透射电镜在仿硅藻结构的介孔二氧化硅表征和制备中的应用

透射电子显微镜由于其高分辨率广泛应用于材料研究中。利用透射电镜对材料进行表征,可以更好地研究材料的微观结构特征,揭示宏观现象与介观和微观结构间的关系,并开发出具有特异性能的新材料。本实验用苯甘氨酸衍生物为模板制备出类似硅藻结构的纳米介孔二氧化硅,用透射电子显微镜研究了反应组成的变化对硅藻结构的介孔二氧化硅纳米材料制备和形貌结构的影响。     

基于AFM湿度对表面粘着力影响的研究

微观表面力测量技术已经成为研究微观界面物理、纳米材料和纳米机械学等领域的重要手段,本文介绍了利用原子力显微镜(AFM)进行固体表面长程粘着力的测量,并分析了在大气条件下,不同湿度对表面粘着力的影响.     

纳米绝缘材料的STM检测机理及其应用研究

分析了纳米绝缘材料薄层在适当的偏压电场下STM检测的机理,用自行研制的STM.IPC-205B型扫描隧道显微镜实现了对部分绝缘纳米材料微观形貌的检测,得到了理想的图像.拓展了STM检测加工技术的应用领域,进一步发挥了STM在材料结构和性能研究方面精度高、稳定性强等优势.     

纳米材料在涂料中的应用进展

介绍了近年来国内外有关纳米材料在涂料中的应用和研究开发情况,阐述了涂料用纳米材料的主要特征,提出了纳米材料在涂料中应用所存在的主要问题及解决方法。     

大应变切削加工制备纳米材料方法的探究

控制切削参数使变形区域的金属发生较大变形,拉长晶粒,从而获得亚微米及纳米级结构的切屑材料.该方法突破了现有方法的限制,不仅可以在一道工序中获得硬度从低到中高的纳米金属和合金材料,而且可以通过改变工艺参数方便地对纳米材料微观结构成形机理进行系统的研究,是一种可以低成本大批量制备各种纳米材料的有效方法.     

什么是准一维纳米材料?

准一维纳米材料是指在两维方向上为纳米尺度,长度为宏观尺度的新型纳米材料。早在１９７０年法国科学家就首次研制出直径为 ７纳米的碳纤维． １９９１年日本首次用高分辨电镜发现了碳纳米管。我国科学家也成功合成了世界上最长的碳纳米管。碳纳米管的研究,推动了整个准一维纳米材料的研究．近十年里,人们利用各种方法又陆续合成了多种准一维纳米材料,如纳米棒、纳米线、半导体纳米量子线、纳米线阵列等．法国、日本等国科学家于１９９７年和１９９８年相继研制成功同轴纳米电缆．１９９６年,中科院固体物理所纳米结构研究组研制成功各…     

纳米材料干燥技术的研究和发展

纳米材料干燥是液相法制备纳米材料过程中一个不可缺少的重要步骤。本文介绍了纳米材料的干燥特点，简要评述了目前纳米材料研究或生产过程中所采用的一些干燥方法，评价了纳米材料干燥技术的研究现状，并指出了未来的研究和发展方向。     

纳米材料作为润滑添加剂的研究回顾及目前的发展动向与展望

回顾了纳米材料作为润滑添加剂的研究状况。比较了不同纳米材料添加剂对摩擦学性能的影响；综述了纳米材料的抗磨减摩机理。介绍当今国外此领域的研究现状，指出结构型纳米材料是在本领域的研究新热点。并展望了纳米材料作为润滑油添加剂的发展方向。     

纳米材料的奇异特性及其应用前景

叙述了自然界中存在的纳米材料，由此引出纳米材料的许多奇异特性，并展望了纳米材料的应用前景。     

纳米材料的研究现状和发展趋势

本文详细阐述了纳米材料研究的现状和发展趋势，讨论了纳米材料不同研究阶段的内涵，特点和取得的成果；分析了纳米材料发展的几个热点领域，对纳米材料发展的趋势进行了展望。     

Hydrothermal Synthesis,Characterization, and Tribological Behavior of Oleic Acid-Capped Lanthanum Borate with Different Morphologies

In this paper, nano/microstructure lanthanum borates were synthesized by hydrothermal route. Furthermore, oleic acid-capped nano/microstructure lanthanum borates (OANLBs) were also prepared. The nano/microstructure of lanthanum borate is characterized by means of Fourier transform-infrared spectroscopy (FT-IR), field-emission scanning electron microscopy (FE-SEM), and transmission electron microscopy (TEM). At the same time, the friction and wear properties of OANLBs as additives in poly-alpha-olefin (PAO) were measured for AISI 1045 steel and laser treated AISI 1045 steel. Results show that the PAO containing OANLBs possesses much better tribological properties for steel/steel and steel/laser treated AISI 1045 steel sliding pairs than pure PAO.     

Application of nano powdered rubber in friction materials

Styrene butadiene nano powdered rubber and nitrile-butadiene nano powdered rubber were used for manufacturing clutch facings, disc brake pads and brake linings to replace conventional styrene butadiene rubber and nitrile-butadiene rubber. The results of constant speed friction test and dynamometer test showed that nano powdered rubber can substantially improve properties of friction materials. The friction coefficient of friction materials modified with nano powdered rubber varies steadily with the change of temperature, and the wearing rate of friction materials is relatively low by using nano powdered rubber. These results indicate that nano powdered rubber has ideal application effect in various friction materials and is a kind of novel rubber modifier for friction materials.     

