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Journal of Materials Science & Technology 2018年第6期34卷 961-968页

作者： Yu Gao wuzhu sun Weiyi Yang Qi Li Environment Functional Materials Division Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China Institute of Materials China Academy of Engineering Physics Mianyang 621900 China School of Materials Science and Engineering Shandong University of Technology Zibo 255000 China

Palladium nanoparticles were deposited on the amine-grafted glass fiber mat （GFM-NH2） catalyst support by a conventional impregnation process followed by the borohydride reduction in aqueous solution at room temperature to create the designed Pd/GFM-NH2 catalyst. By the use of large size glass fiber mat without nano/mesopores as the catalyst support, the internal mass transfer limitations due to the existence of nano/mesopores on the catalyst support were eliminated and the Pd/GFM-NH2 catalyst could be easily separated from treated water due to the large size of the catalyst support. Batch experiments demonstrate its good catalytic reduction performance of Cr（VI） with formic acid as the reducing agent. It also demonstrated an efficient Cr（VI） removal and stability in a lab-prepared, packed fixed-bed tube reactor for the continuous treatment of Cr（VI）-containing water. Thus, it has a good potential for the catalytic reduction of Cr（VI） in the water treatment practice.

关键词： Palladium nanoparticle Amine-functionalized glass fiber mat Fixed-bed reactor Hexavalent chromium Catalytic reduction

Efficient oxygen reduction reaction by a highly porous,nitrogen-doped carbon sphere electrocatalyst through space confinement effect in nanopores

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Journal of Advanced Ceramics 2021年第4期10卷 714-728页

作者： Zheyang MO Weiyi YANG Shuang GAO Jian Ku SHANG Yajun DING wuzhu sun Qi LI School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Key Laboratory of Advanced Technologies of Materials(Ministry of Education) School of Materials Science and EngineeringSouthwest Jiaotong UniversityChengdu 610031China School of Materials Science and Engineering Shandong University of TechnologyZibo 255000China

A highly porous nitrogen-doped carbon sphere(NPC)electrocatalyst was prepared through the carbonization of biomass carbon spheres mixed with urea and zinc chloride in N_(2) *** sample carbonized at.1000℃ demonstrates a superior oxygen reduction reaction(ORR)performance over the Pt/C electrocatalyst,while its contents of pyridinic nitrogen and graphitic nitrogen are the lowest among samples synthesized at the same or lower carbonization *** unusual result is explained by a space confinement effect from the microporous and mesoporous structures in the microflakes,which induces the further reduction of peroxide ions or other oxygen species produced in the first step reduction to water to have the preferred overall four electron reduction ORR *** work demonstrates that in addition to the amount or species of its aptive sites,the space confinement can be a new approach to enhance the ORR performance of precious-metal-free,nitrogen-doped carbon electrocatalysts.

关键词： precious-metal-free electrocatalyst biomass resource space confinement effect 2e+2e pathway oxygen reduction reaction(ORR)

Electrodeposition in organic system and properties of NiO electrochromic films

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Science China(Technological Sciences) 2012年第6期55卷 1545-1550页

作者： SU Ge SONG MeiQin sun wuzhu CAO LiXin LIU Wei MA DeWen CHEN Na ZHAO LiLi WANG Jing LIU XiaoYun Institute of Material Science and Engineering Ocean University of China Qingdao 266100 China

By electrodeposition in organic system,NiO films with reversible electrochromic property were ***-doped tin oxide glass slices were used as substrates,*** voltammetry and ultraviolet-visible transmission spectroscopy were adopted to study the electrochromic properties of the *** resolution transmission electron microscopy(HRTEM) was employed to analyze the composition and structure of the *** is found that the films are composed of fine NiO crystal grains of a few nanometers in diameter,endowing them with large visible light transmittance variation,rapid switch rate(*** response time) between the bleached and colored *** cycling durability reached 6000 cycles.

