YAlO3∶Eu3+发光纳米纤维的制备与表征

采用静电纺丝技术制备了聚乙烯吡咯烷酮PVP/[Y(NO3)3+Al(NO3)3+Eu(NO3)3]复合纤维,将其进行热处理,得到了YAlO3:Eu3+发光纳米纤维。采用X射线衍射(XRD)、扫描电镜(SEM)、荧光光谱等技术对样品进行了表征。PVP/[Y(NO3)3+Al(NO3)3+Eu(NO3)3]复合纤维经1200℃焙烧2h后,获得了YAlO3:Eu3+纳米纤维,属于正交晶系,空间群为Pnma。用Shapiro-Wilk方法检验了纤维直径分布情况,在95%的置信度下,纤维直径属于正态分布。PVP/[Y(NO3)3+Al(NO3)3+Eu(NO3)3]复合纤维表面光滑,纤维分散性较好,有很好的长径比,尺寸均一,平均直径为(152.9±26.0)nm;YAlO3:Eu3+纳米纤维的平均直径为(106.7±20.2)nm。在234nm的紫外光激发下,YAlO3:Eu3+纳米纤维的主要发射峰位于590nm和609nm处,分别属于Eu3+的5 D0→7F1跃迁和5 D0→7F2跃迁,Eu3+掺杂离子浓度对YAlO3:Eu3+发射峰的峰型与位置均没有影响,当Eu3+掺杂离子浓度为5%时,YAlO3:Eu3+纳米纤维发光最强。     

Nd3+:YAG发光纳米纤维的制备与表征

采用静电纺丝技术制备了PVP/[Y(NO3)3+Al(NO3)3+Nd(NO3)3]复合纳米纤维,将其进行热处理,获得了Nd3+:YAG发光纳米纤维.X射线衍射(XRD)分析表明,该复合纳米纤维为非晶态,经900℃焙烧10 h后,获得了单相石榴石型的Nd3+:YAG纳米纤维.扫描电子显微镜(SEM)分析表明,经过900℃焙烧后,获得了直径约75 nm的Nd3+:YAG纳米纤维,长度大于100μm.热分析(TG-DTA)表明,当焙烧温度高于550℃时,该复合纳米纤维中二甲基甲酰胺(DMF)、有机物和硝酸盐分解挥发完毕,样品不再失重,总失重率为84.7%.傅里叶变换红外光谱(FTIR)分析表明,当焙烧温度为900℃时,生成了Nd3+:YAG发光纳米纤维.对Nd3+:YAG纳米纤维的发光性质进行了研究,对Nd3+:YAG发光纳米纤维的形成机理进行了讨论.该技术可以用来制备其他稀土石榴石型化合物纳米纤维.     

静电纺丝制备复合纳米纤维研究进展

静电纺丝技术近年来在制备纳米纤维领域得到广泛应用,目前已成功制备出多种不同类型的纳米纤维,尤其在制备复合纳米纤维方面取得了显著成果,被认为是制备纳米纤维最有效的方法之一。总结了静电纺丝技术制备纳米纤维,特别是制备复合型纳米纤维方面的最新研究报道,如天然高分子复合纳米纤维、聚合物复合碳纳米管纤维、聚合物复合金属纳米纤维、共聚物纳米纤维以及无机复合纳米纤维等。静电纺丝纳米纤维将在生物医药、电子光学、制备复合材料等多个领域得到广泛应用。     

静电纺丝技术制备光学功能纳米纤维

介绍了静电纺丝制备纳米纤维的基本原理、装置及运用静电纺丝技术制备的实芯、空芯、多孔和带状等几种不同结构的纳米纤维,阐述了近年来同内外研究者通过静电纺丝技术制备出的发光纳米纤维以及光学偏振纳米纤维的相关成果及研究进展,并讨论了这类光学功能纳米纤维潜在的应用.     

同轴电纺制备纳米纤维影响因素的研究进展

同轴静电纺丝技术制备的核-壳复合结构纳米纤维已取得了显著成果,在众多领域都具有较大的应用价值。通过对传统静电纺丝和同轴静电纺丝进行比较,分析了同轴静电纺丝的特点,并指出复合泰勒锥体和喷射流的稳定性直接影响着复合纳米纤维的形貌。重点讨论了纺丝过程中诸如黏度、浓度、电纺性、溶剂挥发性等溶液参数和流速、电压等工艺参数对核-壳结构纳米纤维形貌的影响作用,并探讨了流速对纤维成丝性的影响。最后归纳了核-壳结构纳米纤维在能源、组织工程、传感器等领域的优势和潜在应用。     

