资金价值(Value for Money,VfM)评价是PFI项目评价的重要标准,是判断公共项目是否采用私人主动融资(PFI)模式的核心问题。目前在国外PFI实践中已经得到了广泛的应用,对我国的PFI项目的评价有一定的借鉴意义。介绍了VfM的科学内涵和计算...资金价值(Value for Money,VfM)评价是PFI项目评价的重要标准,是判断公共项目是否采用私人主动融资(PFI)模式的核心问题。目前在国外PFI实践中已经得到了广泛的应用,对我国的PFI项目的评价有一定的借鉴意义。介绍了VfM的科学内涵和计算方法,并对VfM的构成要素PSC和LCC进行了详细分析。展开更多
A high performance polymer solar cells(PSCs) based on polymer donor PM6 containing fluorinated thienyl benzodithiophene unit and n-type organic semiconductor acceptor IT-4 F containing fluorinated end-groups were deve...A high performance polymer solar cells(PSCs) based on polymer donor PM6 containing fluorinated thienyl benzodithiophene unit and n-type organic semiconductor acceptor IT-4 F containing fluorinated end-groups were developed. In addition to complementary absorption spectra(300–830 nm) with IT-4 F, the PM6 also has a deep HOMO(the highest occupied molecular) level(-5.50 e V), which will lower the open-circuit voltage(V_(oc)) sacrifice and reduce the E_(loss) of the IT-4 F-based PSCs. Moreover, the strong crystallinity of PM6 is beneficial to form favorable blend morphology and hence to suppress recombination. As a result, in comparison with the PSCs based on a non-fluorinated D/A pair of PBDB-T:ITIC with a medium PCE of 11.2%, the PM6:IT-4 Fbased PSCs yielded an impressive PCE of 13.5% due to the synergistic effect of fluorination on both donor and acceptor, which is among the highest values recorded in the literatures for PSCs to date. Furthermore, a PCE of 12.2% was remained with the active layer thickness of up to 285 nm and a high PCE of 11.4% was also obtained with a large device area of 1 cm^2. In addition, the devices also showed good storage, thermal and illumination stabilities with respect to the efficiency. These results indicate that fluorination is an effective strategy to improve the photovoltaic performance of materials, as well as the both fluorinated donor and acceptor pair-PM6:IT-4 F is an ideal candidate for the large scale roll-to-roll production of efficient PSCs in the future.展开更多
A pot experiment was carried out by growing 29 different genotypes （Amaranthus spp.） of vegetable amaranth under low- （0.12 mg. kg-1） and middle- （0.40 mg · kg-1） cadmium （Cd） exposure. The result showed ...A pot experiment was carried out by growing 29 different genotypes （Amaranthus spp.） of vegetable amaranth under low- （0.12 mg. kg-1） and middle- （0.40 mg · kg-1） cadmium （Cd） exposure. The result showed that amaranth was vulnerable to cadmium （Cd） contamination in soil. Variations of Cd concentrations in both roots and edible parts among genotypes were significant （P 〈 0.001） in both treatments. Cd concentrations in edible parts of the tested genotypes grown under low- and middle-Cd levels were significantly correlated （p 〈 0.01）, implying that Cd- accumulating property of amaranth is genotype-dependent. Differences in Cd chemical forms between cv. Nanxing- dayemashixian （cv. Nan）, a selected typical pollution-safe cultivar （Cd-PSC）, and cv. Pennongjianyexian （cv. Pen）, a selected typical non-Cd-PSC, under different Cd exposure conditions were compared. It was found that the alternation of Cd in FNaC1 （Cd form extracted by 1 mol.L-1NaC1） may be a key factor in regulating Cd accumulation of different amaranth genotypes and that the protein-binding Cd is considered to be associated with Cd translocation. The results indicated that amaranth is capable of enduring high level of Cd pollution when grown as vegetable crop, and accordingly, consuming vegetable amaranth would bring high health risk. Therefore, adopting Cd-PSC strategy would help reducing the risk of Cd pollution in amaranth. In this study, cv. Nan was identified as a Cd-PSC and recommended to be applied production practice.展开更多
