Enhancement of optical and electrical properties of SILAR deposited ZnO thin films through fluorine doping and vacuum annealing for photovoltaic applications

Undoped and fluorine doped ZnO thin films were deposited onto glass substrates using successive ionic layer adsorption and reaction (SILAR) technique and then annealed at 350 °C in vacuum ambience. The F doping level was varied from 0 to 15 at% in steps of 5 at%. The XRD analysis showed that all the films are polycrystalline with hexagonal wurtzite structure and preferentially oriented along the (002) plane. Crystallite sizes were found to increase when 5 at% of F is doped and then decreased with further doping. It was seen from the SEM images that the doping causes remarkable changes in the surface morphology and the annealing treatment results in well-defined grains with an improvement in the grain size irrespective of doping level. All the films exhibit good transparency (>70%) after vacuum annealing. Electrical resistivity of the film was found to be minimum (1.32×10⁻³ Ω cm) when the fluorine doping level was 5 at%.     

Flow pattern identification and measurement techniques in gas-liquid-liquid three-phase flow: A review

The simultaneous flow of gas, oil, and water forms various flow patterns due to the complex interfacial relationships. Three-phase flow patterns are classified as the gas-liquid and liquid-liquid flow patterns. Pressure drop, void fraction, liquid holdup, and phase distribution are important characteristics of the three-phase flow. These characteristics are generally associated with the three-phase flow patterns. Hence, the knowledge about flow patterns can help to predict the overall behavior of the three-phase flow. Studies have been conducted to identify three-phase flow pattern and their characteristics at various superficial velocities of gas, oil, and water. The major purpose of the studies is to gather information about the three-phase co-current flow and use it for improvement of the efficiency of the flow systems. Therefore, the accuracy of the measurement technique is critical. Several types of flow pattern identification and measurement techniques have been developed to improve accuracy and provide high-quality results. In this article, classical and advanced techniques used for the three-phase flow identification and measurement have been reviewed. The survey will help the researchers working in the area of multiphase flow to choose the right technique based on the objectives of the studies.     

盐卤除硝工艺的研究

介绍了一种采用氨碱蒸馏废液兑卤水进行除硝的新工艺 ,通过中试确定了该工艺的主要技术参数 ,为工程设计提供了条件。     

移动通信系统中功率控制研究

在阐述功率控制在移动通信系统中的发展过程的基础上，着重研究了WCDMA系统的功率控制，最后对功率控制未来的研究方向做了简要的分析。     

天然气水合物和天然气脱水新工艺探讨

探讨了天然气水合物的发展过程、形成条件以及对天然气输送管道的腐蚀堵塞作用,对我国天然气脱水创新技术———膜法脱水、汽提脱水的原理与工艺过程进行了全面论述。考察了气体处理量及操作压力等对我国1.2×105m3/d天然气膜法脱水的工业试验装置的脱水过程的影响。     

自动监视和告警系统中红外弱小目标的识别

红外弱小目标识别一直是自动监视和告警系统中的一项关键技术。成像跟踪识别系统的算法研究需要分析特定应用环境中的背景和目标特点，本文第一部分对此进行了分析。接下来，在对应用环境进行分析的基础上，对远距离红外小目标的探测、识别和跟踪算法进行了介绍。最后，针对视频环境下的红外跟踪，介绍了为提高跟踪稳定性而进行的一系列实验及其原理装置。     

全光网中的光信噪比估算与系统设计

指出了WDM光传送网中 ,级联光上下路节点或光交叉连接节点后 ,系统构成上与传统级联线路放大器情况下的差异以及常用光信噪比评估公式的近似性。对WDM光传送网中线路给出了一个等效模型 ,并详细推导了光信噪比的计算公式 ,同时计入了光放大器的自发辐射噪声引起的饱和效应。最后针对不同系统配置情况进行了光信噪比的估算 ,分析了估算结果及其对线路设计的指导意义     

随机减量技术中周期激励的影响及消除方法

本文针对机械系统中通常存在确定性周期激励的事实 ,论证了周期干扰成分的存在对提取的随机减量特征信号的影响 ,基于数字滤波技术提出了一种从周期干扰环境中提取随机减量特征信号的简便方法。在回转机械稳定性监测中的应用实例表明本文提出的方法是有效的。     

油气储层敏感性伤害机理识别方法及应用实例

从油气储层岩石学分析入手,阐述了砂岩储层4类敏感性发生的原因及作用机理,结合几个实例,论述了油气开发实践中,必须针对砂岩储层的非均质性特点,对症下药,在充分掌握储层伤害机理的基础上,研制保护与改造油气层的措施,才能取得实效。本文的研究方法可为陆相复式油气区同类砂岩储集层的勘探、开发提供借鉴。     

有限元技术在数值试井中的应用

分析了试井技术的发展趋势，对有限元分析技术及其发展作了较为全面的介绍，重点阐述了利用有限元技术进行三维建模的方法和步骤，尤其是对复杂的非对称边界和非均质油藏的建模方法和技巧进行了深入探讨。利用数值试井技术，石油工程师可以方便准确地对复杂油藏和边界进行建模，试井的模拟过程和油藏任意位置的压力瞬间变化都可以通过图形和颜色的变化显示出来，解释的精度和速度都得到了大大地提高。