The optical properties of anisotropically ordered solutes in cholesteric liquid crystalline mesophases
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Rare earth elements adsorption on clay minerals
The adsorption of lanthanum, dysprosium, holmium, and ytterbium on kaolinite, illite and smectite has been studied. The kaolinitic and illitic materials discriminate well between the rare earths, and indicate that there is a gradual increase in adsorption-strength from lanthanum to ytterbium. This corresponds to the v…
Grain-size and pressure effects on the dielectric and piezoelectric properties of hot-pressed PZT-5
Experimental measurements and model interpretations are given for properties of hot-pressed PZT-5 specimens with grain sizes from ∼2 to 5 μm. The dielectric and piezoelectric parameters are studied as functions of temperature, of hydrostatic pressure up to 2800 kg cm−2, of grain size and of the poling history, using a…
Thermal conductivity of copper films
The thermal conductivity of thin films of copper (400–8000 Å) has been measured in the temperature range 100–500 K. It decreases with decreasing film thickness. An electrical-thermal transport analogy has been used to calculate the size-dependent thermal conductivity of the thin copper films. The decrease of the therm…
Thermal Conductivity of the Elements: A Comprehensive Review
Abstract : This report presents and discusses the available data and information on the thermal conductivity of the elements and contains the recommended reference values resulting from critical evaluation, analysis and synthesis of the available data and information. It also gives estimated values, at least for norma…
Electron Diffraction at Multiple Slits
A glass plate covered with an evaporated silver layer of about 200 Å thickness is irradiated by a line-shaped electron probe in a vacuum of 10−4 Torr. A layer of polymerized hydrocarbon of very low electrical conductivity is formed at places subjected to high electron current density. An electrolytically deposited cop…
Chlorine, Sulfur, and Water in Magmas and Oceans
Research Article| September 01, 1974 Chlorine, Sulfur, and Water in Magmas and Oceans A. T. ANDERSON A. T. ANDERSON 1Department of Geophysical Sciences, University of Chicago, Chicago, Illinois 60637 Search for other works by this author on: GSW Google Scholar Author and Article Information A. T. ANDERSON 1Department…
Systematic study of the electrical characteristics of the ``Trichel'' current pulses from negative needle-to-plane coronas
When a negative dc voltage is applied to a needle in an electronegative gas such as atmospheric air, highly regular corona current pulses (Trichel pulses) are observed under some conditions. Systematic variation of the macroscopic experimental parameters has yielded the functional dependence of the pulse frequency, ch…
Interfacial and Surface Tensions of Polymers
Interfacial and surface tensions of polymers are important in the technology of plastics, coatings, textiles, films, and adhesives through their roles in the processes of wetting, adsorption, and adhesion. Because of experimental difficulty due to high viscosity, however, reliable measurements of these quantities were…
The seven phases of sodium niobate
Sodium niobate, NaNbO3, has seven structures belonging to the perovskite family, comprising the aristotype 1 (with the ideal perovskite structure) and six hettotypes 1 (structures with lower symmetry). The differences between them can be systematized in terms of two factors, displacement of Nb from the octahedron cent…
Raman Scattering Study of the Crystallization and Phase Transformations of ZrO 2
X‐ray diffraction, electron diffraction, and Raman scattering measurements are presented for dehydrated amorphous ZrO 2 . Although the material lacks sufficient crystallinity to diffract X rays, electron diffraction patterns indicate a microcrystallinity with a grain size of 15 to 30 A. Raman spectra characteristic of…
The diatom plankton of the Indian Ocean expedition of RV "Meteor" 1964- 1965
During the Indian Ocean Expedition of R/V "Meteor" phytoplankton samples were taken with a multiple closing net ("multinet") at 103 stations. In this material the diatoms were investigated. In all 247 taxa could be identified which belong to 242 species and 5 varieties or formae of 80 genera. Of these 1 variety, 15 sp…
Ferroelectric and antiferroelectric properties of (Na0.5Bi0.5)TiO3-SrTiO3 solid solution ceramics
Phase transitions in the solid solution Sr χ(Na 0.5Bi 0.5)l-χTiO3 have been studied by dielectric, pyroelectric and D-E characteristic measurements. An intermediate antiferroelectric phase has been observed in the composition range of 0 ⩽ χ ⩽ 0.5 of this system. These compositions undergo a ferroelectric-antiferroelec…
Catalytic Methanation
Methanation, the hydrogenation of carbon oxides to methane. has been the subject of a large number of catalytic studies during the past 70 years. In the earliest work. that of Sabatier and Senderens [l]. nickel was found to be a very efficient catalyst. Nickel is still the material of choice in most investigations of…
Infrared studies of apatites. I. Vibrational assignments for calcium, strontium, and barium hydroxyapatites utilizing isotopic substitution
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTInfrared studies of apatites. I. Vibrational assignments for calcium, strontium, and barium hydroxyapatites utilizing isotopic substitutionB. O. FowlerCite this: Inorg. Chem. 1974, 13, 1, 194–207Publication Date (Print):January 1, 1974Publication History Published online1 Ma…
Soft-mode spectroscopy: Experimental studies of structural phase transitions
This paper reviews the experimental studies of displacive phase transitions in solids. Primary emphasis is upon inelastic light scattering and neutron scattering; related infrared reflectivity measurements, as well as x-ray and EPR analyses are also summarized. Several prototype structures are considered in detail: (1…
Ductile versus brittle behaviour of crystals
A necessary criterion for brittle fracture in crystals is established, in terms of the spontaneous emission of dislocations from an atomically sharp cleavage crack. We have calculated the stability of a sharp crack against emission of a blunting dislocation for a number of crystals and crystal types in two dimensions…
Encyclopedia of Electrochemistry of the Elements
Abstract not Available.
New cholesteric liquid crystals for displays
A new optically active biphenyl compound has been synthetised. By incorporating this in certain biphenyl nematogens, a chemically/photochemically stable room-temperature cholesteric liquid crystal is produced. This is of positive dielectric anisotropy and gives the cholesteric-nematic electro-optical phase-change effe…
Dispersion of Radiative Surface Plasmons in Aluminum Films by Electron Scattering
A 75-keV electron beam with a low angular divergence (8\ifmmode\times\else\texttimes\fi{}${10}^{\ensuremath{-}6}$ rad) combined with a Wien filter spectrometer is used to examine the dispersion of radiative surface plasmons in thin oxidized aluminum films. The measurements agree with theory, provided the effect of the…