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Rare Metals 2014年第6期33卷 663-673页

作者： Yang-Huan Zhang Tai Yang Hong-Wei shang chen Zhao Chao Xu 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

In this paper, we comprehensively investigate the influences of M（M=Cu, Co, Mn） substitution for Ni on the structures and electrochemical hydrogen storage characteristics of the nanocrystalline and amorphous Mg20Ni10-xMx（M=Cu, Co, Mn; x = 0–4） alloys prepared by melt spinning. The as-spun（M=None, Cu） alloys display an entire nanocrystalline structure, whereas the as-spun（M=Co, Mn） alloys hold a mixed structure of both nanocrystalline and amorphous when x = 4（M content）. These results indicate that the substitution of M（M=Co, Mn） for Ni facilitates the glass formation in Mg2Ni-type alloy. All the as-spun alloys have the Mg2 Ni major phase, but M（M=Co, Mn） substitution brings on some secondary phases,such as Mg Co2, Mg phases for M=Co, and Mn Ni, Mg phases for M=Mn. The substitution of M（M=Cu, Co, Mn）for Ni also makes a positive contribution to the cycle stability of the alloys in the following orders：（M=Cu） [（M=Co） [（M=Mn） for x = 1 and（M=Co） [（M=Mn）[（M=Cu） for x = 2–4. Meanwhile, it notably enhances the discharge capacity of the alloys in the sequence of（M=Co） [（M=Mn） [（M=Cu）. As for the high rate discharge ability, it visibly upgrades with the growing of M content for（M=Cu, Co）, while it grows at first and then declines for（M=Mn）.

关键词： Mg2Ni-type alloy Element substitution Melt spinning Nanocrystalline and amorphous Electrochemical characteristics

Advances in electrolyte safety and stability of ion batteries under extreme conditions

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Nano Research 2023年第2期16卷 2311-2324页

作者： Zhuo chen Keliang Wang Pucheng Pei Yayu Zuo Manhui Wei Hengwei Wang Pengfei Zhang Nuo shang School of Mechanical Engineering Beijing Institute of TechnologyBeijing 100081China State Key Lab.of Automotive Safety and Energy Tsinghua UniversityBeijing 100084China

Electric vehicles have been promoted worldwide due to fast-charge technology of ion ***,ion batteries’capacity and cycle life severely decay under extreme conditions,which is mostly related to electrolyte conductivity drop and side *** review highlights the safety and stability of ion batteries in terms of thermal stability,non-flammability,low-temperature,and so on,outlining the disadvantages of organic liquid electrolyte,and summarizing effective solutions of polymer electrolytes,solid-state electrolytes,ionic liquid electrolytes,and aqueous electrolytes for the ***,the outlook on the electrolytes is put forward,which is available for research and development of the next generation batteries.

关键词： ion batteries battery safety polymer electrolyte solid state electrolyte ionic liquid electrolyte aqueous electrolyte

First-principles calculations of lattice dynamics and thermal properties of polar solids

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npj Computational Materials 2016年第1期2卷 163-172页

作者： Yi Wang Shun-Li shang Huazhi Fang Zi-Kui Liu Long-Qing chen Department of Materials Science and Engineering The Pennsylvania State UniversityUniversity ParkPennsylvaniaPAUSA

Although the theory of lattice dynamics was established six decades ago,its accurate implementation for polar solids using the direct(or supercell,small displacement,frozen phonon)approach within the framework of density-function-theory-based first-principles calculations had been a challenge until *** arises from the fact that the vibration-induced polarization breaks the lattice periodicity,whereas periodic boundary conditions are required by typical first-principles calculations,leading to an artificial macroscopic electric *** article reviews a mixed-space approach to treating the interactions between lattice vibration and polarization,its applications to accurately predicting the phonon and associated thermal properties,and its implementations in a number of existing phonon codes.

