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欠发达民族社区特困人口移迁扶贫开发与安置问题实证研究——以贵州省三个民族社区为例 被引量:3
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作者 杨军昌 丁仁船 罗凌 《贵州民族学院学报(哲学社会科学版)》 2003年第2期51-55,共5页
少数民族特困人口问题是关系到我国人口与可持续发展战略和民族团结与共同发展繁荣的重要而特 殊的问题。由于历史、自然生产力发展水平等因素影响,贵州仍有一定数量的少数民族特困人口。对 这些特殊群体解决温饱,走向富裕,实现可持续... 少数民族特困人口问题是关系到我国人口与可持续发展战略和民族团结与共同发展繁荣的重要而特 殊的问题。由于历史、自然生产力发展水平等因素影响,贵州仍有一定数量的少数民族特困人口。对 这些特殊群体解决温饱,走向富裕,实现可持续发展必须结合地情寻求多种途径予与解决。本文通过 对贵州三个少数民族社区移迁安置状况进行了实地调查,并进行分析研究。 展开更多
关键词 民族社区 特困人口 移迁扶贫开发 贵州
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论科技移迁导致的后发优势对经济的推动作用 被引量:1
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作者 贺雪娟 《湖南经济管理干部学院学报》 2002年第2期3-4,共2页
原有科技水平落后是发展中国家产生后发优势的主要原因 ,科技水平的差异分布是推动科技移迁的内在动力 ,加入世贸组织为科技向我国移迁提供了机遇 ,充分发挥自身的比较优势 ,进一步完善市场机制 ,优化经济环境是吸引世界先进科技水平向... 原有科技水平落后是发展中国家产生后发优势的主要原因 ,科技水平的差异分布是推动科技移迁的内在动力 ,加入世贸组织为科技向我国移迁提供了机遇 ,充分发挥自身的比较优势 ,进一步完善市场机制 ,优化经济环境是吸引世界先进科技水平向我国移迁、提高我国经济竞争实力的有效措施。本文引入了科技水平场的概念 ,试图用场论的有关方法来分析科技移迁中的某些问题。 展开更多
关键词 后发优势 科技移迁 经济发展 经济竞争力 科技水平差异分布
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长安街西延管线迁改移工程设计与实施
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作者 刘作坤 罗希明 +1 位作者 吕冬梅 崔嘉婧 《工程建设与设计》 2024年第19期51-54,共4页
长安街西延管线迁改移工程的设计和实施,兼顾了市政规划和新首钢园区规划,对与新首钢大桥相干涉的电气架空管廊入地,将首钢园区电信、给排水拆改管线与市政规划管线统一设计。论文介绍了工程设计、实施过程中遇到的困难和问题,以及采取... 长安街西延管线迁改移工程的设计和实施,兼顾了市政规划和新首钢园区规划,对与新首钢大桥相干涉的电气架空管廊入地,将首钢园区电信、给排水拆改管线与市政规划管线统一设计。论文介绍了工程设计、实施过程中遇到的困难和问题,以及采取的技术措施和方法。 展开更多
关键词 市政规划 地下管线 长安街西延
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贵州农村特困人口移民搬迁及扶贫开发 被引量:5
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作者 杨军昌 《人口与经济》 CSSCI 北大核心 2003年第4期8-13,共6页
本文站在我国 2 1世纪扶贫攻坚战略与可持续发展高度 ,对贵州所开展的特殊扶贫方式———移民搬迁扶贫开发在效益、经验和存在问题上进行了总结和研究。认为移民搬迁扶贫开发是解决贵州农村特困人口温饱、走向发展的一条有效途径 ,并结... 本文站在我国 2 1世纪扶贫攻坚战略与可持续发展高度 ,对贵州所开展的特殊扶贫方式———移民搬迁扶贫开发在效益、经验和存在问题上进行了总结和研究。认为移民搬迁扶贫开发是解决贵州农村特困人口温饱、走向发展的一条有效途径 ,并结合贵州省情对 2 1世纪初贵州特困人口移迁安置的指导思想、原则、搬迁重点区域。 展开更多
关键词 贵州 农村 特困人口 移迁安置 扶贫开发
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RTV硅橡胶涂层耐污闪性能及憎水迁移特性 被引量:6
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作者 关志成 于素竹 贾志东 《绝缘材料通讯》 1994年第6期21-26,共6页
在绝缘子表面涂覆一层RTV硅橡胶薄膜.能显著提高绝缘子的耐污闪能力,其原因主要在于硅橡胶材料的表面憎水性及其憎水迁移特性.本文在洁净干燥、淋雨、凝露、湿污等状态下试验并比较了有、无涂层绝缘子的闪络电压,研究了温度、灰密... 在绝缘子表面涂覆一层RTV硅橡胶薄膜.能显著提高绝缘子的耐污闪能力,其原因主要在于硅橡胶材料的表面憎水性及其憎水迁移特性.本文在洁净干燥、淋雨、凝露、湿污等状态下试验并比较了有、无涂层绝缘子的闪络电压,研究了温度、灰密、盐密、涂层厚度、附灰频度、老化时间等因素对憎水迁移特性的影响,并分析讨论了硅橡校材料产生憎水迁移特性的机理. 展开更多
关键词 污秽 憎水性移迁 硅橡胶
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试论英语习得中的母语迁移问题 被引量:6
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作者 王燕 《浙江青年专修学院学报》 2007年第1期42-43,共2页
在第二语言的习得过程中,母语的迁移能力是不可忽视的。迁移可分为正迁移和负迁移,分别体现在英语语音、词汇、语法和文化上。我们在英语习得中应该积极发挥母语正迁移作用和用背诵输入法减少负迁移作用,为学好英语提供一个重要的方法。
关键词 英语习得 母语移迁 背诵输入
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季铵盐型阳离子表面活性剂的液膜迁移(Ⅱ) 被引量:1
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作者 符爱云 孙德志 +1 位作者 尹宝霖 魏西莲 《表面活性剂工业》 1999年第2期14-17,共4页
用电导法测定了不同温度下十六烷基三甲基溴化铵在以氯仿、二氯甲烷为膜相时的一系列迁移动力学曲线。
关键词 液膜移迁 阳离子型 表面活性剂 季铵盐
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托达罗人口迁移模型与中国“民工潮”问题的分析 被引量:1
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作者 郑兴明 《云南行政学院学报》 2004年第1期123-125,共3页
托达罗的人口迁移模型理论旨在解释发展中国家广泛存在的从农村向城市移民的原因。利用托达罗人口迁移模型分析当前我国存在的“民工潮”现象具有现实指导意义 ,只要存在城乡预期收入差距 ,都必然会出现“民工潮”现象。解决此问题 ,一... 托达罗的人口迁移模型理论旨在解释发展中国家广泛存在的从农村向城市移民的原因。利用托达罗人口迁移模型分析当前我国存在的“民工潮”现象具有现实指导意义 ,只要存在城乡预期收入差距 ,都必然会出现“民工潮”现象。解决此问题 ,一要大力发展劳动密集型产业 ;二要加快城镇化步伐 ;三要进行农业产业化经营。根本解决民工潮问题 ,还是要增加农民收入和就业 。 展开更多
关键词 托达罗人口移迁模型 民工潮 增加农民收入 就业
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可平台迁移的最坏执行时间分析
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作者 刘育芳 张立臣 《计算机工程与设计》 CSCD 北大核心 2006年第8期1317-1320,共4页
