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Volatilization kinetics and mechanisms of arsenic during vacuum distillation
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作者 Lin ZOU Guo-long CHEN +4 位作者 Guo-zheng ZHA Wen-long JIANG Bao-qiang XU Bin YANG Da-chun LIU 《Transactions of Nonferrous Metals Society of China》 2026年第2期649-658,共10页
The volatilization characteristics and kinetic mechanisms of arsenic were investigated in the temperature range of 623−773 K and pressure ranges of 10−10000 Pa.The experimental results reveal that the evaporation rate... The volatilization characteristics and kinetic mechanisms of arsenic were investigated in the temperature range of 623−773 K and pressure ranges of 10−10000 Pa.The experimental results reveal that the evaporation rate increases with increasing temperature and decreasing pressure.Surface reaction control dominates at low pressures(<100 Pa),whereas diffusion control dominates at high pressures(>5000 Pa).The evaporation behavior is successfully described by an Arrhenius-type model for temperature dependence and Logistic model for pressure dependence.Key kinetic parameters,including the critical pressure,maximum evaporation rate and evaporation coefficient,were calculated.The evaporation coefficient varies between 0.010 and 0.223,and the critical pressures vary between 281 and 478 Pa with temperature. 展开更多
关键词 ARSENIC vacuum distillation evaporation rate kinetic modeling process optimization
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Polymer molecule as nucleating agent to modulate crystallization kinetics for efficient and stable organic solar cells
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作者 Xiaoyang Du Luye Cao +5 位作者 Jia Zhu Xinrui Li Hui Lin Gang Yang Caijun Zheng Silu Tao 《Journal of Energy Chemistry》 2026年第1期770-777,I0017,共9页
The crystallization and aggregation characteristics of the active layer components in organic solar cells(OSCs)are one of the core factors determining photovoltaic performance,influencing the entire process from light... The crystallization and aggregation characteristics of the active layer components in organic solar cells(OSCs)are one of the core factors determining photovoltaic performance,influencing the entire process from light absorption to charge separation,transport,and ultimately charge collection.Dynamic changes in crystallization and aggregation states can also disrupt the microstructure of the active layer,thus shortening the lifetime of the cell.In this study,a morphology modulation strategy is proposed to regulate the crystallization kinetics of non-fullerene acceptors by employing the polymer molecule PYIT as a nucleating agent.An appropriate amount of PYIT was first completely dissolved with the non-fullerene acceptor Y6 and left to stand for 24 h,followed by the fabrication of layer-by-layer processed OSCs.Experiments demonstrated that high crystallinity of PYIT allows it to act as a crystallization nucleus,promoting the crystallization,orientation consistency,and ordered stacking of the acceptor.These nanoscale structural optimizations facilitate efficient charge transport,enhance exciton dissociation efficiency,and suppress unfavorable energetic disorder.Consequently,not only was the power conversion efficiency(PCE)of D18-Cl/Y6-based layer-by-layer processed OSC increased from 18.08%to 19.13%,but the atmospheric stability and long-term lifetime of the OSCs were also significantly improved.Notably,this strategy is also applicable to indoor OSCs,and the PYIT-optimized device can achieve a PCE of 27.0%under 1000 lux light-emitting diode(LED,3200K)irradiation,which is superior to that of the control device(24.2%).This work develops a crystal engineering strategy that is able to simultaneously optimize the microscopic morphology and charge dynamics properties in OSCs,thereby achieving simultaneous improvement in efficiency and stability. 展开更多
关键词 Organic solar cells Layer-by-layer processing Nucleating agent Crystallization kinetics STABILITY
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Research progress on the kinetics of methane-carbon dioxide reforming catalyzed by nickel-based catalysts
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作者 HU Jingtao WU Jie +2 位作者 DENG Bangqiang LIU Dawei XU Long 《燃料化学学报(中英文)》 北大核心 2026年第2期21-45,共25页
Under the backdrop of“Carbon Peak and Carbon Neutrality”(dual carbon)goal in China,the methane-carbon dioxide reforming reaction has attracted considerable attention due to its environmental benefits of converting t... Under the backdrop of“Carbon Peak and Carbon Neutrality”(dual carbon)goal in China,the methane-carbon dioxide reforming reaction has attracted considerable attention due to its environmental benefits of converting two greenhouse gases(methane and carbon dioxide)into syngas and its promising industrial applications.Nickel(Ni)-based catalysts,with high catalytic activity,low cost,and abundant resources,are considered ideal candidates for industrial applications.In this article,three reaction kinetic models were briefly introduced,namely the Power-Law(PL)model,the Eley-Rideal(ER)model,and the Langmuir-Hinshelwood-Hougen-Watson(LHHW)model.Based