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Synergistic double-atom catalysts of metal-boron anchored on g-C_(2)n for electrochemical nitrogen reduction:mechanistic insight and catalyst screening

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Journal of Energy Chemistry 2023年第5期80卷 350-360,I0009页

作者： Yang Li wei An College of Chemistry and Chemical Engineering Shanghai University of Engineering ScienceShanghai 201620China

The rational design of a novel catalytic center with a sound basis remains both challenging and rewarding for the electrochemical reduction of n2(e nRR),which has provided a feasible route for achieving clean and sustainable nH3production under ambient ***,using density functional theory calculations,we dem.nstrate that hybrid metal(m)-boron(B)double-atom catalysts(DACs)embedded in gC_(2)n substrate(m-B@C_(2)n,m=3d,4d and 5d transition metals)can achieve both high catalytic activity and high selectivity in e *** proposed m-B@C_(2)n DACs have exhibited impressive feasibility and stability thanks to the resilient and robust C_(2)n substrate with abundant pyridinic n atoms distributed am.ng right-sized pore *** results reveal that like the metal center,the embedded B atom can actively involve in n≡n bond activation viaπ*-backdonation mechanism concomitant with the substantial charge transfer to adsorbed*n2,leading to sizable nAn bond ***,both adsorption energy and nAn bond length of*n2can be employed as catalytic descriptors for predicting e nRR activity in terms of the limiting potentials(UL).Using high-throughput screening method,we found that six m-B@C_(2)n candidates have stood out as the outstanding electrocatalysts for driving e nRR,namely,m=Ti(UL=0 V),mo(UL=0 V),nb(UL=-0.04 V),W(UL=-0.23 V),Zr(UL=-0.26 V),V(UL=-0.28 V).The underlying origin is attributed to the balanced and constrained n-affinity of m-B dual site working in synergy,which can thus be used as one important guide of catalyst design.

关键词： Electrocatalysis n_(2)reduction Double-atom catalyst Synergistic effect DFT

Soil Contam.nation due to Activities： A Review with E-Waste Disposal and Recycling Special Focus on China

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Pedosphere 2012年第4期22卷 434-455页

作者： ZHAnG wei-Hua WU Ying-Xini m. O. SIm.nnOT School of Environm.ntal Science and Engineering Sun Yat-sen University Guangzhou 510275 (China) Environm.ntal Science Division Oak Ridge National Laboratory Oak Ridge TN 37831 (USA) Guangdong Provincial Key Laboratory of Environm.ntal Pollution Control and Remediation Technology Guangzhou 510275 (China) Laboratoire Rdactions et Gdnie des Procgdds (LRGP) Universitd de Lorraine-CNRS (UPR 3349) 1 Rue Grandville BP20451 54001 Nancy Cedex (France)

This paper presents a review of soil contam.nation resulting from e-waste recycling activities, with a special focus on China, where m.ny data have been collected for a decade. Soils in the e-waste areas are often contam.nated by heavy metals and organic compounds, mainly polycyclic aromatic hydrocarbons （PAHs）, polybrom.nated diphenyl ethers （PBDEs）, polychlorinated and polybrom.nated biphenyls （PCBs and PBBs）, dechlorane plus （DP）, hexabromocyclododecanes （HBCDs）, polychlorinated and polybrom.nated dibenzo- p-dioxins （PCDDs and PBDDs）, and polychlorinated and polybrom.nated dibenzofurans （PCDFs and PBDFs）, while other compounds, not systematically m.nitored, can be found as well. Pollutants are generally present in mixtures, so pollution situations are complex and diversified with a gradient of contam.nation from agricultural soils to hot spots at e-waste sites and mainly in open burning areas. It has been proved that pollutants were transferred to the food chain via rice in China, and that the population was threatened since high levels of various pollutants were detected in blood, placentas, hair, etc., of residents of e-waste sites. Eventually, soil remediation techniques are reviewed. Although there are m.ny available techniques devoted to heavy metals and persistent organic pollutants, the current techniques for the e-waste sites, where these contam.nants coexist, are very sparse. Phytoremediation has been investigated and co-cropping appears as a promising approach for the slightly contam.nated agricultural soils. In some cases, different remediation techniques should be combined or trained, while the influence of coexisting contam.nants and the removal sequence of contam.nants should be considered. In hot spots, physical and chemical techniques should be used to reduce high pollution levels to prevent further pollutant dissem.nation. This review highlights the urgent needs for 1） characterization of pollution status in all the countries where e-wastes are r

关键词： co-cropping heavy metals organic compounds pollution remediation

On the methods of Beam Direction and misorientationAngle/Axis Determ.nation by Systematic Tilt

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Journal of materials Science & Technology 1999年第5期15卷 410-414页

作者： Rong, YH He, G Chen, SP Hu, GX Gao, m wei, RP Shanghai Jiao Tong Univ Sch Mat Sci & Engn Shanghai 200030 Peoples R China Lehigh Univ Dept Mech Engn & Mech Bethlehem PA 18015 USA

The methods for determ.ning electron beam direction and misorientation angle/axis of grain boundaries are described in this paper. The present methods are based on a series of diffraction spot patterns obtained by systematic tilt of the crystal, combined with simple mathematical calculations. Instead of the use of Kikuchi patterns, the limitations resulting from the visibility or sharpness of Kikuchi lines and the number of Kikuchi pole(s) existed are avoided and a sufficient accuracy of determ.nation has been achieved.

