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31.
Saha R Biswas S Steele IM Dey K Mostafa G 《Dalton transactions (Cambridge, England : 2003)》2011,40(13):3166-3175
The metal complexes, [M(Hdammthiol)(2)]Cl·3H(2)O [M = Cr(III) (1), Fe(III) (2)] [where H(2)dammthiol is the thiol form of the ligand, diacetylmonoxime morpholine N-thiohydrazone] were synthesized by metal template reactions of diacetylemonoxime with morpholine N-thiohydrazide in the presence of CrCl(3)·6H(2)O and FeCl(3)·6H(2)O. Both the complexes (1 and 2) were characterized by single crystal X-ray crystallography, spectroscopic (IR and UV-vis), M?ssbauer and TGA analyses. The single crystal X-ray studies of both complexes show that the supramolecular hosts, constructed by the discrete mononuclear complexes, form supramolecular channels along the c-axis which are filled up by water-chloride clusters. In both complexes, the 1D water-chloride chain with chair-like architecture within the supramolecular hosts presents novelty. The magnetic measurement study of Fe(III) complex shows a spin crossover from S = 1/2 at 2.5 K to S = 5/2 at 300 K. At very low temperature, the presence of strong cooperative hydrogen bonding interactions stabilizes the S = 1/2 state. 相似文献
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J.R. Owen W.C. Maskell B.C.H. Steele T.Steen Nielsen O.Toft Sørensen 《Solid State Ionics》1984,13(4):329-334
LiAl thin film electrodes were formed by cathodic conversion of the surface of a 50 micron Al foil in a propylene carbonate based electrolyte. The films were cycled both in Li-doped poly(ethylene oxide) and propylene carbonate. On charging, an overpotential of 40 mV was required to sustain growth of the LiAl phase, but the diffusional overpotential was minimal. A simple diffusional model for the discharge predicted serious rate limitation due to slow diffusion in the α phase. However, measurements of the diffusion coefficient gave values many orders higher than previously reported and even greater values were required to explain the discharge rates. Cycling behaviour showed that the electrode degradation was less severe in the polymeric electrolyte than in propylene carbonate. 相似文献
35.
A new spectrophotometric method for the determination of very small amounts of xanthate in solutions, particularly cyanide solutions from gold-extraction plants, is described. It is based on the formation and extraction of copper(II) xanthate. The coefficient of variation is 1.0% at the 40-ppm level and 3.4% at the 4-ppm level and the lower limit of determination is approximately 0.5 ppm. Copper(II) xanthate normally decomposes into copper(I) xanthate and dixanthogen, but in the proposed method the decomposition is delayed. 相似文献
36.
G.M. Crawley W.F. Steele J.N. Bishop P.A. Smith S. Maripuu 《Physics letters. [Part B]》1976,64(2):143-146
The mass and some energy levels of the nuclide 44Ar have been determined from the 48Ca(3He, 7Be)44Ar reaction. A comparison with theoretical values of the mass is made. 相似文献
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There are many points of uncertainty in the subject of cochlear models. In this paper only the question of efficient computing methods is addressed. For the cochlear model with a one-dimensional approximation for the fluid motion, Zweig, Lipes, and Pierce [J. Acoust. Soc. Am. 59, 975-982 (1976)] have shown that the WKB method agrees well with a direct numerical integration. For the two-dimensional fluid model, Neely [E.D. thesis, California Institute of Technology, Pasadena, CA (1977)] has shown that a direct finite difference solution is an order of magnitude faster than the integral equation approach used by Allen [J. Acoust. Soc. Am 61, 110-119 (1977)]. In the present work, a formal WKB solution is derived following Whitham [Linear and Nonlinear Waves (Wiley, New York, 1974)]. The advantage of this formulation is simplicity, but the disadvantage is that no error estimate is available. We find that the numerical results from the WKB solution agree well with those of Neely (1977), while the computer time is reduced by another order of magnitude. Thus, the WKB method seems to offer the satisfactory accuracy, efficiency, and flexibility for treating the more realistic cochlear models. 相似文献
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Lifetimes of the C3Δ state of TiO have been measured for vibrational levels v′ = 0 to 2 from the decay of photoluminescence excited in a chemiluminescent flame by a short-pulsed (5 nsec) tunable dye laser. Radiative lifetimes of τv′=0 = 37 ± 9 nsec, τv′=1 = 29 ± 7 nsec, τv′=2 = 28 ± 7 nsec were obtained and were used to estimate oscillator strengths which were found to be in good agreement with earlier values based on intensity measurements. 相似文献