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《广西植物》被国际知名数据库ICI World of Journals和ICI Journals Master List收录
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《广西植物》 CAS CSCD 北大核心 2024年第3期F0002-F0002,共1页
日前,《广西植物》正式被波兰《哥白尼索引》(IC)旗下的两个知名数据库哥白尼索引期刊数据库(ICI World of Journals)和哥白尼索引精选数据库(ICI Journals Master List)全文收录,这是该期刊继被瑞典知名数据库(DOAJ)成功收录后的又一... 日前,《广西植物》正式被波兰《哥白尼索引》(IC)旗下的两个知名数据库哥白尼索引期刊数据库(ICI World of Journals)和哥白尼索引精选数据库(ICI Journals Master List)全文收录,这是该期刊继被瑞典知名数据库(DOAJ)成功收录后的又一大喜讯。 展开更多
关键词 数据库 World master ICI of 哥白尼
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OPD-ScanⅢ及IOL-Master 700测量白内障术前角膜曲率和水平角膜直径的比较
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作者 郭晓娜 陆惠 +2 位作者 寇豆 于璐 凌宇 《眼科新进展》 CAS 北大核心 2024年第5期391-395,共5页
目的比较OPD-ScanⅢ与IOL-Master 700在角膜曲率(平坦曲率K1与陡峭曲率K2)及水平角膜直径(WTW)测量上的差异性及一致性。方法选取2021年10月至2022年9月在航天中心医院眼科行白内障手术的患者268例328眼(右眼164例,左眼164例)。采用OPD-... 目的比较OPD-ScanⅢ与IOL-Master 700在角膜曲率(平坦曲率K1与陡峭曲率K2)及水平角膜直径(WTW)测量上的差异性及一致性。方法选取2021年10月至2022年9月在航天中心医院眼科行白内障手术的患者268例328眼(右眼164例,左眼164例)。采用OPD-ScanⅢ及IOL-Master 700仪器分别检测患者左右眼的K1、K2以及WTW值并进行分析比较。采用配对t检验进行参数比较;Pearson相关分析检测参数间的相关性;Bland-Altman以及组内相关系数(ICC)分析确定两种仪器相关参数测量的一致性。结果在左右眼参数的测量中,OPD-ScanⅢ测得的K1及K2值均大于IOL-Master 700,WTW值均低于IOL-Master 700的测量值,差异均有统计学意义(均为P<0.001)。OPD-ScanⅢ在左右眼中测得的K1、K2及WTW值与IOL-Master 700所测得的对应值均呈正相关,差异均有统计学意义(均为P<0.001)。两种仪器K1、K2及WTW值在95%一致性界限外的比例均在5%以内,但95%界限内差值绝对值均接近或超过了1.0 D,存在较大的临床偏差。ICC分析证实两种仪器左右眼测量K1及K2值一致性均极好(ICC>0.90)。两种仪器测得的WTW差值与K2值均显著相关(均为P<0.05)。WTW正偏差范围外有5例(83.33%)样本IOL-Master 700测得的K 2在47.03以上。结论OPD-ScanⅢ及IOL-Master 700在测量K1、K2及WTW上存在偏差,临床应用中不可互相替代。IOL-Master 700测得的WTW值大于OPD-ScanⅢ,当其测量的K2≥47.03时,所获得的WTW值参考价值可能有限。 展开更多
关键词 OPD-ScanⅢ IOL-master 700 角膜曲率 角膜水平直径
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Comparison of the Refraction Precision Results between Pentacam AXL and IOL Master 700 Using Universal II Barrett Formula after Cataract Surgery
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作者 Budiman   Tjokrovonco Ludwig Melino +1 位作者 Sugiarti Emmy Dwi Knoch Andrew Maximilian 《Open Journal of Ophthalmology》 2023年第1期1-12,共12页
Background: The availability of premium intraocular lenses (IOL), including toric, multifocal, and EDOF, has become very sophisticated and now demands accurate biometric measurement accuracy. The Pentacam AXL and IOL ... Background: The availability of premium intraocular lenses (IOL), including toric, multifocal, and EDOF, has become very sophisticated and now demands accurate biometric measurement accuracy. The Pentacam AXL and IOL Master 700 are often used for optical biometry and they are available in the market today. They can also be used to measure the parameters needed in the IOL calculation using the latest generation formulas, such as the Barett Universal II. Therefore, this study aims to compare the accuracy of refraction results between Pentacam AXL compared to IOL Master 700 after cataract surgery with the Barett Universal-II formula. Method: A total of 64 eyes from 