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1.
卜笑庆  张锦龙  潘峰  刘华松  樊荣伟 《红外与激光工程》2018,47(9):921001-0921001(6)
利用离子辅助电子束双源共蒸发工艺方法,制备了SiO2掺杂含量分别为0、13%、20%、30%、40%和100%的六组HfO2-SiO2混合膜。采用纳米压痕法测量了不同组分混合膜的杨氏模量和硬度,并研究了混合膜杨氏模量和硬度随SiO2含量增长的变化规律。结果显示,随着SiO2含量增加,混合膜杨氏模量和硬度均减小,双组分复合材料并联模型可以较好地拟合杨氏模量随混合膜SiO2含量变化关系。为了解释混合膜力学性能随SiO2含量变化规律,对混合膜进行了XRD测试,研究了混合膜微观结构与杨氏模量和硬度的关系,发现结晶对硬度影响显著,对杨氏模量影响较小;用Zygo干涉仪测量了样品的面形,获得了薄膜残余应力随SiO2含量的变化规律,表明SiO2掺杂能减小HfO2薄膜压应力。  相似文献   

2.
石墨和纳米SiC填充PEEK磨损机理的研究   总被引:2,自引:0,他引:2  
研究发现纳米SiC能显著改善其填充PEEK复合材料在干摩擦状态下的摩擦学性能。纳米SiC填充PEEK的主要磨损机制是轻微的粘着转移和疲劳磨损[1]。石墨作为常用的固体润滑剂多年来已经得到了广泛的应用[2]。作者研究了纳米SiC和石墨共同填充PEEK复合材料在干摩擦状态下的摩擦和磨损性能,为了简化试验,两种填料中纳米SiC的含量固定为3.3vol.%[1],而逐渐增加石墨的含量,研究发现Gr-SiC-PEEK复合材料中Gr.含量较低时(<3.0vol.%),纳米SiC和Gr.有协同效应,使Gr.-纳米SiC-PEEK复合材料的摩擦磨损性能进一步得到改善;当Gr.含量大于3.0v…  相似文献   

3.
文章研究了纳米SiO2作为涂料添加剂对丙烯酸树脂导电涂料导电性能的影响,测试了加入不同量纳米SiO2时涂层的体积电阻;用扫描电镜观察了导电涂层的表面及截面形貌,用XRD研究了镀银铜粉的结构特性。结果表明在镀银铜粉涂料中加入适量的纳米SiO2可以提高其导电性能,同时还观察到纳米SiO2可以加快涂料的固化速度,增加膜层与基板的结合度。  相似文献   

4.
聚酰亚胺(PI)/无机纳米复合材料是一种性能优异的新型复合材料。本文概述了聚酰亚胺(PI)/无机纳米复合材料的制备方法,介绍了近几年来不同类型的聚酰亚胺(PI)/无机纳米复合材料的研究现状及在覆铜板上的应用,并对其发展进行了展望。  相似文献   

5.
采用X—ray衍射分析、差示扫描量热及扫描电镜等手段,研究了Li2O—MgO—Al2O3—SiO2系统中晶化剂TiO2不同添加量和晶化热处理工艺对纳米相微晶玻璃制备的影响,探讨了TiO2的晶化机理。实验结果表明:足够的TiO2含量(大于7.5%)是获得纳米相微晶玻璃的关键;TiO2含量为10.0%时,在合适的晶化热处理条件下,可制得晶粒分布均匀、数量众多、结晶分数达40%、晶粒尺寸约为80nm的尖晶石微晶玻璃,其适宜用作高性能硬盘基片。  相似文献   

6.
纳米结构工程的改建和修饰,是在基本结构框架的基础上,通过部分结构的变化和调整,使纳米材料获得更多的物理性能,有时甚至获得更好和更新的性能。本工作将涉及:(1)纳米生物工程中的基本结构框架为钙三角通道,其尺寸为0.7nm;(2)介孔微纳复合材料的基本结构单元,其尺寸为0.5~0.6  相似文献   

