Materials Literature
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${}^{30}\mathrm{Si}$ diffusion was measured in quartz along c axis in the $\ensuremath{\beta}$-phase field, at $T\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}1400$-- $1600\ifmmode^\circ\else\textdegree\fi{}\mathrm{C}$ by Rutherford backscattering spectrometry and the ${}^{30}\mathrm{Si}(p,\ensuremath{\gamma})^{3…
The role of externally-controlled chemical reactions in the selection of patterns in phase-separating mixtures is presented. Linearized theory and computer simulation show that the initial long-wavelength instability characteristic of spinodal decomposition is suppressed by chemical reactions, which restrict domain gr…
Electroluminescence is obtained from nearly monodisperse CdSe nanocrystallites (quantum dots) incorporated into thin films (1000 Å) of polyvinylcarbazole (PVK) and an oxadiazole derivative (t-Bu-PBD) and sandwiched between ITO and Al electrodes. The electroluminescence and photoluminescence spectra (bandwidths ≤40 nm)…
A numerical study is presented of the motion of two-dimensional, doubly periodic, dilute and concentrated emulsions of liquid drops with constant surface tension, subject to a simple shear flow. The numerical method is based on a boundary integral formulation that employs a Green's function for doubly periodic Stokes…
The Jones matrix is obtained for a film with a photoinduced anisotopy. The anisotropy of the film is considered to be caused by photoinduced anisotropic grains. On the basis of the Jones matrix we study Weigert's hologram of linearly polarized plane waves.
A simple preparation of Cd(17)S(4)(SCH(2)CH(2)OH)(26) clusters in aqueous solution leads to the formation of colorless blocky crystals. X-ray structure determinations revealed a superlattice framework built up of covalently linked clusters. This superlattice is best described as two enlarged and interlaced diamond or…
A new tight-binding total energy method, which has been shown to accurately predict ground state properties of transition and noble metals, is applied to Manganese, the element with the most complex ground state structure among the $d$ metals. We show that the tight-binding method correctly predicts the ground state s…
We study the early-stages of ordering in $Cu_3 Au$ using a model Hamiltonian derived from the effective medium theory of cohesion in metals: an approach providing a microscopic description of interatomic interactions in alloys. Our simulations show a crossover from a nucleated growth regime to a region where the order…
Exciton effects on soliton and bipolaron lattice states are investigated using an electron-lattice Peierls model with long-range Coulomb interactions. The Hartree-Fock (HF) approximation and the single-excitation configuration-interaction (single-CI) method are used to obtain optical absorption spectra. We discuss the…
Abstract We have shown liquid crystals to be members of the more general class of helicoidal bianisotropic mediums (HBMs) and have discussed physical realizations of HBMs as liquid crystals, cross-linked polymer networks and solid thin films. Solutions of the time-harmonic Maxwell postulates for axial propagation in a…
Abstract A novel polymer processing technique known as elastic strain pulverization (ESP) involves the simultaneous effects of high pressure and shear deformation to pulverize polymers. Homopolymers and blends of commercially important postconsumer plastics, including high‐density and low‐density polyethylene (HDPE, L…
Transmission electron microscopy has been used to characterize the large solvent‐stabilized palladium clusters with uniform size distribution that are formed in homogeneous Pd II ‐catalyzed oxidations in dimethyl sulfoxide.
On the basis of the available high-resolution structures of mandelate racemase (MR) from Pseudomonas putida [Landro, J. A., Gerlt, J. A., Kozarich, J. W., Koo, C. W., Shah, V. J., Kenyon, G. L., Neidhart, D. J., Fujita, J., & Petsko, G. A. (1994) Biochemistry 33, 635-643], Lys 166 and His 297 are positioned appropriat…
In the high-resolution X-ray structure of mandelate racemase (MR) with the competitive inhibitor (S)-atrolactate bound in the active site [Landro, J. A., Gerlt, J. A., Kozarich, J. W., Koo, C. W., Shah, V. J., Kenyon, G. L., Neidhart, D. J., Fujita, J., & Petsko, G. A. (1994) Biochemistry 33, 635-643], the carboxylic…
Structural features of the heavier and lighter homologues of tellurium are embodied in the two partial structures of Cs3Te22: crown-shaped Te8 rings, which are stabilized in the coordination sphere of a cesium cation (shown on the right), are similar to analogous S8 and Se8 rings, whereas the layer anions [Te4Te] may…
A hypervalent, one-dimensional polymer with interlocking zigzag chains (shown on the right) is obtained in the reaction of diiodoacetylene with tris(dimethylamino)cyclopropenylium iodide. The formation of the first stable 1:1 adduct from I− ions and a compound with Csp-bonded I centers is attributed to strong n → σ* i…
The lumazine synthase/riboflavin synthase complex of Bacillus subtilis consists of an icosahedral capsid of 60 beta subunits surrounding a core of 3 alpha subunits. The beta subunits catalyze the condensation of 5-amino-6-ribitylamino-2,4(1H,3H)-pyrimidinedione with (3S)-3,4-dihydroxy-2-butanone under formation of 6,7…
The structural changes in Pd and Pd–Ru alloys induced by the repeated absorption–desorption of hydrogen have been studied. It is found that absorption–desorption cycles produce structural changes in Pd whereas the addition of small amounts of Ru inhibits these hydrogen-induced changes. The experimental results show th…
We consider the shear flow of well-aligned one-component smectic phases, such as thermotropic smectics and lamellar diblock copolymers, below the critical region. We show that, as a result of thermal fluctuations of the layers, parallel $\left(c\right)$ alignment is generically unstable and perpendicular $\left(a\righ…
The evolution of microstructure in Al and Cu thin film lines during electromigration has been studied using a transmission electron microscopy. Grain boundary migration was found to be critically involved in the electromigration induced hillock formation that can be described as a three-dimensional growth of a single…