Showing papers in "Materials Letters in 1998"

TL;DR: The electrical and gas sensing properties of chemically deposited zinc oxide (ZnO) films were investigated in this paper, where two activation energy values, 0.3 eV and 0.8 eV, were determined in the temperature range 300-400 K which are attributed to oxygen vacancy (VO) donor and heat of chemisorption of the O2− species.

TL;DR: In this paper, 13 different configurations of a new class of piezoelectric devices called THUNDER (thin layer composite unimorph ferroelectric driver and sensor) were tested at two stages of the manufacturing process: before and after repoling.

TL;DR: In this article, the dc magnetron reactive sputtering of cadmium in an oxygen and argon atmosphere has been studied for their structural, electrical and optical properties, showing resistivity of 4.6×10−3 Ω cm, Hall mobility of 53 cm2/V s, carrier concentration of 3.5×1019 cm−3, with an optical transmission of 85% in the wavelength range 600-1600 nm and with a band gap of 2.46 eV.

TL;DR: In this paper, pure γ-Fe2O3 particles were prepared by a continuous process from cw CO2 laser induced pyrolysis of a 30% solution of iron pentacarbonyl in isopropanol with a yield of about 50% and an average productivity of 0.05 g/h.

TL;DR: In this paper, the effect of ultrasonic treatment on the as-cast alloy microstructure can be summarized as follows: reduction of mean grain size, variation of phase distribution and better material homogeneity and segregation control.

TL;DR: In this paper, high surface area SnO 2 sensor materials were systematically synthesized by a surfactant incorporating method, and the results showed that a linear relationship exists between sensor surface area and its sensitivity to H 2.

TL;DR: In this article, it has been proposed that during the dehydroxylation and decomposition of the magnesium diethoxide gel, some vacancies are generated and nanocrystalline MgO is formed from the break down of the brucite crystalline structure.

TL;DR: In this article, a nanoscale MgO powder was synthesized from magnesite ore by a wet chemical method using acid dissolution to obtain a solution from which magnesium containing complexes were precipitated by either oxalic acid or ammonium hydroxide, the transformation of precipitates to the oxide was monitored by thermal analysis and XRD and the transformed powders were studied by electron microscopy.

TL;DR: In this article, the fracture toughness of two thermally sprayed tungsten carbide/cobalt-chromium coatings of nominally identically composition, one produced by the Detonation Gun (D-Gun) process and one by the High Velocity Oxy-fuel (HVOF) process, has been determined by the indentation method.

TL;DR: Rietveld structure refinement was conducted on X-ray powder diffraction data of TiCN and the existing structural model for TiCN, based on a cubic lattice with random occupation of sites by Ti, C and N, was found to be incorrect.

TL;DR: In this paper, single crystal samples of lithium niobate have been spatially patterned with photoresist, and subsequently domain inverted using electric field poling, to produce a range of two dimensional spatial domain structures.

TL;DR: In this paper, a monophasic potassium niobate KNbO3 was synthesized via a hydrothermal process, where KOH with a concentration of 8 M was reacted with Nb2O5 particles at 200°C.

TL;DR: In this article, the percolation threshold of high-density polyethylene (HDPE)/isotactic polypropylene (iPP) blends filled with vapor-grown carbon fiber (VGCF), 1.25 parts per hundred parts resin (phr) content, is much lower than those of the individual polymers.

TL;DR: In this article, the synthesis of nanoparticulate MoS2 and WS2 is described, where the synthesis is performed by the reaction of the hexacarbonyls with H2S in a microwave plasma.

TL;DR: In this article, an attempt to improve the shape memory characteristics by precipitation-hardening was made for non-equiatomic TiPd-Ni high temperature shape memory alloys (Ti:(Ni, Pd) ≠ 50:50) by differential scanning calorimetry, high temperature tensile tests and transmission electron microscopy.

TL;DR: In this paper, the inhibitory effect of mixed alumina and silica additives with molar ratios of [Al]/[Ti]=0.05 and [Si]/ [Ti]= 0.05 on the phase transformation of anatase to rutile was investigated.

TL;DR: In this paper, the influence of natural ageing on the overall subsequent precipitation processes of two Al-Mg-Si alloys has been studied by a series of differential scanning calorimeter (DSC) analyses.

TL;DR: In this paper, high pure submicron alumina powder compacts were sintered to a near theoretical density of 99.7% by 2.45 GHz microwave processing.

TL;DR: In this article, the preparation of ZnO microcrystallites using a microemulsion method and their electron spin resonance (ESR) properties are reported for the first time.

TL;DR: In this article, the influence of boron on martensitic transformation temperatures, microstructure and high-temperature mechanical properties of shape memory alloys has been studied.

TL;DR: In this article, a solvent thermal process was developed for preparation of ultrafine powder of bismuth sulfide in ethanol at 140°C through a thermal reaction between Bismuth bichloride and thiourea.

TL;DR: In this article, a single crystal of a new organic nonlinear optical material, urea-(d)tartaric acid (UDT) is reported, which is orthorhombic and belongs to the D 2 point group.

TL;DR: In this paper, the authors showed that the reversible structural phase transformation is due to the change of orientation of intercalated acetates depending on the type of ligation, chelating or unidentate ones.

TL;DR: In this paper, the possibility of electrophoretic seeding of diamond particles via the cathodic process has been demonstrated and the possible mechanisms of particle charging were discussed, and the results were characterized by SEM.

TL;DR: In this article, the authors performed cathodic electrosynthesis of TiO 2, RuO 2 and composite RuO2 -TiO 2 films on Pt substrates via hydrolysis of TiCl 4 and RuO 3 · n H 2 O salts dissolved in water or mixed methyl alcohol-water solvent.

TL;DR: In this paper, the authors synthesize mullite fibers from an aqueous solution of aluminum isopropoxide, aluminum nitrate and tetraethylorthosilicate by the sol-gel method.

TL;DR: Carbon and high alloy steels were boronized and tested in molten aluminium and zinc baths at 630°C and 500°C, respectively, and the boride layers were found to be extremely resistant to both Al and Zn molten metals.

TL;DR: In this article, a poly(acrylic acid)-metal nanocomposites were synthesized by irradiating the solutions of metal ions (Ag+, Cu2+, Ni2+) in acrylic acid monomer with γ-ray.

TL;DR: The aerogels are translucent yellow in appearance, are amorphous to X-rays, and have a surface area of 350 m 2 /g as mentioned in this paper, and the empirical formula of the material is TiO 3 H 2.7 C 0.35.

TL;DR: The incorporation of Ni metal into PolyHIPE (a generic hollow fibre polymer produced by emulsion polymerisation) was attempted by both electroless deposition and electrodeposition and the resulting composites were characterised by a Scanning Electron Microscope (SEM) and Energy Dispersive Analysis by X-ray (EDAX) analysis.