新型多孔聚苯胺在超级电容器电极材料中的应用

通过一个简便的方法,将苯胺单体在含氯化钾(KCl)的盐酸溶液中聚合制备出多孔聚苯胺(polyaniline,PANI).以KC1作为形成多孔聚苯胺的赝模板,既有效地避免了有机溶剂和硬/软模板的使用,又减轻了对环境的污染.由于具有独特的多孔结构和相互交错的纳米棒结构,多孔聚苯胺的比表面积较大,显示出良好的电化学性能.电化...     

Quantum Size-Dependent Third-Order Nonlinear Optical Susceptibility in Semiconductor Quantum Dots

The density matrix approach has been employed to investigate the optical nonlinear polarization in a single semiconductor quantum dot(QD). Electron states are considered to be confined within a quantum dot with infinite potential barriers. It is shown, by numerical calculation, that the third-order nonlinear optical susceptibilities for a typical Si quantum dot is dependent on the quantum size of the quantum dot and the frequency of incident light.     

聚苯胺纳米复合材料用于癌症诊疗的研究进展

共轭聚合物以其独特的结构和性能得到了广泛的关注.聚苯胺（PANI）纳米复合材料制备工艺简单、成本低廉、毒性低、易于功能化,从而在癌症治疗方面取得了巨大的进展.通过不同功能的化合物修饰制备的PANI纳米复合材料极大地拓宽了癌症治疗领域.基于PANI纳米复合材料,文章总结了其在癌症诊疗领域的光热治疗、协同治疗、多模态成像引导治疗和智能响应治疗的研究进展,并分析了其发展趋势.     

活性碳纤维在硫酸介质中电沉积聚苯胺

利用活性碳纤维电极在硫酸溶液中采用循环伏安方法电沉积聚苯胺.随着聚苯胺的生长,循环伏安图中出现四个可逆的氧化还原峰.与聚苯胺的沉积生长对应的阴极沉积电量随着单体浓度、电解质浓度的增大而增大,随着扫描速率增大而减少.理论计算扫描电镜的结果都表明,活性碳纤维电极表面沉积的聚苯胺分为两层,底层为致密的结构,上层为低密度的开放性结构.     

带电粒子在外磁场中磁性的量子尺寸效应

应用ＷＫＢ方法计算了圆柱金属体中带电粒子在外磁场中磁性的量子尺寸效应。结果表明,金属圆柱体半径越小,带电粒子的抗磁性越强,当金属圆柱体半径为１００ｎｍ左右时,其抗磁性是Ｌａｎｄａｕ抗磁性的１０＾４～１０＾６倍。另外,当圆柱体的半径比最大抗磁性半径还小时,带电粒子的抗磁性有振荡行为。     

Quantum size effect of the magnetism of an electron in a metal layer of the layered compounds M/I/M/I…

The energies and the magnetization of an electron in a piece of metal in the structure of Metal/Insulator/Metal/Insulator… (M/I/M/I…), in a magnetic field, at high temperature, and in range of quantum size thickness of the piece of metal layer have been obtained. The results show that when the thickness of the metal layer becomes smaller, the orbital magnetism of the charged particles which collide with the wall of the metal layer is to vary from diamagnetism to paramagnetism. The smaller the thickness of the metal layer becomes, the more particles will collide with the boundary of the metal layer, and then the paramagnetism becomes stronger. Finally, when the thickness of the metal layer becomes very small (<100 nm), all of the orbital diamagnetism will reverse to paramagnetism, and then the paramagnetization will be almost a maximum constant. Foundation item: Supported by the National Natural Science Foundation of China (59602004) Biography: Shen Gou-jin (1959-), male, Associate professor, research direction: theoretical physics.     

Quantum Size Effect of the Magnetism of an Electron in a Metal Layer of the Layered Compounds M/I/M/I…

The energies and the magnetization of an electron in a piece of metal in the structure of Metal/Insulator/Metal/Insulator…(M/I/M/I…), in a magnetic field, at high temperature, and in range of quantum size thickness of the piece of metal layer have been obtained. The results show that when the thickness of the metal layer becomes smaller, the orbital magnetism of the charged particles which collide with the wall of the metal layer is to vary from diamagnetism to paramagnetism. The smaller the thickness of the metal layer becomes, the more particles will collide with the boundary of the metal layer, and then the paramagnetism becomes stronger. Finally, when the thickness of the metal layer becomes very small (＜100 nm), all of the orbital diamagnetism will reverse to paramagnetism, and then the paramagnetization will be almost a maximum constant.     

