Materials Literature
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Volume 15 of Reviews in Mineralogy is written with two goals in mind. The first is to derive the 32 crystallographic point groups, the 14 Bravais lattice types and the 230 crystallographic space group types. The second is to develop the mathematical tools necessary for these derivations in such a manner as to lay the…
Volume 22 of Reviews in Mineralogy is a book exclusively devoted to three minerals: the Al2SiO5 polymorphs - andalusite, sillimanite, and kyanite. It covers a wide variety of topics that must be considered in the analysis of metamorphic systems and illustrates the fact that modern metamorphic petrology demands an awar…
A model assuming a non-continuous structure of glasses is established to interpret the inelastic neutron scattering and Raman scattering. The 'boson' peak in Raman scattering is related to the vibrational density of states 'excess'. These two related features are a result of vibrations localized in the blobs that comp…
The authors have formulated a polarized-orbital treatment of electron-atom scattering which includes dynamic distortion effects. Detailed formulae are given in terms of their previous formulation of the polarized-orbital method. Results for electron-helium scattering are presented and compared with various experimenta…
Using mechanical alloying and a subsequent two-step heat treatment we produced magnetically isotropic microcrystalline Sm2Fe17Nx samples with room-temperature coercivities up to 24 kA/cm (30 kOe). The remanence and the energy product are equivalent to similarly prepared Nd-Fe-B samples, but the properties at elevated…
A simple and accurate extended Jones matrix representation for the twisted nematic liquid-crystal display at the oblique incidence was obtained for the first time. The results obtained by this extended Jones matrix representation are quite close to those obtained by the faster 4×4 matrix method with spectrum averaging…
The authors propose a new method of series analysis in which the available series coefficients are fitted to an algebraic equation. Such a proposal restricts solutions to have algebraic singularities with rational critical exponents. The advantage of the method over the method of differential approximants is that in t…
Cellulose is synthesized by all higher plants as well as by a wide variety of other organisms. The amount of synthesis is enormous, making cellulose the most abundant biopolymer on earth (1 ) . Most native cellulose is found in cell walls in the form of structural micro - fib rils . Although considerable effort has go…
The crystal structure of perlialite from the Murun Massif, U.S.S.R. was determined and refined using synchrotron X-ray powder data. The framework type of this natural zeolite is the same as synthetic zeolite Linde-L. Extraframework cation and water oxygen position were located, and the locations and occupancies show l…
After cooling below 80 K a considerable amount of diffuse scattering is observed in Li, in addition to 9R and fcc Bragg reflections. The diffuse scattering localized on the [101] line of the 9R reciprocal lattice is modulated along this line indicating a short-range order in the stacking sequence of the close-packed p…
Raman measurements were carried out on Ge quantum dots from 6.1 to 15 nm in size embedded in SiO2 thin films. The samples were prepared by rf co-sputtering and post- annealing. In contrast to the amorphous-like broad spectra previously obtained for gas- evaporated Ge microcrystals of comparable sizes, relatively sharp…
Nanometer-size diamond particles formed on a silicon substrate by the hot-filament chemical vapor deposition method were examined by a high-resolution electron microscope. The particles developed well-faceted cuboctahedral habits. Examination of their morphologies and microstructures provides a wealth of information o…
The ionic polarizabilities in Pb(ZrxTi1−x)O3 compositions are calculated by the Clausius-Mossotti-Lorentz-Lorentz equation. The resultant gap of the polarizability appearing at the morphotropic phase boundary (MPB) composition suggests the phase transition boundary to be due to the electrostatic long-range dipole mome…
The fluorescence spectrum of tripositive americium in a fluorozirconate glass at low temperature has been measured. Six fluorescence lines were observed between 515 to 880 nm and identified as Am3+ transitions. Fluorescence decay measurements at 15 K are reported for transitions that originate from states 5D1′ (∼1.0 m…
X-ray-diffraction patterns, macroscopic compressibility, and crystallization in amorphous Se subject to pressure have been investigated. The material exhibits pressure-induced structural modifications in the glassy state and a phase transformation to the hexagonal phase at 120\ifmmode\pm\else\textpm\fi{}20 kbar. The o…
The polarized memory effect, in which the switching between the on and off states depends on the polarity of the bias voltage, was found in the device including the film of the organic charge-transfer complex, copper-tetracyanoquinodimethane (Cu-TCNQ). The device consists of three layers, Al/Cu-TCNQ/Cu. The dc I-V cha…
A generalization of the well-known Flory and Flory–Huggins mean-field approximations to the equation of state is derived for a three-dimensional lattice model in which a monomer occupies an entire unit cell, and many bond lengths and bond angles are possible. By measuring the probability for particles to be in contact…
The energies of the two energetically lowest dipole-allowed electron-hole-pair states in semiconductor microcrystallites are computed variationally. Details of the quantum confinement conditions, such as the finite value of the quantum confinement potential and the different effective electron-hole masses inside and o…
C 14 H 8 S 4 + •I 3 − (I) cristallise dans C2/m avec a=19,831, b=9,266, c=14,515 A, β=90,03 o , Z=6; affinement jusqu'a R=0,0434. C 14 H 8 S 4 + •Cu(NCS) 2 − (II) cristallise dans P1 avec a=8,390, b=9,667, c=12,699 A, α=95,07, β=108,25, γ=112,50 o , Z=2; affinement jusqu'a R=0,142. Dans (I), les ions dibenzotetrafulva…
The magnetic permeability of stoichiometric or non-stoichiometric magnetite (Fe 3- y O 4 ) at high pressures has been measured in a piston-cylinder apparatus. The Verwey transition temperature decrease with pressure at rates of 2.7±0.1 KGPa -1 for y =0.000, 2.49±0.07 for y =0.0051, 2.3±0.1 for y =0.0063, 2.55±0.03 for…