阿鸠田电站SF35-16/4100水轮发电机绝缘工艺

云南保山阿鸠田电站由三台SF35-16/4100水轮发电机组成,单机额定容量35 MW,额定电压10.5 kV,定、转子绕组均采用F级绝缘。根据用户要求采用了一些新绝缘结构,并进行了大量的工艺试验,生产中选择优质材料,严格控制工艺过程,使已出厂的三台发电机定、转子线圈及定、转子装配的电气绝缘性能优良。文章就机组定、转子绕组绝缘工艺进行了简要的介绍。     

Understanding silica-supported metal catalysts: Pd/silica as a case study

Supported metal catalysts, particularly noble metals supported on SiO₂, have attracted considerable attention due to the importance of the silica–metal interface in heterogeneous catalysis and in electronic device fabrication. Several important issues, e.g., the stability of the metal–oxide interface at working temperatures and pressures, are not well-understood. In this review, the present status of our understanding of the metal–silica interface is reviewed. Recent results of model studies in our laboratories on Pd/SiO₂/Mo(1 1 2) using LEED, AES and STM are reported. In this work, epitaxial, ultrathin, well-ordered SiO₂ films were grown on a Mo(1 1 2) substrate to circumvent complications that frequently arise from the silica–silicon interface present in silica thin films grown on silicon.     

A new detection algorithm (NDA) based on fuzzy cellular neural networks for white blood cell detection.

White blood cell detection is one of the most basic and key steps in the automatic recognition system of white blood cells in microscopic blood images. Its accuracy and stability greatly affect the operating speed and recognition accuracy of the whole system. But there are only a few methods available for cell detection or segmentation due to the complexity of the microscopic images. This paper focuses on this issue. Based on the detailed analysis of the existing two methods--threshold segmentation followed by mathematical morphology (TSMM), and the fuzzy logic method--a new detection algorithm (NDA) based on fuzzy cellular neural networks is proposed. NDA combines the advantages of TSMM and the fuzzy logic method, and overcomes their drawbacks. With NDA, we can detect almost all white blood cells, and the contour of each detected cell is nearly complete. Its adaptability is strong and the running speed is expected to be comparatively high due to the easy hardware implementation of FCN. Experimental results show good performance.     

基于CB的串行口和接口板端口程序应用

串行口及接口板端口是计算机通信的主要途径 ,也是目前计算机工程测控中通用的基本方法。C Builder (简称CB)编程语言以其功能完备、开发效率高的特点而成为目前流行的程序开发工具 ,介绍了利用CB语言编写串行口和端口通信的程序的方法 ,并对具体的各方法编写了相应的示例。     

原油基压裂液研究

研制了一种适用于低压、低渗、水敏性储集层的新型原油基压裂液体系。根据基液原油的组分合成相应的增稠剂，增稠剂在原油中与交联剂反应，形成网状结构，使原油成为黏度可以调控的冻胶，从根本上改变了油基压裂液以柴油、煤油为基液的现状，降低了油基压裂液的成本，同时还提高了压裂液的抗温、抗剪切和破胶性能，并将交联时间缩短到2h以内，可以满足现场压裂施工的要求，大大降低了施工强度和压裂改造的综合成本。在青海油田进行的现场先导试验取得成功。图9表1参5     

三网互联的几个关键技术

对三网互联的几个关键技术进行分析与研究，介绍利用IP技术解决有线电视网地址选择问题，探讨怎样将ATM技术与IP技术相互融合，使真正的信息高速公路成为现实，阐述利用H．323标准全面解决视频网络方案。     

Throughput analysis for multicast switches with multiple input queues

This letter analyzes the saturated throughput for multicast switches with multiple input queues per input port. Under the assumptions of a Poisson uniform traffic model and random packet scheduling policy, we derive the multicast switch saturated throughput under different fanouts. To verify the analysis, extensive simulations are conducted with different switch sizes and fanouts. It is shown that the theoretical analysis and the simulation results have a discrepancy less than 1.9%. Results from this letter can be used as a guidance to design the optimal queuing for multicast switches.     

高温氨化合成GaN微晶

分别利用Ga2O3粉末和Ga2O3凝胶作为Ga源,采用NH3为N源,在950℃下,分别将两种反应物与流动的NH3反应20 min合成了GaN微晶。用X射线衍射(XRD)、扫描电子显微镜(SEM)、选择区电子衍射(SAED)对微晶进行结构、形貌的分析,特别是对两种不同途径合成GaN微晶的XRD进行了分析比较。结果表明,当Ga源温度为950℃时两种不同的合成途径均可得到六方纤锌矿结构的GaN单晶颗粒,在氮化温度为850℃和900℃时,利用Ga2O3粉末作为Ga源,仅有少量的Ga2O3转变为GaN;而采用Ga2O3凝胶作为Ga源,在相同的温度下,大部分凝胶经过高温氨化反应均可转化为GaN。     

用于有源电力滤波器的IGBT驱动及保护研究

介绍有源电力滤波器设计中EXB841型绝缘栅场效应晶体管(IGBT)驱动器的驱动原理和电路特点,对IGBT的栅极驱动特性、栅极串联电阻进行了探讨,给出过流保护和过压吸收的有效办法。样机试运行证明此种设计方案可靠、有效。