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81.
Point‐to‐Plane Nonhomogeneous Electric‐Field‐Induced Simultaneous Formation of Giant Unilamellar Vesicles (GUVs) and Lipid Tubes 下载免费PDF全文
Chuntao Zhu Ying Zhang Yinan Wang Qingchuan Li Dr. Wei Mu Prof. Dr. Xiaojun Han 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(9):2906-2909
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
82.
83.
Research on identifying the order of fringe pattern traces using angular scan and zone search method
A method for automatically identifying the order of fringe pattern traces is presented. It uses the simplified Otsu algorithm for obtaining the threshold, the angular scan in the range of 45~ for searching the trace positions, and the zone search technique for identifying different traces. Experimental results show that the proposed method may reliably obtain the order of fringe pattern traces orientating from almost 45° to 90°. 相似文献
84.
Pu Zhou Zilun Chen Xiaolin Wang Xiao Li Zejin Liu Xiaojun Xu Jing Hou Zongfu Jiang 《中国光学快报(英文版)》2008,6(7)
We demonstrate a scalable architecture for coherent combining of pulsed fiber lasers.A new method for generating synchronous pulsed fiber lasers by direct phase modulation is proposed and investigated.It is shown that phase modulated mutually coupled laser array can be a steady synchronous pulsed fiber laser source.The synchronous pulsed fiber lasers are coherently combined with an invariable phase difference of π in adjacent lasers.Neither active phase control nor polarization control is taken in our experiment. 相似文献
85.
Delong Zhang Xiaojun ChenYufang Wang Dengsong ZhuBo Wu Guoxiang Lan 《Journal of Physics and Chemistry of Solids》2002,63(2):345-358
Raman spectra of as-grown and vapor transport equilibration (VTE) treated Er:LiNbO3 crystals, which have different cut orientations (X-cut and Z-cut), different Er-doping levels (Er:(0.2, 0.4 and 2.0 mol%)LiNbO3) and different VTE durations (80, 120, 150 and 180 h), were recorded at room temperature in the wavenumber range 50-1000 cm−1 by using backward scattering geometry. The spectra were attributed on the basis of their spectral features and the previous experimental work and the most recent theoretical progress in lattice dynamics on pure LiNbO3. In comparison with the pure crystal the most remarkable effect of Er-doping on the Raman spectrum is observed for the E(TO9) mode. It does not appear at 610 cm−1 as the pure crystal, but locates at 633 cm−1. In addition, the doping also results in the lowering of the Raman phonon frequency, the broadening of the Raman linewidth and the changes of the relative Raman intensity of some peaks. The VTE treatment results in the narrowing of the linewidth, the recovery of the lowered phonon frequency and the further changes of relative Raman intensity. The narrowing of Raman linewidth indicates that the VTE processing has brought these crystals closer to stoichiometric composition. The VTE treatment has induced the formation of a precipitate ErNbO4 in the high-doped Er(2.0%):LiNbO3 crystals whether X- or Z-cut. For these precipitated crystals, besides above linewidth and phonon frequency features, they also display more significant Raman intensity changes compared with those not precipitated crystals. In addition, a slight mixing between A1(TO) and E(TO) spectra is also observed for these precipitated crystals. Above doping and VTE effects on Raman spectra were quantitatively or qualitatively correlated with the characteristics of the crystal structure and phonon vibrational system. 相似文献
86.
用修正的RELIEF方法测量高速空气流瞬时速度的理论研究 总被引:3,自引:1,他引:2
修正了拉曼激发激光感应电子荧光(RamanExciationpulseLaser-inducedElectronicFluorescence简称RELIEF)方法,以实现对亚音速和超音速空气流多点时速度的测量,测量精度优于2%。 相似文献
87.
本文针对光测仪器的轴系检测提出了一种新的改进方法,该方法采用数字式电子水平仪测量垂直轴系的径向晃动量;并用不等间隔采样点的最小二乘法计算垂直轴系、水平轴系的晃动误差。该方法及计算程序已成功地应用于多项任务的轴系误差测量中。 相似文献
88.
二(三氯甲基)碳酸酯替代光气合成二苯甲酮类化合物 总被引:6,自引:0,他引:6
二(三氯甲基)碳酸酯替代光气合成二苯甲酮类化合物彭孝军,颜英,周卓华(大连理工大学化工学院大连116012)关键词二苯甲酮,二(三氯甲基)碳酸酯,光气二芳甲酮类化合物是重要的精细化工产品,如二苯甲酮为紫外线吸收剂,N,N,N′,N′-四甲基米氏酮、N... 相似文献
89.
The antifungal and antibacterial agent cladobotryal (1) was synthesized by a convergent route from lactone 31 and aldehyde 13, a key step in the elaboration of the pyridinone ring being conversion of a Boc group on nitrogen into a CO(2)SiPr-i(3) group. The simple model compounds 9 and 10, representing the core of cladobotryal and of 5, respectively, were prepared as support studies for making the natural product. 相似文献
90.
Let k be a positive integer with k?2 and let be a family of functions meromorphic on a domain D in , all of whose poles have multiplicity at least 3, and of whose zeros all have multiplicity at least k+1. Let a(z) be a function holomorphic on D, a(z)?0. Suppose that for each , f(k)(z)≠a(z) for z∈D. Then is a normal family on D. 相似文献