当前的很多最坏执行时间分析工具都是针对特定的编程语言或特定的编译器的,因而缺乏平台间的迁移性,从而不能被广泛使用。介绍了一种基于Java字节码的可平台迁移的最坏执行时间分析方法。该分析方法包括两方面:一是对字节码(java byteco... 当前的很多最坏执行时间分析工具都是针对特定的编程语言或特定的编译器的,因而缺乏平台间的迁移性,从而不能被广泛使用。介绍了一种基于Java字节码的可平台迁移的最坏执行时间分析方法。该分析方法包括两方面:一是对字节码(java bytecode)的高层分析,提取出程序数据流和控制流信息;二是对Java虚拟机的底层分析,获得虚拟机的时间模型。最后这两种分析结合得到程序的最坏执行时间。同时还探讨了将来的研究方向。 展开更多
关键词 实时系统 最坏执行时间分析 的最坏执行时间分析 JAVA字节码 JAVA虚拟机
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任务型语言教学中任务迁移现象研究
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作者 高海龙 《温州大学学报(社会科学版)》 2020年第4期62-71,共10页
以Benson的研究为基础,考察学习者经过培训后,是否能将任务完成能力迁移到新的任务中,结果发现,低水平学习者完成同种任务比完成不同种任务有更高的准确性和更快的反应速度,这反映了任务迁移的现象,而高水平学习者却没有体现出这方面特... 以Benson的研究为基础,考察学习者经过培训后,是否能将任务完成能力迁移到新的任务中,结果发现,低水平学习者完成同种任务比完成不同种任务有更高的准确性和更快的反应速度,这反映了任务迁移的现象,而高水平学习者却没有体现出这方面特点。结合Krashen的输入假设理论“i+1”公式,提出“可迁移的任务”概念,并探讨相关研究结果对任务型语言教学学习任务的选择和安排的启示。 展开更多
关键词 任务型语言教学 的任务 二语学习者 语言水平
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Improvement of High-Speed Detection Algorithm for Nonwoven Material Defects Based on Machine Vision 被引量:2
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作者 LI Chengzu WEI Kehan +4 位作者 ZHAO Yingbo TIAN Xuehui QIAN Yang ZHANG Lu WANG Rongwu 《Journal of Donghua University(English Edition)》 CAS 2024年第4期416-427,共12页
Defect detection is vital in the nonwoven material industry,ensuring surface quality before producing finished products.Recently,deep learning and computer vision advancements have revolutionized defect detection,maki... Defect detection is vital in the nonwoven material industry,ensuring surface quality before producing finished products.Recently,deep learning and computer vision advancements have revolutionized defect detection,making it a widely adopted approach in various industrial fields.This paper mainly studied the defect detection method for nonwoven materials based on the improved Nano Det-Plus model.Using the constructed samples of defects in nonwoven materials as the research objects,transfer learning experiments were conducted based on the Nano DetPlus object detection framework.Within this framework,the Backbone,path aggregation feature pyramid network(PAFPN)and Head network models were compared and trained through a process of freezing,with the ultimate aim of bolstering the model's feature extraction abilities and elevating detection accuracy.The half-precision quantization method was used to optimize the model after transfer learning experiments,reducing model weights and computational complexity to improve the detection speed.Performance comparisons were conducted between the improved model and the original Nano Det-Plus model,YOLO,SSD and other common industrial defect detection algorithms,validating that the improved methods based on transfer learning and semi-precision quantization enabled the model to meet the practical requirements of industrial production. 展开更多
关键词 defect detection nonwoven materials deep learning object detection algorithm transfer learning halfprecision quantization
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Slope displacement prediction based on multisource domain transfer learning for insufficient sample data
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作者 Zheng Hai-Qing Hu Lin-Ni +2 位作者 Sun Xiao-Yun Zhang Yu Jin Shen-Yi 《Applied Geophysics》 SCIE CSCD 2024年第3期496-504,618,共10页
