Materials Literature
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The thermal expansion coefficients of various perovskite-type oxides have been estimated by re-evaluating the parameters used in the Ruffa's method. The Morse potential has been used to evaluate the thermal expansion coefficient assuming the Debye model for the frequency distribution of the Morse oscillator. The param…
Fifteen new steroidal glycosides were obtained from the roots of Metaplexis japonica M. (Asclepiadaceae). These glycosides were confirmed to have ramanone, 12-O-acetylramamone, pergularin, 12-O-acetylpergularin and deacylmetaplexigenin as the aglycone and 2, 6-dideoxyhexopyranoses as the sugar sequence by spectroscopi…
Chemical implantation of palladium(II) has been carried out under mild conditions by reacting trans-Pd(O 2 CNEt 2 ) 2 (NHEt 2 ) 2 with the silanol groups of amorphous silica, carbon dioxide and secondary amine being released in the process. The palladium-containing silica has been characterized and the coordination en…
The impact of nutrient supply ratios on the functional geometry of phytoplankton has been studied by means of competition experiments with phytoplankton communities from the Arabian Sea. Cell length and deviation from spherical shape of dominant competitors increased with Si:N ratios.Surface:volume ratios were minimal…
AbstractElectrochemical potentiodynamic measurements have shown that the critical pitting potential Epit of AISI 316L steel in aqueous solutions decreases linearly with increasing chloride ion concentration in the range 10−3–2·4M NaCl and with increasing temperature from 30 to 70°C. The critical chloride concentration…
Poly(tetrafluoroethylene) (PTFE) films were surface-modified by employing a reaction solution of benzophenone and sodium hydride in anhydrous dimethylformamide at a temperature of 150 degrees C for 12 h. Electron spectroscopy for chemical analysis (ESCA) showed defluorination, oxygen incorporation, and extensive unsat…
${\mathrm{CaGdAlO}}_{4}$ crystals doped with Ti ions were grown using the Czochralski technique in a reducing atmosphere in order to convert the valence of Ti to trivalence. The fluorescence of the ${}^{2}{E}^{2}{T}_{2}$ transition of ${\mathrm{Ti}}^{3+}$ in the crystals shows a broad band with a peak at 535 nm excite…
The syntheses of heterometallic compounds involving praseodymium, barium and copper ions by using 2,2′-thiodiethanol (H2tde) as the bridging ligand have been investigated. Three new polynuclear compounds, Pr2Cu4(tde)3(Htde)2(hfacac)4(µ6-O) 1, Ba2Cu2(Htde)2(hfacac)4 2 and Cu4(tde)2(hfacac)4 3 have been obtained and cha…
Chemical and structural effects in LuAlO3-Ce3+ single crystals grown by the Bridgman method were studied using spectral emission, x-ray, etching and optical techniques. The Ce concentration distribution was found to exhibit the normal freeze behavior with partition coefficient of 0,17. The expansion of the unit cell v…
A novel dimeric butenolide called glochidiolide was isolated from the leaves of Glochidion acuminatum. Its structure was elucidated by X-ray analysis.
Article Dehydration and Rehydration of Vermiculites: IV. Arrangements of Interlayer Components in the 1.43 nm and 1.38 nm Hydrates of Mg-Vermiculite was published on January 1, 1998 in the journal Zeitschrift für Physikalische Chemie (volume 207, issue 1-2).
Encapsulation of pyrrole in two kinds of zeolite Y (NaY and USY) with various concentrations of CuII ions has been attempted by a gas diffusion process, and the products have been characterized by means of thermoanalytic and spectroscopic methods. From the results, it was found that the progress of polymerization depe…
This paper demonstrates the effects of a laminated busbar on power electronics circuits, and compares its characteristics to those of other power distribution topologies. Included in the discussion are physical as well as electrical characteristics, along with the manufacturing implications that need to be considered.
Ground states for alkyl-substituted Schlenk hydrocarbon diradicals 1–4 in frozen 2-MeTHF or THF are determined at low temperatures by EPR spectroscopy (4–80 K) or SQUID magnetometry (2–80 K). Diradicals 1, 2, and 3 are triplet ground states. Diradical 4 is the singlet ground state with the singlet–triplet gap, ΔEST ≈…
Several branched and dendritic aromatic amides have been obtained by reacting tris(4-aminophenyl)methane 3 either with aryl iodide 1 in a Pd-catalysed carbonylation or with carboxylic acids in the presence of the coupling agent triphenyl phosphite. Nonpolar aromatic substituents and solubilising groups at the peripher…
We examine the behaviour of the (310) symmetric tilt boundary with applied shear stress in a face-centred cubic Lennard-Jones crystal. Our purpose is to observe the mechanical properties of grain boundaries resulting from interface melting. The grain boundary is seen to exhibit significant self-diffusion at temperatur…
One flask synthesis of dithienylmethane and difurylmethane is reported. The reaction of aldehydes with excess furan or thiophene affords the meso-phenyldithienylmethane (DTM) and meso-phenyldifurylmethane (DFM), respectively. The reaction is catalyzed with trifluoroacetic acid or with BF3·O(Et)2. An acyl group is sele…
Hydrogen is considered one of the major problems for ferritic and martensitic steel structures in future fusion reactors. In contrast to hydrogen from other sources, hydrogen produced by nuclear transmutations cannot be kept away by barriers but must be drained off through the surfaces. An upper limit of the diffusion…
The microstructure and dielectric properties of A‐site‐excess and stoichiometric‐composition strontium calcium titanate ((Sr,Ca)TiO 3 ) ceramics were investigated in the present study. Ruddlesden‐Popper‐type planar faults in A‐site‐excess specimens were observed using high‐resolution scanning transmission electron mic…
Morphology changes induced in polycrystalline silver catalysts as a result of heating in either oxygen, water or oxygen–methanol atmospheres have been investigated by environmental scanning electron microscopy (ESEM), FT-Raman spectroscopy and temperature programmed desorption (TPD). The silver catalyst of interest co…