四边固支球面扁壳的解析解

本文用解析法四边固支球面扁壳的在均布荷载作用下的内力和挠度进行了计算。     

Selected‐Control Fabrication of Multifunctional Fluorescent–Magnetic Core–Shell and Yolk–Shell Hybrid Nanostructures

The selected‐control preparation of uniform core–shell and yolk–shell architectures, which combine the multiple functions of a superparamagnetic iron oxide (SPIO) core and europium‐doped yttrium oxide (Y₂O₃:Eu) shell in a single material with tunable fluorescence and magnetic properties, has been successfully achieved by controlling the heat‐treatment conditions. Furthermore, the shell thickness and interior cavity of SPIO@Y₂O₃:Eu core–shell and yolk–shell nanostructures can be precisely tuned. Importantly, as‐prepared SPIO@Y₂O₃:Eu yolk–shell nanocapsules (NCs) modified with amino groups as cancer‐cell fluorescence imaging agents are also demonstrated. To the best of our knowledge, this is the first report on the selected‐control fabrication of uniform SPIO@Y₂O₃:Eu core–shell nanoparticles and yolk–shell NCs. The combined magnetic manipulation and optical monitoring of magnetic–fluorescent SPIO@Y₂O₃:Eu yolk–shell NCs will open up many exciting opportunities in dual imaging for targeted delivery and thermal therapy.     

Using Simple Spray Pyrolysis to Prepare Yolk–Shell‐Structured ZnO–Mn3O4 Systems with the Optimum Composition for Superior Electrochemical Properties

A spray‐pyrolysis process is introduced as an effective tool for the preparation of yolk–shell‐structured materials with electrochemical properties suitable for anode materials in Li‐ion batteries (LIBs). Yolk–shell‐structured ZnO–Mn₃O₄ systems with various molar ratios of the Zn and Mn components are prepared. The yolk–shell‐structured ZnO–Mn₃O₄ powders with a molar ratio of 1:1 of the Zn and Mn components are shown to have high capacities and good cycling performances.     

A Sub‐50‐nm Monosized Superparamagnetic Fe3O4@SiO2 T2‐Weighted MRI Contrast Agent: Highly Reproducible Synthesis of Uniform Single‐Loaded Core–Shell Nanostructures

Oleic acid stabilized superparamagnetic iron oxide nanoparticles (SPION) were selected as the cores for fabrication of sub‐50‐nm monodisperse single‐loaded SPION@SiO₂ core–shell nanostructures. Parameters that influence the formation of SPION@SiO₂ in the water‐in‐oil reverse microemulsion system have been systematically investigated. The sufficiently high concentration of well‐dispersed SPION, together with an appropriately low injection rate of tetraethoxysilane, were found to be the keys to efficiently prevent the homogeneous nucleation of silica and obtain a high‐quality single‐loaded core–shell nanocomposite. A more detailed mechanism for incorporating oleic acid capped inorganic functional nanoparticles into silica is proposed on the basis of previous reports and our new experimental results. Finally, the as‐synthesized SPION@SiO₂ nanospheres are exploited as an MRI‐enhanced contrast agent, and their contrast effect in solution is tested by using a clinical MRI instrument.     

Reversible Modulation of Surface Plasmons in Gold Nanoparticles Enabled by Surface Redox Chemistry

Switchable surface redox chemistry is demonstrated in gold@iron/iron oxide core–shell nanoparticles with ambient oxidation and plasmon‐mediated reduction to modulate the oxidation state of shell layers. The iron shell can be oxidized to iron oxide through ambient oxidation, leading to an enhancement and red‐shift of the gold surface plasmon resonance (SPR). This enhanced gold SPR can drive reduction of the iron oxide shell under broadband illumination to reversibly blue‐shift and significantly dampen gold SPR absorption. The observed phenomena provide a unique mechanism for controlling the plasmonic properties and surface chemistry of small metal nanoparticles.     

壳层可控导电聚吡咯/聚苯乙烯复合微球及聚吡咯中空微胶囊的制备

在导电聚合物含量较小时,含核壳结构的导电聚合物复合粒子就可以具有和本体相当的导电率,且加工性好,近年来这种核壳结构微粒的制备已引起了科学家们的广泛关注．Armes等[制备了导电聚吡咯、导电聚苯胺包覆聚苯乙烯的核壳结构胶体粒子及聚苯胺和二氧化硅的纳米复合物．刘正平等用改进的方法在粒径为116nm的单分散聚苯乙烯乳胶粒子上包覆聚吡咯,     

投影壳模型研究丰中子奇奇核102,104Nb的转动能谱

运用投影壳模型研究了正常形变丰中子核同位素102,104Nb的低能级能谱, 并指定了它的准粒子组态, 理论计算所得到的能谱曲线与实验给出的能谱曲线非常一致, 说明了投影壳模型对研究重核低能级谱非常有效。 The Projected Shell Model(PSM) is used to study the low energy scheme of the neutron rich normal deformed isotopes of odd odd nuclei 102, 104Nb. The quasiparticle configuration is assigned. The theoretical calculations of the energy band of 102,104Nb could well reproduce the experimental data. It is shown that PSM is a valid method for studying the low energy scheme of heavy nuclei.     

Core/Shell Structured PCM Nanocapsules Obtained by Resin Fortified Emulsion Process

Phase change material (PCM, octadecane) nanocapsules were successfully prepared by resin fortified emulsion (RFE) polymerization using the alkali soluble resin (ASR) of poly(ethylene‐co‐acrylic acid) (EAA) and poly(styrene‐co‐acrylic acid) (SAA). Stable PCM nanocapsules were obtained by resin fortified emulsion polymerization, which could be attributed to the prevention of Ostwald ripening due to PCM being hydrophobic. Analysis of online FTIR measurements throughout the reaction confirmed that the nanocapsules contained octadecane as a PCM. TEM imaging of the PCM nanocapsules showed spherical and core/shell morphology. The characteristics of PCM nanocapsules can be controlled by process parameters. As a result, the particle size and particle size distribution (i.e., polydispersity index (Dw/Dn)) of the PCM nanocapsules were created by adjusting manufacturing conditions. The PCM nanocapsules exhibited thermal energy storage (～49.8 J/g) and release (～47.9 J/g) behavior.     

叠层连续开口圆柱壳的精确解

抛弃任何有关位移和应力模式的假设，引入δ-函数，对正变异性连续开口圆柱壳建立状态方程．给出薄的、中厚的和强厚的叠层连续开口圆柱壳静力问题的统一的精确解．数值结果和SAPS解进行了对比．