Materials Literature
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Huge magnetically induced strains (\ensuremath{\sim}0.2%) were observed in cubic Tb${\mathrm{Fe}}_{2}$ at room temperature. An anomalous "positive" temperature dependence for the magnetostriction is found for Dy${\mathrm{Fe}}_{2}$, yielding a peak in the magnetostriction exceeding 600 \ifmmode\times\else\texttimes\fi{…
Abstract Tensile bars of an isotactic propylene homopolymer and an ethylene–propylene copolymer were prepared by injection molding under a variety of melt temperatures and injection pressures. The effects of these processing variables on morphology and crystalline orientation were studied using optical microscopy and…
The permittivity of single-crystal single-domain strontium titanate has been measured in detail in the [001], [011], and [111] directions, as a function of temperature (from 4.2 to 300 °K), electric field (from −23 000 to +23 000 V/cm, and frequency (from 1 kHz to 50 MHz). The free energy of the crystal is determined…
Abstract The changes in temperature and crystallinity of polymer during nonisothermal crystallization were theoretically analyzed assuming a cooling condition under which heat transfer occurs at a rate proportional to the difference in temperature between polymer and the environment. When a plateau appears in the temp…
Using electronegativity differences the interactions within the primitive cell of a typical substitutional alloy of two binary compounds are estimated. It is shown that the important interactions for energy gap bowing are those between intersubstitutional atoms. From this and a virtual crystal approach, trends in the…
The K-absorption discontinuity of arsenic has been studied in the pure element and in six compounds in which it is trivalent. It is observed that the discontinuity shifts towards the high energy side in certain compounds and towards the low energy side in some others. It has been shown that the positive or the negativ…
Optical reflection and transmission measurements have been made between 6 eV and 13 eV on specimens of natural muscovite, phlogopite, biotite and a synthetic fluorphlogopite. Reflectivity peaks are observed near 9.9 eV and 11.8 eV and are thought to be due to the silicate structure of mica. An absorption edge occurs n…
The polarized (${I}_{\ensuremath{\parallel}}$) and depolarized (${I}_{\ensuremath{\perp}}$) scattered light intensity by fluctuations of the order parameter $Q$ near the isotropic-nematic phase transition of para-methoxybenzylidene para-$n$-butylaniline has been measured as a function of the scattering angle over a ra…
The valence-band structures of MnO, CoO, NiO, ${\mathrm{Cu}}_{2}$O, CuO, and Re${\mathrm{O}}_{3}$ have been obtained by x-ray photoemission spectroscopy. It is found that in every case a narrow metal $d$ band lies above the center of the oxygen $2p$ valence band.
A conventional absolute method was used for the measurement of the thermal conductivity of pressed and sintered p-type Bi2Te3–Sb2Te3–Sb2Se3 alloys and n-type Bi2Te3–Bi2Se3 alloys in the temperature range of 300 to 600 K. The measurements were made in directions parallel and perpendicular to the pressing direction. Mea…
The theoretical distribution, with exact second moment, of the number of photoelectrons emitted by an extended photodetector illuminated with partially coherent light is first derived. Then the parameter N, the number of degrees of freedom, is obtained from the second moment of the distribution, for [Formula: see text…
An experimental study of the constitution of the As–Te glasses has been carried out, using glass-forming-ability measurements, high-angle diffraction, differential thermal analysis, and other thermodynamic determinations. Evidence is definitely given for a difference of valency between crystalline and glassy states. A…
After a brief review of the principal features associated with energy-band diagrams of ideal transition-metal monoxides having localized vs itinerant $d$ electrons, modification of these diagrams is discussed for real crystals in the systems $\mathrm{Ti}{\mathrm{O}}_{x}$ and $\mathrm{V}{\mathrm{O}}_{x}$, which have it…
The interaction between strain and order parameter at the structural transition in SrTi${\mathrm{O}}_{3}$ is investigated by ultrasonic measurements of attenuation, velocity shifts, and stress dependence of the transition temperature ${T}_{a}$. A method is described by which measurements of domain attenuation are used…
The rate of multiphonon relaxation of rare-earth ions in crystals has been calculated using the Kubo representation of the rate constant in terms of linear response time correlation functions. The nonadiabatic electron-phonon operator arising from the effect of the kinetic energy of the ions on the Born-Oppenheimer ba…
Magnetic susceptibility measurements have been made between 1.5 and 20°K on [(C2H5)4N]2CoCl4. The results show that the CoCl4 2− tetrahedra are oriented such that their unique axes lie in or near the (001) plane while maintaining the tetragonal symmetry exhibited by the crystal at room temperature. Values for the para…
The reflectivity of a thick sputtered film of V${\mathrm{O}}_{2}$ has been measured in the energy range 0.5-11.0 eV at room temperature. The complex dielectric constant (${\ensuremath{\epsilon}}_{1},{\ensuremath{\epsilon}}_{2}$) and the complex index of refraction ($n,k$) have been obtained from the reflectivity measu…
The local-empirical-pseudopotential method is used to calculate the electronic band structure of Sn${\mathrm{S}}_{2}$ and Sn${\mathrm{Se}}_{2}$. The pseudopotential form factors for the constituent elements Sn, S, and Se are determined from previous pseudopotential calculations for other crystals. Slight adjustments w…
The cubic compounds $\mathrm{Ti}{\mathrm{O}}_{x}$ and $\mathrm{V}{\mathrm{O}}_{x}$ have a broad homogeneity range with $x$ varying from about 0.75 to 1.30 and a total vacancy content varying between 11 and 20%. Golden $\mathrm{Ti}{\mathrm{O}}_{x}$ is a typical metal with a temperature- and composition-independent resi…
Optical absorption measurements near the absorption edge are presented for three bulk semiconductor glasses: ${\mathrm{As}}_{2}$${\mathrm{S}}_{3}$, ${\mathrm{Ge}}_{33}$${\mathrm{As}}_{12}$${\mathrm{Se}}_{55}$, and ${\mathrm{Ge}}_{28}$${\mathrm{Sb}}_{12}$${\mathrm{Se}}_{60}$. The weak absorption tails observed below th…