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Journal of Environmental Sciences 2024年第2期136卷 486-497页

作者： Yingbo dong Huan Lu hai Lin School of Energy and Environmental Engineering University of Science and Technology BeijingBeijing 100083China Beijing Key Laboratory on Resource-oriented Treatment of Industrial Pollutants Beijing 100083China

The accumulation of coal gangue(CG)from coal mining is an important source of heavy metals(HMs)in *** spatial distribution and environment risk assessment are extremely important for the management and remediation of *** soil samples were collected from the high-sulfur CG site in northern China and analyzed for six *** results showed that the soil was heavily contaminated by Mn,Cr and Ni based on the Nemerow index,and posed seriously ecological risk depended on the geo-accumulation index,potential ecological risk index and risk assessment *** semi-variogram model and ordinary kriging interpolation accurately portrayed the spatial distribution of ***,Mn,and Cr were distributed by band diffusion,Ni was distributed by core,the distribution of Cu had obvious patchiness and Zn was more *** spatial autocorrelation indicated that all HMs had strong spatial *** BCR sequential extraction was employed to qualify the geochemical fractions of *** data indicated that Fe and Cr were dominated by residual fraction;Cu,Ni and Zn were dominated by reducible and oxidizable fractions;Mn was dominated by reducible and acid-extractable(25.38%-44.67%)*** correlation analysis showed that pH was the main control factor affecting the non-residue fractions of ***,acid production from high sulfur CG reduced soil pH by 2-3,which indirectly promoted the activity of ***,the conceptual model of HMs contamination at the CG site was proposed,which can be useful for the d.velopment of ecological remediation strategies.

关键词： High-sulfur coal gangue Soil contamination Heavy metals Spatial distribution Geochemical fractions Risk assessment

Bioleaching of vanadium from stone coal vanadium ore by Bacillus mucilaginosus:Influencing factors and mechanism

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International Journal of Minerals,Metallurgy and Materials 2024年第8期31卷 1828-1838页

作者： Yingbo dong Jinyu Zan hai Lin School of Energy and Environmental Engineering University of Science and Technology BeijingBeijing 100083China Beijing Key Laboratory on Resource-oriented Treatment of Industrial Pollutants Beijing 100083China

vanadium and its derivatives are used in various industries,including steel,metallurgy,pharmaceuticals,and aerospace *** China has massive reserves of stone coal resources,these resources have low ***,the effective extraction and recovery of metallic vanadium from stone coal is an important way to realize the efficient resource utilization of stone coal vanadium ***,Bacillus mucilaginosus was selected as the leaching *** vanadium leaching rate reached 35.5%after 20 d of bioleaching under optimal operating *** cumulative vanadium leaching rate in the contact group reached 35.5%,which was higher than that in the noncontact group(9.3%).The metabolites of ***,such as oxalic,tartaric,citric,and malic acids,dominated in bioleaching,accounting for 73.8%of the vanadium leaching ***,during leaching,the presence of stone coal stimulated the expression of carbonic anhydrase in bacterial cells,and enzyme activity increased by 1.335-1.905 *** activity positively promoted the production of metabolite organic acids,and total organic acid content increased by 39.31 mg·L^(-1),resulting in a reduction of 2.51 in the pH of the leaching system with stone *** effect favored the leaching of vanadium from stone *** force microscopy illustrated that bacterial leaching exacerbated corrosion on the surface of stone coal beyond 10 *** study provides a clear and promising strategy for exploring the bioleaching mechanism from the perspective of microbial enzyme activity and metabolites.

关键词： Bacillus mucilaginosus stone coal vanadium ore bioleaching carbonic anhydrase organic acids

Zeolite polymer membrane as protective interface for Mg battery

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Rare Metals 2024年第9期43卷 4636-4638页

作者： hai-Xia Wu Kai-Lu Guo College of Chemistry and Chemical Engineering Henan Key Laboratory of Function-Oriented Porous MaterialsLuoyang Normal UniversityLuoyang 471934China

Excessive electrolyte decomposition seriously determines the performance of high-voltage Mg batteries. In Nazar's work, the strategy using a zeolite polymer membrane as a protective interface was proposed to restrain the electrolyte decomposition. This strategy could boost Mg plating/stripping performance up to 6000 h in zeolite/Mg|zeolite/Mg symmetric cells and 91%capacity retention in zeolite/Mg||Mo_(3)S_(4)battery after 200 *** storage d.vices have been intensively explored because of their important roles in our daily lives [1d3].

