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Thermodynamic theory of flotation for a complex multiphase solid -liquid system and high-entropy flotation

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International Journal of Minerals,Metallurgy and Materials 2024年第6期31卷 1177-1197页

作者： Shuming wen State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization Faculty of Land Resource EngineeringKunming University of Science and TechnologyKunming 650093China

The flotation of complex solid–liquid multiphase systems involve interactions among multiple components,the core problem facing flotation ***,the combined use of multicomponent flotation reagents to improve mineral flotation has become an important issue in studies on the efficient use of refractory mineral ***,studying the flotation of complex solid–liquid systems is extremely difficult,and no systematic theory has been developed to *** addition,the physical mechanism associated with combining reagents to improve the flotation effect has not been unified,which limits the development of flotation theory and the progress of flotation *** this study,we applied theoretical thermodynamics to a solid–liquid flotation system and used changes in the entropy and Gibbs free energy of the reagents adsorbed on the mineral surface to establish thermodynamic equilibrium equations that de-scribe interactions among various material components while also introducing adsorption equilibrium constants for the flotation reagents adsorbed on the mineral *** homogenization effect on the mineral surface in pulp solution was determined using the chemical potentials of the material components of the various mineral surfaces required to maintain *** flotation effect can be improved through synergy among multicomponent flotation reagents;its physical essence is the thermodynamic law that as the number of compon-ents of flotation reagents on the mineral surface increases,the surface adsorption entropy change increases,and the Gibbs free energy change of adsorption *** to the results obtained using flotation thermodynamics theory,we established high-entropy flotation theory and a technical method in which increasing the types of flotation reagents adsorbed on the mineral surface,increasing the adsorption entropy change of the flotation reagents,decreasing the Gibbs free energy change,and improving the adsorption efficiency

关键词： multicomponent flotation reagent adsorption entropy change equations of thermodynamic equilibrium adsorption equilibri-um constant high-entropy flotation

Goal-Oriented Control Systems(GOCS):From HOW to WHAT

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IEEE/CAA Journal of Automatica Sinica 2024年第4期11卷 816-819页

作者： wen-Hua Chen the Department of Aeronautical and Automotive Engineering Loughborough UniversityLeicestershireLE113TUU.K.

Brief:New control theory is required to underpin safe design and deployment of future highly automated systems to deal with uncertain environments and complicated tasks,enabled by AI and other advanced ***-Oriented Control Systems offer potential to transform the control system design from currently instructing a control system how to perform a task to specifying what is to be achieved.

关键词： automated instru system

Flow characteristics and bubble statistics during the fragmentation process of the ingested main cavity in plunging breaking waves

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Journal of Hydrodynamics 2024年第3期36卷 546-555页

作者： wen-bin Zhang Wei-wen Zhao De-cheng Wan Computational Marine Hydrodynamics Lab(CMHL) School of Naval ArchitectureOcean and Civil EngineeringShanghai Jiao Tong UniversityShanghai200240China

Plunging breaking waves play an important role in the exchange of heat,momentum,and mass between the atmosphere and *** this paper,a series of direct numerical simulations is conducted to investigate the fragmentation process of the ingested main cavity in plunging breaking *** two-phase Navier-Stokes equations are solved using the finite-volume method based on adaptive refinement *** free surface is captured using a geometrical volume of fluid *** 2-D,3-D simulations are *** flow fields at different stages of wave breaking are presented and quantitative analysis for bubbles is *** 2-D instantaneous vorticity field and local velocity field are visualized to discuss the general flow characteristics during the fragmentation *** a 2-D parametric study is conducted to investigate the differences in the flow characteristics during the fragmentation process under different wave parameters including initial wave steepness(ε),Bond number(Bo),and Reynolds number(Re).3-D vortex structures are shown to further investigate the mechanisms behind the differences in the flow *** bubble size distributions under two different initial wave steepness are also discussed with their relationship to the fragmentation process of the ingested main *** research offers a significant understanding of the distinct procedures and fundamental dynamics involved in wave breaking,enhancing our comprehension of this intricate event.

