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Effects of SnO<sub>2</sub>Addition on the Properties of Alumina-Magnesia Refractory Castables

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New Journal of Glass and Ceramics 2015年第1期5卷 1-7页

作者： Wenjie Yuan qingyou zhu Chengji Deng Hongxi zhu The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and Technology Wuhan China

Alumina-magnesia refractory castables have been widely used in the wall and bottom impact pad of steel ladles. The properties of alumina-magnesia refractory castables with SnO2 additive in 0 - 5 wt% range were investigated. The phase composition, microstructure, physical and mechanical properties of these refractories were studied. The results showed that the addition of SnO2 could have a great influence on the properties of alumina-magnesia refractory castables. The expansion, apparent porosity and strength of refractories with SnO2 were all more prominent than those of reference samples, which were attributed to the formation of CA6 and enhanced bonding. Meanwhile SnO2 could react with spinel and CA6 to form solid solution.

关键词： Castables SnO2 Spinel Calcium Hexaaluminate

Fractal Analysis of Fracture Surfaces in Refractories

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China's Refractories 2014年第1期23卷 27-31页

作者： YUAN Wenjie zhu qingyou DENG Chengji zhu Hongxi The State Key Laboratory Breeding Base of Refractories and Ceramics Wuhan University of Science and Technology

Fractal analysis of fracture surfaces in different kinds of refractories including magnesia-carbon and magnesia-chrome refractories was *** fractal dimensions of fracture surfaces for three points bending test were determined by slit island *** results show that the cold modulus of rupture increases with fractal dimension increasing due to the change in fracture mode depending on the bonding mechanism for a certain refractory material.

关键词： refractories fractal fracture surface cold modulus of rupture

A Test Method for Torsion Strength of Refractory Materials at Elevated Temperatures

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China's Refractories 2018年第3期27卷 28-31页

作者： zhu qingyou GE Shan YIN Yucheng LIU Zhiqiang The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and Technology

New apparatus for the determination of torsion strength of refractory materials at elevated temperatures has been developed in this work. With the employment of heating wire and induction heating unit,this device can carry out torsion strength test at high temperatures at the heating rate ranging from 10 ℃/min to 200 ℃/*** strength of high alumina brick,magnesia brick and Si3 N4 bonded SiC brick has been tested at different heating rates of 10 ℃/min,100 ℃/min and 200℃/min,separately. Results indicate that,for high alumina brick,the tested torsion strength at the heating rate of 10 ℃/min is very close to that at 100 ℃/min,but very different from that at 200 ℃/min. The tested torsion strength of magnesia brick at different heating rates differs greatly,while that of Si3 N4 bonded SiC brick is similar. This suggests that the structure of refractory materials with poor thermal shock resistance might be damaged when the heating rate of 200 ℃/min was applied,but the heating rate of 100 ℃/min is possible for a lot of refractory products. At fast heating rates,it takes only1 h to finish a test at elevated temperatures,thus saving a lot of time and energy.

关键词： torsion strength heating rate refractory materials local heating

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井眼轨迹预测理论及方法研究

天然气工业 2004年第4期24卷 38-40页

作者：祝效华刘清友李红岩童华 "油气藏地质及开发工程"国家重点实验室.西南石油学院中原油田钻井二公司

科学的井眼轨迹设计方法和精确的井眼轨迹预测与控制技术是确保定向井、丛式井、水平井、大位移井、老井重钻、复杂结构井等一系列特殊工艺井钻井成功 ,降低钻井成本的关键技术。科学的井眼轨迹预测不仅可以指导轨迹设计、预测实钻井眼... 详细信息