关键词： NiO film electrodeposition in organic system electrochromic properties

Divergent responses of runoff to climate change in the upper basins of the Third Pole dominated by westerlies and monsoon

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Science China Earth Sciences 2024年第8期67卷 2592-2614页

作者： Qikai sun Fengge SU He sun State Key Laboratory of Tibetan Plateau Earth System Environment and Resources(TPESER)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100101China

The diverse climates,distribution of snow and glaciers,and geographic locations directly affect the runoff response to climate change in the upper basins of the Third *** present,a comprehensive analysis of runoff variations and their distinct responses to climate change in the westerlies-and monsoon-dominated upper basins is still *** study comprehensively analyzed annual runoff variations in westerlies-dominated basins(the upper basins of the Aksu(UAKS),Syr Darya(USRD),Yarkant(UYK),Hotan(UHT),Amu Darya(UAMD),and Indus(UI))and monsoon-dominated basins(the upper basins of the Yangtze(UYA),Yellow(UYE),Lancang(ULC),Nujiang(UNJ),and Yarlung Zangbo(UYZ))of the Third Pole from 1961 *** multi-source meteorological data and large-scale circulation factors,this study investigated the divergent responses of runoff in the upper basins to climate change,and explored the large-scale circulation mechanisms underlying runoff variations in these upper *** results showed that:(1)The annual runoff in the majority of upper basins(except for the UYE and UYZ)exhibited an increasing trend,and the annual runoff in the UAKS,UYK,and UI showed a significant increasing trend from1961 to *** annual runoff in the upper basins of the Third Pole changed abruptly from decreasing to increasing between the 1980s and 2000s,with the exception of the UYE.(2)The runoff in the monsoon-dominated upper basins has been controlled primarily by changes in precipitation over the past 55 *** contrast,the runoff in the westerlies-dominated upper basins exhibited three distinct long-term responses to climate change:temperature-dominated(UYK and UHT),precipitation-dominated(USRD and UAMD),and the combined influence of precipitation and temperature(UAKS and UI).Since the 1960s,the sensitivity of runoff to warm season temperature changes in the most westerlies-dominated upper basins has decreased,while the response of runoff to precipitation changes has intensified.(3)The stud

关键词： Upper basins of the Third Pole Climate change Westerlies and monsoon Runoff variations Large-scale circulation factors

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New perspectives on deep carbon cycling

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Science China Earth Sciences 2024年第8期67卷 2411-2422页

作者： Weidong sun Center of Deep Sea Research Key Laboratory of Ocean Observation and ForecastingInstitute of OceanologyChinese Academy of SciencesQingdao 266071China Laoshan Laboratory Qingdao 266237China University of Chinese Academy of Sciences Beijing 100049China

The proto-atmosphere serves as a crucial starting point for the carbon *** based on atmospheric data from Mars and Venus suggest that Earth's proto-atmosphere contained>110 bar of CO_(2)and>2.6 bar of *** protoatmosphere had over 1000 bar of water vapor during the magma ocean stage,assuming the proto-ocean had a volume of two oceans of *** this stage both water and carbon dioxide were in a supercritical state at the magma-atmosphere *** serpentinization reactions occurred due to rock-water interaction,producing abundant ***,nitrogen is reduced to ammonia,and carbon dioxide to methane,forming carbonate *** proto-atmosphere dominated by methane,ammonia,and hydrogen formed a significant amount of amino acids through *** process is essential not only to the origin of life,but also to the early carbon-nitrogen cycle on *** the Hadean eon,a large amount of CO_(2)was sequestered as carbonate and organic ***,it mainly entered the deep mantle through mantle overturn or *** the mantle transition zone,carbonate undergoes“Redox freezing”,where carbonate is reduced to diamond through oxidation of ferrous iron in the *** the lower mantle,Fe^(2+)undergoes disproportionation reactions,forming Fe^(3+)and metallic *** these,Fe^(3+)mainly resides in bridgmanite,thereby increasing the oxygen fugacity of the lower mantle,while metallic iron falls to the Earth's *** distribution of carbon in the mantle is crucial for deep carbon *** density curves of diamond and mantle peridotite melt intersect at the bottom of the mantle transition zone(about 660 km).This density crossover leads to the accumulation of diamond during the magma ocean *** materials such as subducting slabs enter the lower mantle,compensatory upwelling of lower mantle material *** enters the upper mantle,decomposes,releasing Fe^(3+)ions and oxidizes diamond

关键词： Carbon cycling Proto-atmosphere Amino acids Subduction initiation Passive margin subduction Atmospheric carbon dioxide

