Materials Literature
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Semiconductor detectors based on natural diamonds have been installed on the Large Helical Device (LHD) heliotron to measure the energy distribution of charge exchange fast neutral particles from different viewing angles. Advantages of a natural diamond detector (NDD) are (1) very compact size, (2) relatively easy han…
Cyclotetramerization of a mixture of 3,4-dicyano-1,2,5-thiadiazole or 3,4-dicyano-1,2,5-selenodiazole with 3,6-diamyloxyphthalodinitrile gives new unsymmetrical porphyrazines with annulated 1,2,5-thia(seleno)diazole and 3,6-diamyloxybenzene rings; the structures of the 1:3 products H2{XN2}{3,6-(OAm)2Bz}3Pz (X = S, Se)…
The solid state system Bi2O3:ZrO2 has been investigated up to 28 mol% ZrO2 using X-ray and neutron powder diffraction, ac impedance spectroscopy and differential thermal analysis. X-Ray powder diffraction has shown that a solid solution is formed with general composition Bi2 − xZrxO3 + x/2 (0.05 ≤ x ≤ 0.17) for sample…
The gold(I) precursor Au(O2CNEt2)(PPh3) has been successfully employed to graft isolated Au(PPh3) fragments on amorphous silica. Molecular models of the silica surface, i.e. Ph3SiOH, (c-C5H9)7Si7O12SiOH and (c-C5H9)7Si7O9(OH)3, have been found to react with Au(O2CNR2)(PPh3), R = Me, Et, yielding the corresponding sila…
The effects of chain cleavage and circular permutation on the structure, stability, and activity of dihydrofolate reductase (DHFR) from Escherichia coli were investigated by various spectroscopic and biochemical methods. Cleavage of the backbone after position 86 resulted in two fragments, (1--86) and (87--159) each o…
Results obtained for polyacrylonitrile microcellular foam thin films deposited on carbon fibers are presented. It appears that surface modifications by flow or water steam at high temperature lead to an increase of the film surface area as well as a proportional increase of capacitance. The films were characterized by…
Salts of the Me3N+-TEMPO cation radical (Me3N+-TEMPO = N,N,N-trimethyl(1-oxyl-2,2,6,6-tetramethylpiperidin-4-yl)ammonium) with I− and PF6− are prepared. Their crystal structure and magnetic properties are reported (antiferromagnetically coupled dimers for (Me3N-TEMPO)I and antiferromagnetically coupled chains for (Me3…
Dimethyl sulfoxide reductase is a heterotrimeric enzyme (DmsABC) localized to the cytoplasmic surface of the inner membrane. Targeting of the DmsA and DmsB catalytic subunits to the membrane requires the membrane targeting and translocation (Mtt) system. The DmsAB dimer is a member of a family of extrinsic, cytoplasmi…
This study introduces a novel approach for producing powder through an electrochemical route. To this end, nanocrystalline powder was coprecipitated electrochemically by the cathodic electrogeneration of hydroxyl ion from an aqueous ammonium nitrate electrolyte. The powder was deposited potentiostatically in a quiesce…
Current transport through mesa structures formed by Pt electroless deposition on p-Si wafers has been studied. The silicon treatment in the solution of sodium chloroplatinate in dilute HF acid is shown to result in both Pt nucleation on the Si surface (cathodic process) and Si wafer etching by fluoride ions (anodic pr…
We provide an overview of theoretical models of plastic deformation processes in nanocrystalline materials. The special attention is paid to the abnormal Hall-Petch relationship which manifests itself as the softening of nanocrystalline materials with reducing the mean grain size. Theoretical models are considered whi…
A catalytic system consisting of water-soluble metal sulfophthalocyanines (MPcS) or various ruthenium complexes and mono-persulfate as the oxidant was effective in the oxidation of cyclohexanone, cyclohexanol and cyclohexane to adipic acid with different yields and selectivity. Oxidations were conducted at room temper…
CydR is an Fnr-like protein in the obligatory aerobic nitrogen-fixing bacterium Azotobacter vinelandii. The cydR mutant overproduces the cytochrome bd terminal oxidase. Using two-dimensional polyacrylamide gel electrophoresis, we showed that beta-ketothiolase and acetoacetyl-CoA reductase were also overexpressed in th…
At Steep Cone hot spring, Lower Geyser Basin, Yellowstone National Park, a mound of siliceous deposits called "siliceous sinter" forms from discharged boiling geothermal water that is supersaturated with amorphous silica. Electron-probe microanalyzer (EPMA) observations suggested that silica is deposited on the surfac…
Improvement of the paint adhesion to a polypropylene (PP) bumper has been investigated without using a primer by treating the bumper surface with O2, H2O, and acetylene plasmas. All the plasma treatments resulted in an increase of the adhesion strength in dry conditions. The adhesion strength could be increased up to…
To develop a new technique for the effective utilization of bagasse, cyanoethylation was attempted to see if bagasse could be converted into a thermoplastic material. The effects of various reaction parameters (temperature, time, alkali concentration, and acrylonitrile-to-bagasse ratio) on the extent of the cyanoethyl…
A highly selective and stable FeCl2/SiO2 catalyst system was studied for the dehydrochlorination of various chloro-organic compounds from the fuel oil derived from polyvinyl chloride (PVC) containing waste plastics.
Nifedipine is a poorly water soluble drug that demonstrates low bioavailability. In a previous study, a coground mixture of nifedipine with sodium deoxycholate (DCNa), a bile salt, immediately produced colloidal particles when dispersed in water. In this study, the effect of the weight fraction of DCNa, grinding time,…
Large power transformers belong to a class of vital and very expensive components in electric power systems. Accordingly, high demands are imposed on power transformer protective relays. The operating conditions of transformer protection, however, do not make the relaying task easy. Protection of large power transform…
Synthetic organic chemistry normally achieves selectivity by manipulation of the intrinsic reactivity of the substrate, but enzyme use is quite a different principle. The geometry of the enzyme-substrate complex determines enzymatic selectivity, completely overwhelming any normal selective reactivities. Biomimetic che…