Materials Literature
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The creation probability of soliton-antisoliton pairs due to quantum-mechanical tunneling in the presence of an electric field in charge-density---wave condensates is calculated. This process gives rise to an additional electric conductivity strongly nonlinear in the electric field, which may account in part for the a…
Polyurethane rigid foam is widely used as a thermal insula tion material in low temperature service because of its low thermal conduc tivity. This paper describes the results of laboratory studies on various aspects of this application such as maintenance of insulation efficiency, corrosion protection, and friability.…
The electroreduction of thallium (I) on a mercury electrode from its solutions in molten calcium nitrate tetrahydrate has been studied using chronoamperometry, chronopotentiometry, and cyclic voltammetry. The early stages of metal deposition are controlled by a nucleation step as indicated by the maxima in current‐tim…
Progress of Theoretical Physics Vol. 59 No. 6 (1978) pp. 2151-2153 Effects of a Tensor Force on ψ Family in the Charmonium Model. II Hiroaki Yamamoto and Akitoshi Nishimura Progress of Theoretical Physics Vol. 60 No. 2 (1978) pp. 639-640 Decays of 3D1-Charmonium into ee and Relativistic Effects of Constituent Quarks Y…
The thermal parameters of Zn have been refined by the use of Bragg reflexions measured with Mo Kα and Cu Kα radiation for one temperature only. Several models of the anisotropic extinction correction have been examined. It is shown that the use of the extinction correction strongly influences the values of the thermal…
Abstract The specific heat of a AgNa(NO 2 ) 2 single crystal was measured between -90 and +55 °C. The entropy of the ferroelectric transition was found to be 9.9 J/mol·K and the critical exponent of the specific heat in the ferroelectric region is α'= 0.50 ±0.02.
The crystal structure of sodium sulfanilate dihydrate has been redetermined from single-crystal X-ray data collected at 78 K. Separate least-squares refinements were performed on the low-order data, the high-order data and the entire data set. The nonplanarity of the amino group has been reconfirmed. Difference densit…
Using nonrelativistic Hartree-Fock-Slater wave functions and Sternheimer's uncoupled perturbation-numerical method the valence shielding-antishielding factor $R$ including exchange has been calculated for Cr, ${\mathrm{Mn}}^{+}$, ${\mathrm{Fe}}^{2+}$, ${\mathrm{Co}}^{3+}$, ${\mathrm{Ni}}^{4+}$ (all in $3{d}^{6}$ isoel…
A method is described for estimating the phases of high resolution single-crystal diffraction data from proteins, by using as a starting point a set of low resolution phases (about 3 A) derived by multiple isomorphous replacement (or other) methods. The method consists in refining by least-squares the positions and th…
The structure of the compound Fe2WO6 is of the tri-α-PbO2 type, and it belongs to the crystallographic space group Pbcn (D142h). The lattice constants are a = 4.576, b = 16.766 and c = 4.967 Å, with four formula units per lattice point. Neutron (λ ~ 2.4 Å) diffraction patterns were taken at 300, 170, 77 and 4.2 K. Som…
Polarized-neutron diffuse-scattering methods were used to determine the spatial distribution of the magnetic moments in $\mathrm{Pd}\mathrm{Mn}$ alloys containing 0.23-, 0.46-, 0.99-, and 1.91-at.% Mn. The measurements, made on polycrystalline samples at 4.2 K in an applied field of 45 kOe, show a moment of about $4{\…
The free energy (Gibbs) of formation of Li 2 C 2 , CaC 2 , and Li 3 N and their activities in molten salt solutions at temperatures between 823° and 973°K have been determined by using the following galvanic cells Fe , Li ‐ Ca alloy | LiCl ‐ CaCl 2 eut . CaC 2 | C s , Fe I and Fe , Li c | LiCl ‐ LiF eut . Li 3 N | N 2…
The system B 2 O 3 ‐NaF‐NaBF, has been studied by subjecting selected compositions to thermal treatment in the range 400° to 600°C. Weight losses, chemical analyses, ir, Raman, and X‐ray diffraction techniques were used to define the composition of the crystalline phases and the structural units being formed in the sy…
A mechanism for producing open-end-spun core-spun yarns is described, and the method of operation is explained. Examples of open-end-spun core-spun yarns are given. Yarn properties are discussed, attention being drawn to the different functions performed by the core and the sheath.
Crystal Data Space-Group Tables lists over 17,000 materials whose space groups and symmetry have been determined mainly by x-ray diffraction. These tables comprise a companion publication to Crystal Data Determinative Tables. The space groups are listed in the same order and orientation as in International Tables for…
Abstract Communications are brief preliminary reports of research work in all areas of chemistry which, on account of its fundamental significance, novelty, or general applicability, should be of interest to a broad spectrum of chemists. Authors of communications are requested to state reasons of this kind justifying…
The use of platinum group metal catalysts supported on ceramic monoliths for control of gaseous emissions from automobiles and chemical plant is now well established. Research in the Johnson Matthey Laboratories and at AERE Harwell, aimed at meeting the demand for more effective catalysts, has resulted in a new genera…
for powdery or relaxed samples occurs around 352 to 356 K for the suspension-polymerized PVC sample and 348 to 351 K for bulk-polymerized sample.
Extensive fuel performance data obtained from Canadian Deuterium Uranium (CANDU) power reactors and experimental reactors are analyzed. Various modes of power ramping that cause fuel defects are identified, and fuel defect criteria are derived. The probability of a defect occurring in a power ramp is found to depend o…
Abstract The, nature of polymer surfaces has received increasing attention as the use of these materials, in a variety of forms, increases yearly. Modifications of polymer surfaces for adhesion, friction, and diffusion oriented appiications have necessitated a careful analysis of the surfade region morphology (surface…