关键词： Transmission electron microscopy

Upper Cretaceous trench deposits of the neo-Tethyan subduction zone： Jiachala Formation from Yarlung Zangbo suture zone in Tibet, China

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Science China Earth Sciences 2018年第9期61卷 1204-1220页

作者： Hanpu FU Xiumian HU Erica m. CROUCH wei An Jiangang WAnG Eduardo GARZAnTI State Key Laboratory of m.neral Deposits Research School of Earth Sciences and Engineering Nanjing University Nanjing 210023 China GnS Science PO Box 30368 Lower Hurt 5040 New Zealand School of Resources and Environm.ntal Engineering Hefei University of Technology Hefei 230009 China State Key Laboratory of Lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences Bering 100029 China Departm.nt of Earth and Environm.ntal Sciences Universita di Milano-Bicocca Milano 20126 Italy

The history of convergence between the India and the Asia plates, and of their subsequent collision which triggered the Himalayan orogeny is recorded in the Yarlung Zangbo suture zone. Exposed along the southern side of the suture, turbidites of the the Jiachala Formation fed largely from the Gangdese arc have long been considered as post-collisional foreland-basin deposits based on the reported occurrence of Paleocene-early Eocene dinoflagellate cysts and pollen assemblages. Because magmatic activity in the Gangdese arc continued through the Late Cretaceous and Paleogene, this scenario is incompatible with U-Pb ages of detrital zircons invariably older than the latest Cretaceous. To solve this conundrum, we carried out detailed stratigraphic, sedim.ntological, paleontological, and provenance analyses in the Gyangze and Sajia areas of southern Tibet,China. The Jiachala Formation consists of submarine fan deposits that lie in fault contact with the Zongzhuo *** petrography together with U-Pb ages and Hf isotope ratios of detrital zircons indicate provenance from the Gangdese arc and central Lhasa terrane. Well preserved pollen or dinoflagellate cysts microfossils were not found in spite of careful research, and the youngest age obtained from zircon grain was ～84 ma. Based on sedim.ntary facies, provenance analysis and tectonic position, we suggest that the Jiachala Formation was deposited during the Late Cretaceous(~88–84 ma) in the trench formed along the southern edge of Asia during subduction of neo-Tethyan oceanic lithosphere.

关键词： Provenance analysis Trench deposits Late Cretaceous neo-Tethyan oceanic subduction Yarlung Zangbo suturezone Tibet of China

A new inclination-based method to evaluate the global geomagnetic configuration and axial dipole mom.nt

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Earth and Planetary Physics 2022年第4期6卷 359-365页

作者： KaiHua Xu Fei He Yong wei Ross n.mitchell Si Chen YuQi Wang ZhaoJin Rong Key Laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China School of Earth and Environm.nt University of LeedsLeedsLS29JTUK

The strength and configuration of the geomagnetic field control the average shape of the *** pure dipole assumption and the virtual dipole mom.nt(VDm),determ.ned by individual records,have been widely adopted to evaluate the strength of the geomagnetic field in geological ***,such an assumption might not be valid during geomagnetic transitions,such as reversals and *** traditional spherical harm.nic modeling of the geomagnetic field could be difficult to implem.nt because accurate global records are ***,we report that an empirical relationship exists between the ratio of the VDm to the true axial dipole mom.nt(VDm/ADm)and the ratio of the power of the axial dipole to that of the non-axial dipole(AD/nAD)based on a new method utilizing globally distributed inclination *** root mean square global deviation of inclination(RmSΔI)to the standard inclination distribution of the AD was fitted to the AD/nAD with a cubic polynomial by utilizing a large number of geodynamo *** with geomagnetic field models showed that the AD/nAD derived from the RmSΔI agreed well with that calculated by using the Gauss coefficients,and the estimated ADm was consistent with the true ***,the application of volcanic records during the Laschamp excursion showed the VDm might overestimate the ADm by a factor of *** new method will be useful in future studies that characterize the configuration of the geomagnetic field and the strength of the axial dipole.

