimethylolpropanetriacrylate, TMPTA). Effects of peroxide and coagent content were studied in terms of melt index (MI), melt viscosity, morpho…
Abstract Introduction of amidoxime groups into cellulose substrate was investigated by reaction of cyano‐group‐containing celluloses such as cyanoethylcellulose (CE‐Cell) and acrylonitrilegrafted cellulose (G‐Cell) with hydroxylamine at 70°C in water medium (pH = 7.0). Dissolving pulp from softwood was used as the cel…
Correlations in low-frequency atomic displacements predicted by molecular dynamics simulations on the order of 1 ns are undersampled for the time scales currently accessible by the technique. This is shown with three different representations of the fluctuations in a macromolecule: the reciprocal space of crystallogra…
Analytical procedures are developed for a composite system consisting of shape memory alloy fibers within an elastic matrix subject to uniform temperature. Micromechanics for the calculation of the equivalent properties of the composite are prcscnted by extending the multi-cell model to incorporate shape memory alloy…
Ion transport mechanisms in Mg 2+ -stabilized Na + - beta ''-alumina were investigated by molecular dynamics simulations. Two compositions, different Mg 2+ distributions, and different system sizes were used in the temperature range from 200 K to 1700 K. The trajectory plots of Na + ions and the Na + -Na + radial dist…
We report optical second harmonic generation measurements in single crystal α-SiC of polytype 6H. The angular dependence of second harmonic intensity was consistent with two independent nonvanishing second order susceptibility components, as expected for a crystal with hexagonal symmetry. For the fundamental wavelengt…
Strong and stable blue photoluminescence (PL), visible to the naked eye under 0.4 μW of 300 nm and 2.7 μW of 370 nm excitation, has been observed for samples of Si clusters embedded in SiO2 matrices, prepared by rf co-sputtering followed by N2 annealing at 800 °C. Si K-edge extended x-ray absorption fine structure (EX…
The line shapes of multiplet components of the complex x-ray photoemission spectra of the Ta $4f$ core levels in $1T$- and ${4H}_{b}$-Ta${\mathrm{S}}_{2}$ are shown to have different asymmetries associated with the charge density wave induced differences in the densities of states at distinct Ta sites which produce si…
Pseudopotential models are used to study large strain, axial loading of the alkali metals. Various bcc $\phantom{\rule{0ex}{0ex}}\ensuremath{\rightleftarrows}\phantom{\rule{0ex}{0ex}}$fcc transitions are found to be associated with bifurcations from primary to secondary branch paths, under strict uniaxial load. Theore…
Cohesion properties between carbon nanotubules and potassium atoms are studied using a first-principles total-energy and band-structure approach. The present calculations which assume linearly aligned arrangements of K atoms inside and outside of tubules suggest that the classical wetting picture of capillary action i…
Erratum to Europhys. Lett. 27 (9) 661-666 (1994).
A simple, local cluster interaction is presented, which has as (only) ground states perfectly quasicrystalline tilings from a single local isomorphism class. Since these tilings do not allow for any perfect matching rules, it is thereby shown that the class of structures which are the ground state of some finite range…
The effect of phorbol ester on the synthesis of nitric oxide (NO) in murine microglial cells was examined. Phorbol 12-myristate 13-acetate (PMA), a protein kinase C (PKC) activator, alone had no effect, whereas PMA with recombinant interferon (rIFN)-gamma synergistically increased NO synthesis in murine microglial cel…