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Construction of 3D porous Cu_(1.81)S/nitrogen-doped carbon frameworks for ultrafast and long-cycle life sodium-ion storage

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 191-200页

作者： Chen Chen Hongyu Xue Qilin Hu Mengfan wang Pan shang Ziyan liu Tao Peng Deyang Zhang Yongsong Luo Key Laboratory of Microelectronics and Energy of Henan Province Henan Joint International Research Laboratory of New Energy Storage TechnologyCollege of Physics and Electronic EngineeringXinyang Normal UniversityXinyang 464000China School of Physics and Electronic Engineering Nanyang Normal UniversityNanyang 473061China

Transition metal sulfides have great potential as anode mterials for sodium-ion batteries(SIBs)due to their high theoretical specific ***,the inferior intrinsic conductivity and large volume variation during sodiation-desodiation processes seriously affect its high-rate and long-cyde performance,unbeneficial for the application as fast-charging and long-cycling SIBs ***,the three-dimensional porous Cu_(1.81)S/nitrogen-doped carbon frameworks(Cu_(1.81)S/NC)are synthesized by the simple and facile sol-gel and annealing processes,which can accommodate the volumetric expansion of Cu_(1.81)S nanoparticles and accelerate the transmission of ions and electrons during Na^(+)insertion/extraction processes,exhibiting the excellent rate capability(250.6 mA·g^(-1)at 20.0 A·g^(-1))and outstanding cycling stability(70% capacity retention for 6000 cycles at 10.0 A·g^(-1))for ***,the Na-ion full cells coupled with Na_(3)V_(2)(PO_(4))_(3)/C cathode also demonstrate the satisfactory reversible specific capacity of 330.5 mAh·g^(-1)at 5.0 A·g^(-1)and long-cycle performance with the 86.9% capacity retention at 2.0 A·g^(-1)after 750 *** work proposes a promising way for the conversionbased metal sulfides for the applications as fast-charging sodium-ion battery anode.

关键词： copper sulfide nanoparticles porous carbon framework fast charging long-cycle performance sodium-ion full batteries

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用改进的透射光栅谱仪定量测量X射线能谱

现代电子技术 2011年第7期34卷 117-119页

作者：岳林霖蒙林况龙钰尚万里巫顺超电子科技大学物理电子学院中国工程物理研究院激光聚变研究中心

利用最新研制的小型化透射光栅谱仪在"神光Ⅲ"原型实验装置上测量了激光注入金腔靶时激光注入口的X射线能谱,首次实现了在上极点附近对柱腔注入口辐射的测量,且实现对X射线的二维空间分辨和谱分辨的测量。改进后的透射光栅谱仪成像系统... 详细信息

利用最新研制的小型化透射光栅谱仪在"神光Ⅲ"原型实验装置上测量了激光注入金腔靶时激光注入口的X射线能谱,首次实现了在上极点附近对柱腔注入口辐射的测量,且实现对X射线的二维空间分辨和谱分辨的测量。改进后的透射光栅谱仪成像系统首次使用一种错位排布的狭缝阵列结构来解决因谱仪尺寸减小带来的能谱分辨问题,并同时达到提高系统空间分辨能力的目的,实现了ICF实验研究中对移动方便和高空间分辨的需求。

关键词：新型透射光栅谱仪狭缝阵列 X射线能谱空间分辨

Large manipulative experiments reveal complex effects of food supplementation on population dynamics of Brandt's voles

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Science China(life Sciences) 2017年第8期60卷 911-920页

作者： Baofa Yin Guoliang li Xinrong wan Guozhen shang wanhong Wei Zhibin Zhang State Key Laboratory of Integrated Management of Pest Insects and Rodents Institute of ZoologyChinese Academy of Sciences College of Bioscience and Biotechnology Yangzhou University

Although food supplementation is well known to increase population density,there is still debate on the causative effects of food supplementation on reproduction,survival,and *** manipulative experiments,which exclude any confounding effects of dispersal and predation,are essential for clarifying the *** this study,we investigated the effects of food supplementation on Brandt's vole population dynamics and plant community in eight large enclosures(0.48 ha each) from2010 to *** supplementation showed significant positive effects on population density due to increases in recruitment;however,it showed a complex effect on survival of voles:positive in non-breeding seasons,but negative in breeding *** addition,food supplementation increased the quality of plants(as reflected by increased crude protein content),but decreased the quantity of less preferred plants in experimental ***,food seems to have direct positive effects on small rodents through improvement of food supply and indirect negative effects through food-induced density-dependent effects,and may have long-term effects on rodents through altering plant community composition and abundance.