关键词： axial dipole magnetic inclination virtual dipole mom.nt

ParametricVibration Analysis of Pipes Conveying Fluid by nonlinear normal modes and a numerical Iterative Approach

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Advances in Applied mathematics and mechanics 2019年第1期11卷 38-52页

作者： Feng Liang Xiaodong Yang wei Zhang Yingjing Qian Roderick V.n.melnik College of mechanical Engineering Yangzhou UniversityYangzhou 225127JiangsuChina Beijing Key Laboratory of nonlinear Vibrations and Strength of mechanical Engineering College of Mechanical Engineering and Applied ElectronicsBeijing University of TechnologyBeijing 100124China The mS2Discovery Interdisciplinary Research Institute M2NeT LaboratoryWilfrid Laurier University75 University Avenue WestWaterlooONCanadaN2L 3C5 BCAm–Basque Center for Applied mathematics E48009 BilbaoSpain

nonlinear normal modes and a numerical iterative approach are applied to study the parametric vibrations of pipes conveying pulsating fluid as an example of gyroscopic *** nonlinear non-autonomous governing equations are transformed into a set of pseudo-autonomous ones by employing the harm.nic balance *** nonlinear normal modes are constructed by the invariant m.nifold method on the state space and a numerical iterative approach is adopted to obtain numerical solutions,in which two types of initial conditions for the modal coefficients are *** results show that both initial conditions can lead to fast *** frequency-amplitude responses with some modal motions in phase space are obtained by the present iterative *** phase difference and traveling waves are found in the time-domain complex modal analysis.

关键词： Gyroscopic continua pipes conveying pulsating fluid parametric vibration nonlinear normal modes iterative approach

Ultra-thin Lam.nated metal Composites with Ultra-high Strength and Excellent Soft magnetic Properties

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Acta metallurgica Sinica(English Letters) 2020年第3期33卷 385-390页

作者： Le Zhang wei Wang Xiaofei Xiao m.Babar Shahzad Yiyin Shan Ke Yang Institute of metal Research Chinese Academy of SciencesShenyang 110016China School of materials Science and Engineering University of Science and Technology of ChinaHefei 230026China Key Laboratory of nuclear materials and Safety Assessm.nt Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China

Structural metallic materials with excellent functional perform.nce and lightweight features have always been the goal of material scientists’ *** this work,lam.nated metal composites of different thicknesses(less than 0.4 mm) composed of structural materials with great differences in deformation ability were successfully fabricated via a novel processing ***-high strength and excellent soft magnetic properties were combined perfectly in the ultra-thin and super-light lam.nated metal composite strips due to unique structural design and essential attributes of the initial *** results emphasize the significant potential application value of the ultra-thin lam.nated metal composites in the field of structural and functional integration.

关键词： Lam.nated metal composites Ultra-high strength Ultra-thin Soft magnetic property maraging steel

基于摆锤法的成熟期油菜角果炸荚因素试验分析

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农机化研究 2025年第4期47卷 180-185页

作者：李港张敏魏德欣江东农业农村部南京农业机械化研究所南京210014

为了降低油菜联合收割机拨禾轮拨禾过程对角果打击造成的炸荚损失,采用摆锤法模拟拨禾轮拨禾对油菜角果冲击过程,对影响拨禾过程中的炸荚因素进行测试分析,并对角果损伤变化形式及过程进行分析。试验结果表明:摆锤冲击速度3.5 m/s、夹... 详细信息

为了降低油菜联合收割机拨禾轮拨禾过程对角果打击造成的炸荚损失,采用摆锤法模拟拨禾轮拨禾对油菜角果冲击过程,对影响拨禾过程中的炸荚因素进行测试分析,并对角果损伤变化形式及过程进行分析。试验结果表明:摆锤冲击速度3.5 m/s、夹持果柄位置距连接点2 mm是区分角果抗打击炸荚的最优参数;油菜角果炸荚不仅与冲击速度、果柄夹持位置有关,而且与油菜品种、冲击件材料类型、角果受力面、含水率、角果在植株上的分布位置等都有关系;冲击速度不超过1.5 m/s时,角果损伤以角果果柄发生塑性变形为主;冲击速度为2.5~4.5 m/s时,角果损伤以果皮破裂分离、果柄弹性变形为主。研究结果可为油菜拨禾轮设计和工作参数选择提供参考。

关键词：油菜角果炸荚率冲击拨禾轮摆锤法

Signal processing for RIS-assisted millimeter-wave/terahertz comm.nications

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national Science Review 2023年第8期10卷 15-17页

作者： wei Wang wei Zhang Peng Cheng Laboratory School of Electrical Engineering and Telecomm.nications The University of New South Wales

InTRODUCTIOn The applications of millimeter-wave(mmWave, wavelength 1–10 mm) and terahertz(THz, wavelength 100 μm–1 mm) comm.nications are facing the challenges of severe free-space path loss and obstacle blockage. Aided by directional beamform.ng, the free-space path loss of mm Wave/THz comm.nications with a fixed effective aperture is potentially capable of reaching the same level as the lower frequency band, rendering obstacle blockage the biggest hindrance to mmWave/THz comm.nications.

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