基于纳米材料与纳米结构的纳米电源研究进展

随着现代社会的发展和能源危机的来临, 探索和寻找新的能源材料, 开发新能源是人类的永恒课题。自2006年基于ZnO纳米线压电效应的压电式纳米电源问世以来, 又研制出多种基于纳米材料和纳米结构, 以及不同纳米效应的新型纳米电源。本文综述了近10年来, 人们在纳米电源领域的研究成果; 系统介绍了基于压电效应、摩擦效应以及石墨烯能带调控纳米电源的原理和特点, 为今后新型纳米电源的开发提供思路和参考。     

Cell adhesion and migration on nanopatterned substrates and their effects on cell-capture yield

With scanning electron microscopy analysis, we investigated the role of nanoscale topography on cellular activities; e.g.?cell adhesion and spreading by culturing A549 cells (human lung carcinoma cell line cells) for 1-48?h on three sets of nanostructures; quartz nanopillars (QNPs), silicon nanopillars and silicon nanowire (SiNW) arrays, along with planar glass substrates. We found that cells on QNP arrays developed a longer shape than those on SiNW arrays. In addition, we studied how cell morphologies influence the cell-capture yield on the three sets of nanostructures. This research showed that the filopodial formations were directing the cell-capture yield on nanostructured substrates. This finding implies the possibility of using nanoscale topography features to control the filopodial formation including extension and migration from the cells. Using streptavidin-functionalized SiNW substrate, we further demonstrated a substantially higher yield (～91.8?±?5.9%) than the planar glass wafers (～24.1?±?7.5%) in the range of 200-3000 cells.     

AutoCAD中圆环螺旋面的形成与绘图

根据圆柱螺旋线理论,分析了形成圆环螺旋线的要素,并运用解析几何方法建立了圆环螺旋线的参数方程.基于圆柱螺旋面和圆环螺旋线的形成原理,构建了圆环直纹螺旋面的数学模型,讨论了圆环直纹螺旋面的两种表示方法.在AutoCAD环境下,用VisualLisp语言编程,绘制了圆环螺旋线的投影图和三维立体图,并给出了圆环正螺旋面和斜螺旋面的三维CAD造型方法.     

Helium and Hydrogen Adsorbed on Spheres and Cylinders

We examine the metastable and unstable regimes of condensation of superfluid helium and parahydrogen on spheres and cylinders at finite temperatures, employing finite range density functionals. The goal is to compare calculations of sizes and spreads of films at the onset of metastability and of instability with the predictions of a simple phenomenological model that contemplates the curvature of the substrate. We have focused on two cases, helium on nanospheres and nanocylinders of different materials, and hydrogen on fullerenes. We are able to locate the onset of metastability and of spinodal instability in the adsorption isotherms of every sample and to extract the width of the condensed fluid. It is shown that the predictions of the so-called simple model agree surprisingly well with the more elaborate calculations.     

Balancing on tightropes and slacklines

Balancing on a tightrope or a slackline is an example of a neuromechanical task where the whole body both drives and responds to the dynamics of the external environment, often on multiple timescales. Motivated by a range of neurophysiological observations, here we formulate a minimal model for this system and use optimal control theory to design a strategy for maintaining an upright position. Our analysis of the open and closed-loop dynamics shows the existence of an optimal rope sag where balancing requires minimal effort, consistent with qualitative observations and suggestive of strategies for optimizing balancing performance while standing and walking. Our consideration of the effects of nonlinearities, potential parameter coupling and delays on the overall performance shows that although these factors change the results quantitatively, the existence of an optimal strategy persists.     

