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酪氨酸酶、过氧化物酶和碱性磷酸酶基因在皱纹盘鲍初生壳形成中的表达分析

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水产学报 2024年第9期48卷 78-86页

作者：殷晓雯谭素建许飞郇聘刘保忠中国科学院海洋研究所实验海洋生物学重点实验室中国科学院大学

为研究软体动物贝壳发育区形成机制，实验通过扫描电子显微镜观察分析了皱纹盘鲍贝壳发育区的形态特征，鉴定了皱纹盘鲍的酪氨酸酶(Hdi-Tyr1和Hdi-Tyr2)、过氧化物酶(Hdi-Prx1、Hdi-Prx2)和碱性磷酸酶(Hdi-Alp)等5个贝壳形成相关的候选... 详细信息

为研究软体动物贝壳发育区形成机制，实验通过扫描电子显微镜观察分析了皱纹盘鲍贝壳发育区的形态特征，鉴定了皱纹盘鲍的酪氨酸酶(Hdi-Tyr1和Hdi-Tyr2)、过氧化物酶(Hdi-Prx1、Hdi-Prx2)和碱性磷酸酶(Hdi-Alp)等5个贝壳形成相关的候选基因，并通过整装原位杂交技术解析了各基因在皱纹盘鲍早期幼虫发育过程中的表达模式。结果显示，皱纹盘鲍贝壳发育区由至少3种特征差异明显的细胞组成，酪氨酸酶基因(Hdi-Tyr1和HdiTyr2)在担轮幼虫的贝壳发育区呈“U”形表达，在面盘幼虫外套膜的长柱状细胞中表达，而碱性磷酸酶(Hdi-Alp)和过氧化物酶(Hdi-Prx1和Hdi-Prx2)基因仅表达在幼虫的担轮环和头部。研究表明，Hdi-Tyr1和Hdi-Tyr2基因可能参与了皱纹盘鲍担轮幼虫和面盘幼虫的贝壳形成过程，而过氧化物酶基因Hdi-Prx1和Hdi-Prx2以及碱性磷酸酶基因Hdi-Alp并不参与初生壳的发育过程，实验结果为深入解析软体动物的贝壳发育机制和贝壳相关性状的种质创新提供了基础支撑。

关键词：皱纹盘鲍贝壳发育区酪氨酸酶过氧化物酶碱性磷酸酶

Progress in recycling of Nd–Fe–B sintered magnet wastes

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Chinese Physics B 2019年第7期28卷 14-24页

作者： Ming Yue xiaowen yin Weiqiang Liu Qingmei Lu College of Materials Science and Engineering Key Laboratory of Advanced Functional Materials(Ministry of Education)Beijing University of Technology

Significant efforts have been put into the recycling of bulk Nd–Fe–B sintered magnet wastes around the world in the past decade because bulk Nd–Fe–B sintered magnet wastes are valuable secondary rare-earth *** are two major facts behind the ***, the waste magnets contain total rare-earth content as high as more than 30 wt.%, which is higher than most natural rare-earth ***, the waste magnets maintain the physical and chemical properties of the original magnets even with deterioration of the properties on surfaces due to corrosion and *** this review,various techniques for recycling bulk Nd–Fe–B sintered magnet wastes, the overall properties of the recycled Nd–Fe–B sintered magnets, and the mass production of recycled magnets from the wastes are reviewed.

关键词： Nd–Fe–B sintered magnet rare-earth resource recycling

Chemical Stability, Ionic Conductivity of BaCe0.9-xZrxSm0.10O3-α and Its Application to Ammonia Synthesis at Atmospheric Pressure

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Chinese Journal of Chemistry 2011年第6期29卷 1114-1118页

作者： Wang, xiaowen yin, Jinling XU, Jianhong Wang, Hongtao Ma, Guilin Key Laboratory of Organic Synthesis of Jiangsu Province College of Chemistry Chemical Engineering and Materials Science Soochow University Suzhou Jiangsu 215123 China

