Materials Literature
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Transport and Raman data are presented for samples of Ti 1+x S 2 with carrier densities, determined from the Hall coefficient, ranging from approximately 10 20 cm -3 to approximately 3*10 21 cm -3 . No dependence on carrier concentration, n, is observed for the frequency of the A 1g Raman-active phonon, whereas a stro…
Phase transition in squaric acid is discussed on the basis of pseudo-spin model for the hydrogen bond system. A strong coupling between the lattice distortion and proton system is introduced in order to account for the twin structure and improper ferroelastic behaviour in the low temperature phase. Anomalous elastic c…
The oxidation-reduction properties of mixed oxides in the system Sm-U-O and the variation of their lattice parameters due to oxidation and reduction were examined by means of thermogravimetry and X-ray diffraction. For mixed oxides SmyU1-yO2±x prepared in air, the O/M ratio decreased linearly from 2.667 at y= 0 to nea…
Abstract The amination of chloromethylated polystyrene (CMPS) and benzyl chloride (BC) with amino alcohols was investigated kinetically in dioxane, N,N-dimethylformamide (DMF), and dimethyl sulfoxide (DMSO). The amination rate was related mainly to the branching structure and partly to the pK of amino alcohols; ΔG\ewe…
In the vicinity of Burning Mountain, New South Wales, an unusually thick sequence of kaolinite clayrocks (flint clays) has been considerably altered by heat from the natural combustion of coal seams. Recent quarrying operations in the area have exposed excellent sections through the metamorphosed succession and it is…
We present a theory of dispersive drift transport in amorphous photoconductors. Expressions for the transient current i (t) are derived from the two-site effective medium approximation (EMA) which is equivalent to a generalized master equation approach. The occurrence of Gaussian or dispersive transport is shown to de…
The low-lying plateau response of the pure E (TO) Raman spectra in KH2PO4 (KDP) have been well explained by a simple coupled oscillator model, where the low-lying two TO phonon modes are coupled with highly damped O-H ⃛O motions of the hydrogen bonds. The low-lying pure B2 (LO) spectra have under-damped phonon peaks a…
Abstract Two elastomer layers, differing either in initial degree of crosslinking or in chemical reactivity, were bonded together by a free‐radical crosslinking process. The elastomers employed were polybutadiene (BR) and an ethylene‐propylene copolymer (EPR) differing in the efficiency of crosslinking by dicumyl pero…
Abstract Binary blends of poly(vinyl chloride) and a poly(ether urethane) containing 20 and 40 weight percent, respectively, of poly(vinyl chloride) have been prepared by solution blending from tetrahydrofuran and their degree of mixing investigated using dynamic mechanical analysis. In the polyurethane, transitions w…
Abstract Gerstleyite is monoclinic, a=9.911(8), b=23.05(2), c=7.097(8) Å, β=127.85(7) °, space group Cm, and Z=2. All Sb atoms have essentially 3-fold coordination, forming trigonal SbS3 pyramids. The SbS3 pyramids share corners to form a complex chain parallel to [100]. Na–S bonds cross-link the chains into a slab st…
Kaliumhydroxid reagiert mit Difluorsilanen des Typs R-SiF2-R′ (1-4: R - R′ = CMe3, NC2H5(SiMe3), N-i(C3H7(SiMe3); R = CMe3, R′ = C6H5) unter Bildung der Fluorsilanole R-FSiOH-R′ (7–10). Aus [Me3Si)2N]2SiF2 (6) und KOH entsteht unter zusätzlicher 1,3-Silylgruppenwanderung das Siloxan 16. 7–10 reagieren mit Butyllithium…
Abstract Random copolymerization of aspartic acid with lactic acid and with glycolic acid was carried out using o ‐phosphoric acid as catalyst.
Electrostrictive effects in the potassium tantalate niobate solid solution (K(Ta0.55Nb0.45)O3) have been investigated. The electrostrictive coefficients were determined by a strain gauge technique and by the measurement of hydrostatic pressure dependence of dielectric constant near the Curie temperature. The Q values…
The properties of glow discharge µc Si have been investigated by conductivity, Hall effect and field effect measurements as a function of crystallite size and phosphorus doping ratio. It is concluded that the large increase in σ over a-Si is almost entirely caused by an increased carrier density resulting from delocal…
The efficiency of channel electron multipliers (CEM) falls drastically at energies of the incident electrons greater than a few KeV. For conversion Electron Mössbauer Spectroscopy (CEMS) the conversion electron energies are far greater than a few KeV, and the CEM efficiency at 7 KeV, for example, is about 10% determin…
Earlier studies1-3 have shown that in Pb(Sc1/2Ta1/2)O3 PST and Pb(Sc1/2Nb1/2)O3 which are simple cubic perovskites, the degree of ordering of the different B site cations in the ABO3 structure can be controlled thermally. Quenched disordered crystals and ceramics show diffuse dispersive dielectric properties, while we…
Samples of C62500 aluminum bronze were treated by a continuous wave CO2laser to rapidly melt and quench the surface. This processing transformed the surface layer from multiphase\beta' + \gamma_{2} +primary and secondary iron-rich δ to homogeneous, supersaturated single-phase\beta'solid solution. The cavitation erosio…
Abstract The interfacial reaction of NiO and α‐Al 2 O 3 to NiAl 2 O 4 is investigated by means of Rutherford backscattering spectrometry (RBS) using 2.95 MeV He + ions. The NiO is obtained by oxidation at 800°C of a nickel film vapour deposited on to alumina substrates. The reaction of NiO and Al 2 O 3 does not procee…
Successive ferroelectric phase transitions were discovered in CsLiMoO4, CsLiWO4 and RbLiMoO4 single crystals. Strong elastic and no dielectric anomalies were found with temperature lowering in the initial cubic phases. The phase transitions are qualitatively described as pseudoproper ferroelectric ones.
The effects of co-existing atomic and magnetic clustering on electrical resistivity are considered. It is shown that in Cu-Ni alloys such clustering produces competing effects and that while atomic clustering dominates the behaviour in alloys containing more than about 25% Ni, the magnetic clustering effects are predo…