新校区公寓思想政治工作的制约因素及对策探讨

随着众多大学新校区的建立，新校区公寓学生思想政治工作成为新校区工作的一项重要内容。这项工作好坏及到位与否直接关系列新校区的安全稳定和学校其他工作的开展。分析影响和制约新校区公寓思想政治工作开展的因素，有利于加强和改进这项工作，促进新校区的发展。     

纯铜表面机械沉积镍及其对组织结构和性能的影响

为了提高材料的表面性能,采用表面机械研磨处理和机械合金化相结合的方法,在纯铜表面形成一定厚度的沉积镍层。采用X射线衍射仪(XRD)和扫描电子显微镜(SEM)对试样的显微组织结构进行分析,试样的机械性能采用金相显微硬度测试仪进行测试。实验结果表明,纯铜表面经机械沉积镍处理后,表面平均晶粒尺寸达到了纳米量级;随处理时间的延长,表面硬度得到了改善。     

二氧化硅气凝胶的制备和应用研究

三维纳米网络结构的SiO2气凝胶具有许多独特的性能,在光学、热学、声学、微电子学、高功率激光等领域具有广阔的应用前景,是目前材料科学家研究的热门材料之一.简要评述了SiO2气凝胶的制备技术和应用前景.     

纸张喷墨印刷的网点铺展渗透研究

分析了喷墨印刷中油墨与纸张的使用情况并归纳其特点,以此特点为出发点、以能量为基础建立墨滴在纸张上的铺展、渗透模型,通过获得模型中所需参数来预测喷墨印刷的最终效果,并用分形理论评判其效果.     

Gamma Radiation Induced Effects on Cefuroxime and Cefotaxime. Investigation on Degradation and Syn-Anti Isomerization

The effects of gamna irradiation on cefuroxime and cefotaxime were studied. Degradation products and long-lived free radicals were investigated as a function of radiation dose. The formation of new impurities was evidenced by HPLC in both the compounds. A valuable increase of the pre-existent impurities, anti-isomer included, was found only in cefuroxime. ESR measurements put in evidence the presence of ganma radiation induced long-lived free radicals. Moreover, the influence of gamma irradiation on syn-anti isomerization was evaluated in comparison with the photoisomerization induced by ultraviolet light exposition on powder samples.     

钛合金激光熔覆的研究现状与发展趋势

钛合金具有高比强、良好的耐蚀性能等优点,但其耐磨性差,限制了它在摩擦机构的应用.激光熔覆技术是近年来发展起来的一种新型表面改性工艺.在钛合金表面进行激光熔覆,可提高钛合金的表面性能,获得高硬度、耐磨性能好、低摩擦系数的熔覆层.简要阐述了钛合金表面激光熔覆的研究现状,包括激光熔覆工艺、熔覆层的组织与性能,指出了存在的问题,并展望了钛合金激光熔覆的发展方向.     

Gamma Radiation Induced Effects on Cefuroxime and Cefotaxime. Investigation on Degradation and Syn-Anti Isomerization

The effects of gamna irradiation on cefuroxime and cefotaxime were studied. Degradation products and long-lived free radicals were investigated as a function of radiation dose. The formation of new impurities was evidenced by HPLC in both the compounds. A valuable increase of the pre-existent impurities, anti-isomer included, was found only in cefuroxime. ESR measurements put in evidence the presence of ganma radiation induced long-lived free radicals. Moreover, the influence of gamma irradiation on syn-anti isomerization was evaluated in comparison with the photoisomerization induced by ultraviolet light exposition on powder samples.     

Glitter and glints on water

We present new observations of glitter and glints using short and long time exposure photographs and high frame rate videos. Using the sun and moon as light sources to illuminate the ocean and laboratory water basins, we found that (1) most glitter takes place on capillary waves rather than on gravity waves, (2) certain aspects of glitter morphology depend on the presence or absence of thin clouds between the light source and the water, and (3) bent glitter paths are caused by asymmetric wave slope distributions We present computer simulations that are able to reproduce the observations and make predictions about the brightness, polarization, and morphology of glitter and glints. We demonstrate that the optical catastrophe represented by creation and annihilation of a glint can be understood using both ray optics and diffraction theory.     

