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Acta Metallurgica Sinica(English Letters) 2019年第8期32卷 961-971页

作者： Zhen-yang Li Sheng-Li Li ze-Ming yuan yang-Huan Zhang School of Materials Science and Engineering Shandong UniversityJinan 250061China Key Laboratory of Integrated Exploitation of Baiyun Obo Multi-Metal Resources Inner Mongolia University of Science and TechnologyBaotou 014010China Department of Functional Material Research Central Iron and Steel Research InstituteBeijing 100081China

The eifects of Ni content and ball milling time on the hydrogen storage thermodynamics and kinetics performances of asmilled La5Mg95-xNix(x=5,10,15)ternary alloys have been *** evolution of microstructure and phase of experimental alloys in the absorption/desorption process has been characterized by XRD,SEM and *** hydrogen storage kinetics and thermodynamics performances and PCI curves have been tested using the Sievert *** is found that the rising of Ni content remarkably improves the hydrogen storage kinetic performance,but reduces hydrogen storage *** with the increase in milling time,hydrogen desorption activation(Ea)value decreases firstly and then increases;the minimum value is 47.6 kJ/mol,and the corresponding milling time is 10 h for La5Mg85Ni10 *** for the thermodynamics properties,the hydrogenation enthalpy(△H)and hydrogenation entropy(△S)both decrease firstly and then increase with the rising of Ni content and milling *** composite La5Mg85Ni10 alloy milled for 10 h exhibits the best thermodynamics and kinetics performances,the lowest Ea of 47.6 kJ/mol,absorption of 5.4 wt.%within 5 min and desorption of 5.2 wt.%within 3 min at 360℃and the lowest△H and△S of 72.1 kJ/mol and 123.2 J/mol/K.

关键词： Hydrogen storage Mg-based alloys Thermodynamics and kinetics Ni content Milling time

g-C_(3)N_(4)/Pd/Bi_(2)WO_(6)光催化剂协同降解苯扎贝特机理研究

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中国环境科学 2024年第5期44卷 2504-2513页

作者：尹泽高博熠刘愿强高爱舫河北地质大学水资源与环境学院河北石家庄050031 河北省水资源可持续利用与开发实验室河北省高校生态环境地质应用技术研发中心河北省水资源可持续利用与产业结构优化协同创新中心河北石家庄050031

利用贵金属Pd的等离子体共振效应和形貌可控Bi2WO6的光催化协同作用,通过低温水热法设计合成具有高效可见光活性的花状g-C_(3)N_(4)/Pd/Bi_(2)WO_(6)异质结复合催化剂.在可见光照射下,异质结复合催化剂光催化降解BZF的去除率均高于g-C_(... 详细信息

利用贵金属Pd的等离子体共振效应和形貌可控Bi2WO6的光催化协同作用,通过低温水热法设计合成具有高效可见光活性的花状g-C_(3)N_(4)/Pd/Bi_(2)WO_(6)异质结复合催化剂.在可见光照射下,异质结复合催化剂光催化降解BZF的去除率均高于g-C_(3)N_(4),g-C_(3)N_(4)/Bi_(2)WO_(6),Pd/g-C_(3)N_(4)和Bi_(2)WO_(6),其中,50%g-C_(3)N_(4)/Pd/Bi_(2)WO_(6)对BZF的去除率为96%,是Pd/g-C_(3)N_(4)的1.8倍,g-C_(3)N_(4)和Bi_(2)WO_(6)的2.7倍.基于表征分析可知,g-C_(3)N_(4)/Pd/Bi_(2)WO_(6)复合催化剂中Bi_(2)WO_(6)呈现中心辐射花状纳米结构,并与层状Pd/g-C_(3)N_(4)连接;贵金属Pd可作为电子传输的介质,促进g-C_(3)N_(4)和Bi_(2)WO_(6)Z型异质结构的形成,有利于协同提升可见光催化活性.淬灭实验和EPR表征证实了·OH是g-C_(3)N_(4)/Pd/Bi_(2)WO_(6)催化降解BZF的主要活性物质,LC-MS/MS分结果表明羟基化作用取代贝特链是BZF降解的主要路径.

