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Defect-rich ultrathin poly-heptazine-imide-framework nanosheets with alkali-ion doping for photocatalytic solar hydrogen and selective benzylamine oxidation

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Nano Research 2022年第10期15卷 8760-8770页

作者： Chaofeng Zhu Xiao Luo Congyan Liu Yang Wang xihai chen Yan Wang Qing Hu Xiaojun Wu Bo Liu School of Chemistry and Materials Science University of Science and Technology of ChinaHefei 230026China Synergetic Innovation of Quantum Information&Quantum Technology CAS Key Laboratory of Materials for Energy Conversionand CAS Center for Excellence in NanoscienceSchool of Chemistry and Materials SciencesUniversity of Science and Technology of ChinaHefei 230026China Max Planck Institute of Colloids and Interfaces Am Mühlenberg 114476 PotsdamGermany

Polymeric carbon nitride(CN)as a metal-free photocatalyst holds great promise to produce high-value chemicals and H_(2) fuel utilizing clean solar ***,the wider deployment of pristine CN is critically hampered by the poor charge carrier transport and high ***,we develop a facile salt template-assisted interfacial polymerization strategy that insitu introduces alkali ions(Na+,K+)and nitrogen defects in CN(denoted as v-CN-KNa)to simultaneously promote charge separation and transportation and steer photoexcited holes and electrons to their oxidation and reduction *** photocatalyst exhibits an impressive photocatalytic H_(2) evolution rate of 8641.5μmol·g^(−1)·h^(−1)(33-fold higher than pristine CN)and also works readily in real seawater(10752.0μmol·g^(−1)·h^(−1))with a high apparent quantum efficiency up to 18.5%at 420 *** addition,we further demonstrate that the v-CN-KNa can simultaneously produce H_(2) and N-benzylidenebenzylamine without using any other sacrificial *** situ characterizations and DFT calculations reveal that the alkali ions notably promote charge transport,while the nitrogen defects generate abundant edge active sites,which further contribute to efficient electron excitation to trigger photoredox reactions.

关键词： carbon nitride photocatalysis alkali ion doping hydrogen production amine oxidative coupling

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Tailoring the texture and mechanical properties of 3%Y_(2)O_(3)p/ZGK200 composites fabricated by unidirectional and cross rolling followed by annealing

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Journal of Magnesium and Alloys 2024年第4期12卷 1479-1495页

作者： xihai Li Hong Yan Zhiwei Shan Rongshi chen Shi-changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of Sciences72 Wenhua RoadShenyang 110016China School of Materials Science and Engineering University of Science and Technology of China72 Wenhua RoadShenyang 110016China School of Materials Science and Engineering Shandong University of Science and TechnologyQingdaoShandong 266590China Center for Advancing Materials Performance from the Nanoscale(CAMP-Nano)and Hysitron Applied Research Center in China(HARCC) State Key Laboratory for Mechanical Behavior of MaterialsXi’an Jiaotong UniversityXi’an 710049China

3%Y_(2)O_(3)p/ZGK200 composites were subjected to unidirectional rolling(UR)and cross rolling(CR)at 400℃and 350℃followed by annealing at 300℃for 1 *** microstructure,texture and mechanical properties of rolled and annealed composites were systematically *** rolled composites exhibited a heterogeneous microstructure,consisting of deformed grains elongated along rolling direction(RD)and Y_(2)O_(3)particles bands distributed along *** annealing,static recrystallization(SRX)occurred and most deformed grains transformed into equiaxed grains.A non-basal texture with two strong T-texture components was obtained after UR while a non-basal elliptical/circle texture with circle multi-peaks was obtained after CR,indicating that rolling path had great influences on texture of the *** annealing process,R-texture component disappeared or weakened,as results,a non-basal texture with double peaks tilting from normal direction(ND)to transverse direction(TD)and a more random non-basal texture with circle multi-peaks were obtained for UR and CR composites,*** yield strength of rolled composites after UR showed obvious anisotropy along RD and TD while a low anisotropic yield strength was obtained after *** Y_(2)O_(3)particles broke during *** fracture of the composites was attributed to the existence of Y_(2)O_(3)clusters and interfacial debonding between particles and matrix during tension,as a result,the ductility was not as superior as matrix alloy.

