Bistable Behaviour of N Two-Level Atoms Interacting with the Field inside a High-Q Cavity Containing a Nonlinear Kerr-Like Medium

Taking the intensity-dependent coupling between atoms and cavity mode into account, we investigate a system consisting of N homogeneously broadened two-level atoms interacting with the field inside a single-mode Fabry- Perot cavity containing a nonlinear Kerr-like medium. We derive the steady-state bistable behaviour of the system, and further analyse in details the influence of several critical parameters on the bistable behaviour.     

混合曲率曲面变形方程的Tricomi问题——Ⅱ.解的存在性

本文在很弱的条件下,证明对混合曲率曲面无穷小变形方程的Tricomi问题,存在L₂弱解和H₁强解。     

Ca+-Pyridine络合物的光解反应

使用反射式飞行时间质谱仪,得到 Ca~ -pyridine 络合物在412～ 690nm 的光解谱.从谱图可见,反应有两个通道,一个是 Ca~ 与 pyridine 分子解离开的非反应淬灭过程,这个通道在所有波段都有,且占优势；生成产物 Ca~ NH_2的通道不仅所占比例小,且在530～590nm 波段关闭. 作为激光波长函数的 Action spectrum 显示出明显的峰,对应于络合物的跃迁.反应的分支比也支持了光解谱图的结论.     

腺嘌呤及其β-环糊精包结物的光谱研究

通过紫外光谱的摩尔比法确定了腺嘌呤与β-环糊精（β－CD）包结物的包结比为1：1，通过紫外光谱和荧光光谱研究了腺嘌呤在酸性，中性，及碱性条件下的光谱变化及与β－CD包结物的光谱变化，分别求得了它们与β－CD包结的平衡常数。     

一类非经典扩散方程整体解的存在唯一性及长时间行为

本文讨论非经典扩散方程第一初边值问题整体解的存在唯一性及长时间行为，建立了一系列新的结果，较好地改进许多已有的结论．     

ASYMPTOTIC BEHAVIOR OF SOLUTIONS OF NONLINEAR NEUTRAL DIFFERENTIAL EQUATION

The boundedness of the every solution and the asymptotic behavior of all solutions of the nonlinear neutral delay differential equation [x(t) - P(t)x(t - t)]' Q1 (t)f(x{t-σ1))-Q2(t)f(x(t -σ2))=0,t≥t0 are investigated, whereτ,σ1,σ2∈(0,∞), P∈C([t0,∞),R), and Q1,Q2∈C([t0,∞),R), f∈C(R,R). The sufficient conditions obtained improve the existing results in the literatures.     

激光散斑法对预制缺口岩石的缝端微裂区变形过程研究

本文应用激光散斑法对预制缺口岩石的缝端微裂区进行了无接触位移测量,求得加裁点位移 d 和缝端张开位移η.通过对主裂缝的跟踪量测,表明该试件的裂缝在失稳前存在着亚临界扩展.在此阶段,预制裂缝缝端主裂缝的形式推测主要是类似“啮合”裂缝及部分张开裂缝,当缝端张开位移达到临界值时,荷载稍增,裂缝即快速扩展,以致发生断裂.     

二元光学波面变形器件的研究

基于计算全息原理设计了二元光学波面变形器件，一块二元光学器件的衍射效率比计算全息可提高４倍，高斯波面整形需要二块整形光学器件，二元光学器件的激光利用率比计算全息提高１６倍，而且制做工艺简单．     

Damage and fracture evaluation of granular composite materials by digital image correlation method

This paper presents the applications of digital image correlation technique to the mesoscopic damage and fracture study of some granular based composite materials including steelfiber reinforced concrete, sandstone and crystal-polymer composite. The deformation fields of the composite materials resulted from stress localization were obtained by the correlation computation of the surface images with loading steps and thus the related damage prediction and fracture parameters were evaluated. The correlation searching could be performed either directly based on the gray levels of the digital images or from the wavelet transform (WT) coefficients of the transform spectrum. The latter was developed by the authors and showed higher resolution and sensitivity to the singularity detection. Because the displacement components came from the rough surfaces of the composite materials without any coats of gratings or fringes of optical interferometry, both surface profiles and the deformation fields of the composites were visualized which was helpful to compare each other to analyze the damage of those heterogeneous materials. The project supported by the National Natural Science Foundation of China (10125211 and 10072002), the Scientific Committee of Yunnan Province for the Program of Steel Fiber Reinforced Concrete, and the Institute of Chemical Materials, CAEP at Mianyang