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Realizing high initial Coulombic efficiency in manganese-based layered oxide cathodes for sodium-ion batteries via P2/O'3 biphasic structure optimization

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Rare Metals 2024年第5期43卷 2093-2102页

作者： bo Peng Zi-Hao Zhou Ping xuan Jie Xu Lian-bo Ma School of Materials Science and Engineering Anhui University ofTechnologyMa'anshan 243002China Anhui Product Quality Supervision&Inspection Research Institute Hefei 230051China

Mn-based layered oxides are among the most promising cathode materials for sodium-ion batteries owing to the advantages of abundance,environmenta friendliness,low cost and high specific capacity.P2 and O'3 are two representative structures of Mn-based layered ***,the P2 structure containing insufficien Na generally exhibits low initial charge capacity,while O'3structure with sufficient Na delivers high initial charge capacity but poor cycle *** study prepared a multitude of Na_(x)MnO_(2)(x=0.7,0.8,0.9)cathode materials with varying P2/O'3 ratios and further investigated their electrochemical *** optimized Na_(0.8)MnO_(2) comprising 69.9 wt%O'3 and 30.1 wt%P2 phase,exhibited relatively balanced specific capacity,Coulombic efficiency and cycle ***,it achieved a high specific capacity of 128.9 mAh·g^(-1) with an initia Coulombic efficiency of 98.2%in half-cell configuration The Na_(0.8)MnO_(2)//hard carbon full cell also achieved a high specific capacity of 126.7 mAh·g^(-1) with an initia Coulombic efficiency of 98.9%.Moreover,the capacity fading mechanism was revealed by combining in-situ and ex-situ X-ray *** findings of this study provide theoretical guidance for further modification design of Mnbased layered cathodes.

关键词： Sodium-ion batteries Cathode materials Mn-based layered oxides P2/0'3 composites

C-S coupling with nitro group as leaving group via simple inorganic salt catalysis

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Chinese Chemical Letters 2020年第1期31卷 84-90页

作者： Maojie xuan Chunlei Lu bo-Lin Lin School of Chemical and Environmental Engineering Shanghai Institute of TechnologyShanghai 201418China School of Physical Science and Technology(SPST) ShanghaiTech UniversityShanghai 201210China

An efficient and practical synthetic protocol to synthesize nonsymmetrical aryl thioethers by nucleophilic aromatic substitution(S_NAr)reaction of nitroarenes by thiols with potassium phosphate as the catalyst is *** moderate to strong electron-withdrawing functional groups are tolerated by the system to provide thioethers in a good to excellent *** also showed that the present method allows access to 3 drug examples in a short reaction ***,mechanistic studies suggest that the reaction may form the classic Meisenheimer complex through a two-step additionelimination mechanism.

关键词： Inorganic-salt catalysis Nucleophilic aromatic substitution C-S bond Denitrification coupling Kinetic isotope effect Meisenheimer complex

Novel Catalytic Hydrodechlorination of CCl_2F_2 over Supported PdCl_2-(n-C_4H_9)_4N^+Cl^- Molten salts

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Chinese Chemical Letters 2001年第6期12卷 533-536页

作者： Yu Cai cao xuan Zhen JIANG Department of Chemistry Zhejiang UniversityHangzhou 310027

A novel supported liquid phase film catalyst: Supported PdCl2-(n-C4H9),N+Cl- molten salts was found to be an effective catalyst with good stability for selective hydrodechlorination of CCl2F2 (CFC-12) to its alternatives CH2F2 and CHClF2. Addition of CoCl2, GaCl3 and CuCl2 to PdCl2-(n-C4H9),N+Cl- modifies the catalytic performance of supported molten salts.

关键词： Liquid film catalyst palladium chloride tetrabutylammonium chloride molten salts CFC-12 hydrodechlorination HFC-32 HCFC-22

Numerical study on the effects of progressive gravity waves on turbulence

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Journal of Hydrodynamics 2016年第6期28卷 1011-1017页

作者： Anqing(Elliott) xuan Bingqing DENG Tao cao Lian SHEN Department of Mechanical Engineering and Saint Anthony Falls Laboratory University of Minnesota

The wind-wave-ocean system, which contains complex interactive processes, is of great importance for the momentum, heat and mass transport in the atmosphere and ocean and at their interface. In this work, we perform wave-coupled phase-resolved numerical simulations to investigate the effect of progressive gravity waves on wind and ocean turbulence. Initially homogeneous turbulence under a finite-amplitude monochromatic surface wave is simulated to reveal how the wave influences the subsurface turbulence. For the interaction between wind-driven waves and shear turbulence in the ocean, new wave-phase-resolved simulation approaches are developed to capture Langmuir cells. Lastly, wind turbulence over one and two progressive waves is simulated to elucidate the dynamics of turbulence coherent structures impacted by surface waves for improved understanding of wind-wave growth mechanism.