7.
郜文婕  李青山   《电子器件》2007,30(6):1991-1994
综述了聚乙烯醇缩丁醛/纳米复合材料的国内外制备现状,介绍了纳米复合材料的发展、分类、结构与性能及PVB的广泛用途;并展望了其未来研究的发展方向以及在环境设计中的应用.通过采用共混法在聚乙烯醇缩丁醛材料中引入纳米SiO2粒子制备了均匀的PVB/SiO2复合材料.以UV-VIS,FT-IR,XRD,SEM等现代测试手段表征了材料的微观形貌、结构和光学性能.结果表明:由于纳米SiO2粒子的引入,使PVB/SiO2复合材料具有良好的紫外线屏蔽性能.同时,材料的韧性得到明显提高,其断裂伸长率为纯PVB材料的8倍.具有一定的工业应用前景.尤其,能够解决环境设计中相关材料的光污染问题.  相似文献   

8.
利用射频磁控溅射方法,制成纳米SiO2层厚度一定而纳米Si层厚度不同的纳米(SiO2/Si/SiO2)/p-Si结构和纳米(SiO2∶Al/Si/SiO2∶Al)/p-Si结构,用磁控溅射制备纳米SiO2∶Al时所用的SiO2/Al复合靶中的Al的面积百分比为1%.上述两种结构中Si层厚度均为1—3nm,间隔为0.2nm.为了对比研究,还制备了Si层厚度为零的样品.这两种结构在900℃氮气下退火30min,正面蒸半透明Au膜,背面蒸Al作欧姆接触后,都在正向偏置下观察到电致发光(EL).在一定的正向偏置下,EL强度和峰位以及电流都随Si层厚度的增加而同步振荡,位相相同.但掺Al结构的发光强度普遍比不掺Al结构强.另外,这两种结构的EL具体振荡特性有明显不同.对这两种结构的电致发光的物理机制和SiO2中掺Al的作用进行了分析和讨论.  相似文献   

9.
有机薄膜晶体管阈值电压漂移现象的研究   总被引:5,自引:3,他引:2  
研究了有机薄膜晶体管(Oganic thin film transistor,OTFT)的阈值电压漂移与栅偏置电压和偏置时间的关系、不同栅绝缘膜对OTFT阈值电压漂移的影响以及不同栅绝缘膜MIS结构的C-V特性。结果发现.栅偏置电压引起了OTFT转移特性曲线的平移而场效应迁移率(μFE)和亚阈值陡度(△S)不变;阈值电压漂移的量与偏置时间的对数呈线性关系。还发现阈值电压漂移量与栅绝缘膜绝缘性能有关,绝缘性能好的绝缘膜(如SiO2)器件阈值电压漂移量小.绝缘性能差的绝缘膜(如TaOx)器件阈值电压漂移量大。认为有机晶体管阈值电压漂移是由沟道载流子以直接隧穿方式进入栅绝缘膜内的陷阱造成的。  相似文献   

10.
Sb:SnO2/SiO2纳米复合薄膜的光学及气敏特性   总被引:1,自引:0,他引:1  
采用溶胶-凝胶(sol-gel)工艺制备了Sb:SnO2/SiO2复合膜。通过原子力显微镜(AFM)观察了薄膜样品的表面形貌,利用紫外-可见光谱,p-偏振光反射比角谱研究了复合薄膜的光学特性。结果表明,薄膜中的晶粒具有纳米尺寸(~35nm)的大小,比表面积大,孔隙率高;薄膜的透光率高,可见光波段近95%;其光学禁带宽度约3.67eV。因此Sb:SnO2/SiO2纳米复合膜可作为气敏薄膜的理想选择。通过对三种不同的气体C3H8,C2H5OH及NH3气敏特性的测试表明,Sb掺杂大大提高了SnO2薄膜对C2H5OH的灵敏度,纳米Sb:SnO2/SiO2复合膜的气敏灵敏度高于纯SnO2薄膜及Sb掺杂的SnO2薄膜。  相似文献   

11.
From its emergence in the late 1980s as a lower cost alternative to early EEPROM technologies, flash memory has evolved to higher densities and speedsand rapidly growing acceptance in mobile applications.In the process, flash memory devices have placed increased test requirements on manufacturers. Today, as flash device test grows in importance in China, manufacturers face growing pressure for reduced cost-oftest, increased throughput and greater return on investment for test equipment. At the same time, the move to integrated flash packages for contactless smart card applications adds a significant further challenge to manufacturers seeking rapid, low-cost test.  相似文献   