关键词： zeolite interface electrolyte

Fatigue-resistant Hydrogels

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Chemical Research in Chinese Universities 2024年第1期40卷 64-77页

作者： LI Luofei LEI hai CAO Yi Collaborative Innovation Center of Advanced Microstructures National Laboratory of Solid State MicrostructureDepartment of PhysicsNanjing UniversityNanjing 210093P.R.China department of Physics Zhejiang UniversityHangzhou 310027P.R.China

Hydrogels have been extensively studied for applications in various fields, such as tissue engineering and soft robotics, as determined by their mechanical properties. The mechanical design of hydrogels typically focuses on the modulus, toughness, and deformability. These characteristics play important roles and make great achievements for hydrogel use. In recent years, a growing body of research has concentrated on the fatigue property of hydrogels, which determines their resistance to crack propagation in the networks during cyclic mechanical loads for applications. However, knowledge of hydrogel fatigue behavior remains notably deficient. Here, we present a brief overview of the fatigue behavior of hydrogels, encompassing the general experimental methods to measure the fatigue property and fundamental theoretical calculation models. Then, we highlight multiple strategies to enhance the fatigue resistance of hydrogels. Finally, we present our perspectives on fatigue-resistant hydrogels, outstanding challenges and potential directions for future research.

关键词： Hydrogel Fatigue-resistant Fracture

design optimization of a hexapod.vibration isolation system for electro-optical payload

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Chinese Journal of Aeronautics 2024年第2期37卷 330-342页

作者： Jing LI Weipeng LI Xiaoyan ZHANG hai HUANG School of Astronautics Beihang UniversityBeijing 100191China

The electro-optical payloads on mobile platforms generally suffer undesirable vibrations generated by maneuvers and *** vibrations are in six degrees of freedom and cause line-of-sight jitters,resulting in image blurring and loss of tracking *** this paper,a Hexapod.vibration Isolation System(HvIS)is proposed and optimized to solve this *** optimization aims to centralize and minimize the natural frequencies of HvIS,for expanding the vibration isolation bandwidth and improving the vibration isolation in the higher frequency *** that the design space for HvIS is limited and interfered with the frames of the mobile platform,a non-collision algorithm is proposed and applied in the optimization to obtain the feasible optimal *** optimization result shows that the natural frequency bandwidth has been reduced by 42.9%,and the maximum natural frequency is reduced by 30.2%.The prototypes of initial and optimal designs are manufactured and *** simulated and experimental results demonstrate the validity of the optimization,and the optimal design provides a maximum of 15 dB more isolation in rotation direction than the initial design.

关键词： Electro-optical payload vibrations Isolation system Hexapod Optimization Non-collision design

Layer Hall effect induced by hidden Berry curvature in antiferromagnetic insulators

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National Science Review 2024年第2期11卷 15-23页

作者： Rui Chen hai-Peng Sun Mingqiang Gu Chun-Bo Hua Qihang Liu hai-Zhou Lu X.C.Xie Shenzhen Institute for Quantum Science and Engineering and department of Physics Southern University of Science and Technology(SUSTech) International Quantum Academy Institute for Theoretical Physics and Astrophysics University of Würzburg School of Electronic and Information Engineering Hubei University of Science and Technology Guangdong Provincial Key Laboratory of Computational Science and Material design Southern University of Science and Technology Shenzhen Key Laboratory of Quantum Science and Engineering International Center for Quantum Materials School of PhysicsPeking University Collaborative Innovation Center of Quantum Matter CAS Center for Excellence in Topological Quantum Computation University of Chinese Academy of Sciences

The layer Hall effect describes electrons spontaneously deflected to opposite sides at different layers, which has been experimentally reported in the MnBi2Te4thin films under perpendicular electric fields. Here, we reveal a universal origin of the layer Hall effect in terms of the so-called hidden Berry curvature, as well as material design principles. Hence, it gives rise to zero Berry curvature in momentum space but non-zero layer-locked hidden Berry curvature in real space. We show that, compared to that of a trivial insulator, the layer Hall effect is significantly enhanced in antiferromagnetic topological insulators. Our universal picture provides a paradigm for revealing the hidden physics as a result of the interplay between the global and local symmetries, and can be generalized in various scenarios.

