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401.
ChangfengYi ZushunXu WarrenT.Ford 《中国颗粒学报》2004,2(5):222-225
Emulsion polymerization of styrene was carried out using dendrimer DAB-dendr-(NH2)64 as seed. The size and size distribution of the emulsion particles were characterized by transmission electron microscopy (TEM) and dynamic light scattering (DLS), and the effects o.f emulsion polymerization conditions on the preparation of emulsion particle were investigated. It has been found that the nanosized dendrimer/polystyrene polymer emulsion particles obtained were in the range of 26~64nm in diameter, and were monodisperse; the size and size distribution of emulsion particles were influenced by the contents of dendrimer DAB-dendr-(NH2)64, emulsifier and initiator, as well as the pH value. 相似文献
402.
Li Siping** Huang Yuying Hu Yuantai Zhong Weifang Huazhong University of Science Technology Wuhan China Doctoral candidate from Zhengzhou University of Technology Zhengzhou China. 《Acta Mechanica Solida Sinica》1997,10(3):212-219
In this paper, the problem of axisymmetric buckling and postbuckling of a circular thin-film delamination bridged by through-thickness fiber tows in 3D composites is presented. An iterativeprocedure based on Taylor's series expansion is used to generate a family of nondimensionalized post-buckling solutions of the above problem by yon Karman's nonlinear plate theory. Attention is fo-cused, herein, on the effects of the bridge force of through-thickness fibers on the buckling and post-buckling behavior of the delamination. It is found that fiber bridge not only increases the ability of re-sisting delamination buckling and postbuckling, but also brings on the jump of the delamination deflec-tion mode during the postbuckling phase. Consequently the behavior of the composite structure with de-lamination is greatly improved, such as increasing the residual strength and prolonging the service life. 相似文献
403.
1. Introduction Titania TiO2 is a polymorphic oxide, inclusive of two common polymorphs: anatase (space group I41/amd, a0=0.37852 nm, c0=0.95139 nm) and rutile (space group P42/mnm, a0=0.45933 nm, c0=0.29592 nm) , both with octahedrally coordinated tetragonal structures. Anatase is a metastable structure and readily transforms to the stable morphic rutile upon heating (Gribb & Banfield, 1997). Because of their wide application in ceramics, catalysis, electronics, sensors and electrodes, they… 相似文献
404.
Recently, cavity optomechanics has become a rapidly developing research field exploring the coupling between the optical field and mechanical oscillation. Cavity optomechanical systems were predicted to exhibit rich and nontrivial effects due to the nonlinear optomechanical interaction. However, most progress during the past years have focused on the linearization of the optomechanical interaction, which ignored the intrinsic nonlinear nature of the optomechanical coupling. Exploring nonlinear optomechanical interaction is of growing interest in both classical and quantum mechanisms, and nonlinear optomechanical interaction has emerged as an important new frontier in cavity optomechanics. It enables many applications ranging from single-photon sources to generation of nonclassical states. Here, we give a brief review of these developments and discuss some of the current challenges in this field. 相似文献
405.
用紫外吸收变温光谱差减法获得化合物的紫外吸收温差光谱(UVSDT)。测量了系列化合物的温差光谱。结果表明,UVSDT具有很强的特征性:n→σ^*电子跃迁的UVSDT单边红移,温差增大峰强度增加、红移增大;n-π^*电子跃迁的UVSDT为正、负两峰、温差增大,正负两峰各自向正、负方向增强;π-π^*电子跃迁的UVSDT为负峰,温差增大,峰强负向增大,峰位不移动。 相似文献
406.
本文以谱线中心位置在整个谱型中所独有的特性和噪声阈值为依据,提出了一种计算机自动获取谱线中心频率及其相对强度的简便算法,并设计了相应的计算机程序。将该方法和程序应用到具有代表性的由十多条CHF3谱线部分重迭组成的可调远红外实验谱图的预分析,结果表明所获取的谱线中心频率和相对强度与人工获取这些参数初值后经拟合得到的准确结果非常一致,验证了该方法和程序的准确性和有效性,表明其有着广泛的应用前景,可作为处理日益骤增的光谱信息的强有力工具。 相似文献
407.
408.
1 IntroductionIll tllis paper, we co1lsid(tr the fOllowillg elliptic prol)leInwllere n is a bOui1ded regular domai1l in RN(N > 3), N > p > 1, aild a: n - R is a Holdercontinuou8 function which chauges 8ign o11 fl so that the open setsandO-- = {z E Ola(z) < 0}are both nonemPty.We use the standard notations. Let II' lI, denote the norm of L'(o) for s21. DenoteW0lP(fl) the comPletion of C7(fl) under the norm IIuIl = llVuIl;, the norm of tlle dual spaceof WJlp(fl) will be denoted by Il… 相似文献
409.
1 IntroductionIn the heat-conduction equationp is the density,c is the specific heat,k is the thermal conductivityLet u = w -- wco be therelative temperature, where woo is the environmental temperature. In many cases, the thermalconductivity k is dependent of the temperature,forrexample, the heat-conduction of electron iuthe plasma body and the radiation heat-conduction in the high temperature,k(u) = uoum--' (m > 1).Assume that p, c are constants, then the equation (1.1) can be written asWe c… 相似文献
410.
蹇明 《数学物理学报(B辑英文版)》2001,21(2):166-170
1 IntroductionLet H dellote a colllplex Hilbert space. Let B(H) be a co1llplex Banach space of all boundedliuear operators on H, alld B(H)*, tl1e co11jugate space of B(H). The real and inlaginary partsrof all operator T on H are denoted by ReT and IlllT, respectively, i.e., ReT = op, I111T =ng. A contraction is a11 operator T E B(H) with 11TI1 5 1, a proper contractioll is al1operator T 6 B(H) witl1 lITlI < 1.We say that f is all operator-val[1ed fullction on the u1lit disc A = {… 相似文献