Materials Literature
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Biaxial stress and strain in (100) and (111) oriented grains have been measured as a function of annealing temperature for a Cu film on an oxidized Si substrate which exhibits abnormal (100) grain growth. The observed behavior indicates isostrain averaging, which is consistent with grain growth that is controlled by s…
We determined the phase diagram of a binary hard-sphere dispersion with size ratio 9.3. Phase separation into a fluid and a crystal of large spheres is observed. The fluid-solid binodal is determined by measurements of compositions of coexisting phases. The results agree qualitatively with recent theories, although th…
A theory for the nematic-isotropic (N-I) phase transition of prolate uniaxial molecules with longitudinal dipole moments is presented. The theory is based on the variational cluster expansion, truncated after the two-molecule term, and is implemented for polar hard spherocylinders with and without attractions, and for…
The effective diffusion coefficient, D(e), and the distribution constant, K(i), for selected mono- and disaccharides and organic acids were determined in homogeneous calcium-alginate gel with and without entrapped bacteria. Results were obtained from transient concentration changes in well-stirred solutions of limited…
The spectral dependencies of the optical rotatory power (ORP) and Verdet coefficient (V) of undoped Bi<SUB>12</SUB>GeO<SUB>20</SUB> (BGO), Bi<SUB>12</SUB>SiO<SUB>20</SUB> (BSO) and Bi<SUB>12</SUB>TiO<SUB>20</SUB> (BTO), and doped with V, Fe and Cr BSO crystals are studied. It is established that Cr and Fe strongly cha…
The lateral fixing of calamitic mesogens through hydrogen bonding of facial amphiphiles is a novel way of generating smectic materials with a broad mesomorphic region. Compound 1 is an example of this amphiphile and represents a new type of liquid-crystalline carbohydrate. R = OC10H21.
Highly selective aerobic hydroxylation of tertiary carbon centers in alkanes is catalyzed by the title polyoxometalate under mild reaction conditions [Eq. (a)]. This is of great significance, in particular in the search for ways to activate molecular oxygen in the oxidation of hydrocarbons.
Bleomycin hydrolase is a cysteine protease that hydrolyzes the anticancer drug bleomycin. The homolog in yeast, Gal6, has recently been identified and found to bind DNA and to act as a repressor in the Gal4 regulatory system. The crystal structure of Gal6 at 2.2 A resolution reveals a hexameric structure with a promin…
The successful synthesis of pure boron nitride (BN) nanotubes is reported here. Multi-walled tubes with inner diameters on the order of 1 to 3 nanometers and with lengths up to 200 nanometers were produced in a carbon-free plasma discharge between a BN-packed tungsten rod and a cooled copper electrode. Electron energy…
Lattice images as obtained by high-resolution electron microscopy are used to quantify strain and strain profiles in semiconductor layer structures. Inherent parts of the analysis are the definition of spatial resolution and detection limit on the basis of a quantification of noise. As an application the tetragonal st…
Abstract Preparation of porous carbons from phase‐inversion membranes was investigated as a control method of pore structure in carbon materials. The structure in carbon films was estimated by means of electron microscopy, mercury porosimetry, and gas‐adsorption methods. When phase‐inversion membranes of Kapton‐type p…
An experimental study of the temperature and frequency dependence (in the audio and rf and microwave regions) of the conductivity of ${\mathrm{H}}_{3}$${\mathrm{PO}}_{4}$-doped polyaniline samples is presented. The dopant concentration of the samples varies between 0.09M and 3.60M. For all the samples studied, the tem…
Persistent spectral hole-burning phenomenon in CuBr quantum dots embedded in glass was observed. The spectral hole and the sideband holes were made together with the redshift of the absorption spectrum in proportion to the logarithm of the laser fluence and were preserved for more than 8 h at 2 K. They were erasable b…
Abstract The determination of viscoelastic property variation in short fiber‐reinforced composites, as a function of strain, temperature, and frequency, constitutes a useful tool when the existence or the strength of matrix–fiber interfaces are to be examined. In this work, these properties are studied in thermoplasti…
The complex conductivity spectra of the quasi-one-dimensional compounds ${\mathrm{K}}_{0.3}$${\mathrm{MoO}}_{3}$ (blue bronze) and (${\mathrm{TaSe}}_{4}$${)}_{2}$I in the conducting phase (above ${\mathit{T}}_{3\mathrm{D}}$=183 K and 263 K, respectively, but below the mean-field temperature ${\mathit{T}}^{\mathrm{MF}}…
Abstract Aromatic polyimides derived from 2,2′‐bis(3,4‐dicarboxyphenyl) hexafluoropropane dianhydride (6FDA) and 3,3′‐ or 4,4′‐diaminodiphenylsulfone ( m ‐DDS or p ‐DDS) have been synthesized with a chemical imidization. The disappearance of amic acid groups and the appearance of imide groups are determined by IR and…
Biosynthesis of subtilisin is dependent on a 77 amino acid, N-terminal prodomain, which is autocatalytically processed to create the mature form of the enzyme [Ikemura, H., Takagi, H., & Inouye, M. (1987) J. Biol. Chem. 262, 7859-7864]. In order to better understand the role of the prodomain in subtilisin folding, we…
Using the Kondo lattice model with classical spins in infinite dimension, magnetic phase transition in the perovskite-type $3d$ transition-metal oxide (La,Sr)MnO$_3$ is theoretically studied. On the Bethe lattice, the self-consistency equations are solved exactly. Curie temperatures at the region of double-exchange fe…
Electron spin resonance and photoluminescence experiments have been performed on freshly etched and oxidized porous silicon. Results indicate the presence of oxygen-related centers (nonbridging oxygen-hole center clusters), which consist of similar core structures in as-made and oxidized porous silicon (PSi) samples.…
Optical absorption spectra corresponding to the 2 F 7/2 → 2 F 5/2 transition of Yb 3+ in YbCrO 3 were investigated under high magnetic fields. The energy positions of these spectra remarkably changed at the metamagnetic transition where the weak ferromagnetic moment of the Cr 3+ spins reverses its direction. From the…