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Branched Co3O4/Fe2O3 nanowires as high capacity lithium-ion battery anodes

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Nano Research 2013年第3期6卷 167-173页

作者： Hao Wu ming xu Yongcheng wang Gengfeng Zheng Laboratory of Advanced Materials Department of Chemistry Fudan University Shanghai200433 China

We report a facile, two-step hydrothermal synthesis of a novel Co304/a-Fe2O3 branched nanowire heterostructure, which can serve as a good candidate for lithium-ion battery anodes with high Li＋ storage capacity and stability. The single-crystalline, primary C0304 nanowire trunk arrays directly grown on Ti substrates allow for efficient electrical and ionic transport. The secondary a-Fe2O3 branches provide enhanced surface area and high theoretical Li＋ storage capacity, and can also serve as volume spacers between neighboring Co3O4 NW arrays to maintain electrolyte penetration as well as reduce the aggregation during Li＋ intercalation, thus leading to improved electrochemical energy storage performance.

关键词： Co3O4 a-Fe2O3 nanowire branched lithium-ion battery Nyquist plot

Temporal variations of reference evapotranspiration and its sensitivity to meteorological factors in Heihe River Basin, China

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Water Science and Engineering 2015年第1期8卷 1-8页

作者： Jie Zhao Zong-xue xu De-peng Zuo xu-ming wang College of Water Sciences Beijing Normal University

On the basis of daily meteorological data from 15 meteorological stations in the Heihe River Basin （HRB） during the period from 1959 to 2012, long-term trends of reference evapotranspiration （ET0） and key meteorological factors that affect ET0 were analyzed using the Mann- Kendall test. The evaporation paradox was also investigated at 15 meteorological stations. In order to explore the contribution of key meteo- rological factors to the temporal variation of ET0, a sensitivity coefficient method was employed in this study. The results show that：（1） mean annual air temperature significantly increased at all 15 meteorological stations, while the mean annual ET0 decreased at most of sites; （2） the evaporation paradox did exist in the HRB, while the evaporation paradox was not continuous in space and time; and （3） relative humidity was the most sensitive meteorological factor with regard to the temporal variation of ET0 in the HRB, followed by wind speed, air temperature, and solar radiation. Air temperature and solar radiation contributed most to the temporal variation of ETo in the upper reaches; solar radiation and wind speed were the determining factors for the temporal variation of ET0 in the middle-lower reaches.

关键词： Reference evapotranspiration Evaporation paradox Meteorological factor Heihe River Basin

Handover with resource pre-allocation in the OFDMA systems

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The Journal of China Universities of Posts and Telecommunications 2007年第4期14卷 27-31,52页

作者： LI ming-ju xu Ning wang Ying ZHANG Ping Key Laboratory of Universal Wireless Communications (Beijing University ofPosts and Telecommunications) Ministry of Education Wireless TechnologyInnovation Institute Beijing 100876. China

This article proposed a new handover algorithm for beyond the third generation （B3G） systems with an orthogonal frequency division multiple access （OFDMA） downlink. In the proposed algorithm, handover mobile termination （MT） chooses a subchannel set in the candidate cells by a subchannel booking rule, based on the terminal speed and the subchannel＇s channel state information （CSI）. Moreover, the handover decision is made after analyzing if at least one candidate cell can reserve the subchannel set for the handover user. Simulation results show that the algorithm reduces the number of handovers and guarantees the quality of service （QoS） for the handover users. It yields better system performance in the OFDMA systems.

关键词： handover OFDMA resource preallocation subchannel booking rule CSI

THE BOUNDEDNESS OF BILINEAR SINGULAR INTEGRAL OPERATORS ON SIERPINSKI GASKETS

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Analysis in Theory and Applications 2011年第1期27卷 92-100页

作者： ming xu Shengmei wang Jinan University China

In the paper we give the boundedness estimate of bilinear singular integral operators on Sierpinski gasket inspired from [ 1 ].

