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71.
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Characterization of laccase isoenzymes from the white‐rot fungus Ganoderma sp.En3 and synergistic action of isoenzymes for dye decolorization 下载免费PDF全文
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水电工程的建设一般投资大、周期长,受自然环境、技术手段和市场波动等内外部不确定因素影响较大,所以成本变动可能性很大。总承包商要避免成本风险带来的不利影响就必须了解项目成本变动的影响因素并采取有效措施。系统动力学通过动态分析和反馈来帮助决策者理解复杂系统的结构和特点。本文提出了运用系统动力学进行总承包成本风险识别的基本思路,从风险模型结构要素及作用机理方面进行了论述,运用Vensim PLE软件绘出风险结构图,建立了风险识别模型,揭示了风险因素及其内在联系,对成本风险进行反馈识别,从而降低项目成本中威胁的负面影响,提高总承包商对建设项目的管理水平。 相似文献
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Chemical composition,antibacterial and antioxidant activity of the essential oils of Metaplexis japonica and their antibacterial components 下载免费PDF全文
Li Na Shi Da Ren Qiu Xiang Li Dong Sheng Wei Ya Mei Zhang Jian Chun Qin 《International Journal of Food Science & Technology》2015,50(2):449-457
The aim of this research was to determine the chemical composition, antioxidant and antibacterial properties of the essential oils from Metaplexis japonica and isolation of antibacterial constituents from the essential oils. Results showed that 63 components were identified in essential oils. Phenylethyl alcohol (77.978%), α‐terpineol (31.810%) and docosane (21.644%) were the most abundent constituents of flower oil, leaf oil and fruit oil, respectively. Based on bioactivity‐guided fractionation, three active constituents were isolated and identified as phenylethyl alcohol, α‐terpineol and β‐linalool. Both flower oil and phenylethyl alcohol showed high antibacterial performance, with inhibition zone from 25 ± 0.5 to 11 ± 0.6 mm at highest concentration, and MIC values ranging from 0.125 to 2%. In both DPPH and ABTS assay, the oils showed moderate antioxidant activity. These results indicate potential efficacy of active constituents and essential oils of M. japonica to control food‐borne pathogenic and spoilage bacteria. 相似文献
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MiR-30a Inhibits the Epithelial—Mesenchymal Transition of Podocytes through Downregulation of NFATc3
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Jinfeng Han Huidong Fan Qingyang Zhang Qin Hu Thomas P. Russell Howard E. Katz 《Advanced functional materials》2021,31(5):2005901
Two donor–acceptor (D–A) polymers are obtained by coupling difluoro- and dichloro-substituted forms of the electron-deficient unit BDOPV and the relatively weak donor moiety dichlorodithienylethene (ClTVT). The conductivity and power factors of doped devices are different for the chlorinated and fluorinated BDOPV polymers. A high electron conductivity of 38.3 and 16.1 S cm−1 are obtained from the chlorinated and fluorinated polymers with N-DMBI, respectively, and 12.4 and 2.4 S cm−1 are obtained from the chlorinated and fluorinated polymers with CoCp2, respectively, from drop-cast devices. The corresponding power factors are 22.7, 7.6, 39.5, and 8.0 µ W m−1 K−2, respectively. Doping of PClClTVT with N-DMBI results in excellent air stability; the electron conductivity of devices with 50 mol% N-DMBI as dopant remained up to 4.9 S m−1 after 222 days in the air, the longest for an n-doped polymer stored in air, with a thermoelectric power factor of 9.3 µ W m−1 K−2. However, the conductivity of PFClTVT-based devices can hardly be measured after 103 days. These observations are consistent with morphologies determined by grazing incidence wide angle X-ray scattering and atomic force microscopy. 相似文献
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Applied Intelligence - G raph C onvolutional N etwork (GCN) has been commonly applied for semi-supervised learning tasks. However, the established GCN frequently only considers the given labels in... 相似文献