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111.
Inside Back Cover: From Biomass‐Derived Furans to Aromatics with Ethanol over Zeolite (Angew. Chem. Int. Ed. 42/2016) 下载免费PDF全文
112.
Metal Complexes of a Boron‐Dipyrromethene (BODIPY)‐Tagged N‐Heterocyclic Carbene (NHC) as Luminescent Carbon Monoxide Chemodosimeters 下载免费PDF全文
Pavlo Kos Prof. Dr. Herbert Plenio 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(3):1088-1095
Several metal complexes with a boron dipyrromethene (BODIPY)‐functionalized N‐heterocyclic carbene (NHC) ligand 4 were synthesized. The fluorescence in [( 4 )(SIMes)RuCl2(ind)] complex is quenched (Φ=0.003), it is weak in [( 4 )PdI2(Clpy)] (Φ=0.033), and strong in [( 4 )AuI] (Φ=0.70). The BODIPY‐tagged complexes can experience pronounced changes in the brightness of the fluorophore upon ligand‐exchange and ligand‐dissociation reactions. Complexes [( 4 )MX(1,5‐cyclooctadiene)] (M=Rh, Ir; X=Cl, I; Φ=0.008–0.016) are converted into strongly fluorescent complexes [( 4 )MX(CO)2] (Φ=0.53–0.70) upon reaction with carbon monoxide. The unquenching of the Rh and Ir complexes appears to be a consequence of the decreased electron density at Rh or Ir in the carbonyl complexes. In contrast, the substitution of an iodo ligand in [( 4 )AuI] by an electron‐rich thiolate decreases the brightness of the BODIPY fluorophore, rendering the BODIPY as a highly sensitive probe for changes in the coordination sphere of the transition metal. 相似文献
113.
Trifluoromethylselenolation of Aryldiazonium Salts: A Mild and Convenient Copper‐Catalyzed Procedure for the Introduction of the SeCF3 Group 下载免费PDF全文
Pavlo Nikolaienko Prof. Dr. Magnus Rueping 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(8):2620-2623
The straightforward introduction of the trifluoromethylseleno group into aromatic and heteroaromatic compounds is accomplished by the utilization of readily available aryldiazonium tetrafluoroborates, potassium selenocyanate, and Ruppert–Prakash reagent. The reaction tolerates a wide range of aromatic and heteroaromatic diazonium salts and is also amenable to the synthesis of pentafluoroethyl selenoethers. Furthermore, the methodology can be applied directly starting from anilines. 相似文献
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Valentyn A. Tatarenko Pavlo O. Selyshchev Olena V. Oliinyk Yong Bum Park 《哲学杂志》2013,93(24):2724-2749
A kinetic model for the influence of external noises such as fluctuations of the vacancies’ generation rate and inhomogeneity of irradiated f.c.c. crystal on the formation of nanoscale modulated dissipative structure in a spatial distribution of vacancies is considered. The generation rate of vacancies all over the sites and a density of their dislocation-type sinks are modelled as independent random uniform stationary fields and with certain defined parameters of fluctuation correlations – spatial and temporal ones. Such stochastic fields can induce a spatial redistribution of vacancies that can lead to their density stationary uniform field or stochastic one. By the average value and correlation functions of these fluctuations, the conditions are determined for interacting fluctuations of the vacancies’ density, under which this homogeneous random field becomes unstable in relation to the stochastic field with a spatially periodic mean distribution of vacancies’ density. For instance, with f.c.c. nickel as a model of the irradiated functional material, the temperature dependence of spatial period d(T) of the modulated dissipative structure of vacancies’ subsystem in f.c.c. crystal is numerically forecasted and analysed, taking into account the total (‘electrochemical’?+?‘strain-induced’) interaction between vacancies. Such d(T)-dependence is also determined by the kinetic characteristics of vacancies’ redistribution. 相似文献
116.
Dr. Shaohua Liu Dr. Jian Zhang Dr. Renhao Dong Dr. Pavlo Gordiichuk Dr. Tao Zhang Dr. Xiaodong Zhuang Prof. Yiyong Mai Prof. Feng Liu Prof. Andreas Herrmann Prof. Xinliang Feng 《Angewandte Chemie (International ed. in English)》2016,55(40):12516-12521
Despite the availability of numerous two‐dimensional (2D) materials with structural ordering at the atomic or molecular level, direct construction of mesoscale‐ordered superstructures within a 2D monolayer remains an enormous challenge. Here, we report the synergic manipulation of two types of assemblies in different dimensions to achieve 2D conducting polymer nanosheets with structural ordering at the mesoscale. The supramolecular assemblies of amphipathic perfluorinated carboxylic acids and block co‐polymers serve as 2D interfaces and meso‐inducing moieties, respectively, which guide the polymerization of aniline into 2D, free‐standing mesoporous conducting polymer nanosheets. Grazing‐incidence small‐angle X‐ray scattering combined with various microscopy demonstrates that the resulting mesoscale‐ordered nanosheets have hexagonal lattice with d‐spacing of about 30 nm, customizable pore sizes of 7–18 nm and thicknesses of 13–45 nm, and high surface area. Such template‐directed assembly produces polyaniline nanosheets with enhanced π–π stacking interactions, thereby resulting in anisotropic and record‐high electrical conductivity of approximately 41 S cm?1 for the pristine polyaniline nanosheet based film and approximately 188 S cm?1 for the hydrochloric acid‐doped counterpart. Our moldable approach creates a new family of mesoscale‐ordered structures as well as opens avenues to the programmed assembly of multifunctional materials. 相似文献
117.
Thermal lattice Boltzmann simulations are prone to severe numerical instabilities. While octagonal velocity lattices increase the range of temperatures that can be successfully simulated, the ranges are insufficient for many applications. Second order interpolation is required to correlate diagonal streaming to the square spatial grid. Here, the role of energy-dependent octagonal lattices is examined, an idea spawned from Gauss–Hermite quadratures. A nontrivial allocation scheme is now required to ensure moment conservation in connecting to the spatial grid. For the energy-dependent lattices, it is shown that there are no lower bounds to the temperature, thus allowing for higher Reynolds number simulations. Simulations are presented and compared to theory (viscosity and sound speed dependence on temperature) showing excellent agreement. 相似文献
118.
J. Preinhaelter J. Urban P. Pavlo V. Shevchenko M. Valovic The MAST TEAM L. Vahala G. Vahala 《Czechoslovak Journal of Physics》2004,54(3):C116
The effect of the direction of the detected beam on the intensity of electron cyclotron emission (ECE) is studied. It is found that the combined effects of the strong dependence of the conversion efficiency of O mode at the plasma resonance on the direction of the incident wave and the partial screening of the beam waist by the vessel wall of the spherical tokamak MAST, can be responsible for the weakening of ECE for some frequencies. 相似文献
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120.
Letters in Mathematical Physics - We construct the general solution of a class of Fuchsian systems of rank N as well as the associated isomonodromic tau functions in terms of semi-degenerate... 相似文献