关键词： boundedness bilinear singular integral Sierpinski gaskets

Climate change trend and its effects on reference evapotranspiration at Linhe Station, Hetao Irrigation District

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Water Science and Engineering 2014年第3期7卷 250-266页

作者： xu-ming wang Hai-jun LIU Li-wei ZHANG Rui-hao ZHANG College of Water Sciences Beijing Normal University

Linhe National Meteorological Station, a representative weather station in the Hetao Irrigation District of China, was selected as the research site for the present study. Changes in climatic variables and reference evapotranspiration （ET0 ）（estimated by the Penman-Monteith method） were detected using Mann-Kendall tests and Sen＇s slope estimator, respectively. The authors analyzed the relationship between the ET0 change and each climatic variable＇s change. From 1954 to 2012, the air temperature showed a significant increasing trend, whereas relative humidity and wind speed decreased dramatically. These changes resulted in a slight increase in ETo. The radiative component of total ET0 increased from 50% to 57%, indicating that this component made a greater contribution to the increase in total ETo than the aerodynamic component, especially during the crop growing season （from April to October）. The sensitivity analysis showed that ETo in Hetao is most sensitive to mean daily air temperature （11.8%）, followed by wind speed （-7.3%） and relative humidity （4.8%）. Changes in sunshine duration had only a minor effect on ET0 over the past 59 years.

关键词： climatic variables reference evapotranspiration change trend Mann-Kendall test sensitivity analysis

Strain-tuned magnetic properties in(Ga,Fe)Sb:First-principles study

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Chinese Physics B 2021年第9期30卷 388-392页

作者： Feng-Chun Pan xue-Ling Lin xu-ming wang School of Physics and Electronic-Electrical Engineering Ningxia UniversityYinchuan 750021China

In view of the importance of enhancing ferromagnetic(FM)coupling in dilute magnetic semiconductors(DMSs),the effects of strain on the electronic structures and magnetic properties of(Ga,Fe)Sb were examined by a first-principles *** results of the investigation indicate that Fe_(Ga) substitution takes place in the low-spin state(LSS)with a total magnetic moment of 1μB in the strain range of-3%to 0.5%,which transitions to the high-spin state(HSS)with a total magnetic moment of 5μB as the strain changes from 0.6%to 3%.We attribute the changes in the amount and distribution of the total moment to the influence of the crystal field under different *** FM coupling is strongest under a strain of about 0.5%,but gradually becomes weaker with increasing compressive and tensile *** magnetic coupling mechanism is discussed in *** results highlight the important contribution of strain to magnetic moment and FM interaction intensity,and present an interesting avenue for the future design of high Curie temperature(TC)materials in the(Ga,Fe)Sb system.

关键词： GaSb Fe ferromagnetism strain

Amino acids modified nanoscale zero-valent iron:Density functional theory calculations,experimental synthesis and application in the Fenton-like degradation of organic solvents

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Journal of Environmental Sciences 2024年第1期135卷 296-309页

作者： Xingchen Yang Fucheng ming Jianlong wang Lejin xu Department of Nuclear Engineering and Technology School of Energy and Power EngineeringHuazhong University of Science and TechnologyWuhan 430074China China-EU Institute for Clean and Renewable Energy Huazhong University of Science and TechnologyWuhan 430074China Institute of Nuclear and New Energy Technology Key Laboratory of Advanced Reactor Engineering and Safety of Ministry of EducationTsinghua UniversityBeijing 100084China Beijing Key Laboratory of Radioactive Wastes Treatment Tsinghua UniversityBeijing 100084China

