Materials Literature
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In this paper the statistical mechanical properties are investigated of a simple analytical model which is based loosely on a cluster of atoms. The model has a phase transition from a solid-like to a liquid-like phase. Particular interest is paid to the dependence of the nature of this phase transition on the number o…
The morphology of epitaxial structures formed in solidification of liquid Au films on the Au(110) surface was studied by molecular dynamics simulation based on a many--body interatomic potential. The (1x2) reconstructed and smooth phase at the temperature T=500 K, as well as a deconstructed and rough phase of the Au(1…
Abstract Electrically conductive polypyrrole (PPy)/poly( p ‐phenylene terephthalamide) (PPTA) composite fibers have been prepared by continuous vapor phase polymerization at a speed of 0.5 ∼ 1.5 m/min. The main parameters have been examined, and the conducting fibers with the best properties of electrical conductivity…
Abstract Blends of polycarbonate (PC) with poly(butylene terphthalate) (PBT) were characterized using density measurements, DSC, IR, and TGA. Addition of PBT increases the density values of blends linearly. All the blends show a single glass transition temperature, indicating the miscibility of the two polymers in the…
Abstract To establish relationships among the blend composition, processing history, and the resultant properties of starch‐based thermoplastics, three varieties of corn starch: (1) Waxy Maize, (2) Native Corn, and (3) high‐amylose Hylon VII were extrusion‐blended with poly(ethylene‐vinyl alcohol) (EVOH) containing 56…
Abstract Viscosity and density of homogeneous one‐phase solutions (1 wt %) of polyethylenes with narrow molecular weight distributions ( M w = 2150, 15,520, 108,000, and 420,000) in n ‐pentane were determined at 398, 413, and 428 K over a pressure range from 20 to 60 MPa. Measurements were done with a special falling…
The use of molecular genetics to introduce both a metal ion binding site and a nitroxide spin label into the same protein opens the use of paramagnetic metalnitroxyl interactions to estimate intramolecular distances in a wide variety of proteins. In this report, a His-Xaa3-His metal ion binding motif was introduced at…
Mercury has perhaps the strangest behavior of any of the metals. Although the other metals in column IIB have an $hcp$ ground state, mercury's ground state is the body centered tetragonal $β$Hg phase. The most common phase of mercury is the rhombohedral $α$Hg phase, which is stable from 79K to the melting point and me…
We study the antiferromagnetic phase of the C60-polymer doped with one electron per one C60 by using a tight-binding model with long-range Coulomb interactions. The model is solved by the unrestricted Hartree-Fock approximation, and a phase diagram is obtained by changing Coulomb interaction strengths and a conjugatio…
We calculate the consequences of molecular exchange between two states with different relaxation rates in dielectric spectra. In a critical range where exchange rates are of the order of the relaxation rates, both individual processes show apparently increased relaxation frequencies, and the slower process gains inten…
The surface structures of homoepitaxial diamond (001) films have been studied by using scanning tunneling microscopy. Boron-doped films were grown on natural diamond substrates. Images showed a dimer-type 2×1 reconstruction with well-resolved dimers. The surface consists of alternating terraces of 2×1 and 1×2 dimeriza…
By using the mass-analyzed low energy dual ion beam deposition technique, a high quality epitaxial, insulating cerium dioxide thin film with a thickness of about 2000 Å has been grown on a silicon (111) substrate. The component species, cerium and oxygen, are homogeneous in depth, and have the correct stoichiometry fo…
The thermalization of electrons in copper nanoparticles embedded in glass is investigated using femtosecond pump-probe spectroscopy. The time dependent induced transmission is enhanced near the surface plasmon resonance of the nanoparticles, as opposed to the static one obtained with thermomodulation measurements. In…
Pr 3 (SiO 4 ) 2 Cl is isostructural with La 3 (SiO 4 ) 2 Cl. The Pr(1)O 7 Cl polyhedron is irregular. The Pr(2)O 8 Cl 2 polyhedron is a distorted square antiprism with the Cl atom capping distorted square faces. The site of Pr(2) can also be described as at the centre of a Pr(2)(SiO 4 ) 4 Cl 2 octahedron. The structur…
We present the results of detailed electrical measurements on diamond films grown by hot-filament chemical-vapor deposition. Two different mixtures of reaction species, hydrogen/methane and hydrogen/acetone, were utilized to grow diamond films. The latter is useful for introducing dopants during growth in a relatively…
Poly(3-hydroxybutyrate) (PHB)-negative mutants of Bacillus megaterium were isolated following mutagenesis with N-methyl-N′-nitro-N-nitrosoguanidine. Different strategies were used for isolation, including ultracentrifugation through sucrose gradients and selection for resistance to allyl alcohol. The mutants were dete…
Distannoxane complexes catalyze the ring-opening polymerization of optically active β-butyrolactone (β-BL) to afford a high molecular weight poly(3-hydroxybutyrate). When 1-ethoxy-3-chlorotetrabutyldistannoxane was used as a catalyst (catalyst/(R)-β-BL = 1/8000 at 100 °C for 4 h), poly((R)-3-hydroxybutyrate) was obtai…
Parallele Schichten aus Fe‐ und O‐Atomen charakterisieren den Clusterkern des zehnkernigen Fe III ‐Komplexes 1 (dbm = Dibenzoylmethan), der durch kontrollierte Hydrolyse aus FeCl 3 entsteht. Die O‐Atome in 1 bilden dabei in Analogie zu denen in einigen Eisenoxiden und ‐hydroxiden eine kubisch dichteste Packung. Die sc…
The structure consists of layers of Ag(CN) 2 - ions arranged in such away that trigonal prisms of N atoms are formed. Each prism is occupied by an Eu 3+ ion, to which three H 2 O molecules coordinate and complete the tricapped trigonal geometry.
Polarized properties of both the singlet and triplet ground exciton states in the photoluminescence and transmission spectra of crystalline GaTe are explained based on the possible symmetry properties of the energy band edge of GaTe. Some experimental results about excited exciton states in GaTe are presented and disc…