Materials Literature
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ADVERTISEMENT RETURN TO ISSUEPREVCommunicationNEXTThe First Isolation and Characterization of a Palladium−Copper Heterometallic Complex Bearing μ4-Oxo Atom Derived from Molecular OxygenTakahiro Hosokawa, Minoru Takano, and Shun-Ichi MurahashiView Author Information Department of Chemistry, Faculty of Engineering Scien…
The stepwise syntheses and characterization of a series of symmetrical and unsymmetrical bisporphyrins, bischlorins, and biscorroles, and of porphyrin−chlorin and porphyrin−corrole dyads possessing ethylene, phenyl, and stilbene linking units are described. The methodology for synthesis of 10-substituted corroles 2 an…
ADVERTISEMENT RETURN TO ISSUEPREVCommunicationNEXTInteractions between Organized, Surface-Confined Monolayers and Vapor-Phase Probe Molecules. 10. Preparation and Properties of Chemically Sensitive Dendrimer SurfacesMona Wells and Richard M. CrooksView Author Information Department of Chemistry, Texas A&M University C…
Solid-state polymer light-emitting electrochemical cells have been fabricated using thin films of blends of poly(1,4-phenylenevinylene) and poly(ethylene oxide) complexed with lithium trifluoromethanesulfonate. The cells contain three layers: the polymer film (as the emissive layer) and indium-tin oxide and aluminum f…
Quasi-one-dimensional CaF2 islands, 5–10 nm in both width and height and several μm in length, have been grown on Si(001) by molecular beam epitaxy. Using conventional and high resolution transmission electron microscopy we show that the islands grow in two symmetry-equivalent, {011} orientations and are bounded by {1…
Diamond nucleation on mirror-polished Si was enhanced by electron emission using hot filament chemical vapor deposition. The nucleation density was 108 cm−2. The mechanism of diamond nucleation is carefully discussed. It is surmised that it is electron emission that is responsible for the enhancement of the diamond nu…
The plane-wave pseudopotential approach to the density-functional theory (DFT) in the local-density approximation (LDA) is used for an ab initio calculation of pressure-dependent structural, lattice-dynamical, and dielectric properties of cubic silicon carbide (3C SiC). Whereas the influence of hydrostatic pressure on…
In zero field, shows thermally activated behaviour for all values of x. For charge ordering occurs at 250 K, with long-range antiferromagnetic ordering at lower temperatures. For a range of compositions a first-order magnetic-field-induced insulator - metal transition produces changes in resistivity of up to 12 orders…
A pulsed anodic etching method is developed to prepare light-emitting porous silicon. Under the same equivalent etching condition, pulsed etching can yield a more uniform porous silicon film with stronger photoluminescence intensity than the film prepared by ordinary dc etching. The atomic force microscopic observatio…
We report about the observation of intrinsic optical bistability of nanometer-size spherical CdS particles coated with silver. The particles were chemically prepared as isolated CdS clusters in aqueous suspensions and coated with silver by chemical reduction from added AgNO3. They exhibit intrinsic optical bistability…
Two different crystal forms of the 9 kDa protein of the signal recognition particle (SRP9) have been prepared by the hanging drop vapor diffusion technique using 28% (w/v) PEG8000 or 28% saturated ammonium sulphate as precipitant. The crystals are hexagonal bipyramids with average dimensions of 0.2 X 0.1 X 0.1 mm(3) a…
Polyaniline films prepared via the camphorsulphonic acid (CSA)m-cresol solution processing route have been synthesized with doping levels in the range of 10 - 90%. The electrical conductivity of these films has been measured as a function of temperature between 10 and 300 K. At a doping level of 30% the onset of metal…
The optical excitations in $\rug$ and higher fullerenes, including isomers of C$_{76}$, C$_{78}$, and C$_{84}$, are theoretically investigated. We use a tight binding model with long-range Coulomb interactions, treated by the Hartree-Fock and configuration-interaction methods. We find that the optical excitations in t…
Charge-transfer (CT) exciton effects are investigated for the optical absorption spectra of crosslinked C60 systems by using the intermediate exciton theory. We consider the C60-dimers, and the two (and three) molecule systems of the C60-polymers. We use a tight-binding model with long-range Coulomb interactions among…
Competition between the ferromagnetic double-exchange interaction and the antiferromagnetic charge-ordering instability gives rise to thermally as well as magnetic field (H) induced insulator-metal transitions in distorted perovskites $({\mathrm{Nd}}_{1\ensuremath{-}y}{\mathrm{Sm}}_{y}{)}_{1/2}{\mathrm{Sr}}_{1/2}{\mat…
The large-magnetoresistance compounds ${\mathrm{La}}_{1\ensuremath{-}x}{\mathrm{Ca}}_{x}{\mathrm{MnO}}_{3}$ have been studied using specific heat, sound velocity $(v)$, and electron diffraction. For $0.63\ensuremath{\le}x\ensuremath{\le}0.67$ charge ordering is observed at 260 K and accompanied by a dramatic $(>10%…
Transparent zinc oxide (ZnO) films has been cathodically deposited on conductive glasses from a simple aqueous zinc nitrate electrolyte kept at 335 K. ZnO films prepared had a wurtzite structure and exhibited an optical band gap energy of 3.3 eV which is characteristic of ZnO. A 2-μm-thick ZnO film with an optical tra…
The macroscopic four-wave mixing susceptibility is separated into a geometrical and a molecular factor using vector coupling algebra. The geometrical factor for isotropic samples is given explicitly for collinear circularly polarized beams and for an arbitrary geometry of linearly polarized beams. The result for four…
We examine sequences of dense packings of $n$ congruent non-overlapping disks inside a square which follow specific patterns as $n$ increases along certain values, $n = n(1), n(2),... n(k),...$. Extending and improving previous work of Nurmela and Östergård where previous patterns for $n = n(k)$ of the form $ k^2$, $…
Alcaligenes latus, a growth-associated PHB producer, was cultivated by a pH-stat modal fed-batch culture technique to attain high PHB productivity. Both sucrose solution and inorganic medium were fed in conjunction with the supply of ammonia solution which serves as a nitrogen source and as a means of pH control. Comp…