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The Correlation between the Power Quality Indicators and Entropy Production Characteristics of Wind Power+Energy Storage Systems
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作者 Caifeng Wen Boxin Zhang +3 位作者 Yuanjun Dai Wenxin Wang Wanbing Xie Qian Du 《Energy Engineering》 EI 2024年第10期2961-2979,共19页
Power quality improvements help guide and solve the problems of inefficient energy production and unstable power output in wind power systems.The purpose of this paper is mainly to explore the influence of different e... Power quality improvements help guide and solve the problems of inefficient energy production and unstable power output in wind power systems.The purpose of this paper is mainly to explore the influence of different energy storage batteries on various power quality indicators by adding different energy storage devices to the simulated wind power system,and to explore the correlation between systementropy generation and various indicators,so as to provide a theoretical basis for directly improving power quality by reducing loss.A steady-state experiment was performed by replacing the wind wheel with an electric motor,and the output power qualities of the wind power systemwith andwithout energy storagewere compared and analyzed.Moreover,the improvement effect of different energy storage devices on various indicatorswas obtained.Then,based on the entropy theory,the loss of the internal components of the wind power system generator is simulated and explored by Ansys software.Through the analysis of power quality evaluation indicators,such as current harmonic distortion rate,frequency deviation rate,and voltage fluctuation,the correlation between entropy production and each evaluation indicator was explored to investigate effective methods to improve power quality by reducing entropy production.The results showed that the current harmonic distortion rate,voltage fluctuation,voltage deviation,and system entropy production are positively correlated in the tests and that the power factor is negatively correlated with system entropy production.In the frequency range,the frequency deviationwas not significantly correlated with the systementropy production. 展开更多
关键词 Wind power system entropy production system losses power quality indexes battery energy storage
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Ionization Engineering of Hydrogels Enables Highly Efficient Salt‑Impeded Solar Evaporation and Night‑Time Electricity Harvesting 被引量:4
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作者 Nan He Haonan Wang +3 位作者 Haotian Zhang Bo Jiang Dawei Tang Lin Li 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第1期131-146,共16页
Interfacial solar evaporation holds immense potential for brine desalination with low carbon footprints and high energy utilization.Hydrogels,as a tunable material platform from the molecular level to the macroscopic ... Interfacial solar evaporation holds immense potential for brine desalination with low carbon footprints and high energy utilization.Hydrogels,as a tunable material platform from the molecular level to the macroscopic scale,have been considered the most promising candidate for solar evaporation.However,the simultaneous achievement of high evaporation efficiency and satisfactory tolerance to salt ions in brine remains a challenging scientific bottleneck,restricting the widespread application.Herein,we report ionization engineering,which endows polymer chains of hydrogels with electronegativity for impeding salt ions and activating water molecules,fundamentally overcoming the hydrogel salt-impeded challenge and dramatically expediting water evaporating in brine.The sodium dodecyl benzene sulfonate-modified carbon black is chosen as the solar absorbers.The hydrogel reaches a ground-breaking evaporation rate of 2.9 kg m−2 h−1 in 20 wt%brine with 95.6%efficiency under one sun irradiation,surpassing most of the reported literature.More notably,such a hydrogel-based evaporator enables extracting clean water from oversaturated salt solutions and maintains durability under different high-strength deformation or a 15-day continuous operation.Meantime,on the basis of the cation selectivity induced by the electronegativity,we first propose an all-day system that evaporates during the day and generates salinity-gradient electricity using waste-evaporated brine at night,anticipating pioneer a new opportunity for all-day resource-generating systems in fields of freshwater and electricity. 展开更多
关键词 Solar evaporation Hydrogel evaporators Salt impeding Ionization engineering Cyclic vapor-electricity generation
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A review on global spatial distribution,sources and toxicity of perfluoroalkyl acid and prospect in the cryosphere
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作者 LI Bowen Du Wentao +5 位作者 KANG Shichang CHEN Jizu JIANG Youyan YIN Lichen LU Changsheng LIU Hongyi 《Journal of Mountain Science》 2025年第1期167-183,共17页
