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Journal of Materials Science & Technology 2023年第23期154卷 129-139页

作者： mingyi yu Jianbo Wang Guojun Li Shule Zhang Qin Zhong School of Chemistry and Chemical Engineering Nanjing University of Science and TechnologyNanjing 210094China

Indium vanadate (InVO4 ) possesses excellent potential in photocatalytic carbon dioxide (CO_(2) ) reduction, but further modifications of reducing charge recombination and increasing active sites are still needed. Herein, InVO4 /g-C3 N4 (InVO-CN) heterojunction composite photocatalysts were prepared via in situ formation of InVO4 nanoparticles on the lamellar structure of graphite carbon nitride (g-C3 N4 ) containing nitrogen (N) defects. Among these composites, 30% InVO-CN showed the best photoreduction performance for CO_(2) at normal temperature and pressure without sacrificial agent (carbon monoxide, CO: 20.14 μmol g–1 h–1;methane, CH4 : 3.46 μmol g–1 h–1 ), which were 1.8 and 2.8 times higher than these of pure g-C3 N4 and InVO4 . The excellent performance could be attributed to the enhancement of CO_(2) adsorption, and most importantly, the enhanced charge carrier separation and reduction capacity induced by the formation of Z-scheme heterojunction between InVO4 and g-C3 N4 . In this work, intimate heterojunction interfaces between materials were formed by introducing g-C3 N4 with defects in InVO4 , which provides a promising modification scheme.

关键词： Z-scheme heterojunction CO_(2)photoreduction g-C3N4,InVO4

Numerical analysis for cooling effect of open boundary ripped-rock embankment on Qinghai-Tibetan railway

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Science China Earth Sciences 2006年第7期49卷 764-772页

作者： LAI yuanming ZHANG mingyi LIU Zhiqiang yu Wenbing State Key Laboratory of Frozen Soil Engineering Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of Sciences Lanzhou 730000 China State Key Laboratory of Frozen Soil Engineering Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of Sciences Lanzhou 730000 China State Key Laboratory of Frozen Soil Engineering Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of Sciences Lanzhou 730000 China State Key Laboratory of Frozen Soil Engineering Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of Sciences Lanzhou 730000 China

The heat convection of fluid inside the ballast layer and ripped-rock layer, which are re- garded as porous media in railway embankment, is a process of heat and mass transfer. At present, the ripped-rock embankment, as a new type of embankment structure, has widely been used in the construction of Qinghai-Tibetan railway. However, because its ripped-rock layer is almost open in two bilateral boundaries and closed at top and bottom, and air can flow into/out of the ballast layer and ripped-rock layer, the convection and transfer heat patterns are very complicated in the embankment. Therefore, based on the temperature and geology conditions of the Qinghai-Tibetan Plateau, a nu- merical approach of the unsteady two-dimensional continuity, momentum (non-Darcy flow) and en- ergy equations of heat convection for incompressible fluid in porous media is provided to analyze the velocity and temperature characteristics of the ripped-rock embankment with different embankment heights under open boundary condition for the coming 50 years in this paper. The calculated results indicate that, due to the influence of the outside wind, the convective heat transfer mainly relies on the forced convection in the open ripped-rock embankment. Even if the air temperature will be warmed up by 2.6℃ in the coming 50 years, it still has a better cooling effect on the underlying soils and a low temperature frozen-soil core is formed in the permafrost below it if the embankment is constructed in the regions whose present mean annual air temperature is ?4.0℃. Furthermore, the cooling effect of high ripped-rock embankment is better than that of low embankment. This is because the wider bot- tom of high embankment has a more influence dimension on the underlying frozen soil. However, cardinal winds on the Qinghai-Tibetan Plateau disturb its convection pattern, so that an asymmetric temperature distribution occurs under high embankment and it is possible to induce a transverse un- even deformation of embankment, but no similar situation occurs u

关键词： open boundary, ripped-rock embankment, cooling effect, Qinghai-Tibetan railway.

