Materials Literature
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A method of estimating diatom concentrations in sediment samples by the addition of known quantities of microspheres is described. Polystyrene or glass microspheres can be used and their concentration in suspensions can be rapidly calculated with an electronic particle counter. Test results are compared with results f…
The success or otherwise of catalyst preparation or modification depends on the availability of suitable characterization techniques to determine the condition of the catalyst. There are many techniques available for this purpose including x-ray powder diffraction, electron microscopy, photoelectron spectroscopy, and…
Approximate constitutive equations are proposed for use in the analysis of the rate-dependent deformation of metals at temperatures in excess of a homologous temperature of 0.5. The constitutive equations are formulated within the scope of some recent theories of elastoviscoplasticity with internal variables, but empl…
L'analyse des calibrations existantes pour différentes substances montre que l'intensité de l'absorption des I.R. de 3 µm par les hydroxyles dépend de la fréquence. Quand on prend en compte le facteur d'anisotropie γ, une raie unique de calibration pour le coefficient d'absorption molaire intégral I peut, en première…
Most of Volume 9A of Reviews in Mineralogy treats amphiboles and other hydrous pyriboles as isolated systems. It reviews the structural complexity and resulting chemical variability and diversity of petrologic behavior of amphiboles, whereby Volume 9A contains a hefty dose of petrology and in contrast, Volume 9B is de…
The temperature dependence of the structure factor of glassy ${\mathrm{As}}_{2}$${\mathrm{Se}}_{3}$ has been measured. Surprising results were found for the first peak, which shows a large increase in intensity from 40 K to the glass transition temperature, ${T}_{g}$; in contrast the second peak decreases in this rang…
The authors study a two-parameter one-dimensional lattice model embedded in three-dimensional space at T=0, that has indirect oscillatory interactions between neighbours. It can describe succession of modulated structures separated by first-order phase transitions. Qualitative agreement with experimental data obtained…
The molecular ordering in the nematic and smectic-C phases of the liquid crystal p-n-nonyloxy benzoic acid (NOBA) is investigated. The phase transition from isotropic to nematic phase is of first order. In the nematic phase over a wide range of temperatures the order parameter remained constant. In the low temperature…
Photo-stimulated luminescence provides a method of radiation dosimetry in which repeated readouts from an irradiated sample are possible without erasing the initial dose information. It is found that in CaSO4:Dy, photo-stimulated luminescence as well as thermoluminescence processes are both originating from the same t…
The stability of planar faults on possible slip planes in the DO19 structure is investigated using crystal symmetry considerations and the restoring force calculated for these faults. It is found that the superlattice intrinsic stacking fault on the basal plane and the antiphase boundaries on prismatic {1010} and {112…
The complex piezoelectric constants, d 21 , d 22 and d 23 , of ferroelectric AgNa(NO 2 ) 2 have been measured by two quasi-static methods; one is the optical interferometric method and the other is based on a comparison with the piezo-electric constant of quartz. The measurement covered the temperature range from 40°C…
Band structure calculations based on the extended Hückel method order energetically the 36 arsenic-like structures having the NaCl size unit cell in a way which is compatible with the observed crystal structures. Black phosphorus is the most stable of the 36, and the arsenic layer type is number seven. Energy differen…
We present an evaluation of the electron-phonon coupling parameter $\ensuremath{\lambda}$, using the McMillan formalism, for several classes of stoichiometric mono- and dihydrides with a metallic underlying fcc structure. We calculate the electronic term $\ensuremath{\eta}$ and use experimental estimates for the phono…
The Ag-deposited Se80Ge20 (at. %) amorphous films are found to show a large chemical shift (∼1.2 eV) in the Se 3d level toward lower binding energies and to form a Ag2Se phase on the surface region. The chemical shift of the Se 3d level by Ag photodoping becomes large with increasing UV exposure (15 mW/cm2) and is sat…
For the first time, infrared integrated absorption intensities and extinction coefficients have been determined for both the linearly adsorbed (high frequency-HF) and the bridged-bonded (low frequency-LF) forms of CO on Pt. Platinum dispersed on η-Al2O3, SiO2, SiO2–Al2O3, and TiO2 was characterized by both hydrogen an…
Susceptibilities of single crystals of CsCuCl 3 are measured in 4.2 K< T <500 K for H ⊥ c and H // c . Behaviors characteristic to a one-dimensional Heisenberg ferromagnet with weak interchain interactions are observed. The behaviors are analyzed by the high temperature expansion approximation, and intrachain and inte…
The structures of arsenic and black phosphorus can be regarded as distortions of the simple cubic or NaCl structure. The presence of more than four electrons per site results in the breaking of three of the six linkages around each atom in the NaCl structure. A generalization of Pólya’s enumeration theorem is proven w…
A new class of organic quinoid systems possessing intrinsically large, nonlinear second-order optical susceptibilities has been developed based on theoretical calculations and dc-induced second-harmonic generation measurements of the molecular second-order optical susceptibilities β. For one example, 2-(4-dicyanomethy…
A metal-to-insulator transition is observed using angle-resolved photoemission at the $1{T}_{2}\ensuremath{\rightarrow}1{T}_{3}$ phase transition of Ta${\mathrm{S}}_{2}$ at $T\ensuremath{\sim}200$ K: a 0.125-eV band gap, $d$ subbands, and Fermi-surface modifications occur. High-resolution (0.15-eV) Ta $4f$ core-level…
A silica supported Ni catalyst has been investigated by electron magnetic resonance between 293 and 4.2 K. A relatively narrow absorption signal with linewidth ΔHpp?400 Oe is observed at temperatures ?150 K as a result of motional averaging of the magnetocrystalline anistropy field Ha of the Ni particles resulting fro…