Phase Equilibria of BaO-R2O3-CuO z Systems (R = Y and Lanthanides) under CO2-free Conditions

For applications ranging from phase equilibria to the processing of second-generation high T _c superconductor-coated-conductors, phase diagrams constructed under carbonate-free conditions are needed. Subsolidus phase equilibria of BaO-R₂O₃-CuO _z (R = Ho) have been investigated at (810°C), 21 kPa (875°C) and 0.1 MPa (850 and 930°C) by applying controlled atmosphere methods to minimize the presence of carbonate and CO₂ and H₂O contamination. Under carbonate-free conditions, most of these phase diagrams are different from those reported in the literature. In this paper, we also review and compare the phase diagrams of ten BaO-R₂O₃-CuO _z systems (R = Nd, Sm, Eu, Gd, Dy, Y, Ho, Er, Tm and Yb) that were previously determined in this laboratory under Among these diagrams, a distinct trend of phase formation and tie-line relationships is observed.     

雷达用磁控管自动老炼测试系统的设计

阐述了一种磁控管自动老炼测试系统的工作原理,介绍了其主要技术指标与系统组成,并给出了其软件的设计。该系统采用集中监控系统实现电源的监控以及磁控管性能数据的实时采集、显示和录取,提高了老炼测试效率和自动化水平。     

一种改进的粒子群算法在PCB板元件检测中的应用

为了满足实时图像检测对检测速度、成功率和抗噪性的较高要求,采用了粒子群算法,并增加了代间差分算子和全局收敛的随机算子,利用粒子群进化过程中隔代信息以及种群变异的机制,提高算法的成功率和抗噪性能。使用实时拍摄的PCB板元件图像进行仿真测试的实验表明,改进后的算法保持了更快的收敛速度,同时成功收敛率和抗噪性得到较大提高,能够适用在实际价值较高的PCB板检测现场。     

Fabrication of ZnO nanorod-based hydrogen gas nanosensor

We report a first work on nanofabrication of hydrogen nanosensor from single ZnO branched nanorods (tripod) using in-situ lift-out technique and performed in the chamber of focused ion beam (FIB) system. Self-assembled ZnO branched nanorod has been grown by a cost-effective and fast synthesis route using an aqueous solution method and rapid thermal processing. Their properties were analyzed by X-ray diffraction, scanning electron microscopy, energy dispersion X-ray spectroscopy, transmission electron microscopy, and micro-Raman spectroscopy. These analyses indicate high quality ZnO nanorods. Furthermore, our synthesis technique permits branched nanorods to be easily transferred to other substrates. This flexibility of substrate choice opens the possibility of using FIB system for handling.

The main advantage of the proposed in-situ approach is a controllable lift-out procedure which permitted us to obtain a 90% success rate for building nanodevices. The fabricated nanosensor uses only single self-assembled ZnO branched nanorod (tripod) to gauge the 150 ppm H₂ in the air at room temperature. The hydrogen sensitivity is in the range of 0.6–2% depending on which two branches to use. The nanosensor has selectivity against other gases such as O₂, CH₄, CO and LPG, which shows sensitivity of <0.02%. The single ZnO branched nanorod sensor can operate at low power of <5 μW.     

一种高速移动数据突发通信中的频偏纠正方法

本文主要针对具有通信终端的运动速率很大、移动速率变化不规律特点的特殊突发数据通信系统的实现进行研究，提出了一种能够快速捕获频偏，并且进行突发数据的有效解算的方法。这种方法需要采用差分相位调制方式，并且应用很短的前导序列进行频偏估计，然后利用估计得到的频偏对突发包内的数据进行处理和解调判决以获得传输的数据。同时文中在这种方法的基础上引入了正交的第二支路进行并行处理和择优选取，可以进一步提高系统的稳定性和实用性。该算法克服了传统频偏纠正算法具有有限纠正范围的缺点，具有良好的通信性能，并且实现简单，捕获速度快，信息冗余度也较小。     

催化剂组分对制取单壁碳纳米管的影响

采用温控电弧炉,以FeS,Ni,Mg的混和粉末作为催化剂,起弧电压为32V,放电时间为10min;研究了催化剂组成与成分对制取单壁碳纳米管的影响,确定了优化参数。在环境温度为600℃时,起弧电流为100A,催化剂FeS/Ni/Mg的组成和成分含量分别为2∶1∶2(%),5%,氦气气氛,气氛真空度为5.7×104Pa,单壁碳纳米管的产量和纯度都分别达到了12g/h和70%上,其管径为1.24～1.36nm。     

投影机新技术综述

投影机是高新科技发展的产物。本文介绍了近年来投影机上使用的新技术,包括投影机的核心显示技术,如亮度、色彩、对比度控制技术、个性化使用技术以及安全防护技术,为投影机产品的选购提供技术参考。     

改进缺陷,套刻和聚焦性能的第五世代浸没式曝光系统

论述了第五世代双扫描平台浸液式扫描曝光机的性能和进展。表明了在高速扫描状态下有生产价值的套刻和聚焦性能的实现。浸液式设备更多的关键部分与缺陷有关,而且该机的改进是通过有生产价值的缺陷水平方面来体现的。为了保持这种缺陷水平的改进效果,需要在圆片应用中进行专门稳定的测量。特加是边缘空泡除去(EBR)设计和圆片斜面良流线性是很重要的。     

MML方法在航空航天系统可靠性分析中的应用

修正的极大似然估计法是一种基于经典估计理论系统的可靠性分析方法中较优的算法。主要介绍MML方法及其在航空航天系统可靠性分析中的应用。     

基于MSP430F1611的自容式叶绿素仪的采集控制电路的低功耗设计

电池供电的自容式叶绿素仪需要在水下长期工作,系统平均功耗必须低,其主要功耗来自于采集控制电路,为满足自容式叶绿素仪的采集控制电路的功耗和处理能力要求,提出基于MSP430F1611的低功耗系统软硬件方案,并针对功耗和处理能力的矛盾,研究了MSP430F1611的主频与功耗之间的关系,通过实测和理论计算,提供了在特定任务条件下的采集控制电路的功耗优化方法.