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94.
P. G. Siddheshwar R. K. Vanishree Anthony Christy Melson 《Transport in Porous Media》2012,92(2):277-288
The effects of temperature-dependent viscosity, gravity modulation and thermo-mechanical anisotropies on heat transport in
a low-porosity medium are studied using the Ginzburg–Landau model. The effect of gravity modulation is to decrease the Nusselt
number, Nu and variable viscosity leads to increase in Nu. The thermo-mechanical anisotropies have opposite effect on Nu with thermal anisotropy decreasing the heat transport. 相似文献
95.
Anthony Linden Teresa de Haro Cristina Nevado 《Acta Crystallographica. Section C, Structural Chemistry》2012,68(1):m1-m3
The molecule of the title compound, [AuCl(C27H36N2)], which belongs to a class of potentially catalytically active N‐heterocyclic carbene complexes, has crystallographic C2 symmetry and approximate C2v symmetry. The structure is isostructural with the CuI and AgI analogues. A previous report of the structure of the title compound as its toluene solvate [Fructos et al. (2005). Angew. Chem. Int. Ed. 44 , 5284–5288] has inaccurate geometry for the complex molecule as a consequence of probable incorrect refinement in the space group Cc, instead of C2/c [Marsh (2009). Acta Cryst. B 65 , 782–783]. The Au—C bond length of 1.998 (4) Å in the title compound is more consistent with the mean distance of 1.979 (14) Å found in 52 other reported [AuCl(carbene)] complexes than with the shorter distance of 1.942 (3) Å given for the refinement in the space group Cc for the toluene solvate and the value of 1.939 Å obtained from the recalculation of that structure in C2/c. 相似文献
96.
Arnaud Chevalier Dr. Cédrik Massif Prof. Pierre‐Yves Renard Dr. Anthony Romieu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(5):1686-1699
We describe the efficient synthesis and one‐step derivatization of novel, nonfluorescent azo dyes based on the Black Hole Quencher‐3 (BHQ‐3) scaffold. These dyes were equipped with various reactive and/or bioconjugatable groups (azido, α‐iodoacetyl, ketone, terminal alkyne, vicinal diol). The azido derivative was found to be highly reactive in the context of copper‐catalyzed azide–alkyne cycloaddition (CuAAC) reactions and allowed easy synthetic access to the first water‐soluble (sulfonated derivative) and aldehyde‐modified BHQ‐3 dyes, the direct preparation of which failed by means of conventional azo‐coupling reactions. The aldehyde‐ and α‐iodoacetyl‐containing fluorescence quenchers were readily conjugated to aminooxy‐ and cysteine‐containing peptides by the formation of a stable oxime or thioether linkage, respectively. Further fluorescent labeling of the resultant peptide conjugates with red‐ or far‐red‐emitting rhodamine or cyanine dyes through sequential and/or one‐pot bioconjugations, led to novel Förster resonance energy transfer (FRET) based probes suitable for the in vivo detection and imaging of urokinase plasminogen activator, a key protease in cancer invasion and metastasis. 相似文献
97.
Dr. Paul Smart Dr. Charles A. Mason Jason R. Loader Dr. Anthony J. H. M. Meijer Prof. Alastair J. Florence Dr. Kenneth Shankland Dr. Ashleigh J. Fletcher Dr. Stephen P. Thompson Dr. Michela Brunelli Dr. Adrian H. Hill Prof. Lee Brammer 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(11):3552-3557
98.
Mélanie Gardette Anthony Perthue Jean-Luc Gardette Tünde Janecska Enikő Földes Béla Pukánszky Sandrine Therias 《Polymer Degradation and Stability》2013
The behaviour of polyethylene with different contents in vinyl and t-vinylene groups have been studied by photooxidation with λ ≥ 300 nm light or by thermooxidation at a temperature of 100 °C. The oxidation was studied by infrared spectroscopy and it was shown that the same oxidation products were obtained, but with different relative concentrations depending on the conditions of ageing, i.e. photochemical or thermal conditions. The mechanisms by which the oxidation products are formed were recalled. The differences between photo- and thermo-oxidation were evidenced on the basis of the stability of ketones that do not accumulate in photochemical conditions, as a result of Norrish reactions. The influence of the initial amount of unsaturated groups on the rates of oxidation was characterized. It was shown that the concentration of unsaturations had no effect on the rate of photooxidation but dramatically influenced the stability in thermooxidative conditions. 相似文献
99.
Anthony Jolly Dandan Miao Maxime Daigle Jean‐Franois Morin 《Angewandte Chemie (International ed. in English)》2020,59(12):4624-4633
The solution‐phase synthesis is one of the most promising strategies for the preparation of well‐defined graphene nanoribbons (GNRs) in large scale. To prepare high quality, defect‐free GNRs, cycloaromatization reactions need to be very efficient, proceed without side reaction and mild enough to accommodate the presence of various functional groups. In this Minireview, we present the latest synthetic approaches for the synthesis of GNRs and related structures, including alkyne benzannulation, photochemical cyclodehydrohalogenation, Mallory and Pd‐ and Ni‐catalyzed reactions. 相似文献
100.
Elaine Tsui Anthony J. Metrano Yuto Tsuchiya Robert R. Knowles 《Angewandte Chemie (International ed. in English)》2020,59(29):11845-11849
We report a catalytic, light‐driven method for the intramolecular hydroetherification of unactivated alkenols to furnish cyclic ether products. These reactions occur under visible‐light irradiation in the presence of an IrIII‐based photoredox catalyst, a Brønsted base catalyst, and a hydrogen‐atom transfer (HAT) co‐catalyst. Reactive alkoxy radicals are proposed as key intermediates, generated by direct homolytic activation of alcohol O?H bonds through a proton‐coupled electron‐transfer mechanism. This method exhibits a broad substrate scope and high functional‐group tolerance, and it accommodates a diverse range of alkene substitution patterns. Results demonstrating the extension of this catalytic system to carboetherification reactions are also presented. 相似文献