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81.
Reaction of cis-[RuCl2(dppm)2] (dppm = bis(diphenylphosphino)methane) with CS2 and NaOH yields the first ruthenium dithiocarbonate complex, [Ru(kappa2-S2C=O)(dppm)2]. Protonation with tetrafluoroboric acid affords the xanthate complex [Ru(kappa2-S2COH)(dppm)2]BF4 in a reversible manner, suggesting that this may be an intermediate in dithiocarbonate formation. [Ru(kappa2-S2C=O)(dppm)2] reacts with methyl iodide or [Me3O]BF4 to give [Ru(kappa2-S2COMe)(dppm)2]+, also obtained from the reaction of cis-[RuCl2dppm)2] with CS2 and NaOMe. Two modifications of [Ru(kappa2-S(2)C=O)(dppm)2] were examined crystallographically and the structure of [Ru(kappa2-S2COMe)(dppm)2]BF4 and a new modification of cis-[RuCl2(dppm)2] are also reported. 相似文献
82.
Subrata Majumder D. Paramanik V. Solanki I. Mishra D.K. Avasthi D. Kanjilal Shikha Varma 《Applied Surface Science》2012,258(9):4122-4124
Nanodots have been fabricated on rutile TiO2(1 1 0) single crystals using Ar ion beam. Ion beam sputtering creates oxygen vacancies, leading to a 45 nm thick Ti rich layer, on the surface. Post-sputtering, rutile TiO2 also exhibits a decrease in the inter planar separation along [1 1 0] direction. Additionally, blueshift in the Eg Raman mode, representing the vibrations of oxygen atoms along c-axis, is also observed. Both these results suggest the development of a compressive stress along c-axis upon sputtering. Enhancement in intensity of A1g Raman mode also indicates modification in TiO vibrational influence. 相似文献
83.
Minghua Li Xinan Liang Xuewu Xu Sanjeev Solanki Tow Chong Chong 《Journal of Crystal Growth》2010,312(20):3020-3024
Ag doped congruent lithium niobate crystal has been demonstrated as a promising photorefractive material for holographic recording applications. In this paper, the effects of Ag doping on the lattice structure and the optical properties were investigated by XRD, Raman spectroscopy and optical absorption characterization. The Ag ion was proposed to occupy Li-sites and results in lattice deformation. The band gap became narrower and an absorption band at near 500 nm was created with Ag doping. High temperature annealing and UV irradiation were performed to further understand the Ag doping effects. 相似文献
84.
V. S. Sharma R. B. Solanki P. K. Patel R. B. Patel 《Molecular Crystals and Liquid Crystals》2016,625(1):137-145
Two ester homologous series of mesogens, viz., Methyl-p-(p′-n-alkoxy benzoyloxy) cinnamates (X) and Methyl-p-(p′-n-alkoxy cinnamoyloxy) cinnamates (Y) being structurally similar are discussed. Both (X) and (Y) differ in respect of central bridges linking two phenyl rings. Only enantiotropic nematogenic character is observed without exhibition of any smectic character by all members of series (X) and (Y). Thermal stability of series (X) is relatively low as compared to (Y), but nematogenic mesophase lengths are of reverse order. Solid-nematic/solid-isotropic and nematic-isotropic transition curves in the phase diagrams behave in normal manner. 相似文献
85.
We report on the studies relating to fabrication of gelatin B (GB) and zinc oxide (ZnO) based nanocomposite (GB‐ZnO) film deposited on indium‐tin‐oxide (ITO) glass plate, and used for the immobilization of ascorbate oxidase (AsOx) which was further used for ascorbic acid (AA) detection. The structural and morphological studies of GB‐ZnO, and AsOx/GB‐ZnO/ITO bioelectrodes were carried out using XRD, SEM and FTIR techniques. This bioelectrode showed a broad range of linearity (5–500 mg/dL), low detection limit (1 mg/dL), higher sensitivity (0.106 µA mg/dLcm?2) and low value of the apparent Michaelis? Menten constant (Kmapp=0.35 mg/dL) for AA. Efforts are being made to utilize this electrode for sensing AA in real samples in a bid to develop a strip based sensor. 相似文献
86.
K.N. Solanki M.F. Horstemeyer W.G. Steele Y. Hammi J.B. Jordon 《International Journal of Solids and Structures》2010,47(2):186-203
In this paper, we illustrate a formal calibration, validation, and verification process that includes uncertainty in an internal state variable plasticity-damage model that is implemented in a finite element code. The physically motivated continuum model characterizes damage evolution by incorporating material uncertainty due to microstructural spatial clustering. The uncertainty analysis is performed by introducing material variation through model validation and verification. The effect of variability in microstructural clustering and boundary conditions on the sensitivities and uncertainty of the plasticity-damage evolution for the 7075 aluminum alloy is characterized. The results show the potential of this methodology in the evaluation of material response uncertainty due to microstructure spatial clustering and its effect on damage evolution. For damage evolution, we have shown that the initial isotropic damage evolved into an anisotropic form as the deformation increased which is consistent with experimentally observed behavior for 7075 aluminum alloy in literature. Also, the sensitivities were found to be consistent with the physics of damage progression for this particular type of material. Through the sensitivity analysis, the initial defect size and number density of cracked particles are important at the beginning of deformation. As damage evolves, more voids are nucleated and grow and the sensitivity analysis illustrates this as well. Then, voids combine with each other and coalescence becomes the main driver, which is also confirmed by the sensitivity analysis. This work also shows that the microstructurally based damage evolution equations provide an accurate representation of the damage progression due to large intermetallic particles. Finally, we illustrate that the initial variation in the microstructure clustering can lead to about ±7.0%, ±8.1%, and ±9.75% variation in the elongation to failure strain for torsion, tensile, and compressive loading, respectively. 相似文献
87.
We present calculations of the extremal areas of Fermi surface orbits in the bcc transition metal tantalum usingab initio linear muffin tin orbital method in the atomic sphere approximation. The calculations demonstrate the need to include relativistic
corrections for a good representation of the Fermi surface. Self-consistent calculations are performed using various exchange-correlation
potentials. The calculations indicate that Barth-Hedin-Janak exchange provides the best agreement with the experiment. Enhancement
factors are also calculated using the BHJ exchange-correlation potential. These are compared with experimental results as
well as with some of the available theoretical calculations. 相似文献
88.
89.
A chitosan (CS)‐tin oxide (SnO2) nanobiocomposite film has been deposited onto an indium‐tin‐oxide glass plate to immobilize cholesterol oxidase (ChOx) for cholesterol detection. The value of the Michaelis–Menten constant (Km) obtained as 3.8 mM for ChOx/CS‐SnO2/ITO is lower (8 mM) than that of a ChOx/CS/ITO bioelectrode revealing enhancement in affinity and/or activity of ChOx towards cholesterol and also revealing strong binding of ChOx onto CS‐SnO2/ITO electrode. This ChOx/CS‐SnO2/ITO cholesterol sensor retains 95% of enzyme activity after 4–6 weeks at 4 °C with response time of 5 s, sensitivity of 34.7 μA/mg dL?1 cm2 and detection limit of 5 mg/dL. 相似文献
90.