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Unraveling electrolyte solvation architectures for high-performance lithium-ion batteries

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Science China(Technological Sciences) 2024年第3期67卷 958-964页

作者： YANG MengHao shi zhe HE ZhiYuan WANG Dan School of Materials Science and Engineering Tongji UniversityShanghai 201804China Department of Nuclear Science and Engineering Massachusetts Institute of Technology CambridgeMassachuseis 02139USA School of Materials Science and Engineering Beijing Institute of TechnologyBeijing 100081China

The design of advanced electrolytes hinges critically on a comprehensive comprehension of lithium-ion migration mechanisms within these electrochemical systems. Fluorination generally improves the stability and reduces the reactivity of organic compounds, making them potentially suitable for use in harsh conditions such as those found in a battery electrolyte. However,the specific properties, such as the solvation power, diffusivity, ion mobility, and so forth, would depend on the exact nature and extent of the fluorination. In this work, we introduce a theoretical framework designed to facilitate the autonomous creation of electrolyte molecular structures and craft methodologies to compute transport coefficients, providing a physical interpretation of fluoride systems. Taking fluorinated-1,2-diethoxyethanes as electrolyte solvents, we present and analyze the relationship between the electronic properties and atomic structures, and further correlate these properties to the transport coefficients, resulting in a good alignment with the experimental diffusion behaviors and Li-solvation structures. The insights derived from this research contribute to the methodological basis for high-throughput evaluation of prospective electrolyte systems, and consequently, propose strategic directions for the improvement of electrochemical cycle characteristics. This comprehensive exploration of the transport mechanisms enhances our understanding, offering avenues for further advancements in the field of lithium-ion battery technology.

关键词： Unraveling electrolyte solvation architectures for high-performance lithium-ion batteries

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Steel ladle exchange models during steelmaking and continuous casting process

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Journal of Iron and Steel Research International 2017年第6期24卷 617-624页

作者： Bang-fu Huang Nai-yuanTian zhe shi Zhi-wei Ma Faculty of Metallurgical and Energy Engineering Kunming University of Science and Technology Kunming 650093 YunnanChina Clean Metallurgy Key Laboratory of Complex Iron Resources Kunming 650093 Yunnan China School of Metallurgical and Ecological Engineering University of Science and Technology Beijing Beijing 100083 China

The models and influencing factors of steel ladles exchange during the steelmaking and continuous casting process of H steel plant were investigated. Based on analysis of the operation process and turnover time of steel ladles, relationship models for the turnover number, turnover rate, continuous casting number, number of ladles with additional turnover, and number of ladles without additional turnover were built. The turnover rules of steel ladles for one basic oxygen furnace （BOF） matching one continuous caster （CC） and two BOFs matching two CCs modes were simulated by using a Gantt chart. The models of steel ladle exchange were proposed for casting of a single CC and overlapping casting of two CCs. By analyzing the influencing factors, the following conclusions were drawn. The exchange ladle should not have the task of transporting liquid ste^l in the CC that stops casting earli- er. The end time of the empty ladle in the CC that stops casting earlier should be earlier than the start time of the full ladle in the CC that stops casting later. After evaluating the factors influencing the start casting time, turnover cycle, casting time, continuous casting number, and overlapping time, a prioritization scheme of steel ladle exchange was proposed based on the steel grade. First, the turn- over cycle and single heat casting time were determined; based on these, a reasonable ladle turnover number was calculated. Second, the turnover number and continuous casting number were optimized for maximizing the number of ladles without additional turnover. Lastly, to reduce the casting number during the overlapping time to be lower than the turnover number, the overlapping time was shortened.

关键词： SteelmakingContinuous castingSteel ladleExchange modelTurnover optimizationProduction scheduling

Multi-objective optimization of a flow straightener in a large capacity firefighting water cannon

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Journal of Hydrodynamics 2019年第1期31卷 137-144页

作者： Qing-jiang Xiang Lin Xue Kwang-Yong Kim zhe-fu shi National Research Centre of Pumps Jiangsu UniversityZhenjiang 212013China Department of Mechanical Engineering Inha UniversityIncheonKorea Shanghai Fire Research Institute of Ministry of Emergency Management Shanghai 200032China

In the present study,a multi-objective optimization of a flow straightener in a firefighting water cannon is performed by using the surrogate modeling and a hybrid multi-objective genetic algorithm to increase the jet range of the water *** on analysis using the three-dimensional Reynolds-averaged Navier-Stokes equations,the optimization is carried with a surrogate model and the radial basis neural *** geometric design variables,i.e.,the lengt扎 the thickness of the blade,and the radius of the outer pipe of the flow straightener,are selected for the *** pressure drop through the water can non and the area-averaged turbulent kinetic energy at the outlet of the water cannon,which are closely related to the jet range of the water cannon,are selected as the objective functions to be *** design space is determined through a parametric study,and the Latin hypercube sampling method is used to select the design points in the design *** Pareto-optimal solutions are obtained through the *** representative Pareto-optimal solutions are selected to study the trade-off between two objectives.

