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991.
992.
2010上海世博会影响力的定量评估——影响力的点刺激连带效应定量评估模型 总被引:2,自引:0,他引:2
利用互联网数据,在合理假设的前提下,给出了上海世博会对上海旅游业影响的定量评估.利用线性加权综合分析法建立综合评价指标的线性模型,并从两个不同的角度,分别得出上海世博会对上海旅游业的综合评价指标,同时建立灰色系统预测模型,利用2006至2009年的评价指标,对2010年的评价指标进行预测.通过实际的增长值与预测增长值的... 相似文献
993.
994.
The particle acceptance instead of the G-factors has been introduced for a particle telescope. The particle acceptance of a telescope module TEST is simulated by using the GEANT4 Monte-Carlo package. The results are presented and explained. 相似文献
995.
Zeng Wu Ming Yan Shi-He Hu Zhi-Cheng Yu Yong Zhu Ya-Dong Cheng Hai-Chun Liu Yan-Min Zhang Si-Hui Yao Wei-Fang Tang Tao Lu 《中国化学快报》2014,25(2):351-354
A series of novel indole derivatives were designed and synthesized and their inhibitory activity against B-Raf and HepG2 cell were also described. Among them, compounds 7a and 7b exhibited excellent potency, which showed the potential for further research as lead compounds. 相似文献
996.
Zai-Gang Luo Yu Zhao Chao Ma Xue-Mei Xu Xiao-Mei Zhang Nian-Yu Huang Hong-Qiu He 《中国化学快报》2014,25(5):737-740
A series of novel calix[4]arene derivatives incorporating two triazolyl 1 3-diketo subunits in alternate positions at the lower rim were synthesized and screened for HⅣ integrase inhibition activity.The chemical structures of these compounds were confirmed by means of1H NMR 13C NMR,and ESI-MS.Preliminary bioassays indicated that calix[4]arene derivatives proved to be more active than p-tertbutylcalix[4]arene derivatives.In particular,compound 4g presented the most potent integrase strand transfer inhibitory activity with an IC50value of 6.1 mmol/L. 相似文献
997.
A convenient one-pot three-component method for the preparation of tetra-substituted thiophene derivatives has been developed. Reaction of acetyl acetone 1, phenyl isothiocynate 2 and 2-chloromethyl derivatives 3a–3c in the presence of potassium carbonate afforded the target compounds, namely ethyl2-(4-acetyl-3-methyl-5-(phenylamino)thiophen-2-yl)-2-oxoacetate derivatives 4a–4e, ethyl 3-(4-acetyl-3-methyl-5-(phenylamino)thiophen-2-yl)-3-oxopropanoate derivatives 4f–4i, di((4-acetyl-3-methyl-5-phenylamino)thiophen-2-yl)ketone derivatives 4j–4n in reasonable overall yields. The synthesized compounds were screened for antimicrobial activity. The detailed synthesis, spectroscopic data and antimicrobial activities of synthesized compounds were reported. 相似文献
998.
Kun Fang Guo-Qiang Dong Hai Gong Na Liu Zhen-Gang Li Shi-Ping Zhu Zhen-Yuan Miao Jian-Zhong Yao Wan-Nian Zhang Chun-Quan Sheng 《中国化学快报》2014,25(7):978-982
A series of novel E-ring modified evodiamine derivatives were designed and synthesized as antitumor agents. Their capacity to interfere with the catalytic activity of topoisomerase Ⅰ and Ⅱ was evaluated by the relaxation assay. In vitro antitumor activity results revealed that compound 12 showed good antitumor activity with a broad spectrum. Its binding modes with topoisomerase Ⅰ and Ⅱ were clarified by molecular docking. 相似文献
999.
1000.
压裂改造已成为姬塬油田最主要的增产措施。压裂液的好坏对压裂增产起着关键作用,常规胍胶压裂液存在着水不溶物和破胶不彻底现象,VES粘弹性表面活性剂耐温性较差,性能不能满足地层温度。本文采用EA-Q缔合聚合物配制成清洁压裂液,室内性能评价结果表明,该压裂液的最佳使用浓度为0.35%~0.45%;清洁压裂液剪切1h后粘度均保持在50mPa·s以上;80℃时静态滤失系数为6.58×10-4m/min-1;静态悬砂沉降速率为0.0069 cm/min;破胶时间2.5 h时破胶液粘度为4.8 mPa·s;岩心伤害率13.0%~15.0%。 相似文献