关键词： demographic parameters direct and indirect effects food quantity and quality food supplementation plant communitycomposition population dynamics recruitment survival voles

The study of gluon energy loss in cold nuclear matter from J/ψ production

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Chinese Physics C 2018年第12期42卷 106-111页

作者： li-Hua Song lin-wan Yan shang-Fei Xin College of Science North China University of Science and TechnologyTangshan 063210China

The energy loss effects of the incident quark, gluon, and the color octet cc on J/ψ, suppression in p-A collisions are studied by means of the experimental data at E866, RHIC, and LHC energy. We extracted the transport coefficient for gluon energy loss from the E866 experimental data in the middle XF region （0.20 〈 XF 〈 0.65） based on the Salgado-Wiedemann （SW） quenching weights and the recent EPPS16 nuclear parton distribution functions together with nCTEQ15. It was determined that the difference between the values of the transport coefficient for light quark, gluon, and heavy quark in cold nuclear matter is very small. The theoretical results modified by the patton energy loss effects are consistent with the experimental data for E866 and RHIC energy, and the gluon energy loss plays a remarkable role on J/ψ suppression in a broad variable range. Because the corrections of the nuclear patton distribution functions in the J/ψ channel are significant at LHC energy level, the nuclear modification due to the parton energy loss is minimal. It is worth noting that we use the color evaporation model （CEM） at leading order to compute the p-p baseline, and the conclusion in this paper is CEM model dependent.

关键词： J/ψ production energy loss charm quark gluon

Catalysis stability enhancement of Fe/Co dual-atom site via phosphorus coordination for proton exchange membrane fuel cell

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Nano Research 2022年第4期15卷 3082-3089页

作者： Yinuo wang Xin wan Jieyuan liu Wenwen li Yongcheng li Xu Guo Xiaofang liu Jiaxiang shang Jianglan Shui School of Materials Science and Engineering Beihang UniversityBeijing 100081China Qinghai Provincial Key Laboratory of New light Alloys Qinghai Provincial Engineering Research Center of High-Performance Light Metal Alloys and FormingQinghai UniversityXining 810016China

Non-precious metal catalysts(NPMCs)are promising low-cost alternatives of Pt/C for oxygen reduction reaction(ORR),which however suffer from serious stability challenge in the devices of proton-exchange-membrane fuel cells(PEMFC).Different from the traditional strategies of increasing the degree of graphitization of carbon substrates and using less Fenton-reactive metals,we prove here that proper regulation of coordination anions is also an effective way to improve the stability of NPMC.N/P cocoordinated Fe-Co dual-atomic-sites are constructed on ZIF-8 derived carbon support using a molecular precursor of C_(34)H_(28)Cl_(2)CoFeP_(2)and a“precursor-preselected”method.A composition of FeCoN_(5)P1 is infered for the dual-atom active site by microscopy and spectroscopy *** comparing with N-coordinated references,we investigate the effect of P-coodination on the ORR catalysis of Fe-Co dual-atom catalysts in *** metals in FeCoN_(5)P1 have the lower formation energy than those in the solo N-coordinated active sites of FeCoN6 and FeN_(4),and exhibits a much better fuel cell *** anion approach provides a new way to improve the stability of dual-atom catalysts.

关键词： fuel cell oxygen reduction reaction non-precious metal catalyst dual atomic site P/N coordination

Effect of Zn atom in Fe-N-C catalysts for electro-catalytic reactions: theoretical considerations

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Nano Research 2021年第3期14卷 611-619页

作者： Yongcheng li Riming Hu Zhibin Chen Xin wan Jia-Xiang shang Fu-He wang Jianglan Shui School of Materials Science and Engineering Beihang UniversityBeijing100191China Department of Physics Capital Normal UniversityBeijing100048China

Due to the high specific surface area,abundant nitrogen and micropores,ZIF-8 is a commonly used precursor for preparing high performance Fe-N-C ***,the Zn element is inevitably remained in the prepared Fe-N-C *** the residual Zn element affects the catalytic activity and active site center of the Fe-N-C catalyst caused widespread curiosity,but has not been studied ***,we built several Fe,Zn,and N co-doped graphene models to investigate the effect of Zn atoms on the electrocatalytic performance of Fe-N-C catalysts by using density functional theory *** calculation results show that all the calculated Fe-Zn-N_(x) structures are thermodynamically stable due to the negative formation energies and relative *** active sites around Fe and Zn atoms in the structure of Fe-Zn-N_(6)(III)show the lowest oxygen reduction reaction(ORR)and oxygen evolution reaction(OER)overpotentials of 0.38 and 0.43 V,*** bridge site of Fe-Zn in Fe-Zn-N_(5) shows the lowest η^(HER) of−0.26 V.A few structures with a better activity than that of FeN_(4) or ZnN_(4) are attributed to the synergistic effects between Fe and Zn *** calculated ORR reaction pathways on Fe-Zn-N6(III)show that H_(2)O is the final product and the ORR mechanism on the catalyst would be a four-electron process,and the existence of Zn element in the Fe-N-C catalysts plays a key role in reducing the ORR activation energy *** results are helpful for the deep understand of high-performance Fe-N-C catalysts.