毛刷状ZnO@PVDF复合纳米纤维柔性压电纳米发电机

采用静电纺丝技术并通过两步低温水热法制备了“毛刷”状的氧化锌(ZnO)@聚偏二氟乙烯(PVDF)复合纳米纤维膜。结果表明，氧化锌纳米棒(ZnO NRs)均匀地径向生长在PVDF纳米纤维的表面，FTIR分析发现ZnO@PVDF复合纳米纤维膜β相含量相比PVDF纳米纤维膜从72.3%提升到85.6%,增加了18.4%。ZnO@PVDF复合压电纳米发电机(PENG)输出电压可达4.9 V,短路电流为293 nA。在外部负载电阻达到13 MΩ时，ZnO@PVDF复合PENG达到最大输出功率0.93μW。ZnO@PVDF复合PENG可以为电容器充电，电容放电时成功点亮LED小灯泡。此外，在5000次的循环敲击测试中，ZnO@PVDF复合PENG具有稳定的输出电压，有望作为无源设备的自供电电源得到广泛应用。     

电纺SnO_2纳米纤维的制备及其气敏特性

采用聚乙烯醇(PVA,Mw=80000g/mol)和五水合四氯化锡(SnCl4.5H2O)作为静电纺丝前驱液,着重研究了纺丝电压、前驱液中PVA浓度及煅烧温度等因素对纺丝过程及纤维特性的影响,并用扫描电镜(SEM)和X射线衍射(XRD)等分析手段对纤维的微观结构、表面形貌和结晶状态进行了表征。结果表明,当纺丝电压为4kV、纺丝液中PVA质量分数为7%、退火温度为700℃时,可以得到平均直径为300nm的连续SnO2纳米纤维。该纤维对乙醇的响应恢复时间小于15s,检测极限低于10×10-9。     

ZnS∶Mn/PVA复合纳米纤维的制备及性能分析

采用绿色化学方法、通过使用对环境友好无危害的橄榄油,结合静电纺丝技术,成功制备了ZnS∶Mn/PVA复合纳米纤维。通过扫描电镜和X射线衍射对复合纳米纤维结构进行表征,通过光致发光研究了复合纳米纤维的光学性质。扫描电镜结果表明ZnS∶Mn/PVA复合纳米纤维的直径约为300 nm,X射线衍射仪结果显示ZnS∶Mn/PVA复合纳米纤维具有ZnS立方闪锌矿结构。光致发光光谱表明ZnS∶Mn/PVA复合纳米纤维在590 nm处具有较强的尖锐发射峰,实现了Mn2+的特征发射。ZnS∶Mn/PVA复合纳米材料是一种非常好的发光材料,有望在光电领域得到应用。     

基于电纺纤维的CuO/SnO_2薄膜及其气敏特性

研究了一种基于静电纺丝纳米纤维制备异质结薄膜的方法。采用静电纺丝技术在硅衬底上依次沉积PVP/CuCl2.2H2O和PVP/SnCl4.5H2O纳米纤维,经过氧等离子体刻蚀并高温退火处理后得到了基于多孔纳米纤维的CuO/SnO2异质结薄膜。利用扫描电子显微镜(SEM)和X射线衍射技术(XRD)对纤维的形貌和结晶状态进行了表征。电学特性及气敏特性测试结果表明,该异质结薄膜具有明显的整流特性,在100℃的工作温度下,对H2S气体响应和恢复速度快、检测限低、选择性好。     

电纺掩模制备铜纳米线网络透明电极

通过真空蒸镀技术、静电纺丝技术和湿法腐蚀法成功制备出铜纳米线网络透明电极.首先优化纺丝条件,制备出均匀的聚丙烯腈(PAN)纳米纤维,然后将PAN纳米纤维作为掩模腐蚀铜膜得到铜纳米线网络透明电极.通过对纺丝时间、纺丝接收取向、蒸气处理时间和湿法腐蚀时间等制备条件进行优化,得到表面光滑连续、形貌良好的铜纳米线网络透明电极....     