关键词：苯扎贝特 Pd g-C_(3)N_(4) Bi_(2)WO_(6) 异质结

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蒸养混凝土中矿物掺合料的激发效应研究

建材技术与应用 2014年第6期 1-4页

作者：袁泽洋何顺爱伍勇华四川华西绿舍建材有限公司四川成都610081 西安建筑科技大学材料与矿资学院陕西西安710055

研究了在蒸汽养护条件下,复合激发剂对常用的3种矿物掺合料矿粉、钢渣粉、粉煤灰的激发效应。结果表明:以抗压强度为指标,三者均存在最佳掺量,复合激发剂对矿粉的激发效应最好,其最佳掺量为50%,激发剂的最佳掺量为矿粉掺量的6%;复合激... 详细信息

研究了在蒸汽养护条件下,复合激发剂对常用的3种矿物掺合料矿粉、钢渣粉、粉煤灰的激发效应。结果表明:以抗压强度为指标,三者均存在最佳掺量,复合激发剂对矿粉的激发效应最好,其最佳掺量为50%,激发剂的最佳掺量为矿粉掺量的6%;复合激发剂对粉煤灰的激发效应次之,对钢渣的激发效应最差。在其他条件相同的情况下,与标准养护相比,蒸汽养护更有利于复合激发剂对矿粉的激发效应。

关键词：蒸汽养护复合激发剂矿物掺合料强度

基于流量特征重构与映射的物联网DDoS攻击单流检测方法

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电信科学 2024年第1期40卷 92-105页

作者：谢丽霞袁冰迪杨宏宇胡泽成翔张良中国民航大学计算机科学与技术学院天津300300 中国民航大学安全科学与工程学院天津300300 扬州大学信息工程学院江苏扬州225127 亚利桑那大学信息学院美国亚利桑那图森AZ 85721

针对现有检测方法对物联网(IoT)分布式拒绝服务(DDoS)攻击响应速度慢、特征差异性低、检测性能差等不足,提出了一种基于流量特征重构与映射的单流检测方法(SFDTFRM)。首先,为扩充特征,使用队列按照先入先出存储定长时间跨度内接收的流量... 详细信息

针对现有检测方法对物联网(IoT)分布式拒绝服务(DDoS)攻击响应速度慢、特征差异性低、检测性能差等不足,提出了一种基于流量特征重构与映射的单流检测方法(SFDTFRM)。首先,为扩充特征,使用队列按照先入先出存储定长时间跨度内接收的流量,得到队列特征矩阵。其次,针对物联网设备正常通信流量与DDoS攻击流量存在相似性的问题,提出一种与基线模型相比更加轻量化的多维重构神经网络模型与一种函数映射方法,改进模型损失函数按照相应索引重构队列定量特征矩阵,并通过函数映射方法转化为映射特征矩阵,增强包括物联网设备正常通信流量与DDoS攻击流量在内的不同类型流量之间的差异和同类型流量的相似性。最后,使用文本卷积网络、信息熵计算分别提取映射特征矩阵和队列定性特征矩阵的频率信息,得到拼接向量,丰富单条流量的特征信息并使用机器学习分类器进行DDoS攻击流量检测。在两个基准数据集上的实验结果表明,SFDTFRM能够有效检测不同类型的DDoS攻击,检测性能指标平均值与现有方法相比最多提升12.01%。

关键词： DDoS攻击检测多维重构函数映射机器学习

Hydrogen storage properties of La1-xPrxMgNi3.6Co0.4（x=0-0.4） alloys with annealing treatment

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Rare Metals 2019年第9期38卷 871-876页

作者： Ting-Ting Zhai Sheng Xu Tai yang ze-Ming yuan yang-Huan Zhang Department of Functional Material Research Central Iron and Steel Research InstituteBeijing 100081China College of Science Northeastern UniversityShenyang 110819China

The as-cast RE-Mg-Ni-b ased AB2-type La1-xPrxMgNi3.6Co0.4(x=0-0.4)alloys were prepared by vacuum induction melting followed by annealing *** phase composition and structure were characterized by X-ray diffraction(XRD)and scanning electron microscope(SEM).The results show that LaMgNi4 and LaNi5 coexist in as-cast alloys,but only LaMgNi4 is detected in the annealed *** morphology of annealed alloys is more homogeneous than that of as-cast *** gaseous hydrogen storage and electrochemical properties were investigated by pressure-composition isotherm(P-C-T)and electrochemical *** P-C-T curves of annealed alloys show flatter and wider pressure plateaus corresponding to absorption/desorption pressure plateaus of LaMgNi4 *** the maximum hydrogen storage content of annealed alloys is lower than that of as-cast *** consideration of the electrochemical properties,the annealed La0.8Pr0.2MgNi3.6Co0.4alloy exhibits a maximum discharge capacity of354.2 mAh·g-1.

