珠海台网络硬盘多频道数字播控系统

叙述了以视频服务器为中心构建的网络化多频道自动播出系统的实践、见解和系统的特点。该系统着重考虑了视频服务器选型、系统可靠性、网络化控制及监控、信号共享等问题；同时，实现了多路同时上载、多路边播边上载，以及自动延时播出等功能。     

20位单片音频数模转换器PCM63P

PCM63P是美国BB公司生产的具有超低失真性能(满量程输出最大为-93dB)的精密20位数模转换器，可应用于低失真频率合成、高级消费品和特殊的数字音频应用等方面。文中介绍了PCM63P的工作原理及应用电路。     

基于AT89C2051的单户可视对讲门铃室内分机的设计

本文介绍一种基于单片机AT89C2501的单户可视对讲门铃室内分机的工作原理及软、硬件的设计与实现方法。     

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我国是煤资源大国，长期来在采煤的同时，抽放排空大量煤层瓦斯，不仅浪费大量资源，还严重污染大气。利用煤层瓦斯发电是解决煤层瓦斯放空的重要途径 。文章介绍一种全新的有别于传统 发动机的瓦斯内燃机空燃自动混合控制装置，其中包括：煤层瓦斯的理化特性、装置的结构、工作原理及工作过程，阐述了结构参数对发动机性能的影响。经过在中心瓦斯工区内燃发动机组群上安装试运行，结果表明：该装置可以适用于高、中、低不同浓度的煤层瓦斯，性能稳定、可靠，达到了设计性能指标，完全满足燃气,内燃机组的使用要求，并取得了很好的经济效益、生态效益和环保效益。     

芦笋保健搅拌酸奶的研制

芦笋是一种兼食品及较强保健功能的稀有蔬菜。对芦笋加工处理、发酵菌种选育驯化、辅料的选择、发酵工艺条件、搅拌方法等一系列的工艺探索,研制出色泽微翠绿、芦笋味典型并适合中老年消费者需求的保健型搅拌酸奶。     

Phase behavior of ternary blends containing dimethylpolycarbonate,tetramethylpolycarbonate and poly[styrene‐co‐(methyl methacrylate)] copolymers (or polystyrene)

The miscibility and phase behavior of ternary blends containing dimethylpolycarbonate (DMPC), tetramethylpolycarbonate (TMPC) and poly[styrene‐co‐(methyl methacrylate)] copolymer (SMMA) have been explored. Ternary blends containing polystyrene (PS) instead of SMMA were also examined. Blends of DMPC with SMMA copolymers (or PS) did not form miscible blends regardless of methyl methacrylate (MMA) content in copolymers. However, DMPC blends with SMMA (or PS) blends become miscible by adding TMPC. The miscible region of ternary blends is compared with the previously determined miscibility region of binary blends having the same chemical components and compositions. The region where the ternary blends are miscible is much narrower than that of binary blends. Based on lattice fluid theory, the observed phase behavior of ternary blends was analyzed. Even though the term representing the Gibbs free energy change of mixing for certain ternary blends had a negative value, blends were immiscible. It was revealed that a negative value of the Gibbs free energy change of mixing was not a sufficient condition for miscible ternary blends because of the asymmetry in the binary interactions involved in ternary blends. Copyright © 2004 Society of Chemical Industry     

A new adaptation of mapping method to study mixing of multiphase flows in mixers with complex geometries

The main objective of the present work is to modify the traditional mapping method for the simulation of distributive mixing of multiphase flows in geometries involving moving parts such as, internal mixers or twin-screw extruders without a limitation on their geometrical periodicity. The periodicity condition, limits the results of traditional mapping method to tracking mapping mesh between specific discrete time intervals or distances for that geometry is repeated, hence, result is only for fixed orientation of rotors. Imaginary domain method is introduced to track mapping mesh from one state to the next free of geometrical periodicity limitations. In this work the method is introduced and its applicability and accuracy is discussed in details. A two-dimensional (2D) simulation of mixing of two Newtonian fluids with different viscosities in an intermeshing internal mixer is used as a test case study. In this example the key issues of ability to predict mixing state in details for all orientations of rotors is presented. To reduce diffusion errors of mapping method in the boundaries of the rotors, mapping mesh refinement technique that relies upon one single reference mesh is also presented.     

Evaluating the mixing performance of a ribbon blender

This paper investigates the effects of processing and equipment parameters of a ribbon blender (i.e. loading method of lubricant, fill level, blade speed and blade design) on magnesium stearate homogeneity. A core sampling technique is used to obtain at least one hundred samples per sampling event, which are extracted throughout the blender and yield a thorough characterization of the entire bed. The results presented here can be used as a guideline to develop appropriate blending processes and characterization protocols for ribbon blenders.     

边坡支护中多种技术措施的综合应用

通过工程实例,介绍了锚杆喷射混凝土支护技术与高压喷射混凝土搅拌桩支护技术在工程中的综合利用,同时也验证了该技术的可行性及经济性。     

Extension of a combined analytical/numerical initial value problem solver for turbulent mixing with combustion

Here, we describe the development of a reacting flow multi-species/combustion methodology, implemented as an extension to the differential reduced ejector analysis (DREA) computer program [Mathematical and computer modeling, vol. 31, 2000, p. 21; Appl. Math. Model. 25 (2001) 427; Comput. Math. Appl. 43(10–11); NASA Contractor Report, 1998]. Use of the single fluid IVP solver framework that was developed for the original DREA model has been directly coupled into the combustion formulation. With these modifications, the analysis has an elementary single step reaction Fuel+Oxidizer→Product combustion capability. Though approximate in nature, the simplicity and efficiency of the DREA formulation make it suitable for its original niche, namely design and preliminary design environments where more complex and expensive models may be inappropriate.