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51.
氧化铟锡薄膜的二阶非线性光学特性研究   总被引:2,自引:0,他引:2  
利用二次谐波产生技术研究了氧化铟薄膜的非线性光学特性.氧化甸锡薄膜中多晶晶粒的优先取向,使其产生了非常强的二次谐波信号,并且在一定的薄膜存度以上,随薄膜厚度的增加二次谐波信号显著增强.由于多晶晶粒的优先取向使得薄膜基板平面内存在着非常明显的非线性光学各向异性.  相似文献   
52.
Fourier transform infrared spectra in the low frequency region (500–150cm?1) of Langmuir-Blodgett films of chlorophyll a (Chi a), chlorophyll b (Chi b) and pheophytin a have been studied. Correlations between spectral changes in monolayer and multilayers of Chi a and Chi b and their adducts with water and dioxane have been established. Spectroscopic evidence has indicated that, although there are no individual absorption bands that can be assigned to pure Mg-nitrogen and/or Mg-oxygen stretching or bending modes, there are several bands in the400–200 cm?1 region of the spectra containing considerable contributions from metal-nitrogen and metal-oxygen vibrational modes. These specific vibrations exhibit marked intensity changes and shifts upon water and dioxane interaction. The different states of chlorophyll aggregation in Langmuir-Blodgett mono- and multilayers films resulted in noticeable changes in their far-IR spectra.  相似文献   
53.
In this paper, we study a class of coupled fractional nonlinear Schrödinger system with periodic boundary condition. Using Galerkin method, the existence of global smooth solution is obtained. We also prove the uniqueness of the solution.  相似文献   
54.
邓里文  王恭明 《光学学报》1998,18(11):556-1561
测量了棱镜/LB膜/银膜/空气,棱镜/银膜/空气,棱镜/银膜/空气三种结构在衰减全反射条件下激发的表面等离子激元波由于银膜-空气界面粗糙度而散射以空气中的辐射效率,同时,由散射光强分布计算出表面度粗糙度参数随横向相关长度σ和表面波纹深度δ,再由σ和δ计算出理论辐射效率,理论与实验结果相符合。  相似文献   
55.
In this paper, we study the existence of standing waves of the coupled nonlinear Schr dinger equationsThe proofs of which rely on the Lyapunov-Schmidt methods and contraction mapping principle are due to FWeinstein in [1].  相似文献   
56.
Chemical- and photostability of unnatural base pairs (UBPs) are important to maintain the genetic code integrity, and critical for developing healthy semisynthetic organisms. As reported, dTPT3 was less stable upon irradiation, and thus might act as a pervasive photosensitizer to induce oxidative damage within DNA, causing harm to living semi-synthetic organisms when exposed to UVA radiation. However, there was no knowledge about molecular-level understanding of this damage process. In this paper, we not only identified four photoproducts of dTPT3, including desulfur-dTPT3 (dTPT3H), TPT3 sulphinate (TPT3SO2), TPT3 sulphonate (TPT3SO3) and TPT3-thioTPT3 (TPT3STPT3), but also established a Type II photosensitized oxidation mechanism. In addition, the antioxidant (sodium ascorbate) was able to effectively inhibit the photoproducts formation of dTPT3 and dTPT3 in DNA, suggesting that a reductive environment might protect DNA bearing dTPT3 against UVA oxidation and ameliorate its adverse biological effects. The comprehensive understanding of TPT3’ photochemical stability will give researchers helpful guidance to design more photostable UBPs and construct healthier semisynthetic organisms.  相似文献   
57.
证明了右端可测的各项异性椭圆方程基本解的存在性,其中应用了各项异性Sobolev空间和Lebesgue空间.首先得到近似方程的解,然后通过对这些解的子列取极限,得到原方程的解.关键是要有一个近似函数空间以及近似方程的先验估计.最后运用Vitali定理证明了原方程基本解的存在性,推广和改进了已有方程.  相似文献   
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