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不同人工晶体材料的特性 崔海坡1 (1.上海理工大学医疗器械与食品学院,上海,200093) 摘要:人工晶体材料由最初的聚甲基丙烯酸甲酯发展到今天的丙烯酸酯多聚物等,一直在不断地改良变化.不同人工晶体材料的性能各有其局限性,选择一种合适的人工晶体对白内障复明手术具有十分重要的意义.本文对目前常用的人工晶体材料基本性能及其优缺点进行了综述,并对不同人工晶体材料的临床性能进行了详实的对比分析,从而为人工晶体生产者及临床医师在选择人工晶体材料时提供一定的参考. 关键词:人工晶体; 材料; 性能; 对比; [全文内容正在添加中] ......
具有不同特征值的矩阵多项式 吴世玕1 (1.南方冶金学院理学院,江西,赣州,341000) 摘要:讨论了具有不同特征值的矩阵多项式的一些性质,及其与矩阵对角化的关系. 关键词:特征值; 多项式; 矩阵; 对角化; [全文内容正在添加中] ......
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TiO2-C体系在不同气氛下的反应刘彦祥1,2,侯新梅1,2,周国治1,21. 北京科技大学钢铁冶金新技术国家重点实验室2. 北京科技大学冶金与生态工程学院理化系摘 要:为了解TiO2-C体系在不同气氛下的反应过程,以w(TiO2)≥98.0%的锐钛矿型TiO2和w(C)≥98.8%的活性炭为原料,在热力学计算的基础上,结合室温1 773 K下的TGA,XRD和SEM分析,研究了m(TiO2)∶m(C)=1∶0.3的TiO2-C体系分别在Ar和N2气氛下热处理过程中的物相变化及显微形貌.结果表明:TiO2的......
三个不同产地橄榄石的对比研究李谦颖1,徐钦龄1,刘奕萱1,阮青锋11. 桂林理工大学地球科学学院摘 要:利用宝石显微镜等宝石学测试仪器和电子探针仪,从宝石的内,外部特征和化学成分等方面系统对比分析了中国吉林,缅甸和巴基斯坦三个产地橄榄石的特征.研究表明:三个产地橄榄石的外观特征和常规宝石学参数基本相似,但巴基斯坦橄榄石的双折射率(0.037~0.038)略大于吉林和缅甸橄榄石的双折射率(0.036),巴基斯坦橄榄石的相对密度(3.373~3.377)也大于吉林和缅甸橄榄石的相对密度(3.291~3.336)......
the threshold value, the interaction susceptibility to temperature decreases evidently.Key words:water-rock interaction; temperature coupling; surface topography; fractal parameters; statistical parameters......
performance of 6005A Al alloy was investigated by hardness test, intergranular corrosion test, optical microscopy and TEM observation. The results show that the intergranular corrosion susceptibility... of the artificial ageing after water quenched. However, IGC susceptibility increases with the increase of aging time, and reaches the peak value after artificial ageing for 12 h, while the hardness......
in the 10% NaCl solution has the best protective effect on the matrix.The SCC susceptibility does not increase with increasing the chloride ion concentration,the lowest SCC susceptibility occurs when the NaCl concentration is 10%,and the specimens show higher SCC susceptibility in the 5% NaCl and 20% NaCl solutions.关键词:......
the susceptibility of specimens given a two-step heat treatment. The results reveal that IGC occurs in the specimens aged at the temperature range of 600–750℃ for a short time. The aging time that is required to cause IGC decreases with the increase of aging temperature. A longer aging treatment can reduce the susceptibility to IGC. The microstructural observation shows that M23C6 precipitates form along......
果与实际情况基本吻合.分析结果表明,涡轮叶稍处产生热裂的根本原因是凝固过程中产生了拉应力,应力值越大,铸件处于热裂敏感区的时间越长,热裂倾向性越大;采用较高的模壳温度和较低的浇注温度有利于降低铸件的热裂倾向.关键词:K418合金;车用增压涡轮;热裂;浇注工艺;数值模拟Hot tearing susceptibility analysis and prediction of K418... in order to solve the hot tearing problem in the K418 superalloy auto turbocharger turbine wheel. The susceptibility of hot tearing defects was predicted by analyzing the simulation results......