关键词： LaMgNi4 P-C-T Annealing treatment Hydrogen storage properties

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新疆风力发电减碳效益全生命周期评估

生态学报 2024年第8期44卷 3293-3302页

作者：杜文杰关梦茜江源曹鹏鹤王泽康慕谊北京师范大学地理科学学部地表过程与资源生态国家重点实验室北京100875

风力发电减碳效益评估有助于从减碳角度更好制定能源发展相关政策。以风力资源总体丰富且亟需发展风力发电以实现能源系统脱碳的新疆为研究区,将生命周期方法与风力发电模型结合,在省、市级尺度分别评估了风力发电全生命周期的排放水平... 详细信息

风力发电减碳效益评估有助于从减碳角度更好制定能源发展相关政策。以风力资源总体丰富且亟需发展风力发电以实现能源系统脱碳的新疆为研究区,将生命周期方法与风力发电模型结合,在省、市级尺度分别评估了风力发电全生命周期的排放水平及发电效益,核算了风力发电相对于火力发电和光伏发电的减碳效益,有效弥补了传统生命周期评估中空间差异考虑不充分的问题。结果表明,风机全生命周期平均发电量为13.1×10^(7)kWh,风力发电全生命周期共排放3944.24 tCO_(2)⁃eq,通过材料处置回收和循环再利用可减少1424.79 tCO_(2)⁃eq。新疆发展风力发电具有低排放强度和高减碳效益的特点,与火电相比可减少97.44%排放,减碳效益平均可达906.72 gCO_(2)⁃eq/kWh,并且应优先布局在哈密、巴音郭楞蒙古自治州和北屯市;与光伏相比,减碳效益可分别达到43.85 gCO_(2)⁃eq/kWh(衰减率DR=1%)和169.84 gCO_(2)⁃eq/kWh(DR=3%),此情景下风电应主要部署在克孜勒苏柯尔克孜自治州、喀什和和田。在风电减碳效益较差地区如石河子市、铁门关市和双河市应考虑利用本地充足太阳能资源发展光伏发电。需注意风电的排放强度和减碳效益在局地小尺度评估中存在不确定性,获取更精细的结果仍需进一步评估。未来应大力发展新疆本地的风电产业,打造绿色供应链和加快发展处置回收技术以增加减碳效益。

关键词：风力发电生命周期评价碳排放发电量新疆

维普期刊数据库博看期刊

退火温度对TiNi记忆合金马氏体相变超弹性能的影响

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材料热处理学报 2024年第8期45卷 85-91页

作者：王涛涛武泽园李亚鹏陕西理工大学材料科学与工程学院陕西汉中723001

采用X射线衍射仪、差示扫描量热法、透射电镜和拉伸试验等研究了退火温度对拉拔变形后的TiNi记忆合金的微观组织、马氏体相变应力、回复应变、残余应变、吸收能量、储存能量及耗散能量的影响。结果表明:当退火温度由350℃升高至550℃,T... 详细信息

采用X射线衍射仪、差示扫描量热法、透射电镜和拉伸试验等研究了退火温度对拉拔变形后的TiNi记忆合金的微观组织、马氏体相变应力、回复应变、残余应变、吸收能量、储存能量及耗散能量的影响。结果表明:当退火温度由350℃升高至550℃,TiNi记忆合金的平均晶粒尺寸由15 nm增大至400 nm,马氏体相变应力由766 MPa降低至115 MPa,回复应变由6.7%减小至0.8%,残余应变由1.3%增大至7.2%,马氏体相变的吸收能量由50.6 MJ/m^(3)减小至8.6 MJ/m^(3),马氏体相变的储存能量由15.7 MJ/m^(3)减小至0.8 MJ/m^(3),马氏体相变的耗散能量由34.9 MJ/m^(3)减小至8.0 MJ/m^(3)。分析认为退火温度对上述TiNi记忆合金马氏体相变超弹性能的影响主要是因为随着退火温度的升高,TiNi记忆合金的晶粒尺寸增大,晶界密度降低,由此降低了合金应力诱发马氏体相变的阻力,进而影响其超弹性能。

关键词： TiNi记忆合金马氏体相变退火温度超弹性

Supramolecular Polymerization Driven by the Dimerization of Single-stranded Helix to Double-stranded Helix

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Chinese Journal of Polymer Science 2018年第3期36卷 261-261,262-265页

作者： Chao zeng Chen-yang Zhang Jun-Yan Zhu ze-yuan Dong State Key Laboratory of Supramolecular Structure and Materials College of ChemistryJilin UniversityChangchun 130012China

