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991.
Wen R Yan CJ Yan HJ Pan GB Wan LJ 《Chemical communications (Cambridge, England)》2011,47(24):6915-6917
The co-adsorption of trinitrotoluene (TNT), a typical π-electron acceptor, and triphenylene (TP), a typical π-electron donor, on a Au(111) surface was investigated by in situ Electrochemical Scanning Tunneling Microscopy (ECSTM). DFT calculations proved that parallelly stacked and well-overlapped TP and TNT molecules can form Donor-Acceptor dyads through intermolecular π-π charge transfer, which agree well with the experimental results in the present work. 相似文献
992.
A copper-mediated methylthiolation of aryl halides with the widely available DMSO is described. The procedure tolerates a series of functional groups such as methoxy, nitro, chloro, fluoro, trifluoromethyl, formyl and methoxycarbonyl groups. Thus, it represents a simple and facile methylthiolation procedure. 相似文献
993.
Nearly monodispersed magnetic Fe(3)O(4)@DFUR-LDH submicro particles containing the anticancer agent DFUR were prepared via a coprecipitation-calcination-reconstruction strategy of LDH materials over the surface of Fe(3)O(4) particles, and present well-defined core-shell structure, strong magnetization and obvious magnetically controlled drug delivery and release properties. 相似文献
994.
Chiral organophosphine-catalyzed enantioselective Rauhut-Currier reaction has been disclosed for the first time. With L-valine-derived phosphinothiourea, the intramolecular Rauhut-Currier reaction of bis(enones) was achieved in good yields (up to 99%) with excellent enantioselectivities (up to 99.4% ee). 相似文献
995.
Liu Y Liang C Zhou H Gao M Pan H Wang Q 《Chemical communications (Cambridge, England)》2011,47(6):1740-1742
A synergetic effect of K, Ti and F together on improving the reversible hydrogen storage properties of NaAlH(4) is found by intruding K(2)TiF(6) as catalyst precursor. Around 4.4 wt% of hydrogen can be released from the NaAlH(4)-0.025 K(2)TiF(6) sample within 40 min at 140 °C. 相似文献
996.
Kezhi Jiang Gaofeng Bian Yuanjiang Pan Guoqiao Lai 《International journal of mass spectrometry》2011,299(1):13-19
The dissociation chemistry of the ortho-, meta- or para-isomers of protonated S-methyl methoxyl- (or chloro-) benzenylmethylenehydrazine dithiocarboxylate, RPhCHN–NHC(S)–SCH3 (R = MeO– or Cl–), has been investigated by collision induced dissociation experiments and DFT theoretical calculations. The three methoxyl-substituted isomers were easily differentiated according to the different abundance of the characteristic ion at m/z 136, resulting from the varying reactivity of the (NSC)SCH3 elimination. This fragmentation is triggered by the positive charge upon protonation on the imine N2. Relative to the meta isomer, the positive charge on N2 in the para isomer is dispersed due to the electron donating resonance of the methoxyl group, which leads to higher energy barrier in the dissociation reaction and the less abundant product ion (m/z 136) in the MS/MS. (NSC)SCH3 elimination of the ortho- isomer is further suppressed due to both the resonance effect and the “ortho effect” (an intramolecular hydrogen bond), with much higher energy barrier and extremely lower abundance of the fragment ion (m/z 136, 0.4%). The chloro substituted isomers, however, are short of the above positional effects due to the weak electronic effect of the substituent, and share the similar tandem mass spectrum. 相似文献
997.
998.
999.
Liu C Pan J Li S Zhao Y Wu LY Berkman CE Whorton AR Xian M 《Angewandte Chemie (International ed. in English)》2011,50(44):10327-10329
1000.
Wang X Peng KQ Pan XJ Chen X Yang Y Li L Meng XM Zhang WJ Lee ST 《Angewandte Chemie (International ed. in English)》2011,50(42):9861-9865
Nanowire solar cells: Pt nanoparticle (PtNP) decorated C/Si core/shell nanowire photoelectrochemical solar cells show high conversion efficiency of 10.86 % and excellent stability in aggressive electrolytes under 1-sun AM 1.5 G illumination. Superior device performance is achieved by improved surface passivation of the nanowires by carbon coating and enhanced interfacial charge transfer by PtNPs. 相似文献