Materials Literature
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Multicomponent transparent conducting oxide films with electrical, optical, and chemical properties that varied with the composition were prepared by rf magnetron sputtering. A resistivity as low as 2.8×10−3 Ω cm was obtained for InGaO3 films prepared at substrate temperatures of room temperature and 350 °C. In deposi…
Abstract Peroxidase‐catalyzed phenol polymerization in the presence of hydrogen peroxide has been extensively studied. The process offers many advantages over the conventional chemical process to produce phenol‐based resins. The enzymatic process avoids the use of formaldehyde and results in minimal formation of by‐pr…
The importance of defects in the formation of graphitic structures such as fullerenes, nanotubes, onion-like structures, helically coiled nanotubes and hypothetical periodic structures is analyzed. The structures mentioned above can also present defects which preserve their connectivity and topology. We have calculate…
Bi 0.5 Na 0.5 TiO 3 (BNT) modified with Pb showed an increased and broadened dielectric constant and limited grain growth. Pb also lowered the first transition temperature. The phases of BNT were confirmed to be ferroelectric at room temperature which transformed to antiferroelectric above 220°C. When BNT was doped wi…
The structure determination of the glutamate dehydrogenase from the hyperthermophile Pyrococcus furiosus has been completed at 2.2 A resolution. The structure has been compared with the glutamate dehydrogenases from the mesophiles Clostridium symbiosum, Escherichia coli and Neurospora crassa. This comparison has revea…
A systematic investigation of hydrogenated amorphous substoichiometric silicon oxide films (a-SiOx: H) is presented. The a-SiOx: H films were prepared by dc magnetron sputtering and were subsequently annealed at temperatures ranging from 300 to 900°C. No formation of nanocrystals is detectable either with X-ray diffra…
Abstract It is shown that supermolecules with a tetrahedral symmetry and appropriate side‐chains exhibit liquid‐crystalline phase behaviour. The use of an optimised hydrosylation reaction allows for the synthesis of materials that have four mesogenic groups attached to a siloxane core, where the conformation and the c…
Abstract The scope of this paper is to review peroxide curing of diene elastomers. At high dicumyl peroxide loading and high curing temperature, changes in the crosslinking mechanisms were observed. Both Abstraction of allylic hydrogen and addition to the double bond can act as mechanisms of crosslinking. IR spectrosc…
Single-crystal high-pressure X-ray diffraction studies on the protein crystals of orthorhombic and tetragonal hen egg-white lysozyme polymorphs were carried out using a Merrill-Bassett diamond-anvil cell, image-plate detector and synchrotron radiation. The orthorhombic crystal has been squeezed to 85.5% of its ambient…
The oxidation of irradiated Chernobyl nuclear fuel at 670 to 1170 K for 3 to 21 h resulted in its destruction into fine particles, the dispersal composition of which is well described by lognormal distribution regularity. The median radius of the formed particles does not depend on the annealing temperature and decrea…
ZnGa2O4:Mn thin films as the emitting layer in thin-film electroluminescent (TFEL) devices have been prepared by rf magnetron sputtering and low-pressure chemical vapor deposition (CVD). The as-deposited thin films, regardless of preparation methods, were ZnGa2O4 which crystallized with a spinel structure. A green EL…
Indium tin oxide (ITO) is a transparent conducting oxide used in a variety of optoelectronic applications. In order to optimize the electrical conductivity of ITO thin films it is necessary to determine this property as a function of optimum electron concentration (e.g., doping of In2O3 with Sn). A new software progra…
For ferroelectrics with a first-order phase transition, the contribution of surface to the free-energy expression was examined using transverse Ising model with four-spin interactions taken into consideration. It was shown that a ${P}^{4}$ term should be added to the surface term in the free-energy expression. The sur…
Both fine grain sized and coarse grain sized alumina has been used as a model material to correlate short crack R ‐ curves by the surface‐flaw‐in‐flexure method with long crack R ‐curves from a compact tension specimen. The analysis has been made using the crack opening displacement from long cracks combined with the…
Chemical-vapor-deposited diamond layers of thickness between 0.1 and 5 μm have the potential to improve conduction cooling in electronic microstructures. However, thermal conduction in these layers is strongly impeded by phonon scattering on defects, whose concentrations can be highly nonhomogeneous, and on layer boun…
The structure sensitive reaction, CO+NO, has been studied on two crystal planes of palladium. The Pd(111) surface was found to be approximately five times more active than Pd(100) for NO reduction by CO. This structure sensitivity is attributed primarily to the stabilization of molecularly adsorbed NO (NOa) relative t…
This article describes the synthesis and characterization of new liquid crystalline thermosets having a twin structure. Nematic epoxy-terminated monomers based on a phenyl benzoate twin mesogen connected by an alkylene spacer were synthesized for these studies. In addition, an epoxy-terminated monomer based on a 1,4-b…
The adsorption of CO on Pd/Al2O3/Ta(110) model catalysts was studied using infrared reflection adsorption spectroscopy (IRAS) for two different Pd coverages, corresponding to 25–30 and 60–70 Å average particle sizes. Striking similarities between the IRAS data for the larger particles and Pd single crystals indicate t…
Manganese-activated ZnGa2O4, prepared at a sintering temperature of 1375 °C with 0.1% MnO dopant, emitted red and green light with peaks at 666 and 508 nm when excited with a laser source (325 nm). The luminescence centers of red emission were ascribed to Mn4+ ions in the octahedral (B) sites of spinel-structure zinc…
A calcium hexaluminate (CaAl 12 O 19 , magnetoplumbite structure) sol was used to coat alumina and yttrium‐aluminum‐garnet (YAG) single‐crystal fibers and single‐crystal alumina plates. When the coated substrates were either annealed or hot‐pressed in polycrystalline alumina and YAG matrices, the calcium hexaluminate…