NaGd0.4Eu0.6Mg1-xZnxWO6 solid solution red phosphors:Microstructure variation and luminescence enhancement induced by Zn2+-doping

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Journal of Rare Earths 2024年第7期42卷 1224-1232页

作者： yu Gao Jiayang Liao mingyi Zhang Qingmei Tang Ting Zhou Mengjiao Liu Yan Zhao Xin Lai Daojiang Gao College of Chemistry and Materials Science Sichuan Normal University

Red phosphor is an important component of the phosphor-converted white light-emitting diodes（pcWLEDs）.The development of the novel red phosphor with excellent luminescence properties is of great significance for high performance WLEDs.In this study,NaGd0.4Eu0.6Mg1-xZnxWO6red phosphors with excellent luminescence properties were successfully synthesized and systematically investigated.Our results show that the Zn2+-doping concentration has significant effect on the microstructures and luminescence properties of the NaGd0.4Eu0.6Mg1-xZnxWO6phosphors.The NaGd0.4Eu0.6Mg1-xZnxWO6（0≤x≤0.7） samples are well crystallized pure solid solution sub-microcrystals,whereas the phase purity gradually decreases at 0.70.4Eu0.6Mg1-xZnxWO6（00.4Eu0.6MgWO6,and the optimized NaGd0.4Eu0.6Mg0.9Zn0.1WO6phosphor possesses the best luminescence properties including thermal stability,CIE chromaticity coordinate,life time and quantum yield.The packaged WLED using NaGd0.4Eu0.6Mg0.9Zn0.1WO6phosphor emits bright white light with higher CRI,lower CCT,and chromaticity coordinate close to the pure white light.The developed NaGd0.4Eu0.6Mg1-xZnxWO6phosphors have potential application in lighting and display.This work can offer an effective strategy for boosting luminescence properties of tungstate phosphors with the double perovskite structure.

关键词： Double perovskite Luminescence Microstructure Rare earths Tungstate phosphor Zn2+-doping

Quantum Spin Exchange Interactions to Accelerate the Redox Kinetics in Li–S Batteries

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Nano-Micro Letters 2024年第5期16卷 370-383页

作者： yu Du Weijie Chen yu Wang yue yu Kai Guo Gan Qu Jianan Zhang Key Laboratory of Advanced Energy Catalytic and Functional Materials Preparation of Zhengzhou City College of Materials Science and EngineeringZhengzhou UniversityZhengzhou 450001People’s Republic of China

Spin-engineering with electrocatalysts have been exploited to suppress the“shuttle effect”in Li–S batteries.Spin selec-tion,spin-dependent electron mobility and spin potentials in activation barriers can be optimized as quantum spin exchange interactions lead-ing to a significant reduction of the electronic repulsions in the orbitals of catalysts.Herein,we anchor the MgPc molecules on fluorinated carbon nanotubes(MgPc@FCNT),which exhibits the single active Mg sites with axial displacement.According to the density functional theory calculations,the electronic spin polarization in MgPc@FCNT not only increases the adsorption energy toward LiPSs intermediates but also facilitates the tunneling process of electron in Li–S batter-ies.As a result,the MgPc@FCNT provides an initial capacity of 6.1 mAh cm^(-2) even when the high sulfur loading is 4.5 mg cm^(-2),and still maintains 5.1 mAh cm^(-2) after 100 cycles.This work provides a new perspective to extend the main group single-atom catalysts enabling high-performance Li–S batteries.

关键词： Metal phthalocyanines Spin polarization Electrocatalysis Li–S batteries

Light People:Professor Laura Na Liu

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Light(Science & Applications) 2024年第2期13卷 184-189页

作者： Hui Wang Cun yu Changchun Institute of Optics Fine Mechanics and PhysicsChinese Academy of Sciences130033ChangchunChina

Editorial The DNA nanotechnology outlines a new chapter in biological sciences,opening a new era of scientific and technological advancements.A pioneer of DNA nanotechnology,Professor Liu from the University of Stuttgart in Germany,our latest Light People,has been working at the interface,where nanophotonics meets biology and chemistry.On the path of scientific explorations.