关键词： field lattice solids

Emplacement age and tectonic implications of the brecciated limestone at the edge of the Longmenshan klippe

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Science China Earth Sciences 2016年第3期59卷 590-600页

作者： XUE Zhen Hua shang Qing Hua JIANG Wen Ying WANG Qing chen LI Shuang Jian State Key Laboratory of Lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences Betljing 100029 Institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences Beijing 100044 China University of Chinese Academy of Sciences Beijing 100049 China Institute of Petroleum Exploration and Development China Petroleum and Chemical Corporation Beijing 100083 China

The Longmenshan thrust belt(LMTB) is one of the best natural laboratories for thin-skinned tectonics and has developed a series of NE-SW trending fold-and-thrust structures represented by a series of nappes and klippes, exemplified by the Tangbazi and Bailuding klippe. However, the timing and emplacement mechanism of these klippes are still in dispute. Three possible mechanisms have been proposed:(1) a Mesozoic-Cenozoic southeastward thrusting,(2) a Cenozoic gravity gliding, and(3) glacial deposition. Almost all of these klippes are tectonic and overlaid on folded Late Triassic sandstone except the Tangbazi klippe, which is located in the center of the LMTB and has a narrow tail extending southeastward and covering Jurassic-Quaternary rocks. This geometric relationship is considered the most important stratigraphic evidence to support the post-Cenozoic emplacement of the Longmenshan klippe. Our structural and petrological observations show that the rocks at the front of the Tangbazi and Bailuding structures are brecciated limestone, which is assumed to have been generated by a gravitational collapse and is not characteristic of the massive Permian strata. Artemisia pollen, which has been exclusively recognized in post-Late Eocene strata in Central Asia, was found in the matrix of this brecciated limestone. Therefore, our discovery indicates that the brecciated limestone was deposited after the Late Eocene rather than during the Permian as annotated on the geological map. In contrast, unbrecciated, massive Permian limestone overlaid on the folded Late Triassic rocks. Hence, the anomalous relationship of Permian strata overlaying Late Triassic rocks cannot be evidence of Cenozoic emplacement. According to currently recognized bulk strata relationships, we can only be sure that the klippe was emplaced in the post Late Triassic. The petrological characteristics of the brecciated limestone show that it was crumbled before the re-sedimentation of the breccia, implying tha

关键词： Longmenshan thrust belt Klippe Artemisia Brecciated limestone Thin-skinned structure

Inner Co Synergizing Outer Ru Supported on Carbon Nanotubes for Efficient pH-Universal Hydrogen Evolution Catalysis

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Nano-Micro Letters 2022年第11期14卷 275-289页

作者： Jian chen Yuan Ha Ruirui Wang Yanxia Liu Hongbin Xu Bin shang Renbing Wu Hongge Pan Institute of Science and Technology for New Energy Xi’an Technological UniversityXi’an 710021People’s Republic of China School of Advanced Materials and Nanotechnology Xidian UniversityXi’an 710126People’s Republic of China Department of Materials Science Fudan UniversityShanghai 200433People’s Republic of China State Key Laboratory of New Textile Materials and Advanced Processing Technologies Wuhan Textile UniversityWuhan 430073People’s Republic of China State Key Laboratory of Silicon Materials and School of Materials Science and Engineering Zhejiang UniversityHangzhou 310027People’s Republic of China

Exploring highly active but inexpensive electrocatalysts for the hydrogen evolution reaction(HER)is of critical importance for hydrogen production from electrochemical water ***,we report a multicomponent catalyst with exceptional activity and durability for HER,in which cobalt nanoparticles were in-situ confined inside bamboo-like carbon nanotubes(CNTs)while ultralow ruthenium loading(~2.6μg per electrode area~cm^(−2))is uniformly deposited on their exterior walls(Co@CNTsǀRu).The atomic-scale structural investigations and theoretical calculations indicate that the confined inner Co and loaded outer Ru would induce charge redistribution and a synergistic electron coupling,not only optimizing the adsorption energy of H intermediates(ΔGH*)but also facilitating the electron/mass *** as-developed Co@CNTsǀRu composite catalyst requires overpotentials of only 10,32,and 63 mV to afford a current density of 10 mA cm^(−2) in alkaline,acidic and neutral media,respectively,representing top-level catalytic activity among all reported HER *** current work may open a new insight into the rational design of carbon-supported metal catalysts for practical applications.