关键词： Firefighting water cannon multi-objective optimization surrogate model turbulence kinetic energy hydraulic loss

Two-dimensional selenium and its composites for device applications

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Nano Research 2022年第1期15卷 104-122页

作者： zhe shi Hongqiao Zhang Karim Khan Rui Cao Kaikai Xu Han Zhang School of Physics&New Energy Xuzhou University of TechnologyXuzhou 221018China Shenzhen Engineering Laboratory of phosphorene and Optoelectronics Collaborative Innovation Center for Optoelectronic Science and Technology and Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong ProvinceShenzhen UniversityShenzhen 518060China State Key Laboratory of Electronic Thin Films and Integrated Devices University of Electronic Science and Technology of ChinaChengdu 610054China

Two-dimensional(2D)selenium was synthesized successfully in *** advanced properties,including size-dependent bandgap,excellent environmental robustness,strong photoluminescence effect,anisotropic thermal conductivity,and high photoconductivity,render it and selenium-based composites a promising candidate for various device *** include batteries,modulators,photodetectors,and photothermal effects in medical ***,compared to other commonly used 2D materials,such as graphene,transition metal dichalcogenides,and black phosphorus,2D Se is much less *** by the need to overcome this lack of knowledge,this article focuses on recent progress and elucidates the crystal structure,synthesis methods,physical properties,applications,challenges,and prospects of 2D Se nanoflakes.

关键词： two-dimensional materials selenium batteries photodetectors photothermal effect

A COUNTER PROPAGATING WAVE STATE WITH A PERIODICALLY HORIZONTAL MOTION OF DEFECTS

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Journal of Hydrodynamics 2008年第5期20卷 567-573页

作者： NING Li-zhong QI Xin YUAN zhe shi Feng Institute of Hydraulic Engineering Xi＇an University of Technology Xi＇an 710048 China

Convection in a horizontal fluid layer heated from below is one of models for studying patterns of convection in binary fluid mixtures and has been extensively studied. In this article, the convection structures in a rectangular cell were investigated for the aspect-ratio Г= 12 and the separation ratio ψ = -0.47. Simulations were preformed by solving the hydrodynamic equations using the SIMPLE method. A Counter Propagating Wave （CPW） state was found in binary fluid convection with a periodically horizontal motion of defects, and the pattern dynamics was further discuss.

关键词： Counter Propagating Wave (CPW) defect convection pattern dynamics

Electrochemical investigation of the anode processes in LiF-NdF3 melt with low oxygen content

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International Journal of Minerals,Metallurgy and Materials 2021年第3期28卷 398-403页

作者： Chen-ming Fan shi-zhe Liu Jing-jiu Gu shi-you Guan Jin-hua Zhao Bing Li School of Mechanical and Power Engineering East China University of Science and TechnologyShanghai 200237China Institute for Sustainable Energy College of SciencesShanghai UniversityShanghai 200444China Collaborative Innovation Center of Clean Energy Longyan UniversityLongyan 364012China

The oxidation of oxygen ions and the generation of an anode effect at a low oxygen content of 150 mg/kg were discussed in this *** voltammetry and square-wave voltammetry tests were conducted to explore the anodic processes of LiF-NdF_(3)melt after a lengthy period of pre-electrolysis purification at 1000℃(during which the oxygen content reduced from 413 to 150 mg/kg).The oxidation process of oxygen ions was found to have two stages:oxidation product adsorption and CO/CO_(2)gas *** adsorption stage was controlled by diffusion,whereas the gas evolution was controlled by the electrochemical *** comparison with oxygen content of 413 mg/kg,the decrease in the amplitude of the current at low oxygen content of 150 mg/kg was much gentler during the forward scanning process when the anode effect ***-ion oxidation peaks that occurred at about 4.2 V ***/Li+could be clearly observed in the reverse scanning processes,in which fluorine ions were oxidized and perfluorocarbons were produced,which resulted in an anode effect.

