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71.
The complex [Rh(I(t)Bu)(2)HCl] has been shown to be an active catalyst in the hydrosilylation of carbonyl and imine complexes. This reactivity, combined with the previously reported H/D exchange catalyzed by these complexes allows for a one pot, two step reaction using a single catalyst for both H/D exchange and hydrosilylation. Using triethylsilane, [Rh(I(t)Bu)(2)Cl] catalyst, and D(2) gas, deuterated silyl-ethers can be synthesized in an atom-economical, solvent-free reaction.  相似文献   
72.
The phase behaviour of the lyotropic liquid crystal sodium 3,4,5-tris(omega-acryloyloxyundecyloxy)-benzoate was investigated by small angle X-ray scattering. The water content of the lyotropic liquid crystal phase was varied between 8 and 20wt% and the investigations were performed in a temperature range up to 70oC. A reversed hexagonal structure (H2-phase) as well as the isotropic phase were observed. The lattice constant of the H2-phase was found to be independent of the water content. An extremely small dependence on temperature could be found. Based on the shape of the molecules and the observed structural properties, a model for the arrangement of the molecules within the H2-phase is given. The transition temperature from the H2-phase to the isotropic phase decreases significantly from 60oC for the sample with 8wt% water content to 30oC for the sample with 20wt% water content.  相似文献   
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74.
Summary. Among the most promising fluorescent materials for sensor applications, anthracene and its derivatives have been widely studied. In this contribution, the synthesis and characterization of a series of isomers of bis(hydroxyphenyl)anthracene derivatives are described. The preparation of the corresponding derivatives via Suzuki cross-coupling reactions is presented with particular emphasis on finding appropriate protecting groups and studying the influence of the position of the hydroxy group on the outcome of the reaction. Moreover, the effects of protonation and deprotonation on absorption and emission spectra are reported and correlated to semi-empirical quantum mechanical calculations.  相似文献   
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Human serum albumin (HSA) and immunoglobulin G (IgG) represent over 75% of all proteins present in human plasma. These two proteins frequently interfere with detection, determination and purification of low abundance proteins that can be potential biomarkers and biomarker candidates for various diseases. Some low abundance plasma proteins such as clotting factors and inhibitors are also important therapeutic agents. In this paper, the characterization of ion-exchange monolithic supports under overloading conditions was performed by use of sample displacement chromatography (SDC). If these supports were used for separation of human plasma, the composition of bound and eluted proteins in both anion- and cation-exchange mode is dependent on column loading. Under overloading conditions, the weakly bound proteins such as HSA in anion-exchange and IgG in cation-exchange mode are displaced by stronger binding proteins, and this phenomenon was not dependent on column size. Consequently, small monolithic columns with a column volume of 100 and 200 μL are ideal supports for high-throughput screening in order to develop new methods for separation of complex mixtures, and for sample preparation in proteomic technology.  相似文献   
77.
Functional monolayers : RuII and OsII bis‐terpyridine complexes have been attached through a piperazine‐supported dithiocarbamate to a gold substrate (see picture). The robust tether, and the favourable reduction in oxidation potential induced by the electron‐rich piperazine result in self‐assembled monolayers with excellent reversible redox behaviour and exceptional stability.

  相似文献   

78.
We characterize several classes of graphs which satify a richness condition (R) and a condition (F) which concerns forbidden subgraphs. In particular we treat the case where (R) is: Each two vertices have a common neighbor. And this in combination with (F): G has no 5-circle C 5 resp. no 6-circle C 6 as subgraph. Another result deals with the case where (R) and (F) concern existence or non-existence of circles C n .  相似文献   
79.
A new rod-like coordination polymer consisting of (Ru-(terpy)2) motifs bridged by bithiophene units has been prepared by electrochemical polymerisation in acidic organic medium.  相似文献   
80.
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