关键词： Fe-N-C Zn-N-C oxygen reduction reaction oxygen evolution reaction hydrogen evolution reaction density functional theory

Quasi-static and low-velocity impact mechanical behaviors of entangled porous metallic wire material under different temperatures

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Defence Technology（防务技术） 2023年第1期19卷 143-152页

作者： Yi-wan Wu Hu Cheng shang-zhou li Yu Tang Hong-bai Bai Chun-hong Lu Engineering Research Center for Metal Rubber School of Mechanical Engineering and AutomationFuzhou UniversityFuzhou350116China Department of Automotive Engineering Hebei College of Industry and TechnologyShijiazhuang050091China

To improve the defense capability of military equipment under extreme conditions,impact-resistant and high-energy-consuming materials have to be *** damping characteristic of entangled porous metallic wire materials(EPMWM)for vibration isolation was previously *** this paper,a study focusing on the impact-resistance of EPMWM with the consideration of ambient temperature is *** quasi-static and low-velocity impact mechanical behavior of EPMWM under different temperatures(25℃-300℃)are systematically *** results of the static compression test show that the damping energy dissipation of EPMWM increases with temperature while the nonlinear damping characteristics are gradually *** the impact experiments,the impact energy loss rate of EPMWM was between 65%and 85%,while the temperatures increased from 25℃to 300℃.Moreover,under the same drop impact conditions,the overall deformation of EPMWM decreases in the temperature range of 100℃-200℃.On the other hand,the impact stiffness,energy dissipation,and impact loss factor of EPMWM significantly increase with *** can be attributed to an increase in temperature,which changes the thermal expansion coefficient and contact state of the internal wire ***,the energy dissipation mode(dry friction,air damping,and plastic deformation)of EPMWM is also ***,the EPMWM may act as a potential candidate material for superior energy absorption applications.

关键词： Entangled porous metallic wire material Low-velocity impact High temperature Energy dissipation characteristics Mechanical behavior

Improving landscape connectivity through habitat restoration:application for Asian elephant conservation in Xishuangbanna Prefecture,China

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Integrative Zoology 2024年第2期19卷 319-335页

作者： Bin wan Wenwen li Peng liU Nian YANG shang CHEN Xianming GUO Bin wanG li ZHANG Key Laboratory for Biodiversity Science and Ecological Engineering Ministry of EducationCollege of Life SciencesBeijing Normal UniversityBeijingChina Research Center for Coastal Zone Science and Marine Development Strategy First Institute of OceanographyMinistry of Natural ResourcesQingdaoChina School of Biological Sciences The University of Hong KongPokfulamHong KongChina Research Institute of Xishuangbanna National Nature Reserve JinghongChina Xishuangbanna Asian Elephant Conservation and Management Center JinghongChina

Habitat restoration is an effective method for improving landscape connectivity,which can reduce habitat *** landscape connectivity could promote connections between habitat,which is extremely essential to preserve gene flow and population *** study proposes a methodological framework to analyze landscape connectivity for Asian elephant habitat conservation,aiming to provide practical options for reducing habitat fragmentation and improving habitat *** approach involved combining a species distribution model using MaxEnt and landscape functional connectivity models using graph theory to assess the impact on connectivity improvement via farmland/plantation restoration as *** results showed that:(1)there were 119 suitable habitat patches of Asian elephant covering a total area of 1952.41 km^(2).(2)The connectivity between habitats improved significantly after vegetation restoration and the gain first decreased and then increased with the increase of dispersal distance.(3)The first few new habitat patches that were identified played an important role in improving connectivity,and the variation rate of connectivity gradually leveled off as the number of new habitats increased.(4)Prioritization of the 25 best new habitat patches increased connectivity from 0.54%to 5.59%as the dispersal distance increased and mainly was located between two Asian elephant distribution regions and two *** of new habitat patches was effective for improving or restoring *** findings can be used as guidance for improving the studied fragmented Asian elephant habitats,and they can also be used as a reference for the habitat restoration of other endangered species heavily affected by habitat fragmentation.

关键词： Asian elephant connectivity habitat restoration habitat suitability landscape graphs

Ideal tensile strength of chromium by first-principles method

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Rare Metals 2023年第6期42卷 2087-2092页

作者： Feng li Jia-Xiang shang School of Materials Science and Engineering Beihang UniversityBeijing100191China

The ideal tensile strengths of Cr along [001],[110] and [111] directions were calculated based on the first-principles *** results show that the ideal tensile strengths are 30.83,37.2 and 35.49 GPa for antiferromagnetic Cr,while they are 33.09,47.15 and38.11 GPa for non-magnetic Cr along [001],[110] and[111] directions,*** is obvious that [001] is the weakest *** the loading is applied on the direction [001],the ideal tensile strength is reached before the shear instability for both the anti-ferromagnetic and non-magnetic Cr;thus,Cr fails by cleavage and it is deemed to be intrinsically ***,for the antiferromagnetic Cr,the correlation between the magnetic moment and volume was analyzed,and the result shows that the magnetic moment increases with the increase in volume and eventually disappears with the increase in *** addition,the density of states in the process of loading was also discussed.

关键词： First-principles Chromium Theoretical tensile strength Electron theory