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Chen S Doolen G Herring JR Kraichnan RH Orszag SA She ZS 《Physical review letters》1993,70(20):3051-3054
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The enantioselective synthesis of the potent, selective, cytotoxic, annonaceous acetogenin, (+)-gigantecin, has been completed. An asymmetric glycolate aldol serves to establish the stereocenters at C13,14 and at C21,22. A Carreira asymmetric acetylide addition is used to establish the C17 stereocenter. 相似文献
24.
Zhen‐Ting Du Guo‐Ren Yue An‐Pai Li Jun‐Ying Ma Tong‐Xing Wu Xue‐Gong She Xin‐Fu Pan 《中国化学会会志》2004,51(3):505-508
A facile total synthesis of (±)‐nimbiol 1 has been achieved. In order to decrease the dioxo byproduct 2a , an improved oxidation system of CrO3/H2O/HOAc/NaOAc was used. 相似文献
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[see reaction]. This paper describes an enantioselective epoxidation of terminal olefins using chiral ketone 3 as catalyst and Oxone as oxidant. Up to 85% ee has been obtained. 相似文献
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Shou Xian She 《Optical and Quantum Electronics》1991,23(8):1045-1054
We present a simple and accurate method for characteristic analysis of metal-clad dielectric waveguides and absorptive waveguides. The real partN of the complex modal indexN=N + iN is obtained by solving the corresponding real eigenvalue equation, and the imaginary partN is given by (n/), where= + i is the complex dielectric constant of the absorptive layer, and N/ is obtained by numerical differentiation. The method is straightforward, and the cumbersome solution of complex transcendental equations is completely eliminated. Results for simple structures are in good agreement with those obtained by exact analysis. 相似文献
28.
Frontispiece: Glycoluril‐Derived Molecular Clips are Potent and Selective Receptors for Cationic Dyes in Water
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Tao Jia Weilong Zhou Fenghong Li Yajun Gao Lu Wang Jianxiong Han Jingying Zhang Yue Wang 《中国科学:化学(英文版)》2015,(2):323-330
Three alcohol/water-soluble porphyrins,Zn-TPy PMe I:zinc(II)meso-tetra(N-methyl-4-pyridyl)porphyrin tetra-iodide,ZnTPy PAd Br:zinc(II)meso-tetra[1-(1-adamantylmethyl ketone)-4-pyridyl]porphyrin tetra-bromide and Mn Cl-TPy PAd Br:manganese(III)meso-tetra[1-(1-adamantylmethyl ketone)-4-pyridyl]porphyrin tetra-bromide were employed as cathode interlayers to fabricate polymer solar cells(PSCs).The PC71BM([6,6]-phenyl C71 butyric acid methyl ester)and PCDTBT(poly[N-9″-hepta-decanyl-2,7-carbazole-alt-5,5-(4′,7′-di-2-thienyl-2′,1′,3′-benzothiadiazole)])-blend films were used as active layers in polymer solar cells(PSCs).The PSCs with alcohol/water-soluble porphyrins interlayer showed obviously higher power conversion efficiency(PCE)than those without interlayers.The highest PCE,6.86%,was achieved for the device with Mn ClTPy PAd Br as an interlayer.Ultraviolet photoemission spectroscopic(UPS),carrier mobility,atomic force microscopy(AFM)and contact angle( )characterizations demonstrated that the porphyrin molecules can result in the formation of interfacial dipole layer between active layer and cathode.The interfacial dipole layer can obviously improve the open-circuit voltage(Voc)and charge extraction,and sequentially lead to the increase of PCE. 相似文献