64 patients who had a preoperative examination with IOL Master 700 and Pentacam AXL were included in this study. Parameters such as K, ACD, LT, WTW, and AL were then compared between the two tools. Prediction error values were also calculated and compared based on the difference between the Spherical equivalent (SE) of subjective refraction results after 4 weeks of surgery with their refractive prediction targets. Results: There was no statistically significant difference in the parameters measured from the two tools except ACD and WTW. Furthermore, LT was difficult to obtain on the Pentacam AXL due to penetration problems, as well as in patients with significant lens opacities. The percentage of error prediction values that reach ± 0.50 D on Pentacam AXL and IOL Master 700 was 70.3% and 73.5%, respectively. However, the average prediction error that was close to emmetropia with IOL Master 700 was greater compared to the other tool. Conclusion: Pentacam AXL has a fairly good accuracy for refraction prediction compared to IOL Master 700. However, it is still necessary to optimize its constants to obtain optimal results. 展开更多
关键词 Error Prediction BIOMETRY IOL master 700 Pentacam AXL
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A Trove of Masterpieces
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作者 ZHANG HUI 《China Today》 2023年第11期34-37,共4页
The special exhibition“The Greats of Six Centuries:Masterpieces from the Museo Nacional Thyssen-Bornemisza,”held in Shanghai provides profound insight into the evolution of Western culture,lifestyle,and social lands... The special exhibition“The Greats of Six Centuries:Masterpieces from the Museo Nacional Thyssen-Bornemisza,”held in Shanghai provides profound insight into the evolution of Western culture,lifestyle,and social landscapes over the 600 years. 展开更多
关键词 master LANDSCAPE pieces
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Confucius-The Storyofa Man Exemplary Masterof All Times-Confucius Culture Theme Exhibition
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作者 Sun Ruochen Zhang Honglei 《China & The World Cultural Exchange》 2023年第8期12-16,共5页
The exhibition presents the life of Confucius and the essence of his thoughts through plates,accompanied by replicas of related cultural objects and cultural creative products,with the purposeof helping local people u... The exhibition presents the life of Confucius and the essence of his thoughts through plates,accompanied by replicas of related cultural objects and cultural creative products,with the purposeof helping local people understand the origin of Confucianism and presenting the modern charm of traditional culture. 展开更多
关键词 TIMES CONFUCIUS master
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IOL Master 700与Lenstar LS900对高度近视合并白内障患者术前生物测量及人工晶状体计算的比较
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作者 陶露莎 高铃 +3 位作者 喻娟 冯英 陈爽 吴敏 《国际眼科杂志》 CAS 2024年第4期612-617,共6页