We reported a type of strong and highly directional non-covalent interactions based on the dimerization of single-stranded helix to double-stranded helix that can achieve supramolecular polymerization, giving rise to ... 详细信息

关键词： Helix Double-stranded helix Supramolecular polymers Supramolecular polymerization Dimerization

Calculation of the energy dependence of fission fragments yields and kinetic energy distributions for neutron-induced ^(235)U fission

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Chinese Physics C 2024年第8期48卷 159-169页

作者： Ya-Ning Han Zheng Wei Yi-Xuan Wang Dong-Ying Huo Peng-Qi Zhang Ming Li Jun Ma Kang Wu Yong-Guang Zheng yuan He Zhi-Yong Deng Tian-Zhi Jiang Xiang-Lin Zhuo Jin Li Yun Zhang Yu Zhang Jun-Run Wang Xiao-Dong Su ze-En Yao School of Nuclear Science and Technology Lanzhou UniversityLanzhou 730000China Engineering Research Center for Neutron Application Technology Ministry of EducationLanzhou UniversityLanzhou 730000China MOE Frontiers Science Center for Rare Isotopes Lanzhou UniversityLanzhou 730000China School of Mathematics and Statistics Lanzhou UniversityLanzhou 730000China Nuclear Power Institute of China Chengdu 610000China

Fission fragments yields and average total kinetic energy are fundamental nuclear data for nuclear energy applications and the study of nuclear *** fission products,such as ^(95)Zr,^(99)Mo,^(140)Ba,^(144)Ce,and ^(147)Nd,serve as burnup monitors,assessing the number of fissions induced by neutrons on ^(235)***,current experimental data for these fission products worldwide are inconsistent,introducing significant uncertainty into related scientific *** this study,we employed the Potential-driving Model to calculate the independent yields of ^(235)U and evaluate its advantages in such ***,we investigated the energy dependence of independent yields to select important ***,we calculated the cumulative yields of ^(95)Zr,^(99)Mo,^(140)Ba,^(144)Ce,and ^(147)Nd,and compared them with existing literature data to explore the energy dependence of fission products for ^(235)*** the lack of fission product yield data above 14.8 MeV,we extended our calculated incident neutron energy to 20 MeV,aiming to support future scientific *** Geant4 physical model does not consider the influence of incident neutron energy on the average total kinetic energy of fission fragments;thus,we introduced the excitation function of the total kinetic energy of fission fragments recommended by Madland et al.,which effectively describes the experimental data of the average total kinetic energy of fragments formed in ^(235)U *** this paper,we comprehensively discuss the energy dependence of fission product yields and average total kinetic energy.

关键词： ^(235)U(n f) potential-driving model fission yields kinetic energies energy dependence

Properties of Mechanically Milled Nanocrystalline and Amorphous Mg–Y–Ni Electrode Alloys for Ni–MH Batteries

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Acta Metallurgica Sinica(English Letters) 2015年第7期28卷 826-836页

作者： yang-Huan Zhang ze-Ming yuan Tai yang Zhong-Hui Hou Dong-Liang Zhao Key Laboratory of Integrated Exploitation of Baiyun Obo Multi-Metal Resources Inner Mongolia University of Science and Technology Department of Functional Material Research Central Iron and Steel Research Institute

Nanocrystalline and amorphous Mg2Ni-type Mg20-xYxNi10（x = 0,1,2,3 and 4） electrode alloys were fabricated using mechanical *** effects of the Y content and milling time on the microstructures and electrochemical performances of the alloys were investigated in detail.X-ray diffraction and transmission electron microscopy analyses revealed that the substitution of Y for Mg yields an obvious change in the phase composition and micro morphology of the *** the Y content x ≤ 1,the substitution of Y for Mg does not change the major phase Mg2 Ni,but with a further increase in the Y content,the major phase of the alloys transforms into the YMg Ni4 YMg3 phase.A nanocrystalline and amorphous structure can be obtained by mechanical milling,and the amorphisation degree of the alloy visibly increases with increased milling *** measurements indicate that the discharge capacity of the alloys first increases and then decreases with increasing Y content and milling *** substitution of Y for Mg dramatically ameliorates the cycle stability of the as-milled alloys,and the mechanical milling more or less impairs the cycle stability of the ***,the high rate discharge ability,electrochemical impedance spectrum,Tafel polarisation curves and potential step measurements indicate that the electrochemical kinetic properties of the as-milled alloys first increase and then decrease with increasing Y content and milling time.

关键词： Mg2Ni-type alloy Y substitution for Mg Milling time Electrochemical performance