on the LHHW model,the reaction kinetics and mechanisms of different catalytic systems were systematically discussed,including the properties of supports,the doping of noble metals and transition metals,the role of promoters,and the influence of the geometric and electronic structures of Ni on the reaction mechanism.Furthermore,the kinetics of carbon deposition and elimination on various catalysts were analyzed.Based on the reaction rate expressions for carbon elimination,the reasons for the high activity of transition metal iron(Fe)-doped catalysts and core-shell structured catalysts in carbon elimination were explained.Based on the detailed collation and comparative analysis of the reaction mechanisms and kinetic characteristics across diverse Ni-based catalytic systems,a theoretical guidance for the designing of high-performance catalysts was provided in this work. 展开更多
关键词 carbon dioxide reforming of methane CATALYST model kinetics carbon deposit
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Kinetics and morphological evolution mechanism of WO_(3) during non-isothermal hydrogen reduction
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作者 Rui-fang WANG Xiang ZHAN +3 位作者 Yong-qiang CHEN Shi-ming ZHANG Yu-si CHE Ji-lin HE 《Transactions of Nonferrous Metals Society of China》 2026年第2期628-637,共10页
The hydrogen reduction kinetics of tungsten trioxide(WO_(3))was investigated via non-isothermal thermogravimetric analysis.Under the local gas-solid reduction conditions,the particle morphology of tungsten powders was... The hydrogen reduction kinetics of tungsten trioxide(WO_(3))was investigated via non-isothermal thermogravimetric analysis.Under the local gas-solid reduction conditions,the particle morphology of tungsten powders was found to be consistent with that of raw material WO_(3).The removal of oxygen from tungsten oxide during hydrogen reduction led to the formation of porous structures between the reduced particles,which were obviously different from the polyhedral single-crystal configuration of tungsten powders obtained via chemical vapor deposition.Moreover,the two-stage hydrogen reduction mechanisms of WO_(3) under the local gas-solid reduction conditions can be described using the composite autocatalytic function.The activation energies of the first and second stages of the hydrogen reduction of WO_(3) were determined to be 121 and 135 kJ/mol,respectively. 展开更多
关键词 tungsten trioxide tungsten powder hydrogen reduction reaction kinetics particle morphology
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Co-Pyrolysis of CaO with Lignite Powder and Sawdust:Synergistic Effects and Model Characterization of Low-Temperature Convective Drying Kinetics of Municipal Sludge
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作者 Jin Huang Zihao Tang +2 位作者 Tingting Wu Hualiang Li Yanxin Hu 《Frontiers in Heat and Mass Transfer》 2026年第1期335-353,共19页
In order to explore the effects of CaO,lignite dust and sawdust on the drying characteristics ofmunicipal sludge at different concentrations,a three-factor three-level regression experiment was carried out based on th... In order to explore the effects of CaO,lignite dust and sawdust on the drying characteristics ofmunicipal sludge at different concentrations,a three-factor three-level regression experiment was carried out based on the results of thermogravimetric experiment and single factor experiment.By fitting three common mathematical models,the Page model with the highest fitting degree was selected to determine the most suitable mathematical model to describe the municipal sludge drying process.In addition,the Box-Behnken design principle in the response surface method was used to analyze the interaction of three factors on the drying characteristics of municipal sludge.The results of the study show that below 100℃is the optimal drying temperature range for municipal sludge.The results of single factor experiments showed that the order of influence of the three factors on sludge drying time was CaO concentration>sawdust concentration>lignite dust concentration.In the single factor experiment,the optimal process parameterswere CaOconcentration 3%,lignite powder concentration 7%,and sawdust concentration 7%.In themulti-factor interaction analysis,the interaction between CaO and sawdust had the most significant effect on the reduction of drying time,and the order of influence was as follows:CaO interaction with sawdust>lignite dust interaction with sawdust>CaO interaction with lignite powder.Further analysis showed that the optimal process ratio was 3%CaO concentration and 3%sawdust concentration. 展开更多
关键词 Response surface method low-temperature sludge drying drying kinetics interaction analysis
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Neurodegenerative processes of aging: A perspective of restoration through insulin-like growth factor-1
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作者 Rosana Crespo Claudia Herenu 《Neural Regeneration Research》 2026年第4期1562-1563,共2页
