Materials Literature
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Chalcogenide bulk glasses exhibiting n-type conduction were first prepared by quenching the melts of mixtures of Ge, Se, and Bi2Se3 or Bi. The conditions for obtaining homogeneous glasses were examined, and measurements of resistivity and thermoelectric power were carried out on Ge20Bi10Se70 glass, one of the typical…
The influence of a rigid substrate on the static strain of an adsorbed incommensurate monolayer is discussed. It is shown that the strain energy is independent of relative translation of the two lattices but does depend on their relative orientation. A simple analytic form is given for the minimum energy orientation a…
Energy-band dispersions and electron lifetimes have been determined for both valence and conduction-band states of copper using angle-resolved photoemission with polarized synchrotron radiation in the $5\ensuremath{\le}h\ensuremath{\nu}\ensuremath{\le}35$ eV photon energy range. Dispersion relations for the occupied $…
The thermoelectric power of n-GaAs has been computed at different lattice temperatures and electron concentrations incorporating the band non-parabolicity, the p-function admixture and the effects of electron screening and degeneracy on scattering probabilities. All the relevant scattering mechanisms have been conside…
Time lags to breakdown in n-hexane have been measured in high over-voltages, using approximately 100 ns width rectangular pulses. At a constant field, the time lags are divided into two types, N and B, at a 'critical distance' d. Above d c , Laue plots have almost similar kinked-line characteristics; below d c , a str…
We have investigated the orientation dependence of the structure near the boron $K$ edge in electron-energy-loss spectra from hexagonal boron nitride. Angular distributions of spectra recorded from crystals with $c$ axis tilted at 45\ifmmode^\circ\else\textdegree\fi{} to the beam allow us to determine unambiguously th…
The electronic band structures of the beta , epsilon and gamma polytypes of GaSe are studied by the tight-binding method. The calculation takes into account interlayer interactions and the generally neglected lowest excited atomic states. The energy levels of the three polytypes differ from each other by 0.3 eV at mos…
Generalisations of the two apparently rational eigenvalues found by Thorson and Moffitt for the Jahn-Teller system Gamma 8 (X) tau 2 are studied. Equations of finite order are established for determining the strength D of the Jahn-Teller interaction of which an eigenvalue lies on a baseline. (A baseline is the line th…
A new fundamental radiation-induced defect in high-purity synthetic silica has been identified by electron-spin-resonance studies of $^{17}\mathrm{O}$-enriched Si${\mathrm{O}}_{2}$ as a peroxy radical ${\mathrm{O}}_{2}^{\ensuremath{-}}$ bonded to one Si in the glass matrix. The precursors of these defects are envision…
Abstract. — With Mossbauer effect and X-ray diffraction on magnetically aligned ErFe3 it has been shown that the easy axis of magnetization turns from the crystallographic c-axis to the 6-axis at 50 K with increasing tempe-rature. In the Er(Fei_:sCox)3 series from x = 0 up till x = 0.4 almost the same spin reorientati…
Abstract In a preceding paper the diffraction theory on this subject has been worked out by using far less approximations than those which had been involved in earlier tratments, arriving at more general and exact results. The approach used to obtain the expressions for the variance and integral breadth of reflections…
The depolarized light scattering from a phase-separated borosilicate glass was experimentally measured. The theory predicts that the internal stress field around the second-phase particles gives rise to a depolarized four-leaf-clover scattered-intensity pattern. The phase-separated and annealed specimen showed practic…
The permanent magnets which can be manufactured from rare earth base alloys have magnetic properties which substantially exceed the values obtained before with the Alnico and Ferrite magnets where the specific energy (from 3 to 6 times) and the resistance to de-magnetization (from 30 to 4 times) are concerned, but at…
Abstract The strain‐induced crystallization phenomenon of a crosslinked polymer network was studied using statistical, thermodynamics. The basic approach was essentially that used by Flory (1), but in this work Flory's assumption of only a single crystalline phase (the extended‐chain crystalline structure with chain p…
The ternary system Y6(Fe1-xMnx)23 exhibits unusual magnetic behavior. Although both Y6Mn23 and Y6Fe23 are magnetically ordered, these ternaries show a striking reduction in both Curie temperature and magnetization. In the compositional range of x = 0.5 to 0.75, there exists no magnetic ordering at liquid helium temper…
A simple mathematical model that includes (a) uniform liquor flow through a package and (b) Fickian diffusion of a dye within the fibres is described. The distribution of a dye within the package and the degree of levelness are calculated for constant dyeing conditions (e. g., constant temperature) and a dye with a li…
Abstract Wholly aromatic polysulfonamides of high molecular weight were prepared by the solution poly‐condensation of aromatic disulfonyl chlorides with aromatic diamines in tetramethylene sulfone and substituted pyridines as the acid acceptor. Polysulfonamides with inherent viscosities as high as 1.2 were readily obt…
Abstract Factors affecting the formation of hard elastic polypropylene and nylon 6,6 are described. In the case of polypropylene, it is shown that the morphology of the stress spin‐oriented fibers depends on the molecular weight, the molecular weight distribution, and the cooling rate. Narrow molecular weight distribu…
The authors' previous work on the fractography of cotton has been extended to include a comparison of cotton varieties, differences between individual fibers of different strength, fracture of mercerized cotton in water, fracture of crosslinked cotton (including tests in water, and at and between reversals), fractures…
Abstract The objective of this study was to develop a test which can accurately predict the contribution of coating characteristics to the control of rates of release of urea from SCU granules. It was assumed that product quality is a function of average coating thickness and uniformity of coating thickness. To achiev…