科学的井眼轨迹设计方法和精确的井眼轨迹预测与控制技术是确保定向井、丛式井、水平井、大位移井、老井重钻、复杂结构井等一系列特殊工艺井钻井成功 ,降低钻井成本的关键技术。科学的井眼轨迹预测不仅可以指导轨迹设计、预测实钻井眼轨迹参数 ,而且可以优化下部钻具组合、提高轨迹控制精度。文章对井眼轨迹预测理论及方法作了简要的分类 ,介绍了几种目前常用的井眼轨迹预测方法及其特点 ;提出了基于钻井系统动力学的井眼轨迹预测理论及方法 ,建立了新的预测模式 ,提出了井眼轨迹不仅与下部钻具组合和钻头与岩石互作用有关 ,而且与钻柱的振动和钻井液水力作用有关。

关键词：井眼轨迹系统动力学钻井力学钻头岩石互作用钻井液

压力排气法在一次性精密过滤器输液器排气故障中的应用

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护理实践与研究 2009年第12期6卷 10-11页

作者：朱清有广东省东莞市人民医院骨科 523000

目的:探讨压力排气法在一次性精密过滤器输液器排气故障中的应用效果。方法:将280例排气故障随机分为两组,实验组160例采用压力排气法,对照组120例采用常规排气法。结果:实验组排气成功率明显高于对照组,排气成功所需时间明显少于对照... 详细信息

目的:探讨压力排气法在一次性精密过滤器输液器排气故障中的应用效果。方法:将280例排气故障随机分为两组,实验组160例采用压力排气法,对照组120例采用常规排气法。结果:实验组排气成功率明显高于对照组,排气成功所需时间明显少于对照组。两组相比,均P<0.01。结论:采用压力排气法能迅速处理排气故障,提高1次排气成功率,有效节省排气时间。

关键词：压力排气法精密过滤器输液器排气故障处理

New insight into the origin and evolution of the flora and fauna of Hainan Island, China

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Science China Earth Sciences 2025年第1期68卷 52-61页

作者： Hua zhu Center for Integrative Conservation Xishuangbanna Tropical Botanical Garden Chinese Academy of Sciences Yunnan International Joint Laboratory of Southeast Asia Biodiversity Conservation Yunnan Key Laboratory for the Conservation of Tropical Rainforests and Asian Elephants

The origin of the biota of Hainan Island, China, remains a fundamental scientific problem. Comparative studies on the biota, geological tectonics, and paleomagnetism proposed that during the Eocene, Hainan Island connected Vietnam and Guangxi, and then moved to the southeast to reach its present location. This review mainly discusses its biota origin from molecular phylogeny and palaeobotanical research. The formation and evolution of the biological groups of Hainan Island were identified via research on their genomes, phylogeny, and molecular biogeography. This research showed that the genera and species that appeared and diverged early in their evolution(i.e., before the Miocene) can be explained by the land connection between Hainan Island, Vietnam, and Guangxi during the Eocene-Oligocene. According to Southeast Asian tectonic theory, in the Middle Miocene(at about 15 million years ago), Hainan Island had moved to its present position. The population and genetic divergence of species with late divergence times(after 15 Ma) can be reasonably explained by the close proximity(or land connection) between Hainan Island and the Leizhou Peninsula, enabling genetic communication between Hainan Island and the Chinese mainland, but have exceptional cases. Conclusions have been obtained through palaeobotanical studies, showing that in the Eocene-Oligocene period, southwest China and Hainan Island had subtropical vegetation and flora. However, the fossil group in southeast China(in Maoming, near present-day Hainan Island) in the Late Eocene indicated a tropical rainforest vegetation and flora. This suggests that in the Paleogene, Hainan Island may have been located near or on the southwest border of Guangxi and northern Vietnam, rather than in its present location. The floristic division of the flora of Hainan Island basically presents a northeast-southwest inclined distribution pattern. This pattern can be explained by the counterclockwise rotation of Hainan Island during i

关键词： Molecular phylogeny Biogeography Paleobotany Origin of flora and fauna Hainan Island of China