The aging process is an inexorable fact throughout our lives and is considered a major factor in develo ping neurological dysfunctions associated with cognitive,emotional,and motor impairments.Aging-associated neurode... The aging process is an inexorable fact throughout our lives and is considered a major factor in develo ping neurological dysfunctions associated with cognitive,emotional,and motor impairments.Aging-associated neurodegenerative diseases are characterized by the progressive loss of neuronal structure and function. 展开更多
关键词 neurodegenerative diseases neurodegenerative processes cognitive impairments progressive loss neuronal structure function develo ping neurological dysfunctions insulin growth factor RESTORATION aging process
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Thin-Layer Convective Solar Drying and Mathematical Modelling of the Drying Kinetics of Marrubium vulgare Leaves
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作者 Mohammed Benamara Boumediene Touati +1 位作者 Said Bennaceur Bendjillali Ridha Ilyas 《Energy Engineering》 2026年第1期393-416,共24页
This study explores the thin-layer convective solar drying of Marrubium vulgare L.leaves under conditions typical of sun-rich semi-arid climates.Drying experiments were conducted at three inlet-air temperatures(40℃,5... This study explores the thin-layer convective solar drying of Marrubium vulgare L.leaves under conditions typical of sun-rich semi-arid climates.Drying experiments were conducted at three inlet-air temperatures(40℃,50℃,60℃)and two air velocities(1.5 and 2.5 m·s^(-1))using an indirect solar dryer with auxiliary temperature control.Moisture-ratio data were fitted with eight widely used thin-layer models and evaluated using correlation coefficient(r),root-mean-square error(RMSE),and Akaike information criterion(AIC).A complementary heattransfer analysis based on Reynolds and Prandtl numbers with appropriate Nusselt correlations was used to relate flow regime to drying performance,and an energy balance quantified the relative contributions of solar and auxiliary heat.The logarithmic model consistently achieved the lowest RMSE/AIC with r>0.99 across all conditions.Higher temperature and air velocity significantly reduced drying time during the decreasing-rate period,with no constantrate stage observed.On average,solar input supplied the large majority of the thermal demand,while the auxiliary heater compensated short irradiance drops to maintain setpoints.These findings provide a reproducible dataset and a modelling benchmark for M.vulgare leaves,and they support energy-aware design of hybrid solar dryers formedicinal plants in sun-rich regions. 展开更多
关键词 Solar drying MODELLING Marrubiun vulgare L drying kinetics drying characteristic curve
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Crystallization kinetics modulation for efficient inverted inorganic perovskite solar cells
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作者 Jiahui Li Jianlong Chang +4 位作者 Yali Liu Shanshan Qi Pengyang Wang Ying Zhao Xiaodan Zhang 《Journal of Energy Chemistry》 2026年第2期513-520,I0012,共9页
Inorganic perovskite solar cells(IPSCs),due to their suitable bandgap and superior thermal stability,are ideal candidates for tandem solar cells combined with silicon.However,the development of inorganic perovskite so... Inorganic perovskite solar cells(IPSCs),due to their suitable bandgap and superior thermal stability,are ideal candidates for tandem solar cells combined with silicon.However,the development of inorganic perovskite solar cells has been hindered by suboptimal crystallization dynamics that generate detrimental defects in the perovskite lattice.Here,we propose 4-Methoxyphenylphosphonic Acid(4MPA)as a multifunctional additive to address this challenge.P=O in 4MPA establish strong coordination with undercoordinated Pb^(2+),while-OH engage in O...H-O hydrogen bonding interactions with DMSO,effectively weakening the solvent-[PbX_(6)]^(4-)octahedron interaction.This dual functionality facilitates complete and rapid DMA^(+)-to-Cs^(+)cation exchange while regulating crystallization kinetics,thereby optimizing crystal growth.Furthermore,π-π interactions between benzene rings significantly enhance the moisture resistance of the perovskite layer.The optimized device demonstrates a power conversion efficiency(PCE)of 21.35%,with unencapsulated devices retaining 93,63%of their initial efficiency after 200-hour continuous operation under ambient conditions(35%relative humidity). 展开更多
关键词 Inverted inorganic perovskite solar cells Crystallization kinetics Dual function Additive engineering
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Exploring the role of organofacies in governing kerogen kinetics:A case study of the Permian Gondwana coals from India
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作者 Monalisa Mallick Runcie Paul Mathews +7 位作者 Nihar Ranjan Kar Barnita Banerjee Subhasmit Dash E.V.S.S.K.Babu Srinivas Bikkina Vikram Partap Singh Satendra Kumar Gupta Vireswar Samanta 《Energy Geoscience》 2026年第1期29-54,共26页
