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The Effects of Crystal Field and Temperature on the Photoluminescence Excitation Efficiency of Ce3+ in YAG

D. J. Robbins1979-09-01Journal of The Electrochemical Society

Absorption and luminescence spectra of YAG:Ce 3+ crystals have been measured at various temperatures between 4.2° and 300°K. The high resolution, low temperature spectra show resolved fine structure. Zero‐phonon transitions have been assigned and the phonon replicas correlated with lattice phonon energies. The charact…

Luminescence Properties of Advanced MaterialsSolid State Laser TechnologiesRadiation Detection and Scintillator Technologies

Zinc and Copper Solubility as a Function of pH in an Acid Soil

Murray B. McBride、J. J. Blasiak1979-09-01Soil Science Society of America Journal

Abstract Studies of the effect of pH and competing cations on Zn 2+ and Cu 2+ solubility in an acid mineral soil indicate the probable involvement of hydrous oxides of iron, aluminum, or manganese in the adsorption process. Adsorption on permanent charge sites of clays, or complexation with organic matter could not ac…

Clay minerals and soil interactionsIron oxide chemistry and applicationsMine drainage and remediation techniques

Phase Relations and Reaction Sintering of Transparent Cubic Aluminum Oxynitride Spinel (ALON)

James W. McCauley、NORMAN D. CORBIN1979-09-01Journal of the American Ceramic Society

A new isobaric, condensed phase diagram in the region of stability of cubic aluminum oxynitride spinel (ALON) along the pseudobinary AI 2 O 3 ‐AIN composition join is presented, deduced primarily from various analytical measurements and microstructural observations. It is shown that cubic aluminum oxynitride spinel me…

Advanced ceramic materials synthesisMicrowave Dielectric Ceramics SynthesisInorganic Chemistry and Materials

Image Contrast And Localized Signal Selection Techniques

A. Howie1979-09-01OpenAlex

SUMMARY A survey is made of a number of the localized signal selection methods and related techniques which may be used to improve the electron microscope image contrast from small regions of material and thereby bring the specimen resolution actually achieved somewhat closer to the electron‐optical resolution of pres…

Advanced Electron Microscopy Techniques and ApplicationsElectron and X-Ray Spectroscopy TechniquesIntegrated Circuits and Semiconductor Failure Analysis

Liquid-Crystal Lens-Cells with Variable Focal Length

Susumu Sato1979-09-01OpenAlex

Liquid-crystal cells shaped like a plano-convex lens or a plano-concave lens are prepared. The focal length can be varied from the value f e for an extraordinary ray, where the liquid-crystal cell takes a homogeneous alignment, to f o for an ordinary ray, where it takes a homeo-tropic alignment, by applying an electri…

Liquid Crystal Research AdvancementsAdvanced optical system designOptical Polarization and Ellipsometry

Effective-medium theory of conductivity and Hall effect in two dimensions

C. J. Adkins1979-08-28Journal of Physics C Solid State Physics

Symmetrical effective-medium theory is used to find the conductivity and Hall effect of a two-dimensional binary mixture. Results are given in detail in the limit of low applied magnetic field, when the expressions for the Hall coefficients simplify to linear combinations of the corresponding quantities for the compon…

High voltage insulation and dielectric phenomenaThermal Analysis in Power TransmissionSurface and Thin Film Phenomena

Structure of the Smectic-BPhase and the Nature of the Smectic-Bto -HTransition in the N-(4-n-Alkoxybenzylidene)-4′-Alkylanilines

A. J. Leadbetter、M.A. Mazid、Barbara A. Kelly 等 5 位作者1979-08-27Physical Review Letters

The phase behavior and structures of several liquid crystals of the $n\mathrm{O}.m$ (${\mathrm{C}}_{n}{\mathrm{H}}_{2n+1}\ensuremath{-}\mathrm{OPhCHNPh}{\mathrm{C}}_{m}{\mathrm{H}}_{2m+1}$) series of compounds have been established by a variety of experiments. The hexagonal close-packed layers of the ${S}_{B}$ phases…

Liquid Crystal Research AdvancementsSurfactants and Colloidal SystemsMolecular spectroscopy and chirality

Study of transition metal oxides by photoelectron spectroscopy

C. N. R. Rao、D. D. Sarma、S. Vasudevan 等 4 位作者1979-08-20Proceedings of the Royal Society of London A Mathematical and Physical Sciences

Abstract Systematics in the X-ray photoelectron spectra (X. p. e. s.) of Ti, V, Cr, Mn and Nb oxides with the metal ion in different oxidation states as well as of related series of mono-, sesqui- and di-oxides of the first row transi­tion metals have been investigated in detail. Core level binding energies, spin-orbi…

Corrosion Behavior and InhibitionCatalysis and Oxidation ReactionsElectron and X-Ray Spectroscopy Techniques

Bulk and Grain Boundary Ionic Conductivity in Polycrystalline β″- Alumina

E. Lilley、J. E. Strutt1979-08-16physica status solidi (a)

Measurements of conductance and capacitance are made on polycrystalline β″-alumina over a range of frequencies from 10 to 107 Hz and temperatures from −130 to 400 °C. The results are analyzed using complex impedance plots which exhibited a bulk and grain boundary component. Above 220 °C the resistance of the grains ex…

Ferroelectric and Piezoelectric MaterialsAdvanced ceramic materials synthesisThermal Expansion and Ionic Conductivity

Dynamic mechanical properties of poly(p-phenyleneterephthalamide) fiber

Toshio Kunugi、Hideaki Watanabe、Minoru Hashimoto1979-08-15Journal of Applied Polymer Science