随着港口国监督(Port State Control简称PSC)检查制度的普遍实施,这项制度所存在的一些问题也凸现出来:PSC受到了外界非技术因素的强烈干预,PSC检查官的自由裁量权过大,PSC检查程序没有很好地执行,PSC制度本身的缺陷,等等。对这些问题...随着港口国监督(Port State Control简称PSC)检查制度的普遍实施,这项制度所存在的一些问题也凸现出来:PSC受到了外界非技术因素的强烈干预,PSC检查官的自由裁量权过大,PSC检查程序没有很好地执行,PSC制度本身的缺陷,等等。对这些问题进行数据和政策分析,挖掘这些问题的根源,并对PSC检查制度今后的发展方向进行探讨,对PSC制度更好的实施和发展有一定的参考意义。展开更多
文摘资金价值(Value for Money,VfM)评价是PFI项目评价的重要标准,是判断公共项目是否采用私人主动融资(PFI)模式的核心问题。目前在国外PFI实践中已经得到了广泛的应用,对我国的PFI项目的评价有一定的借鉴意义。介绍了VfM的科学内涵和计算方法,并对VfM的构成要素PSC和LCC进行了详细分析。
基金supported by the National Natural Science Foundation of China(51422306,51503135,51573120,91633301)Jiangsu Provincial Natural Science Foundation(BK20150332)T.P.Russell was supported by the U.S.Office of Naval Research(N00014-15-1-2244)
文摘A high performance polymer solar cells(PSCs) based on polymer donor PM6 containing fluorinated thienyl benzodithiophene unit and n-type organic semiconductor acceptor IT-4 F containing fluorinated end-groups were developed. In addition to complementary absorption spectra(300–830 nm) with IT-4 F, the PM6 also has a deep HOMO(the highest occupied molecular) level(-5.50 e V), which will lower the open-circuit voltage(V_(oc)) sacrifice and reduce the E_(loss) of the IT-4 F-based PSCs. Moreover, the strong crystallinity of PM6 is beneficial to form favorable blend morphology and hence to suppress recombination. As a result, in comparison with the PSCs based on a non-fluorinated D/A pair of PBDB-T:ITIC with a medium PCE of 11.2%, the PM6:IT-4 Fbased PSCs yielded an impressive PCE of 13.5% due to the synergistic effect of fluorination on both donor and acceptor, which is among the highest values recorded in the literatures for PSCs to date. Furthermore, a PCE of 12.2% was remained with the active layer thickness of up to 285 nm and a high PCE of 11.4% was also obtained with a large device area of 1 cm^2. In addition, the devices also showed good storage, thermal and illumination stabilities with respect to the efficiency. These results indicate that fluorination is an effective strategy to improve the photovoltaic performance of materials, as well as the both fluorinated donor and acceptor pair-PM6:IT-4 F is an ideal candidate for the large scale roll-to-roll production of efficient PSCs in the future.
文摘A pot experiment was carried out by growing 29 different genotypes （Amaranthus spp.） of vegetable amaranth under low- （0.12 mg. kg-1） and middle- （0.40 mg · kg-1） cadmium （Cd） exposure. The result showed that amaranth was vulnerable to cadmium （Cd） contamination in soil. Variations of Cd concentrations in both roots and edible parts among genotypes were significant （P 〈 0.001） in both treatments. Cd concentrations in edible parts of the tested genotypes grown under low- and middle-Cd levels were significantly correlated （p 〈 0.01）, implying that Cd- accumulating property of amaranth is genotype-dependent. Differences in Cd chemical forms between cv. Nanxing- dayemashixian （cv. Nan）, a selected typical pollution-safe cultivar （Cd-PSC）, and cv. Pennongjianyexian （cv. Pen）, a selected typical non-Cd-PSC, under different Cd exposure conditions were compared. It was found that the alternation of Cd in FNaC1 （Cd form extracted by 1 mol.L-1NaC1） may be a key factor in regulating Cd accumulation of different amaranth genotypes and that the protein-binding Cd is considered to be associated with Cd translocation. The results indicated that amaranth is capable of enduring high level of Cd pollution when grown as vegetable crop, and accordingly, consuming vegetable amaranth would bring high health risk. Therefore, adopting Cd-PSC strategy would help reducing the risk of Cd pollution in amaranth. In this study, cv. Nan was identified as a Cd-PSC and recommended to be applied production practice.
文摘随着港口国监督(Port State Control简称PSC)检查制度的普遍实施,这项制度所存在的一些问题也凸现出来:PSC受到了外界非技术因素的强烈干预,PSC检查官的自由裁量权过大,PSC检查程序没有很好地执行,PSC制度本身的缺陷,等等。对这些问题进行数据和政策分析,挖掘这些问题的根源,并对PSC检查制度今后的发展方向进行探讨,对PSC制度更好的实施和发展有一定的参考意义。