This study investigates four Late Permian Gondwana coals from the Raniganj sub-basin,Damodar Valley and three Early Permian Gondwana coals from the Talcher sub-basin,Mahanadi Valley.The study aims to characterize the ... This study investigates four Late Permian Gondwana coals from the Raniganj sub-basin,Damodar Valley and three Early Permian Gondwana coals from the Talcher sub-basin,Mahanadi Valley.The study aims to characterize the kerogen type,hydrocarbon generation potential,thermal maturity,and organic matter composition,as well as to explore the impact of organic matter characteristics on kerogen kinetic parameters,utilizing multi proxy approach.The study further investigates the influence of the mineral matrix on kerogen decomposition kinetics.Based on the Rock-Eval parameters,Fourier transform infrared spectroscopy(FTIR)parameters,and vitrinite reflectance(R_(o)),the kerogen is primarily classified as immature/early mature TypeⅢkerogen derived from terrestrial land plants,with minor contribution from TypeⅡkerogen having mainly gas generating potential.The source of the organic matter,as determined by stable carbon isotopic composition(δ^(13)C_(org))values and C/N ratios indicates a primary input from C_(3) terrestrial plants.The presence of enriched collotelinites and liptinites,such as sporinite and resinite,provides evidence for the input of terrestrial higher plants,including both herbaceous and arborescent species.Various indices derived from maceral abundances,including the gelification index(GI),tissue preservation index(TPI),and vegetation index(VI),collectively indicate diverse depositional conditions which range from wet forest swamps to shallow water-covered wet forest swamps and even dry forest swamps.The variation in vitrinite macerals influenced the kerogen type and consequently impacted the kinetic parameters,viz.the distribution of activation energies(E_(a)),kerogen transformation ratio(KTR),and hydrocarbon generation rate(HGR).Among the Talcher coals,shaly coals exhibit different kerogen type and kerogen transformation.This dissimilarity can be attributed to variable maceral compositions.Unlike the Talcher samples,all Raniganj samples show consistent kinetic behaviour despite their sample type(coal/shaly coal)or kerogen type(TypeⅢ/mixed TypeⅡ/Ⅲ)owing to comparable liptinite/vitrinite maceral composition.This study reveals that whilst the presence of mineral matrix shifts the apparent E_(a) of kerogen through interactions like adsorption and catalysis,it does not significantly affect the kerogen type,HGR,or KTR of the studied coals. 展开更多
关键词 Gondwana coal Organic petrography Kerogen kinetics Rock-Eval pyrolysis Fourier transform infrared spectroscopy(FTIR)
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Dissolution kinetics of a low-grade oxide-sulfide copper ore with high silica content:Laboratory studies and statistical modeling
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作者 Hiva Farhadi Faramarz Doulati Ardejani +5 位作者 Sied Ziaedin Shafaei Tonkaboni Soroush Maghsoudy Roya Kafi Helia Tafakori Christoph Butscher Reza Taherdangkoo 《Acta Geochimica》 2026年第1期111-131,共21页
In this study,copper extraction from low-grade oxide-sulfide ores was investigated using a leaching method combined with response surface methodology(RSM)to optimize operational conditions and assess leaching kinetics... In this study,copper extraction from low-grade oxide-sulfide ores was investigated using a leaching method combined with response surface methodology(RSM)to optimize operational conditions and assess leaching kinetics.Given copper's extensive industrial applications,sustainable recovery from low-grade ores is critical.Five key parameters-acid concentration,leaching time,particle size,temperature,and solids percentage-were identified as major influences on copper recovery.The results revealed that leaching time and solids percentage,along with interactions between temperature-time and temperature-solids percentage,had the most significant effects.Optimal conditions for 80% copper recovery while minimizing iron recovery below 3% included an acid concentration of 1.21 mol L^(-1),a leaching time of 108 min,a particle size of 438μm,a temperature of 45℃,and a solids percentage of 18.2%.Leaching kinetics were analyzed using shrinking core models,with the Dickinson model best describing the process,showing an activation energy of 32.63 kJ mol^(-1),indicative of mixed diffusion and chemical reaction control.The final kinetic model effectively predicted the influence of key parameters.These findings highlight the importance of optimizing process variables and selecting suitable kinetic models to enhance extraction efficiency,reduce costs,and improve sustainability in copper recovery. 展开更多
关键词 Oxide-sulfi de ore Response surface methodology kinetic analysis Miduk copper mine Shrinking core model Copper leaching
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Entropy regulation induced hollow prismatic structural NiCoFeInZnV-based layered double hydroxide with prominent electrochemical kinetics and stability for aqueous zinc-ion batteries
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作者 Liu Yang Tao Zou +9 位作者 Haihui Wu Jiqing Zhang Xuekun Sui Wenjing Zhang Ende Feng Xiaohui Guan Bao Liu Jingru Bai Penggang Yin Guangsheng Wang 《Journal of Energy Chemistry》 2026年第1期274-283,I0007,共11页
