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991.
The Schlesinger equations S
(n,m) describe monodromy preserving deformations of order m Fuchsian systems with n + 1 poles. They can be considered as a family of commuting time-dependent Hamiltonian systems on the direct product of n copies of m × m matrix algebras equipped with the standard linear Poisson bracket. In this paper we present a new canonical Hamiltonian formulation
of the general Schlesinger equations S
(n,m) for all n, m and we compute the action of the symmetries of the Schlesinger equations in these coordinates. 相似文献
992.
The stability of regioregular poly(3-hexylthiophene 2,5-diyl) (P3HT) thin films sandwiched between indium tin oxide (ITO)
and aluminium (Al) electrodes have been investigated under normal environmental conditions (25°C and RH∼45–50%). Electrical
and optical properties of ITO/P3HT/Al devices have been studied over a period of 30 days. Mobility μ of the order of 10−4 cm2/V-s has been obtained from the V
2 law in the as-deposited P3HT films. Scanning electron microscopy (SEM) investigations show blistering of Al contacts in devices
with a poly(3,4-ethylenedioxythiophene) (PEDOT) interlayer on application of voltage whereas no blistering is seen in devices
without PEDOT. The results have been explained in terms of trap generation and propagation and the moisture-absorbing nature
of PEDOT.
相似文献
993.
Jin Sun Yihu Song Qiang Zheng Hong Tan Jie Yu Hong Li 《Journal of Polymer Science.Polymer Physics》2007,45(18):2594-2602
The reinforcement and nonlinear viscoelastic behavior have been investigated for silica (SiO2) filled solution‐polymerized styrene butadiene rubber (SSBR). Experimental results reveal that the nonlinear viscoelastic behavior of the filled rubber is similar to that of unfilled SSBR, which is inconsistent with the general concept that this characteristic comes from the breakdown and reformation of the filler network. It is interesting that the curves of either dynamic storage modulus (G′) or loss tangent (tan δ) versus strain amplitude (γ) for the filled rubber can be superposed, respectively, on those for the unfilled one, suggesting that the primary mechanism for the Payne effect is mainly involved in the nature of the entanglement network in rubbery matrix. It is believed there exists a cooperation between the breakdown and reformation of the filler network and the molecular disentanglement, resulting in enhancing the Payne effect and improving the mechanical hysteresis at high strain amplitudes. Moreover, the vertical and the horizontal shift factors for constructing the master curves could be well understood on the basis of the reinforcement factor f(φ) and the strain amplification factor A(φ), respectively. The surface modification of SiO2 causes a decrease in f(φ), which is ascribed to weakeness of the filler–filler interaction and improvement of the filler dispersion. However, the surface nature of SiO2 hardly affects A(φ). © 2007 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 45: 2594‐2602, 2007 相似文献
994.
Alina Constantinescu 《Applications of Mathematics》2007,52(4):321-326
In one if his paper Luo transformed the problem of sum-fuzzy rationality into artificial learning procedure and gave an algorithm
which used the learning rule of perception. This paper extends the Luo method for finding a sum-fuzzy implementation of a
choice function and offers an algorithm based on the artificial learning procedure with fixed fraction. We also present a
concrete example which uses this algorithm. 相似文献
995.
Hong Mao-Chun Huang Zhi-Ying Cao Rong Jiang Fei-Long Liu Han-Qin State Kev Laboratory of Structural Chemistry and Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences Fuzhou Fujian 《结构化学》1993,(5)
<正> [Au13Ag12(μ-Br)1(μ3-Br)2 (Ph3P)10Br2] Br, monoclinic. space group C2/m, a = 36. 496(17). b=16. 878(7), c-=19. 772(9) A , β=99. 87(5)°, V=11998. 9 A3.Z=2. The final R(Rw) is 0. 097(0. 109) for 3779 reflections with I>3σ(I). The structure can he considered as two icosahedral cluster units (AurAg6) sharing one vertex and linked hy six bromine atoms. The Au - Au, Au - Ag. and Ag-Ag distances fall in the ranges of 2. 69-2. 96. 2. 84-3. 02. and 2. 92-3. 26 A, respectively. 相似文献
996.
PECVDSiON薄膜的工艺控制,性质及其潜在应用 总被引:2,自引:1,他引:1
研究了等离子增强化学气相淀积氮氧化硅薄膜的工艺控制、性质以及薄膜波导在超大规模集成电路光互连中的潜在应用。 相似文献
997.
聚合物分散液晶光栅的衍射特性的研究 总被引:9,自引:4,他引:5
报道了一种由聚合物分散液晶膜与具有周期性条状电极结构板结合的新型光栅器件,借助于聚合物分散液晶膜的电光特性,这种栅对入射光的散射或衍射取决于对其施加的电压,即它是电场可调的,实验结果显示出当驱动电压超过器件器件阈值电压时,衍射光的强度和衍射斑的可见级次被电场调制,而且它能入射光的线性偏振态变为椭圆偏振态。 相似文献
998.
本文对Brauer第24问题[1]作了推广.利用Dade关于循环块的理论得到如下结果:设G是有限群,P是G的循环Sylowp子群.设|P|=pa,a为正整数.令Pi为P中唯一的pi阶子群,1ia.则|Cl(G)|=|Cl(NG(Pi))|的充分必要条件为PiG. 相似文献
999.
本文讨论了在区域提纯过程中,研究液态金属流的表面张力时提出的一个带有非负参数Q的两点边值问题.利用上、下解方法和Schauder不动点定理,证明了当0Q851时,该问题至少有一个解,对已有结果0Q<1进行了重要的改进. 相似文献
1000.
注入控制铜蒸气激光方向性时间过程测量 总被引:1,自引:0,他引:1
实验研究了注入控制对铜蒸气激光非稳腔输出光束质量的影响,从输出光发散角时间分辨过程的测量结果说明注入加速被注入腔内激光发散角的减小过程。由于被注入腔内放大自发辐射的存在,为得到较好的注入控制效果,注入光的脉宽和进入被注入腔的延时必须恰当。 相似文献