Resolution Enhancement Technology:Integrated Process Solutions using OPC

DUV lithography, using the 248 nm wavelength, is a viable manufacturing option for devices with features at 130 nm and less. Given the low kl value of the lithography, integrated process development is a necessary method for achieving acceptable process latitude. The application of assist features for rule based OPC requires the simultaneous optimization of the mask, illumination optics and the resist.Described in this paper are the details involved in optimizing each of these aspects for line and space imaging.A reference pitch is first chosen to determine how the optics will be set. The ideal sigma setting is determined by a simple geometrically derived expression. The inner and outer machine settings are determined, in turn,with the simulation of a figure of merit. The maximum value of the response surface of this FOM occurs at the optimal sigma settings. Experimental confirmation of this is shown in the paper.Assist features are used to modify the aerial image of the more isolated images on the mask. The effect that the diffraction of the scattering bars (SBs) has on the image intensity distribution is explained. Rules for determining the size and placement of SBs are also given.Resist is optimized for use with off-axis illumination and assist features. A general explanation of the material' s effect is discussed along with the affect on the through-pitch bias. The paper culminates with the showing of the lithographic results from the fully optimized system.     

Cost-effective test solutions for smart card and other integrated flash applications

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.     

Theoretical analysis of the relationship between the Brillouin gain coefficient and the strain in the optical-fiber sensors

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.     

An improved parallel thinning algorithm with two subiterations

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.     

Novel fiber-optical interferometer with miniaturized probe for in-hole measurements

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.     

Development of the readout system for waveguide multilayer optical card

Waveguide multilayer optical card （WMOC） is a novel storage device of three-dimensional optical information. An advanced readout system fitting for the WMOC is introduced in this paper. The hardware mainly consists of the light source for reading, WMOC, motorized stages addressing unit, microscope imaging unit, CCD detecting unit and PC controlling ＆ processing unit. The movement of the precision motorized stage is controlled by the computer through Visual Basic （VB） language in software. A control panel is also designed to get the layer address and the page address through which the position of the motorized stages can be changed. The WMOC readout system is easy to manage and the readout result is directly displayed on computer monitor.     

Study of waveguide coupling efficiency in hybrid silicon lasers

This paper presents a new method to increase the waveguide coupling efficiency in hybrid silicon lasers. We find that the propagation constant of the InGaAsP emitting layer can be equal to that of the Si resonant layer through improving the design size of the InP waveguide. The coupling power achieves 42% of the total power in the hybrid lasers when the thickness of the bonding layer is 100 nm. Our result is very close to 50% of the total power reported by Intel when the thickness of the thin bonding layer is less than 5 nm. Therefore, our invariable coupling power technique is simpler than Intel＇s.     

Collinear phase-matching study of terahertz-wave generation via difference frequency mixed in GaAs and Inp

The collinearly phase-matching condition of terahertz-wave generation via difference frequency mixed in GaAs and InP is theoretically studied. In collinear phase-matching, the optimum phase-matching wave hands of these two crystals are calculated. The optimum phase-matching wave bands in GaAs and lnP are 0.95-1.38μm and 0.7-0.96μm respectively. The influence of the wavelength choice of the pump wave on the coherent length in THz-wave tuning is also discussed. The influence of the temperature alteration on the phase-matching and the temperature tuning properties in GaAs crystal are calculated and analyzed. It can serve for the following experiments as a theoretical evidence and a reference as well.     

Effects of the alloy compositions on the phonon-polaritons in ternary mixed crystals

Composition dependence of bulk and surface phonon-polaritons in ternary mixed crystals are studied in the framework of the modified random-element-isodisplacement model and the Bom-Huang approximation. The numerical results for Several Ⅱ - Ⅵ and Ⅲ- Ⅴ compound systems are performed, and the polariton frequencies as functions of the compositions for ternary mixed crystals AlxGa1-xAs, GaPxAS1-x, ZnSxSe1-x, GaAsxSb1-x, GaxIn1-xP, and ZnxCd1-xS as examples are given and discussed. The results show that the dependence of the energies of two branches of bulk phonon-polaritons which have phonon-like characteristics, and surface phonon-polaritons on the compositions of ternary mixed crystals are nonlinear and different from those of the corresponding binary systems.     

New insert layer structure OLEDs

An insert layer structure organic electroluminescent device（OLED） based on a new luminescent material （Zn（salen）） is fabricated. The configuration of the device is ITO/CuPc/NPD/Zn（salen）/Liq/LiF/A1/CuPc/NPD/Zn（salen）/Liq/LiF/A1. Effective insert electrode layers comprising LiF（1nm）/Al（5 nm） are used as a single semitransparent mirror, and bilayer cathode LiF（1 nm）/A1（100 nm） is used as a reflecting mirror. The two mirrors form a Fabry-Perot microcavity and two emissive units. The maximum brightness and luminous efficiency reach 674 cd/m^2 and 2.652 cd/A, respectively, which are 2.1 and 3.7 times higher than the conventional device, respectively. The superior brightness and luminous efficiency over conventional single-unit devices are attributed to microcavity effect.