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61.
The efficient accumulation of dyes in constructed natural polyelectrolyte microshells under moderate conditions, combined with the photo-assisted Fenton reagent, opens a new route for the effective elimination of dye pollutants from waste water.  相似文献   
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New anti-HIV prodrugs, conjugates of AZT and d4T with boranophosphates, were prepared by the H-phosphonate method. Their structures were determined by negative ion electrospray ionization mass spectrometry (ESI-MS) in conjunction with tandem mass spectrometry (MS/MS). The fragmentation pathways were investigated, and most of the fragment ions contained the boranophosphate or phosphinate group.  相似文献   
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Heavy metal cations Cd2+, Pb2+, and Hg2+ were added to substitute for Ca2+ in culture media to study their effect on the relationship between CaM and the proliferation of cultured rabbit aortic smooth muscle cells (ASMC). It was found that all the heavy metal cations studied stimulated the proliferation of ASMC in varying degrees, increased the CaM content in cells at late G1 stage and decreased the activity of cAMP PDE. These results suggest that the adverse effect of heavy metals may be related to the pathogenesis of atherosclerosis and hypertensive disease.  相似文献   
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The underlying mechanisms of stability, metastability, or instability of the Cassie-Baxter and Wenzel wetting modes and their transitions on superhydrophobic surfaces decorated with periodic micropillars are quantitatively studied in this article. Hydraulic pressure, which may be generated by the water-air interfacial tension of water droplets or external factors such as raining impact, is shown to be a key to understanding these mechanisms. A detailed transition process driven by increasing hydraulic pressure is numerically simulated. The maximum sustainable or critical pressure of the Cassie-Baxter wetting state on a pillarlike microstructural surface is formulated for the first time in a simple, unified, and precise form. This analytic result reveals the fact that reducing the microstructural scales (e.g., the pillars' diameters and spacing) is probably the most efficient measure needed to enlarge the critical pressure significantly. We also introduce a dimensionless parameter, the pillar slenderness ratio, to characterize the stability of either the Cassie-Baxter or the Wenzel wetting state and show that the energy barrier for transitioning from the Cassie-Baxter to the Wenzel wetting mode is proportional to both the slenderness ratio and the area fraction. Thus, the Cassie-Baxter wetting mode may collapse under a hydraulic pressure lower than the critical one if the slenderness ratio is improperly small. This quantitative study explains fairly well some experimental observations of contact angles that can be modeled by neither Wenzel nor Cassie-Baxter contact angles and eventually leads to our proposals for a mixed (or coexisting) wetting mode.  相似文献   
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Angular distributions of elastic and inelastic scattering have been measured for152Sm+12C at 63.2 MeV and148Nd+16O at 90.9 MeV. An evident interference pattern in the inelastic scattering has been observed for the first time in a strong Coulomb coupling system.We are indebted to Dr. S. Pieper for supplying the Ptolemy Program. One of us (Chenglie Jiang) would like to acknowledge the Argonne National Laboratory for the opportunity given, to perform theoretical calculations with the code Ptolemy during his visit there. Thanks are also due to Mr. H. Folger (GSI, Germany) for supplying the targets. This work was supported in part by China National Nature Science Fundation.  相似文献   
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Letf:XX be a selfmap of a compact connected polyhedron, andA a nonempty closed subset ofX. In this paper, we shall deal with the question whether or not there is a mapg:XX homotopic tof such that the fixed point set Fixg ofg equalsA. We introduce a necessary condition for the existence of such a mapg. It is shown that this condition is easy to check, and hence some sufficient conditions are obtained.Partially supported by the Natural Science Foundation of Liaoning University.  相似文献   
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