关键词： Plunging breaking waves multiphase flow bubble statistics

Isotopic insights on quantitative assessments of interaction of eco-hydrological processes in multi-scale karst watersheds

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International Soil and Water Conservation Research 2024年第1期12卷 156-170页

作者： Zhuo Hao Yang Gao Qingwen Zhang wen wen Agricultural Clean Watershed Research Group Institute of Environment and Sustainable Development in AgricultureCAASBeijing100081China Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchCASBeijing100101China School of Humanities and Social Sciences Beijing Institute of TechnologyBeijing100081China

The dynamics of hydrological processes and the storage mechanisms of karst water resources are the most important issues in karst *** impact of environmental changes on water quantity,and the evaluation and quantification of eco-hydrological processes remain poorly *** this study,high-frequency continuous monitoring in multi-scale karst watersheds in Southwest China combined the approaches of water isotopes and the hybrid single-particle lagrangian integrated trajectory(HYSPLIT)model to identify the recharge mechanisms between atmospheric vapor,rainfall,surface water,and groundwater,and to reveal the interaction of eco-hydrological *** dominant moisture sources in Puding(PD)County were the Indian Ocean(43-69%)and local moisture(24-33%).Theδ^(18)O and deuterium excess(d-excess)values showed a positive correlation indicating that secondary or sub-cloud evaporation was prominent in the wet *** water line-conditioned excess(lc-excess)indicated that karst water interacted with recent precipitation,groundwater,and evaporation across *** to its specific hydrogeological structure,surface water and rainwater have a higher contribution rate to groundwater *** Chenqi stream replenished the Houzhai River mainly in the form of groundwater,with percentages ranging from 38.1 to 93.5%in the wet season,and 47.8-80.1%in the dry *** the Houzhai outlet,surface water and groundwater interconverted frequently with a percentage of 45.6-49.1%.We believe this is the first systematic study to quantify the supply relationship between water vapor transport,rainfall,surface water and groundwater in the Chinese karst zone,making a significant move forward in the field of karst hydrological processes and improving the efficiency of water resource evaluation and management.

关键词： Stable isotope Moisture sources Water cycle Karst watersheds

State of the art of lightweight aggregates used in lightweight refractories for working lining of high-temperature furnaces

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Journal of Iron and Steel Research International 2024年第6期31卷 1320-1343页

作者： Wei Zhang wen-yong Dai Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016LiaoningChina Research and Development Department AGC Plibrico(Dalian)Industries Inc.Dalian 116600LiaoningChina

Lightweight refractories for the working lining of high-temperature furnaces play an important role in the smelting of advanced steels and *** prepare lightweight refractories for the working lining of high-temperature furnaces,the synthesis of lightweight aggregates is the ***,the research on the synthesis of lightweight aggregates with high service temperature,low thermal conductivity,high strength,and good slag resistance has received widespread *** available literature on the synthesis of lightweight aggregates was summarized,including corundum,mullite,mullite-corundum,spinel,corundum-spinel,cordierite,cordierite-mullite,calcium hexaluminate,corundum-calcium hexaluminate,bauxite,magnesia,magnesia-based,and forsterite-based ***,the future development trend of lightweight aggregates was proposed.

关键词： Lightweight aggregate Lightweight refractory Working lining Apparent porosity Closed porosity Thermal conductivity Pore-forming approach

In situ embedded bismuth nanoparticles among highly porous carbon fibers for efficient carbon dioxide reduction

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Rare Metals 2024年第9期43卷 4312-4320页

作者： Wei-Jian Guo Ao Zhou wen-wen Cai Jin-Tao Zhang Key Laboratory for Colloid and Interface Chemistry (Ministry of Education) School of Chemistry and Chemical EngineeringShandong University

Electrocatalysis provides an optimal approach for the conversion of carbon dioxide(CO2) into high-value chemicals, thereby presenting a promising avenue toward achieve carbon neutrality. However, addressing the selectivity and stability challenges of metal catalysts in electrolytic reduction remains a daunting task. In this study, the electrospinning method is employed to fabricate porous carbon nanofibers loaded with bismuth nanoparticles with the help of in situ pyrolysis. The porous carbon nanofibers as conductive support would facilitate the dispersion of bismuth active sites while inhibiting their aggregation and promoting the mass transfer, thus enhancing their electrocatalytic activity and stability. Additionally, nitrogen doping induces electron delocalization in bismuth atoms through metal-support interactions, thus enabling efficient adsorption of intermediates for improving selectivity based on the theoretical calculation. Consequently, Bi@PCNF-500 exhibits the exceptional selectivity and stability across a wide range of potential windows. Notably, its faradaic efficiency(FE) of formate reaches 92.7% in H-cell and94.9% in flow cell, respectively, with good electrocatalytic stability. The in situ characterization and theoretical calculations elucidate the plausible reaction mechanism to obtain basic rules for designing efficient electrocatalyst.

