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991.
High temperature studies of Fe-Mn-Al-C alloys with different manganese concentrations in air and nitrogen 总被引:2,自引:0,他引:2
The formation of AIN was studied using a series of Fe-Mn-Al-C alloys with manganese contents from 20 to 40 wt%. All investigations
were carried out in air and nitrogen at 1000° C. The permeability (D
N
N
N) of nitrogen in Fe-Mn-Al-C alloys was found to be a major factor influencing the formation of AIN precipitates which are
always observed underneath the oxide scales of the specimen. The formation of AIN is related to the lower formation rate of
Al2O3 and high permeability of nitrogen; therefore AIN can only be formed in those alloys with a higher manganese concentration
because the specimens are treated in air and in pure nitrogen at 1000 C. 相似文献
992.
万军玲 《湖南工业职业技术学院学报》2010,10(3):49-50,73
在对资金时间价值的内涵进行分析的基础上,文章提出了资金时间价值应用中需要注意的一些事项。这对更好地运用时间价值的观念去解决实际问题具有参考价值。 相似文献
993.
994.
995.
996.
Systematically investigations of the plasticizing effects of triacetine (TAc) on crystallization, chain mobility, microstructure, and tensile properties of the Poly (lactic acid)/triacetine (PLA/TAc) blends are reported. A new transition hump was observed on the tan δ curve of PLAxTAcy specimens at temperatures ranging from ?80 to ?20°C. Thermal, wide angle X‐ray diffraction (WAXD) and dynamic mechanical analysis properties of PLA and PLAxTAcy series specimens suggest that PLA and PLAxTAcy series specimens can hardly crystallize by cooling the melt in room temperature. However, significant recrystallization of α form PLA crystals was found during the annealing processes of PLAxTAcy series specimens. Some “less perfect” β form PLA crystals were found as the TAc contents of PLAxTAcy specimens reach 30 wt %. Further morphological analysis show that the inherent brittle deformation behavior of the PLA specimen was successfully transformed into relatively ductile fracture behavior after blending sufficient but optimum amounts of TAc in PLA resins. Possible reasons accounting for this interesting recrystallization, thermal, microstructure and tensile properties of PLAxTAcy specimens are proposed. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009 相似文献
997.
998.
Zhen-Ning Lou Ye-Xia Li Fu-Qiang Ren Qing Zhang Li Wan Zhi-Qiang Xing Shu-Liang Zang Ying Xiong 《稀有金属(英文版)》2016,35(6):502-508
Amine functional group was grafted to obtain modified persimmon waste gel(NH_2–CPT) with the focus of development of selective recovery of molybdenum from rhenium. The adsorption behavior of the NH_2–CPT gel for various metal ions at varying hydrochloric acid concentrations was studied. It is found that the NH_2–CPT exhibits high affinity for Mo(VI) and no affinity for Re(VII), Cu(II),Fe(III), Mn(VII), and Zn(II) under the operating conditions. The maximum adsorption capacity for Mo(VI) is 172 mgág-1, and the adsorption behavior obeys the Langmuir model. Owing to Mo(VI) as poly-anions, the adsorption mechanism of molybdenum anions could be explained as the anion exchange reactions at weak acid concentration, while neutral molecules could be explained as the complexation reactions at strong acid concentration,respectively. In addition, its excellent adsorption characteristics for Mo(VI) are confirmed by separation of Mo(VI)from Mo to Re containing industrial effluent. 相似文献
999.
1000.
随着经济的快速发展,我国桥梁建设以低成本、低污染、质量优、耐久使用、生态环保存为发展目标,走向了绿色设计施工方向。本文结合绿色桥梁设计理念,分析了生态环保的桥梁设计需要,希望能为未来桥梁设计的发展奠定基础。 相似文献