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。
The theory for the spin Hamiltonian parameters of low spin cobalt(II), d 7 , complexes has been developed to third order in perturbation theory for all reasonable ground states. Two extensions beyond previous treatments have been made: (1) the spin–orbit mixing of excited quartet states into the doublet ground state h…
Resonant Raman scattering in ${\mathrm{Cu}}_{2}$O has been studied at low temperature in the vicinity of its phonon-assisted $1s$ yellow excitonic absorption edges using a cw continuously tunable dye laser. The multiphonon Raman modes which show resonance enhancement in this region are the following: ${\ensuremath{\Ga…
A Landau theory is proposed for charge-density waves (CDW) in transition-metal dichalcogenides with the charge density as an order parameter. The theory predicts the sequence of phases, normal-state---incommensurate-CDW---commensurate-CDW with decreasing temperature, separated by first-order phase transitions. The pea…
High-angular-resolution (\ensuremath{\sim}8\ifmmode\times\else\texttimes\fi{}${10}^{\ensuremath{-}6}$ rad), high-energy (75 keV), electron scattering from graphite thin films demonstrates energy losses due to the excitation of optical surface guided modes. Measurements of the dispersion offer considerable support for…
A shallow earthquake focus mechanism is modeled by a plane strain shear crack extending at a nonuniform rate under the action of general loading. An equation of motion of the crack tip is determined in terms of a specific fracture energy, i.e., a surface energy, by applying an overall energy balance fracture criterion…
A new type of beam deflector is described which involves an electrically induced variation of the optic axis across a liquid-crystal cell. Light polarised in the plane of the optic axis can be deflected through a half-angle of 20°, with slew rates in excess of 200°/s.
A new process for preparing uranium and plutonium metals has been developed. The process is based on the high extractability of the elements with sodium amalgam from aqueous solutions. After extracting the uranium or plutonium with sodium amalgam, the resulting amalgam was heated in vacuum so that mercury and sodium w…
Two patients in whom corrosion failure of stainless steel implants occurred had the surgically removed implants subjected to metallurgic analysis. Both implants showed marked pitting corrosion and required removal due to adverse tissue reaction. Analysis of the failed implants showed them to be fabricated of alloys wi…
The copper(II) methanesulphonate tetrahydrate and zinc(II) methanesulphonate tetrahydrate are both new compounds which crystallize in monoclinic space group P21/c. Their unit-cell parameters and indexed powder patterns are given.
Views Icon Views Article contents Figures & tables Video Audio Supplementary Data Peer Review Share Icon Share Facebook Twitter LinkedIn Email Tools Icon Tools Get Permissions Cite Icon Cite Search Site Citation R. NATARAJAN, P.C. ANGELO, N. T. GEORGE, R. V. TAMHANKAR; Dezincification of Cartridge Brass. CORROSION 1 A…
Abstract The thermal decomposition of nickel hydroxides prepared from aqueous nickel chloride solution on addition of alkali under various conditions has been examined by thermogravimetry, differential thermal analysis, X‐ray diffraction study, visible and infrared spectrophotometry, magnetic susceptibility measuremen…
An airlock door modification for the JEM 100B electron microscope is described. This modification permits prefrozen specimens to be introduced into the microscope without frost forming on the specimen or the specimen warming excessively. The imaging of hydrated biological material using frozen specimens is demonstrate…
High resolution absorption and magnetic circular dichroism (M.C.D.) spectra are reported for Ru4+ (4d4) in the cubic hosts Cs2ZrCl6 and Cs2SnBr6. The spectra were recorded at liquid helium temperature over the ranges 16 000–26 000 cm-1 and 11 000–22 000 cm-1 respectively. All of the major features can be interpreted i…
A large number of products was synthesized and the flame-retardant properties on polyester/cotton blends determined. Phosphonium salt oligomers were more efficient on blends than the conventional phosphonate used on cellulosics. Among the reasons given to substantiate this conclusion is the observation that the oligom…
Abstract The temperature variations of the spontaneous magnetization and spin paramagnetic susceptibility are calculated numerically, using molecular field theory, for the combined model of localized spins and itinerant electrons proposed by Edwards for some 3d transition metals. A simple parabolic band is assumed for…
The magnetic moment and heat capacity of a 1.170 cm diam spherical single crystal of electrically polarized β-Tb2(MoO4)3 have been measured at stabilized fields of 500, 1000, 1500, 2500, 5000, 10 000, 15 000, 25 000, 40 000, 65 000, and 90 000 G, along the c crystal axis, and over the range 0.4–4.2 °K. The heat capaci…
Friction and wear-caused mechanical failures and maintenance normally have their roots in phenomena based on tribology, the science and technology of interacting surfaces in relative motion. Developments in tribology since the publication of the Jost Report have utilized existing and new knowledge from physics, chemis…
A large variety of graphitic materials have been tested in an arc heated air stream at a surface pressure of 4.3 atm and a nominal surface temperature of 3925 K. Included were commercial and developmental grades of artificial graphites, both two and three dimensional carbon-carbon composites, composites seeded with re…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTPhotochromism of quinolylhydrazones. III. Mechanism of isomerization of the photocolored .alpha.-quinolylimino-(Z)-hydrazone to the .alpha.-quinolylamino-(E)-hydrazoneJohn L. Wong and Mona F. ZadyCite this: J. Org. Chem. 1975, 40, 17, 2512–2516Publication Date (Print):August…
Abstract The tetraphosphorus tetraselenide P 4 Se 4 is prepared and described for the first time. It is synthetised easily by heating between 250°C and 300°C a mixture of selenide P 4 Se 3 and selenium. It exists under two allotropie forms, α P 4 Se 4 transforming in β P 4 Se 4 at 300°C. α P 4 Se 4 cristallises in the…