关键词： Magnesium matrix composites Unidirectional rolling Cross rolling Texture Mechanical properties

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Effect of annealing treatment on the microstructure and mechanical properties of warm-rolled Mg–Zn–Gd–Ca–Mn alloys

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International Journal of Minerals,Metallurgy and Materials 2024年第10期31卷 2208-2220页

作者： Yifan Song xihai Li Jinliang Xu Kai Zhang Yaozong Mao Hong Yan Huiping Li Rongshi chen School of Materials Science and Engineering Shandong University of Science and Technology Shi-changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of Sciences Shandong Key Laboratory of Advanced Aluminium Materials and Technology Binzhou Institute of Technology

The basal texture of traditional magnesium alloy AZ31 is easy to form and exhibits poor plasticity at room temperature. To address these problems, a multi-micro-alloyed high-plasticity Mg–1.8Zn–0.8Gd–0.1Ca–0.2Mn(wt%) alloy was developed using the unique role of rare earth and Ca solute atoms. In addition, the influence of the annealing process on the grain size, second phase, texture,and mechanical properties of the warm-rolled sheet at room temperature was analyzed with the goal of developing high-plasticity magnesium alloy sheets and obtaining optimal thermal-mechanical treatment parameters. The results show that the annealing temperature has a significant effect on the microstructure and properties due to the low alloying content: there are small amounts of larger-sized block and long string phases along the rolling direction(RD), as well as several spherical and rodlike particle phases inside the grains. With increasing annealing temperature, the grain size decreases and then increases, and the morphology, number, and size of the second phase also change correspondingly. The particle phase within the grains vanishes at 450°C, and the grain size increases sharply. In the full recrystallization stage at 300–350°C, the optimum strength–plasticity comprehensive mechanical properties are presented, with yield strengths of182.1 and 176.9 MPa, tensile strengths of 271.1 and 275.8 MPa in the RD and transverse direction(TD), and elongation values of 27.4%and 32.3%, respectively. Moreover, there are still some larger-sized phases in the alloy that influence its mechanical properties, which offers room for improvement.

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重采样和集成学习相结合的文本多标签分类

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计算机科学与探索 2023年第4期17卷 892-901页

作者：王天昊张沛张昭陈西海王晶张柏礼东南大学计算机科学工程学院南京211189 国网山东省电力公司枣庄供电公司山东枣庄277099 智能电网保护和运行控制国家重点实验室南京211106 南瑞集团南京211106

医患纠纷类裁判文书的多标签分类是对其进行高效检索和管理的基础,然而,医患纠纷数据集的类别不平衡和标签共生现象直接影响到文书的多标签分类效果。为此,提出了一种重采样和集成学习相结合的文本多标签分类方案。该方案首先提出一种... 详细信息

医患纠纷类裁判文书的多标签分类是对其进行高效检索和管理的基础,然而,医患纠纷数据集的类别不平衡和标签共生现象直接影响到文书的多标签分类效果。为此,提出了一种重采样和集成学习相结合的文本多标签分类方案。该方案首先提出一种基于标签集合平均稀疏度的样本重采样算法,用于降低标签共生对重采样的影响,从而改善数据集的类别不平衡性;然后,提出一种基于集成学习的多标签分类算法,其基于重采样后的数据集分别训练出多个基分类器,并对各基分类器以一票否决的投票策略进行组合,从而进一步提升分类器的多标签分类效果。实验结果表明,提出的多标签分类方案不仅适用于医患纠纷类裁判文书,而且适用于其他存在类别不平衡和标签共生问题的文本数据集。

关键词：类别不平衡多标签分类集成学习重采样算法标签共生

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无损贮存及涨罐饱和相热力学模型研究

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低温与超导 2011年第7期39卷 13-15,20页

作者：陈喜海苏晨光驻711所军事代表室上海201108 上海船用柴油机研究所上海201203

在低温液体无损贮存及涨罐研究方面,经常采用一种假设容器内气、液相均为饱和相的热力学模型。这种模型比较符合实际,并能够大大简化容器内的热力学状态,是一种比较常用的热力学模型。文中利用一个5m3低温贮罐进行的液氮无损贮存及涨罐... 详细信息

在低温液体无损贮存及涨罐研究方面,经常采用一种假设容器内气、液相均为饱和相的热力学模型。这种模型比较符合实际,并能够大大简化容器内的热力学状态,是一种比较常用的热力学模型。文中利用一个5m3低温贮罐进行的液氮无损贮存及涨罐试验,对该热力学模型进行了对比研究,讨论了饱和相热力学模型误差产生的原因,对于无损贮存和涨罐研究具有指导意义。

