Behavior of ZrO2-C Refractories in Thin-strip Casting of Steel

Zirconia graphite refractory is used as a core-nozzle in the thin-strip casting of steel. Post-mortem analysis of used refractory was performed in an effort to establish the failure mechanism. Corrosion behavior was studied against molten steel with Mn O- SiO 2based liquid inclusions. Corrosion of these materials involves dissolution and oxidation of graphite in the matrix followed by penetration of liquid slag leading to degradation of ZrO 2particles. Thermodynamic equilibrium calculations were performed to study this corrosion mechanism.     

WAVE INTERACTION WITH PERFORATED CAISSON BREAKWATERS

The reflection coefficient of perforated caissons and the total horizontal forces acting on them were experimentally and numerically analyzed and discussed when wave propagates normally. To consider the viscosity effect of fluid and nonlinear action of waves on structures, the VOF (Volume Of Fluid) method combined with the k-ε turbulence model was used to simulate the interaction between waves and structures. Governing equations were solved with the finite difference method. Through 2D experimental study in the wave flume, the empirical relationship between the reflection coefficient of perforated caissons and the main affecting factors were obtained from the experimental data using the least square method. Also the correlation between the ratio of the total horizontal force acting on perforated caisson and the force acting on solid caisson and the main affecting factors were regressed from the experimental data.     

IEEE802．16和WiMAX

在无线局域网(WLAN)势头正劲之际，最近又出现了无线城域网(MAN)技术。与为无线局域网制定802．11标准一样，IEEE为无线城域网推出了802．16标准，同时业界也成立了类似WiFi联盟的WiMAX论坛。无线城域网技术为何会紧跟WLAN之     

意气风发的日本三大3G运营商

许可证的拍卖炒作和世界电信业的下滑严重影响了原本领跑的欧洲3G的健康发展,曾经一度使3G变成了“3D“--债务、推迟、怀疑(Debt、Delay、Doubt).在欧洲受到挫折时,日本变成率先吃螃蟹的国家.NTT DoCoMo于2001年10月成为采用WCDMA正式开通3G业务的第一家运营商.此后,J-Phone和KDDI也相继投入这一行列.经过一年的摸索,日本对3G似乎更加坚定信心,三大3G运营商纷纷亮出自己的发展策略,意气风发,锐意奋进.……     

柴油润滑性能试验方法研究

随着我国大型运输机、挖掘机等重型柴油车的出现，还有对空气质量指标的限制，对汽车尾气排放指标更加苛刻，要求柴油中的硫含量越少越好，但随着柴油中的硫含量的减少，柴油的润滑性能变差，为了解决这一问题，需在柴油中加入润滑性添加剂，来提高柴油的润滑性能。为了配合兰州润滑油研究开发中心柴油及柴油润滑性添加剂的研究与开发，在磨损四球机上用L9(3^4)正交方案考察并确定了试验条件。该试验方法的特点是试验周期短，费用低，对不同质量级别的柴油及柴油润滑性添加剂具有较好的区分性和重复性，对研发中心进行柴油及柴油润滑性添加剂的研究起到了一定的作用。     

Charge： Glowing in the Dark

Many areas of structure analysis have focused on finding the locations of the atoms. If, instead of the atoms, we knew the positions of the electrons we would in fact know much more, and in most respects knowing where the nuclei are is not important. There is a long history of measurements using precise electron diffraction or X-ray diffraction of the average charge density in materials, but extending beyond to local charge density is, as yet, an unexplored area.     

值得关注的十大无线通信技术

以下十大无线通信技术今年在美国引起了关注,它们是WiMAX、WiFi网状网拓扑、客户轮廓管理、安全性、移动/WiFi漫游、企业的WiFi交换与管理、按键通话、移动终端操作系统与界面的开发、UMTS/WCDMA和软件定义的无线电.