关键词： wave-ocean interaction Langmuir circulation wave-wind interaction numerical simulation

The Early Permian Woniusi Flood Basalts from the Baoshan Terrane, SW China: Petrogenesis and Geodynamic Implications

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Acta Geologica Sinica(English Edition) 2020年第6期94卷 2091-2114页

作者： cao Jun ZHANG Gaizhi WANG xuan CHEN Jun State Key Laboratory of Nuclear Resources and Environment East China University of TechnologyNanchang 330013China Shandong Key Laboratory of Depositional Mineralization&Sedimentary Minerals Shandong University of Science and TechnologyQingdaoShandong 266590China School of Earth Sciences East China University of TechnologyNanchang 330013China State Key Laboratory of Isotope Geochemistry Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640China

The Woniusi flood basalts from the Baoshan terrane,SW China,represent a significant eruption of volcanic rocks which were linked to the Late Paleozoic rifting of the Cimmeria from the northern margin of East ***,the precise mechanism for the formation and propagation of the rifting is still in *** we report 40 Ar/39 Ar dating,whole-rock geochemistry,and Sr-Nd-Pb isotopes for the Woniusi basalts from the Baoshan terrane of SW China,with the aim of assessing if a mantle plume was related to the formation of the continent Cimmeria.40 Ar/39 Ar dating of the Woniusi basalts yielded ages of 279.3±1.1 Ma and 273.9±1.5 Ma,indicating they were emplaced during the Early ***-rock geochemistry shows that these basalts have subalkaline tholeiitic affinity,low Ti O2(1.2-2.2 wt%),and fractionated chondrite-normalized LREE and nearly flat HREE patterns[(La/Yb)N=2.86-5.77;(Dy/Yb)N=1.21-1.49]with noticeable negative Nb and Ta anomalies on the primitive mantle-normalized trace element ***ε(Nd)(t)values(-4.76 to+0.92)and high(206 Pb/204 Pb)i(18.40-18.66)along with partial melt modeling indicates that the basalts were likely derived from a sub-continental lithospheric mantle(SCLM)source metasomatized by subduction-related *** the basis of a similar emplacement age to the Panjal basalts and Qiangtang mafic dykes and flood basalts in the Himalayas,combined with a tectonic reconstruction of Gondwana in the Early Permian,we propose that the large-scale eruption of these basalts and dykes was related to an Early Permian mantle plume that possibly initiated the rifting on the northern margin of East Gondwana.

关键词： geochemistry flood basalts Early Permian Baoshan Gondwana

Research on an innovative structure of an open-ribbed steel-ultra-high performance concrete composite bridge deck

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Frontiers of Structural and Civil Engineering 2024年第5期18卷 716-730页

作者： Xudong SHAO xuan SUN Deqiang ZOU Junhui cao Chuanqi YANG School of Civil Engineering Hunan UniversityKey Laboratory for Wind and Bridge Engineering of Hunan ProvinceChangsha 410082China China Construction Fifth Engineering Division Co. Ltd.Changsha 410004China

To completely solve the problem of fatigue cracking issue of orthotropic steel bridge decks(OSDs),the authors proposed a steel–ultra-high performance concrete(UHPC)lightweight composite deck(LWCD)with closed ribs in *** on the successful application of that LWCD,an adaptation incorporating an innovative composite deck structure,i.e.,the hot-rolled section steel–UHPC composite deck with open ribs(SSD)is proposed in this paper,aiming to simplify the fabrication process as well as to reduce the cost of *** on a long-span cable-stayed bridge,a design scheme is proposed and is compared with the conventional OSD ***,a finite element(FE)calculation is conducted to reflect both the global and local behavior of the SSD scheme,and it is found that the peaked stresses in the SSD components are less than the corresponding allowable values.A static test is performed for an SSD strip specimen to understand the anti-cracking behavior of the UHPC layer under negative bending *** static test results indicate that the UHPC layer exhibited a satisfactory tensile toughness,the UHPC tensile strength obtained from the test is 1.8 times the calculated stress by the FE model of the real *** addition,the fatigue stresses of typical fatigue-prone details in the SSD are calculated and evaluated,and the influences of key design parameters on the fatigue performance of the SSD are *** to the fatigue results,the peaked stress ranges for all of the 10 fatigue-prone details are within the corresponding constant amplitude fatigue *** a fatigue test is carried out for another SSD strip specimen to explore the fatigue behavior of the fillet weld between the longitudinal and transverse *** specimen failed at the fillet weld after equivalent 47.5 million cycles of loading under the design fatigue stress range,indicating that the fatigue performance of the SSD could meet the fatigue design *** calculations and experim