Dense ceramic samples BaCe0.9-xZrxSm0.10O3-α （x=0.10, 0.15, 0.20, 0.30） were obtained by heat-treating the precursors prepared from a coprecipitation route. The phase structure, chemical stability and conduction behaviors of the ceramic samples have been investigated by X-ray powder diffraction and alternating current impedance spectroscopy methods. All the ceramic samples displayed a single phase of orthorhombic perovskite. The samples with x ≥0.20 were relatively stable after exposed to the flowing mixed gases： CO2 （φ=3%）＋H2O （φ=3%）＋N2 （φ= 94%） at 873 K for 12 h. Among the samples tested, the sample with x=0.20 exhibited both adequate conductivity and better chemical stability. The contribution of different charged species for x=0.20 sample to the conduction in wet hydrogen atmosphere was investigated by means of gas concentration cells. It was found that the sample of x= 0.20 was almost a pure ionic conductor, and the ionic conduction was contributed mainly by proton and partially by oxide ion in wet hydrogen atmosphere at 773--1073 K. The ammonia synthesis at atmospheric pressure in an electrolytic cell based on the sample of x=0.20 was successfully conducted and the peak ammonia formation rate achieved 2.67 × 10 ^-9 molos-locm 2 with direct current of 0.80 mA at 773 K.

关键词： BaCe0.9-xZrxSm0.10O3-α chemical stability ion conduction proton transport ammonia synthesis

Recycled Nd-Fe-B sintered magnets prepared from sludges by calcium reduction-diffusion process

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Journal of Rare Earths 2018年第12期36卷 1284-1291页

作者： xiaowen yin Min Liu Baicen Wan Yu Zhang Weiqiang Liu Yufeng Wu Dongtao Zhang Ming Yue College of Materials Science and Engineering Beijing University of Technology Institute of Circular Economy Beijing University of Technology

Environmental friendly recycling process for Nd-Fe-B sintered magnet sludges generated in the manufacturing process, which contain large amount of rare earth, including Nd, Pr and Dy, is badly needed so far. In present study, we have developed an effective route to obtain recycled sintered magnets from Nd-Fe-B sintered magnet sludges by calcium reduction-diffusion(RD) process. Compared to conventional recycling process, our research is focused on recovering most of the useful elements, including Nd, Pr, Dy, Co, and Fe together instead of just rare earth elements. To improve the recycling efficiency and reduce pollution, the co-precipitating parameters were simulated and calculated using MATLAB software. Most of useful elements were recovered by a co-precipitation method, and the obtained composite powders were then directly fabricated as recycled Nd-Fe-B powders by a calcium reduction-diffusion(RD) method. The recovery rates are 98%, 99%, 99%, 93%, and 99%, for Nd, Pr, Dy, Co, and Fe, respectively. The amount of useful elements contained in the recovered composite powders is greater than99.71 wt%. The process of RD for synthesizing NdFeB and subsequently removing CaO was thoroughly investigated. Furthermore, the recycled Nd-Fe-B magnet exhibits a remanence of 1.1 T, a coercivity of1053 kA/m, and an energy product of 235.6 kJ/m~3, respectively, indicating that recycled Nd-Fe-B sintered magnet was successfully recovered from the severely contaminated sludges via an effective recycling route.

关键词： Nd-Fe-B sintered magnet sludges Reduction-diffusion Removing CaO Recycled magnet Rare earths

AlSi10MnMg在汽车车身轻量化中的应用

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汽车实用技术 2024年第1期49卷 167-171页

作者：杨鸿智尹小文苏彦芳王烁于美娟北京汽车研究总院有限公司北京101300 北京新能源汽车股份有限公司北京100176

汽车车身轻量化技术是目前最核心、最关键的轻量化路径方案,包括结构轻量化、材料轻量化和工艺轻量化三大类技术,而AlSi10MnMg铝合金是材料轻量化中的重要应用方向,由于其可以通过不同的热处理得到不同范围的机械性能和极为优异的铸造性... 详细信息