Bi_(25)FeO_(40)/α-Fe_2O_3复合纳米颗粒光催化剂的制备与性能

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高等学校化学学报 2018年第4期39卷 629-635页

作者：丛日敏于怀清罗运军李蛟王卫伟李秋红孙武珠司维蒙张华山东理工大学材料科学与工程学院淄博255049 北京理工大学材料科学与工程学院北京100081

采用溶剂热法,以聚酰胺-胺(PAMAM)树形分子为稳定剂,分别制备了Bi_(25)FeO_(40)和Bi_(25)FeO_(40)/α-Fe_2O_3复合纳米颗粒,并利用X射线衍射仪(XRD)、高分辨透射电镜(HRTEM)、X射线光电子能谱仪(XPS)、紫外-可见吸收光谱仪(UV-Vis)、比... 详细信息

采用溶剂热法,以聚酰胺-胺(PAMAM)树形分子为稳定剂,分别制备了Bi_(25)FeO_(40)和Bi_(25)FeO_(40)/α-Fe_2O_3复合纳米颗粒,并利用X射线衍射仪(XRD)、高分辨透射电镜(HRTEM)、X射线光电子能谱仪(XPS)、紫外-可见吸收光谱仪(UV-Vis)、比表面积和孔径分析仪(BET)和超导量子干涉磁强计等对其结构和性能进行了表征.结果表明,2种颗粒均为球形,尺寸均匀,粒径小于10 nm.当原料中Bi^(3+)/Fe^(3+)摩尔比为25∶1时,产物为Bi_(25)FeO_(40)纳米颗粒;Bi^(3+)/Fe^(3+)摩尔比为1∶1时,产物为Bi_(25)FeO_(40)/α-Fe_2O_3复合纳米颗粒.与Bi_(25)FeO_(40)纳米颗粒相比,Bi_(25)FeO_(40)/α-Fe_2O_3复合纳米颗粒的带隙变窄,对可见光吸收范围变宽,饱和磁化强度和光催化活性明显增强.这是由于复合颗粒中的α-Fe_2O_3具有超顺磁性,且两相界面存在的异质结构有利于光生载流子的分离和迁移,提高催化活性.2种纳米颗粒均可磁性回收,重复使用3次后催化活性下降较小.

关键词： Bi25FeO40 α-Fe2O3 复合纳米颗粒磁性光催化剂

Fossil Equidae in the Linxia Basin with Biostratigraphic and Paleozoogeographic Significance

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Acta Geologica Sinica(English Edition) 2024年第1期98卷 1-9页

作者： sun Boyang Key Laboratory of Vertebrate Evolution and Human Origins of the Chinese Academy of Sciences Institute of Vertebrate Paleontology and PaleoanthropologyChinese Academy of SciencesBeijing 100044China

The Linxia Basin is characterized by an abundance of Cenozoic sediments,that contain exceptionally rich fossil *** are abundant in the Linxia Basin,the fossil record of equids in this region including 16 species that represent 10 *** comparison to other classic late Cenozoic areas in China,the Linxia Basin stands out,because the fauna and chronological data accompanying Linxia equids render them remarkably useful for *** anchitheriines in the region,such as Anchitherium and Sinohippus,represent early equids that appeared in the late stages of the middle and late Miocene,*** the equines,most species of Chinese hipparions have been identified in the Linxia Basin and some species of the genera Hipparion and Hippotherium have FAD records for ***,Equus eisenmannae is one of the earliest known species of Equus in the Old World and is well-represented at the Longdan *** species with precise geohistorical distributions can serve as standards for high-resolution chronological units within this *** at the eastern margin of the Tibetan Plateau and subject to considerable uplift,the Linxia Basin has served as a biogeographic transition area for equids throughout the late Cenozoic.

关键词： Equidae Cenozoic biostratigraphy paleozoogeography Linxia Basin

Achieving simultaneously high conversion and high selectivity for light olefins directly producing from syngas

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Science China Chemistry 2024年第3期67卷 753-754页

作者： Yuhan sun Shanxi Research Institute Huairou Research LaboratoryTaiyuan 030032China Institute of Carbon Neutrality ShanghaiTech UniversityShanghai 201210China

The activity and selectivity are two primary indexes of a successful catalyst for chemical reactions. However,achieving a high activity and a high selectivity simultaneously is a long-standing challenge in catalysis, the socalled activity-selectivity trade-off. In the article recently published in Science, a research team led by Prof.

