High-resolution FIB-TEM-STEM structural characterization of grain boundaries in the high dielectric constant perovskite CaCu3Ti4O12

In this work, the grain boundaries composition of the polycrystalline CaCu₃Ti₄O₁₂ (CCTO) was investigated. A Focused Ion Beam (FIB)/lift-out technique was used to prepare site-specific thin samples of the grain boundaries interface of CCTO ceramics. Scanning transmission electron microscopy (STEM) coupled with energy dispersive X-ray spectrometry (EDXS) and Electron Energy Loss Spectroscopy (EELS) systems were used to characterize the composition and nanostructure of the grain and grain boundaries region. It is known that during conventional sintering, discontinuous grain growth occurs and a Cu-rich phase appears at grain boundaries. This Cu-rich phase may affect the final dielectric properties of CCTO but its structure and chemical composition remained unknown. For the first time, this high-resolution FIB-TEM-STEM study of CCTO interfacial region highlights the composition of the phases segregated at grain boundaries namely CuO, Cu₂O and the metastable phase Cu₃TiO_4.     

大水深测量校正方法研究与应用

水库水深测量精度直接关系到水库的防洪安全与蓄水兴利。现有回声测深仪无法应对大水深施测的情况，且测量受到水库水温分层影响。利用回声测深仪配合校正标进行大水深测量的校正方法，能够精确检测到回声测深仪水深测量的误差及差值、系统延时问题等，通过与各级校正标的真值比较、修正，能使测值近似真值,且使误差控制在容许范围内。介绍了水深校正标基本原理、操作方法和步骤以及在水库测深中的应用。     

Starch: a potential substrate for biohydrogen production

Hydrogen is a clean energy carrier with great potential to be an alternative fuel. Anaerobic hydrogen fermentation seems to be more favorable, since hydrogen is yielded at high rates and various organic waste and wastewater enriched with carbohydrates as substrate result in low cost for hydrogen production. Abundant biomass from various industries could be a source for biohydrogen production where combination of waste treatment and energy production would be an advantage. Carbohydrate‐rich nitrogen‐deficient solid wastes such as starch residues can be used for hydrogen production by using suitable bioprocess technologies. Alternatively, converting biomass into gaseous fuels, such as biohydrogen, is possibly the most efficient way to use these agroindustrial residues. This review summarizes the potential of starch agroindustrial residues as a substrate for biohydrogen production. Types of potential starch agroindustrial residues, recent developments and bio‐processing conditions for biohydrogen production will be discussed. Copyright © 2014 John Wiley & Sons, Ltd.     

LW-601喷水织机长丝织物松紧档疵点的成因及对策

松紧档疵点是喷水织机长丝织物织造过程中常见病疵之一。通过分析LW -60 1喷水织机的送经和卷取装置的工作原理 ,从机械调整与维护、生产过程管理及工艺优化等方面探讨了其产生的原因 ,并针对性提出了实用对策     

浅析6063铝型材表面“铝丝印”的成因与对策

在介绍“铝丝印”概念的基础上，从金属腐蚀学的观点出发，分析了“铝丝印”形成的电化学腐蚀机理，并提出了具体的解决措施。     

From Long Infrared to Very Long Infrared Wavelength Focal Plane Arrays Made with HgCdTe n + n ?/ p Ion Implantation Technology

This paper aims at studying the feasibility of very long infrared wavelength (VLWIR) (12–18 μm) focal plane arrays using n-on-p planar ion-implanted technology. To explore and analyze the feasibility of such VLWIR detectors, a set of four Cd _x Hg_1−x Te LPE layers with an 18 μ cutoff at 50 K has been processed at Defir (LETI/LIR–Sofradir joint laboratory), using both our “standard” n-on-p process and our improved low dark current process. Several 320 × 256 arrays, 30-μm pitch, have been hybridized on standard Sofradir readout circuits and tested. Small dimension test arrays characterization is also presented. Measured photonic currents with a 20°C black body suggest an internal quantum efficiency above 50%. Typical I(V) curves and thermal evolution of the saturation current are discussed, showing that standard photodiodes remain diffusion limited at low biases for temperatures down to 30 K. Moreover, the dark current gain brought by the improved process is clearly visible for temperatures higher than 40 K. Noise measurements are also discussed showing that a very large majority of detectors appeared background limited under usual illumination and biases. In our opinion, such results demonstrate the feasibility of high-performance complex focal plane arrays in the VLWIR range at medium term.     

延长分米波电视发射管使用寿命的探讨（上）

文章从原理上讨论了影响分米波电视发射管寿命的若干因素。并提出了若干延长寿命的建议：（１）正确的灯丝加热方法是行之有效的措施，经验证明：过分强调降低灯丝电压往往得到相反的效果。（２）必须有良好的冷却方式。（３）通过对帘栅电路的分析，说明对此电路必须作很好的处理以消除故障和防止寄生振荡。     

YAG激光打标机光笔中会聚出纤光的光学系统

智能化大幅面激光打标机中的光笔,采用本文叙述的光学系统会聚多模石英光纤出射的大功率YAG激光,通常能以小于0.2mm的线宽长时间连续地在工件上刻划,仔细调焦后线宽达0.1mm;手持此光笔可进行人工刻写、画及焊接电子元件等.     

面阵列封装器件的贴装技术

面阵列封装器件在电子产品中的使用率逐年上升，如何实现其高速贴装是影响生产线效率的重要因素。从不同的角度论述了面阵列封装器件实现高速贴装的手段与技术。     

招远金矿集中区金矿富集规律及找矿标志

招远金矿集中区是我国最大的金矿集中区，区内金矿床在时间和空间上的分布规律十分明显。该区矿化类型主要有石英脉型、蚀变岩型及二者之间的过渡类型，其在空间上的分布规律为综合信息找矿及矿床定位预测提供地质信息，并可作为进一步的找矿标志。