Materials Literature
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Cu(I)L complexes catalyze the Ullmann reaction2-BrC6H4CO2− + H2O → 2-HOC6H4CO2− + Br− + H+however the process is slow and undesirable yields of benzoic acid and diphenoic acid are formed. The optimal ligand, L, for this catalyst should enhance the rate of the process, probably via shifting the redox potential of the C…
Essential oils of citrus fruits have many uses in consumer products so that efficient methods for their isolation are needed. Membranes are often used in the separation process but a common problem is that the flux through the membranes decreases with time. In the present study we examined whether ceramic membranes mi…
α(6H)-SiC powders mixed with 11 types of metal boride, B and C were sintered at high temperatures (1800-2200°C for 30min). MoB, NbB2, TaB2, TiB2, VB2, WB, and ZrB2 promoted the densification of SiC powder and sintered SiC had a high fracture toughness (4.07-4.75MPa·m1/2). The addition of metal boride enabled us to con…
We report the relaxation of ultraviolet-radiation-induced structure and long-lasting phosphorescence in Sn2þ—Cu2þ co-doped glass with composition of 70SiO2.20Na2O·10CaO·0.05CuO·0.05SnO in mol ration. After irradiation by an ultraviolet lamp λmax ¼ 254 nmÞ with a power density if 5 mW/cm2 for 30 min, a visible light pe…
The carbohydrate fraction of a hot spring sulfur-turf bacterial mat was shown to contain cellulose by the examination of neutral sugar composition, methylation analysis, and the identification of free oligosacchrides obtained from an acetolyzate of the desulfurized sulfur-turf mat. This suggested that the sulfur-oxidi…
The crystal structures and magnetic properties of three compounds within the system BaIrxFe1−xO3−δ have been investigated using a combination of X-ray and neutron powder diffraction, high resolution transmission electron microscopy and d.c. SQUID magnetometry. BaIr0.2Fe0.8O2.932(5) and BaIr0.6Fe0.4O3 adopt the 6H stru…
Correlations between in situ Raman spectroscopic and catalytic measurements on palladium based three-way catalysts during the reduction of NO by CO have been tentatively established. Particular attention to the selectivity towards the transformation of NO into N2O has been paid in order to explain why N2O is the main…
The etch rates of anodic oxides in dilute fluoride solutions have been determined by using a new approach to the analysis of anodic current oscillations. The variation of the thickness of the anodic oxide with time has been measured by in situ Fourier transform infrared spectroscopy. The change in oxide thickness can…
Weakly agglomerated nanocrystalline (ZrO2)0.92(Y2O3)0.08 − x(Sc2O3)x (x = 0–0.08) powders (8.4–9.9 nm in size) in a cubic structure with high surface area (145–153 m2 g−1) were synthesized by a two-step hydrothermal process in the presence of urea: a stock solution of metal nitrates and urea was heated at 80 °C for 24…
This work was carried out to prevent the rolled-in defects originated from the roll surface deterioration through the investigation of the effect of the thermal fatigue property of hot strip mill work roll materials on the roll surface deterioration and subsequent surface defects in the cold-rolled ultra-low carbon st…
Phase formation processes at T = 350–1000°C in Lu(Gd)-Ti-O samples obtained by co-precipitation method are studied. Thermal processing of freeze dried co-precipitation products results in formation of Lu2Ti2O7 with fluorite structure at 650°C. The phase transition of fluorite to pyrochlore occurs at 750–800°C. At T >…
Gallium sulfide glasses were prepared in the RS-Ga2S3 (R=Ca, Sr, Ba) systems. Respective glass forming regions are 67.5-70.0 mol% CaS, 63.8-68.8 mol% SrS and 60.0-73.8 mol% BaS. Transmission spectra in the visible region, refractive index and glass transition and onset crystallization temperatures were measured for re…
Acoustic and dielectric properties of deuterated betaine arsenate (DBA), betaine phosphite (BPI) and glycine phosphite (GPI) have been studied in the vicinity of ferroelectric, antiferroelectric and improper ferroelastic phase transitions. The temperature dependences of the velocity and attenuation of acoustic waves a…
The mechanism of leakage current of porous organosilicate glass (POSG) with plasma ashing is investigated. The plasma ashing often deteriorates the POSG film, causing moisture uptake. We find that the leakage-current mechanism of POSG transforms from Schottky emission into ionic conduction after plasma treatment. The…
Several liquid crystalline compounds derived from 2-aminonaphthalene have been synthesized. The molecules are designed to accommodate two napthalene moieties. The molecular structures of these new compounds have been characterized by element analysis, FTIR, and NMR spectral studies. The mesomorphic behavior has been s…
By using the FAST system, a range of lightweight wool and wool-blend fabrics, including three wool fabrics treated with Synthappret BAP shrinkproofing resin to obtain machine-washable properties, was investigated in terms of tailorability. The main problems with these fabrics were found to be their low warp extensibil…
Adsorption of CO on Pd/WO3-ZrO2 sample at 85 K results in formation of carbonyls typical of the support as well as of Pd3+-CO species (2212 cm−1). The latter are masked by the strong Zr4+-CO band. Even at 90 K the Pd3+ sites are reduced to Pd2+ (the respective carbonyls absorbing at 2184 cm−1) and, at higher temperatu…
The composition-property relationships of LDPE-PP binary blends have been investigated. Young's modulus, yield strength and flexural strength of the blends varied monotonically with composition, whereas the elongation at failure and the true ultimate tensile strength for the blends with 30-50 wt-% PP exhibited synerge…
Polycrystalline ceramics of SmBi 3 Ti 3 O 12 were prepared by the solid state reaction method. Extensive impedance studies were carried out on these samples. From the measurements, it was observed, that low concentrations of a rare earth substituent for the bismuth site showed broad dielectric and impedance peaks. Fer…
Recent applications of infrared and Raman spectroscopy in the study of the metamict (or "amorphized") state, high-temperature recrystallization and radiation-induced OH species in natural zircon (ZrSiO4) and titanite (CaTiSiO5) are reviewed.