检索结果-南通市图书馆

Magnetic properties and microstructure of nanocrystalline bulk Nd-Fe-B with Ce-Co addition

在线全文

学校读者我要写书评

暂无评论

Journal of Rare Earths 2021年第6期39卷 689-695,I0003页

作者： Yilong Ma Qiqi Yang Xiaoli chen Ying He Wenbo Xiang Jiaqi Lai Bin Shao Donglin Guo dengming chen Kejian Li College of Metallurgy and Materials Engineering Chongqing University of Science and TechnologyChongqing 401331China The Center of Material Analysis and Testing Chongqing University of Science and TechnologyChongqing 401331China

The influence of Ce-Co alloy addition and sintering holding time on permanent magnetic properties and micro structure of nanocrystalline Nd-Fe-B bulk alloy were *** coercivity of Nd-Fe-B bulk alloy can be enhanced greatly by more than 100% after adding Ce-Co ***,when the concentration of Ce-Co is up to 30 wt%,the density of the magnet can reach the maximum value of 7.58 g/cm^(3),but the coercivity does not increase *** the other hand,with the increase of holding time to 10 min,the density and coercivity of magnets increase gradually,reaching up to 7.55 g/cm^(3) and 1134.3 kA/m,*** the addition of Ce-Co alloy,Ce-Co may easily diffuse into the Nd-Fe-B matrix during hot-pressing and under the high pressure and temperature,thus increasing the content of grain boundary phase and the pinning effect of grain boundary,which leads to the increase of *** extension of the hot-pressing holding time may be more conducive to the diffusion of CeCo into the Nd-Fe-B *** addition,the effect of Ce-Co addition on the magnetic properties of Nd-FeB with different content of rare earth was also *** addition of Ce-Co can effectively increase the coercivity of nanocomposite Nd_(2)Fe_(14)B/α-Fe *** addition of Nb to the parent alloy can further improve the *** Nd_(11)Fe_(81.5)Nb_(1)Ga_(0.5)B_(6) alloy with 10 wt% Ce-Co addition,the coercivity can increase from 740.28 to 1098.48 kA/m.

关键词： Nd-Fe-B magnet Ce-Co addition Coercivity Microstructure Nanocomposite Rare earths

大型分析检测设备对研究生实践科研创新能力培养探讨——以重庆科技学院为例

在线全文

学校读者我要写书评

暂无评论

中国现代教育装备 2024年第11期 30-32页

作者：郭东林李春红陈登明曹献龙重庆科技学院冶金与材料工程学院重庆401331

研究生的科研能力及创新能力能否跟上时代发展的步伐成为目前高校研究生教育中面临的紧迫问题,大型仪器设备的使用是研究生实践科研创新能力培养的重要途径。结合重庆科技学院实际情况,分析了大型分析检测设备在研究生培养中存在的不足... 详细信息

研究生的科研能力及创新能力能否跟上时代发展的步伐成为目前高校研究生教育中面临的紧迫问题,大型仪器设备的使用是研究生实践科研创新能力培养的重要途径。结合重庆科技学院实际情况,分析了大型分析检测设备在研究生培养中存在的不足和问题,从多渠道搭建大型分析检测设备共享平台、推动设备开放共享,基于“虚实互补、科教融合”的方式、探索研究生实践教学新模式,多途径建设实验教师队伍,多角度有效提升研究生操作设备能力等方面,对利用大型分析检测设备提高研究生实践科研创新能力进行了探讨。

关键词：大型分析检测设备研究生创新能力科研实践能力

应变诱导Ni原子在纳米晶Fe中的扩散行为研究（英文）

在线全文

学校读者我要写书评

暂无评论

稀有金属材料与工程 2017年第3期46卷 596-600页

作者：孙建春陈登明马毅龙重庆科技学院重庆401331

利用高能喷丸法(HESP)在工业纯铁表面制备了一定厚度无污染、空位、杂质等缺陷的纳米晶层,其平均晶粒尺寸为50 nm,厚度为100μm。在Gleeble 1500热模拟机上,采用脉冲加压扩散(PPD)和恒定加压扩散(CPD)对纳米晶铁在850℃下进行渗镍处理... 详细信息