目的:比较IOL Master 700与Lenstar LS900对高度近视合并白内障患者术前眼生物测量的差异性、相关性、一致性及人工晶状体(IOL)度数计算的准确性。方法:回顾性研究。收集2021-03/2023-03于陆军特色医学中心眼科行白内障超声乳化联合IOL... 目的:比较IOL Master 700与Lenstar LS900对高度近视合并白内障患者术前眼生物测量的差异性、相关性、一致性及人工晶状体(IOL)度数计算的准确性。方法:回顾性研究。收集2021-03/2023-03于陆军特色医学中心眼科行白内障超声乳化联合IOL植入手术的高度近视合并白内障患者136例136眼,平均年龄57.38±8.08岁。根据眼轴长度(AL)将患者分为3组:A组(26 mm≤AL≤28 mm)41眼,B组(28 mm30 mm)52眼。术前分别使用两种仪器测量AL、平均角膜曲率(Km)、前房深度(ACD)、晶状体厚度(LT)和白到白距离(WTW)。所有患者均采用Barrett UniversalⅡ公式计算IOL度数,个性化选择适宜的预留屈光度,比较两种仪器的预测屈光误差(PE)和绝对屈光误差(AE)。结果:三组患者中Lenstar LS900测量的AL和ACD均大于IOL Master 700测量值(均P<0.05),且两种仪器测量AL的平均差值C组>B组>A组。两种仪器测量LT、Km与WTW值均无差异(均P>0.05)。两种仪器所得各组生物参数均具有正相关性(均r>0.9,P<0.05)且一致性较好(95%LoA范围较窄)。两种仪器计算的AE无差异(P>0.05),但IOL Master 700计算的PE小于Lenstar LS900(P<0.05),且前者远视偏移百分比更低。结论:在高度近视合并白内障患者中,Lenstar LS900测量AL值大于IOL Master 700,且该差异随着AL的增加而增大,两种仪器对IOL的计算均具有良好的预测性,但IOL Master 700术后屈光误差更小,远视偏移百分比更低。 展开更多
关键词 IOL master 700 Lenstar LS900 高度近视 白内障 生物测量 眼轴 人工晶状体 Barrett UniversalⅡ
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Strategies for Improving the Effectiveness of Professional Practice for Full-Time Professional Master Degree Postgraduate in Mineral Processing Engineering
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作者 Jiushuai Deng Juan Hu +3 位作者 Zhiqiang Xu Weidong Wang Zhongyi Bai Tingting Hu 《Journal of Contemporary Educational Research》 2023年第1期27-32,共6页
In order to gain practical experience and hands-on skills,full-time professional master degree postgraduate in mineral processing engineering should engage in professional practices.Nonetheless,a series of problems,in... In order to gain practical experience and hands-on skills,full-time professional master degree postgraduate in mineral processing engineering should engage in professional practices.Nonetheless,a series of problems,including insufficient time for practice,low management level,inadequate implementation of the double-supervisor system,and poor results of professional practice,has reduced the effectiveness of professional practice.In view of the aforementioned problems and the characteristics of the discipline,this paper proposes several strategies for improving the effectiveness of professional practice for postgraduates in mineral processing engineering. 展开更多
关键词 Mineral processing engineering FULL-TIME Application-oriented master’s degree Professional practice
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On Master Tanxu’s Thought of the Middle Way
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作者 GUO Yancheng GUO Jintong 《Cultural and Religious Studies》 2023年第6期253-257,共5页
This paper discusses Master Tanxu’s Thought of Middle Way from three aspects:interpreting the Middle Way with the Tiantai Sect’s thought of“Three Truths as a Unity”(三諦圓融),discussing“the Truth of the First Mea... This paper discusses Master Tanxu’s Thought of Middle Way from three aspects:interpreting the Middle Way with the Tiantai Sect’s thought of“Three Truths as a Unity”(三諦圓融),discussing“the Truth of the First Meaning of the Middle Way”(中道第一義諦)from the relationship between“the One Mind”and the Middle Way,and discussing gradations of practice of the Middle Way. 展开更多