Layered double hydroxides(LDHs)hold great promise as cathode materials for aqueous zinc-ion batteries(AZIBs).Nevertheless,they also face challenges of sluggish kinetics and rapid capacity loss.Herein,a conformational ... Layered double hydroxides(LDHs)hold great promise as cathode materials for aqueous zinc-ion batteries(AZIBs).Nevertheless,they also face challenges of sluggish kinetics and rapid capacity loss.Herein,a conformational entropy regulation strategy has been applied to surmount the shortcomings.A medium-entropy iron-based metal organic framework(MIL-88)derived NiCoFeInZnV-based layered double hydroxide with carbon loaded(ME-NiCoFeInZnV-LDH/C)has been first proposed and prepared with a designed method.The increased entropy optimizes electron conductivity and alleviates structure alteration and diffusion barrier during interactions with charge carriers,due to electron-induced effect and“cocktail”effect.Moreover,the nanosheet assembled hollow prismatic structures could homogenize flux distribution and electric field distribution.Therefore,the electrochemical kinetics,crystal structure stability,and activity could be dramatically improved.Leveraging the advantages of structure and composition regulation,Zn||ME-NiCoFeInZnV-LDH/C zinc battery delivers high specific capacities,rate performance,and cycling stability.This work proposes a novel and feasible medium-entropy strategy to prepare a high-performance cathode for advanced AZIBs,which is of prominent significance for the development of charge storage devices. 展开更多
关键词 Medium-entropy strategy ME-NiCoFeInZnV-LDH/C Nanosheet assembled hollow prismatic structures Aqueous zinc-ion batteries Improved electrochemical kinetics and activity
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Static softening mechanisms and recrystallization kinetics of martensitic heat-resistant steel 40Cr10Si2Mo in double-pass thermal deformation
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作者 Tong-Yao Yang Qing-Juan Wang +2 位作者 Zhong-Ze Du Jing Yang Zhi-Meng Yan 《Journal of Iron and Steel Research International》 2026年第1期210-227,共18页
Single-pass and double-pass high-temperature deformation experiments were conducted on 40Cr10Si2Mo steel using a Gleeble-3500 thermal simulator.The static recrystallization(SRX)behavior and recrystallization mechanism... Single-pass and double-pass high-temperature deformation experiments were conducted on 40Cr10Si2Mo steel using a Gleeble-3500 thermal simulator.The static recrystallization(SRX)behavior and recrystallization mechanisms of 40Cr10Si2Mo steel were investigated under deformation temperatures of 900-1100℃,deformation strains of 10%,20%,and 30%,and inter-pass times of 1-120 s.A static recrystallization fraction model was developed.The results showed that the SRX volume fraction increased with higher deformation temperature,larger deformation amount,and longer inter-pass time,with the deformation temperature having the most significant effect on SRX.During the deformation process,different process parameters led to different internal deformation mechanisms of the material.Static recovery and continuous static recrystallization(CSRX)dominated deformation at lower temperatures through progressive lattice rotation.In comparison,at higher temperatures,the deformation mechanism was dominated by CSRX and discontinuous static recrystallization(DSRX).The nucleation mechanisms of the SRX process were grain boundary bulging nucleation and subgrain merging nucleation,with grain boundary bulging present under all conditions.Subgrain merging nucleation could provide an additional nucleation mode at lower deformation temperatures or lower deformation amounts.Based on the traditional Avarmi equation,a modified model coefficient was used to establish the SRX kinetic model for 40Cr10Si2Mo steel.The linear correlation coefficient R^(2) between the predicted and experimental static recrystallization volume fraction was 0.96702,indicating high prediction accuracy. 展开更多
关键词 40Cr10Si2Mo steel Double-pass hot deformation Static softening Recrystallization mechanism Recrystallization kinetics
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A peridynamics modeling approach for pre-cracked rock cracking processes under impact by integrating Drucker-Prager plasticity model and efficient contact model
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作者 Jingzhi Tu Nengxiong Xu Gang Mei 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第1期179-195,共17页
In rock engineering,natural cracks in rock masses subjected to external loads tend to initiate and propagate,leading to potential safety hazards.To investigate the effect of cracking behavior on the mechanical propert... In rock engineering,natural cracks in rock masses subjected to external loads tend to initiate and propagate,leading to potential safety hazards.To investigate the effect of cracking behavior on the mechanical properties of rocks,the cracking processes of pre-cracked rocks have been extensively studied using numerical modeling methods.The peridynamics(PD)exhibits advantages over other numerical methods due to the absence of the requirements for remeshing and external crack growth criterion.However,for modeling pre-cracked rock cracking processes under impact,current PD implementations lack