On the profile of the changing sign mountain pass solutions for an elliptic problem

We consider nonlinear elliptic equations with small diffusion and Dirichlet boundary conditions. We construct changing sign solutions with peaks close to the boundary and consider the location of the peak.

     

疲劳剩余强度的可靠性研究

利用断裂力学，疲劳和可靠性分析方法，对疲劳过程中的剩余强度进行了研究，．通过七组试样的试验，得到了发动机连杆材料１８ＣｒＮｉＷＡ钢的Ｐ Ｒ Ｓ Ｎ曲线（即失效概率 剩余强度 疲劳应力 循环寿命曲线）．本文的分析方法对其他承受疲劳载荷的零部件和材料，具有重要的推广应用价值．     

Positive soliton solutions for generalized quasilinear Schrödinger equations with critical growth

This paper is concerned with the positive solutions for generalized quasilinear Schrödinger equations in R^N${\mathbb{R}}^N$ with critical growth which have appeared from plasma physics, as well as high-power ultrashort laser in matter. By using a change of variables and variational argument, we obtain the existence of positive solutions for the given problem.     

Asymmetric Synthesis of Aminophosphonic Acids and Trifluoromethylated Derivatives Thereof

Various approaches leading to chiral aminophosphonic acids were described. Catalytic asymmetric-induced addition of dialkylphosphite to chiral aldimine gives low ee. value. The diastereoselective alkylation of bicyclic phosphonamide derived from anilinomethylpyrrolidine and followed by subsequent reactions provide much better results. 1,3-Proton Schiff reaction was applied successfully for chiral trifluoromethylated f - and/or g -aminophosphonic acids.     

2D NMR与分子力学计算研究带RF长链麦芽糖的溶液构象

本文研究带R_F长链的麦芽糖在DMSO中的溶液构象。从一系列NOESY谱算得8对H-H之间的距离。分子力学计算中,根据能量最低原则,算得φ_OC1'OC4角为89.4°,中φ_OC6C5O(及φ_OC6'C5'O角)角为-177.2°时的构象最为稳定,从这一稳定构象读得的相应8对H-H间的距离与NOESY的结果符合。     

色散、群速与群折射率

本文讨论了群折射率存在的物理意义,指出群折射率不仅包含了折射率概念而且还体现了折射率的色散性质,同样能作为材料本身的光学性质参量.接着指出在折射率的白光干涉法测量中存在着忽视色散作用而导致的将群折射率误认为折射率的情况.将群折射率与折射率区别开来,不仅可以消除折射率测量中所存在的错误,而且可以突出色散现象在光传播时间特性上的意义.为此建立了折射率与群折射率的相互变换关系,通过对于典型物质的折射率与群折射率变换关系的计算,说明二者在数值上的差别甚至对于气体介质来说也是不能忽略的.     

基于神经网络的反射式表面粗糙度光纤传感器

本文提出了一种新型表面粗糙度光纤传感器,阐述了它的结构、工作原理,给出了测 试结果。利用神经网络很强的输入-输出映射能力,将实验数据交给神经网络处理,减小了测量误差,提高了测量精度,扩大了测量范围。本系统能准确地识别Ra分别为0.012μm, 0.025μm,0.5μm,0.1μm的被测表面。     

紫激光辐射人肺组织的光学特性

应用光纤探测系统和自行研制的光纤探针深度针,成功实现了Ｋｒ＾＋紫激光辐射新鲜离体人肺组织体表面漫反射率和内部光能流率分布的精确测定,并利用漫射理论和加倍（ＡｄｄｉｎｇＤｏｕｂｌｉｎｇ）方法的部分结论,获得了紫光从肺癌组织和正常组织的主要光学特性参数,与蒙特卡罗法拟合实验的光分布曲线得出的结果一致秋临床实际应用提供了重要的原始参数。