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991.
992.
Yuru Zou Yuanyuan Yao Wenxia Li 《Journal of Mathematical Analysis and Applications》2008,340(2):1422-1432
Based on a scheme by Lau and Ngai, a sufficient and necessary condition for an IFS of contractive similitudes to satisfy the open set condition is given. A class of Sierpinski carpets with parameters (λ1,λ2) is then investigated. 相似文献
993.
994.
Bangben Yao 《Tetrahedron letters》2008,49(37):5385-5388
In the presence of triflic anhydride, sulfonylation of arenes with sulfonamides proceeded smoothly in Cl2CHCHCl2 at 80-140 °C, which gave rise to the desired products in good to excellent yields. 相似文献
995.
996.
997.
To investigate the effect of photodynamic therapy (PDT) with hematoporphrin monomethyl ether (HMME) on bovine immunodeficiency virus (BIV) can provide the basis theory for photoinactivation of human immunodeficiency virus (HIV). To assess the protection of HMME-PDT on the cell line Cf2Th infected with BIVR29 by 3-(4,5)-dimethylthiahiazol-2-yl-3,5-di-phenytetrazolium bromide (MTT) with power density of 5 and 25 mW/cm2 and energy density from 0.6 to 3 J/cm<'2>. To observe the inhibition of membrane fusion using a new reporter cell line BIVE by fluorescence microscope. HMME-PDT has significant protectant effects on Cf2Th-BIVR29 with both power densities, especially in the group of high power density. Fluorescent microscope shows that there is no significant difference between the group of PDT and control, which means PDT could not inhibit the BIV-mediated membrane fusion. 相似文献
998.
Zhongbing Huang Xiaoming Liao Yunqing Kang Guangfu Yin Yadong Yao 《Journal of colloid and interface science》2009,330(2):399-403
Why is it that drops do not slip down inclined thin fibers or spider silks? The possible explanation is based on the existence of fiber size, which causes a sustaining force that pins these drops. Following this explanation, the drop remains in equilibrium until a critical value of the sustaining force is reached. We suggest an alternative analyses, from the point of view of the inclined fiber at which the drop slips down is predicted. This result does not depend explicitly on silk surface roughness, but only on the drop size and surface tensions. 相似文献
999.
1000.
Dong Han Xiang-Bao Meng Lin-Na Wang Hong Liu Yun Yao Zhuo Wang Zhen-Jun Yang Zhen-Min Liu Zhong-Jun Li 《Tetrahedron: Asymmetry》2009,20(4):399-410
A series of novel alkyl substituted fructose-based oxadiazoles were synthesized and their cytotoxic activities toward tumor cells were investigated. We studied the reaction mechanism and the stereochemistry of the reaction. Tautomerization between isomers 2 and 3 was observed in solution. The tautomerization was accelerated by heating or in the presence of acetic acid. An intermediate 6 during the heterocyclization was isolated, and two different pathways for the heterocyclization were suggested. On the basis of these findings, an efficient method, with the assistance of microwave irradiation was developed for the synthesis of 4 and 5. The yields were satisfactory and no by-products were found. We also proposed that the (R/S)-configurations of oxadiazoles were determined by the E/Z configurations of hydrazones. 相似文献