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41.
Wei Y Guo X Shuang S Dong C Sun X Wong M 《Journal of photochemistry and photobiology. B, Biology》2005,81(3):190-194
Novel dimeric capsules are generated from the noncovalent assembly of 5, 10, 15, 20-tetrakis(4-N-ethylpyridiniurmyl)prophyrin (TEPyP) and tetracarboxyl-phenyl calix[4]arene. The self-assembly system was investigated based on UV-Vis absorption and fluorescent spectra. The factors affecting the interaction process including pH and concentration were examined in detail. The association constants between TEPyP and calix[4]arene were determined by the nonlinear least squares fit. The results showed that the basic medium is favourable to the interaction and electrostatic interaction was determinate in the processes of self-assembly process. The related mechanism was discussed. 相似文献
42.
自动化样品预处理的一项新技术——吉尔森ASTED系统及其应用(续完)陈小华(华运有限公司香港上环永乐街172—176号永富商业大厦三楼)3应用吉尔森ASTED系统已经被广泛地应用在许多领域,如药理学、药物动力学、药物-蛋白质结合研究、毒理学、临床医学... 相似文献
43.
Fang X Li B Petersen E Ji Y Sokolov JC Rafailovich MH 《The journal of physical chemistry. B》2005,109(43):20554-20557
In this paper, we discuss the factors affecting drop evaporation. We found that the droplet morphology at a specific temperature was controlled by the physical properties of the liquid itself, such as the molecular weight, density, diffusion coefficient in air, and heat of vaporization. Two processes are included in drop evaporation: diffusion of liquid molecules into the air (diffusion part) and flow of the liquid molecules from inside the drop to the free outer shell liquid layer within the liquid-vapor interface (evaporation part). The diffusion part remained steady during drying and was not sensitive to the variation of temperature. The evaporation part, however, was an active factor and determined the differences in drop evaporation behaviors. 相似文献
44.
A catalytic asymmetric conjugate addition/Schmidt-type rearrangement of vinyl azides and (E)-alkenyloxindoles was realized. It afforded a variety of optically active 3,2′-pyrrolinyl spirooxindoles with high yields (up to 98%), and excellent diastereo- and enantioselectivities (up to 98% ee, >19 : 1 dr), even at the gram-scale in the presence of a chiral N,N′-dioxide–nickel(ii) complex. In addition, a possible catalytic cycle and transition state model were proposed to rationalize the stereoselectivity.Lewis acid catalyzed asymmetric synthesis of 3,2′-pyrrolinyl spirooxindole skeletons via conjugate addition/Schmidt-type rearrangement of vinyl azides and (E)-alkenyloxindoles. 相似文献
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Wei Qinghua Li Zi Yang Xi Chen Jianghui Liu Xiaohua Hu Wenhao Liu Shunying 《Molecular diversity》2019,23(4):997-1010
Molecular Diversity - A Rh(I)/Sc(III) co-catalyzed synthesis of highly valuable functionalized 1,4-diketone derivatives in good yields and with an excellent diastereoselectivity. The established... 相似文献
47.
Yunxi Shi Yixi Cai Xiaohua Li Hui Xu Weijun Li Xiaoyu Pu 《Plasma Chemistry and Plasma Processing》2016,36(3):783-797
An experimental study of the regeneration of diesel particulate filter (DPF) was conducted through the use of a self-designed Non-thermal plasma (NTP) injection system with an experimental temperature of 20–300 °C, with atmospheric air being used as the gas source. The results revealed that the PM could be broken down into CO and CO2 by NTP, through a discharge reaction of the NTP reactor. As the temperature increases, the mass of C1 (mass of C in CO) showed an overall declining trend. Interestingly, the mass of C2 (mass of C in CO2) and C12 (the sum of C1 and C2) both showed an initial increase, followed by a decrease. The peak mass of C12 appears at 150 °C, and both axial and radial temperature gradients are less than the limit of DPF temperature gradient at this temperature. In conclusion, DPF can be regenerated by the NTP technology at a lower temperature, which can aid in the avoidance of thermal damage of DPF. The technology boasts a great advantage in adopting atmospheric air as its gas source, which can not only reduce costs, but also is convenient. 相似文献
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