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 co-ordination geometry of the NiII complex with the new macrocyclic ligand L, which contains a side chain, is controlled by the pH of the solution, the square-planar yellow diamagnetic form and the octahedral blue paramagnetic one being stable below and above pH 6·3, respectively.
Nuclear fuels for the high‐temperature gas‐cooled reactor (HTGR) consist of spherical kernels of actinide compounds contained in gaslight pyrolytic carbon and SiC. The fuel kernels migrate up the temperature gradient and into the coating layers. A theoretical analysis of in‐reactor migration data indicates that a soli…
Abstract The solid, water‐insoluble sorbent called Super Slurper that swells in water is a base hydrolyzed starch‐polyacrylonitrile graft copolymer in which the nitrile functionality has been converted to a mixture of carboxamide and alkali metal carboxylate. A process for making the polymer in multipound quantities h…
Abstract Reactions of OH( v = 1) with HBr, O, and CO have been studied at 295°K using a fast discharge flow apparatus: equation image The reaction O + HBr → OH( v = 1) + Br was used as a source of OH( v = 1), and subsequent chemical reactions of the excited radical were followed using EPR spectroscopy. Rate constants…
Mössbauer data for a large number of gold(I) complexes are presented. From these data and previously published work it is concluded that: (i) the bonding involves only 6S and 6p orbitals; (ii)π acceptance by ligands from gold is negligible; (iii) the gold atom tends to concentrate S character in bonds to such ligands…
Data on irradiation growth of Zircaloy is presented. Irradiation growth is defined as irradiation-induced changes in dimensions in the absence of an applied stress. It is shown that the primary variables are fluence, irradiation temperature, amount of prior cold work, heat treatment, and texture. For recrystallized Zi…
The Alexander-Kaplan method is applied to analyse the E.S.R. spectra of symmetrical three-spin systems, undergoing fast, intermediate and slow rotational diffusion in nematic liquid crystals. Particular emphasis is given to the slow-motional region. The line shapes are calculated from a spin hamiltonian, which conside…
The Avcothane 51 elastomer, a member of a series of proprietary materials best characterized as polyurethane/poly(dialkylsiloxane) block copolymers, displays considerable hemocompatibility without any incorporated anticoagulants. In the form of intra-aortic balloons, the elastomer was implanted in several thousands of…
The rates of oxidative addition of methyl iodide to the comolexes [PtR2(bipy)][bipy = 2,2′-bipyridyl; R = Me, Ph, 4-XC6H4(X = F, Cl, Me, or OMe), and 3-XC6H4(X = F or OMe) have been studied.The second-order rate constants follow the series R = Me > 4-MeOC6H4 > 4-MeC6H4 > 3-MeOC6H4 > Ph > 4-FC6H4 > 4-ClC6H4 > 3-FC6H4,…
Neutron diffraction study was carried out on single crystals of the perovskite oxide SrFeO 3- x ( x =0.1). SrFeO 3- x ( x =0.1) has a proper screw spin structure with the propagation vector parallel to [111] direction and its Néel temperature is 118 K. The electron configuration of Fe 4+ (3 d 4 ) ion is close to the l…
Views Icon Views Article contents Figures & tables Video Audio Supplementary Data Peer Review Share Icon Share Twitter Facebook Reddit LinkedIn Tools Icon Tools Reprints and Permissions Cite Icon Cite Search Site Citation Russell J. Boyd; Electron density partitioning in atoms. J. Chem. Phys. 1 January 1977; 66 (1): 3…
A free-ion-model crystal-field calculation has been performed for YAl${\mathrm{O}}_{3}$:${\mathrm{Er}}^{3+}$. A free-ion calculation was done by fitting a free-ion Hamiltonian, which included Coulomb, spin-orbit, configuration, spin-spin, and spin-other-orbit interactions. The coefficients which gave the best least-sq…
Possible losses of trace elements during dehydration of marine zoological material with a high water content were studied by means of radioactive tracers, using the oyster Crassostrea gigas as an example. It is probable that no losses occurred with chromium, iron, manganese, cobalt and zinc, but serious losses of sele…
Analytical methods are given which enable one to describe geometrically layers of large curvature in a smectic phase. Dupin cyclides in focal domains are taken as examples. The curvature energy of focal domains is calculated. The difference between normal focal domains (built on an ellipse and an hyperbola), and parab…
The possibility of the smectic A to C phase transition is discussed, using a model based on the dipole-dipole interaction of the polar bonds of the molecules, which are supposed to rotate randomly around their long axis in both the A and C phases. Two different choices of the two-particle distribution function are use…
Thin gold films were vapor deposited onto KCl single crystals under a variety of substrate temperatures, residual gas pressures, and deposition rates. The films were subsequently examined by high‐resolution transmission‐electron microscopy. The use of the defocus contrast technique revealed a large number of small (10…
Abstract Significance of symmetry in representing real‐ and reciprocal‐space properties of a crystal and of its constituents is discussed in terms of symmetry eigenfunctions. The formation of the site‐symmetrized multipole expansion for the 32 crystal point symmetries is shown, and the mutual relations between the rea…
Abstract A computer program is described that permits the refinement of the static charge deformation in a flexible atom‐centered multipole expansion, together with positional and vibrational parameters, against X‐ray and neutron data. Other options allow for rigid‐body constraints on some or all of the atomic vibrati…
Abstract Shake‐up phenomena in a series of para ‐substituted polystyrenes have been studied by ESCA. Comparison with other spectroscopic data and with theoretical calculations within the sudden approximation, equivalent cores model, and CNDO SCF MO formalism identifies the shake‐up structures as arising predominantly…
Evidence is provided that silver zeolites can be used for the decomposition of water into hydrogen and oxygen; the process consists of a photochemically induced reduction of the zeolite, followed by an oxidative thermal desorption of hydrogen.