唐钢薄板坯连铸连轧生产中半无头轧制技术分析

介绍了热轧薄带钢生产中半无头轧制的优点，并对唐钢薄板坯连铸连轧生产中半无头轧制的工艺方案和关键技术进行了技术分析。     

PbS-Sb2S3-FeS三元系在水蒸气气氛下的铅锑分离

在1073K下通过测定三硫化锑和硫化铅的挥发速度,研究了PbS-Sb_2S_3-FeS三元系在水蒸气气氛下的铅锑分离规律。X-射线衍射结果表明,焙砂由PbS、Fe_3O_4、FePb_4Sb_6S_(14)、Pb_5Sb_4S_(11)和FeSb_2O_4组成。当试样中FeS含量在5％～7％时,铅锑分离效果最好。当试样中FeS的含量≥10％时,铅锑分离效果较差,这时过量的FeS会与Sb_2S_3和PbS形成复杂的硫化物(FePb_4Sb_6S_(14)、Pb_5Sb_4S_(11))或被氧化成F4Sb_2O_4,使锑的挥发变得困难,导致残留在焙砂中的锑含量升高。     

真空蒸馏脱硒的研究

本文从理论上分析了真空蒸馏脱Se的影响因素时间和温度,并通过实验给予验证,提出了最佳条件,对工业采用真空蒸馏脱出含Se物料中的Se具有一定的指导性。     

铸造湿型小件缺陷产生的原因与控制

通过对铸造湿型小件产品缺陷典型实例的原因分析，从型砂的选择及配制、造型工艺、浇注工艺等方面提出控制缺陷产生的工艺方法。     

全封闭Ar气保护电渣重熔GH4169合金

上海五钢采用ALD 5t全封闭Ar气保护电渣重熔炉 ESR(Ar)冶炼了GH4 16 9合金锭 ,分析结果表明 ,ESR(Ar)电渣锭氧、硫含量和锭头尾碳、铝、钛之差远低于一般ESR工艺 ;VIM(真空感应熔炼 ) +ESR(Ar)工艺冶炼合金中平均氧含量 6× 10 - 6 远低于VIM +VAR(真空电弧重熔 )工艺冶炼合金中平均氧含量 13× 10 - 6 ,所以ESR(Ar)工艺脱氧效果优于VAR工艺     

无键联接传动的特点及锥面弹性衬套设计和应用

无键联接在特殊行业和工况中是键联接传递动力和运动的有力补充,介绍了工程上应用的圆弧三边形型面联接、弹性环无键联接、圆柱面过盈联接等几种无键联接传动方式及其工作原理,并分析了各自的性能特点和应用情况。针对无键联接传动的特点、特殊行业和工况的应用实际,设计了锥面弹性衬套无键联接传动结构并介绍了其在工程中的实际应用。     

Mechanism of heat transport in nanofluids

We have calculated thermal conductivity of alumina nanofluids (with water and ethylene glycol as base fluids) using temperature as well as concentration-dependent viscosity, η. The temperature profile of η is obtained using Gaussian fit to the available experimental data. In the model, the interfacial resistance effects are incorporated through a phenomenological parameter α. The micro-convection of the alumina nanoparticle (diameter less than 100 nm) is included through Reynolds and Prandtl numbers. The model is further improved by explicitly incorporating the thermal conductivity of the nanolayer surrounding the nanoparticles. Using this improved model, thermal conductivity of copper nanofluid is calculated. These calculations capture the particle concentration-dependent thermal conductivity and predict the dependence of the thermal conductivity on the size of the nanoparticle. These studies are significant to understand the underlying processes of heat transport in nanofluids and are crucial to design superior coolants of next generation.     

Study of chemical modifications and fungi degradation of thermally modified wood using DRIFT spectroscopy

A mild thermal treatment of wood leads to improved macroscopic properties (dimensional stabilization and resistance against fungal degradation). The chemical modifications induced by the thermal treatment were investigated by means of DRIFT spectroscopy on wood blocks in order to explain the new macroscopic properties on a molecular level. The formation of new ether linkage was observed in addition to the well-known acidic hydrolysis reactions of wood. Fungal attack was found to take place even after thermal degradation of pentosanes by a standard oxidative way. A competition between depolymerization and condensation reactions was observed.