Materials Literature
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A kinetic and ligand binding study on maize (Zea mays) malate synthase is presented. It is concluded from kinetic measurements that the enzyme proceeds through a ternary-complex mechanism. Michaelis constants (Km,glyoxylate and Km,acetyl-CoA) were determined to be 104 microM and 20 microM respectively. C.d. measuremen…
We report results for photoluminescence studies of an impurity-related defect system in 450 \ifmmode^\circ\else\textdegree\fi{}C annealed Czochralski-grown silicon resulting in optical emission with a wavelength near 1.7 \ensuremath{\mu}m. The photoluminescence emission is found to have a significant intensity that pe…
Medium-energy ion-scattering measurements and Monte Carlo simulations have been used to study the Al(001) surface as a function of temperature. Surface melting does not occur and the surface stays well ordered up to the bulk melting point ${\mathit{T}}_{\mathit{m}}$=933.52 K. The combination of the effective-medium po…
The electronic and the optical properties of \ensuremath{\beta}-${\mathrm{C}}_{3}$${\mathrm{N}}_{4}$ are studied by means of first-principles local-density calculations. The structural properties obtained via total-energy calculations are in good agreement with the results of Liu and Cohen [Phys. Rev. B 41, 10727 (199…
Various structural possibilities for the Si2C4 and Si4C2 clusters are investigated by employing a basis set of triple-zeta plus polarization quality; electron correlation is generally accounted for by second-order Mo/ller–Plesset and, in certain instances, by higher-order perturbation (CASPT2) approaches. The building…
Molecular dynamics simulations have been performed for the nematic liquid crystal 4-n-pentyl-4′-cyanobiphenyl (5CB) using a realistic atom–atom potential as well as a pseudorealistic atom–atom potential. The latter treats the phenyl rings in the 5CB molecule as simple spheres. This method allows a considerable decreas…
Analyses of high-resolution synchrotron X-ray powder diffraction patterns of dry-synthesized MFemSi206 leucites (M = K, Rb, Cs) showed that the K-and Rbcontaining leucites (iron potassium silicate, KFeSi206, and iron rubidium silicate, RbFeSi206) each have a tetragonal 141/a structure and the Cs-containing leucite (ca…
We report Hall-effect measurements on single crystals of antiferromagnetic pyrite-type ${\mathrm{NiS}}_{2}$ (${\mathit{T}}_{\mathit{N}}$=40 K), in which the resistivity appears to show a metal-insulator transition at T\ensuremath{\approxeq}100 K. Our transport measurements demonstrate that this transition is not intri…
We have studied the electronic properties of the Cu/${\mathrm{TiO}}_{2}$(110) and Fe/${\mathrm{TiO}}_{2}$(110) interfaces using in situ ultraviolet photoemission spectroscopy (UPS) and inverse photoemission spectroscopy (IPS). The chemical interaction between these two transition metals and the substrate was monitored…
Nanometer size crystalline particles of α-Fe, γ-Fe, Ni, β-Co, and Co3C encapsulated in multiwalled carbon cages are synthesized by a standard dc arc evaporation of composite anodes containing 10–15 wt. % each of the metals or their compounds. The typical particle size is ∼10 nm. Elemental analysis is made by x-ray ene…
In this paper we give a description of the doping dependence of the $\mathrm{Ni} 2p$ x-ray-absorption spectra of ${M}_{x}{\mathrm{Ni}}_{1\ensuremath{-}x}\mathrm{O}$ ($M=\mathrm{L}\mathrm{i},\mathrm{N}\mathrm{a}$). We will show that a description beyond an atomic-multiplet calculation is required. To study intermediate…
Barium titanate thin films were fabricated by the sol-gel technique from two different precursors, one using barium 2-ethyl haxanoate and other using barium hydroxide dissolved in methoxy ethanol as barium source. The films were examined at different curing temperatures using Fourier transform infrared (FTIR) spectros…
We perform ab initio molecular-dynamics simulations using the higher-order finite-difference-pseudopotential (FDP) method to calculate the interatomic forces. Our approach is compared to molecular-dynamics-simulation calculations where the forces are calculated using a plane-wave basis. The ground-state structures of…
Hot-stage high-voltage (1.5 MeV) transmission electron microscopy was used to directly observe CdS nanocrystals precipitated in a silicate glass and a theoretical framework of nanocrystal coarsening kinetics more appropriate than the popularly used Lifshitz–Slyozov–Wagner theory was developed. Nanocrystallite nucleati…
Mechanisms of stability of foams with and without oil are presented in this chapter based on the structure and stability of the thin liquid films (foam lamellae). The drainage and stability of single-foam lamellae and bulk foams depend on the surfactant concentration. At low surfactant concentrations, the drainage of…
A model of electron transport in alkali halides, below 10 eV, is described. It is based on theoretically calculated microscopic cross sections of electron interactions with lattice phonons. Both acoustic and optical scatterings are taken into account, the former being also treated as a quasielastic process that random…
The 4f electronic state and the decay process of the photoexcited 4${\mathit{d}}^{9}$4${\mathit{f}}^{\mathit{n}+1}$ states in ${\mathrm{CeO}}_{2}$ are investigated by means of a resonant photoemission technique in the Ce 4d\ensuremath{\rightarrow}4f photoabsorption region. Resonant enhancement of the valence-band emis…
The Stark effect on the electronic absorption spectrum of CdSe nanocrystals has been studied for nanocrystals ranging in size from 80 to 20 Å in diameter. For all but the smallest clusters, a second derivative line shape is observed, indicative of a dipole moment in the excited state. This result is independent of the…
The densification behavior, microstructure, and electrical properties of ZnO-V2O5 ceramics were studied with V2O5 as the only additive ranging from 0.01 to 1.0 mol %. The addition of V2O5 to zinc oxide shows a tendency to enhance the densification rate and promote grain growth. However, a microstructure that consisted…
Abnormal (100) grain growth has been characterized in predominantly (111)-textured Cu thin films as a function of deposition temperature, annealing temperature and the presence of a Ta or W underlayer. For films deposited at room temperature, bimodal grain size distributions are observed at annealing temperatures at o…