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991.
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Tamás KálaiMark R. Fleissner József Jek?Wayne L. Hubbell Kálmán Hideg 《Tetrahedron letters》2011,52(21):2747-2749
New pyrroline nitroxides attached to a terminal acetylenic sulfone, a dibenzocyclooctyne or a cyclooctyne carboxylic acid were synthesized and tested in Cu-free click reactions to conjugate these new spin labels with 4-azido-TEMPO, azidophenylalanine and an azidophenylalanine-containing protein. 相似文献
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LI Ming LI Wei-Hua YANG Xing-Fan PAN Qing XIANG Dao HUANG Wen-Hui TANG Chuan-Xiang LIN Yu-Zheng 《中国物理C(英文版)》2010,34(2)
Magnetic bunch compressor is one of the key technologies on the path to next generation accelerator driven facilities. In this paper we report the design principles and the first experimental research of the bunch compressor developed at Chinese Academy of Engineering Physics (CAEP). The length of the bunch after compressor is found to be about 0.7 ps (rms) and the peak current exceeds 500 A when operated in the optimized condition. The sensitivity of the bunch length on the phase of the acceleration field and magnetic field of the bunch compressor was also measured and analyzed. 相似文献
997.
Takako Toda Hiroshi Igarashi Masahiro Watanabe 《Journal of Electroanalytical Chemistry》1999,460(1-2)
The design of high performance cathode electrocatalysts is essential for polymer–electrolyte fuel cells, which are now attracting enormous interest as a primary power source for zero-emission electric vehicles. We have discovered a significant enhancement of electrocatalytic activity of Pt by alloying with Fe, and found a maximum activity at ca. 50% Fe content, which results in 25 times higher activity than pure Pt activity. It was confirmed experimentally at Pt–Fe bulk alloys that the alloy catalyst surface consists of a pure Pt skin-layer (<1 nm in thickness) that is modified in the electronic structure by that of the bulk alloy. The enhancement could be well explained by the 5d-vacancy of the surface, but not by Pt interatomic distance or roughening of the surfaces. 相似文献
998.
I. V. Dobrynina 《Mathematical Notes》2000,68(3):306-311
In this paper, the problem of finite width for free products of groups with amalgamated subgroup is considered.
Translated fromMatematicheskie Zametki, Vol. 68, No. 3, pp. 353–359, September, 2000. 相似文献
999.
Alcohols and phenols were efficiently acylated with acetic anhydride in the presence of vanadyl sulfate (VOSO4.3H2O) at room temperature in high yields. 相似文献
1000.
Oxygen spillover through the gas phase was investigated, using FTIR spectroscopy to measure the reaction kinetics of the oxidation
of benzoic acid, adsorbed to γ-alumina, in the absence and presence of a neighboring Pt grid. It could be shown that oxygen,
activated on Pt may increase the oxidation rate, though there is no contact between Pt and the benzoic acid. 相似文献