关键词：无损贮存涨罐热力学模型

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Tailoring the Texture and Mechanical Anisotropy of Multi-cross Rolled Mg-Zn-Gd Alloy by Annealing

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Acta Metallurgica Sinica(English Letters) 2023年第2期36卷 251-265页

作者： xihai Li Hong Yan Rongshi chen School of Materials Science and Engineering University of Science and Technology of ChinaShenyang110016China Shi-Changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang110016China School of Materials Science and Engineering Shandong University of Science and TechnologyQingdao266590China

The unidirectional rolled Mg-Zn-Gd sheet usually exhibited non-basal texture with two peaks whose tilting angle were about 42°from normal direction to transverse direction(TD),which would cause the mechanical *** this study,multi-cross rolling followed by annealing was used to tailor the texture and mechanical anisotropy for Mg-Zn-Gd *** increasing annealing temperature,the rolled basal texture with two peaks gradually transformed into the circle texture with *** order to figure out different texture components evolution during annealing,the basal texture,R-texture and T-texture component were defined and *** results showed that the change of R-texture and T-texture component was asynchronous with increasing annealing temperature from 250 to 400℃.The tilting angle of R-texture component increased slightly,while the tilting angle of T-texture component increased obviously,and this phenomenon was attributed to the preferential nucleation at grain nucleation stage rather than preferential grain *** yield strength along TD was more sensitive to annealing temperature compared with that along rolling direction(RD),resulting in different descending slopes and yield strength anisotropy with increasing annealing *** at 300℃was the best annealing temperature due to low yield strength anisotropy,moderate strength and good elongation among these annealing *** Schmid factor for basal slip indicated that the activity of basal slip along RD increased slightly,while that along TD increased obviously with increasing annealing temperature from 250 to 400℃,which should be caused by the asynchronous change of R-texture component and T-texture component,consequently resulting in the transformation from isotropic yield strength to anisotropic yield strength.

关键词： Mg-Zn-Gd alloy Annealing Texture Yield strength Electron back-scattering diffraction(EBSD)

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低温容器蒸发率试验及蒸发量波动分析

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低温工程 2010年第2期 42-45,59页

作者：陈喜海汪荣顺上海交通大学制冷与低温工程研究所上海200240

用液氮为试验工质,对3个具有相同结构的35m3高真空多层绝热容器在不同地点进行了日蒸发率试验,对试验中得到的蒸发量与环境温度和环境压强的变化关系进行了分析,认为环境温度的波动虽然是容器内蒸发量波动的内因,但表观蒸发量的波动受... 详细信息

用液氮为试验工质,对3个具有相同结构的35m3高真空多层绝热容器在不同地点进行了日蒸发率试验,对试验中得到的蒸发量与环境温度和环境压强的变化关系进行了分析,认为环境温度的波动虽然是容器内蒸发量波动的内因,但表观蒸发量的波动受大气压变化的影响更大,呈即时的相反关系。同时认为,为了能更真实地反映容器内的实际蒸发率值,应结合气压曲线,对有效测试时段内的总流量取平均值来计算蒸发率,以消除环境波动的影响。

关键词：蒸发率测试蒸发率波动低温压力容器

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去年我国建陶进出口贸易评述

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中国建材 2002年第5期 60-61页

作者：陈西海

据海关初步统计,2001年全国外贸进出口总值为5097.68亿美元,全国建筑卫生陶瓷外贸进出口总值为2.55亿美元,占全国外贸进出口总值的0.05%;全国外贸进出口顺差为225.41亿美元,全国建筑卫生陶瓷外贸进出口顺差达2.14亿美元,占全国外贸进出... 详细信息

据海关初步统计,2001年全国外贸进出口总值为5097.68亿美元,全国建筑卫生陶瓷外贸进出口总值为2.55亿美元,占全国外贸进出口总值的0.05%;全国外贸进出口顺差为225.41亿美元,全国建筑卫生陶瓷外贸进出口顺差达2.14亿美元,占全国外贸进出口顺差的0.95%,比上年翻了一番,创历史最高记录.2001年我国建陶行业出口创汇超2.3亿美元.

关键词：中国建筑陶瓷进出口贸易

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