Corrosion Inhibition Mechanism with Spilt Cell Technique of Rare Earth Metal on LC4 Al Alloy

A new method of studying the corrosion inhibition mechanism of rare earth metal(REM) on LC4 Al alloy with the spilt cell technique was studied. The principle and experimental method of the spilt cell technique were analyzed. By measuring the change of net-electric current between the two electrodes caused by the change of the amount of oxygen in the solution and the addition of CeCl₃, the influence of corrosive performance of CeCl₃ on LC4 super-power aluminum alloy in the 0.1 mol·L⁻¹ NaCl solution was investigated. Meanwhile, the conditional changes of pH values, CeCl₃ solution, additire and time of performance were also studied. Finally, the features of electrode surface were revealed by using SEM and X-ray energy-dispersive spectrometry (EDS). By combining these with other electric chemical techniques, such as potential-time curve, polarization curve et al.     

感应式电能表的智能化改进

介绍了利用AVR单片机AT90S8515的输入捕捉功能对感应式电能表进行智能化改进的方法，讨论了新型防盗电系统的结构原理，给出了用AT90S8515单片机设计带有防盗电功能的感应式电能袁的改进电路组成及工作过程。     

软件无线电中采样率转换技术的实现及在3G中的应用

目前移动通信标准繁多,且新旧体制混杂,很难做到统一.为了实现互连互通,目前比较可行的方法是采用软件无线电.采样率转换技术是实现互连互通的关键.文中针对第三代移动通信系统(3G)中不同通信体制的带宽、速率要求,根据分级变换的思想,对3G中的CDMA2000和TDSCDMA的采样率转换方案进行了设计,并对3G中的5种制式的采样率转换方案进行了分析比较.实验表明,这一方案可以在采样率变换的高效网络结构基础上进一步降低滤波运算量和存储量.     

反应器和钢烟囱整体吊装的难点和对策

介绍了在金陵石化炼油厂200万t/a柴油加氢装置建设中,将质量为237t的反应器和高60m的钢烟囱成功进行整体吊装过程中的关键技术.通过此项工程实践得出以下结论象钢烟囱这样细长重物的整体吊装,由两台吊车抬立起后,再由主吊车独立吊装就位的施工方法简单易行,安全可靠,应用范围广;结构复杂细长杆的吊装强度和挠度计算比较复杂,在计算过程中可以忽略部分次要件的质量,分别以两吊点为支点计算上下吊点所受的力,然后再按比例放余量,使两吊点受力之和等于细长杆的重力,计算挠度时,可以适当地把问题夸大化,从而建立近似的力学模型;高压厚壁重型容器的吊装,宜直接设置专门吊盖与大法兰用螺栓把紧起吊;施工现场地基坚实是保证吊车站位和吊装施工的前提条件.     

Wave propagation in two-phase flow of magnetic fluid under a nonuniform magnetic field

The effect of nonuniform magnetic field on the linear and nonlinear wave propagation phenomena in two-phase pipe flow of magnetic fluid is investigated theoretically to realize the effective energy conversion system using boiling two-phase flow of magnetic fluid. Firstly, the governing equations of two-phase flow based on the unsteady thermal nonequilibrium two-fluid model are presented and the linear void wave propagation phenomena in boiling two-phase flow are numerically analyzed by using the finite volume method. Next, the nonlinear pressure wave propagation in gas-liquid two-phase flow is numerically analyzed by using the finite different method. According to these theoretical studies on the wave propagation phenomena in two-phase flow of magnetic fluid, it seems to be a reasonable proposal that the precise control of the wave propagation in two-phase flow is possible by effective use of the magnetic force.     

A novel dynamic survivable routing in WDM optical networks with/without sparse wavelength conversion

In this paper, we study the dynamic survivable routing problem, both in optical networks without wavelength conversion and in optical networks with sparse wavelength conversion, and propose a novel hybrid algorithm for it based on the combination of mobile agents technique and genetic algorithms (GA). By keeping a suitable number of mobile agents in the network to cooperatively explore the network states and continuously report cycles (that are formed by two disjoint-link routes) into the routing tables, our new hybrid algorithm can promptly determine the first population of cycles for a new request based on the routing table of its source node, without the time consuming process associated with current GA-based lightpath protection schemes. We further improve the performance of our algorithm by introducing a more advanced fitness function that is suitable for both the above networks. Extensive simulation studies on the ns-2 network simulator show that our hybrid algorithm achieves a significantly lower blocking probability than the conventional survivable routing algorithms for all the cases we studied.     

新增探明储量的经济可采储量计算方法

提出了新增探明储量有无经济可采储量的判别方法。在此基础上，通过对立已开发油田技术可采储量经济转化率与油藏空气渗透率的相关关系式和图版，根据储层的空气渗透率，计算新增探明储量的经济转化率和经济可采储量。该方法参数易取，计算简便，对于快速、准确计算新增探明储量的经济可采储量具有重要意义。     

无差拍控制提高变速异步风力发电系统的故障承受能力

变速风力发电机对于电网扰动、故障以及电网电压跌落非常敏感，当上述情况发生时风力发电机将从电网切除，直到电网恢复正常才能重新投入运行。如何在电网发生扰动时保持风力发电机的正常运行是一个有挑战性的课题。未来的电网规范甚至要求在电网发生故障时风力机组仍能保持运行，这就要求必须安装保证风电机组低电压运行的控制装置。文中针对采用全载换流器与电网进行连接的异步风力发电机组提出了相应的风电机组低电压控制器及控制策略，无须进行硬件改造即可实现电网故障情况下风电机组不退出运行。其中，风电机组电气子系统控制器基于无差拍控制策略进行设计。算例给出了300 kW的风电机组在30%电压跌落情况下的暂态过程，没有加入控制器之前风电机组将停机，加入之后则可以保持运行，验证了所提方法的正确性。     

辽河催化裂化澄清油中间馏分热反应研究

采用先加入絮凝剂脱灰，再经减压蒸馏切割420～500℃馏分的方法，将辽河催化裂化澄清油预处理，考察了澄清油、加入絮凝剂脱灰后的澄清油以及脱灰后再减压蒸馏所得的中间馏分这3种原料在热转化过程中中间相的转化历程，并采用偏光显微镜观察热转化产物。结果表明，澄清油预处理效果明显，所得中间馏分具有较低的H／C原子比（nH／nC）和适宜的组成分布，是生产针状焦的理想原料。热转化产物的光学组织结构属于各向异性发达的广域-流线型结构。     

Analysis and Optimization of Noise in Bipolar RF Harmonic Mixers

A noise analysis of bipolar harmonic mixers (BHM) used for direct-conversion receivers is presented in this paper. Analytical and simulated results for the transfer function of the mixer are presented. Simple analytical expressions describing noise contribution from all sources are derived. Estimation of flicker noise quite agrees with harmonic-balance simulation results. Based on the derived expressions, total time average noise power spectral density (PSD) at the output is compared with simulation results. For the recommended regions of operation, error is less than 20%. The overall BHM noise figure (NF) is calculated and optimized based on a simple extracted formula. Errors introduced by analysis remain within a 1.5-dB margin with respect to simulation results. The validity of analysis for high frequencies is justified. The effect of flicker noise coefficient on the overall mixer NF is compared for different available processes.