对数D/A转换器及在水声系统中的应用

简要介绍了对数D／A转换器AD7111的结构、特点、工作原理，并与同类产品AD7110进行了对比。指出了使用中的注意事项。给出了应用于声纳和水下寻的声系统试验测试的半物理仿真系统设计实例，该系统设计获部级科技进步二等奖。     

汽车共用零部件钢材理论订货量预报技术的开发

近年来,随着汽车制造产业发展迅速,对汽车零部件所用钢材的需求量急剧增加。各钢铁生产企业为加大在此领域的市场份额,不仅从产品质量和技术水平等方面进行提高,同时更加注重对客户的服务质量。为此,针对当前普遍使用的理论订货量模型所存在的缺陷,在供应商管理库存思想的基础上,利用动态库存管理的相关数据,同时兼顾季节对库存的影响以及实际生产中的最新成品率变化,开发了一套新的汽车共用零部件钢材的理论订货量预报技术,并将其应用到生产实践,取得了良好的使用效果,有效地提高了企业对汽车板客户的服务质量,为企业带来较大经济效益,具有进一步推广应用的价值。     

下一代制冷剂--历史回顾、思考与展望

回顾了制冷剂从早期使用至现在的进步历程,探讨了未来方向与一些候选制冷剂.根据所定义的选择标准把此历程划分为四代制冷剂.逐一用这些标准讨论了较早工质的替代,并说明了某些早期制冷剂例如那些现在所称的天然制冷剂重新受到关注的过程.考察了对现有国际协定相关方案的展望,其中包括了分别为防止平流层臭氧耗损与全球气候变化的蒙特利尔与京都议定书的分析.还考察了其他环境问题和更长远的国际与地区性的控制措施.这种讨论说明,如果仅仅孤立地看待各个环境问题,而不是把若干环境问题作为整体而采取综合协调的对策,可能会对环境造成无意识的破坏,这种环境破坏几乎肯定将来还需要再采取挽回措施.可以确定,一些即将出台的政策与管制条例的变化可能对下一代制冷剂的选择会有重要影响.     

Interactions between fine combustion droplets

Interactions between fine combustion droplets were directly observed using microscopic flow visualization and high speed photography. The observations revealed “attracting-revolving-repulsing” interactions between the droplets. Force analyses showed that the traditionally considered interparticle forces, including drag, gravitation, the Coulomb force and the van der Waals force, cannot explain these interactions. However, the induced dipoles on the droplets due to the non-uniform distribution of surface charges on the fine droplets have important influence on such interactions. Therefore, the inter-dipole forces must be taken into account in the interaction force analysis as well as the Coulomb force between the net charges. The inter-dipole force includes components in the radial and azimuthal directions and is inversely proportional to r⁴. This force causes the particles to revolve and repel each other at small distance. The combined effects of the inter-dipole force and the traditionally considered forces give a complete explanation for the particle interactions.     

简易液柱式湿法烟气脱硫装置的试验研究

介绍了一种简易液柱式湿法烟气脱硫装置,对该装置的脱硫特性进行了试验,研究分析了一些重要因素对系统脱硫效率的影响变化规律。结构表明;当塔内烟气速度小于3m/s。液气比为12L/m^3时,系统的脱硫效率在80%以上,整个试验装置的阻力损失小,运行可靠,有利于装置在工业上的实际应用。     

Catalytic reduction of nitric oxide by methane over CaO catalyst

The selective catalytic reduction of nitric oxide by methane was studied over CaO catalyst in a bubbling fluidized bed in the temperature range of 800–900 °C, in which NO cannot be reduced by CH₄ without CaO catalyst. The nitric oxide conversion was found to depend on oxygen and CH₄ feed concentration, and also on temperature. In addition, the presence of water vapors in the flue gas enhanced the NO reduction admirably well in the absence of O₂. But water vapor has an inhibiting effect on the reaction while O₂ is present in the flue gas. The addition of CO₂ poisoned the CaO catalyst and exhibited a detrimental effect on NO conversion at the working temperature range, 800–900 °C. However, with a temperature rise to 900 °C the CO₂ poisoning effect on NO reduction was weakened. The mechanism was studied and discussed according to the references in the paper. This work was presented at the 6 ^th Korea-China Workshop on Clean Energy Technology held at Busan, Korea, July 4–7, 2006.     

石灰石／石灰—石膏湿法脱硫反应塔模型比较

就二氧化硫的污染控制最常用方法－石灰石／石灰－石膏湿法脱硫的几种主要的反应塔模型进行了比较。讨论了已经发展的几种基本传质吸收模型,包括薄膜理论、渗透理论以及表面更新理论在脱硫反应塔建模中的应用,特别是对于新型脱硫塔－液柱脱硫塔的建模作了初步探索,并从模型基本理论的角度分析了现行的各种脱硫反应塔工艺之间的差别,以及如何通过加强传质反应来提高脱硫设备的运行效率等问题。     

Mercury speciation and its emissions from a 220 MW pulverized coal-fired boiler power plant in flue gas

Distributions of mercury speciation of Hg⁰, Hg²⁺ and Hg ^P in flue gas and fly ash were sampled by using the Ontario Hydro Method in a 220 MW pulverized coal-fired boiler power plant in China. The mercury speciation was varied greatly when flue gas going through the electrostatic precipitator (ESP). The mercury adsorbed on fly ashes was found strongly dependent on unburnt carbon content in fly ash and slightly on the particle sizes, which implies that the physical and chemical features of some elemental substances enriched to fly ash surface also have a non-ignored effect on the mercury adsorption. The concentration of chlorine in coal, oxyge nand NO _x in flue gas has a positive correlation with the formation of the oxidized mercury, but the sulfur in coal has a positive influence on the formation of elemental mercury. This work was presented at the 6 ^th Korea-China Workshop on Clean Energy Technology held at Busan, Korea, July 4–7, 2006.     

聚合级CGF队形变换的仿真

文章以美军坦克排为例,提出了用逼近法建立队形变换这一战术动作的数学模型,并探讨了用计算机仿真实现的方法,该技术已在装甲兵数字化部队作战仿真实验室中得到应用。     

山丘小区域地下水补给量的计算

鲁中山丘区是由各种不同地层出露组成的,在多个水文流域水循环要素分析计算的基础上,对河川径流进行基流分割,反推地下水补给量,建立流域年均降水入渗补给系数与各种地层出露面积占流域总面积权重间的最佳回归方程,利用该方程和地层分布及降水量推算山丘小区域地下水的补给量,为山丘小区域地下水持续开发利用与保护提供科学依据。