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。
In this third paper of a series, the influence of phonons upon the angle-resolved spectra of electrons photoemitted from the bulk bands of solids is considered. When a tight-binding formalism is used to describe the electronic states of solids, it is possible to divide the electron-phonon interaction into terms that m…
We have measured the dielectric constants of cyanobiphenyls (CB), cyanophenylcyclohexanes (PCH), and cyanocyclohexylcyclohexanes (CCH) using a capacitance bridge with a dielectric cell having a guard ring. The ratio Δχ/Δε was also measured for these materials using a new technique which is applicable when Δχ is small…
We have detected intrinsic surface phonons in amorphous silica by performing Raman scattering and infrared-reflectivity measurements on samples of porous Vycor glass. Qualitative agreement of our experimental spectra with theoretical calculations provides an identification of the surface features in terms of microscop…
The effect of the white noise on the hydrodynamic transitions is studied in the nematic MBBA. The values of both transition points to the laminar flow and to the turbulent flow increase with the amplitude of the white noise. Brief discussion is described.
Specific-heat measurements near the nematic-smectic-$A$ transitions of the octyloxy, nonyloxy, and decyloxy members of the 4-$n$-pentyl-phenylthiol-4\ensuremath{'}-alkoxybenzoate ($\overline{n}\mathrm{S}5$) homologous series reveal the presence of critical-tricritical crossover behavior upon increasing $\overline{n}$,…
Abstract A preliminary analysis of deconvolution of a nylon model is given. This is then developed to give the available deconvolution strain in cotton. The total extension is then given by adding the fibrillar strain and is compared with experimental values of breaking extension. The relation between convolution exte…
The phase diagram of Cu 2-δ Te (δ<0.22, T <400°C) is constructed with the help of the galvanic cell Cu|CuBr|Cu 2-δ Te|C, showing that it includes as large as 10 phases in the range concerned. This diagram has been justified by DTA measurements. The electronic conductivity and ionic one are also measured.
Magnetization measurements and 55 Mn NMR study of a system with the nominal formula LaNi 1- x Mn x O 3 (0.0 ≤ x ≤0.5) were made. It was found that materials with 0.03 ≤ x ≤0.5 are mixtures of a Pauli paramagnet LaNiO 3 and a ferromagnet LaNi 0.5 Mn 0.5 O 3 . The Curie temperature of LaNi 0.5 Mn 0.5 O 3 was found to be…
Auger-electron spectroscopy (AES), low-energy-electron diffraction (LEED), electron-energy-loss spectroscopy (ELS), and ultraviolet-photoelectron spectroscopy (UPS) were used to characterize the composition, structure, and electronic properties of the strontium-titanate (100) surface and the platinum---strontium-titan…
New progress in Mie theory calculations is reported. A computer program is available using the Lentz algorithm allowing more extensive calculations, namely, studying of bigger diameters and more important absorption coefficients. Emphasis on particle sizing is considered.
A first order phase transition occurs at Ni (111) surfaces under conditions of controlled chemical potential. For a dilute Ni–C alloy of fixed bulk composition an abrupt change occurs (as temperature is lowered) in the surface carbon coverage from a very low coverage state to a two dimensional crystalline C overlayer.…
Long-range pair potentials are presented for the fcc metals Ni, Au, Ag, Pt, Pd, Cu, and Al. Experimental data considered in deriving the potentials include the sublimination energies and stacking-fault energies as well as the lattice parameters, elastic constants, and vacancy-formation and -migration energies. A volum…
EXAFS has been measured at the Nb K-edge in the layered compounds NbSe 2 and at the Nb and Rb K-edges in the same crystal after intercalation with the alkali metal. Changes in bond length were measured to an accuracy of 0.004 AA. These changes were compared with changes in lattice parameters observed by X-ray diffract…
Arsenic selenide-telluride glasses have been investigated by X-ray absorption and photoelectron spectroscopy. The core electron energy shifts and chemical shifts in K-absorption edge measurements associated with the glass-crystal transitions of pure As 2 Se 3 and As 2 Te 3 have been studied. The effect of composition…
Synchrotron radiation sources, providing intense, tunable, polarized, and stable beams of ultraviolet and x-ray photons, are having a great impact on biology, physics, chemistry, materials science, and other areas of research. Synchrotron radiation has revolutionized solid-state photoelectron spectroscopy by enhancing…
In this paper we examine the mechanical and thermodynamic criteria which are necessary for equilibrium to exist in partial melts that are subject to hydrostatic stress. Existing theory satisfactorily demonstrates (1) that crystal‐liquid interfaces will have no sharp edges and will approach constant curvature and (2) t…
Degraded insulators of electronic components tend to ignite even when electrical energy supplied to them is less than 50 watts. This is also the case when the insulators are made of self extingushing polymeric materials. To evaluate the degradation of insulators, causes for the variation of data are investigated prima…
Synthetic crystals of tachyhydrite are trigonal, diffraction aspect R**, with hexagonal parameters a = 10.136 (1), c = 17.318 (2) Å, U = 1540.9 (3) Å3, Z = 3, Dc = 1.673 Mg m−3. Indexed powder data are given.
Abstract From the results of a structural analysis of cellulose crosslinked by a bifunctional reagent conclusions can be drawn merely on the distribution of crosslinks among individual hydroxyl groups. No information is available to what extent this distribution is caused either by different relative reactivities of t…
Temperature distribution on the surface of an energized polluted insulator has been measured using infra-red hermo thermovision techniques. Temporal variation of temperature has also been determined. Tests were carried out on a conventional ional cap and pin insulator unit. Results show that the maximum temperature of…