电子光学模型实验(英文)

本实验通过电场和磁场对发散电子束的会聚作用，证明了“电子光学透镜”与光学透镜在原理上的相似性．

电子透镜的两种逆设计方法比较

分别讨论了最小二乘法和神经网络法用于电子光学透镜逆设计的情况,并比较了各自优缺点。可以看到在较好的选取学习样本情况下,神经网络技术在电子透镜的逆设计中有着明显的优越性。

半球形偏转电子能量分析器的设计和应用

本文较详细地介绍了静电半球偏转电子能量分析器的原理、设计和实际制作，并说明半球分析器作为单色器和分析器在中能电子能量损失谱仪（ＥＥＬＳ）的成功使用。

片状八极透镜特性的研究

本文研究了一种新型电子光学透镜──片状八极透镜．推导了该透镜场分布近似表达式，进而分析其特性．根据大量数值计算结果绘出一组特性曲线，验证了理论推导结果．最后提出利用该透镜校正梯形畸变的设计方案，并证明了它的可行性．

Influence of thermomechanical aging on microstructure and mechanical properties of 2519A aluminum alloy

The influence of thermomechanical aging on microstructure and mechanical properties of 2519A aluminum alloy was investigated by means of microhardness test,tensile test,optical microscopy (OM) and transmission electron microscopy (TEM).The results show that 50% cold rolling deformation prior to aging is beneficial since it promotes a more homogeneous distribution of the precipitation phase and reduces the number of precipitation phase on the grain boundaries,and thus shrinks the total volume of precipitation-free zones at grain and sub-grain boundaries.As a result,the tensile properties of 2519A aluminum alloy have been significantly improved.

Pre-dispersed carbon black as conductive agent for LiFePO_4 cathodes

High dispersed carbon black was applied for LiFePO4 cathodes as conductive agent.Nano-conductive carbon agent was pre-dispersed with poly acrylic acid(PAA) as dispersant in organic N-methyl-pyrrolidone(NMP) solvent system.The dispersion property of nano-conductive carbon agent was evaluated using particle size distribution measurements,scanning electron microscopy(SEM) and transmission electron microscope(TEM).LiFePO4 cathode with as-received nano-conductive carbon agent(SP) and LiFePO4 cathode with pre-dispersed nano-conductive carbon agent(SP-PAA) were examined by scanning electron microscopy(SEM),cyclic voltammetry(CV),electrochemical impendence spectroscopy(EIS) and charge/discharge cycling performance.Results show that the dispersion property of carbon black is improved by using PAA as the dispersant.The LiFePO4 cathodes with SP-PAA exhibit improved rate behaviors(4C,135.1 mAh/g) and cycle performance(95%,200 cycles) compared to LiFePO4 cathodes with SP(4C,103.9 mAh/g and 83%,200 cycles).Because pre-dispersed carbon black(SP-PAA) is dispersed homogeneously in the dried composite electrode to form a more uniform conductive network between the active material particles,electrochemical performances of the LiFePO4 cathodes are improved.

In-situ interaction of nano-PbS with gelatin

Water-soluble gelatin-PbS bionanocomposites （BNCs） were synthesized via a facile one-pot chemical reaction method at pH 7.40. The samples were characterized by transmission electron microscopy （TEM）, X-ray diffraction （XRD）, UV-vis absorption spectra （UV-vis）, Fourier transform infrared spectra （FT-IR） and circular dichroism （CD）. FT-IR data were used to envis- age the binding of PbS particles with oxygen atoms of carbonyl groups of gelatin molecule. The possible integration mechanism between gelatin and PbS was discussed in detail. The effect of Pb2＋ and PbS on the conformations of gelatin has also been analyzed by means of UV-vis, CD and FT-IR spectra, resulting in less c^-helix content and more open structures （[3-sheet, r-turn, or expanded）. A new formula to calculate the association constant was proposed according to the relationship between the absorbance of gelatin-PbS BNCs and the free concentration of PbS, and apparent association constants K （298/303/308 K： 3.11/2.00/1.60 × 10^6 tool/L） at three different temperatures were calculated based on this formula. Thermodynamic parameters such as AG^θ, △Hθ and △S^θ were also determined. The results of the thermodynamic investigations indicated that the reaction was spontaneous （AG^θ 〈 0）, and enthalpy-driven （△H^8 〈 0）.

Reversible photoswitching self-assembly of azobenzene-functionalized hyperbranched polyglycerol induced by host-guest chemistry

Reversible assembly and disassembly of rodlike large complex micelles have been achieved by applying photoswitching of supramolecular inclusion and exclusion of azobenzene-functionalized hyperbranched polyglycerol and acyclodextrin as driv ing force, promising a versatile system for selfassembly switched by light. Hydrogennuclear magnetic resonance （H NMR） and Fourier transform infrared （FTIR） spectroscopy were applied to characterize the azobenzenefunctionalized hyperbranched polyglycerol. Atomic force microscopy （AFM）, transmission electron microscopy （TEM） and dynamic laser light scattering （DLS） were employed to investigate and track the morphology of the rodlike large complex micelles before and after irradiation of UV light.