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941.
Hong Yan Zhong‐Wei Hou Hai‐Chao Xu 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(14):4640-4643
A photoelectrochemical method for the C?H alkylation of heteroarenes with organotrifluoroborates has been developed. The merger of electrocatalysis and photoredox catalysis provides a chemical oxidant‐free approach for the generation and functionalization of alkyl radicals from organotrifluoroborates. A variety of heteroarenes were functionalized using primary, secondary, and tertiary alkyltrifluoroborates with excellent regio‐ and chemoselectivity. 相似文献
942.
研究曲面到复双曲空间CHn的调和映射,并证明CHn中的紧致共形极小曲面的亏格g>1。 相似文献
943.
Thioi-terminated oligonucleotide was immobilized to gold sur-face by self-assembly method. A novel amplification strategy was introduced for improving the sensitivity of DNA hybridiza-tion using biotin labeled protein-streptavidin network complex. This complex can be formed in a cross-linking network of molecules so that the amplification of the response signal will be realized due to the big molecular size of the complex. It could be proved from the impedance technique that this amplification strategy caused dramatic improvement of the detection sensitivi-ty. These results give significant advances in the generality and sensitivity as it is applied to biosensing. 相似文献
944.
Inthepreviouspaper',wedevelopedanewmodelforcorrelatingandpredictingthesolubilitiesofsolidsinsupercriticalfluids(SCFs),whichcanbegiveninthefollowingformin[yi/(l-"y,)]=njnon(RTdr)-'dp-inP BP C(l)wherethecoefficientofthepressuretermisgivenbyB=-n(RTd,')-,(2)InEqs(1)and(2),yZisthemolefractionofthesoluteinSCFphase,d.thebulkdensityofthesolvent,d,'thelocaldensityofthesolventsurroundingthesolute,Tabsollltetemperatllre,Ppressure,Rgasconstallt,andCconstant.Thevalidityofamodelshouldbeverifiedbycor… 相似文献
945.
CIMS环境下技术创新的组织 总被引:1,自引:0,他引:1
本文探讨了CIMS环境下企业技术创新的组织问题,提出了CIMS环境下技术创新的组织结构和组织形式,为CIMS环境下企业技术创新组织的重构提供了参考。 相似文献
946.
In this paper the theory is applied of the Q-neighborhood system of a fuzzy point, which was introduced in [3], and the fuzzy topological groups and their subgroups, normal subgroups and quotients are discussed. Then some results introduced in [1] and [7] are improved. 相似文献
947.
从北仑口岸进口的几种主要铁矿物相分析着手,讨论了铁矿的矿物组成对高频燃烧红外吸收法测定铁矿中硫含量的影响,为消除在个别矿种中硫的检测中存在的干扰提供理论依据。 相似文献
948.
949.
Hong Xia DING Wei LU Lei Xiang YANG Hai Bo LI Hua BAI Xiu Mei WU Jun Chao CAI Yu ZHAO 《中国化学快报》2006,17(1):5-8
Artabotrine 1 (Figure 1) was isolated from Artabotrys zeylanicus Hook.f. & Thoms., an endemic mainly in Sri Lanka1. The spectral data and single crystal X-ray analysis indicated that artabotrine is a novel and comparatively rare alkaloid characterized with N-methoxylated 4,5-dioxoaporphine, since most of the reported 4,5-dioxoaporphines are N-methylated or no substituted2-11. This highly oxidized aporphine alkaloid was found to possess notable inhibitory activity on P-388 leukemia cell lin… 相似文献
950.
The self-assembly of meso-tetra (N-methyl-4-pyridyl) porphyrine tetratosylat (H2TMPyP) on an iodide modified Cu(1 1 1) surface has been studied by means of in situ electrochemical-scanning tunneling microscopy (EC-STM). The I/Cu(1 1 1) surface was found to be a good substrate for the self-assembly of highly ordered layers of porphyrin cations. Furthermore, a reversible structural phase transition within the highly ordered porphyrin layer was observed during variation of the electrode potential, as a consequence of changing electronic properties of the substrate. 相似文献