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81.
82.
Single crystals of the title compound are obtained from a melt of U3O8, MoO3, and excess Cs2CO3 (Pt crucible, 950 °C, 12 h, cooling rate 5 °C/h). 相似文献
83.
A uranylcontaining compound [U(CO3)3(H2O)2]·2H2O has been synthesized under hydrothermal condition and characterized by X-ray single-crystal analysis. Crystal structural analysis indicates that this compound consists of three CO32- molecules, one U6+. The results reveal that the title compound presents a 3D frame work built up by O-H…O week hydrogen bonds interactions. The central uranium atom is eight-coordinated through three CO32- molecules and two H2O. The compound shows a coplanar hexagonal network structure, each hexagon containing a hexagonal hole with a water moleculet. CCDC: 737313. 相似文献
84.
A uranylcontaining compound [U(CO_3)_3(H_2O)_2]·2H_2O has been synthesized under hydrothermal condition and characterized by X-ray single-crystal analysis. Crystal structural analysis indicates that this compound consists of three CO_3~(2-) molecules, one U~(6+). The results reveal that the title compound presents a 3D frame work built up by O-H……O week hydrogen bonds interactions. The central uranium atom is eight-coordinated through three CO_3~(2-) molecules and two H_2O. The compound shows a coplanar hexagonal network structure, each hexagon containing a hexagonal hole with a water moleculet. 相似文献
85.
Ahmed Yahia Polly L. Arnold Prof. Dr. Jason B. Love Dr. Laurent Maron Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(16):4881-4888
A theoretical investigation of the reductive oxo‐group silylation reaction of the uranyl dication held in a Pacman macrocylic environment has been carried out. The effect of the modeling of the Pacman ligand on the reaction profiles is found to be important, with the dipotassiation of a single oxo group identified as a key component in promoting the reaction between the Si? X and uranium–oxo bonds. This reductive silylation reaction is also proposed to occur in an aqueous environment but was found not to operate on bare ions; in this latter case, substitution of a ligand in the equatorial plane was the most likely reaction. These results demonstrate the importance of the presence but not the identity of the equatorial ligands upon the silylation of the uranyl U? O bond. 相似文献
86.
Toshitaka Gamo 《Trends in analytical chemistry : TRAC》2011,30(8):1308-1319
The Sea of Japan, a semi-closed marginal sea (greatest depth ∼3700 m) in the northwestern-most Pacific Ocean, has an independent, deep convection system, which is driven by the formation and the sinking of cool, saline surface water towards the bottom in severe winters. Continuous measurement of dissolved oxygen using highly precise versions of the Winkler titration method has revealed 8-10% decreases in the bottom concentration of oxygen (O2) over the past 30 years. The temporal decrease in O2 means an imbalance between the supply of O2 from the surface and the in situ consumption of O2 in decomposing organic matter, suggesting that the change in the deep convection pattern of the Sea of Japan is probably caused by global climate change to reduce winter cooling of surface seawater. 相似文献
87.
A. I. Komyak A. P. Zazhogin D. S. Umreiko A. A. Lugovsky 《Journal of Applied Spectroscopy》2009,76(2):167-173
Electronic absorption spectra of nanoclusters of uranium tetrachloride are obtained experimentally and analyzed over a wide
spectral range, from the visible to the IR. The structure of the long wavelength electronic absorption spectra is discussed
in terms of the structure and electron-donor number of the attached ligand. Molecules of dimethyl sulfoxide (DMSO), hexamethyl
phosphotriamide (HMPT), and water were used as ligands. The effect of the symmetry of the surroundings of the U4+ ion on the structure of the electronic spectrum is examined.
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 76, No. 2, pp. 182–187, March–April 2009. 相似文献
88.
小孔周期性泄流的实验与分析 总被引:8,自引:2,他引:6
通过对小孔泄流的周期性研究.发现泄流周期随着时间进程变化趋于增大,小孔的直径越大泄流周期越小,不相容的液体间不能形成小孔周期性泄流,并分析了有关现象. 相似文献
89.
Summary In high-Z atoms, quantum electrodynamic (QED) corrections are an important component in the theoretical prediction of atomic energy levels. The main QED effects in electronic atoms are the one-electron self-energy and vacuum-polarization corrections which are well known. At the next level of precision, estimates of the effect of electron interactions on the self energy and higher-order effects in two exchanged photon corrections are necessary. These corrections can be evaluated within the framework of QED in the bound interaction picture. For high-Z few-electron atoms, this approach provides a rapidly converging series in 1/Z for the corrections, which is the generalization of the well-known relativistic 1/Z expansion methods. This paper describes recent work on the effect of electron interactions on the self energy. The QED effects are particularly important for the theory for lithiumlike uranium where an accurate measurement of the Lamb shift has been made, as well as for numerous other cases where systematic differences appear between theory that does not include these QED effects and experiment. 相似文献
90.
企业合作在“双循环”新发展格局下呈现出更多的模糊特征,能否形成稳定的模糊合作格局及持续合作的收益再分配策略成为合作联盟的关注点。将广义模糊超量博弈和模糊凸博弈及其广义解集应用到“双循环”新发展格局下企业联盟合作与收益再分配中,提出最大广义模糊超量博弈模型及其广义模糊谈判集,并基于最大广义模糊超量博弈均衡性的视角,对模糊凸博弈下广义模糊谈判集与核心的等价性质进行论证。研究结果不仅满足了“双循环”新发展格局下合作企业以部分资源参与合作的意愿,及企业联盟模糊凸合作博弈下再分配方案等价性证明需求,而且实现了保留部分收益用于联盟再发展的策略。 相似文献