generally applicable rock constitutive models and impact contact models,which leads to difficulties in determining rock material parameters and efficiently calculating impact loads.This paper proposes a non-ordinary state-based peridynamics(NOSBPD)modeling method integrating the Drucker-Prager(DP)plasticity model and an efficient contact model to address the above problems.In the proposed method,the Drucker-Prager plasticity model is integrated into the NOSBPD,thereby equipping NOSBPD with the capability to accurately characterize the nonlinear stress-strain relationship inherent in rocks.An efficient contact model between particles and meshes is designed to calculate the impact loads,which is essentially a coupling method of PD with the finite element method(FEM).The effectiveness of the proposed NOSBPD modeling method is verified by comparison with other numerical methods and experiments.Experimental results indicate that the proposed method can effectively and accurately predict the 3D cracking processes of pre-cracked cracks under impact loading,and the maximum principal stress is the key driver behind wing crack formation in pre-cracked rocks. 展开更多
关键词 Pre-cracked rocks Cracking processes Non-ordinary state-based peridynamics (NOSBPD) Drucker-Prager plasticity model Efficient contact model
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Kinetics of the hydrogen absorption and desorption processes of hydrogen storage alloys: A review 被引量:25
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作者 Qian Li Xi Lin +4 位作者 Qun Luo Yuʼan Chen Jingfeng Wang Bin Jiang Fusheng Pan 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2022年第1期32-48,共17页
High hydrogen absorption and desorption rates are two significant index parameters for the applications of hydrogen storage tanks.The analysis of the hydrogen absorption and desorption behavior using the isothermal ki... High hydrogen absorption and desorption rates are two significant index parameters for the applications of hydrogen storage tanks.The analysis of the hydrogen absorption and desorption behavior using the isothermal kinetic models is an efficient way to investigate the kinetic mechanism.Multitudinous kinetic models have been developed to describe the kinetic process.However,these kinetic models were de-duced based on some assumptions and only appropriate for specific kinetic measurement methods and rate-controlling steps(RCSs),which sometimes lead to confusion during application.The kinetic analysis procedures using these kinetic models,as well as the key kinetic parameters,are unclear for many researchers who are unfamiliar with this field.These problems will prevent the kinetic models and their analysis methods from revealing the kinetic mechanism of hydrogen storage alloys.Thus,this review mainly focuses on the summarization of kinetic models based on different kinetic measurement methods and RCSs for the chemisorption,surface penetration,diffusion of hydrogen,nucleation and growth,and chemical reaction processes.The analysis procedures of kinetic experimental data are expounded,as well as the effects of temperature,hydrogen pressure,and particle radius.The applications of the kinetic models for different hydrogen storage alloys are also introduced. 展开更多
关键词 hydrogen storage metal hydrides hydrogen absorption process hydrogen desorption process kinetic models
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Investigating precipitation kinetics of multi-variantε-carbides in martensite steel manufactured by twin-roll casting process
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作者 Hong-bin Guo Gang Liu +7 位作者 Shui-ze Wang Yu-he Huang Hai-tao Zhao Xiang Li Zhi-jian Zhang Qing-xiao Feng Hua-long Li Xin-ping Mao 《Journal of Iron and Steel Research International》 2025年第6期1612-1626,共15页
The modified precipitation theory was employed to directly predict the multi-variantε-carbide precipitation from thermodynamics and growing and ripening kinetics.Three distinct variants were identified:Variants 1 and... The modified precipitation theory was employed to directly predict the multi-variantε-carbide precipitation from thermodynamics and growing and ripening kinetics.Three distinct variants were identified:Variants 1 and 2 were the perpendicular plate-likeε-carbides,while the granularε-carbides were Variant 3.The particle sizes of Variants 1 and 2 were usually larger than those of Variant 3.The mean aspect ratios of Variants 1 and 2 were 4.96,4.62 and 4.35 larger than those(1.72,1.63 and 1.56)for the granularε-carbides when coiled at 140,200 and 250℃,respectively.Thermodynamic analysis indicated that Variants 1 and 2 are easier to nucleate than Variant 3.The growing kinetic analysis implied that the relative nucleation time and precipitation time for Variants 1 and 2 were about 8 and 5 orders of magnitude less than those for Variant 3,respectively.The ripening kinetics further displayed that the ripening rate was similar for Variants 1,2 and 3.In addition,the dislocation density has weak influence onε-carbide nucleation.These findings suggest that the precipitation thermodynamic and kinetic models could be extended to second phase precipitation in other materials systems.Besides,nano-scaleε-carbides,fine block size and nano-twins,as well as medium-density dislocations,jointly caused the optimal match between strength and total elongation when coiled at 140℃. 展开更多