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反应烧结碳化硅高温性能的研究进展

耐火材料 2022年第1期56卷 75-81页

作者：董博余超邓承继祝洪喜丁军朱青友武汉科技大学省部共建耐火材料与冶金国家重点实验室湖北武汉430081

反应烧结碳化硅具有优良的力学性能、抗侵蚀性能和抗氧化性能等优点,是一种高致密度、低成本和净尺寸成型的材料。但由于反应烧结法的特殊工艺,反应烧结碳化硅中常含有较多游离硅,严重损害了材料的高温性能。主要阐述了反应烧结碳化硅... 详细信息

反应烧结碳化硅具有优良的力学性能、抗侵蚀性能和抗氧化性能等优点,是一种高致密度、低成本和净尺寸成型的材料。但由于反应烧结法的特殊工艺,反应烧结碳化硅中常含有较多游离硅,严重损害了材料的高温性能。主要阐述了反应烧结碳化硅高温力学性能、抗氧化性能、导热性能和抗热震性能的研究现状,并总结了近年来降低游离硅含量、提高反应烧结碳化硅力学性能的主要措施,包括优化材料制备工艺、引入补强增韧相。并展望了反应烧结碳化硅未来的研究方向。

关键词：反应烧结碳化硅游离硅高温性能制备工艺碳密度补强增韧相

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MgO-C耐火材料抗折强度分布规律的研究

耐火材料 2012年第5期46卷 344-346页

作者：朱青友员文杰祝洪喜邓承继武汉科技大学耐火材料与高温陶瓷国家重点实验室培育基地湖北武汉430081

以两种不同碳含量的MgO-C耐火材料为研究对象,对试验测得的抗折强度数据采用Weibull函数进行统计分析,并结合试样的断口形貌研究了MgO-C耐火材料的抗折强度分布规律。结果表明:MgO-C耐火材料的抗折强度服从Weibull分布;增大材料的致密... 详细信息

以两种不同碳含量的MgO-C耐火材料为研究对象,对试验测得的抗折强度数据采用Weibull函数进行统计分析,并结合试样的断口形貌研究了MgO-C耐火材料的抗折强度分布规律。结果表明:MgO-C耐火材料的抗折强度服从Weibull分布;增大材料的致密度和石墨含量能够降低MgO-C耐火材料抗折强度的离散性,提高强度的可靠性。

关键词： MgO—C耐火材料抗折强度 Weibull模量显微结构

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氧化锡加入量对镁铝尖晶石浇注料性能的影响

耐火材料 2015年第5期49卷 335-338页

作者：员文杰商恒朱青友邓承继祝洪喜武汉科技大学省部共建耐火材料与冶金国家重点实验室湖北武汉430081

为了提高镁铝尖晶石浇注料的性能,研究了氧化锡加入量(质量分数分别为5%、7.5%和10%)对基质中分别采用板状刚玉T60和活性氧化铝CL370的镁铝尖晶石浇注料性能和显微结构的影响。结果表明:在镁铝尖晶石浇注料中添加氧化锡,随着氧化锡添加... 详细信息

为了提高镁铝尖晶石浇注料的性能,研究了氧化锡加入量(质量分数分别为5%、7.5%和10%)对基质中分别采用板状刚玉T60和活性氧化铝CL370的镁铝尖晶石浇注料性能和显微结构的影响。结果表明:在镁铝尖晶石浇注料中添加氧化锡,随着氧化锡添加量的增加,采用板状刚玉试样的显气孔率和烧后线变化率减小,常温抗折强度增大;而采用活性氧化铝试样则以氧化锡添加量为7.5%(w)时显气孔率和烧后线变化率最小,常温抗折强度最大。添加氧化锡的镁铝尖晶石浇注料在1 450℃煅烧5 h后均含有Mg2Sn O4、Ca Sn O3和Ca2Sn O4。可见,氧化锡在高温下与镁砂和铝酸钙水泥发生一系列原位反应提高组分之间的结合,并促进浇注料的烧结。

关键词：氧化锡镁铝尖晶石浇注料炼铜转炉