Heat transfer enhancement by Marangoni convection in the NH3–H2O absorption process

The objectives of this paper are to quantify the effect of Marangini convection on the absorption performance for the ammonia–water absorption process, and to visualize Marangoni convection that is induced by adding a heat transfer additive, n-octanol. A real-time single-wavelength holographic interferometer is used for the visualization using a He–Ne gas laser. The interface temperature is always the highest due to the absorption heat release near the interface. It was found that the thermal boundary layer (TBL) increased faster than the diffusion boundary layer (DBL), and the DBL thickness increased by adding the heat transfer additive. At 5 s after absorption started, the DBL thickness for 5 mass% NH₃ without and with the heat transfer additive was 3.0 and 4.5 mm, respectively. Marangoni convection was observed near the interface only in the cases with heat transfer additive. The Marangoni convection was very strong just after the absorption started and it weakened as time elapsed. It was concluded that the absorption performance could be improved by increasing the absorption driving potential (x_vb−x_vi) and by increasing the heat transfer additive concentration. The absorption heat transfer was enhanced as high as 3.0–4.6 times by adding the heat transfer additive that generated Marangoni convection.     

基于CORBA和WEB的产品数据管理体系结构研究

 产品数据管理(product data management,PDM)作为产品信息管理集成框架,已成为当前研究开发型企业提高其核心竞争力的一种重要竞争策略.介绍了PDM技术的起源与发展,阐述了PDM的应用功能框架.结合当今软件技术的发展,分析了基于CORBA和WEB技术的PDM/CPC代表性产品Windchill平台的体系结构,指出了传统PDM过渡到CPC的必然发展趋势.     

医院空调设计的几点体会

空调系统应用于普通房间可能引起空调病 ,应用于医院时此问题将更为突出 ,本文对此类建筑在空调系统设计中应重视的有关问题进行了初步探讨     

通用雷达故障诊断专家系统的设计

目的：为了提高雷达装备故障诊断的效率和可靠性。方法：通过对雷达装备综合测试和故障诊断要求和方法的分析。介绍一种适用于雷达装备的故障智能诊断专家模型，探讨了该模型的基本结构和相应的推理机制及故障诊断策略。结果：结论雷达故障诊断的特点，研究了该模型及诊断方法在雷达装备中的具体应用，证实了该方法是有效的。结论：将自动测试技术和专家系统相结合，可以提高故障诊断的效率和可靠性。     

跳频对GSM网络容量的贡献

本首先提出了射频跳频技术是提高网络容量的关键技术。在此基础上，以跳频为着眼点，分析并量化计算了跳频对干扰的改善度，同时根据跳频对容量的影响，给出现有技术条件下GSM网容量的极限。     

Optimal size,hydraulic retention time and volatile solids loading rate of biogas unit using water hyacinth

With a view to evaluate the effects of hydraulic retention time and volatile solids loading rate on methane production using water hyacinth, experiments were conducted in a 160 dm³ capacity, well-mixed continuous digestion unit at ambient temperature. The optimal design of biogas plant using water hyacinth was elucidated, to provide a unit giving a maximum methane yield of 0.16 nm³ kg^?1 volatile solids added, which was 60% greater than the conventional plant using cowdung. The calculations of optimal design factors were based on reactor size, hydraulic retention time and volatile solids loading rate; considerations were made of capital cost, running costs and operational revenue.     

利用相对坐标轻松完成网格袋布局

网格袋布局管理器是java布局中最有用、最灵活、最复杂、最难掌握的一种布局管理器,实际上,如果我们明白了在布局时它利用了单元格相对坐标定位这一点,以及各个约束条件在布局中的作用,网格袋布局也会变得很轻松。     

烧结机蒸汽系统新老余热管网并网改造

针对烧结机新老蒸汽系统各自独立，使用效率低，不能充分发挥效能的状态，提出了蒸汽系统新老余热管网并网改造，经过一年多的运行，取得了显著的效果。     

铜冶炼企业金银回收率计算方法的选择

针对某厂金、银总平衡情况，分别采用平衡法和连乘法计算金、银回收率，得出两种不同的结果，文章分析了产生不同结果的原因，探讨不同的企业如何根据自身特点，选择与之相适应的金、银回收率计算方法，以便准确地反映本企业的回收率实际水平。     

防汛应用系统整合与完善的探讨

随着黄委“数字黄河”工程建设的开展以及计算机广域网络的扩大、开发技术运行方式的变化和用户的迅速增长，需要将防汛系统资源进行综合利用，满足业务生产需求。“数字黄河”工程规划完成后．我们根据规划首先选择防汛应用系统为突破口，以防汛会商综合信息支持为目标，将单个的防汛应用系统进行规范、完善，最终建成防汛信息综合平台．在平台的基础上实现现有应用系统和新开发系统的集成。