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Russian Journal of Organic Chemistry - New data since about 2010 concerning complex formation of phosphorus-containing cyclophanes and cryptands with transition metals, as well as guest-host...  相似文献   
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A condensation of bis(hydroxymethyl)arylphosphines with 3- and 4-aminobenzonitriles leads to the corresponding 3,7-diaryl-1,5-bis(cyanophenyl)-1,5-diaza-3,7-diphosphacyclooctanes. Acyclic (aryl)bis[N-(2-cyanophenyl)aminomethyl]phosphines are formed in the case of 2-aminobenzonitrile. Molecular and crystalline structure of the compounds obtained was studied by X-ray diffraction analysis.  相似文献   
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Russian Chemical Bulletin - The steric and electronic structures of 1,3-diaza-5-phoaphacyclohexane with the pyridyl substituent at the phosphorus atom and a series of model...  相似文献   
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High-temperature persistent spectral hole-burning (PSHB), up to room temperature, has been observed in a Eu 3+ -doped aluminosilicate glass using a high peak-power nanosecond dye laser. Spontaneous refilling as well as thermal cycling measurements show that at least two mechanisms, a fast and a slow one, are involved in our sample. We suggest that the fast or “easy” component may correspond to a non-photochemical local rearrangement of the host or to photoreduction of the Eu 3+ ions and that the second one leading to very stable photoproducts may correspond to transfer of an electron over a sizable distance through a several-step process. The mechanisms we suggest agree with light-induced hole refilling measurements. Line broadening mechanisms are discussed and the temperature-dependent part of the homogeneous width and of the spectral shift is interpreted in terms of a two-phonon (Raman) process involving pseudo-local phonons. Received 28 July 1999  相似文献   
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The efficiency of a series of nickel complexes of P,N-cyclic ligands (potential catalysts in hydrogen fuel cells) in the electrocatalytic reduction of H+ to hydrogen and the oxidation of H2 in the coordination shell/cavity of the catalyst in DMF (acetonitrile with variable nickel: ligand ratio (1: 1, 1: 2) and different counterions (X=Cl and BF4)) was tested, and the most favorable conditions and structures were determined. The relation between the activity of the catalysts and the values of the electrochemical gap was found.  相似文献   
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The dependency of the critical Marangoni number on the geometrical aspect ratio of the floating half zone is essential to predict the onset of oscillatory thermocapillary convection.The experimental studies in the microgravity conditions on floating half zones of several centimeters in diameter have predicted that the critical Marangoni number increases with the increasing aspect ratio,and the terrestrial experimental studies have predicted the contradictory conclusion for floating half zones of several mil...  相似文献   
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