14nm低原子序数材料多层膜的设计和制备

为了减小常规多层膜的带宽,提高其光谱分辨率,对采用低原子序数材料组成的适用于极紫外和软X射线波段的多层膜进行了研究.首先,在14 nm波长处选取3种低原子序数材料对Si/B4C,Si/C和Si/SiC组成多层膜,用随机搜索的方法优化设计了这3种多层膜以及在此波段常用的Mo/Si多层膜.然后,用直流磁控溅射的方法制备Si...     

X射线粉末衍射仪的新进展

介绍了Ｘ射线粉末衍射仪最新技术进展及今后的发展趋势。     

X射线衍射仪控制器的硬件设计

X射线衍射仪是利用X射线照射到不同的物质时,由于构成不同物质的晶体结构不同,就产生不同的衍射条纹,是一种研究晶体结构的分析方法,而不是研究样品内含有元素种类及含量的一种方法.X射线衍射仪数据控制器是X射线衍射仪的主要组成部分.     

玻璃结石的X射线衍射分析

结石是玻璃的一种严重缺陷,妨碍玻璃的透明性,也影响制品的外观,降低制品的使用价值。分析产生结石的原因,是消除这种缺陷的关键。本文利用X射线衍射仪对玻璃中的结石进行了晶相分析,结果表明,玻璃A中的结石主要为氧化铝（α-Al2O3）晶体、黄褐色、粒状、晶粒大、来源于耐火材料,玻璃B中的结石主要为方石英和磷石英（SiO2）晶体,白色,形状不规则,晶粒小,为玻璃熔体本身的析晶。这一发现为改进工艺,更新生产设备,消除玻璃缺陷提供了依据。     

国产X射线粉末衍射仪的现状

对国产X射线粉末衍射仪的现状进行了评述。近年国产粉末衍射仪较之以前已有很大的进步。虽与进口仪器仍有差距,但国产仪器已可满足粉末结构分析和物相分析的基本需要。现在无论应用国产衍射仪还是进口知名衍射仪,在相近的实验条件下,得到的X射线粉末衍射图数据的质量是同一水平的。     

多晶X射线衍射仪的技术进展

简要介绍了近几年来多晶X射线衍射仪的光源、测角仪、样品台、光学系统、附件、检测器和应用软件方面的技术进展和用途扩展情况。     

X射线衍射仪数据控制器主控模块设计

X射线衍射仪数据控制器噪用了多CPU总线系统集成技术，是一个多CPU系统控制器，每个CPU控制一个模块，每一个模块都是一个独立的计算机系统，各个系统之间靠底板上的总线连接在一起。     

X射线衍射仪的微机数据处理系统

本文介绍的X射线衍射仪微机数据处理系统,用先进的微机技术对我国早年进口的日本理学3015X射线衍射仪进行改造。在仪器原有的测量控制下,通过简单的接口,将衍射仪及附机X荧光分析仪的测量数据准确地采集到微型计算机中,由微机来完成X衍射及X荧光分析中的各种繁琐而又重复的数据处理任务,将仪器的分析性能提高到一个新的水平。本文着重介绍微机与3015X衍射仪的硬件联接和测量数据的采集。     

用光腔衰荡法测量高反射率的实验研究

根据光腔衰荡光谱技术开展了测量镜片高反射率的研究,建立了测量实验装置。理论上给出了反射率测量的计算方法,在实验中测定了一对反射率相等的高反射腔镜的反射率,以及一块45°反射镜样品的反射率,并分析了影响光腔衰荡曲线的参数。     

用光腔衰荡法测量高反射率的重复性测试

根据光腔衰荡光谱技术开展了测量镜片高反射率的研究,建立了测量实验装置,理论上给出了反射率测量的计算方法,在实验中测定了一对反射率相等的高反射腔镜的反射率,以及一块22.5°反射镜样品的反射率,所得反射率的标准偏差好于10-5。该仪器具有较高的实验重复性。     

吸波材料反射率变温测试系统研制

通过对常用的反射率测试方法进行比较,针对目前存在的问题,搭建了一套新型的电磁波吸波材料反射率变温测试系统.该系统以弓形法为基础,对其结构进行了改进,舍弃了架设在被测材料上方的弓形支架,用铝型材搭建了天线转臂,该结构有效的减少了弓形支架的散射波对测试结果的影响,提高了测试精度.为实现高温下反射率的测试,研制了变温测试平台,该系统能够在2～40 GHz的频率范围内实现室温到800℃的吸波材料反射率测试,通过对一些材料进行不同角度和不同温度下的反射率测试,验证了该系统的可靠性.     

Plasmon transmissivity and reflectivity of narrow grooves in a silver film

Surface plasmon (SP) reflectivity and transmissivity of narrow grooves in silver films are studied. The SP source is the probe of a scanning near-field optical microscope. Locally detected leakage radiation from the SP provides detailed information on the paths of SP propagation, in particular the influence of perturbations. Global detection provides representative average data on the SP properties of a given metal film and its structures. A groove of 200 nm width, for instance, reflects/transmits about 15%/80% of 'blue–green' SP radiation at normal incidence.     

