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Phase-field lattice-Boltzmann study on fully coupled thermal-solute-convection dendrite growth of Al-Cu alloy

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China Foundry 2024年第2期21卷 125-136页

作者： Yin-qi Qiu meng-wu Wu Xun-peng Qin Shou-mei xiong Hubei Key Laboratory of Advanced Technology for Automotive Components Wuhan University of TechnologyWuhan 430070China Hubei Longzhong Laboratory Xiangyang 441000HubeiChina School of Materials Science and Engineering Tsinghua UniversityBeijing 100084China

Dendrite growth is a complex liquid-solid phase transition process involving multiple physical factors.A phase-field lattice-Boltzmann method was developed to simulate the two-and three-dimension dendrite growth of Al-Cu *** effect of fully coupled thermal-solute-convection interaction on the dendrite growth was investigated by incorporating a parallel-adaptive mesh refinement algorithm into the numerical *** accurately reproducing the latent heat release,solute diffusion and convective transport behaviors at the liquidsolid interface,the interaction mechanism among thermal-solute-convection transport as well as their coupling effects on the dendrite growth dynamics were *** simulation results show that the release of latent heat slows down the dendrite growth rate,and both natural and forced convection disrupt the symmetrical growth of *** combination makes the growth of dendrites more complex,capturing important physical aspects such as recalescence,dendrite tip splitting,dendrite tilting,dendrite remelting,and solute plume in the simulation *** on the robustness and powerful ability of the numerical model,the formation mechanisms of these physical aspects were revealed.

关键词： simulation phase field dendrite growth thermal-solute-convection interaction

Research status and perspectives of MXene-based materials for aqueous zinc-ion batteries

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Rare Metals 2024年第5期43卷 1867-1885页

作者： Xiao-Yu Wang Qi-Hang Yang Xin-Yan meng meng-meng Zhen Zhen-Zhong Hu Bo-xiong Shen School of Energy and Environmental Engineering Hebei University of TechnologyTianjin 300071China

Aqueous zinc-ion batteries(AZIBs)as green battery systems have attracted widespread attention in large-scale electrochemical energy storage devices,owing to their high safety,abundant Zn materials,high theoretica specific capacity and low redox *** there are some thorny issues in AZIBs that hinder their practical application,such as low intrinsic electron conductivity,slow ion migration kinetics,zinc dendrites and side ***-based materials with superior conductivity,large polar surface and abundant active sites can simultaneously serve as cathode materials,electrolyte additive and protection layer of anode to regulate redox reactions of *** various materials have been used to improve electrochemical performances of AZIBs there is a lack of in-depth discussion on the regulation mechanism of MXene-based materials for *** this review,we elaborate the research progress of MXenebased materials in AZIBs,including their application in cathode materials and inhibition of zinc *** the future prospects and development directions of MXenebased materials that may improve performance of AZIBs are prospected.

关键词： MXene Aqueous zinc-ion batteries Composite materials Zinc dendrites

Advances in environmental DNA monitoring:standardization,automation,and emerging technologies in aquatic ecosystems

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Science China(Life Sciences) 2024年第7期67卷 1368-1384页

作者： Suxiang Lu Honghui Zeng Fan xiong meng Yao Shunping He State Key Laboratory of Freshwater Ecology and Biotechnology Institute of HydrobiologyChinese Academy of SciencesWuhan 430072China Institute of Ecology College of Urban and Environmental SciencesPeking UniversityBeijing 100871China School of Life Sciences Peking UniversityBeijing 100871China Institute of Deep Sea Science and Engineering Chinese Academy of SciencesSanyaChina Center for Excellence in Animal Evolution and Genetics Chinese Academy of SciencesKunmingChina

Environmental DNA(eDNA)monitoring,a rapidly advancing technique for assessing biodiversity and ecosystem health,offers a noninvasive approach for detecting and quantifying species from various environmental *** this review,a comprehensive overview of current eDNA collection and detection technologies is provided,emphasizing the necessity for standardization and automation in aquatic ecological ***,the intricacies of water bodies,from streams to the deep sea,and the associated challenges they pose for eDNA capture and analysis are *** paper delineates three primary eDNA survey methods,namely,bringing back water,bringing back filters,and bringing back data,each with specific advantages and constraints in terms of labor,transport,and data ***,innovations in eDNA sampling equipment,including autonomous drones,subsurface samplers,and in-situ filtration devices,and their applications in monitoring diverse taxa are ***,recent advancements in species-specific detection and eDNA metabarcoding are addressed,highlighting the integration of novel techniques such as CRISPR-Cas and nanopore sequencing that enable precise and rapid detection of *** implications of environmental RNA and epigenetic modifications are considered for future applications in providing nuanced ecological ***,the review stresses the critical role of standardization and automation in enhancing data consistency and comparability for robust long-term *** propose that the amalgamation of these technologies represents a paradigm shift in ecological monitoring,aligning with the urgent call for biodiversity conservation and sustainable management of aquatic ecosystems.

