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991.
It is well‐known that homogeneous electric fields can be used to generate giant unilamellar vesicles (GUVs). Herein we report an interesting phenomenon of formation of GUVs and lipid tubes simultaneously using a nonhomogeneous electric field generated by point‐to‐plane electrodes. The underlying mechanism was analyzed using finite element analysis. The two forces play main roles, that is, the pulling force (F) to drag GUVs into lipid tubes induced by fluid flow, and the critical force (Fc) to prevent GUVs from deforming into lipid tubes induced by electric fields. In the center area underneath the needle electrode, the GUVs were found because F is less than Fc in that region, whereas in the edge area the lipid tubes were obtained because F is larger than Fc. The diffusion coefficient of lipid in the tubes was found to be 4.45 μm2 s?1 using a fluorescence recovery after photobleaching (FRAP) technique. The method demonstrated here is superior to conventional GUV or lipid tube fabrication methods, and has great potential in cell mimic or hollow material fabrication using GUVs and tubes as templates.  相似文献   
992.
Chromium complexes supported by tetradentate dianionic imine‐thioether‐bridged bis(phenol) ligands were prepared and employed in the synthesis of poly(cyclohexene carbonate) via the copolymerization of CO2 and cyclohexene oxide. The catalytic activity, product selectivity, and kinetic behaviors of these [ONSO]CrIII complexes have been systematically investigated. Results indicate the presence of electron‐withdrawing substituents on the ligands to enhance catalytic activity and polymer selectivity. A turnover frequency of 100 h?1 is observed at a temperature of 110 °C, producing polycarbonate with >60% selectivity. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 1938–1944  相似文献   
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ZnO–SnO2 branch–stem nanostructures were realized on a basis of a two-step process. In step 1, SnO2-stem nanowires were synthesized. In step 2, ZnO-branch nanowires were successfully grown on the SnO2-stem nanowires through a simple evaporation technique. We have pre-deposited thin Au layers on the surface of SnO2 nanowire stems and subsequently evaporated Zn powders on the nanowires. The ZnO branches, which sprouted from the SnO2 stems, had diameters in a range of 30–35 nm. As-synthesized branches were of single crystalline hexagonal ZnO structures. Since the branch tips were comprised of Au-containing nanoparticles, the Au-catalyzed vapor–liquid–solid growth mechanism was more likely to control the growth process of the ZnO branches. To test a potential use of ZnO–SnO2 branch–stem nanostructures in chemical gas sensors, their sensing performances with respect to NO2 gas were investigated, showing the promising potential in chemical gas sensors.  相似文献   
998.
A new, divergent, efficient, and selective synthesis of furo- and thieno[2,3-d]pyrimidin-4-amine derivatives by microwave irradiation has been developed starting from readily available amines and substituted 2-aminofuran-3-carbonitrile or 2-aminothiophene-3-carbonitrile, which are converted into corresponding formamidines in DMF using benzenesulfonyl chloride.  相似文献   
999.
We derive Debye series expansion (DSE) for infinitely long multilayered cylinders normally incident by shaped beam. Typically the interaction between multilayered cylinders and Gaussian beam is derived in detail, and localized approximation is introduced to calculate the beam shaped coefficients. Finally DSE is employed to the study of rainbow scattering by graded-index polymer optical fiber (GI-POF).  相似文献   
1000.
The number of transmitted signals in practical quantum key distribution (QKD) protocol is always finite. We discuss the security of decoy states QKD protocol with finite resources by considering the statistical fluctuation for the yield and error rate of the quantum state in different sources of pulses (signal sources and decoy sources). The number of exchanged quantum signals vs positive key generation rate is given with experiment results.  相似文献   
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