弹性梁式薄板在横向绕流中的大变形

采用相容拉格朗日-欧拉(ULE)法,给出了弹性薄板理想流体横向绕流条件下变形与应力的理论算法,其中:对固体采用拉格朗日法;对流体采用欧拉法;对相互接触面采用拉格朗日法和欧拉法.建立了不问断横向绕流条件下弹性梁式薄板的大弯曲变形的非线性微分方程.求解该方程时,将纵向位移分量和曲率的改变量用挠度表示.通过具体算例分析了各参数对悬臂梁式薄板挠度、纵向位移及应力大小的影响.理论解与数值解进行比较,验证了理论解的可靠性.     

Exciton emissions of CdS nanowire array fabricated on Cd foil by the solvothermal method

Nanowires have recently attracted more attention because of their low-dimensional structure, tunable optical and electrical properties for next-generation nanoscale optoelectronic devices. Cd S nanowire array, which is(002)-orientation growth and approximately perpendicular to Cd foil substrate, has been fabricated by the solvothermal method. In the temperature-dependent photoluminescence, from short wavelength to long wavelength, four peaks can be ascribed to the emissions from the bandgap, the transition from the holes being bound to the donors or the electrons being bound to the acceptors, the transition from Cd interstitials to Cd vacancies, and the transition from S vacancies to the valence band,respectively. In the photoluminescence of 10 K, the emission originated from the bandgap appears in the form of multiple peaks. Two stronger peaks and five weaker peaks can be observed. The energy differences of the adjacent peaks are close to 38 me V, which is ascribed to the LO phonon energy of Cd S. For the multiple peaks of bandgap emission, from low energy to high energy, the first, second, and third peaks are contributed to the third-order, second-order, and first-order phonon replica of the free exciton A, respectively;the fourth peak is originated from the free exciton A;the fifth peak is contributed to the first-order phonon replica of the excitons bound to neutral donors;the sixth and seventh peaks are originated from the excitons bound to neutral donors and the light polarization parallel to the c axis of hexagonal Cd S, respectively.     

Signorini接触问题的边界变分不等式

本以Signorini接触问题为背景，讨论了变分不等式与边值问题的等价性，利用Green公式，基本解和基本解法向导数的性质，将区域型变分不等式化成等价的边界型变分不等式，并证明了边界变分不等式解的存在唯一性，为使用边界元方法数值求解提供理论依据。     

大分子二苯甲酮光引发剂的合成及性能研究

合成了两种大分子光引发剂PPI 1和PPI 2,紫外吸收行为均与4-BP相似,摩尔消光系数比4-BP高,且光解速率快。在不加助引发剂EDAB条件下引发单体HDDA聚合效率良好,对比PPI 1和PPI 2,随着吸光基团官能度（分子量）增大,聚合速率增加、最终转化率增高。将各自诱导单体PEGDA聚合的固化膜,在二氯甲烷溶液中浸泡5天后,PPI 1的萃取量是4-BP的44.5%,PPI 2的萃取量是4-BP的40%,说明PPI 1和PPI 2都是引发效率良好的低迁移光引发剂。     

非线性流体弹性力学研究进展

流体弹性力学理论是用来描述液体、气体的运动与弹性结构相互作用的学科.由于其交叉性质, 涉及到人类日常生活中的方方面面,致使在许多学科和工程领域中都成了主要的研究内容,并得到了广泛地应用.本文在阐述研究流体与弹性体相互作用的非线性问题的重要意义及分类方法的基础上,介绍了非线性流体弹性力学的特征、研究现状和非线性问题的研究方法,如理论分析法、实验分析法、数值分析法和半解析法等的进展;介绍了描述介质相互作用的任意拉格朗日-欧拉(ALE)法、相容拉格朗日-欧拉(ULE)法、单一拉格朗日(SL)法和单一欧拉(SE)法之间的关系,并且对这些研究方法的优缺点进行了比较;介绍了非线性流体弹性力学研究的内容和在气动弹性力学、水弹性力学、环境流体弹性力学、微尺度流体弹性力学和涡激振动等领域中的应用;阐述了非线性流体弹性力学的发展前景和所面临的任务.