关键词： Carbon dioxide reduction Electron delocalization N-doping Porous carbon nanofiber

Weakly Approximate Diagonalization of Homomorphisms into Finite von Neumann Algebras

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Acta Mathematica Sinica,English Series 2024年第9期40卷 2187-2194页

作者： wen Hua QIAN Jun Hao SHEN wen Ming WU School of Mathematical Sciences Chongqing Normal UniversityChongqing 401331P.R.China Department of Mathematics and Statistics University of New HampshireDurhamNH 03824USA

Let A be a unital C^(∗)-algebra and B a unital C^(∗)-algebra with a faithful traceτ.Let n be a positive *** give the definition of weakly approximate diagonalization(with respect toτ)of a unital homomorphismφ:A→Mn(B).We give an equivalent characterization of McDuff Ⅱ_(1) *** show that,if A is a unital nuclear C^(∗)-algebra and B is a type Ⅱ_(1) factor with faithful traceτ,then every unital^(∗)-homomorphism φ:A→M_(n)(B)is weakly approximately *** B is a unital simple infinite dimensional separable nuclear C^(∗)-algebra,then any finitely many elements in Mn(B)can be simultaneously weakly approximately diagonalized while the elements in the diagonals can be required to be the same.

关键词： Weakly approximately diagonalizable McDuff factors nuclear hyperfinite

A combined Liouville integrable hierarchy associated with a fourth-order matrix spectral problem

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Communications in Theoretical Physics 2024年第7期76卷 1-8页

作者： wen-Xiu Ma Department of Mathematics Zhejiang Normal UniversityJinhua 321004China Department of Mathematics King Abdulaziz UniversityJeddah 21589Saudi Arabia Department of Mathematics and Statistics University of South Florida TampaFL 33620-5700United States of America Material Science Innovation and Modelling Department of Mathematical SciencesNorth-West UniversityMafikeng CampusMmabatho 2735South Africa

This paper aims to propose a fourth-order matrix spectral problem involving four potentials and generate an associated Liouville integrable hierarchy via the zero curvature formulation.A bi-Hamiltonian formulation is furnished by applying the trace identity and a recursion operator is explicitly worked out,which exhibits the Liouville integrability of each model in the resulting *** specific examples,consisting of novel generalized combined nonlinear Schrodinger equations and modified Korteweg-de Vries equations,are given.

关键词： integrable hierarchy Hamiltonian structure zero curvature equation Lax pair matrix spectral problem

Effect of nano-carbon black content on wetting phenomenon of molten steel and alumina-carbon ceramic filter substrates

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Journal of Iron and Steel Research International 2024年第8期31卷 1900-1913页

作者： Jin-wen Song wen Yan Zhe Chen Ying Liu Shao-song Hong The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina National-provincial Joint Engineering Research Center of High Temperature Materials and Lining Technology Wuhan University of Science and TechnologyWuhan 430081HubeiChina Jiangsu Sheng Nai New Materials Co. Ltd.Taizhou 225503JiangsuChina

The effect of nano-carbon black content(O,8 and 12 wt.%)on the wettability of molten steel on Al_(2)O_(3)-C substrates was investigated by the sessile drop wetting method at 1500℃ under argon *** the beginning of the wetting experiment,the contact angle decreased with the increase in nano-carbon black *** the wetting experiment progressed,FeAl_(2)0_(4) layer and sheet Al_(2)O_(3) layer were found at the interface between the molten steel and the Al_(2)O_(3)-C substrates with O and 8 wt.% nano-carbon black content,and the contact angle deceased with *** the content of nano-carbon black was 12 wt.%,a large number of nano-Al_(2)O_(3) whiskers were observed,which made the contact angle between the molten steel and Al_(2)O_(3)-C substrate become *** on the scanning electron microscope and energy dispersive spectrometry results,the formation mechanism of FeAl2O4 layer and Al_(2)O_(3) layer and the interfacial reaction mechanism were proposed.

关键词： Contact angle Nano-carbon black Al_(2)O_(3)-C substrate Molten steel Interfacial reaction