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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

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

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

Microstructure and hydrogen storage properties of Mg-based Mg85Zn5Ni10 alloy powders

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Journal of Iron and Steel Research International 2018年第11期25卷 1172-1178页

作者： Yi Yin Bo Li ze-ming yuan Yan Qi yang-huan Zhang Department of Functional Material Research Central Iron and Steel Research InstituteBeijing 100081China Key Laboratory of Integrated Exploitation of Baiyun Obo Multi-Metal Resources Inner Mongolia University of Science and TechnologyBaotou 014010Inner Mongolia China

Mg85Zn5Ni10 ternary alloy was synthesized through vacuum induction melting for the first *** compositions and microstructures of Mg85Zn5Ni10 alloy powders were analyzed by X-ray diffraction (XRD)and scanning electron micro- scopy (SEM).By utilizing a Sieverts apparatus,the hydrogenation and dehydrogenation properties of Mg85Zn5Ni10 powders were measured *** and SEM results indicated that the Mg85Zn5Ni10 alloy powders contained the major phase Mg,the eutectic Mg-Mg2Ni and Mg-MgZn2 *** possible reaction pathway can be inferred as follows:Mg +Mg2Ni +MgZn2 +H2←→MgH2+Mg2NiH4 +MgZn2,indicating that MgZn2 did not react with H2. After activation,the Mg85Zn5Ni10 alloy powders could absorb 5.4 wt.% hydrogen reversibly and held an excellent hydrogenation kinetics at a relatively low *** 360 ℃,the alloy powders desorbed 5.351 wt.% hydrogen in 264 ***,it only had fast dehydrogenation kinetics above 300 ℃.The existence of MgZn2 contributed to improving the kinetic *** the hydriding and dehydriding,the formed cracks and defects promoted the kinetics and thermodynamic *** activation energy for dehydrogenation was 75.514 kJ/*** enthalpy change values of hydrogenation and dehydrogenation were calculated to be -73.064 kJ/mol and 76.674 kJ/mol,respectively,indicating that melting with Ni and Zn could improve the thermodynamic property of Mg slightly.

关键词： Mg85Zn5Ni10 alloy powder Microstructure Hydrogen storage kinetics Activation energy Thermodynamic property

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电力箱涵下穿民房管棚法施工技术

建材技术与应用 2019年第2期 29-32页

作者：袁泽洋许其瑞王正刚袁建芬冯贵情四川华西绿舍预制构件有限公司四川德阳618000 四川华西绿舍建材有限公司四川成都610081

以成都青白江电力隧道建设工程为背景,从施工安全的角度出发,对项目施工的重点和难点进行分析,采取了有效地降水措施和管棚加固处理的方法,制定合理的施工工艺,确保箱涵顶进施工的顺利进行,为类似工程项目提供借鉴。

关键词：电力箱涵管棚施工

Distribution optimization of circulating water in air-cooled heat exchangers for a typical indirect dry cooling system on the basis of entransy dissipation

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Science China(Technological Sciences) 2015年第4期58卷 617-629页

作者： SUN Jian yuan Kai yang Li Jun CHEN Lin DU Xiao ze yang Yong Ping Key Laboratory of Condition Monitoring and Control for Power Plant Equipments of Ministry of Education School of Energy Power and Mechanical Engineering North China Electric Power University

The flow and heat transfer of air-cooled heat exchangers play important roles in the performance of indirect dry cooling systems in power plants,so it is of benefit to the design and operation of a typical indirect dry cooling system to optimize the thermo-flow characteristics of air-cooled heat *** entransy dissipation method is applied to the performance optimization of air-cooled heat exchangers in this *** irreversible heat transfer processes in air-cooled heat exchangers,the heat transfer between circulating water and cooling air and the mixing of circulating water,are taken into account and analyzed by means of the entransy dissipation *** total entransy dissipation rate,which connects the geometrical parameters of air-cooled heat exchanger sectors and the heat capacity rates of the fluids to the heat flow rate in every sector,is *** on the mathematical relation and the conditional extremum method,an optimization equation group is derived,by which the air-cooled heat exchanger with known air-side parameters is optimized,showing that the entransy dissipation based optimization approach can contribute to the distribution optimization of circulating water in air-cooled heat exchangers of a typical indirect dry cooling system.