关键词： LiF-NdF_(3)melt neodymium electrowinning low oxygen content anode processes

Optical forces exerted on a graphene-coated dielectric particle by a focused Gaussian beam

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Photonics Research 2016年第2期4卷 65-69页

作者： Yang Yang zhe shi Jiafang Li Zhi-Yuan Li Laboratory of Optical Physics Institute of Physics Chinese Academy of Sciences Key Laboratory of Micro-Nano Measurement-Manipulation and Physics (Ministry of Education) Beihang University

In this paper, we derive the analytical expression for the multipole expansion coefficients of scattering and interior fields of a graphene-coated dielectric particle under the illumination of an arbitrary optical beam. By using this arbitrary beam theory, we systematically investigate the optical forces exerted on the graphene-coated particle by a focused Gaussian beam. Via tuning the chemical potential of the graphene, the optical force spectra could be modulated accordingly at resonant excitation. The hybridized whispering gallery mode of the electromagnetic field inside the graphene-coated polystyrene particle is more intensively localized than the pure polystyrene particle, which leads to a weakened morphology-dependent resonance in the optical forces. These investigations could open new perspectives for dynamic engineering of optical manipulations in optical tweezers applications.

关键词： Optical forces exerted on a graphene-coated dielectric particle by a focused Gaussian beam

Machine learning for deep elastic strain engineering of semiconductor electronic band structure and effective mass

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npj Computational Materials 2021年第1期7卷 694-703页

作者： Evgenii Tsymbalov zhe shi Ming Dao Subra Suresh Ju Li Alexander Shapeev Skolkovo Institute of Science and Technology MoscowRussia Department of Materials Science and Engineering and Department of Nuclear Science and Engineering Massachusetts Institute of TechnologyCambridgeMAUSA Nanyang Technological University SingaporeRepublic of Singapore

The controlled introduction of elastic strains is an appealing strategy for modulating the physical properties of semiconductor *** the recent discovery of large elastic deformation in nanoscale specimens as diverse as silicon and diamond,employing this strategy to improve device performance necessitates first-principles computations of the fundamental electronic band structure and target figures-of-merit,through the design of an optimal straining *** simulations,however,call for approaches that combine deep learning algorithms and physics of deformation with band structure calculations to custom-design electronic and optical *** by this challenge,we present here details of a machine learning framework involving convolutional neural networks to represent the topology and curvature of band structures in *** calculations enable us to identify ways in which the physical properties can be altered through“deep”elastic strain engineering up to a large fraction of the ideal *** capable of active learning and informed by the underlying physics were presented here for predicting the bandgap and the band *** training a surrogate model with ab initio computational data,our method can identify the most efficient strain energy pathway to realize physical property *** power of this method is further demonstrated with results from the prediction of strain states that influence the effective electron *** illustrate the applications of the method with specific results for diamonds,although the general deep learning technique presented here is potentially useful for optimizing the physical properties of a wide variety of semiconductor materials。

关键词： strain deformation electronic

Numerical optimization of gourd-shaped surface texture and experiment of tribological performance

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Journal of Central South University 2017年第12期24卷 2773-2782页

作者： CHEN Ping LI Jun-ling shi zhe XIANG Xin School of Mechanical Engineering University of Science and Technology Beijing Beijing 100083 China

A numerical optimization approach based on the finite element(FE) simulation was used to design the optimum irregular gourd-shaped pattern parameters for generating the highest hydrodynamic pressure. Then the optimum parameters of the gourd-shaped surface texture were determined and the textures were processed on the stainless steel surface by the laser technology. The tribological performance of gourd-shaped surface texture was analyzed using the type of UMT2 tester, and compared with that of the regular circle surface texture and none-texture surface by considering the effect of sliding speeds and applied loads on the tribological performance. The results show that the compound factor n, the diameter ratio Dr and the texture depth Hd are more significant parameters and the optimum values are 0.618, 2.0 and 4 μm, respectively. In addition, irregular gourd-shaped surface texture with optimum parameters is the most effective in the friction reduction among the patterns investigated under different speeds and applied loads in this work. Moreover, better coordination and combination effect can be obtained by gourd-shaped surface texture. The main reason responsible for the results is the irregular symmetric nature of the gourd-shaped texture along the direction of lubricants flowing which can generate the higher fluid dynamic pressure.

关键词： gourd-shaped texture irregular symmetric tribological performance numerical and experimental