关键词 master Tanxu the Thought of the Middle Way the Truth of the First Meaning of the Middle Way the One Mind
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IOLmaster700与Lenstar测量青光眼合并白内障患者眼部生物参数的比较
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作者 张婧 孙素芳 《中文科技期刊数据库(文摘版)医药卫生》 2024年第4期0009-0011,共3页
比较IOL Master 700与Lenstar在测量青光眼合并白内障患者的眼轴、角膜中央厚度以及前房深度等眼部参数的差异性、相关性和一致性。方法 选取2023年5-8月在复旦大学附属眼耳鼻喉科医院拟进行超声乳化人工晶状体植入联合房角分离术的患... 比较IOL Master 700与Lenstar在测量青光眼合并白内障患者的眼轴、角膜中央厚度以及前房深度等眼部参数的差异性、相关性和一致性。方法 选取2023年5-8月在复旦大学附属眼耳鼻喉科医院拟进行超声乳化人工晶状体植入联合房角分离术的患者61例(100只眼),分别进行IOL Master 700和Lenstar检查,其中每只受试眼IOL Master 700自动测量五次,Lenstar测量三次,分别取平均值。配对t检验和Pearson相关性分析分别对两种机器测得AL 、CCT、 AQD进行差异性和相关性分析。Bland-Altman分析IOL Master 700和Lenstar测量的AL 、CCT、AQD的一致性。结果 IOL Master 700与Lenstar测量所得的AL无显著统计学差异(P>0.05),CCT及AQD均有显著统计学差异(P<0.05)。通过Pearson相关分析,两种仪器所测的AL、CCT、AQD之间均有较好的相关性(r=0.960~1.000,p<0.001),且经Bland-Altman分析,这两种仪器在测量AL、CCT、 AQD等眼部生物参数时一致性较好。结论 IOL Master 700与Lenstar在测量眼轴、角膜中央厚度和前房深度时,有高度的一致性和相关性,临床上可以相互替代。 展开更多
关键词 IOL master700 LENSTAR 眼轴长度 角膜中央厚度 前房深度
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莫廷ColomboIOL与卡尔蔡司IOLmaster500眼轴检出率的对比研究
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作者 卢春明 《中国科技期刊数据库 医药》 2024年第4期0109-0112,共4页
对比研究莫廷 Colombo IOL眼科光学生物测量仪与卡尔蔡司IOL master 500眼科光学生物测量仪对行白内障术前检查的年龄相关性白内障患者的眼轴检出率。方法 选取我院于2022年1月至2023年5月期间内接收的需要进行白内障术前检查的年龄相... 对比研究莫廷 Colombo IOL眼科光学生物测量仪与卡尔蔡司IOL master 500眼科光学生物测量仪对行白内障术前检查的年龄相关性白内障患者的眼轴检出率。方法 选取我院于2022年1月至2023年5月期间内接收的需要进行白内障术前检查的年龄相关性白内障患者200名(388只眼)作为本次实验的测量对象,分别适用莫廷 Colombo IOL眼科光学生物测量仪与卡尔蔡司IOL master 500眼科光学生物测量仪对这200名年龄相关性白内障患者进行眼轴检测,并计算两种仪器的眼轴检出率,使用统计学方法做差异性分析。结果 在388眼中,莫廷 Colombo IOL眼科光学生物测量仪可以测出331只眼睛的眼轴数据,检出率为85.31%,卡尔蔡司IOL master 500眼科光学生物测量仪可以测出295只眼睛的眼轴数据,检出率为76.03%,两组数据对比检出率差异具有统计学意义,p<0.05。结论 在对年龄相关性白内障患者行白内障术前检查中,莫廷 Colombo IOL眼科光学生物测量仪的眼轴检出率高于卡尔蔡司IOL master 500眼科光学生物测量仪的眼轴检出率。 展开更多
关键词 莫廷 Colombo IOL眼科光学生物测量仪 卡尔蔡司IOL master 500眼科光学生物测量仪 白内障
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《牛津大学章程》中学位名称汉译简论——兼评北大版《大学章程》第四卷译本对学位名称-“Master of Arts”的翻译
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作者 喻海燕 《齐齐哈尔大学学报(哲学社会科学版)》 2013年第5期117-119,共3页
北京大学出版社出版的张国友主编的《大学章程》第四卷是《牛津大学章程》的汉译本。此译本将学位"Master of Arts"译成"文理硕士"似有值得商榷之处。本文从译本对学位名称-"Master of Arts"的翻译、&quo... 北京大学出版社出版的张国友主编的《大学章程》第四卷是《牛津大学章程》的汉译本。此译本将学位"Master of Arts"译成"文理硕士"似有值得商榷之处。本文从译本对学位名称-"Master of Arts"的翻译、"Master of Arts"的汉译举隅、牛津大学学位-"Master of Arts"解析和牛津大学学位-"Master of Arts"的汉译技巧等四方面对此译本的翻译加以评论,并提出了一些思考。 展开更多
关键词 master of ARTS 张国友 牛津大学章程 汉译
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Mind Master引导下的费曼学习法在骨科实习中的应用研究 被引量:2
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作者 董军 张格林 +4 位作者 孙园 张旭艳 李玺 黄思华 张纯 《中国继续医学教育》 2023年第7期84-88,共5页