Accurate displacement prediction is critical for the early warning of landslides.The complexity of the coupling relationship between multiple influencing factors and displacement makes the accurate prediction of displ... Accurate displacement prediction is critical for the early warning of landslides.The complexity of the coupling relationship between multiple influencing factors and displacement makes the accurate prediction of displacement difficult.Moreover,in engineering practice,insufficient monitoring data limit the performance of prediction models.To alleviate this problem,a displacement prediction method based on multisource domain transfer learning,which helps accurately predict data in the target domain through the knowledge of one or more source domains,is proposed.First,an optimized variational mode decomposition model based on the minimum sample entropy is used to decompose the cumulative displacement into the trend,periodic,and stochastic components.The trend component is predicted by an autoregressive model,and the periodic component is predicted by the long short-term memory.For the stochastic component,because it is affected by uncertainties,it is predicted by a combination of a Wasserstein generative adversarial network and multisource domain transfer learning for improved prediction accuracy.Considering a real mine slope as a case study,the proposed prediction method was validated.Therefore,this study provides new insights that can be applied to scenarios lacking sample data. 展开更多
关键词 slope displacement multisource domain transfer learning(MDTL) variational mode decomposition(VMD) generative adversarial network(GAN) Wasserstein-GAN
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济宁太白楼移建济州城上时间考
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作者 王胜运 《济宁学院学报》 2017年第6期122-124,共3页
《济宁巿志》等著述,把济宁太白楼移建济州南城上的时间确定为明洪武二十四年(1391年),是个明显错误。狄崇在洪武四年(1371年)"甃城于砖"时,只是对已迁城上之楼进行了重修。早此一百多年,元至元二十二年(1285年),监州冀德方... 《济宁巿志》等著述,把济宁太白楼移建济州南城上的时间确定为明洪武二十四年(1391年),是个明显错误。狄崇在洪武四年(1371年)"甃城于砖"时,只是对已迁城上之楼进行了重修。早此一百多年,元至元二十二年(1285年),监州冀德方就主持移迁并重修太白楼于济州南城上。 展开更多
关键词 济宁太白楼 移迁 济州城 至元二十二年 冀德方
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藏区水库移民过程中宗教设施迁建的政策研究 被引量:5
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作者 李锦 耿静 罗凉昭 《西南民族大学学报(人文社会科学版)》 CSSCI 北大核心 2009年第7期16-19,共4页
水库移民搬迁是经济建设中的现实问题。藏区水库移民过程中宗教设施迁建又是一个现实而敏感的问题。我们以大渡河上游,位于阿坝藏族羌族自治州境内的双江口电站为例,对相关问题进行了研究。并且,鉴于大部分藏族地区的宗教设施迁建问题... 水库移民搬迁是经济建设中的现实问题。藏区水库移民过程中宗教设施迁建又是一个现实而敏感的问题。我们以大渡河上游,位于阿坝藏族羌族自治州境内的双江口电站为例,对相关问题进行了研究。并且,鉴于大部分藏族地区的宗教设施迁建问题性质及程序基本相同,这一研究的结果也具有适应性。 展开更多
关键词 少数民族地区 水库 宗教文化设施 移迁建设
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魏家地矿综放回采巷道矿压显现规律研究 被引量:2
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作者 李树刚 余锋 《矿山压力与顶板管理》 北大核心 2002年第4期27-29,共3页
采用综合机械化放顶煤技术开采富含瓦斯厚煤层时 ,工作面回采巷道布置有其特殊性。通过建立魏家地矿西一采区 1 1 0综放面回采巷道矿压观测系统 ,分析了观测结果及巷道变形原因 ,从而得出了放顶煤综采过程中矿压显现的基本规律。
关键词 回采巷道 矿压显现规律 移迁 综放工作面 巷道变形
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Migration and Transformation of Coated Controlled Release Nitrogen in Soil under Co-situs Application Mode 被引量:11
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作者 肖强 王甲辰 +4 位作者 左强 张琳 刘宝存 赵同科 邹国元 《Agricultural Science & Technology》 CAS 2009年第6期144-149,共6页
By using field trials, the migration and transformation of coated controlled release nitrogen (YZS80) in soil under the co-situs application mode were studied. The results indicated that YZS80 nitrogen dissolved out... By using field trials, the migration and transformation of coated controlled release nitrogen (YZS80) in soil under the co-situs application mode were studied. The results indicated that YZS80 nitrogen dissolved out in average speed of about 0.4%/d and 32% totally in 80 d compared with common compound fertUizer. For YZS80, in the vertical downward direction of application points, urea nitrogen content increased significantly (P 〈0.05) in the 45 -80 d and the 30 -60 cm soil layers; nitrate nitrogen content was little change range and in moderate (10 -100 mg/kg) in 0 -80 d and 10 -60 cm soil layers, but increased significantly ( P 〈0.05) 45 -80 d compared to 0 -45 d; ammonium nitrogen content was significant lower (P〈0.05) before 45 d in 10 -30 cm soil layers, but significant higher(P〈0.05) after 45 d in 10 -60 cm soil layers; NO3^- -N/NH4^+ -N meets gradually the needs of the crop with the extension of time. Under the co-situs application mode, the possibility of burning root and salt injury and loss dsk of nitrate leaching is a significant reduction. 展开更多