关键词 Twin-roll casting process Hot-rolled martensite steel ε-carbide precipitation Thermodynamics kinetics RIPENING Strengthening mechanism
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Thermodynamics and kinetics of alumina and magnesium oxide in calcium ferrite sintering process
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作者 Rende Chang Chengyi Ding +7 位作者 Hongming Long Xuewei Lü Tiejun Chun Xiaoqing Xu Zhiming Yan Xuchao Wang Sheng Xue Wei Lü 《International Journal of Minerals,Metallurgy and Materials》 2025年第7期1538-1550,共13页
Al_(2)O_(3)and MgO serve as the primary gangue components in sintered ores,and they are critical for the formation of CaO-Fe_(2)O_(3)-xAl_(2)O_(3)(wt%,C-F-xA)and CaO-Fe_(2)O_(3)-xM gO(wt%,C-F-xM)systems,respectively.I... Al_(2)O_(3)and MgO serve as the primary gangue components in sintered ores,and they are critical for the formation of CaO-Fe_(2)O_(3)-xAl_(2)O_(3)(wt%,C-F-xA)and CaO-Fe_(2)O_(3)-xM gO(wt%,C-F-xM)systems,respectively.In this study,a nonisothermal crystallization thermodynamics behavior of C-F-xA and C-F-xM systems was examined using differential scanning calorimetry,and a phase identification and microstructure analysis for C-F-xA and C-F-xM systems were carried out by X-ray diffraction and scanning electron microscopy.Results showed that in C-F-2A and C-F-2M systems,the increased cooling rates promoted the precipitation of CaFe_(2)O_(4)(CF)but inhibited the formation of Ca_(2)Fe_(2)O_(5)(C2F).In addition,C-F-2A system exhibited a lower theoretical initial crystallization temperature(1566 K)compared to the C-F system(1578 K).This temperature further decreases to 1554 K and 1528 K in the C-F-4A and C-F-8A systems,respectively.However,in C-F-xM system,the increased MgO content raised the crystallization temperature.This is because that the enhanced precipitation of MF(a spinel phase mainly comprised Fe_(3)O_(4)and MgFe_(2)O_(4))and C2F phases suppressed the CF precipitation reaction.In kinetic calculations,the Ozawa method revealed the apparent activation energies of the C-F-2A and C-F-2M systems.Malek's method revealed that the crystallization process in C-F-2A system initially followed a logarithmic law(lnαor lnα2),later transitioning to a reaction order law((1-α)-1or(1-α)^(-1/2),n=2/3)or the lnα2function of the exponential law.In C-F-2M system,it consistently followed the sequencef(α)=(1-α)^(2)(αis the crystallization conversion rate;n is the Avrami constant;?(α)is the differential equations for the model function of C_(2)F and CF crystallization processes). 展开更多
关键词 calcium ferrite ALUMINA magnesium oxide THERMODYNAMICS kinetics
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Al and V Leaching Kinetics During Preparation of Ti6Al4V Alloy Powders by Multistage Deep Reduction Process
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作者 Yan Jisen Liu Kaixuan +4 位作者 Jin Fengyi Dou Zhihe Zhang Tingan Xie Fang Hua Xijin 《稀有金属材料与工程》 北大核心 2025年第6期1426-1434,共9页
The leaching process of magnesiothermic self-propagating product generated during the multistage deep reduction process was investigated.The influence of magnesiothermic self-propagating product particle size,HCl solu... The leaching process of magnesiothermic self-propagating product generated during the multistage deep reduction process was investigated.The influence of magnesiothermic self-propagating product particle size,HCl solution concentration,and leaching solution temperature on the leaching behavior of elements Al and V was investigated.Results demonstrate that the leaching rate of Al and V is increased with the rise in leaching solution temperature,the increase in HCl solution concentration,and the enlargement of magnesiothermic self-propagating product particle size.The leaching processes of Al and V are consistent with the chemical reaction control model.When the magnesiothermic self-propagation product with D_(50) of 59.4μm is selected as the raw material,the leaching temperature is 40℃,and 1 mol/L HCl solution is employed,after leaching for 180 min,the leaching rates of Al and V are 24.8%and 12.6%,respectively.The acid-leached product exhibits a porous structure with a specific surface area of 3.5633 m^(2)/g. 展开更多
关键词 multistage deep reduction process Ti6Al4V alloy powder acid leaching magnesiothermic self-propagating
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Mechanism,kinetics and process assessment of efficient extraction of valuable metal from nickel sulfide ore by(NH_(4))_(2)S_(2)O_(8)direct oxidative leaching
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作者 Rui-min YANG Wen-ning MU +4 位作者 Yuan-hang ZHOU Jun-jin MENG Xue-fei LEI Shao-hua LUO Xue-yong DING 《Transactions of Nonferrous Metals Society of China》 2025年第12期4253-4265,共13页
