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171.
Wang Lujie Wen Xiaodong Zhang Xujun Yuan Shuntao Xu Qingbo Fu Feiya Diao Hongyan Liu Xiangdong 《Cellulose (London, England)》2021,28(9):5867-5879
Cellulose - In this article, carboxymethyl chitosan (CMC) and (3-carboxypropyl) trimethylammonium chloride (CPTC) were used as raw materials to prepare an antibacterial cotton fabric with excellent... 相似文献
172.
Congde Huo Chougu SunDongcheng Hu Xiaodong JiaXiaolan Xu Zhongli Liu 《Tetrahedron letters》2011,52(51):7008-7010
The reaction of ethyl diazoacetate with aryl imines can be initiated by persistent cation radical salt tris(4-bromophenyl)aminium hexachloroantimonate, giving exclusively cis-aziridine carboxylates. 相似文献
173.
Xiaodong Jia Chang Qing Congde Huo Fangfang Peng Xicun Wang 《Tetrahedron letters》2012,53(52):7140-7142
A domino process between iminoethyl glyoxylate and N-vinylamides was achieved under the catalytic radical cation salt induced conditions, producing a series of quinoline-2-carboxylates. N-Vinylamides were involved as an acetylene equivalent. A possible mechanism was proposed to rationalize the formation of the products. 相似文献
174.
Hiroshi Yamaguchi Xiaodong Niu Xinrong Zhang Yuta Ito 《ournal of non Newtonian Fluid Mechanics》2010,165(7-8):385-393
An experimental study investigated the effects of glass fiber suspensions on the onset of instability in the non-Newtonian fluid flow in the concentric spherical gaps between an inner rotating hemisphere and an outer stationary whole sphere. Glass fibers with different aspect ratios were mixed with a macromolecule polymeric solution to obtain different suspension fluids. For comparison, the pure macromolecule polymeric fluid was also investigated. The torques on the inner sphere were measured for various spherical gaps and various rotational Reynolds numbers. The onset of instability of the polymeric fluid flows was delayed by adding glass fibers to the polymeric solution for all tested gap ratios. 相似文献
175.
Xiaodong Hou Qiaobo Li Yong He Lin Jia Yang Li Yingdan Zhu Amin Cao 《Journal of Polymer Science.Polymer Physics》2009,47(14):1393-1405
Spontaneous stereocomplex aggregation of diblock poly(styrene)‐b‐poly(L ‐lactide) PS‐b‐PLLA/poly(D ‐lactide) PDLA pairs has been investigated under ambient temperature in tetrahydrofuran solution. First, diblock PS260‐b‐PLLA165 and PS260‐b‐PDLA162 bearing similar lengths of respective PLLA and PDLA blocks were synthesized through controlled atom‐transfer radical polymerization of styrene, and a subsequent living ring‐opening polymerization of optically pure lactides, and their structures were further characterized by nuclear magnetic resonance spectroscopy (NMR) and gel‐permeation chromatography (GPC). Subsequently, new enantiomeric poly(D ‐lactide) stabilized core‐shell fluorescent CdSe quantum dots (CdSe/PDLA QD) were designed and prepared as sensitive fluorescence labels to shed new lights on the spontaneous stereocomplex aggregation in THF, which was mediated by stereocomplexation of the PLLA and PDLA chains. Upon simply mixing two individual THF solution of diblock PS260‐b‐PLLA165 and HO‐PDLA30‐SH, spontaneous stereocomplex aggregation was studied, and the aggregated uniform spherical particles were observed by scanning electronic microscopy (SEM) to exhibit average particle diameters of 2.0 μm. Finally, utilizing the prepared CdSe/PDLA QDs as new fluorescent labels, morphologies of the spontaneous aggregates by new diblock PS260‐b‐PLLA165/HO‐PDLA30‐SH pair were for the first time directly visualized by a confocal laser scanning fluorescence microscopy (CLSFM). These results might suggest alternative ways to simply prepare functional fluorescent particles with tunable diameter sizes and would be helpful to understand the mechanism of stereocomplex particle aggregation. © 2009 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 47: 1393–1405, 2009 相似文献
176.
177.
低杂波波谱的下移和可近性条件 总被引:2,自引:1,他引:1
本文利用改进磁面位移计算的射线轨迹Code,研究在射线轨迹的第圈n的下移以及下移量与各等离子体参量的关系。我们发现等离子体密度越高,波的频度越低,n的下移量越大。计算表明:在射线的第一圈n下移量的最大值大致与n^-e/「f^1.5q(rc)」成正比、也与电流、密度的分布和n的初值等有关。 相似文献
178.
报道了4-甲氧基.2-溴代丁烯内酯(4)与几种醇通过串联的双。Michael加成及分子内的亲核取代反应,简便地得到了环丙烷类化合物8。经元素分析、IR、^1HNMR、^13CNMR和MS对目标产物进行了结构表征,其中8a通过单晶培养和x射线晶体测定,确定了它的立体结构。 相似文献
179.
以Nd∶YAG激光器抽运光学参变振荡器 /光学参变放大器做为激发源 ,得到了NO分子在 2 2 0~ 35 0nm波长范围内的双光子激光诱导荧光光谱 ,并将其归属于A2 Σ(ν′ =0 )→X2 Π(ν″ =1~ 8)跃迁 ,用最小二乘法拟合获得NO分子X2 Π态振动常量″ωe =(190 4 .7± 7.3)cm-1,″ωe ″xe =(14 .2± 1.2 )cm-1,″ωe″ye=- (0 .0 2 18± 0 .0 0 91)cm-1,及平衡位置的力常量k =(1.5 99± 0 .0 12 )× 10 3 N·m-1。计算了所得跃迁谱带的弗兰克康登因子及相对荧光强度 ,结果与实验观测值相符。这可为用激光诱导荧光光谱技术探测大气污染物NO分子提供理论及实验参考 相似文献
180.
在对作者原有工作改进的基础上,应用自行研制的“光纤探针深度计”首次精确测定了Kr+紫激光406.7~415.4um和He-Ne激光632.8nm波长处新鲜离休人肺组织中光能流率分布,获得这两种重要波长处人肺正常组织和人肺腺鳞癌组织中光能流率的分布规律及光穿透深度的数值:(1)δnormal=0.08mm,δtumour=0.32mm(λ=406.7~415.4nm);(2)δnormal=1.19mm,δturmour=1.70mm(λ=632.8nm),并对现有人肺组织的光穿透深度数据作了总结和讨论. 相似文献