12.
The parallel thinning algorithm with two subiterations is improved in this paper. By analyzing the notions of connected components and passes, a conclusion is drawn that the number of passes and the number of eight-connected components are equal. Then the expression of the number of eight-connected components is obtained which replaces the old one in the algorithm. And a reserving condition is proposed by experiments, which alleviates the excess deletion where a diagonal line and a beeline intersect. The experimental results demonstrate that the thinned curve is almost located in the middle of the original curve connectivelv with single pixel width and the processing speed is high.  相似文献   

13.
The relation between the power of the Brillouin signal and the strain is one of the bases of the distributed fiber sensors of temperature and strain. The coefficient of the Bfillouin gain can be changed by the temperature and the strain that will affect the power of the Brillouin scattering. The relation between the change of the Brillouin gain coefficient and the strain is thought to be linear by many researchers. However, it is not always linear based on the theoretical analysis and numerical simulation. Therefore, errors will be caused if the relation between the change of the Brillouin gain coefficient and the strain is regarded as to be linear approximately for measuring the temperature and the strain. For this reason, the influence of the parameters on the Brillouin gain coefficient is proposed through theoretical analysis and numerical simulation.  相似文献   

14.
Today, micro-system technology and the development of new MEMS (Micro-Electro-Mechanical Systems) are emerging rapidly. In order for this development to become a success in the long run, measurement systems have to ensure product quality. Most often, MEMS have to be tested by means of functionality or destructive tests. One reason for this is that there are no suitable systems or sensing probes available which can be used for the measurement of quasi inaccessible features like small holes or cavities. We present a measurement system that could be used for these kinds of measurements. The system combines a fiber optical, miniaturized sensing probe with low-coherence interferometry, so that absolute distance measurements with nanometer accuracy are possible.  相似文献   

15.
A new quantum protocol to teleport an arbitrary unknown N-qubit entangled state from a sender to a fixed receiver under M controllers(M < N) is proposed. The quantum resources required are M non-maximally entangled Greenberger-Home-Zeilinger (GHZ) state and N-M non-maximally entangled Einstein-Podolsky-Rosen (EPR) pairs. The sender performs N generalized Bell-state measurements on the 2N particles. Controllers take M single-particle measurement along x-axis, and the receiver needs to introduce one auxiliary two-level particle to extract quantum information probabilistically with the fidelity unit if controllers cooperate with it.  相似文献   

16.
A continuous-wave (CW) 457 nm blue laser operating at the power of 4.2 W is demonstrated by using a fiber coupled laser diode module pumped Nd: YVO4 and using LBO as the intra-cavity SHG crystal With the optimization of laser cavity and crystal parameters, the laser operates at a very high efficiency. When the pumping power is about 31 W, the output at 457nm reaches 4.2 W, and the optical to optical conversion efficiency is about 13.5% accordingly. The stability of the out putpower is better than 1.2% for 8 h continuously working.  相似文献   

17.
Call for Papers     
正Wireless Body-area Networks The last decade has witnessed the convergence of three giant worlds:electronics,computer science and telecommunications.The next decade should follow this convergence in most of our activities with the generalization of sensor networks.In particular with the progress in medicine,people live longer and the aging of population will push the development of wireless personal networks  相似文献   

18.
正Information Centric Networking Information-Centric Networking(ICN) is an emerging direction in Future Internet architecture research,gaining significant tractions among academia and industry.Aiming to replace the conventional host-to-host communication model by a data-centric model,ICN treats data content as the first  相似文献   

19.
20.
LI Shaoqian 《中国通信》2014,(6):I0001-I0002
The global bandwidth shortage of wireless communications has motivated the exploration of the naillimeter wave (ram-wave) frequency spectrum for the next generation wireless communications. Recent advances in RF CMOS technology and high speed baseband signal processing technologies have enabled tile extensive research and development of turn-wave wireless communications. The multi gigabit per second data rate of ram-wave system will lead to applications in many important scenarios, such as WPAN, WLAN,back-haul for cellular system. And the frequency bands include 28 GHz, 38 GHz, 45GHz, 60GHz, E-BAND and even beyond 100 GHz. The propagation and the imitation of the RF circuits design in these frequency bands make the directional antennas be inevitable for mm-wave communications.  相似文献   

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