关键词： Cobalt nanoparticles Carbon nanotubes Ru nanoclusters Hydrogen evolution reaction

Dynamics of ecosystem carbon stocks during vegetation restoration on the Loess Plateau of China

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Journal of Arid Land 2016年第2期8卷 207-220页

作者： WANG Kaibo DENG Lei REN Zongping SHI Weiyu chen Yiping shang-GUAN Zhouping State Key Laboratory of Loess and Quaternary Geology Institute of Earth EnvironmentChinese Academy of Sciences State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Northwest A&F University State Key Laboratory Base of Eco-Hydraulic Engineering in Arid Area Xi'an University of Technology

In the last few decades, the Loess Plateau had experienced an extensive vegetation restoration to reduce soil erosion and to improve the degraded ecosystems. However, the dynamics of ecosystem carbon stocks with vegetation restoration in this region are poorly understood. This study examined the changes of carbon stocks in mineral soil （0-100 cm）, plant biomass and the ecosystem （plant and soil） following vegetation restoration with different models and ages. Our results indicated that cultivated land returned to native vegetation （natural restoration） or artificial forest increased ecosystem carbon sequestration. Tree plantation sequestered more carbon than natural vegetation succession over decades scale due to the rapid increase in biomass carbon pool. Restoration ages had different effects on the dynamics of biomass and soil carbon stocks. Biomass carbon stocks increased with vegetation restoration age, while the dynamics of soil carbon stocks were affected by sampling depth. Ecosystem carbon stocks consistently increased after tree plantation regardless of the soil depth; but an initial decrease and then increase trend was observed in natural restoration chronosequences with the soil sampling depth of 0-100 cm. Moreover, there was a time lag of about 15-30 years between biomass production and soil carbon sequestration in 0-100 cm, which indicated a long-term effect of vegetation restoration on deeper soil carbon sequestration.

关键词： ages carbon stocks natural vegetation restoration tree plantation Loess Plateau

The stability of deformation twins in aluminum enhanced by alloying elements

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Journal of Materials Science & Technology 2019年第11期35卷 2625-2629页

作者： Linghong Liu Jianghua chen Touwen Fan Shunli shang Qinqin Shao Dingwang Yuan Yu Dai Center for High-Resolution Electron Microscopy College of Materials Science and EngineeringHunan UniversityChangsha410082China College of Science Central South University of Forestry and TechnologyChangsha410004China Department of Materials Science and Engineering The Pennsylvania State UniversityUniversity ParkPA16802USA Advanced Corporation for Materials&Equipment Changsha410111China

Introducing and stabilizing twins in aluminum is a challenge for metals research due to their high formation *** first-principles calculations,we investigated the twin boundary segregation of alloying elements and their impact on the twin boundary energy in *** elements with small solubilities but strong interaction with twin boundary would significantly reduce twin boundary energies in aluminum at low *** increasing temperature,their segregation near twin boundary weakens,leading to their influence on twin boundary energies *** elements with large solubilities may greatly reduce the twin energies not only at low temperatures but also at high *** on careful analysis of charge density and atomic radius,it has been found that chemical difference has little influence on twin boundary energy whereas the atomic size effect plays a leading role in causing the change of twin boundary energy.

关键词： Twins Twin boundary energy Al alloy First-principles calculations

Climatic changes documented by stable isotopes of sedimentary carbonate in Lake Sugan,northeastern Tibetan Plateau of China,since 2 kaBP

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Chinese Science Bulletin 2005年第17期50卷 1930-1939页

作者： QIANG Mingrui chen Fahu ZHANG Jiawu GAO shang-yu ZHOU Aifeng China Center of Desert Research at Beijing Normal University and Key Laboratory of Environmental Changes and Natural Disaster Ministry of Education of China Beijing Normal University Beijing 100875 China Center for Arid Environment and Paleoclimate Research (CAEP) Natiunal Laboratory of Western China's Environmental System Ministry of Education of China Lanzhou University Lanzhou 730000 China

Lake Sugan at the northern edge of the Qaidam Basin was selected as the research object. The temporal se-quence of sedimentary cores retrieved from Lake Sugan since 2 kaBP was reconstructed using the 210Pb, AMS 14C and conventional 14C dating methods. Carbon and oxygen iso-topes of carbonate in the fine-grained lake sediments were analysed. Combined with the changes of δ 18O values of sur-face water and air temperature observation data in the study area, it might be thought that the δ 18O value of the carbon-ate indicates effective moisture, and the changes in δ 13C val-ues are related to annual freeze-up duration of the lake and indirectly indicate air temperature changes in winter half year. From the above, the sequence of climatic changes in the region since 2 kaBP was established. The climatic changes experienced five stages: Warm-dry climate during 0-190 AD; cold-dry climate during 190-580 AD; warm-dry cli-mate during 580-1200 AD (MWP); cold-wet climate during 1200-1880 AD (LIA); cold-dry climate during 1880-1950 AD; and climate warming since 1950s. The air temperature changes in winter half year reflected by carbon isotope since 2 kaBP are in good agreement with the historical literature records and other geologic records, which shows that the climate changes recorded by the stable isotopes from Lake Sugan since 2 kaBP are of universal significance.