关键词： eDNA methodology sampler environment biomonitoring ecogenomic sensors ocean observation instrument

Environment-adaptive phase-separation-porous fluorofilm for highperformance passive radiation cooling

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Nano Research 2024年第6期17卷 5636-5644页

作者： Weiming tang Yong Li Xue meng Shutao Wang Ziguang Zhao School of Future Technology University of Chinese Academy of SciencesBeijing 100049China CAS Key Laboratory of Bio-inspired Materials and Interfacial Science Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijing 100190China CAS Key Laboratory of Cryogenics Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijing 100190China

Passive radiative cooling is widely recognized as an environmentally sustainable method for achieving significant cooling ***,the mechanical properties and environmental adaptability of current radiative cooling materials are not sufficient to maintain high cooling performance in external *** we reported an environment-adaptive phase-separation-porous fluorofilm for high-performance passive radiation *** to the homogenous fluoro-porous network with limited scattering efficiencies,we modulated the porous structure of the fluorofilm to achieve a strong emissivity of 95.2%(8-13μm)and a high reflectivity of 97.1%(0.3-2.5μm).The fluorofilm demonstrates a temperature drop of 10.5°C and an average cooling power of 81 W·m^(−2)under a sunlight power of 770 W·m^(−2).The high mechanical performance and environmental adaptability of fluorofilms are also *** its significant radiative cooling capability and robust environmental adaptability,the fluorofilm is expected to have a promising future in radiative temperature regulation.

关键词： fluorofilm passive radiation cooling porous optimization thermal regulation

Fully polarized Compton scattering in plane waves and its polarization transfer

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Matter and Radiation at Extremes 2024年第3期9卷 45-56页

作者： Suo tang Yu Xin meng Wen Mamat Ali Bake Baisong Xie College of Physics and Optoelectronic Engineering Ocean University of ChinaQingdaoShandong 266100China Department of Physics Hubei UniversityWuhan 430062China Xinjiang Key Laboratory of Solid State Physics and Devices School of Physics Science and TechnologyXinjiang UniversityUrumqi 830017China Key Laboratory of Beam Technology of the Ministry of Education and College of Nuclear Science and TechnologyBeijing Normal UniversityBeijing 100875China

Fully polarized Compton scattering from a beam of spin-polarized electrons is investigated in plane-wave backgrounds in a broad intensity region from the perturbative to the nonperturbative *** the perturbative regime,polarized linear Compton scattering is considered for investigating polarization transfer from a single laser photon to a scattered photon,and in the high-intensity region,the polarized locally monochromatic approximation and locally constant field approximation are established and are employed to study polarization transfer from an incoming electron to a scattered *** numerical results suggest an appreciable improvement of about 10%in the scattering probability in the intermediate-intensity region if the electron’s longitudinal spin is parallel to the laser *** longitudinal spin of the incoming electron can be transferred to the scattered photon with an efficiency that increases with laser intensity and collisional *** collision between an optical laser with frequency1 eV and a 10 GeV electron,this polarization transfer efficiency can increase from about 20%in the perturbative regime to about 50%in the nonperturbative regime for scattered photons with relatively high energy.

关键词： polarized scattered transfer

Geomorphology-oriented theoretical framework and construction method for value-added DEM

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Journal of Geographical Sciences 2024年第1期34卷 165-184页

作者： ZHANG Haiping tang Guoan xiong Liyang YANG Xin LI Fayuan Key Laboratory of Virtual Geographic Environment Ministry of EducationNanjing Normal UniversityNanjing 210023China School of Geography Nanjing Normal UniversityNanjing 210023China Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application Nanjing 210023China

Digital elevation model(DEM)plays a fundamental role in the study of the earth system by expressing surface configuration,understanding surface process,and revealing surface *** is widely used in analysis and modeling in the field of ***,traditional DEM has the defect of single attribute,which is difficult to support the research in earth system science oriented to geoscience process and mechanism ***,realizing the value-added data model on the basis of traditional DEM is necessary to serve digital elevation modeling and terrain analysis under the background of a new geomorphology research paradigm and earth observation technology.A theoretical framework for value-added DEM that mainly includes concept,connotation,content,and categories,is constructed in this *** relationship between different types of value-added DEMs as well as the research significance and application category of this theoretical framework are also *** following are different methods of value-added DEMs:(1)value-added methods of DEM space and time dimensions that emphasize the integration of the ground and underground as well as coupling of time and space,(2)attribute-based value-added methods composed of material(including underground,surface,and ground)and morphological properties,and(3)value-added methods of features and physical elements that consider geographical objects and landform features formed by natural processes and artificial *** digital terrace,slope,and watershed models are used as examples to illustrate application scenarios of the three kinds of value-added *** study aims to improve expression methods of DEMs under the background of new surveying and mapping technologies by adding value to the DEM at three levels of dimensions,attributes,and elements as well as support knowledge-driven digital geomorphological analysis in the era of big data.