汽车车身轻量化技术是目前最核心、最关键的轻量化路径方案,包括结构轻量化、材料轻量化和工艺轻量化三大类技术,而AlSi10MnMg铝合金是材料轻量化中的重要应用方向,由于其可以通过不同的热处理得到不同范围的机械性能和极为优异的铸造性能,成为了在汽车结构件上使用最为普遍的高强韧压铸合金。文章详细介绍了AlSi10MnMg铝合金材料及其性能,结果表明,该铝合金的T5/T7两种热处理状态,T5态适用于实心件,如安装板;T7态适用于薄壁件,最为典型的应用为前减震器塔、后减震器塔和后纵梁。最后以前减震器塔为例进行了外形、制造工艺和热处理制度方面的设计,可为其他车型前减震器塔的设计开发提供参考。

关键词： AlSi10MnMg 车身轻量化前减震器塔

An Efficient Process for Recycling Nd-Fe-B Sludge as High-Performance Sintered Magnets

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Engineering 2020年第2期6卷 165-172页

作者： xiaowen yin Ming Yue Qingmei Lu Min Liu Feng Wang Yubing Qiu Weiqiang Liu Tieyong Zuo Shanshun Zha Xuliang Li Xiaofei Yi College of Materials Science and Engineering Beijing University of TechnologyBeijing 100124China State Key Laboratory of Rare Earth Permanent Magnetic Materials Hefei 231500China Key Laboratory of Advanced Functional Materials Ministry of EducationBeijing University of TechnologyBeijing 100124China Earth-Panda Advanced Magnetic Materials Co. Ltd.Hefei 231500China

Given the increasing concern regarding the global decline in rare earth reserves and the environmental burden from current wet-process recycling techniques,it is urgent to develop an efficient recycling technique for leftover sludge from the manufacturing process of neodymium-iron-boron(Nd-Fe-B)sintered *** the present study,centerless grinding sludge from the Nd-Fe-B sintered magnet machining process was selected as the starting *** sludge was subjected to a reduction-diffusion(RD)process in order to synthesize recycled neodymium magnet(Nd2Fe14B)powder;during this process,most of the valuable elements,including neodymium(Nd),praseodymium(Pr),gadolinium(Gd),dysprosium(Dy),holmium(Ho),and cobalt(Co),were recovered *** chloride(CaCl2)powder with a lower melting point was introduced into the RD process to reduce recycling cost and improve recycling *** mechanism of the reactions was investigated systematically by adjusting the reaction temperature and calcium/sludge weight *** was found that single-phase Nd2Fe14B particles with good crystallinity were obtained when the calcium weight ratio(calcium/sludge)and reaction temperature were 40 wt% and 1050℃,*** recovered Nd2Fe14B particles were blended with 37.7 wt% Nd4Fe14B powder to fabricate Nd-Fe-B sintered magnets with a remanence of 12.1 kG(1 G=1×10^-4T),and a coercivity of 14.6 kOe(1 Oe=79.6A·m^-1),resulting in an energy product of 34.5 *** recycling route promises a great advantage in recycling efficiency as well as in cost.

关键词： Nd-Fe-B grinding sludge Recycled sintered magnets Calcium reduction-diffusion Rare-earth-rich alloy doping

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一种自适应补偿的宽输入LDO设计

复旦学报（自然科学版） 2018年第1期57卷 85-91页

作者：严利民殷晓文上海大学微电子研究与开发中心上海200072

提出了一种基于CSMC 0.35μm HV40V标准CMOS工艺,输入范围4.5~24V的自适应宽输入的低压差线性稳压器.输出稳定在***系统中输出级加入自适应网络,保证系统在全负载范围内稳定性.此外系统采用超级源随器作缓冲器,引入了简单的负反馈,隔离... 详细信息

提出了一种基于CSMC 0.35μm HV40V标准CMOS工艺,输入范围4.5~24V的自适应宽输入的低压差线性稳压器.输出稳定在***系统中输出级加入自适应网络,保证系统在全负载范围内稳定性.此外系统采用超级源随器作缓冲器,引入了简单的负反馈,隔离了运放输出和功率管栅端,提高了系统稳定性.经Spectre软件仿真验证,当负载电流从1μA变化到20mA时,开环相位裕度为80.81°,交流仿真曲线体现了补偿良好的极点跟随性.