关键词： indirect dry cooling system air-cooled heat exchanger entransy dissipation optimization

Surface study of the reconstructed anatase TiO2（001） surface

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Progress in Natural Science:Materials International 2021年第1期31卷 1-13页

作者： Guanxing Li Ke Fang yang Ou Wentao yuan Hangsheng yang ze Zhang Yong Wang Center of Electron Microscopy and State Key Laboratory of Silicon Materials School of Materials Science and Engineering Zhejiang University

The anatase TiO2（001） surface has attracted extensive attention in surface science and for practical applications because of its excellent performance. However, the highly reactive（001） surface usually reconstructs to a（1 ×4）-（001） surface, which may potentially alter its properties. As a result, there are still controversial issues concerning the intrinsic performance of this surface. Recently, significant advances have been made in the surface science study of TiO2（001）, which have elucidated its intrinsic physical and chemical properties. In this review,we summarize our present understanding of the structure and properties of the reconstructed TiO2（001） ***, we provide a brief background of the anatase TiO2surfaces, including its low-index surface structures and the synthesis of anatase TiO2nanocrystals with the（001） surface exposed. Next, we focus on the structure,formation mechanism, stability, and surface chemistry of the reconstructed TiO2（001） surface. Finally, we finish this review by highlighting the current challenges of this subject and providing future research perspectives.

关键词： Anatase TiO2 Surface science TiO2 (001) surface Surface reconstruction TiO2 (1×4)-(001) surface

Structure and electrochemical properties of LaMgNi4-xCox(x=0-0.8)hydrogen storage electrode alloys

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Rare Metals 2018年第3期37卷 249-256页

作者： Tai yang Ting-Ting Zhai ze-Ming yuan Wen-Gang Bu Yan Qi yang-Huan Zhang Functional Materials Research Institute Central Iron and SteelResearch Institute Beijing 100081 China Key Laboratory of Integrated Exploitation of Baiyun Obo Multi-Metal Resources Inner Mongolia University of Science andTechnology Baotou 014010 China

LaMgNi（4-x）Cox（x = 0-0.8） electrode alloys used for MH/Ni batteries were prepared by induction melting. The structures and electrochemical hydrogen storage properties of the alloys were investigated in detail.X-ray diffraction（XRD） and scanning electron microscopy（SEM） analysis show that LaMgNi4 phase and LaNi5 phase are obtained. The lattice parameters of the two phases increase first and then decrease with Co content *** electrochemical properties of the alloy electrodes were measured by means of simulated battery tests. Results show that the addition of Co does not change the discharge voltage plateau of the alloy electrodes. However, the maximum discharge capacity increases from 319.9 mAh·g^-1（x = 0）to 347.5 mAh·g^-1（x = 0.4） and then decreases to331.7 mAh·g^-1（x = 0.8）. The effects of Co content on electrochemical kinetics of the alloy electrodes were also performed. The high rate dischargeability（HRD） first increases and then decreases with Co content increasing and reaches the maximum value（95.0 %） when x = 0.4. Test results of the electrochemical impedance spectra（EIS）,potentiodynamic polarization curves and constant potential step measurements of the alloy electrodes all demonstrate that when Co content is 0.4 at%, the alloy exhibits the best comprehensive electrochemical properties.

关键词： Hydrogen storage alloy Element substitution Phase structure Electrochemical performances Kinetics

Maturity Assessment of the Lower Cambrian and Sinian Shales Using Multiple Technical Approaches

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Journal of Earth Science 2021年第5期32卷 1262-1277页

作者： Wei yang Sheng He Gangyi Zhai ze Tao Xiaoqing yuan Sile Wei Key Laboratory of Tectonics and Petroleum Resources Ministry of EducationChina University of GeosciencesWuhan 430074China Oil&Gas Survey China Geological SurveyBeijing 100083China

The Lower Cambrian Niutitang and Sinian Doushantuo shales are the most important and widespread source rocks and target layers in South China. Reliable data of the thermal maturity of organic matter(OM) is widely used to assess hydrocarbon generation and is a key property used in determining the viability and hydrocarbon potential of these new shales. Nevertheless, traditional thermal maturity indicators are no longer suited to the vitrinite-lack marine shales. This study aims to combine high throughput Raman and infrared spectroscopy analysis to confirm and validate the thermal maturity in comparison with the bitumen reflectance(R_(b)). Raman parameters such as the differences between the positions of the two bands(V_(G)–V_(D)) are strong parameters for calculating the thermal maturity in a large vitrinite reflectance(R_(o)) ranging from 1.60% to 3.80%. The infrared spectroscopy analysis indicates that the aromatic C=C bands and CH_(2)/CH_(3) aliphatic groups both are closely correlated with thermal maturity. The calculated R_(o) results from Raman and infrared spectroscopy are in strong coincidence with the R_(b). The relationships between R_(b) and pore volumes/surface areas(calculated from N_(2) adsorption) indicate that the sample with R_(b) of 3.40% has the lowest pore volumes and surface areas. Focused ion beam scanning electron microscopy(FIB-SEM) observations of OM pores indicate that R_(o) of approximately 3.60% may be an upper limit for OM porosity development. Obviously, kerogen Raman and infrared spectroscopy can indicate methods for reducing the risk in assessing maturity with practical, low-cost accurate results. Exploration of shale gas in the high maturity(>3.40%–3.60%) region carries huge risks.

关键词： thermal maturity marine shale kerogen raman spectroscopy infrared spectroscopy