Solidification microstructure of M2 high speed steel by different casting technologies

The present work investigated the solidification microstructure of AISI M2 high speed steel manufactured by different casting technologies,namely iron mould casting and continuous casting.The results revealed that the as-cast structure of the steel was composed of the iron matrix and the M2C eutectic carbide networks,which were greatly refined in the ingot made by continuous casting process,compared with that by the iron mould casting process.M2C eutectic carbides presented variation in their morphologies and growth characteristics in the ingots by both casting methods.In the ingot by iron mould casting,they have a plate-like morphology and grow anisotropically.However,in the ingot made by continuous casting,the carbides evolved into the fiber-like shape that exhibited little characteristics of anisotropic growth.It was noticed that the fiber-like M2C was much easier to decompose and spheroidize after heated,as a result,the carbides refined remarkably,compared with the case of plate-like carbides in the iron mould casting ingot.     

Functional polymers. LVI. Photochemical behavior of 2(2-hydroxyphenyl)2H-benzotriazole derivatives

Summary Introduction of a second benzotriazole unit into 2(2-hydroxyphenyl)2H-benzotriazole structures causes a significant hyperchromic effect on the absorption spectra, the addition of a second hydrogen bonding hydroxyl group causes a small bathochromic shift, but a significant effect on the fluorescence spectrum.Functional Polymers. LV., Y.C. Jiang, S.K. Wu, A. Sustic, F. Xi, and O. Vogl, Polymer Bulletin 20, 161 (1988)     

石灰石流化床反应器处理矿山酸性废水

根据石灰石流化床反应器处理遂昌金矿含量金属离子的矿山酸性废水的试验数据,计算出该反应器的水力参数,并推导了这一床型操作参数的通用计算公式,与传统的石灰乳中和法相比,该工艺能较大幅度地降低酸性废水的处理成本。