关键词： steel-ultra-high performance concrete composite deck open rib strip model test static and fatigue performance orthotropic steel deck

;unctional metabolomics： from biomarker ：liscovery to metabolome reprogramming

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Protein & Cell 2015年第9期6卷 628-637页

作者： bo Peng Hui Li xuan-Xian Peng Center for Proteomics and Metabolomics State Key Laboratory of Biocontrol School of Life Sciences MOE Key Lab Aquat Food Safety School of Life Sciences Sun Yat-sen University Guangzhou 510275 China Molecular Foundry Lawrence Berkeley National Laboratory Berkeley CA 94720 USA

Metabolomics is emerging as a powerful tool for studying metabolic processes, identifying crucial biomarkers responsible for metabolic characteristics and revealing metabolic mechanisms, which construct the content of discovery metabolomics. The crucial biomarkers can be used to reprogram a metabolome, leading to an aimed metabolic strategy to cope with alteration of internal and external environments, naming reprogramming metabo- Iomics here. The striking feature on the similarity of the basic metabolic pathways and components among vastly different species makes the reprogramming metabolomics possible when the engineered metabolites play biological roles in cellular activity as a substrate of enzymes and a regulator to other molecules including proteins. The reprogramming metabolomics approach can be used to clarify metabolic mechanisms of responding to changed internal and external environmental factors and to estab- lish a framework to develop targeted tools for dealing with the changes such as controlling and/or preventing infec- tion with pathogens and enhancing host immunity against pathogens. This review introduces the current state and trends of discovery metabolomics and reprogramming metabolomics and highlights the importance of repro- gramming metabolomics.

关键词： reprogrammingregulationmetabolomics discovery metabolomicsmetabolomics metabolic strategy metabolic

Structural optimization strategy of pipe isolation tool by dynamic plugging process analysis

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Petroleum Science 2021年第6期18卷 1829-1839页

作者： Ting-Ting Wu Hong Zhao bo-xuan Gao Fan-bo Meng College of Mechanical and Transportation Engineering China University of PetroleumBeijing102249China

During the pipeline plugging process,both the pipeline and the pipe isolation tool(PIT)will be greatly damaged,due to the violent vibration of the flow *** this study,it was proposed for the first time to reduce the vibration of the flow field during the plugging process by optimizing the surface structure of the ***,the central composite design(CCD)was used to obtain the optimization schemes,and the drag coefficient and pressure coefficient were proposed to evaluate the degree of flow field ***,a series of computational fluid dynamics(CFD)simulations were performed to obtain the drag coefficient and pressure coefficient during dynamic *** the mathematical model of drag coefficient and pressure coefficient with the surface structure of the PIT were established ***,a modified particle swarm optimization(PSO)was applied to predict the optimal value of the surface structure of the ***,an experimental rig was built to verify the effectiveness of the *** results showed that the improved method could reduce the flow field vibration by 49.56%.This study provides a reference for the design of the PIT surface structure for flow field vibration technology.

关键词： Pipe isolation tool Dynamic analysis Drag coefficient Pressure coefficient Modified particle swarm optimization algorithm

Characterization of size-resolved effective density of atmospheric particles in an urban atmosphere in Southern China

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Journal of Environmental Sciences 2024年第7期141卷 194-204页

作者： Tingting Xie Liming cao Jinyi Zheng Peng xuan Xiaofeng Huang Laboratory of Atmospheric Observation Supersite School of Environment and EnergyPeking University Shenzhen Graduate SchoolShenzhen 518055China

Effective density(ρ_(eff))is one of the most important physical properties of atmospheric particles,providing important references in exploring the emissions and aging processes of fresh *** this study,a combined system of differential mobility analyzer,centrifugal particle mass analyzer,and condensation particle counter was used to periodically measure theρ_(eff)of atmospheric particles in Shenzhen from Oct.2021 to *** showed that theρ_(eff)of particles with various size presented a bimodal distribution,which could be divided into main density(ρ_(m),main peak,corresponding to relatively dense particles after aging)and sub density(ρ_(s),sub peak,corresponding to fresh particles).The occurrence frequencies ofρ_(s)of particles with diameters of 50 and 80 nm were less than 20%,but were as high as about 40%of that with diameters from 120 to 350 ***ρ_(m)showed increasing trend with the size of particles,whileρ_(s)decreased as the increasing of the size of ***ρ_(eff)on pollution day varied significantly with chemical *** increasing of the proportion of sulfate could promote the increasing ofρ_(eff),while black carbon and organic matter caused opposite effects,which may be related to various factors,including the difference of the material density and morphology of various chemical ***ρ_(eff)of 50,80 and 120 nm particles decreased considerably during the new particle formation event,indicating that organic condensation was an important contributor to new particle growth.

关键词： DMA-CPMA-CPC Effective density Main/sub density Size distribution