关键词： chemistry. advancement pioneer

Macroporous Directed and Interconnected Carbon Architectures Endow Amorphous Silicon Nanodots as Low‑Strain and Fast‑Charging Anode for Lithium‑Ion Batteries

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Nano-Micro Letters 2024年第5期16卷 333-351页

作者： Zhenwei Li Meisheng Han Peilun yu Junsheng Lin Jie yu Guangdong Provincial Key Laboratory of Semiconductor Optoelectronic Materials and Intelligent Photonic Systems Shenzhen Engineering Lab for Supercapacitor MaterialsSchool of Material Science and EngineeringHarbin Institute of TechnologyShenzhenUniversity TownShenzhen 518055People’s Republic of China Songshan Lake Materials Laboratory Dongguan Dongguan 523808GuangdongPeople’s Republic of China Department of Mechanical and Energy Engineering Southern University of Science and TechnologyShenzhen 518055People’s Republic of China

Fabricating low-strain and fast-charging silicon-carbon composite anodes is highly desired but remains a huge challenge for lithium-ion batteries.Herein,we report a unique silicon-carbon composite fabricated by uniformly dis-persing amorphous Si nanodots(SiNDs)in carbon nanospheres(SiNDs/C)that are welded on the wall of the macroporous carbon framework(MPCF)by vertical graphene(VG),labeled as MPCF@VG@SiNDs/C.The high dispersity and amor-phous features of ultrasmall SiNDs(~0.7 nm),the flexible and directed electron/Li+transport channels of VG,and the MPCF impart the MPCF@VG@SiNDs/C more lithium storage sites,rapid Li+transport path,and unique low-strain property during Li+storage.Consequently,the MPCF@VG@SiNDs/C exhibits high cycle stability(1301.4 mAh g^(-1) at 1 A g^(-1) after 1000 cycles without apparent decay)and high rate capacity(910.3 mAh g^(-1),20 A g^(-1))in half cells based on industrial electrode standards.The assembled pouch full cell delivers a high energy density(1694.0 Wh L^(-1);602.8 Wh kg^(-1))and an excellent fast-charging capability(498.5 Wh kg^(-1),charging for 16.8 min at 3 C).This study opens new possibilities for preparing advanced silicon-carbon com-posite anodes for practical applications.

关键词： Amorphous Si nanodots Low-strain Fast-charging Lithium-ion batteries

Numerical Analysis for Temperature Characteristics of Open Boundary Crushed-rock Embankment on Qinghai-Tibet Railway

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工程科学（英文版） 2006年第2期4卷 134-142页

作者： Lai yuanming Zhang mingyi Liu Zhiqing yu Wenbing State Key Laboratory of Frozen Soil Engineering Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000

At present, in order to protect the stability of permafrost beneath emban kment, the crushed-rock emban kment, as a new type of emban kment structure, has widely been used in the construction of Qinghai-Tibet Railway. Its crushed-rock layer is almost open in tow bilateral boundaries and closed at top and bottom, and air can flow into/out of the ballast layer and crushed-rock layer. Therefore, the convection and transfer heat patterns are very complicated in the ballast layer and crushed-rock layer of the emban kment, which are regarded as porous media. In this paper, based on the wind, temperature and geology conditions of Qinghai-Tibet Plateau, a numerical approach of the unsteady two-dimensional continuity, momentum (non-Darcy flow) and energy equations of heat convection for incompressible fluid in porous media is provide to analyse the velocity and temperature characteristics of the crushed-rock emban kment with different emban kment heights under open boundary condition for the coming 50 years. The calculated results indicate that, due to the influence of the external wind, the convective heat transfer mainly relies on the forced convection in the open crushed-rock emban kment. Even if the air temperature will be warmed up by 2.6℃ in the coming 50 years, it still has a better cooling effect on the underlying soils and a low temperature frozen-soil core is formed in the permafrost below it if the emban kment is constructed in the regions whose present mean annual air temperature is -4.0℃. Furthermore, the cooling effect of high crushed-rock emban kment is better than that of low emban kment. This results from the fact that the wider bottom of high emban kment has a more influence dimension on the underlying frozen soil. However, cardinal winds on Qinghai-Tibet Plateau disturb its convection pattern, so that an asymmetric temperature distribution occurs under high emban kment and it is possible to induce a transverse uneven deformation of emban kment, but no similar situation occurs under low emban kment. This