目的 探究Mind Master引导下的费曼学习法在骨科实习中的应用研究。方法 于2016年1月—2021年12月纳入西安交通大学第二附属医院骨三科实习医生分为传统教学法组(102名)和费曼学习法组(136名)。评估两组考核成绩和迷你临床演练评估(mini... 目的 探究Mind Master引导下的费曼学习法在骨科实习中的应用研究。方法 于2016年1月—2021年12月纳入西安交通大学第二附属医院骨三科实习医生分为传统教学法组(102名)和费曼学习法组(136名)。评估两组考核成绩和迷你临床演练评估(mini clinical evaluation exercise,Mini-CEX)量表结果。结果 费曼学习法组学生在理论成绩、实践成绩方面均显著优于传统教学法组,差异有统计学意义(P <0.05);在MiniCEX量表评估问诊、查体、专业态度、临床判断、整体临床评价以及评价人满意度方面显著优于传统教学法组,差异有统计学意义(P <0.05)。而在Mini-CEX量表评估的沟通技能、组织效能、被评价人满意度两组差异无统计学意义(P> 0.05)。结论 利用Mind Master归纳总结的费曼学习法教学模式能实习医生的理论和实践水平。 展开更多
关键词 费曼学习法 思维导图 骨科 教学 实习 规范化培训 临床
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基于SVR和BP神经网络算法通过IOL Master 700测量数据来预测白内障术后CW弦
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作者 李晨 《国际眼科杂志》 CAS 北大核心 2023年第12期2081-2086,共6页
目的:通过IOL Master 700观察白内障手术前后Chang-Warning弦(CW弦)的变化,并利用术前数据和人工智能预测模型预测术后CW弦。方法:研究对象为304例白内障患者,分析其术前及术后的IOL Master 700测量数据,包括散光矢量值、角膜平均曲率... 目的:通过IOL Master 700观察白内障手术前后Chang-Warning弦(CW弦)的变化,并利用术前数据和人工智能预测模型预测术后CW弦。方法:研究对象为304例白内障患者,分析其术前及术后的IOL Master 700测量数据,包括散光矢量值、角膜平均曲率、眼轴长度、前房深度、晶状体厚度、角膜中央厚度、白到白距离、浦肯野反射Ⅰ像相对于角膜中心的位置和瞳孔中心的位置、CW弦等。研究建立了基于SVR算法和BP神经网络算法的预测模型,通过术前CW弦及眼部生物参数来预测术后CW弦。结果:相比于白内障手术前,手术后左、右眼CW弦X分量向颞侧有轻微偏移,Y分量变化不大。使用术前CW弦和其他术前眼部生物参数作为输入数据,相比于BP神经网络,SVR模型能够更准确的对术后CW弦的X分量和Y分量做出预测。结论:CW弦可以用各种生物测量仪器、角膜地形图仪器或断层摄像仪器在同轴固定光下直接测量。使用SVR算法能够在白内障手术前较精准的对术后CW弦进行预测。 展开更多
关键词 alpha角 KAPPA角 Chang-Waring弦(CW弦) 深度学习 白内障 SVR算法 BP神经网络算法 IOL master 700
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Analysis on the master event method and precise location of 1997 Jiashi strong earthquake swarm in western China 被引量:9
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作者 周仕勇 许忠淮 +2 位作者 韩京 许洪新 努尔尼沙 《Acta Seismologica Sinica(English Edition)》 EI CSCD 1999年第3期285-291,共7页
关键词 JIASHI strong earthquake SWARM master EVENT LOCATION
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Comparison of OA-2000 and IOL Master 500 using in cataract patients with high myopia 被引量:11
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作者 Ya-Li Du Geng Wang +5 位作者 Hui-Chun Huang Li-Yu Lin Chuang Jin Li-Fang Liu Xiu-Ru Liu Ming-Zhi Zhang 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2019年第5期844-847,共4页
This study was designed to compare optical biometry measurements and predicted refraction in cataract patients with high myopia [axial length(AL) ≥26 mm] using OA-2000 and IOL Master 500. Ocular biometry measurements... This study was designed to compare optical biometry measurements and predicted refraction in cataract patients with high myopia [axial length(AL) ≥26 mm] using OA-2000 and IOL Master 500. Ocular biometry measurements were performed using both biometers before surgery. Uneventful cataract surgery was performed in all patients. Postoperative manifest refraction was obtained 3 wk after surgery or later. A total of 67 eyes were examined. The AL, keratometry(K), and anterior chamber depth(ACD) of the two biometers showed excellent agreement. Predicted errors were similar and a strong positive correlation was observed(r=0.909). Out of 21 eyes(31.34%) with unsuccessful AL readings using the IOL Master 500, 20 eyes of them could be measured using OA-2000. Therefore, the biometric parameters measured by the two biometers showed good agreement. However, OA-2000 had a lower AL measurement failure rate. 展开更多