A clean and efficient process for the direct extraction of valuable metals from low-grade nickel sulfide ore through oxidative leaching with(NH_(4))_(2)S_(2)O_(8)under atmosphere pressure was proposed to address the g... A clean and efficient process for the direct extraction of valuable metals from low-grade nickel sulfide ore through oxidative leaching with(NH_(4))_(2)S_(2)O_(8)under atmosphere pressure was proposed to address the growing demand for nickel and cobalt in the new energy industry.The effects of four key parameters on the metal leaching rates were systematically investigated.Characterization techniques,including XRD,SEM and EDS,were employed to analyze phase transformations during the leaching process.Under optimized conditions,approximately 96.5%of nickel,95.5%of cobalt and 65.2%of copper were successfully extracted.The kinetics of the leaching process was explored to identify the controlling mechanisms of nickel,cobalt and copper dissolution,establishing activation energies and kinetic equations for each metal.The cleanliness and efficiency of this method were confirmed through comparisons with other extraction processes for nickel sulfide ore. 展开更多
关键词 nickel sulfide ore ammonium persulfate oxidative leaching phase transformation leaching kinetics
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Modeling of austenite formation kinetics overlapping recrystallization in cold-rolled Q&P steel during ultrafast heating process
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作者 Jiang Chang Mai Wang +2 位作者 Yong-gang Yang Yan-xin Wu Zhen-li Mi 《Journal of Iron and Steel Research International》 2025年第11期3894-3907,共14页
The cold-rolled quenching and partitioning(Q&P)steel with an initial microstructure of deformed ferrite and pearlite was studied.The microstructural evolution under various heating rates of 1.78,50,and 300℃/s was... The cold-rolled quenching and partitioning(Q&P)steel with an initial microstructure of deformed ferrite and pearlite was studied.The microstructural evolution under various heating rates of 1.78,50,and 300℃/s was investigated using microstructural characterization and theoretical modeling.At the same time,the characteristics of recrystallization and austenite formation kinetics were decoupled by examining recrystallized ferrite and deformed ferrite as initial conditions.The findings revealed that the austenite formation during continuous heating can be simplified into two stages:(i)the early nucleation-dominated formation stage and(ii)the later grain growth-dominated stage,resulting in the development of a modified two-stage model based on Johnson-Mehl-Avrami-Kolmogorov.Further experiments confirmed that when the austenite volume fraction exceeded approximately 5% at a heating rate of 1.78℃/s,ferrite recrystallization was suppressed.In consequence,a mixed model including recrystallization kinetics was employed to couple the austenite formation occurring in deformed ferrite and recrystallized ferrite,thereby describing the austenite formation kinetics affected by recrystallization.Precise predictions of non-isothermal austenite formation kinetics in cold-rolled Q&P steel were achieved during slow and ultrafast heating processes by integrating the suppression effect into the model for austenite formation. 展开更多
关键词 Quenching and partitioning steel Ultrafast heating Ferrite recrystallization Austenite formation kinetic model
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Two stages kinetics of municipal solid waste inoculation composting processes 被引量:2
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作者 XIBei-dou HUANGGuo-he +1 位作者 QINXiao-sheng LIUHong-liang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2004年第3期520-524,共5页
In order to understand the key mechanisms of the composting processes, the municipal solid waste(MSW) composting processes were divided into two stages, and the characteristics of typical experimental scenarios from t... In order to understand the key mechanisms of the composting processes, the municipal solid waste(MSW) composting processes were divided into two stages, and the characteristics of typical experimental scenarios from the viewpoint of microbial kinetics was analyzed. Through experimentation with advanced composting reactor under controlled composting conditions, several equations were worked out to simulate the degradation rate of the substrate. The equations showed that the degradation rate was controlled by concentration of microbes in the first stage. The degradation rates of substrates of inoculation Run A, B, C and Control composting systems were 13 61 g/(kg·h), 13 08 g/(kg·h), 15 671 g/(kg·h), and 10 5 g/(kg·h), respectively. The value of Run C is around 1 5 times higher than that of Control system. The decomposition rate of the second stage is controlled by concentration of substrate. Although the organic matter degradation rates were similar to all Runs, inoculation could reduce the values of the half velocity coefficient K \-m and could be more efficient to make the composting stable. Particularly, for Run C, the degradation rate is high in the first stage, and K \-m is low in the second stage. The results indicated that the inoculation was efficient for the composting processes. 展开更多
关键词 municipal solid waste inoculation complex microbial community oxygen consumption two stages kinetics equations
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