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381.
Polyaniline nanowires (PANI NWs) were deposited onto fluorine-doped tin oxide (FTO) glass substrate using the cyclic voltammetric method with aniline monomer precursor in HCl aqueous solution. The secondary oxidation peak plays an important role in polymerization of aniline monomer and the optimization of catalytic activity of PANI-based counter electrodes was achieved by controlling the number of cycles. The photovoltaic performance of the dye-sensitized solar cells (DSSCs) with PANI NWs counter electrodes (CEs) was optimized at 4th cycles, and then following parameters were obtained: Jsc = 17.2 mA cm−2, Voc = 0.71 V, FF = 59.3%, and efficiency (η) = 7.24%. While, Jsc = 14.7 mA cm−2, Voc = 0.77 V, FF = 70.6%, and efficiency (η) = 7.98% in cells with Pt CEs. The PANI NWs were attractive as an alternative CEs for the low-cost DSSCs instead of Pt.  相似文献   
382.
The anomalous magnetic moment of the negative muon has been measured to a precision of 0.7 ppm (ppm) at the Brookhaven Alternating Gradient Synchrotron. This result is based on data collected in 2001, and is over an order of magnitude more precise than the previous measurement for the negative muon. The result a(mu(-))=11 659 214(8)(3) x 10(-10) (0.7 ppm), where the first uncertainty is statistical and the second is systematic, is consistent with previous measurements of the anomaly for the positive and the negative muon. The average of the measurements of the muon anomaly is a(mu)(exp)=11 659 208(6) x 10(-10) (0.5 ppm).  相似文献   
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A nucleophile screening for the organocatalyzed enantioselective Reissert-type dearomatization of quinoline derivatives using chiral triazoles as anion-binding catalysts was realized. Our recently reported helical tetrakis(triazole) catalysts (TetraTri) have proven to be highly active in this type of reactions, however the methods were limited to nucleophiles with a N value of 10 according to the Mayr's nucleophilicity scale. In this study, different carbon-nucleophiles of varied nucleophilicity N-values were explored, allowing the identification of potential novel reaction partners with N >5 such as ketene thioacetals. Thus, a number of chiral 1,2-dihydroisoquinoline-thioesters with an enantioselectivity up to 92:8 er. were synthetized, which could easily be transformed into a more valuable amide derivative.  相似文献   
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The phytochemical investigation of the lichen Parmotrema sancti-angelii afforded three racemic compounds, sanctis A–C, which feature an original dibenzo-2,8-dioxabicyclo[3.3.1]nonane scaffold. These compounds were structurally characterized by extensive NMR spectroscopy analyses, comparison between experimental and theoretical NMR spectroscopic data, and X-ray crystallography. These metabolites are similar to procyanidin A and display a methyl group instead of a pendant aromatic ring at C-9, a so far unprecedented structural feature. A biosynthetic route to sanctis A–C is proposed.  相似文献   
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Unlike the saturated aliphatic and aromatic alcohols, allyl alcohol under the same conditions reacts with polyfluoroalkyl chlorosulfites to form not ethers, but polyfluorinated alcohols. The exception is polyfluoroalkyl chlorosulfites with the chain length of more than five carbon atoms. Allyl ethers of polyfluorinated alcohols of general formula CH2=CHCH2OCH2(CF2CF2)nH (n = 1–3) were obtained, when the reaction proceeded in the presence of potassium carbonate, owing to its participation in a specific orientation of the reaction centers in the resulting intermediate structure, which is easily transformed into allyl ethers of polyfluorinated alcohols.  相似文献   
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