关键词： selectivity simultaneous catalysis

Fe_3O_4/PAMAM/ZnO/TiO_2核-壳结构纳米颗粒的逐层构建及其光催化性能

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材料研究学报 2018年第10期32卷 759-766页

作者：丛日敏于怀清罗运军李蛟王卫伟李秋红孙武珠司维蒙山东理工大学材料科学与工程学院淄博255049 北京理工大学材料科学与工程学院北京100081

以聚酰胺-胺(PAMAM)树形分子为模板和隔离层采用水热法逐层构建了Fe_3O_4/PAMAM/ZnO/TiO_2和Fe_3O_4/PAMAM/TiO_2核-壳结构纳米颗粒,用HRTEM、EDS、XRD、SQUID和UV-Vis等手段对其结构和性能进行了表征。结果表明,这两种颗粒具有完整清... 详细信息

以聚酰胺-胺(PAMAM)树形分子为模板和隔离层采用水热法逐层构建了Fe_3O_4/PAMAM/ZnO/TiO_2和Fe_3O_4/PAMAM/TiO_2核-壳结构纳米颗粒,用HRTEM、EDS、XRD、SQUID和UV-Vis等手段对其结构和性能进行了表征。结果表明,这两种颗粒具有完整清晰的核-壳结构,磁核与壳层均由尺寸小于5 nm的颗粒聚集而成,具有超顺磁性和较高的MB吸附率。PAMAM隔离层降低了Fe_3O_4核与TiO_2壳接触面积,但是残留在界面处的微量Fe^(2+)电子向壳层迁移,导致壳层能隙变窄、吸收光谱红移以及迁入电子与壳层光生空穴复合,使Fe_3O_4/PAMAM/TiO_2的催化活性降低。Fe_3O_4/PAMAM/ZnO/TiO_2中更厚的PAMAM隔离层和ZnO层阻隔了Fe^(2+)电子向TiO_2层迁移,并且ZnO/TiO_2界面异质结构有利于光生电子-空穴对的分离,界面的新电子态使颗粒吸收光谱进一步红移,提高了对可见光的利用率和催化活性。5次磁性回收循环使用后,Fe_3O_4/PAMAM/ZnO/TiO_2的磁性回收率和MB降解率分别为93.8%和90.8%。

关键词：无机非金属材料 TiO2 ZnO Fe3O4 核-壳结构光催化磁性回收

ONE-PARAMETER FINITE DIFFERENCE METHODS AND THEIR ACCELERATED SCHEMES FOR SPACE-FRACTIONAL SINE-GORDON EQUATIONS WITH DISTRIBUTED DELAY

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Journal of Computational Mathematics 2024年第3期42卷 705-734页

作者： Tao sun Chengjian Zhang Haiwei sun School of Mathematics and Statistics Huazhong University of Science and TechnologyWuhan 430074China Hubei Key Laboratory of Engineering Modeling and Scientific Computing Huazhong University of Science and TechnologyWuhan 430074China Department of Mathematics University of MacaoMacaoChina

This paper deals with numerical methods for solving one-dimensional(1D)and twodimensional(2D)initial-boundary value problems(IBVPs)of space-fractional sine-Gordon equations(SGEs)with distributed *** 1D problems,we construct a kind of oneparameter finite difference(OPFD)*** is shown that,under a suitable condition,the proposed method is convergent with second order accuracy both in time and *** implementation,the preconditioned conjugate gradient(PCG)method with the Strang circulant preconditioner is carried out to improve the computational efficiency of the OPFD *** 2D problems,we develop another kind of OPFD *** such a method,two classes of accelerated schemes are suggested,one is alternative direction implicit(ADI)scheme and the other is ADI-PCG *** particular,we prove that ADI scheme can arrive at second-order accuracy in time and *** some numerical experiments,the computational effectiveness and accuracy of the methods are further ***,for the suggested methods,a numerical comparison in computational efficiency is presented.

关键词： Fractional sine-Gordon equation with distributed delay One-parameter finite difference methods Convergence analysis ADI scheme PCG method