含砂雾封层在桥面铺装工程中的应用

结合含砂雾封层在国道205桥面铺装上的应用,深入分析了含砂雾封层的防水、防老化作用机理,本文系统总结了国道205桥面雾封层施工质量的控制要点,并对施工前后封层各项性能指标进行跟踪检测,分析结果表明采取含砂雾封层措施确实能对桥面早期微裂缝进行有效封水,延缓桥面病害的发生,延长沥青路面的使用寿命。     

利用SRTM数据修测高山区地貌的探讨

在高海拔区域测制地形图,如青藏高原地区,所获取的遥感影像局部存在着大范围的高山阴影或云雪覆盖,造成立体观测地貌困难的现象,探讨应用SRTM数据对这类特殊区域地貌进行修测补绘。介绍了数据处理的作业过程,并对实验区SRTM与SPOT5影像立体测图成果进行实验对比分析,成果符合要求。     

Optimal investment problem for an insurer and a reinsurer

This paper studies the optimal investment problem for an insurer and a reinsurer. The basic claim process is assumed to follow a Brownian motion with drift and the insurer can purchase proportional reinsurance from the reinsurer. The insurer and the reinsurer are allowed to invest in a risk-free asset and a risky asset. Moreover, the authors consider the correlation between the claim process and the price process of the risky asset. The authors ?rst study the optimization problem of maximizing the expected exponential utility of terminal wealth for the insurer. Then with the optimal reinsurance strategy chosen by the insurer, the authors consider two optimization problems for the reinsurer: The problem of maximizing the expected exponential utility of terminal wealth and the problem of minimizing the ruin probability. By solving the corresponding Hamilton-Jacobi-Bellman equations, the authors derive the optimal reinsurance and investment strategies, explicitly. Finally, the authors illustrate the equality of the reinsurer's optimal investment strategies under the two cases.     

基于JAVA建立树形结构的算法优化

树形结构在程序设计过程具有非常重要的作用,但树形结构的构建相对比较复杂。通过研究设计并实现一种从普通Java对象中建立树形结构的优化算法。     

迹为整数的3×3阶正交矩阵的谱

讨论了3×3阶正交矩阵的特征值和迹的关系,证明了迹为整数的3×3阶正交矩阵的谱可由迹确定,为应用广泛的3×3阶正交矩阵的谱的计算提供了简单实用的方法.     

Synthesis and Largely Enhanced Nonlinear Refraction of Au@Cu_2O Core-Shell Nanorods

Au@Cu_2O core-shell nanorods with tunable thickness of Cu_2O shell were synthesized and their linear and nonlinear optical responses were investigated. Two transverse plasmon resonance peaks were observed when the Au nanorods were coated with Cu_2O shells, which were adjusted by the Cu_2O shell thickness. The nonlinear absorption of the Au@Cu_2O nanorods is enhanced by 5 times at the longitudinal plasmon resonance wavelength compared with that of bare Au nanorods. More intriguingly, largely enhanced nonlinear refraction and suppressed nonlinear absorption at the transverse plasmon resonance wavelength were observed in the Au@Cu_2O nanorods. Our findings indicate the existence of strong local field enhancement at the interface between the Au core and the Cu_2O shell, which would provide a promising strategy in designing plasmonic nonlinear nanodevices with good nonlinear figures of merit.     

基于随机机器故障的柔性作业车间动态调度

为了有效快速地应对生产过程中出现的随机机器故障,构建了一个故障机器可恢复的动态柔性作业车间调度模型,采用事件和周期混合驱动的方式,设计了一个组合重调度策略.在组合重调度策略中,将改进的二叉树右移重调度与完全重调度进行组合,引入序位偏差和完工时间偏差为重调度评价指标,对重调度方法进行选择,并且在精英选择遗传算法(elite selection genetic algo-rithm,ESGA)基础上,对精英选择策略进行改进,以防止陷入局部最优.试验算例仿真结果表明,动态调度算法对随机机器故障下的柔性作业车间动态调度是有效的.     

Effects of Strain Rate,Temperature and Grain Size on the Mechanical Properties and Microstructure Evolutions of Polycrystalline Nickel Nanowires: A Molecular Dynamics Simulation

Through molecular dynamics(MD)simulation,the dependencies of temperature,grain size and strain rate on the mechanical properties were studied.The simulation results demonstrated that the strain rate from 0.05 to 2 ns~(–1 )affected the Young’s modulus of nickel nanowires slightly,whereas the yield stress increased.The Young’s modulus decreased approximately linearly;however,the yield stress firstly increased and subsequently dropped as the temperature increased.The Young’s modulus and yield stress increased as the mean grain size increased from 2.66 to6.72 nm.Moreover,certain efforts have been made in the microstructure evolution with mechanical properties association under uniaxial tension.Certain phenomena such as the formation of twin structures,which were found in nanowires with larger grain size at higher strain rate and lower temperature,as well as the movement of grain boundaries and dislocation,were detected and discussed in detail.The results demonstrated that the plastic deformation was mainly accommodated by the motion of grain boundaries for smaller grain size.However,for larger grain size,the formations of stacking faults and twins were the main mechanisms of plastic deformation in the polycrystalline nickel nanowire.     

用于有机磷农药及其水解产物可视化检测的荧光探针制备及性质研究

使用氯金酸和柠檬酸三钠回流法合成出荧光吸收峰在520 nm的金纳米颗粒,并与罗丹明B修饰合成探针.金纳米颗粒与罗丹明B发生荧光共振能量转移(FRET)作用使罗丹明B的荧光淬灭.在加入毒死蜱之后,毒死蜱及其水解产物能有效取代罗丹明B,使荧光恢复.金纳米颗粒探针对毒死蜱及其水解产物的浓度响应区间为(0～0.1)mm,低至0.1 nm也有响应,且荧光变化迅速,从而能够快速有效地检测超痕量有机磷农药毒死蜱及其水解产物.     

火焰原子吸收分光光度法测定地表水中铜含量的不确定度评定

根据GB 7475—87《水质铜、锌、铅、镉的测定火焰原子吸收分光光度法》建立地表水样测定的数学模型,并根据JJF 1059.1—2012《测量不确定度评定与表示》的要求,计算测量过程中的不确定度分量,最终得出扩展不确定度.经检测计算,该地表水样品中的铜含量为1.53 mg/L,其扩展不确定度为0.036 mg/L,包含因子k=2,地表水样品中铜含量的测量结果应报告为(1.53±0.036) mg/L, k=2.结果表明,火焰原子吸收分光光度法测定地表水样中铜含量的不确定度主要来源于标准曲线拟合、标准溶液配制和样品重复测量.