利用高能喷丸法(HESP)在工业纯铁表面制备了一定厚度无污染、空位、杂质等缺陷的纳米晶层,其平均晶粒尺寸为50 nm,厚度为100μm。在Gleeble 1500热模拟机上,采用脉冲加压扩散(PPD)和恒定加压扩散(CPD)对纳米晶铁在850℃下进行渗镍处理。结果表明,镍原子在纳米晶铁中的扩散系数比常规粗晶中高1个数量级;而采用脉冲加压扩散时,镍原子的扩散系数要比采用恒压扩散高1个数量级。镍原子扩散系数的提高主要包括三方面的原因,一是脉冲加压能击碎扩撒界面上形成的阻碍镍原子扩散的金属件化合物;二是纳米晶铁中形成的大量三叉晶界;三是纳米晶铁中形成大量的非平衡晶界。

关键词：纳米晶铁高能喷丸扩散系数镍原子

在线全文

学校读者我要写书评

暂无评论

Profile of *** chen

Science China(Life Sciences) 2024年第10期67卷 2062-2063页

作者： chen, Songlin Yellow Sea Fisheries Res Inst Qingdao Peoples R China

For decades,*** has been engaged in fish germplasm preservation,sex control and research focusing on molecular breeding for disease *** discovered the first sex-specific molecular marker of fish(chen et al.,2007),deciphered the first fish genome(Chinese tongue sole)in China,revealed the sex determination mechanism in fish(chen et al.,2014),and created molecular sex control *** also discovered the molecular mechanism of metamorphosis in flatfish(Shao et al.,2017)and developed China's first fish disease-resistant breeding gene chip,“YUXIN No.1”.

关键词： technology breeding

Study on the Microstructure and Magnetic Properties of 1J22 Alloy Heat Treated in H2 Atmosphere

在线全文

学校读者我要写书评

暂无评论

Study on the Microstructure and Magnetic Properties of 1J22 ...

Study on the Microstructure of Hot-Pressed and Hot-Deformed Nd-Fe-B Magnets

加速功能材料自主创新，促进西部战略性新兴产业发展——2011中国功能材料科技与产业高层论坛

作者： Yilong MA,dengming chen,Jiandong XUE,Jianchun SUN,Anruo ZHOU College of Metallurgy and Materials Engineering Chongqing University of Science and Technology,Chongqing,China

1J22 alloy of hot rolled bar was heat treated in hydrogen atmosphere at 1150℃,and the magnetic properties and microstructure of alloys before and after heat treatment were studied in *** results showed that after H2 protection heat treatment theαphase content increased and the grain size increased to 200μm;saturation magnetic induction(Bs)and maximum permeability(μm)increased largely while coercivity reduced sharply.

关键词： 1J22 alloy microstructure magnetic properties hydrogen gas heat-treatment

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

Study on the Microstructure of Hot-Pressed and Hot-Deformed ...

制管工艺对1Cr18Ni9Ti航空管晶间腐蚀性能的影响

加速功能材料自主创新，促进西部战略性新兴产业发展——2011中国功能材料科技与产业高层论坛

作者： Yilong MA,Jiandong XUE,dengming chen,Anruo ZHOU,Jianchun SUN College of Metallurgy and Materials Engineering Chongqing University of Science and Technology,Chongqing,China

Anisotropic nano-crystalline Nd-Fe-B magnets were prepared by applying the MQ-C melt-spun powders and the technique of hot-pressing(HP)and hot-deformation(HD).The change of magnetic properties and microstructure was studied in *** results showed that:the HD magnets had a good c-axis texture and the magnetic properties increased largely;the MQ-C powder stacked well along the pressure direction during HP,and the powder particles elongated perpendicular to the pressure direction during HD;in HD magnets,there were a lot of unoriented and coarse grains,which had a higher Nd content than the plate-like grains.