To improve the adsorption and catalytic performance of heterogeneous Fenton-like catalysts for oil wastes,amino acids were used to modify nanoscale zero-valent iron(AA@Fe^(0)),which were applied in the Fenton-like degradation of organic solvents(tributyl phosphate and n-dodecane,named TBP and DD).Twelve amino acids,i.e.,glycine(Gly),alanine(Ala),leucine(Leu),proline(Pro),phenylalanine(Phe),methionine(Met),cysteine(Cys),asparagine(Asn),serine(Ser),glutamic acid(Glu),lysine(Lys)and arginine(Arg),were selected and calculated by density functional theory(DFT).The optimized structure,charge distribution,the highest occupied molecular orbital(HOMO),the lowest unoccupied molecular orbital(LUMO),interaction region indicator(IRI)isosurface map and adsorption energy of AA@Fe^(0),AA@Fe^(0)-TBP and AA@Fe^(0)-DD were studied,which indicated that Fe is more likely to approach and charge transfer with-COO and-NH_(3) on theα-carbon of amino *** is strong attraction between Fe and–COO,and Van der Waals force between Fe and-NH_(3),*** the interaction of AA@Fe^(0)with TBP and DD,Van der Waal force plays an important ***@Fe^(0)was synthesized in laboratory and characterized to investigate physicochemical *** Fenton-like degradation of organic solvents,the change of COD in water phase during the degradation process as well as the volume of the organic phase after the reaction were *** results of calculations combined with experiments showed that Ser-modified Fe^(0)performed the best in these amino acids,with 98%removal of organic solvents.A possible catalytic mechanism was proposed in which amino acids acted a linking role between Fe and organic solvents,activating H_(2)O_(2)to generate hydroxyl radicals for the degradation of organic solvents.

关键词： Amino acids Nanoscale zero-valent iron Density functional theory Organic solvents Fenton-like degradation

Synthesis,Style Editing,and Animation of 3D Cartoon Face

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Tsinghua Science and Technology 2024年第2期29卷 506-516页

作者： ming Guo Feng xu Shunfei wang Zhibo wang ming Lu Xiufen Cui Xiao Ling School of Software and BNRist Tsinghua UniversityBeijing 100084China Department of Multimedia and Smart Guangdong OPPO Mobile Telecommunications Corp.Ltd.Dongguan 523860China Intel Labs IntelBeijing 100089China

As a popular kind of stylized face,cartoon faces have rich application *** is challenging to create personalized 3D cartoon faces directly from 2D real ***,in order to adapt to more application scenarios,automatic style editing,and animation of cartoon faces is also a crucial problem that is urgently needed to be solved in the industry,but has not yet had a perfect *** solve this problem,we first propose“3D face cartoonizer”,which can generate high-quality 3D cartoon faces with texture when fed into 2D facial *** contribute the first 3D cartoon face hybrid dataset and a new training strategy which first pretrains our network with low-quality triplets in a reconstruction-then-generation manner,and then finetunes it with high-quality triplets in an adversarial manner to fully leverage the hybrid ***,we implement style editing for 3D cartoon faces based on k-means,which can be easily achieved without retrain the neural *** addition,we propose a new cartoon faces'blendshape generation method,and based on this,realize the expression animation of 3D cartoon faces,enabling more practical *** dataset and code will be released for future research.

关键词： cartoon 3D face animation computer graphics

Microstructure and property of laser additive manufactured alloy Ti-6Al-2V-1.5Mo-0.5Zr-0.3Si after aged at different temperatures

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Rare Metals 2024年第5期43卷 2275-2281页

作者： Guo-Chao Li xu Cheng Hua-ming wang National Engineering Laboratory of Additive Manufacturing for Large Metallic Components and Engineering Research Center of Ministry of Education on Laser Direct Manufacturing for Large Metallic Components School of Materials Science and EngineeringBeihang UniversityBeijing 100191China

The solid solution and aging treatment for conventional manufacturing processes might not be suitable for laser additive manufactured titanium alloys due to the different lamellar *** this study,the influence of aging temperatures(600,700 and 800°C)on microstructure and mechanical properties of titanium alloy Ti-6Al-2V-1.5Mo-0.5Zr-0.3Si was *** results indicate that after solid solution treatment at 970°C followed by water quenching,the alloy mainly consists of coarsening lamellar a phase in martensite α' *** at 600°C will not change the size of primary lamellar α phase but lead to huge amount of secondary a phases(α_(s))generating with very fine *** increasing the aging temperature,the number of α_(s) decreases but with coarsened *** aged at 800°C,the width of the asphase reaches 350 nm,almost 7 times wider than that aged at 600°*** changing size of α_(s) obviously influences the property of the *** fine α_(s) leads to high strength and microhardness but low plasticity,and specimen aged at 700°C with suitable assize has the best comprehensive properties.

关键词： α+βtitanium alloy Laser additive manufacturing Solid solution and aging treatment Microstructure Room temperature tensile property