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81.
82.
Jun‐Feng Wu Dong‐Mei Li Li‐Feng Cui Chang‐Fu Zhuang Sai‐Nan Song Tie‐Gang Wang Ji‐Qing Xu Heng‐Qing Jia Ning‐Hai Hu 《应用有机金属化学》2007,21(12):1033-1040
Mo2O2S2(HGly)(Gly)2 1 and K6[Mo2O2S2(nta)2][Mo2O2S2(ntaH)2]·4H2O 2 were synthesized by the reactions of (NH4)2MoS4 and amino acids L (L = glycine, nitrilotriacetic acid) in ethanol–water medium at ambient temperature. The two complexes were characterized by elemental analysis, infrared spectra, UV–visible spectra, TG–DTA and XPS. X‐ray crystallographic structural analyses revealed that compound 1 is a binuclear Mo? S? glycinate complex, a glycinate ligand is coordinated to each molybdenum atom through its amine nitrogen and carboxylato oxygen, respectively, and the third glycinate acts as a bridge through its two carboxylato oxygens linking the two molybdenum atoms. Compound 2 is also a binuclear Mo? S complex with two nitrilotriacetate ligands, each of which is coordinated to a molybdenum atom via its two β‐carboxylato oxygens and a nitrogen atom. Simultaneously, each molybdenum atom in 1 and 2 is chelated to a terminal oxygen and two bridging sulfurs to complete the octahedral configuration. Their catalytic activities in the reduction from C2H2 to C2H4 as well as other binuclear Mo? S? polycarboxylate complexes, a [Fe4S4] single cubane and a chainlike Mo? Fe? S compound were investigated and it was found that 1 exhibited relatively good catalytic activity. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
83.
A generalized expression for the differntial tunnelling current density based on the problem of electron energy distribution
introduced during the process has been presented. This is directly applicable to junction devices for the evaluation of their
tunnelling I–V characteristics.
A list of symbols appear at the end of the paper. 相似文献
84.
85.
Following the approach of optical reference geometry we derive the expression for the total force in the radial direction acting on a charged particle in magnetic fields superimposed on the static Schwarzschild background and show the possible existence of bound orbits for particles in the field of ultra compact objects at distancesr?3m wherein the Lorentz force counterbalances both the gravitational and centrifugal forces. 相似文献
86.
dc ionic conductivity measurements were made on single crystals of Pb(NO3)2 doped with monovalent Na+ and K+ in the temperature range of 100–400°C. In the extrinsic region the conductivity was found to decrease with Na+ having a smaller ionic size, and to increase with K+ with larger ionic size compared to the host Pb ion. Conductivity is attributed to the mobility of anti-Frenkel defects as in the case of PbF2. Dielectric loss measurements were made on the Pb(NO3)2: K+ system in the frequency range of 300 Hz to 20 kHz at different temperatures. Impurity vacancy pairs of the type K+-(NO-3)V are found to be responsible for the observed dielectric loss peaks. The maximum peak frequency is found to increase with temperature. 相似文献
87.
88.
Factors influencing the in vitro release of bovine serum albumin (BSA) from poly(butylcyanoacrylate) (PBCA) nanocapsules, such as the pH value, BSA loading, the polymeric nanocapsule walls and protein molecular weight, were investigated in detail. The BSA release rate was affected by the degradation rate of the polymeric wall and protein loading. For low molecular weight proteins, the initial burst release was faster than that of high molecular weigh proteins and got to equilibrium quickly. Sodium dodecyl sulfate–polyacrylamide gel electrophoresis results showed that BSA encapsulated within PBCA nanocapsules did not suffer covalent aggregation or fragmentation during the initial days of in vitro incubation. For nanocapsules prepared by interfacial polymerization in water-in-oil microemulsions, these findings were useful as a foundation for the development of nanocapsules with desired properties. 相似文献
89.
N. Katayama M. Kajita H. Koiso Y. Kubota F. Sai S. Sakamoto F. Shimizu T. Tsuboyama S.S. Yamamoto 《Nuclear Physics A》1984,423(3):410-418
We have investigated the dp → ppn non-spectator breakup reaction obtained from the KEK l m liquid hydrogen bubble chamber exposed to a beam of deuterons at ten momenta in the range 2.0–3.7 GeV/c. The pn and pp effective mass distributions in the two momentum regions 2.0–2.9 GeV/c and 3.0–3.7 GeV/c show no structure. 相似文献
90.
Microwave-assisted growth and characterization of water-dispersed CdTe/CdS core-shell nanocrystals with high photoluminescence 总被引:5,自引:0,他引:5
He Y Lu HT Sai LM Lai WY Fan QL Wang LH Huang W 《The journal of physical chemistry. B》2006,110(27):13370-13374
A novel microwave-assisted method of growth of high-quality CdTe/CdS core-shell nanocrystals in the aqueous phase is presented in this paper. The photoluminescence quantum yield (PLQY) is greatly enhanced by epitaxial growth of the CdS shell. Under optimum conditions, the PLQY of as-prepared nanocrystals reaches as high as 75% without any post-treatment. Furthermore, these investigations demonstrate that microwave irradiation is tremendously useful for fast epitaxial growth of nanocrystals due to its special characteristics. As a result, the microwave synthesis is sufficiently time-economizing (only five minutes are required) to obtain optimum amounts of CdTe/CdS core-shell nanocrystals in comparison to the conventional illumination method (several days are required). Therefore, this current research not only provides a rapid microwave synthesis for producing highly fluorescent CdTe/CdS core-shell nanocrystals, but also it presents some advantages of the microwave synthesis in comparison to the illumination method. 相似文献