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91.
Emil Pfeiffer 《Analytical and bioanalytical chemistry》1885,24(1):410-410
92.
Mathematische Zeitschrift - 相似文献
93.
Emil Zdarek 《Fresenius' Journal of Analytical Chemistry》1902,41(9):553
Ohne Zusammenfassung 相似文献
94.
Emil Berglund 《Fresenius' Journal of Analytical Chemistry》1885,24(1):184-195
Ohne Zusammenfassung 相似文献
95.
We establish the following converse to the Eidelheit theorem: an unbounded closed and convex set of a real Hilbert space may be separated by a closed hyperplane from every other disjoint closed and convex set, if and only if it has a finite codimension and a non-empty interior with respect to its affine hull. 相似文献
96.
97.
Emil S. Koteles 《Fiber and Integrated Optics》1999,18(4):211-244
A review is presented of state-of-the-art optical planar waveguide demultiplexers (DEMUXes), that is, phasars (arrayed waveguide) and etched grating devices designed for high-density (narrow channel spacing) wavelength division multiplexing (WDM) systems. Their advantages and disadvantages are discussed in comparison with other techniques for demultiplexing WDM signals. The advances made in their performance are reviewed, and ultimate limitations, set by technological constraints, are proposed. Finally, a comparison is made of the advantages and disadvantages of etched grating as opposed to phasar planar waveguide DEMUXes. 相似文献
98.
99.
Thomas RM Widger PC Ahmed SM Jeske RC Hirahata W Lobkovsky EB Coates GW 《Journal of the American Chemical Society》2010,132(46):16520-16525
A highly active enantiopure bimetallic cobalt complex was explored for the enantioselective polymerization of a variety of monosubstituted epoxides. The polymerizations were optimized for high rates and stereoselectivity, with s-factors (k(fast)/k(slow)) for most epoxides exceeding 50 and some exceeding 300, well above the threshold for preparative utility of enantiopure epoxides and isotactic polyethers. Values for mm triads of the resulting polymers are typically greater than 95%, with some even surpassing 98%. In addition, the use of a racemic catalyst allowed the preparation of isotactic polyethers in quantitative yields. The thermal properties of these isotactic polyethers are presented, with many polymers exhibiting high T(m) values. This is the first report of the rapid synthesis of a broad range of highly isotactic polyethers via the enantioselective polymerization of racemic epoxides. 相似文献
100.
A broadly useful acid-labile traceless azido linker for the solid-phase synthesis of NH-1,2,3-triazoles is presented. A variety of alkynes were efficiently immobilized on a range of polymeric supports by Cu(I)-mediated azide-alkyne cycloadditions. Supported triazoles showed excellent compatibility with subsequent peptide chemistry. Release of pure material (typically >95%) from the solid support was readily achieved by treatment with aqueous TFA. 相似文献