基于纳米材料的气凝胶制备及应用

气凝胶是一种三维多孔材料,具有孔隙率高、比表面积大、密度低等特性。以纳米材料构筑气凝胶可进一步调控孔隙结构、改善机械强度,同时还能赋予气凝胶高导电性、低热导率、高吸附性和隔音吸声等特性,在储能、保温隔热、吸附材料等领域有重要的应用。重点对近年以纳米颗粒、纳米纤维素、碳纳米纤维、碳纳米管、石墨烯等不同形态纳米材料构筑的气凝胶的制备、结构、性能和应用进行了综述,同时展望了气凝胶的发展前景与方向。     

Quantitative research on effects of stresses and strains on bainitic transformation kinetics and transformation plasticity

Abstract

In this paper, the effect of stress and strain on bainitic transformation kinetics and transformation plasticity have been studied quantitatively by means of experiments on a Gleeble-1500 testing machine. It is concluded that applied stresses will promote the evolution of bainitic transformation and increase the maximum volume fraction of the new phase and increase the value of the transformation plasticity parameter. Moreover, predeformation due to applied stress affects both the maximum volume fraction of the new phase and the value of the transformation plasticity parameter with increasing applied stress; but it has little effect on the variation of transformation kinetics parameter with the applied stresses.     

涡旋压缩机吸、排气管路结构研究

对于大型商用空调而言,管路应力应变是关系到整个机组可靠性的重要因素.本文通过实验分析总结出较为适宜涡漩压缩机的吸、排气管结构.     

基于仿生原理的几何构型及其功能性的研究进展

近年来,从生物形态出发的仿生学研究已得到广泛的关注。模拟生物表面形态、分析生物因其自身形态而具备的功能,并将其应用到工程领域中已成为研究热点之一。研究基于仿生学原理的生物体几何形貌及其所具备的功能,能够优化材料表面性能,延长服役寿命,拓宽应用范围,提高材料的应用价值。本文通过分析生物体因体表几何构型而具备的超疏水性、仿生减阻性、减摩耐磨性的原理及应用领域,探究仿生织构化图案实现不同功能的机理,明确其未来着力于仿生图案的制备及机理探索的发展方向,进而对材料表面进行处理,以期具备更优异的性能。     

XML和TXT在包层模板描述中的应用和比较

对XML和文本文件在模板语言的描述和实现中的应用进行了研究，针对模板、XML和txt的特点提出了比较参数体系并进行了实验比较。比较发现，XML的模板描述的清晰性、可读性、可扩展性及网络协同方面的指标显著优于txt文件：而文本文件则在文件的大小、实现代码量、模板解释时间性能上略占优势。     

Comparison of visual similarity judgement on computer screens and on paper

This article reports a study of how visual similarity judgement differs between the two media. Participants of the study judged dissimilarities of web pages both on screens in computer-based tasks and on printouts in paper-based tasks. Significant difference in similarity judgement was found between computer and paper tasks. This difference could neither be explained by the ecological difference in using computers and printouts, nor be explained by visual difference. The availability of interactive features of web pages on screens, compared to the lack of them on printouts, could account for the observed difference in similarity judgement, even though the features are not relevant to the tasks. The result highlights the significance of interactive features as parts of context change when tasks are moved between the two media.     

Study by AES and EELS spectroscopies of antimony and phosphorus evaporated on massive indium and on cleaned InP

In this paper, we give some results related to interaction mechanism between the elements V such as antimony or phosphorus with the metal indium. We used both powerful spectroscopy methods the Auger electron spectroscopy (AES) and the electron energy loss spectroscopy (EELS) for which the spectra were recorded in direct mode N(E). The antimony was evaporated on pure In metal or on cleaned InP surface involving the In metal because of its cleaning by the argon ion bombardment at low energy 300 eV. The antimony flow composed of Sb₄ species arrived with a thermal energy on the In metal surface. Such an energy was sufficient to their diffusion into the In matrix because of the low melting point of In metal (123 °C). A nucleation phenomenon occurred between Sb₄ and the In metal to form small islands of antimony metal in bulk. Further antimony evaporation enabled to increase the size of these islands towards the surface. However, the antimony evaporated on cleaned InP reacted chemically with the In metal distributed on the InP surface to form a thin layer of InSb. The inner stoichiometric layers of InP and the size of Sb₄ species and also the stability of InP versus the temperature impeded the interdiffusion phenomenon of antimony to occur deeply into the InP matrix. The InSb layer played the role to stabilise the surface of the InP compound versus the heating at 450 °C and the electron irradiation of 4 KeV energy. But, the phosphorus evaporation on In metal or on cleaned InP led to form chemical bonds InP. The phosphorus flow included chemical species P and P₂ with a thermal energy able to stimulate the chemical reactivity process between indium and phosphorus to form the InP compound.