纳米PTFE复合镀层的组织和摩擦性能

采用扫描电镜、透射电镜和X-射线衍射仪分析了纳米PTFE复合镀层的表面形貌和组织结构,利用微米划痕法在MXTX S/X型划痕试验仪上研究了纳米复合镀层的摩擦因数随PTFE含量变化的情况。研究结果表明:纳米PTFE的加入明显细化复合镀层。纳米PTFE以颗粒形式存在于镀层中。纳米复合镀层的摩擦因数明显低于未加纳米的镀层。当纳米PTFE的含量为15.0 g/L时,纳米复合镀层的摩擦因数最小(0.046)。     

纳米晶脉冲电铸的试验研究

通过理论分析和试验研究 ,利用高频脉冲电流、高速冲液及添加剂方法 ,获得了纳米晶电铸层。分析了在脉冲电铸过程中 ,电规准及添加剂对沉积层微观结构影响     

Application of nano electrolyte in the electrochemical discharge machining process

As a nontraditional machining process, electrochemical discharge machining (ECDM) can apply to hard and brittle materials such as glass and ceramic. Improvement of process efficiency is an important topic that has been addressed in many investigations using various techniques such as magnetic field and ultrasonic vibrations.Nano particles are new and advanced materials that can be dispersed in a fluid to obtain a nano fluid with desirable specifications. This method can be implemented in the ECDM process by the application of the nano electrolyte. Nano electrolyte can present enhanced properties, in particular enhanced electrical and thermal conductivities which lead to more powerful discharges and greater material removal.In order to study the variation of discharge physics, consequent captures from discharges were taken. Besides using current signal diagrams, larger numbers of discharges were found using nano electrolytes. Results of hole depth showed that both Cu and Al₂O₃ nano electrolytes improved the hole depth as 21.1% and 18.7%, respectively. An undesirable effect of nano electrolyte was observed on the entrance overcut, which raised 8.3% and 10.7% using Cu and Al₂O₃ nano electrolytes, respectively, in comparison to the simple electrolyte. This drawback is negligible compared to the significant improvement of hole depth. SEM images of tool wear showed larger molten materials on the tool main edges by the application of nano electrolyte.     

Nano Si3N4 composites with improved tribological properties

Nano Si₃N₄ composites with tailored microstructure were developed using fine ß‐Si₃N₄ powders. Their wear behaviour was investigated. Whereas pure Si₃N₄ composites showed improved wear behaviour under dry rolling conditions with slip, TiN‐reinforced nano Si₃N₄ composites generate a self‐lubricating behaviour under dry sliding conditions. After chemical treatment with hydrogen sulphide, the friction coefficient and wear rate was found to be significantly decreased under dry sliding conditions. Additionally, the new composites possess higher fracture toughness than the pure nano Si₃N₄ materials. Copyright © 2009 John Wiley & Sons, Ltd.     

微纳米生物制造技术的基础研究

叙述采用生物加工方法实现微纳米材料、微纳米器件、微纳米系统制造的技术体系。介绍微纳米生物加工的最新进展 ,展望生物加工领域的未来发展趋势。     

Laser‐preparation of geometrically optimised samples for X‐ray nano‐CT

A robust and versatile sample preparation technique for the fabrication of cylindrical pillars for imaging by X‐ray nano‐computed tomography (nano‐CT) is presented. The procedure employs simple, cost‐effective laser micro‐machining coupled with focused‐ion beam (FIB) milling, when required, to yield mechanically robust samples at the micrometre length‐scale to match the field‐of‐view (FOV) for nano‐CT imaging. A variety of energy and geological materials are exhibited as case studies, demonstrating the procedure can be applied to a variety of materials to provide geometrically optimised samples whose size and shape are tailored to the attenuation coefficients of the constituent phases. The procedure can be implemented for the bespoke preparation of pillars for both lab‐ and synchrotron‐based X‐ray nano‐CT investigations of a wide range of samples.     

微/纳米级压电材料的制备方法

由于电子、通讯和控制等高新技术行业的迅速崛起,对材料的高性能、多功能、小型化、智能化等的需求越来越高,使得对微/纳米级压电材料的制备受到重视,并且微/纳米级压电材料是压电复合材料的重要组成部分,本文介绍五种微/纳米级压电材料的制备方法.     

纳米连接过程的分子动力学模拟研究进展

纳米材料因其特有的结构和性能而得到广泛的应用，纳米连接技术也随之发展起来。在纳米加工领域，虽然有很多先进的显微分析手段，但由于实时观察技术的限制，材料的很多现象和行为很难通过实验进行观测和分析，而分子动力学适用于几纳米到几十纳米的三维空间尺度和纳秒以下的时间尺度，同纳米加工领域很多过程的时间尺度和空间尺度保持一致，因此，利用分子动力学模拟纳米材料性能和连接过程原子的动力学行为是可行的。综述了纳米材料（包括纳米多层膜、纳米线、碳纳米管、纳米颗粒）在纳米连接过程以及连接大尺寸材料过程中的分子动力学模拟研究进展，模拟结果与实验结果基本吻合。结合最新研究进展，讨论了分子动力学模拟在纳米连接应用中的存在问题、解决办法和发展趋势。