Thin layer activation for measuring fretting wear and material transfer in iron alloys

An important difference between fretting wear and macroscopic wear processes lies in the amounts of wear volume. Because of the small relative displacements in fretting wear the wear volumes are much smaller than in (classical) macroscopic wear processes. Classical wear measuring techniques such as weighing and 2D-profilometry often fail to determine the fretting wear volumes. Their sensitivity as well as their accuracy are inadequate. 3D-profilometry partially solves this problem but the obtained wear results do not take eventual material transfer between the test specimens into account. In this work thin layer activation (TLA) is presented as a potentially powerful tool for quantitative fretting studies, especially in relation to material transfer. In contrast with the other mentioned wear measuring technique TLA allows measurements of very small amounts of wear as well as material transfer between the test specimens. Preliminary results are reported for steel specimens. A surface zone of 7 mm² of one test specimen, in which the wearing zone during the fretting experiment is situated, is irradiated with protons from a cyclotron. As a result of a nuclear reaction the iron in the irradiated test specimen forms radionuclides, mainly cobalt-56, in a surface layer of 260 μm depth. The amount of cobalt-56 as compared to iron is negligible so that the physical and chemical properties of the irradiated zone remain unaffected. Measuring the gamma rays of cobalt-56 in the wear debris gives quantitative information about the wear volume and measuring the mating surface gives information on the transfer volume.     

软X射线共振反射方法表征Sc/Si多层膜界面化合物成分的计算研究

Sc/Si周期多层膜是极紫外波段的重要材料,但膜层界面处材料原子间的扩散与化合反应严重影响了多层膜反射率。为了无损表征多层膜界面化合物的成分,利用软X射线共振反射的方法,研究了Sc/Si多层膜界面化合物成分。在Si的L吸收边附近,计算了不同周期厚度以及不同界面硅化物成分的Sc/Si多层膜的共振反射率。结果表明,界面硅化物成分不同的膜系在Si的L边处的反射率有明显差异,并且反射率随着膜层中Si化合反应的消耗而降低,证实了软X射线共振反射方法在亚纳米尺度下对化合物的成分进行无损分析的可行性,为后续的实验研究提供参考。     

Characterization of nitride thin films by electron backscatter diffraction

Thin films incorporating GaN, InGaN and AlGaN are presently arousing considerable excitement because of their suitability for UV and visible light‐emitting diodes and laser diodes. However, because of the lattice mismatch between presently used substrates and epitaxial nitride thin films, the films are of variable quality. In this paper we describe our preliminary studies of nitride thin films using electron backscattered diffraction (EBSD). We show that the EBSD technique may be used to reveal the relative orientation of an epitaxial thin film with respect to its substrate (a 90° rotation between a GaN epitaxial thin film and its sapphire substrate is observed) and to determine its tilt (a GaN thin film was found to be tilted by 13 ± 1° towards [101 0]_GaN), where the tilt is due to the inclination of the sapphire substrate (cut off‐axis by 10° from (0001)_sapphire towards (101 0)_sapphire). We compare EBSD patterns obtained from As‐doped GaN films grown by plasma‐assisted molecular beam epitaxy (PA‐MBE) with low and high As₄ flux, respectively. Higher As₄ flux results in sharper, better defined patterns, this observation is consistent with the improved surface morphology observed in AFM studies. Finally, we show that more detail can be discerned in EBSD patterns from GaN thin films when samples are cooled.     

基于嵌入式技术和轮计量的原料入库确认系统的开发

本文集成应用嵌入式计算机,配合塞销式传感器和双向高速AD模块,通过轮计量、车号识别系统及两者之间的时间关系,完成无约束动态判车,详细记录列车出入库房情况,确认原料入库。     

Flow rate measurement in flows with asymmetric velocity profiles by means of distributed thermal anemometry

Flow rate in closed conduits is one of the most frequently measured parameters in industrial processes and in gas and water supply. For an accurate measurement, flow meters typically require a fully developed symmetric flow profile with preferably no radial or tangential velocity components. This is commonly secured by mounting flow meters in a pipe at a sufficiently long distance downstream any change in cross-section or pipe direction. In this paper, we introduce a new approach for flow rate measurement of gases or liquids that employs a novel spatially resolving fluid velocity sensor basing on thermal anemometry. The new principle allows accurate flow rate measurements for non-axisymmetric velocity profiles, even directly after pipe bends, T-junctions or other alterations in the pipe geometry. This is exemplified for air flow in three different pipe bend configurations.     

液态物料定量灌装机计量标准装置测量不确定度的评定及验证

本文介绍了液态物料定量灌装机计量标准的测量不确定度评定及测量不确定度的验证.仅供参考.