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。
With high-resolution electron microscopy new crystal structures were found in the binary system of Nb 2 O 5 WO 3 oxides. The compounds are proposed to have the mole ratios 4Nb 2 O 5 . 22WO 3 and 4Nb 2 O 5 . 50WO 3 . The crystal structures are ascribed to intimate intergrowths of two known structures, the ReO 3 type an…
Suitable weighting schemes for use in tangent-formula phase development and refinement are discussed, and a statistically based weighting scheme, which can easily be incorporated in existing computer programs, is proposed. Examples of the use of this method in structure solution and completion are presented for a prev…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTX-ray photoelectron spectroscopy of a copper(III) macrocyclic complexWilliam E. Keyes, William E. Swartz, Jr., and Thomas M. LoehrCite this: Inorg. Chem. 1978, 17, 11, 3316Publication Date (Print):November 1, 1978Publication History Published online1 May 2002Published inissu…
Form factors calculated from several theoretical models show that the Xα method is accurate to about 1%. With the latter scheme and the Watson-sphere model the atomic form factors for O 2- and N 3- are computed for varying sphere radii. To a first approximation this radial variation accounts for the different environm…
In model experiments under controlled conditions of pH, particle size and amount of glucose, changes in the free Fe oxides (Fe d ) and acid oxalate soluble Fe (Fe o ) of six soils were studied after inoculation with iron-reducing, nitrogen-fixing Clostridia. In all soils, the total amount of Fe d as well as crystallin…
Abstract Dans la série des composés de formule globale MSbS 2 NaSbs 2 Présente deux Variétés allotropiques, NaSbS 2 α obtenu par refroidissement lent jusqu' à la température ambiante est monoclinique, groupe d'espace C2/c, a = 8,232(1) Å, b = 8,52(2) Å, c = 6,836(1) Å, β, = 124. 28° (1), Z = 4. NaSbS 2 β obtenu par tr…
Two types of copper/water heat pipes have been developed for cooling of both the rotor and the stator of an asynchronous electric motor which shall be used as a high-performance locomotive drive. For the stator axial groove heat pipes are used with a slight liquid overfill. The rotor heat pipes have cirumferential gro…
Binder phase (primarily chloride or nitrate) formation was examined in YX 3 ‐NaOH‐H 2 O, Y 2 O 3 ‐acid‐H 2 O, and Y 2 O 3 ‐salt‐H 2 ‐O systems. The cementitious phase consisted mostly of plate‐ (or needle‐) shaped hydroxy salts of the general formula Y 2 (OH) 6‐m X m n H 2 O, where m and n normally equal one. These bi…
Elasticity, internal friction, and thermal expansion were measured at temperatures up to 1500°C to characterize the micro‐cracking behavior of HfO 2 . Crack‐free HfO 2 showed consistent, typical changes in these properties with temperature. Micro‐cracked HfO 2 showed hysteresis in the elastic moduli and thermal expans…
Hypertension, diabetes mellitus, hypercholesterolemia, and smoking are known coronary risk factors. It has been our impression that premature graying of the hair also predisposes individuals to myocardial infarctions. To test this hypothesis, we evaluated all of the patients under the age of 50 who were admitted to th…
The Lorentz force on an electron is utilised to separate out the electron component from the open beam of a Clinac-18, operating in the X-ray mode. The experimental arrangement is such that the mixed beam (comprising the primary photons, the scattered photons and the contamination electrons) enters an external magneti…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTRefinement of the crystal structure of orthorhombic zinc chlorideH. L. Yakel and J. BrynestadCite this: Inorg. Chem. 1978, 17, 11, 3294–3296Publication Date (Print):November 1, 1978Publication History Published online1 May 2002Published inissue 1 November 1978https://pubs.ac…
The oxidation of the active, high energy density materials, titanium and titanium hydride, has been studied by electrochemical and electron spectroscopic techniques. The apparent thickness of the oxide was controlled by the magnitude of the applied potential across thin (200–6000Å) films of these materials. Our electr…
The structural phase transition in the ferroelectric semiconductor alloy series ${\mathrm{Sn}}_{x}{\mathrm{Ge}}_{1\ensuremath{-}x}\mathrm{Te}$ has been investigated using high-precision x-ray techniques. The spontaneous strain occurring at the cubicrhombohedral transition has been measured as a function of temperature…
Abstract The dark brown anti-ferromagnetic modification of (C 5 H 5 ) 2 Mn crystallizes ortho-rhombic, space group Pna2 1 (or Pnam) with a= 1402.7(2), 6 = 582.9(1), c = 996.5(1) pm and Z = 4. It forms polymer chains with a zigzag arrangement of C 5 H 5 Mn units and additional bridging C 5 H 5 -rings between adjacent i…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTThe dioxygen adducts of several manganese(II) porphyrins. Electron paramagnetic resonance studiesBrian M. Hoffman, Thomas Szymanski, Theodore G. Brown, and Fred BasoloCite this: J. Am. Chem. Soc. 1978, 100, 23, 7253–7259Publication Date (Print):November 1, 1978Publication Hi…
The mechanisms by which chlorides are removed from marine iron artifacts during washing processes were investigated. By comparing the decomposition rates of FeOCl and the chloride extraction rates it was shown that, under most conditions, the chloride removal process is diffusion controlled. The implications of this w…
The thermal radiation from metals is calculated by including the Holstein processes of phonon-assisted and surface-assisted scattering in the free-electron model. This approach provides a fairly accurate description of the experimentally measured total emissivity of good conductors in terms of the dc resistivity and t…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTRate of electron exchange between iron, ruthenium, and osmium complexes containing 1,10-phenanthroline, 2,2'-bipyridyl, or their derivatives from nuclear magnetic resonance studiesMan-Sheung Chan and Arthur C. WahlCite this: J. Phys. Chem. 1978, 82, 24, 2542–2549Publication…
Abstract Dynamic mechanical properties of polystyrene (PS) and polymethylmethacrylate (PMMA) filled with glass beads and mica flakes have been investigated. The α‐dispersion temperature ( T α ) increases with filler content in each system. The increase in T α is larger for PMMA than for PS in the case of the same fill…