Materials Literature
按标题、摘要、年份、主题和来源检索公开元数据。结果保留作者、摘要、分类与原始来源链接。
A technical overview discussed the rationale for using edible films for preventing moisture loss from films while allowing permeability of oxygen and carbon dioxide to prevent anaerobic bacterial growth within the encased food. Detailed attention also is given to the characteristics of the types of edible films, cover…
The properties of various types of amorphous carbon and hydrogenated amorphous carbon are reviewed with particular emphasis on the effect of atomic structure on the electronic structure. It is shown how the proportion of sp3 and sp2 sites not only defines the short-range order but also a substantial medium-range order…
The emeraldine salt form of polyaniline, conducting in the metallic regime, can be synthesized electrochemically as a film exhibiting a well defined fibrillar morphology closely resembling that of polyacetylene. Cyclic voltammograms of chemically synthesized and electrochemically synthesized polyaniline are essentiall…
The orientational optical nonlinearity of the mesophases of liquid crystals (LCs) is attracting ever more attention, owing to the high values of the constants characterizing it, owing to the many interesting specific features that LCs introduce even into traditional nonlinear optical effects, and owing to the potentia…
Calculated volumes of formation for substitutional impurities in alkali halides are shown to be approximately consistent with the empirical rule that for miscible crystals the average volume per ion pair scales linearly between the two single-component extremes (Vegard's rule). The small deviations found from the rule…
We present the first experimental study of shear-flow--induced behavior in a two-dimensional anisotropic fluid: circular, freely suspended films of smectic-C liquid crystals. Depending on the topology of the in-plane director configuration, we observe either a phase winding state, where \ensuremath{\Phi}, the phase de…
Silver cluster ions (${\mathrm{Ag}}_{1}$${\mathrm{}}^{+}$, ${\mathrm{Ag}}_{3}$${\mathrm{}}^{+}$, ${\mathrm{Ag}}_{4}$${\mathrm{}}^{+}$, ${\mathrm{Ag}}_{5}$${\mathrm{}}^{+}$, ${\mathrm{Ag}}_{7}$${\mathrm{}}^{+}$, and ${\mathrm{Ag}}_{9}$${\mathrm{}}^{+}$) generated in a sputtering arrangement were filtered in energy sele…
Proton spin-lattice relaxation times (${T}_{1}$) measured for the first time across a random transition-metal alloy system, ${\mathrm{V}}_{\mathrm{x}}$${\mathrm{Nb}}_{1\mathrm{\ensuremath{-}}\mathrm{x}}$${\mathrm{H}}_{0.2}$, from 100 to 700 K reveal (a) a suppression of hydride phase precipitation at low temperatures…
The growth of nematic films near a wall close to the nematic-isotropic transition is studied for planar boundary conditions. If the nematic phase wets the wall, near the onset of bulk nematic behavior the nematic film near the wall is in a Kosterlitz-Thouless low-temperature phase. The transition to this phase can be…
We show that the \ensuremath{\alpha}-(AlMnSi) crystal structure is closely (and systematically) related to that of the icosahedral Al-Mn-Si alloys. Using a modification of the ``projection'' method of generating icosahedral structures from six-dimensional lattices, we find a simple description of the \ensuremath{\alph…
The dielectric permittivity and loss of 1-cyanoadamantane have been measured under isothermal conditions in the frequency range, 100-2*10 5 Hz and the temperature range, 80-350K in the glassy crystal, supercooled (metastable) and stable (disordered) crystals and partially ordered crystalline states. Two relaxation reg…
X-ray measurements performed on a variety of materials demonstrate that it is possible to observe diffuse scattering that originates in the abrupt change of density at a crystal surface. Such a discontinuity gives rise, in general, to rods of scattering in reciprocal space which are most intense close to the Bragg pea…
A model of intercalation is presented which can be used for sophisticated three-dimensional computer simulations of staging kinetics. A realistic microscopic description of the intercalation process and of the stage-3 to stage-2 transition has been obtained for the first time. Stage disorder and three-dimensional effe…
Field-assisted ion exchange has been used to extend the profile repertoire and to speed the ion exchange process for gradient-index (GRIN) applications. Profiles are predicted for various ion mobility ratios and time-varying electric fields. Profile control is demonstrated by silver for sodium exchange in an aluminosi…
A set of MS-Xα calculations on the MoFe3S4 (SH)3−6 ion is reported. Three levels of theoretical models are considered: spin-restricted, C3v symmetry, which is most easily compared with the traditional ligand-field picture; spin-polarized, C3v symmetry; and spin-polarized, Cs symmetry. An MS=3/2 ground state correspond…
The results of refractive-index measurements in ZrF4–BaF2–LaF3–AlF3 glass and the effects of the addition of NaF are described. The dispersion properties are not enhanced by the addition of NaF, as shown by increased material dispersion M at long wavelengths and decreased crossover wavelength λ0.
A model has been developed which predicts the chromatic properties of gradient-index materials based on the composition of the glass. It yields a gradient Abbe number and a gradient partial dispersion which can be used by the lens designer in the design of achromatic gradient-index lens systems. Over 100 glasses with…
Within a new theoretical approach the current and energy decay in amorphous semiconductors is studied. The relaxation of photoexcited carriers observed by transient photoconductivity experiments in amorphous silicon and chalcogenides can well be described by an algebraic power-law decay. The theoretical explanation is…
The intensity and energy shift of the Ge 3d surface core-level photoemission is determined with the use of synchrotron radiation. Cl- and Br-terminated Ge(111)?(hy(1\ifmmode\times\else\texttimes\fi{}1) surfaces are used to calibrate the absolute coverage CTHETA and to obtain accurate line shapes. We find binding-energ…
The adsorption of chlorine on Si(111)-(7\ifmmode\times\else\texttimes\fi{}7) has been studied with various photoemission techniques with the use of synchrotron radiation. At room temperature, bonding of one, two, and three chlorine atoms to a Si surface atom was observed with Si 2p core-level shifts of 930, 1830, and…