关键词 Co-situs application Slow/controlled release fertilizer MIGRATION TRANSFORMATION
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Effects of direct current electric field on corrosion behaviour of copper, Cl- ion migration behaviour and dendrites growth under thin electrolyte layer 被引量:11
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作者 黄华良 潘志权 +1 位作者 郭兴蓬 邱于兵 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第1期285-291,共7页
Effect of direct current electric field (DCEF) on corrosion behaviour of copper printed circuit board (PCB-Cu), Cl-ion migration behaviour, dendrites growth under thin electrolyte layer was investigated using pote... Effect of direct current electric field (DCEF) on corrosion behaviour of copper printed circuit board (PCB-Cu), Cl-ion migration behaviour, dendrites growth under thin electrolyte layer was investigated using potentiodynamic polarization and scanning electron microscopy (SEM) with energy dispersive spectrometer (EDS). Results indicate that DCEF decreases the corrosion of PCB-Cu;Cl-ions directionally migrate from the negative pole to the positive pole, and enrich on the surface of the positive pole, which causes serious localized corrosion; dendrites grow on the surface of the negative pole, and the rate and scale of dendrite growth become faster and greater with the increase of external voltage and exposure time, respectively. 展开更多
关键词 COPPER DENDRITES MIGRATION direct current electric field thin electrolyte layer copper printed circuit board
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Migration and transfer of chromium in soil-vegetable system and associated health risks in vicinity of ferro-alloy manufactory 被引量:6
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作者 廖映平 王振兴 +3 位作者 杨志辉 柴立元 陈建群 袁平夫 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第11期2520-2527,共8页
Study was carried out to analyze the distribution and migration patterns,soil-to-plant transfer and potential health risks of chromium in soil-vegetable system in areas near a ferro-alloy manufactory in Hunan province... Study was carried out to analyze the distribution and migration patterns,soil-to-plant transfer and potential health risks of chromium in soil-vegetable system in areas near a ferro-alloy manufactory in Hunan province.The results show that soils near sewer outlet,sewer channel and in control area are averaged 2 239.5,995.33 and 104.9 mg/kg,respectively.The total Cr has a relative accumulation in soil depth of 200-400 mm near the sewer outlet,mainly enriches in the surface layer(0-200 mm) near the sewer channel and decreases gradually in unpolluted soils.The differential concentration level of enrichment between layers is little.The results also indicate that the three vegetables of celery,lettuce and Chinese cabbage are able to convert the potentially toxic Cr(Ⅵ) species into the non-toxic Cr(Ⅲ) species,and the chromium contents in the edible parts of the vegetables are averaged 11.95 mg/kg.The transfer factors of the three vegetables follow the order:Chinese cabbage lettuce celery.The estimated total daily intake of chromium substantially exceeds the dietary allowable value,which may pose health risks to local population. 展开更多
