电场线的三维演示现象的机理研究

本文对电场线的三维演示新方法进行机理分析，为实验提供理论依据。     

Weak aggregating algorithm for the distribution-free perishable inventory problem

We formulate the multiperiod, distribution-free perishable inventory problem as a problem of prediction with expert advice and apply an online learning method (the Weak Aggregating Algorithm) to solve it. We show that the asymptotic average performance of this method is as good as that of any time-dependent stocking rule in a given parametric class.     

正电性胶态纳米银中加入凝聚剂后的表面增强拉曼光谱

在柠檬酸还原制备的正电性胶态纳米银中加入凝聚剂HNO₃和NaNO₃后,用波长为633 nm的激光激发,获得了较强的表面增强拉曼散射光谱(SERS谱),通过讨论及实验明确该SERS谱是来自于还原剂中的柠檬酸根离子,并说明该方法制备的纳米银的吸附层是带正电的银离子,扩散层是带负电的柠檬酸根离子。     

Linear programming with online learning

We propose online decision strategies for time-dependent sequences of linear programs which use no distributional and minimal geometric assumptions about the data. These strategies are obtained through Vovk's aggregating algorithm which combines recommendations from a given strategy pool. We establish an average-performance bound for the resulting solution sequence.     

纳米Co(OH)2/HY复合物的制备及其电化学电容性能

当材料以纳米尺度存在时，某些物理及化学性质将发生根本性变化。因而，纳米技术的概念绝不仅仅是尺寸的缩小，更应体现在物理概念、系统设计、材料合成及制造等方面所发生的根本性革命。随着21世纪的来临，人们正努力地将越来越多的纳米材料功能化，Co(OH)2通常用作Ni(OH）2电池活性材料的添加剂。关于Ni(OH）2的许多电化学性质已有大量报道，而对于Co(OH）2的研究却很少涉及。本文报道了一种新的纳米级Co(OH）2／HY复合物的制备方法，并将制得的复合物制成超级电容器电极，研究了其超电容特性。此外，还初步提出了Co(OH）2各向异性的形貌形成机理。     

Helium behavior and vacancy-defect evolution in nickel-base alloy by helium ion beam irradiation and annealing

Nickel-base alloys have been selected as a potential metallic material for reactor internals in Generation IV reactors. In order to evaluate their helium embrittlement resistance, microstrain changes and evolution of vacancy-type defects after Helium irradiation and postimplantation annealing have been studied by grazing incidence X-ray diffraction (GIXRD) and slow positron doppler broadening spectroscopy (PDB). GIXRD results show that the increase in microstrain after helium irradiation is more pronounced at high doses. The observed S parameters of PDB increase with the irradiation doses, which indicates a significant number of vacancy-type defects, possibly helium-vacancy clusters. For postimplantation annealing specimens, the microstrain characterized by GIXRD has recovered. The surprise is the S parameters that significantly increase, revealing that helium atoms trapped at unstable helium-vacancy clusters desorb during annealing, contributing to the growth of helium bubbles. These findings of microstrain mechanisms and vacancy-type defects behaviors give us new insights into the helium irradiation evaluation.     

稳态时剪应力作用下肢体簇团形成/破裂的机理

胶体簇团形成／破裂过程机理研究一直是胶体研究中一个十分活跃的领域．因为不同的聚团机理导致胶体不同的物理化学性质：粘度、空隙度、导电性甚至光学特性等，因而使其备受注目．当前，实验研究证明了簇团边缘的胶体颗粒和介质有着频繁的交换’‘’，特别是在受到外力的作用下，这种交换会更加激烈．计算机模拟研究证实了簇团和介质间颗粒交换的机理可以是颗粒一颗粒型的，也可以是簇团一簇团型的”、”．所谓颗粒一颗粒型机理是指（接近或完全）由单个颗粒互相结合，或单个颗粒被结合进大的簇团．在结合期间，被结合的颗粒可以在簇团边缘…     

稳态时剪应力作用下胶体簇团形成/破裂的机理

Population correlation function P(t) has been used to examine the mechanism of breakage and coalescence of clusters at steady-state under shear, the results are in qualitative agreement with experiments. The research indicates that with a weak potential the mechanism of breakage and coalescence of clusters at steady-state under shear is predominately controlled by the particle-particle model, but that with a strong potential the mechanism shifts to that of cluster-cluster for large clusters; for small clusters, however, the mechanism of particle-particle model seems still to remain predominate, further work needs to be done.     

Fe3+-TiO2/SiO2薄膜催化剂的结构对其光催化性能影响

以硅胶为载体,采用溶胶-凝胶法制备了掺杂不同量Fe3+的TiO2光催化剂(Fe3+-TiO2/SiO2),以氙灯为光源,罗丹明B为目标降解物,对其光催化活性进行了研究.结果表明,Fe3+-TiO2/SiO2比TiO2纳米粉有更好的催化活性,Fe3+的最佳掺入量为0.03％.罗丹明B在粉体和膜催化剂的作用下遵循不同的光催化反应机理.根据XRD,SEM,Raman,XPS和FTIR的表征结果可认为,TiO2在SIO2表面薄膜化和Ti-O-Si键的形成是催化活性提高和降解机理不同的主要原因.     

西南某水电站谷底深厚覆盖层与卸荷松弛带特征及其成因机制分析

钻孔揭示,该水电站河谷谷底发育着深厚覆盖层及卸荷松弛带。深厚覆盖层纵向上可以分为3层:下部和上部为正常的河流相,中部为多成因堆积物加积层;谷底浅表部岩体结构松弛,完整性差,裂隙张开、泥质充填,裂面严重风化锈染。研究表明,谷底松弛是由于河流切至谷底时造成应力集中,导致岩体剪切破坏;并经过漫长的卸荷回弹及风化作用在谷底形成一定厚度的松弛带。