关键词 OA-2000 IOL master 500 BIOMETRY measurement IOL power calculation high MYOPIA CATARACT
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Preparation of Al-Sr Master Alloy in Aluminum Electrolysis Cell 被引量:6
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作者 杨宝刚 于佩志 +1 位作者 李冰 邱竹贤 《Rare Metals》 SCIE EI CAS CSCD 2000年第3期192-196,共4页
Al Sr master alloy was prepared by using liquid aluminum cathode and a mixture of Na 3AlF 6 - SrCO 3 as the basic molten salt electrolyte in a laboratory electrolysis cell.The effects of electrolyte composition,electr... Al Sr master alloy was prepared by using liquid aluminum cathode and a mixture of Na 3AlF 6 - SrCO 3 as the basic molten salt electrolyte in a laboratory electrolysis cell.The effects of electrolyte composition,electrolysis temperature,cathodic current density and the electrolytic duration on Sr content of Al Sr alloy were studied.Through laboratory experiments,the parameters for smooth electrolytic reaction were proposed. 展开更多
关键词 Al Sr master alloy ELECTROLYSIS Strontium content
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INFLUENCE OF Al-5Ti-1B MASTER ALLOY ON MICROSTRUCTURE AND DAMPING CAPACITY OF ZA27 ALLOY 被引量:5
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作者 Zhang, Zhongming Wang, Jincheng +3 位作者 Lu, Yili Song, Guangsheng Yang, Gencang Zhou, Yaohe 《中国有色金属学会会刊:英文版》 EI CSCD 1998年第3期145-149,共5页
1INTRODUCTIONThedampingcapacityofamaterialisameasureoftheenergythatisdissipatedinthematerialduringmechanical... 1INTRODUCTIONThedampingcapacityofamaterialisameasureoftheenergythatisdissipatedinthematerialduringmechanicalvibrationundercyc... 展开更多
关键词 ZA27 ALLOY Al 5Ti 1B master ALLOY MODIFICATION DAMPING capacity DAMPING mechanism
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Aluminothermic Reduction of K_2ZrF_6 for Preparation of Al-Zr Master Alloy 被引量:2
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作者 Rajagopalan P.K., Sharma I.G. and Krishnan T.S. Materials Processing Division, Bhabha Atomic Research Centre, Mumbai 400085, India Bose D.K. Uranium Extraction Division, Bhabha Atomic Research Centre, Mumbai 400085, India 《Rare Metals》 SCIE EI CAS CSCD 1999年第2期40-43,共4页
luminothermicReductionofK2ZrF6forPreparationofAlZrMasterAloyRajagopalanP.K.,SharmaI.G.andKrishnanT.S.Materi... luminothermicReductionofK2ZrF6forPreparationofAlZrMasterAloyRajagopalanP.K.,SharmaI.G.andKrishnanT.S.MaterialsProcesingDivis... 展开更多
关键词 GRAIN REFINEMENT master ALLOY ALLOY YIELD ZIRCONIUM recovery
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Effect of cooling rate on morphology and type of vanadium-containing phases in Al-10V master alloy 被引量:2
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作者 Qing-feng Zhu Yi Meng +3 位作者 Yan-lei Kang Shu-ping Kong Yang-peng Ou Yu-bo Zuo 《China Foundry》 SCIE 2019年第5期300-306,共7页