双三角量子阱中线性及非线性折射率的改变(英文)

利用密度矩阵理论和迭代方法,研究了双三角量子阱中线性、非线性及总折射率改变的特性并以典型的GaAs/AlxGa1-xAs材料为例进行了数值计算.重点讨论了入射光强度、双三角量子阱结构参量(量子阱宽)及外加电场对总折射率改变的影响.计算结果表明:由于线性及非线性折射率遵循着不同的变化规律导致了这些参量对总折射率的改变有着极其重要的影响.     

金属薄膜中的杂质散射效应

考虑到杂质散射效应，运用量子统计的方法，计算金属薄膜中杂质散射的弛豫时间和电导率．计算结果表明：这些物理量都是金属薄膜厚度的函数，具有量子尺寸效应．     

GaN球形量子点中类氢杂质态的二次斯塔克效应

在有效质量近似下,利用微扰-变分法研究了GaN球形量子点中类氢杂质态的二次斯塔克效应.计算了杂质态结合能随量子点半径和外加电场强度的变化关系.数值结果表明,随量子点尺寸和外加电场强度的增加,基态能和结合能均单调降低.此外,随着量子点半径的增大,斯塔克效应变得越来越明显.结果还表明在同一外电场下,球形量子点中杂质态的斯塔克能移较无杂质时导带电子的斯塔克能移小.     

量子点的尺寸效应及声子对激子基态结合能的影响

利用变分法研究了有很小厚度圆盘形GaAs量子点模型中激子的基态结合能,及电子-空穴间距随量子点尺寸变化的规律．考察了电子-空穴的关联明显加强时及完全束缚发生时量子点的横向尺度,初步考虑了体纵光学声子对量子点中激子基态结合能的影响,得出一些定性的结论。     

量子尺寸效应与纳米金属小粒子超导电性

作者考虑到能级分布和能级关联的影响，采用随机矩阵理论，计算了无外场作用时不同粒径超导金属小粒子的两个重要自旋态(s=0，1／2)超导能隙随温度的变化关系，并在自旋s=0时，验证了实验观察所得的超导增强效应。     

量子点量子阱结构中激子的极化效应(英文)

考虑激子与体纵光学声子的相互作用,采用变分法研究了量子点量子阱结构中澈子的极化效应.以CdS/HgS量子点量子阱结构为例进行数值计算,得到了激子的基态能量和束缚能.研究结果表明,声子对澈子束缚能的贡献随着阱宽的增加而增加,极化子效应不能忽略.激子的基态能量和束缚能明显依赖于量子点量子阱结构的核半径和壳层厚度,量子点量子阱结构的尺寸对激子-声子相互作用有重要的影响.     

椭球量子点中施主杂质的三阶非线性光学极化率

在有效质量近似下,采用变分方法,研究椭球量子点中施主杂质的非线性光学性质.基于计算能量和波函数,以典型的半导体材料砷化镓为例,讨论椭球量子点的几何尺寸和各向异性度对施主杂质的三阶非线性极化率的影响.结果显示这些因素对椭球量子点中施主杂质的非线性光学性质有强烈的影响.     

单轴压缩条件下普通混凝土柱的峰后非线性尺寸效应

将单轴压缩条件下遭受到剪切带(峰值应力之后呈现线性应变软化行为)形式的单一剪切破坏普通混凝土试样的峰后应力-应变曲线斜率的解析解推广为非线性情形.在峰值应力之前,采用Scott模型描述非线性的本构关系.剪切带的非线性应变软化本构关系由导出的最短普通混凝土试样峰后斜率反算.利用得到的峰后本构关系,对其他较长的普通混凝土试样的应力-应变曲线进行了预测.预测的峰后应力-应变曲线依赖于试样的高度,且与实验结果吻合.估算的剪切带内部平均塑性剪切应变远大于在单轴压缩条件下测得的轴向应变的极限值.若测得的峰后应力-应变曲线被视为本构关系,则普通混凝土柱的峰后延性将被极大地低估.     

Microstructure and mechanical properties of a novel Zr-based bulk metallic glass composite

Zr48.5Cu46.5Al5 bulk metallic glass （BMG） composites with diameters of 3 and 4 mm were prepared through suction casting in an arc melting furnace by modulating the alloy composition around the monothetic BMG composition of the high glass forming ability. Microstructural characterization reveals that the composites contain micron-sized CuZr phase with martensite structure, as well as nano-sized Zr2Cu crystalline particles and Cu10Zr7 plate-like phase embedded in an amorphous matrix. Room temperature compression tests showed that the composites exhibited significant strain hardening and obvious plastic strain of 7.7% for 3 mm and 6.4% for 4 mm diameter samples, respectively.