Perfluoroalkyl acid analogs(PFAAs)are a class of chemically stable environmentally persistent organic pollutants(POPs)that are difficult to degrade and have a strong capacity to accumulate in the human body.PFAAs have... Perfluoroalkyl acid analogs(PFAAs)are a class of chemically stable environmentally persistent organic pollutants(POPs)that are difficult to degrade and have a strong capacity to accumulate in the human body.PFAAs have been found to be biotoxic to humans and have been detected in various environmental media,especially in the cryosphere at trace concentrations.The cryosphere,sensitively responds to climate change,plays a crucial role in the global water,carbon and energy cycles.However,researches on cryosphere PFAAs especially in Tibetan Plateau(TP)is limited.Therefore,we summarize the physicochemical properties,physiological toxicity,spatiotemporal distribution,sources,diffusion and migration pathways,as well as analysis and removal methods of PFAAs in the cryosphere regions.The results show that PFAAs pollutants are mainly produced and distributed in the more economically developed countries in Europe and the United States,as well as in East Asia,and PFAAs can be transported by atmospheric circulation and water cycle to remote regions including cryosphere regions.The current detection methods for PFAAs in cryosphere need to be further refined for increased accuracy and convenience.There is also a need to develop more effective removal methods that will reduce the environmental and human threats posed by these PFAAs.Finally,we propose key scientific questions for future research in cryosphere including PFAAs redistribution influenced by cryosphere changes,human activities,and the interaction of other spheres. 展开更多
关键词 Perfluoroalkyl acid CRYOSPHERE Physiological toxicity Analytical method Removal method
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Mechanical response and dilatancy characteristics of deep marble under different stress paths:A sight from energy dissipation
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作者 LIU Xiao-hui HAO Qi-jun +2 位作者 ZHENG Yu ZHANG Zhao-peng XUE Yang 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第6期2070-2086,共17页
Dilatancy is a fundamental volumetric growth behavior observed during loading and serves as a key index to comprehending the intricate nonlinear behavior and constitutive equation structure of rock.This study focuses ... Dilatancy is a fundamental volumetric growth behavior observed during loading and serves as a key index to comprehending the intricate nonlinear behavior and constitutive equation structure of rock.This study focuses on Jinping marble obtained from the Jinping Underground Laboratory in China at a depth of 2400 m.Various uniaxial and triaxial tests at different strain rates,along with constant confining pressure tests and reduced confining pressure tests under different confining pressures were conducted to analyze the mechanical response and dilatancy characteristics of the marble under four stress paths.Subsequently,a new empirical dilatancy coefficient is proposed based on the energy dissipation method.The results show that brittle failure characteristics of marble under uniaxial compression are more obvious with the strain rate increasing,and plastic failure characteristics of marble under triaxial compression are gradually strengthened.Furthermore,compared to the constant confining pressure,the volume expansion is relatively lower under unloading condition.The energy dissipation is closely linked to the process of dilatancy,with a rapid increase of dissipated energy coinciding with the beginning of dilatancy.A new empirical dilatancy coefficient is defined according to the change trend of energy dissipation rate curve,of which change trend is consistent with the actual dilatancy response in marble under different stress paths.The existing empirical and theoretical dilatancy models are analyzed,which shows that the empirical dilatancy coefficient based on the energy background is more universal. 展开更多
关键词 deep marble stress paths DILATANCY energy dissipation empirical dilatancy coefficient
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Short-Term Prediction of Photovoltaic Power Based on DBSCAN-SVM Data Cleaning and PSO-LSTM Model
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作者 Yujin Liu Zhenkai Zhang +3 位作者 Li Ma Yan Jia Weihua Yin Zhifeng Liu 《Energy Engineering》 EI 2024年第10期3019-3035,共17页
