Energiedissipation und Energieflüsse während des Tablettiervorganges

The tableting process causes a temperature increase due to dissipation of energy. Therefore, with time the temperature of the tablets and the tablet press increases. Depending on the calculated tablet temperature, this temperature increase is discussed for different compression forces and lubricant concentrations. Two different measurement techniques are presented and compared.     

UUV自航发射鱼雷过程仿真

无人水下航行器(UUV)外挂鱼雷具有重要的战术价值.由于UUV体积小、质量轻,自航发射鱼雷时运动状态会发生改变.为了定量分析这种变化以验证发射的可靠性,建立了UUV自航发射鱼雷的运动模型,根据此模型利用FLUENT对发射过程进行了仿真.仿真结果表明,UUV发射鱼雷时运动状态会发生一定的变化,但采用自航发射仍然具有可行性.同时得出鱼雷脱离发射导轨时的运动参数,为精确计算鱼雷的外弹道提供了依据.     

壁挂锅炉检测自动配气装置设计

为保证壁挂锅炉的质量，检测其安全装置和热工性能是否达到要求，需要根据不同地区的气源进行配气。根据道尔顿分压定律，利用中压储制度进行混气，设计了一套低压储气、连续的自运配气装置。并可设定三种基因配气气源的中压充气压力，控制配制的试验气的华白数、燃烧势满足国标要求。该装置操作简单，运行可靠。     

Bürohochhaus im Palais Quartier — ein besonderes Bauprojekt in der Innenstadt von Frankfurt/Main

Dieser Beitrag geht auf die Planung und die Bauausführung des Bürohochhauses des “Palais Quartier” in der Innenstadt von Frankfurt am Main ein. Beschrieben werden die Konstruktion und der Bauablauf des 5‐geschossigen Kellerkastens und der Abfangung eines 12 m × 15 m großen Gebäudeteils sowie die Planung, im Speziellen die Verformungsuntersuchung für die Stahlbetonstützen. Office Tower in the Palais Quartier — a special construction project in the city of Frankfurt/Main. This article covers the design and the construction of the office tower of the ”Palais Quartier“ in the city center of Frankfurt am Main. In the following, the structural design and the construction work of the 5 basement levels and the overhanging part of the building with dimensions 12 m × 15 m and 28 levels will be described. Finally, an analysis of the deformation of the columns will be presented.     

Mikrostrukturelle Veränderungen von Magnesium‐Druckgusslegierungen nach langzeitiger thermischer Beanspruchung

Microstructural Changes of Pressure Die Cast Magnesium Alloys after Long‐Term Thermic Loading The expansion of the application of pressure die cast magnesium alloys for automobiles requires the development of new alloys and the comprehensive assessment of available alloys on aggravated conditions, too. Such conditions are also given at higher temperatures, which can cause the creep of the material and lead to the component failure. Because the microstructural stability decisively depends on the thermic loading, this paper deals with the change of the microstructure and the hardness of the alloys AZ91, AM50 and AE42 after a long‐term annealing at 150 °C and 200 °C in comparison to the pressure die as‐cast condition. The results reveal clear differences of the microstructural stability of the alloys AZ91 and AM50 on the one hand and the alloy AE42 on the other hand. Due to the long‐term annealing at 150 °C the alloys AZ91 and AM50 show chiefly an intense precipitation of Mg₁₇Al₁₂ from the Al‐rich eutectic α‐phase. Furthermore at 200 °C, it is observed the coagulation and coarsening of these precipitates, too. The last appearances are connected with a weakening of the material. Regarding the alloy AE42, the changes of the precipitation state are not so intensely and do yet not lead to a microstructural weakening.     

三门口跨海大桥南门桥深水基础施工技术

介绍了三门口跨海大桥南门桥深水基础的工程概况，针对工程特点，详细阐述了水下钻孔灌注桩、承台施工的要点和保证工程质量的措施，可供类似工程借鉴。     

Solid solubility extension of copper‐tin immiscible system during mechanical alloying

In this paper, copper‐5 wt.%‐tin (Cu‐5wt%Sn) powder mixture was mechanically alloyed in order to study the solid solubility extension during the alloying process. Nanocrystalline supersaturated solid solution has been prepared in this system by high energy ball milling. Based on the thermodynamic model, the Gibbs free energy change in this alloy system during the formation of solid solution is calculated to be positive, which means that there is no driving force to form solid solution in copper‐tin (Cu?Sn) immiscible system. It has been found that a large fraction of grain boundaries and a high density of dislocations play a significant role in the solid solubility extension of immiscible copper and tin.     

混凝土预制底板钢吊箱水中桥墩承台施工技术

通过上海崇明越江通道长江大桥B1标工程水中墩施工事例,详细叙述了采用混凝土预制底板钢吊箱施工桥梁水中墩承台的设计计算和施工方法。