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991.
通过运用四阶段DEA的方法,首先分析环境变量对各地区技术效率的影响,并得到过滤掉环境因素影响的技术效率;再运用Bootstrap技术,得到各地区纠偏后的技术效率.结果分析表明:可节约劳动的调整对东中部地区效率变动产生较大的影响,资本调整仅起次要作用;可节约资本与劳动的调整对西部地区效率变动都产生重要影响.环境变量的作用表现为:民营资本、基础设施、产业升级、FDI等因素对提升地区技术效率起重要作用. 相似文献
992.
Yurong Jiang Ruiping Qing Haigang Yang Chen Chen Heng Ma Fanggao Chang 《Applied Physics A: Materials Science & Processing》2013,113(1):13-17
The Si nanowire array (SiNWA) was achieved by metal-assisted etching. The effect of alkali-treating of SiNWA on the photovoltaic performance of solar cells was investigated. We found that the post-chemical treatment of SiNWA on solar cells could reduce (i) the surface reflection and (ii) the thickness of “dead layer” so that the short-wavelength spectral response is enhanced. As a result, a solar-spectrum-averaged reflectance of less than 3 % has been reached, a 3-fold enhancement on the spectral response of post-treated SiNWA cell at the wavelength of 400 nm has been observed, together resulting in a remarkable improvement of 45 % in the conversion efficiency. 相似文献
993.
Muthiah Manoharan Akin Akinc Rajendra K. Pandey June Qin Philipp Hadwiger Matthias John Kathy Mills Klaus Charisse Martin A. Maier Lubomir Nechev Emily M. Greene Pradeep S. Pallan Eriks Rozners Kallanthottathil G. Rajeev Martin Egli 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2011,123(10):2332-2336
994.
Biomimetic Surface Engineering of Lanthanide‐Doped Upconversion Nanoparticles as Versatile Bioprobes
995.
996.
Yue‐Hu Wang Qian‐Yun Sun Fu‐Mei Yang Chun‐Lin Long Fu‐Wei Zhao Gui‐Hua Tang Hong‐Mei Niu Huan Wang Qiao‐Qin Huang Jin‐Jin Xu Li‐Juan Ma 《Helvetica chimica acta》2010,93(12):2467-2477
Ten new phenolic compounds including the six neolignans 1 – 3 and 6 – 8 and four caffeoyl derivatives, i.e., myo‐inositol 1‐caffeate ( 9 ), myo‐inositol 6‐caffeate ( 10 ), myo‐inositol 5‐caffeate ( 11 ), and paucine 3′‐β‐D ‐glucopyranoside ( 12 ) were isolated from the whole plants of Selaginella moellendorffii (caffeic acid=3‐(3,4‐dihydroxyphenyl)prop‐2‐enoic acid). Their structures were established by spectroscopic and chemical methods. 相似文献
997.
Chiral C2-symmetric N-heterocyclic carbene (NHC) palladium diaquo complexes 5a–c and the chiral C2-symmetric NHC-palladium complexes 5d and 5e prepared from (R)-BINAM or H8-(R)-BINAM could be used as the catalysts for the enantioselective arylation of arylaldehydes with arylboronic acids in which NHC-Pd complex 5a was found to be fairly effective in this reaction to give the corresponding adducts in moderate enantioselectivities along with moderate to good yields. 相似文献
998.
999.
1000.
Xuesong Shen Meihua Jin Chunxia Zhao Xinqiang Tan Hanfu Liu Xuelian Qin Zhuangpingi Qiu Yi Liu 《Journal of Thermal Analysis and Calorimetry》2013,111(3):1947-1952
In this study, the metabolic thermogenic curves of mitochondria isolated from rat liver tissue were drawn, and the effects of artesunate on metabolic activity of mitochondria were studied using TAM Air Isothermal Microcalorimeter. After isolation from the rat liver, mitochondria still have metabolic activity and can live for a week with appropriate nutrients. With the addition of artesunate (7.5 μM/mL), the metabolic activity of mitochondria was completely lost at this concentration. From the thermogenic curves, we obtained the thermokinetic equations under different conditions: T max = 2512.24 + 1761.53c, R = 0.9375; and Tlag (min) = 707.26 + 285.17c, R = 0.9846. The results showed that artesunate was a mitochondria-targeted drug having obvious effects on mitochondrial metabolism. 相似文献