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991.
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1-Amino-5-naphtholisanimportantintermediateproductfororganicsynthesis'.Itwastraditionallysynthesizedfroma-nityonaphthalenebychemicalmethod.HO:wever,thechemicalmethodneedstwostepsandproducesalargequantityofwastewater,indicatingthehigherenergyconsumptionandpollution.Inthispaper,theelectrochemicalreductionofa-nitronaphthalenetol-amino-5-naphtholwasfirstputforward,theelectrochemicalreductioncharacteristicsofa-nitronaphthalenetol-amino-5-naphtholwerestudiedandthereactionmechanismwasproposedaswell.… 相似文献
995.
Yuan Zhang Han Luo Qixing Lu Qiaoyu An You Li Shanshan Li Zongyuan Tang Baosheng Li 《中国化学快报》2021,32(1):393-396
We studied the cascade nucleophilic addition reactions of 1,2,3-triazines with activated acetonitriles or ketones,which were used to construct highly substituted pyridines that are not easily accessed by conventional methods.The strategy addressed some structural diversity issues currently facing medicinal chemistry,and the resulting pyridines could be used as convenient precursors for the synthesis of related pharmaceuticals.In particular,our method was applied to the syntheses of the marketed drug etoricoxib and several biologically important molecules in a few steps. 相似文献
996.
Qingying Bu Gerard Buskes Alexey I. Popov Adi Tcaciuc Vladimir G. Troitsky 《Positivity》2013,17(2):283-298
We investigate the relationship between the diagonal of the Fremlin projective tensor product of a Banach lattice E with itself and the 2-concavification of E. 相似文献
997.
We establish a conjecture of Mumford characterizing rationally connected complex projective manifolds in several cases. 相似文献
998.
Combinatorial aspects of the Torelli–Johnson–Morita theory of surface automorphisms are extended to certain subgroups of the mapping class groups. These subgroups are defined relative to a specified homomorphism from the fundamental group of the surface onto an arbitrary group K. For K abelian, there is a combinatorial theory akin to the classical case, for example, providing an explicit cocycle representing the first Johnson homomophism with target Λ 3 K. Furthermore, the Earle class with coefficients in K is represented by an explicit cocyle. 相似文献
999.
Vladimir R. Rosenfeld Douglas J. Klein Josep M. Oliva 《Journal of mathematical chemistry》2012,50(7):2012-2022
Various sorts of isomer enumeration problems are addressed in the context of polycarboranes, with special illustrative focus on the case of dicarboranes, for which then various numerical results are given. A systematic and general Pólya-theoretic methodology is used to make the computations, including some new techniques being applicable to a wide range of nano-structures built from a framework of like local subunits. 相似文献
1000.
Ir(ppy)2(VPHD) (ppy=2-phenyl pyridine, VPHD=6-(4-vinylphenyl)-2,4-hexanedione) was copolymerized with methyl methacrylate (MMA). The copolymer had high quantum yield of 52.3±0.5% in dilute ethyl acetate solution, and the yield increased around 45% than that of the iridium monomer. The maximum emission peaks for the copolymers shifted from 515 to 489 nm while the iridium complex content was less than 0.005 mol% in the feed. The blue emission at 489 nm and the green emission at 520 nm were analyzed by Lorenz function. They are attributed to 1MLCT and 3MLCT emissions, respectively. 相似文献