关键词：气候变化同位素稳定性碳酸盐沉积作用青藏高原

Metal-organic frameworks as functional materials for implantable flexible biochemical sensors

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Nano Research 2021年第9期14卷 2981-3009页

作者： Ya Li Wei Ling Xinyu Liu Xue shang Pan Zhou Zhaorun chen Hang Xu Xian Huang Department of Biomedical Engineering Tianjin UniversityTianjin 300072China Center of Flexible Wearable Technology Institute of flexible electronic technology ofTsinghuaJiaxing 314006China

Metal-organic frameworks(MOFs)exhibit attractive properties such as highly accessible surface area,large porosity,tunable pore size,and built-in redox-active metal *** may serve as excellent candidates to construct implantable flexible devices for biochemical sensing due to their high thermal and solution ***,MOFs-based sensors have only been mostly reported for in-vitro chemical sensing,their use in implantable chemical sensing and combination with flexible electronics to achieve excellent mechanical compatibility with tissues and organs has rarely been *** paper systematically reviews the biochemical sensors based on MOFs and discusses the feasibility to achieve implantable biochemical sensing through MOFs-based flexible *** properties of MOFs and underlying mechanisms have been intrcxluced,followed by a summarization of different biochemical sensing *** to integrate MOFs with flexible devices have been supplied from the standpoints of matching mechanics and compatible fabrication *** that should be addressed in developing flexible MOFs sensors and potential solutions have also been provided,followed by the perspective for future applications of flexible MOFs *** paper may serve as a reference to offer potential guidelines for the development of flexible MOFs-based biochemical sensors that may benefit future applications in personal healthcare,disease diagnosis and treatment,and fundamental study of various biological processes.

关键词： flexible electronics metal-organic frameworks biosensors chemical sensing implantable devices

Wettability control of defective TiO_(2)with alkyl acid for highly efficient photocatalytic ammonia synthesis

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Nano Research 2023年第8期16卷 10770-10778页

作者： Renquan Guan Xueying cheng Yunning chen Zhengkai Wu Zhao Zhao Qingkun shang Yingnan Sun Zaicheng Sun Faculty of Chemistry Northeast Normal UniversityChangchun 130024China Faculty of Physics Northeast Normal UniversityChangchun 130024China Instrumental Analysis Center Yancheng Teachers UniversityYancheng 224007China Center of excellence for environmental safety and biological effects Beijing Key Lab for Green Catalysis and SeparationFaculty of Environment and lifeBeijing University of TechnologyBeijing 100124China

Ammonia is an important chemical raw material and non-carbon-based *** ammonia production technology as a mild alternative to the traditional Harbor–Bosch route is carried out at the air,liquid,and solid three-phase *** the activation of N_(2),depressing hydrogen evolution reaction(HER),and increasing the local N_(2) concentration around the catalyst surface are critical factors in achieving high conversion *** this paper,we proposed that defective TiO_(2)is surfacemodified by alkyl acids with different carbon chain lengths(C_(2),C_(5),C_(8),C_(11),and C_(14))to tune the catalyst surface *** defect sites greatly promote N_(2) adsorption and *** wettability of the catalyst can be regulated from hydrophilic to hydrophobic by the length of the alkyl *** hydrophobic surface enhances the N_(2) adsorption and increases the local N_(2) concentration due to its ***,it depresses the proton adsorption and ***,the nitrogen reduction reaction(NRR)is greatly *** the series of samples,they present a systematic change and have a maximal NRR performance for n-octanoic acid-defective TiO_(2)(C8-Vo-TiO_(2);Vo=oxygen vacancy).The rate of ammonia production can be as high as 392μmol·g^(−1)·h^(−1).This work provides a new strategy for efficient ammonia synthesis at the three-phase interface using photocatalyst technology.

关键词： aerophilic modification alkyl acids defective TiO_(2) photocatalytic ammonia synthesis