关键词： layerHall effect hidden Berry curvature antiferromagnetic insulator axion insulator, quantum transport

A Rendezvous Mission to the Second Earth Trojan Asteroid 2020 XL_5 with Low-Thrust Multi-Gravity Assist Techniques

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Research in Astronomy and Astrophysics 2024年第1期24卷 245-264页

作者： Shi-hai Yang Bo Xu Xin Li School of Aeronautics and Astronautics Sun Yat-sen UniversityShenzhen 518107China

As the second of Earth's Trojan asteroids, 2020 XL_(5) is worthy of rendezvous and even sample return missions in many aspects. In this paper, a rendezvous mission to Earth's second Trojan asteroid 2020 XL_(5) is ***, due to its high inclination and large eccentricity, direct impulsive transfer requires large amounts of fuel consumption. To address this challenge, we explore the benefits of electric propulsion and multi-gravity assist techniques for interplanetary missions. These two techniques are integrated in this mission design. The design of a low-thrust gravity-assist(LTGA) trajectory in multi-body dynamics is thoroughly investigated,which is a complex process. A comprehensive framework including three steps is presented here for optimization of LTGA trajectories in multi-body dynamics. The rendezvous mission to 2020 XL_(5) is designed with this three-step approach. The most effective transfer sequence among the outcomes involves Earth–venus–Earth–venus-2020 XL_(5). Numerical results indicate that the combination of electric propulsion and multi-gravity assists can greatly reduce the fuel consumption, with fuel consumption of 9.03%, making it a highly favorable choice for this rendezvous mission.

关键词： minor planets asteroids:general celestial mechanics Planetary Systems

The multi-impurity system in CdSe nanoplatelets:electronic structure and thermodynamic properties

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Communications in Theoretical Physics 2024年第3期76卷 165-173页

作者： d A Baghdasaryan v A Harutynyan E M Kazaryan H A Sarkisyan Russian-Armenian University H Emin 1230051YerevanArmenia Institute of Applied Problems of Physics 25 Nersisyan St0014YerevanArmenia

This paper theoretically studies the impurity states and the effects of impurity concentration and configuration on the optical,electrical,and statistical properties of CdSe nanoplatelets(NPLs).An image charge-based model of electron-impurity interaction is *** charge-carrier energy spectra and corresponding wave functions depending on the impurity number and configuration are *** electron binding energies are calculated for different NPL *** is shown that the image charge-based interaction potential that arises due to the dielectric constants mismatch is much stronger than the interaction potential that does not take such a mismatch into ***,it is demonstrated that the binding energies are increasing with the number of *** calculate the canonical partition function using the energy levels of the electron,which in turn is used to obtain the mean energy,heat capacity,and entropy of the non-interacting electron *** thermodynamic properties of the non-interacting electron gas that depend on the geometric parameters of the NPL,impurity number,configuration,and temperature are studied.

关键词： nanoplateletes thermodynamic properties impurity states

Ion heat transport in electron cyclotron resonance heated L-mode plasma on the T-10 tokamak

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Plasma Science and Technology 2024年第4期26卷 52-60页

作者： v.A.KRUPIN M.R.NURGALIEv A.R.NEMETS I.A.ZEMTSOv S.d.SUNTSOv T.B.MYALTON d.S.SERGEEv N.A.SOLOvEv d.v.SARYCHEv d.v.RYJAKOv S.N.TUGARINOv N.N.NAUMENKO National Research Centre“Kurchatov Institute” Moscow 123182Russia Bauman Moscow State Technical University Moscow 105005Russia Institution“Project Center ITER” Moscow 123098Russia JSC“SOLAR” Minsk 220034Belarus

Anomalous ion heat transport is analyzed in the T-10 tokamak plasma heated with electron cyclotron resonance heating(ECRH) in second-harmonic extra-ordinary mode. Predictive modeling with empirical scaling for Ohmical heat conductivity shows that in ECRH plasmas the calculated ion temperature could be overestimated, so an increase of anomalous ion heat transport is required. To study this effect two scans are presented: over the EC resonance position and over the ECRH power. The EC resonance position varies from the high-field side to the low-field side by variation of the toroidal magnetic field. The scan over the heating power is presented with on-axis and mixed ECRH regimes. discharges with high anomalous ion heat transport are obtained in all considered regimes. In these discharges the power balance ion heat conductivity exceeds the neoclassical level by up to 10 times. The high ion heat transport regimes are distinguished by three parameters: the ratio Te/Ti, the normalized electron density gradient R/■, and the ion–ion collisionality νii~*. The combination of high Te/Ti, high νii~*, and R/■=6-10 results in values of normalized anomalous ion heat fluxes up to 10 times higher than in the low transport scenario.

关键词： tokamak L-mode electron cyclotron resonance heating ion heat transport