The dynamic mechanical properties of poly(p-phenyleneterephthalamide) fiber were investigated. Measurements of the dynamic mechanical properties were carried out on samples of low crystallinity and low orientation over a temperature range from −100 to +500°C at a frequency of 110 Hz, at a heating rate of 5°C/min. Five…

Conducting polymers and applicationsLuminescence and Fluorescent MaterialsSynthesis and properties of polymers

Dynamics and ensemble averages for the polarization models of molecular interactions

Frank H. Stillinger1979-08-15The Journal of Chemical Physics

A family of ’’polarization models’’ has been generated for description of polarizable and deformable molecules in condensed phases. Within these models the intermolecular forces are not pairwise additive, but have a many-body component that generalizes the polarization interactions present in conventional electrostati…

Material Dynamics and PropertiesSpectroscopy and Quantum Chemical StudiesAdvanced Physical and Chemical Molecular Interactions

Further developments and applications of the Green’s function method of sensitivity analysis in chemical kinetics

Eugene P. Dougherty、Jenn-Tai Hwang、Herschel Rabitz1979-08-15The Journal of Chemical Physics

A numerical procedure is presented for implementing the Green’s function method of sensitivity analysis in chemical kinetics. The procedure is applied to three sets of chemical reactions: the Chapman mechanism for ozone kinetics, a mechanism for methane combustion and a model for formaldehyde oxidation in the presence…

Probabilistic and Robust Engineering Designnanoparticles nucleation surface interactionsThermal and Kinetic Analysis

Elliptic phase boundaries between smectic and nematic phases

D. D. Klug、E. Whalley1979-08-15The Journal of Chemical Physics

Smectic–nematic phase boundaries that resemble arcs of ellipses can be analyzed by a quadratic expansion in temperature and pressure of the change ΔG of Gibbs function. If the change of entropy or volume is known, ΔG and its first two derivatives can be determined. Data on 8OCB and mixtures of 8OCB and 6OCB and of CB9…

Liquid Crystal Research AdvancementsMaterial Dynamics and PropertiesNonlinear Dynamics and Pattern Formation

Kinetics of radiative recombination in magnesium oxide

R. T. Williams、J. W. Williams、Thomas J. Turner 等 4 位作者1979-08-15Physical review. B, Condensed matter

We report time-resolved studies of luminescence excited in nominally pure single-crystal MgO by short pulses of 500-keV electrons at sample temperatures from 10 to 500 K. The principal luminescence bands have peaks at approximately 4.9, 3.3, and 1.7 eV. The decay kinetics and spectral shift of the 4.9-eV luminescence…

Luminescence Properties of Advanced MaterialsGlass properties and applicationsPhotorefractive and Nonlinear Optics

Energy position of4flevels in rare-earth metals

Börje Johansson1979-08-15Physical review. B, Condensed matter

The energy position of the occupied and unoccupied $4f$ levels relative to the Fermi energy is studied for the rare-earth metals. This is done by treating the excited state as an impurity in an otherwise perfect crystal. This picture is first considered in the complete screening approximation. In this approximation th…

Advanced Chemical Physics StudiesNuclear Physics and ApplicationsElectron and X-Ray Spectroscopy Techniques

Effect of pressure on bonding in black phosphorus

L. Cartz、S. R. Srinivasa、Robert J. Riedner 等 5 位作者1979-08-15OpenAlex

The bond lengths and bond angles of orthorhombic black phosphorus have been determined as a function of hydrostatic pressures to 26.6(5) kbar using time-of-flight neutron powder diffraction. We show that the markedly anisotropic compression reported previously results from a large pressure-induced shortening of the va…

High-pressure geophysics and materialsBoron and Carbon Nanomaterials ResearchInorganic Chemistry and Materials

Electronic structure of polyacetylene: Optical and infrared studies of undoped semiconducting(CH)xand heavily doped metallic(CH)x

C. R. Fincher、Makiko Ozaki、Momone Tanaka 等 7 位作者1979-08-15OpenAlex

The band structure and electronic properties of pure and heavily doped polyacetylene (both as grown and stretch oriented) have been investigated by a combination of optical-absorption and -reflection measurements in the frequency range from the middle ir (0.1 eV) through the visible (4.0 eV). The absorption data are c…

Organic Electronics and PhotovoltaicsConducting polymers and applicationsTransition Metal Oxide Nanomaterials

Thermal gelation properties of methyl and hydroxypropyl methylcellulose

N. Sarkar1979-08-15OpenAlex

Aqueous solutions of methyl and hydroxypropyl methylcellulose are known to gel upon heating. These gels are completely reversible in that they are formed upon heating yet will liquefy upon cooling. The precipitation temperature, gelation temperature, and gel strength of these methylcellulose solutions were determined…

Hydrogels: synthesis, properties, applicationsbiodegradable polymer synthesis and propertiesPolysaccharides Composition and Applications

X-ray photoelectron and Auger spectroscopy study of some vanadium oxides

G. A. Sawatzky、Doeke Post1979-08-15OpenAlex

A detailed investigation of ${\mathrm{V}}_{2}$${\mathrm{O}}_{5}$, V${\mathrm{O}}_{2}$, ${\mathrm{V}}_{2}$${\mathrm{O}}_{3}$, and V metal is presented. The vanadium core lines in the x-ray photoelectron spectra are anomalously wide for ${\mathrm{V}}_{2}$${\mathrm{O}}_{3}$ and V${\mathrm{O}}_{2}$. It is shown that this…

Transition Metal Oxide NanomaterialsCatalysis and Oxidation ReactionsGa2O3 and related materials