Effects of cooling rates on the morphology, sizes and species of primary vanadium-containing phases in Al-10V master alloys were investigated. The results show that the primary vanadium-containing phases with differen... Effects of cooling rates on the morphology, sizes and species of primary vanadium-containing phases in Al-10V master alloys were investigated. The results show that the primary vanadium-containing phases with different morphologies and compositions present in Al-10V master alloys at different cooling rates with the pouring temperature of 1,170 °C. When the Al-10V master alloy is solidified in the refractory mold at a cooling rate of 2 °C·s-1, the vanadium-containing phases are mainly plate-like Al10V phases, with the average size of 100.0 μm in the center and 93.2 μm at the edge of the ingot. When the master alloy is solidified in the graphite mold at a cooling rate of 24.3 °C·s-1, the primary vanadium-containing phases are dendritic Al3V phases, with the average length of 297.0 μm for the first dendrite in the center and 275.0 μm at the edge of the ingot. The secondary dendrite arm spacing (SDAS) is 9.5 μm in the center and 9.3 μm at the edge of the ingot, respectively. When the solidification is carried out in the copper mould at a cooling rate of 45.7 °C·s-1, the primary vanadium-containing phases are also Al3V phases but with smaller size, compared with that prepared at the cooling rate of 24.3 °C·s-1. As a result, the average length is 190.0 μm for the first dendrite in the center and 150.0 μm at the edge of the ingot. The SDAS is 9.8 μm in the center and 4.4 μm at the edge of the ingot, respectively. 展开更多
关键词 Al-V master alloy cooling rate vanadium-containing phase SOLIDIFICATION
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STUDY OF THE NUCLEATION MECHANISM OF α-Al GRAINS AFTER ADDITION OF Al-Ti-B MASTER ALLOYS 被引量:2
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作者 X.F.Liu X.F.Bian +2 位作者 X.G.Qi M.Thompson J.JMa 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1998年第3期157-162,共6页
Nucleation sites of α-Al grains after addition of an Al-Ti-B master alloy into pure aluminium have been investigated using EPMA. The results show that either TiAl3 or boride particales can nucleate α-Al grains. But ... Nucleation sites of α-Al grains after addition of an Al-Ti-B master alloy into pure aluminium have been investigated using EPMA. The results show that either TiAl3 or boride particales can nucleate α-Al grains. But the number of TiAl3 nucleants is reduced with the holding time prolonged and the boride-nuclei are increasing gradually. Based on these results, a new refining method, adding molten Al-Ti-B into commercially pure aluminium, which has a quicker and better refining efficiency is presented. 展开更多
关键词 AL-TI-B master alloy GRAIN REFINEMENT NUCLEATION mechanism α-Al nucleant
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