Materials Literature
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Diffraction properties of an amplitude liquid crystal grating with a periodic electrode structure are studied under different polarizer configurations. Based on these experimental results, polarization characteristics of light diffracted from this grating are discussed. Both diffraction light intensities and polarizat…
The structure of the inorganic misfit layer compound (La 0.95 Se) 1.21 VSe 2 has been determined on the basis of a four-dimensional superspace group. The crystal is composed of an alternate stacking of VSe 2 sandwiches and two-atom-thick LaSe layers. The first subsystem VSe 2 has a distorted CdI 2 -type structure with…
Novel properties of recently developed conducting and insulating polymers and their composites are discussed. Properties of conducting polymer whose main chains are composed of unsaturated /spl pi/-bonds depend strongly on the main chain structure, substituent and also molecular dopants. Various applications of conduc…
We use the cathodoluminescence mode of a scanning electron microscope to investigate the depth and lateral dependencies of the electron-hole pairs generation by the electron beam in Al0.4Ga0.6As semiconducting material. A multiquantum well structure acts as a detector to measure the relative number of generated minori…
Magic-angle-spinning (MAS) deuterium NMR of ${\mathrm{YD}}_{\mathit{x}}$, x\ensuremath{\sim}2, yields spectrally resolved lines for D atoms in tetrahedral (T) and octahedral (O) interstitial sites. Compared to MAS line narrowing of metal hydrides, the deuterides line narrow with only modest, readily attainable spinnin…
The thermal conductivities of two polycrystalline diamond films made by chemical-vapor-deposition process have been measured from a temperature of 15–550 K by using a standard steady-state technique. While one of the samples was of natural abundance composition (98.9% 12C and 1.1% 13C) the second sample was composed o…
Abstract The second‐order elastic constants C 11 , C 12 , and C 44 , isothermal bulk modulus B T , and volume thermal expansion coefficient α are calculated for NaCl crystals in the temperature range (294 to 766 K) using Tallon's model based on the concept of modified Anderson‐Grüneisen parameters. The results obtaine…
Abstract The results of ab initio and MNDO calculations of the Cl 2 C = CHOCH 3 , XCOCl (X = CH 3 , OCH 3 and COCl), 4-ClC 6 H 4 CH 2 Cl, (CNCl) 3 and PCl 5 with total optimization of their geometry are presented. The ab initio calculations were executed using Hartree-Fock theory and the split valence basis set 6-31G*…
Anodic oxides of thickness 1–10 nm have been grown on Si(100) using anodic oxidation at room temperature. The electrolyte was 0.1 M HCl. The effects of the anodic potential, growth time, external visible illumination intensity, substrate doping type, and density on the oxide thickness were determined. Coulometric and…
Electrical transport and the nature of carriers in the homovalent substitution LLaFe x Ni1–x O3 were investigated as a function of component, in the temperature range 10K–300K, by dielectric properties, dc and ac conductivities and thermopowers. At x > 0·6, the positive thermopowers indicate the major carriers of hole…
Mechanochemistry of hydrothermally prepared Al‐free and Al‐substituted 1.1 nm tobermorite was studied using 29 Si NMR, XRD, and TGA‐DTA. Tobermorite has a double‐chain structure and Al/Si substitution occurs preferentially at bridging tetrahedra. By using the vibration mill, both tobermorites were observed to decompos…
Summary Laboratory experiments were carried out to evaluate the effect of pH, ionic strength and electrolyte composition on zinc sorption–desorption by two Andepts from the Canary Islands (Spain). At the natural soil pH, the soils exhibited little net negative surface charge and small Zn sorption capacities. More than…
The dynamical properties of binary liquid mixtures are investigated within a viscoelastic model using the memory function approach. Extending the viscoelastic model to the binary case we find that the dynamical properties of the liquid mixture are characterized by four propagating and two diffusive modes. We show that…
Abstract Hydrogen- (δD = −106 to −97‰) and oxygen-(δ 18 O = +14.0 to +16.6‰) isotope compositions of kaolinite from late Cretaceous and Oligocene deposits at Iwaizumi, northeastern Japan, indicate that these clays formed by weathering of volcanic parent rocks, rather than during hydrothermal (>100 °C) alteration. T…
The strain energy per unit area for a deformed sheet of elastic material is estimated by representing the deformation as a power series in the thickness variable. The <italic>membrane</italic> energy is the lowest-order approximation obtained in this way. Strain-gradient and bending energies appear in the next order o…
Transparent mullite fibers have been prepared using aluminum carboxylates (ACs) and tetraethyl orthosilicate (TEOS) as starting materials. The ACs are derived from the catalyzed dissolution of elemental aluminum in a mixture of formic acid and acetic acid. The solubility of aluminum in the acids is influenced by the c…
Abstract Thin melt crystallized spherulitic films of isotactic polypropylene have been deformed in uniaxial tension at different temperatures and examined by transmission electron microscopy. As the temperature was increased above approximately −80°C, a transition from high aspect ratio craze‐like features to highly v…
Thermal and mechanical behavior of high power ZnO surge arresters under current pulses of various magnitude and duration is simulated. By solving heat transfer equations for a varistor disk with nonuniform electrical properties, we compute the time dependence of the temperature profile and the distribution of thermal…
Abstract An A–B–A triblock copoly(ester-ether) comprising poly(l-lactide) (A) and poly(oxyethylene-co-oxypropylene) (B) was prepared by copolymerization of l-lactide and a commercially available telechelic copolyether, Pluronic® (PN), with different molecular weights by the catalysis of tin(II) octanoate. The low mole…
Scanning tunneling microscopy (STM) was used to investigate the reaction of carbon monoxide with atomic oxygen on Cu(110) in the steady state at 150 K. Oxygen dosed at 150 K reacts with copper atoms on the terraces to form CuO pseudomolecules 2–7 units long, in contrast to oxygen dosed at 300 K which forms long Cu…