关键词：低压差线性稳压器宽输入自适应网络超级源随器

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战略隔离、能力丧失与代工企业低端锁定

管理评论 2021年第9期33卷 249-259页

作者：胡大立殷霄雯谌飞龙江西财经大学工商管理学院南昌330013 华东交通大学经济管理学院南昌330013

改革开放以来,中国凭借自身的比较优势融入到全球价值链分工中,成为了“世界制造工厂”,并由此实现了经济的快速增长。中国代工企业在与跨国公司合作初期,可以得到跨国公司的协助,顺利实现产品升级和工艺升级。然而,当代工企业试图进入... 详细信息

改革开放以来,中国凭借自身的比较优势融入到全球价值链分工中,成为了“世界制造工厂”,并由此实现了经济的快速增长。中国代工企业在与跨国公司合作初期,可以得到跨国公司的协助,顺利实现产品升级和工艺升级。然而,当代工企业试图进入更高层次的功能升级或者链条升级时,跨国公司会以各种手段进行阻挠,其中一项重要的手段即为战略隔离。本文对跨国公司的战略隔离是如何导致代工企业低端锁定的形成机理进行了理论和实证研究,研究表明,战略隔离与代工企业的低端锁定存在着显著的正相关关系;升级能力丧失与代工企业低端锁定也存在着显著的正相关关系,同时,代工企业技术升级能力丧失和市场升级能力丧失在战略隔离影响代工企业低端锁定形成中充当部分中介作用。在此基础上,本文提出了相应的策略来破解跨国公司的战略隔离,以此突破代工企业的低端锁定,实现代工企业全球价值链高端攀升的目的。

关键词：战略隔离能力丧失低端锁定代工企业策略

NH_3-OH体系中共沉淀法同时回收钕铁硼废料中Nd-Pr-Co-Fe

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稀有金属 2015年第1期39卷 68-74页

作者：赖伟鸿刘敏尹小文索红莉岳明北京工业大学材料科学与工程学院北京100124

为了避免回收单一钕铁硼废料中有价元素带来的操作复杂和资源浪费等问题,本研究采用共沉淀法共沉淀出钕铁硼废料中的有价元素Me（Nd,Pr,Co,Fe）,制备可用于生产再生钕铁硼的原料;根据质量守恒和同时平衡原理,采用MATLAB软件建立Me（Nd,P... 详细信息

为了避免回收单一钕铁硼废料中有价元素带来的操作复杂和资源浪费等问题,本研究采用共沉淀法共沉淀出钕铁硼废料中的有价元素Me（Nd,Pr,Co,Fe）,制备可用于生产再生钕铁硼的原料;根据质量守恒和同时平衡原理,采用MATLAB软件建立Me（Nd,Pr,Co,Fe）-OH--NH3热力学模型,绘制lg[Me]-p H曲线模拟共沉淀工艺,并根据模拟结果确立了共沉淀工艺;模拟和实验的结果表明：根据lg[Me]-p H模拟结果可以确立一步共沉淀法的p H：6～10,Fe^3＋比Fe^2＋更易于沉淀完全;在上述条件下获得的共沉淀粉末主相均为Nd,Pr,Co,Fe的化合物,且有价元素的百分比含量均大于99.4%;其中,当p H值在8左右时回收率最高,在该条件下金属元素Me（Nd,Pr,Co,Fe）的沉淀效率分别为：98.7%,99.9%,93.6%,99.9%。该结果也表明共沉淀法工艺不仅高效,而且所制备的共沉淀粉末可以满足制备二次钕铁硼的需要。

关键词：共沉淀模拟回收率有价元素