关键词 heavy metal CHROMIUM MIGRATION transfer factor health risk soil VEGETABLE
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14W X-Band AlGaN/GaN HEMT Power MMICs 被引量:5
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作者 陈堂胜 张斌 +3 位作者 任春江 焦刚 郑维彬 陈辰 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第6期1027-1030,共4页
The development of an AIGaN/GaN HEMT power MMIC on SI-SiC designed in microstrip technology is pres- ented. A recessed-gate and a field-plate are used in the device processing to improve the performance of the AIGaN/G... The development of an AIGaN/GaN HEMT power MMIC on SI-SiC designed in microstrip technology is pres- ented. A recessed-gate and a field-plate are used in the device processing to improve the performance of the AIGaN/GaN HEMTs. S-parameter measurements show that the frequency performance of the AIGaN/GaN HEMTs depends significantly on the operating voltage. Higher operating voltage is a key to higher power gain for the AIGaN/GaN HEMTs. The developed 2-stage power MMIC delivers an output power of more than 10W with over 12dB power gain across the band of 9-11GHz at a drain bias of 30V. Peak output power inside the band reaches 14.7W with a power gain of 13.7dB and a PAE of 23%. The MMIC chip size is only 2.0mm × 1. 1mm. This work shows superiority over previously reported X-band AIGaN/GaN HEMT power MMICs in output power per millimeter gate width and output power per unit chip size. 展开更多
关键词 X-BAND AIGAN/GAN HEMTS power MMIC
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Penetrative and migratory behavior of alkali metal in different binder based TiB_2-C composite cathodes 被引量:7
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作者 方钊 伍小雷 +2 位作者 俞娟 李林波 朱军 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第4期1220-1230,共11页
In electrolyte melts containing K at low temperature, the penetrative and migratory path of alkali metals (K and Na) in pitch, furan, phenolic aldehyde and epoxy based TiB2-C composite cathodes during the electrolys... In electrolyte melts containing K at low temperature, the penetrative and migratory path of alkali metals (K and Na) in pitch, furan, phenolic aldehyde and epoxy based TiB2-C composite cathodes during the electrolysis process were studied by EDS and self-made modified Rapoport apparatus. The electrolysis expansion rates, the diffusion coefficients of the alkali metals and the corrosion rates of the composite cathode were also calculated and discussed. The results show that no matter what kind of binder is used, alkali metals have the same penetrative path in composite cathodes:firstly in pore, then in binder and finally in carbonaceous aggregates. K and Na penetrate into both binder and carbonaceous aggregates, which leads to the expansion of composite cathodes, and K has stronger penetration ability than Na. Electrolysis expansion rate of resin based composite cathode is smaller than that of pitch based composite cathodes, and so do the diffusion coefficient and corrosion rate. Resin based composite cathode has better resistance ability to the penetration of alkali metals than pith based composite cathode, and phenolic aldehyde based composite cathode exhibits the strongest resistance ability. The penetration rate, the diffusion coefficient of alkali metals in phenolic aldehyde based TiB2-C composite cathode and the corresponding corrosion rate are 4.72 mm/h, 2.24×10^-5 cm^2/s and 2.31 mm/a, respectively. 展开更多
关键词 aluminum electrolysis PENETRATION migration alkali metal TiB2-C composite cathode corrosion resistance
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