关键词： Nd-Fe-B nano-crystal hot-deformation microstructure

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

热加工工艺 2009年第22期38卷 19-21页

作者：杨军和孙建春陈登明重庆钢铁研究所重庆400084 重庆科技学院冶金与材料工程学院重庆401331

通过对小直径1Cr18Ni9Ti航空管抗晶间腐蚀性与制管工艺关系的分析,指出了提高1Cr18Ni9Ti小直径航空钢管抗腐蚀能力的途径。研究结果表明,除酯不干净的1Cr18Ni9Ti航空管在随后热处理时会出现增C现象,导致其耐蚀性降低;管的直径越小,其抗... 详细信息

通过对小直径1Cr18Ni9Ti航空管抗晶间腐蚀性与制管工艺关系的分析,指出了提高1Cr18Ni9Ti小直径航空钢管抗腐蚀能力的途径。研究结果表明,除酯不干净的1Cr18Ni9Ti航空管在随后热处理时会出现增C现象,导致其耐蚀性降低;管的直径越小,其抗晶间腐蚀性能越差。采用"酸洗除酯→碱洗除酯→低温燃烧除酯"工艺及对小直径管进行稳定化处理可以显著提高1Cr18Ni9Ti航空管的耐蚀性。

关键词：制管工艺 1Cr18Ni9Ti 晶间腐蚀

Effect of Reclamation on the Groundwater-Lake Water Interaction in chen Lake

在线全文

学校读者我要写书评

暂无评论

Journal of Earth Science 2024年第3期35卷 1083-1086页

作者： Kun Lei Teng Ma Liuzhu chen Zhenxing Li Yu chen School of Environmental Studies State Key Laboratory of Biogeology and Environmental GeologyChina University of GeosciencesWuhan 430078China

0 INTRODUCTION To relieve the short supply of suitable land for residing,cultivating,and commerce,it is accepted to reclaim land from lakes,river estuaries,and coastal regions in many countries(Mancini et al.,2020).The large-scale reclamation activities have an irreversible effect on the mico-geomorphology and hydrodynamic system of seasonally flooded areas(Zhang et al.,2019;Yu et al.,2018).For example,coastal regions reclaimed extended the groundwater flow paths,as well as created groundwater level rise,resulting in water-logging in the reclaimed area(Hu et al.,2008).Similar changes in groundwater flow systems may alter groundwater-lake water interactions,and it can ultimately affect the water cycle in the lake ***,such detailed studies are presently *** addition,natural exchanges between the lake and groundwater systems can be strongly affected by physical hydrological processes(Javadzadeh et al.,2020),chemical properties(Kamtchueng et al.,2015),and bioto behavior(Hancock et al.,2005).

关键词： groundwater coastal logging

在线全文

学校读者我要写书评

暂无评论

板坯连铸结晶器内钢液的三维流场数值模拟

热加工工艺 2011年第7期40卷 69-72页

作者：陈登明王宏丹杨治立重庆科技学院冶金与材料工程学院重庆401331

采用数值模拟的方法,建立了描述某厂结晶器内钢液流动的数学模型;用有限体积法求解,研究了结晶器内的钢液流动行为,详细分析了结晶器浸入式水口(SEN)插入深度、侧孔倾角和拉速对结晶器内钢液流场的影响。得出了适合该厂连铸工艺条件的... 详细信息

采用数值模拟的方法,建立了描述某厂结晶器内钢液流动的数学模型;用有限体积法求解,研究了结晶器内的钢液流动行为,详细分析了结晶器浸入式水口(SEN)插入深度、侧孔倾角和拉速对结晶器内钢液流场的影响。得出了适合该厂连铸工艺条件的浸入式水口形式和拉坯速度,即水口合理的出口倾角应为向下15°左右;在水口结构一定条件下,水口插入深度140～170mm比较适宜;合理的拉速应控制在1.4～2.0m/min。

关键词：板坯连铸结晶器流场数值模拟