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191.
192.
The N?N bond of molecular dinitrogen bridging two molybdenum atoms in the pentamethylcyclopentadienyl molybdenum complexes that bear ferrocenyldiphosphine as an auxiliary ligand is homolytically cleaved under visible light irradiation at room temperature to afford two molar molybdenum nitride complexes. Conversely, the bridging molecular dinitrogen is reformed by the oxidation of the molybdenum nitride complex at room temperature. This result provides a successful example of the cleavage and formation of molecular dinitrogen induced by a pair of two different external stimuli using a single system assisted by molybdenum complexes bearing ferrocenyldiphosphine under ambient conditions.  相似文献   
193.
Sulfide solid electrolytes, which show high ion conductivity, are anticipated for use as electrolyte materials for all-solid-state batteries. One drawback of sulfide solid electrolytes is their low chemical stability in air. They are hydrolyzed by moisture and generate H2S gas. Substituting oxygen atoms for sulfur atoms in sulfide solid electrolytes is effective for suppression of H2S gas generation in air. Especially, the xLi2O·(75-x)Li2S·25P2S5 (mol%) glasses hardly generated H2S gas in air. However, substituting oxygen atoms for sulfur atoms caused a decrease in conductivity. The x?=?7 glass showed high chemical stability in air and maintained high conductivity of 2.5?×?10?4 S cm?1 at room temperature. Performance of cells using the 7Li2O·68Li2S·25P2S5 and the 75Li2S·25P2S5 glasses as solid electrolytes were compared. All-solid-state C/LiCoO2 cell using the 7Li2O·68Li2S·25P2S5 glass produced performance as good as that obtained using the 75Li2S·25P2S5 glass. Capacity retention and change of interfacial resistance of the former cell were superior to those of the latter cell after storage at 4.0 V and 60 °C. The diffusion of oxygen element into the 7Li2O·68Li2S·25P2S5 glass was less than that into the 75Li2S·25P2S5 glass after storage at the voltage of 4.0 V at 60 °C. Improvement of the stability of sulfide solid electrolytes to moisture was related to cell performance as well as an increase in conductivity.  相似文献   
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We report a new possibility for liquid crystalline organic semiconductors. These materials exhibit smectic liquid crystalline phases, in which the molecules assume a smectic molecular order by self-assembly. Because of the strong dispersion force among long alkyl chains, on cooling, smectic molecular order was retained at room temperature. A charge transport ability was also retained. The conductivity of a device having smectic liquid crystalline order is about 5×107 that of a device with no smectic order. The current - voltage characteristic of the device has a very sharp increase at low threshold voltage (5 V). A high carrier mobility of 1.8×10-2 was observed in the smectic phase of one of the compounds studied (e).  相似文献   
196.
An in-beam emission Mössbauer spectrum of 57Fe arising from the 56Fe(n, γ) 57Fe reaction in iron disulfide at room temperature was measured with a parallel plate avalanche counter. It was clearly observed that the nuclear reaction and the following process lead to the production of a new chemical species of iron different from the parent compound.  相似文献   
197.
We introduce a combined fully three-dimensional macroscopic/microscopic transport approach employing relativistic 3D-hydrodynamics for the early, dense, deconfined stage of the reaction and a microscopic non-equilibrium model for the later hadronic stage where the equilibrium assumptions are not valid anymore. Within this approach we study the dynamics of hot, bulk QCD matter, which is being created in ultra-relativistic heavy-ion collisions at RHIC. In particular, we perform a detailed analysis of the reaction dynamics, hadronic freeze-out, transverse flow and elliptic flow. PACS 25.75.-q; 24.10.Nz; 24.10.Lx  相似文献   
198.
Potential-modulation spectroelectrochemical methods at solid/liquid and liquid/liquid interfaces are reviewed. After a brief summary of the basic features and advantages of the methods, practical applications of potential-modulation spectroscopy are demonstrated using our recent studies of solid/liquid and liquid/liquid interfaces, including reflection measurements for a redox protein on a modified gold electrode and fluorescence measurements for various dyes at a polarized water/1,2-dichloroethane interface. For both interfaces, the use of linearly polarized incident light enabled an estimation of the molecular orientation. The use of a potential-modulated transmission-absorption measurement for an optically transparent electrode with immobilized metal nanoparticles is also described. The ability of potential-modulated fluorescence spectroscopy to clearly elucidate the charge transfer and adsorption mechanisms at liquid/liquid interfaces is highlighted.  相似文献   
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