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Abstract: An organic–inorganic hybrid solar cell based on CdSe quantum dots (QDs) and poly(3-hexylthiophene) (P3HT) was fabricated. Its temperature-dependent photovoltaic behaviors, such as I–V characteristic curves and open circuit voltage (V oc) transient response, were measured. The photovoltaic behavior of this hybrid thin film device was similar with that of organic thin film solar cells, according to analysis results based on the equivalent circuit method. The exact carrier lifetime was remarkably different between under low-temperature region and under temperature above 197K. [Copyright &y& Elsevier]

[Display omitted] • Two distinct geological ages of molybdenite are determined at Sanchakou. • Decreased temperature and f O2 contributed to porphyry-style ore formation. • High grade copper was likely attributed to overprinting mineralization event. • Identification of an old deformation-related porphyry Cu deposit in Xinjiang is helpful for guiding ore exploration. The Sanchakou Cu deposit is located in the eastern section of the Dananhu arc belt in Eastern Tianshan, Xinjiang, and recorded multiple magmatic-mineralization events. The porphyry-style mineralization period produced disseminated, sulfide-dominant veined, and patchy sulfides containing chalcopyrite ± bornite ± carrolite ± molybdenite (Mol-1), which was associated with magnetite ± biotite ± chlorite ± sericite alteration in a suite of quartz diorite intrusions. The overprinting mineralization period contributed to minor Cu and Mo mineralization, featured by later disseminated molybdenite (Mol-2), chalcopyrite, and widespread low-temperature (<280 °C) vein-type stellerite assemblages. Two distinct geological ages of molybdenite (including Mol-1 and Mol-2) from Sanchakou have been determined in this study. The old 187Re/187Os isochron age for euhedral Mol-1 represents the timing of original porphyry-style mineralization (386 ± 16 Ma), in agreement with LA-ICP-MS zircon U-Pb age of dark diorite dykes (390 ± 11 Ma). The young 187Re/187Os age for fine-grained Mol-2 is interpreted to be a maximum age of sulfide formation or remobilization (364 ± 15 Ma), most likely associated with the emplacement of Late Devonian gneissic granite intrusions. Fluid inclusion microthermometry, mineralogy, and physicochemical calculations for the porphyry-type mineralization period (including four stages) at Sanchakou suggest that earlier magmatic fluids have evolved from high T (310–460 °C), high log f O2 (−22 to − 26), and alkaline condition during stage I to low T, low log f O2 (−3 4), and acidic condition during stage II. The decrease of oxygen fugacity caused by abundant deposition of magnetite in stage I produced large-scale Cu and Mo precipitation. Stage II to IV fluids have gradually decreasing temperatures and salinities, due to involvement of meteoric water that also facilitates the ore deposition. This result is consistent with the evolution of O isotope compositions of the fluids (δ18O fluids = − 9.3 to 4.3), further implying the significance of fluid mixing instead of fluid boiling that caused ore deposition. Locally high-grade copper concentrations at Sanchakou are likely attributed to the overprinting modification event on the original ore bodies. All of these observations indicate that the Paleozoic Sanchakou ore-forming system is similar to other deformed porphyry Cu systems in the Central Asian orogenic belt (CAOB) and worldwide. The Cu mineralization and modification event at Sanchakou is coincident with the second peak productivity in CAOB. We further suggest that the Paleozoic diorite complex and stellerite alteration can be as a significant exploration target for porphyry-style Cu mineralization in the Eastern Tianshan. [ABSTRACT FROM AUTHOR]

Abstract: FR429 is an ellagitannin with a potential antitumor activity, isolated and purified from Polygonum capitatum Buch.-Ham.ex D.Don, which is a traditional Miao-nationality herbal medicine in Guizhou and Yunnan of China. Our preliminary result of pharmacology study has indicated that the antitumor activity of FR429. However, the metabolism of FR429 has not been reported yet. In this study, LC–ion trap-time of flight mass spectrometry (LC–IT-TOF/MS) was used to characterize unpredictable metabolites of FR429 biotransformed by intestinal bacteria in vitro. Total thirteen metabolites were detected and characterized via comparisons of their accurate molecular masses and fragment ions of each MS n stage with those of the parent drug, and four of them were also elucidated by NMR. The results demonstrated that FR429 could be transformed by intestinal bacteria in vitro, mainly via hydrolysis and reduction reaction. This work provided a basis for the further study on the biotansformation of FR429 in vivo. [Copyright &y& Elsevier]

Abstract: This study endeavored to investigate the variability of bacteria and fungi present during the fermentation process of the light-fragranced distilled liquor known as Fen liquor. To accomplish this, we used a combination of clone libraries of 16S rRNA genes, bar-coded pyrosequencing of the internal transcribed spacer region 1 (ITS1), and quantitative real-time PCR (qPCR). Fifteen families of bacteria and six families of fungi were detected. More than 91% of 16S rRNA gene sequences could be assigned to the family Lactobacillaceae, which were then classified to eight different operational taxonomic units (OTUs), based on a 3% cut-off. The most abundant OTU which contributed to 51% of the total 16S rRNA gene sequences was affiliated with Lactobacillus acetotolerans and had a significantly similar variation trend with the chemical constituents detected. Sixty percent of the fungal ITS1 region sequences were affiliated with the family Saccharomycetaceae. The most abundant OTU was very similar to Issatchenkia orientalis, which displayed notable similarities with respect to the change trends in both ethanol and organic acid contents. The sequences of the second most abundant OTU were closest to Saccharomyces cerevisiae, an important species in the process of ethanol production. Furthermore, about one fourth of the ITS1 region sequences belonged to the family Saccharomycopsidaceae. Conversely, very few sequences could be grouped together with filamentous fungi. The results of qPCR showed that the content of bacteria was increased while that of fungi was more stable in the fermentation process. It is very important to simultaneously investigate bacterial and fungal variations in food-fermentation processes. [Copyright &y& Elsevier]