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Asymptotic Distributions for the Failure of Fibrous Materials Under Series-Parallel Structure and Equal Load-Sharing
Asymptotic distributions are obtained for both the strength and the time to failure of a fibrous material for which mild bonding or friction exists between fibers. The analysis is based on the chain-of-bundles probability model, and equal load sharing is assumed for the nonfailed fiber elements in each bundle. Asympto…
Gas-phase oxidation catalysis by transition-metal cations
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTGas-phase oxidation catalysis by transition-metal cationsManfred M. Kappes and Ralph H. StaleyCite this: J. Am. Chem. Soc. 1981, 103, 5, 1286–1287Publication Date (Print):March 1, 1981Publication History Published online1 May 2002Published inissue 1 March 1981https://pubs.ac…
Magnetic structure of small NiFe2O4 particles
The magnetic structure of small NiFe2O4 particles has been investigated. Samples (in the few hundred angstrom size range and up) were prepared by chemical precipitation followed by a heat treatment at relatively low temperatures. Mössbauer spectra of the 57Fe nuclei, obtained with a longitudinal magnetic field applied…
THE ADSORPTION AND PRECIPITATION OF PHOSPHATE ONTO CALCITE
Summary Scanning electron micrographs show that the reaction products of solution phosphate and calcite are hemispherical, coral‐like growths on calcite surfaces. Electron probe micro‐analysis indicates that these are a calcium phosphate, and solution data plotted against solubility isotherms suggest that dicalcium ph…
Characterization of clays by organic compounds
Abstract Many problems—from soil research to ceramics—require a reliable characterization of the clay minerals involved. This can be done using four clay-organic reactions: (i) staining tests and dye adsorption; (ii) glycerol and glycol adsorption; (iii) intercalation; (iv) alkylammonium ion exchange. Dye adsorption (…
A Dislocation Model for Fatigue Crack Initiation
The slip band formed in a grain on the material surface is a preferential site for crack initiation during low strain fatigue of polycrystalline metals. The forward and reverse plastic flow within the slip band is modeled in the present study by dislocations with different signs moving on two closely located layers, a…
Physical properties and phenomenological theory around the successive high-temperature phase transitions of (C2H5NH3)2CuCl4
Calorimetric, thermal expansion and optical measurements as well as optical observations confirm the sequence of structural phase transitions D 4h 17 (I) to D 2h 18 (II) to D 2h 12 (III) in the perovskite layer compound (C 2 H 5 NH 3 ) 2 CuCl 4 . For the I to II change the results show second-order character together…
Beiträge zur Kenntnis des chromophoren Systems der Corrine, IX. Über eine neuartige Thermolyse‐Reaktion am Dicyano‐cobyrinsäure‐heptamethylester
Abstract Durch Erhitzen von Dicyano‐cobyrinsäure‐heptamethylester unter bestimmten Bedingungen wird zwischen den C‐Atomen 7 und 8 unter formaler Abspaltung von Essigsäure‐methylester eine neue Doppelbindung gebildet.
Linear Magnetoresistance Caused by Sample Thickness Variations
Experiments are presented which show that surface imperfections can give rise to a larger linear magnetoresistance than previously supposed; in fact, large enough to explain many hitherto-unexplained published results. A theoretical model, which takes into account both the finite width of the sample and the Hall field…
Dislocations and the Commensurate-Incommensurate Transition in Two Dimensions
The incommensurate adsorbed solid is found to become unstable to dislocations when the lattice period approaches that of a sufficiently low-order commensurate phase such as a 2\ifmmode\times\else\texttimes\fi{}1 rectangular overlayer or the $(\sqrt{3}\ifmmode\times\else\texttimes\fi{}\sqrt{3})R30\ifmmode^\circ\else\te…
Aggregation of nitrogen in diamond, including platelet formation
Abstract Nitrogen occurs in most natural diamonds in concentrations of up to 0.3 at. %. In about 0.1% of diamonds, the nitrogen occurs as single substitutional atoms but in most diamonds aggregates of two or more nitrogen atoms occur. The various types of aggregate have been identified by detailed study of optical abs…
Radiation grafting of poly(ethylene terephthalate) (PET) fibre, II. Hydrolysis of grafted poly(vinyl acetate) to poly(vinyl alcohol)
Abstract Poly(ethylene terephthalate) fibres grafted with poly(vinyl acetate) by γ‐radiation were hydrolysed under alkaline and acidic conditions in order to obtain poly(ethylene terephthalate)‐graft‐poly(vinyl alcohol) fibres. In alkaline media poly(ethylene terephthalate) degraded without appreciable conversion of a…
X-ray diffraction contrasts of section topographs by extended lattice deformations
The analogy between the ray-optical (Eikonal) theory of X-ray diffraction in distorted crystals and mechanics gives the possibility to explain qualitatively the contrast in section topographs of crystals containing one-directional varying lattice-plane distances. The formation of topographic contrasts is discussed for…
Measurements of angular distribution of the backscattered electrons in the energy range of 5 to 30 keV
Measurements of the directional coefficient of backscattered electrons are carried out in the incidence plane of the beam. Samples of C, Al, Cu, Ag, Au, and U are investigated with primary energies 5, 10, 20, and 30 keV for normal incidence and for the incidence angles 30°, 60°, and 80°. The analysis of the obtained r…
Induced phase transitions in ferroelectrics with diffuse phase transition
Dielectric, thermal, electrocaloric, elastic, optical, and electromechanical properties of three ferroelectrics with diffuse phase transition (PLZT 8/65/35 ceramics, lead magnesium niobate and strontium barium niobate single crystals) are investigated in dependence on temperature and electric field strength. It is sho…
Conduction-Band Surface Plasmons in the Electron-Energy-Loss Spectrum of GaAs(110)
Apart from Fuchs-Kliewer surface phonons, conduction-band surface plasmons and probably intraband single-particle scattering contribute to the electron-energy-loss spectra (primary energy \ensuremath{\sim}5 eV, resolution 10 meV) measured on clean, UHV-cleaved, $n$-type GaAs(110) surfaces. Coupling between surface pho…
The luminescence of cadmium tungstate (CdWO4)
The luminescence of pure single crystals of CdWO4 is reported. Two emission bands are observed. Their decay times are measured and discussed.
Nonlinear Conductivity and Noise due to Charge-Density-Wave Depinning in Nb Se 3
A simple model for the depinning and dynamics of a sliding charge-density wave is presented. The model consists of viscously damped motion in a periodic potential and accounts for the main features of the nonlinear conductivity, noise, and ac-dc coupling in the charge-density-wave state of Nb${\mathrm{Se}}_{3}$ at low…