Showing papers in "Materials Chemistry and Physics in 1992"

TL;DR: In this article, the semiconductive properties of titania are determined by the density of point defects in the crystalline structure, and the synthesis method (sol-gel) provides pure and reproducible solids.

TL;DR: In this article, the fabrication, structures, and properties of epitaxial NiSi2 and CoSi2 thin films were examined, with special attention paid to the atomic structures and the Schottky barrier heights observed from epitaxia silicide/Si interfaces.

TL;DR: In this article, the methods of preparation of carbon-mineral adsorbents produced on the basis of typical sorbents (e.g., silica gels, alumina, titanum oxide, Celite 545) are described.

TL;DR: In this paper, the microstructure and phase transformations in the obtained solids are compared and differences have been observed in particle size and agglomeration state as well as on the crystallinity of just-prepared powders and its evolution under thermal treatment.

TL;DR: In this paper, the point defect self-energies, elastic constants, various shear fault energies and cleavage energies are determined from first-principles for the L 1 2 (Ni 3 Al and trialuminides), B 2 (FeAl and NiAl) and L 1 0 (TiAl) structure-base intermetallics.

TL;DR: The sensitivity of Eu(II) luminescence to changes in electrolyte concentration has been studied in this paper, where the sensitivity of the half-life of the Eu-II luminecence was investigated.

TL;DR: In this article, the charge transfer transitions (including 4f-5d transitions) and the vibronic transitions are dealt with in the context of rare earth spectroscopy, and their interaction with the second coordination sphere is demonstrated.

TL;DR: In this article, a coprecipitation procedure for the preparation of high area CoAl2O4 spinels is described, which involves the precipitation of a crystalline precursor, that has been characterized by XRD, IR and TG-DTA analyses to be a layered mixed hydroxy-carbonate having a structure related to that of the mineral hydrotalcite.

TL;DR: The use of rare earth containing phosphors in a.c. operated thin film electroluminescent (ACTFEL) displays is reviewed in this article, where the authors show that the green material ZnS:Tb3+ has been developed to a level sufficient for technical applications and the blue and red phosphors still need improvements in brightness and stability before they can be applied in TFEL devices.

TL;DR: In this paper, a combination of the 16O(α, α)16O oxygen resonance technique and the transmission electron microscopy (TEM) was used to study the kinetics of nucleation and growth of the Cu2O phase in the CuO matrix.

TL;DR: In this paper, electrodeposited Ni-Fe coatings in 40 wt.% KOH at 80 °C were investigated with respect to the oxygen evolution reaction (OER).

TL;DR: In this paper, the luminescence of the rare-earth ions Eu 3+, Tb 3+ and Ce 3+ in Ca 3 (BO 3 ) 2 is reported.

TL;DR: In this paper, the change in structure of zeolite ZSM-5 catalyst when coke occupies the channel was studied using X-ray diffraction (XRD) methods.

TL;DR: In this article, the fluorescence properties of Ce 3+ ions in YAlO 3 crystals have been studied in the VUV, UV and visible spectral ranges in terms of fluorescence emission and excitation spectra.

TL;DR: In this paper, the hydrogen absorption and desorption behaviors of the Sm2Fe17 compound were studied and the occurrence of the HDDR (Hydrogenation Disproportionation Desorption Recombination) process in the processing of Sm 2Fe17Nx powders with high coercivity was described.

TL;DR: In this article, the Fe(III) complexes formed in the silica network and deposited on the solid surface were analyzed in order to study the structure rearrangement of the network.

TL;DR: In this article, the photoelectrochemical (PEC) solar cell properties of chemically deposited cadmium selenide thin films with heteropolyacids have been studied.

TL;DR: The surface basicity plays an important role in the reaction mechanism, activating and breaking the methane C-H bonds, and creating the CH 3 radicals responsible for the coupling reaction as discussed by the authors.

TL;DR: In this paper, the properties of hepta-and hexa-dentate Schiff bases have been discussed focusing the attention on the magnetic data, and they have been obtained by the reaction of 3-formylsalicylic acid or 2,3-dihydroxybenzaldehyde with the polyamines NH2-(CH2)2-X-NH2 (X = NH, S, CH3-(CH 2)11−) or NH2-R-NH 2 (R = -(CH 2)-NH2)-NH 2 -NH2-

TL;DR: In this article, the authors investigated the effect of mass sorbent on the course of hydrothermal treatment as well as on the homogeneity of obtained materials and showed that a complete capillary condensation of water vapour in the adsorbent pores did not take place.

TL;DR: In this paper, a thermogravimetric analysis was applied to the characterization of the porosity of silica gel and the pore size distributions for different desorption conditions were calculated.

TL;DR: In this article, a powder mixture of ZnCrO4 and CrO3 was calcined in the temperature range 150-1000 °C in air and the structural changes were identified using DTA, XRD and IR analysis.

TL;DR: The devitrification behavior of Li2O · 4GeO2 glass examined by differential thermal analysis and X-ray diffraction is reported and discussed in this paper, where the activation energies of the two stages are found to be 698 and 502 kJ/mol respectively.

TL;DR: In this article, the authors describe the use of various plasma etching techniques in III-V semiconductor technology, which is consistent with an integrated processing concept in that plasma etch is a vacuum technique, and the dry etch reactor chamber can be coupled with other deposition, annealing or epitaxial growth chambers via load locks and transfer arms.

TL;DR: In this article, the luminance excitation spectra of Eu3+ impurities in oxide, fluoride and oxifluoride have been obtained in the 100 to 300 nm range using VUV synchrotron radiation.

TL;DR: In this article, the thermal conductivity of calcium cerate and calcium zirconate was investigated employing the laser flash technique and covering a temperature range from 563 to 1453 K. Variation of the thermal resistivity of these materials as a function of temperature has been examined and the heat transport behaviour discussed.

TL;DR: In this paper, the growth kinetics, electrical and structural properties of microcrystalline silicon formed by direct glow discharge decomposition of heavily hydrogen diluted silane were studied, and it was found that by changing the volume fraction of silane to below 5%, phase transition from amorphous to micro-crystallized silicon occurred.

TL;DR: In this paper, the authors used Rutherford backscattering (RBS), X-ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM) to characterize the chemical and structural properties of the silicon dioxide layer underneath the oxidized Cu 3 Si surface layer.

TL;DR: In this article, the viability of metallorganic chemical vapor deposition process for depositing high quality optical filters at relatively low cost was demonstrated, and MOCVD fabricated, refractive oxide niters consisting essentially of alternating layers of Ta2O5 and SiO2 were found to be suitable for use at high temperatures (> 800 °C) and long operational times (around 3000 h).

TL;DR: In this article, the photophysical properties of complexes of the Eu 3+ and Tb 3+ ions with encapsulating ligands are reviewed, and it is shown that such compounds are species capable of emitting a strong, long-lived luminescence in water solution.