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61.
A new isospectral problem is firstly presented, then we derive integrable system of soliton hierarchy. Also we obtain new integrable couplings of the eneralized Kaup--Newell soliton equations hierarchy and its Hamiltonian structures by using Tu scheme and the quadratic-form identity. The method can be
generalized to other soliton hierarchy.  相似文献   
62.
焦脱镁叶绿酸-a作为光活化农药的光活化机理研究   总被引:6,自引:0,他引:6  
介绍了焦脱镁叶绿酸-a作为光活化农药的可能性, 利用激光光解时间分辨吸收技术和自旋捕获EPR技术对其光活化机制进行了研究. 研究发现, 焦脱镁叶绿酸-a的光活化反应主要沿II型即单线态氧机制进行. 另外, 还就单线态氧对选定的光敏氧化靶分子(DNA, 亚油酸和L-色氨酸)的作用情况进行了探索.  相似文献   
63.
Finite-difference time-domain (FDTD) method is used to perform three dimension simulations for the optical performance of 1.75 μm pitch pixels of CMOS image sensor. A three dimension pixel model for CMOS image sensor pixels is set up. Micro-lens optimization, dielectric stack height reduction can decrease the optical power loss. A SiN layer with proper thickness can reduce the reflection at the Si–SiO2 interface. A high refractive index lightpipe is proposed to confine the light within the pixel. The simulation results show that the optical efficiency of the optimized 1.75 μm pixel compare to that before optimized is promoted by more than 10% and the cross-talk is reduced by 50%.  相似文献   
64.
We present a theoretical study on collective excitation modes associated with plasmon and surface-plasmon oscilla- tions in cylindrical metallic nanowires. Based on a two-subband model, the dynamical dielectric function matrix is derived under the random-phase approximation. An optic-like branch and an acoustic-like branch, which are free of Landau damp- ing, are observed for both plasmon and surface-plasmon modes. Interestingly, for surface-plasmon modes, we find that two branches of the dispersion relation curves converge at a wavevector qz = qrnax beyond which no surface-plasmon mode exists. Moreover, we examine the dependence of these excitation modes on sample parameters such as the radius of the nanowires. It is found that in metallic nanowires realized by state-of-the-art nanotechnology the intra- and inter-subband plasmon and surface-plasmon frequencies are in the terahertz bandwidth. The frequency of the optic-like modes decreases with increasing radius of the nanowires, whereas that of the acoustic-like modes is not sensitive to the variation of the radius. This study is pertinent to the application of metallic nanowires as frequency-tunable terahertz plasmonic devices.  相似文献   
65.
A kind of integrable couplings of soliton equations hierarchy with self-consistent sources associated with sl(4) is presented by Yu. Based on this method, we construct a new integrable couplings of the classical-Boussinesq hierarchy with self-consistent sources by using of loop algebra sl(4). In this paper, we also point out that there exist some errors in Yu's paper and have corrected these errors and set up new formula. The method can be generalized other soliton hierarchy with self-consistent sources.  相似文献   
66.
在兰州放射性束流线(RIBLL)上完成了17F/17O+208Pb的弹性散射微分截面角分布测量. 分析了17F/17O弹性散射产物微分截面的对数(ln(dσ/dθ))随散射角平方(θ2)的依赖关系. 结果表明, 在所测量的角度范围内(6°—20°), 17O的这一依赖关系可以用一条直线很好地拟合, 而17F的这一依赖关系需要两条不同斜率的直线才能拟合. 17F数据拟合中的这种斜率改变可能起因于17F的奇异结构. 对其他实验组数据的分析支持以上的结论, 即在一定的角度范围内, 弱束缚核与稳定核相比, 弹性散射产物微分截面的对数与散射角平方的依赖关系有明显的差异, 这可以作为深入研究“晕核”和“皮核”的一个新探针.  相似文献   
67.
A simple 3M-dimensional loop algebra X is produced, whose commutation operation defined by us is as simple and straightforward as that in the loop algebra A1. It follows that a general scheme for generating multicomponent integrable hierarchy is proposed. By taking advantage of X, a new isospectral problem is established, and then by making use of the Tu scheme the well-known multi-component Levi hierarchy is obtained. Finally, an expanding loop algebra FM of the loop algebra X is presented, based on the FM, the multi-component integrable coupling system of the multi-component Levi hierarchy is worked out. The method in this paper can be applied to other nonlinear evolution equation hierarchies.  相似文献   
68.
A new 3M-dimensional Lie algebra X is constructed firstly. Then, the corresponding loop algebra X is produced, whose commutation operation defined by us is as simple and straightforward as that in the loop algebra A1.It follows that a generalscheme for generating multi-component integrable hierarchy is proposed. By taking advantage of X, a new isospectral problem is established, and then well-known multi-component TC hierarchy is obtained. Finally,an expanding loop algebra FM of the loop algebra X is presented. Based on the FM, the multi-component integrable coupling system of the generalized multi-component TC hierarchy has been worked out. The method in this paper can be applied to other nonlinear evolution equations hierarchies. It is easy to find that we can construct any finite-dimensional Lie algebra by this approach.  相似文献   
69.
李铁城  于渌 《中国科学A辑》1978,21(2):150-159
从电流关联函数随时间的变化具有t-3/2渐近行为的假定出发,根据线性响应理论与Kramers-Krnig色散关系,统一地解释了α-LilO3c向弛豫电流按照t1/2衰减,c向介电常数低频下反常增大,并且其实部与虚部相等等一系列异常现象.然后,利用局部平衡假定与线性化Debye—Hückel方程、连续性方程、Poisson方程及Navier-Stokes方程,证明了具有异号载流子的离子电导晶体的电流关联函数确实具有t-3/2渐近行为.  相似文献   
70.
The reaction cross section of 17B on 12C target at (43.7±2.4) MeV/u has been measured at the Radioactive Ion Beam Line in Lanzhou (RIBLL). The root-mean-square matter radius (Rrms) was deduced to be (2.92±0.10) fm, while the Rrms of the core and the valence neutron distribution are 2.28 fm and 5.98 fm respectively. Assuming a "core plus 2n" structure in 17B, the mixed configuration of (2s1/2) and (1d5/2) of the valence neutrons is studied and the s-wave spectroscopic factor is found to be (80±21)%.  相似文献   
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