关键词： spatial data model value-added DEM digital terrain analysis geomorphological ontology geomorphology

The Impact of New Regulations on Prevention and Control of E-Cigarettes on Adolescents in Middle Schools—A City in China,2022–2023

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China CDC weekly 2024年第14期6卷 289-293页

作者： meng Lyu Wenlong Lu Lanhua Zou Jingfan xiong Jie Yang Tobacco Control Office Chinese Center for Disease Control and PreventionBeijingChina Shenzhen Center for Chronic Disease Control Shenzhen CityGuangdong ProvinceChina

What is already known about this topic?To protect the health of young people from the harmful impacts of electronic cigarettes(e-cigarettes),China has enacted various policies and regulations since *** of October 1,2022,the Electronic Cigarette Management Measures were put into *** prohibited the sale of flavored e-cigarettes,permitting only those of plain tobacco flavor to be *** is added by this report?The illegal market for flavored e-cigarettes,often disguised as milk tea cups,cola cans,and violent bear images,continues to *** is an increased need to bolster support for the prohibition of flavored e-cigarettes and enhance public awareness of associated *** are the implications for public health practice?To advance the health of China’s youth,it is crucial to improve the implementation and understanding of ecigarette policies and guidelines.

关键词： Middle Impact plain

Predicting submerged vegetation drag with a machine learning-based method

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Journal of Hydrodynamics 2024年第3期36卷 534-545页

作者： meng-yang Liu Hong-wu tang Sai-yu Yuan Jing Yan College of Water Conservancy and Hydropower Engineering Hohai UniversityNanjing210098China Key Laboratory of Hydrologic-Cycle and Hydrodynamic-System of Ministry of Water Resources Hohai UniversityNanjing210098China

Accurate estimation of the drag forces generated by vegetation stems is crucial for the comprehensive assessment of the impact of aquatic vegetation on hydrodynamic processes in aquatic *** coupling relationship between vegetation layer flow velocity and vegetation drag makes precise prediction of submerged vegetation drag forces particularly *** present study utilized published data on submerged vegetation drag force measurements and employed a genetic programming(GP)algorithm,a machine learning technique,to establish the connection between submerged vegetation drag forces and flow and vegetation *** using the bulk velocity,U,as the reference velocity scale to define the drag coefficient,C_(d),and stem Reynolds number,the GP runs revealed that the drag coefficient of submerged vegetation is related to submergence ratio(H^(*)),aspect ratio(d^(*)),blockage ratio(ψ^(*)),and vegetation density(λ).The relation between vegetation stem drag forces and flow velocity is implicitly embedded in the definition of C_(d).Comparisons with experimental drag force measurements indicate that using the bulk velocity as the reference velocity,as opposed to using the vegetation layer average velocity,U_(v),eliminates the need for complex iterative processes to estimate U_(v)and avoids introducing additional errors associated with U_(v)*** approach significantly enhances the model’s predictive capabilities and results in a simpler and more user-friendly formula expression.

关键词： Drag coefficient genetic programming algorithm submerged vegetation flow resistance cylinder array

In situ direct reprogramming of astrocytes to neurons via polypyrimidine tract-binding protein 1 knockdown in a mouse model of ischemic stroke

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Neural Regeneration Research 2024年第10期19卷 2240-2248页

作者： meng Yuan Yao tang Tianwen Huang Lining Ke En Huang Key Laboratory of Brain Aging and Neurodegenerative Diseases of Fujian Province Fujian Medical UniversityFuzhouFujian ProvinceChina Department of Human Anatomy School of Basic Medical SciencesFujian Medical UniversityFuzhouFujian ProvinceChina Scientific Research Center School of Basic Medical SciencesFujian Medical UniversityFuzhouFujian ProvinceChina Department of Neurology Fujian Medical University Union HospitalFuzhouFujian ProvinceChina Fujian Key Laboratory of Vascular Aging Fujian Medical UniversityFuzhouFujian ProvinceChina

In situ direct reprogramming technology can directly convert endogenous glial cells into functional neurons in vivo for central nervous system repair. Polypyrimidine tract-binding protein 1(PTB) knockdown has been shown to reprogram astrocytes to functional neurons in situ. In this study, we used AAV-PHP.e B-GFAP-sh PTB to knockdown PTB in a mouse model of ischemic stroke induced by endothelin-1, and investigated the effects of GFAP-sh PTB-mediated direct reprogramming to neurons. Our results showed that in the mouse model of ischemic stroke, PTB knockdown effectively reprogrammed GFAP-positive cells to neurons in ischemic foci, restored neural tissue structure, reduced inflammatory response, and improved behavioral function. These findings validate the effectiveness of in situ transdifferentiation of astrocytes, and suggest that the approach may be a promising strategy for stroke treatment.

关键词： astrocyte in situ direct reprogramming ischemic stroke miR-30 based shRNA neuron polypyrimidine tract-binding protein 1 transdifferentiation