关键词：青藏铁路开放边界碎石堤防温度特性数值分析

Linear-Quadratic Pareto Cooperative Game for Mean-Field Backward Stochastic System

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Journal of Systems Science & Complexity 2024年第3期37卷 947-964页

作者： WANG yu School of Control Science and Engineering Shandong UniversityJinan 250061China

This paper focuses on a Pareto cooperative differential game with a linear mean-field backward stochastic system and a quadratic form cost functional. Based on a weighted sum optimality method, the Pareto game is equivalently converted to an optimal control problem. In the first place,the feedback form of Pareto optimal strategy is derived by virtue of decoupling technology, which is represented by four Riccati equations, a mean-field forward stochastic differential equation(MF-FSDE),and a mean-field backward stochastic differential equation(MF-BSDE). In addition, the corresponding Pareto optimal solution is further obtained. Finally, the author solves a problem in mathematical finance to illustrate the application of the theoretical results.

关键词： Backward stochastic differential equation linear-quadratic control mean-field Pareto optimality

Effect of relative humidity on the desulfurization performance of calcium-based desulfurizer

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Journal of Environmental Sciences 2024年第4期138卷 179-188页

作者： Juan Lǖ yu Fu Haiyan yu HuanWang Zhe Wang Haiyan Chen School of Environment and Resource Southwest University of Science and TechnologyMianyang 621010China Guangyuan Emergency Management bureau Guangyuan 628000China

Low desulfurization efficiency impedes the wide application of dry desulfurization technology,which is a low-cost and simple process,and one significant solution is the development and manufacture of high-performance desulfurizers.In this study,firstly,a steam jet mill was used to digest quicklime;then,we utilized numerical simulation to study the flow field distribution and analyze the driving factors of quicklime digestion;and lastly,the desulfurization performance of the desulfurizer was evaluated under different relative humidities.The results show that the desulfurizer prepared via the steam jet mill had better apparent activity than traditional desulfurizers.Also,the entire jet flow field of the steam jet mill is in a supersonic and highly turbulent flow state,with high crushing intensity and good particle acceleration performance.Sufficient contact with the nascent surface maximizes the formation of slaked lime.The experiments demonstrated that the operating time with 100%desulfurization efficiency and the“break-through”time for the desulfurizer prepared via the steam jet mill is longer than that of traditional desulfurizers,and has significant advantages,especially at low flue gas relative humidity.Compared with traditional desulfurizers,the desulfurizer prepared via steam jet mill expands the range of acceptable flue gas temperature,and the failure temperature is 1.625 times that of traditional desulfurizers.This work breaks through the technical bottleneck of low dry desulfurization efficiency,which is an important step in pushing forward the application of dry desulfurization.

关键词： Dry desulfurization Relative humidity Desulfurization efficiency High-efficiency desulfurizer Quicklime digestion

Visible Light-Induced[3+2]Annulation Reaction of Alkenes with Vinyl Azides:Direct Synthesis of Functionalized Pyrroles

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Chinese Journal of Chemistry 2024年第2期42卷 151-156页

作者： Ming Yang Xin-yu Wang Jie Wang yu-Long Zhao Jilin Province Key Laboratory of Organic Functional Molecular Design&Synthesis Faculty of ChemistryNortheast Normal UniversityChangchunJilin 130024China

A photocatalytic[3+2]annulation of alkenes with vinyl azides was developed under irradiation by visible light in the presence of organic dye photocatalysts.Broad substrate scope and high functional group tolerance were demonstrated by more than 50 examples.The reaction provides a novel and efficient method for the synthesis of polyfunctionalized pyrroles under very mild metal-free conditions without other additives.

关键词： Photocatalysis Vinyl azides Alkenes Pyrroles Annulation Radical reactions