Chemical Nickel Plating

Metal layers can be deposited from aqueous solutions not only by electric current as in electroplating but also by strong reducing agents. Chemical deposition of nickel on metallic and nonmetallic substrates, together with the long-known silvering of glass, are the most widespread examples. This remarkable reaction has recently found a variety of industrial applications mainly in the preparation of corrosion-resistant, hard, and wear-resistant protective layers, in the metallizing of plastics, and in electronics.     

校园网设计与建设初探

从确立建设校园网的目标、校园网的技术方案设计、信息资源建设、网络管理等4个方面，探讨了校园网的设计与建设问题。     

Separation with Supercritical Gases: Practical Applications

Extraction with supercritical gases combines, to a certain extent, the characteristics of both distillation and extraction; the term “destraction” is therefore proposed for this method of separation. The principles of the method are illustrated in this article by a series of color photographs comparing extraction and destraction. Of the practical uses of this new method may be mentioned the separation of cod-liver oil into 50 fractions, each differing in saponification value and iodine number, by means of supercritical ethane and, in particular, the decaffeination of raw coffee with supercritical carbon dioxide.     

Large-Scale Industrial Plant for Extraction with Supercritical Gases

Criteria for the design and construction of plant for obtaining carrier material or extracts are discussed for the example of the extraction of natural products with supercritical carbon dioxide. The parameters to be established and the course of the process in a large-scale plant are indicated. Plant engineering and optimization must be attuned to specific process-technological and construction problems.     

Chromatography in fluidized beds

Summary Chromatography is carried out under the conditions of fluidization, in long, straight tubes under organized and non-organized conditions. Under non-organized conditions the column is filled only with a sorbent. In organized conditions, either metal coils are added into the column or a segmented column is utilized with metal grids. The results obtained are compared to those obtained under fixed-bed conditions when the column is completely filled with the sorbent. Organized fluidized beds provide a significant decrease in longitudinal bandspreading.     

一种可在线更新的PET实时查找表电路的设计与实现

介绍了一种正电子发射断层成像术实时查找表电路。该电路接收符合电路输出的位置信号和能量信号,用查表的方法完成重心法中的除法运算,然后再第二次查表得到该γ光子所入射到的晶格的离散化坐标值和能量阈值,并完成能量甄别以剔除部分散射事件。此外,该电路还结合了呼吸门控和心电门控功能。查找表存储在flash器件中,由CPLD控制读写。本设计的特点是利用硬件电路来完成查找表功能,效率更高,每次事件的查表寻址的延迟时间小于100ns,并且可以在线更新查找表的内容,使用方便。另外,还说明了用CPLD来读写NORflash的方法,以及该电路与系统中其它模块间的数据通信方法。     

基于生态学理论的工业生态系统比较研究

本文从工业系统的生态性入手,与传统的生物生态系统做以比较分析。以物质循环和能量流动为重点,主要从相似性、相异性两个个方面比较分析了工业生态体系。对生态工业园建设及循环经济的开展有一定的参考价值和指导意义。     

工业锅炉水质分析中炉水协调磷酸盐的PLC智能控制

针对当前工业锅炉炉水协调过程中,加磷酸盐主要以人工为主,成本高、劳动强度大、存在很多人为因素,导致控制不连续的问题,提出一种新的炉水协调磷酸盐PLC智能控制方法,给出PLC智能控制系统的总体结构,主要包括被控对象、变频器、可编程序控制器(PLC)、pH表、磷酸根表等。两台变频器用于控制两台加药泵,PLC 智能控制器用于实现R值计算、加药品种选择和加药泵转速控制。介绍了R值计算的详细过程,通过加药品种选择算法和加药泵转速控制算法,实现PLC控制器对炉水协调磷酸盐的控制功能。实验结果表明,所提方法不仅能够将水质控制在合理范围内,而且控制精度高,所需时间少。     

Cost-Effective Migration from Sub-Lambda to Wavelength-Based Metro Networks

This article will discuss the importance of hybrid coexistence of sub-lambda grooming with wavelength-based services for driving down costs and maximizing the use of metro bandwidth, as well as enabling next-generation lambda-based services. The article will also address migration to all optical metro networks.     

The Design of Passive Optical Networking+Ethernet over Coaxial Cable Access Networking and Video-on-Demand Services Carrying

Abstract

Video on demand is a very attractive service used for entertainment, education, and other purposes. The design of passive optical networking+Ethernet over coaxial cable accessing and a home gateway system is proposed. The network integrates the passive optical networking and Ethernet over coaxial cable to provide high dedicated bandwidth for the metropolitan video-on-demand services. Using digital video broadcasting, IP television protocol, unicasting, and broadcasting mechanisms maximizes the system throughput. The home gateway finishes radio frequency signal receiving and provides three kinds of interfaces for high-definition video, voice, and data, which achieves triple-play and wire/wireless access synchronously.