Accurate short-termphotovoltaic(PV)power prediction helps to improve the economic efficiency of power stations and is of great significance to the arrangement of grid scheduling plans.In order to improve the accuracy ... Accurate short-termphotovoltaic(PV)power prediction helps to improve the economic efficiency of power stations and is of great significance to the arrangement of grid scheduling plans.In order to improve the accuracy of PV power prediction further,this paper proposes a data cleaning method combining density clustering and support vector machine.It constructs a short-termPVpower predictionmodel based on particle swarmoptimization(PSO)optimized Long Short-Term Memory(LSTM)network.Firstly,the input features are determined using Pearson’s correlation coefficient.The feature information is clustered using density-based spatial clustering of applications withnoise(DBSCAN),and then,the data in each cluster is cleanedusing support vectormachines(SVM).Secondly,the PSO is used to optimize the hyperparameters of the LSTM network to obtain the optimal network structure.Finally,different power prediction models are established,and the PV power generation prediction results are obtained.The results show that the data methods used are effective and that the PSO-LSTM power prediction model based on DBSCAN-SVM data cleaning outperforms existing typical methods,especially under non-sunny days,and that the model effectively improves the accuracy of short-term PV power prediction. 展开更多
关键词 Photovoltaic power prediction LSTM network DBSCAN-SVM PSO deep learning
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Micro segment analysis of supercritical methane thermal-hydraulic performance and pseudo-boiling in a PCHE straight channel 被引量:2
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作者 Qian Li Zi-Jie Lin +3 位作者 Liu Yang Yue Wang Yue Li Wei-Hua Cai 《Petroleum Science》 SCIE EI CAS CSCD 2024年第2期1275-1289,共15页
The printed circuit heat exchanger(PCHE) is receiving wide attention as a new kind of compact heat exchanger and is considered as a promising vaporizer in the LNG process. In this paper, a PCHE straight channel in the... The printed circuit heat exchanger(PCHE) is receiving wide attention as a new kind of compact heat exchanger and is considered as a promising vaporizer in the LNG process. In this paper, a PCHE straight channel in the length of 500 mm is established, with a semicircular cross section in a diameter of 1.2 mm.Numerical simulation is employed to investigate the flow and heat transfer performance of supercritical methane in the channel. The pseudo-boiling theory is adopted and the liquid-like, two-phase-like, and vapor-like regimes are divided for supercritical methane to analyze the heat transfer and flow features.The results are presented in micro segment to show the local convective heat transfer coefficient and pressure drop. It shows that the convective heat transfer coefficient in segments along the channel has a significant peak feature near the pseudo-critical point and a heat transfer deterioration when the average fluid temperature in the segment is higher than the pseudo-critical point. The reason is explained with the generation of vapor-like film near the channel wall that the peak feature related to a nucleateboiling-like state and heat transfer deterioration related to a film-boiling-like state. The effects of parameters, including mass flow rate, pressure, and wall heat flux on flow and heat transfer were analyzed.In calculating of the averaged heat transfer coefficient of the whole channel, the traditional method shows significant deviation and the micro segment weighted average method is adopted. The pressure drop can mainly be affected by the mass flux and pressure and little affected by the wall heat flux. The peak of the convective heat transfer coefficient can only form at high mass flux, low wall heat flux, and near critical pressure, in which condition the nucleate-boiling-like state is easier to appear. Moreover,heat transfer deterioration will always appear, since the supercritical flow will finally develop into a filmboiling-like state. So heat transfer deterioration should be taken seriously in the design and safe operation of vaporizer PCHE. The study of this work clarified the local heat transfer and flow feature of supercritical methane in microchannel and contributed to the deep understanding of supercritical methane flow of the vaporization process in PCHE. 展开更多
关键词 Printed circuit heat exchanger Vaporization Supercritical methane Pseudo-boiling Micro segment analysis
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Numerical and experimental investigation into the evolution of the shock wave when a muzzle jet impacts a constrained moving body 被引量:1
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作者 Zijie Li Hao Wang +1 位作者 Changshun Chen Kun Jiang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第3期317-326,共10页
The gun-track launch system is a new special launch device that connects the track outside the muzzle.Because it is constrained by the track,the characteristics of development of the muzzle jet differ from those of th... The gun-track launch system is a new special launch device that connects the track outside the muzzle.Because it is constrained by the track,the characteristics of development of the muzzle jet differ from those of the traditional muzzle jet.Specifically,it changes from freely developing to doing so in a constrained manner,where this results in an asymmetric direction of flow as well as spatio-temporal coupling-induced interference between various shock waves and the formation of vortices.In this background,the authors of this article formulate and consider the development and characteristics of evolution of the muzzle jet as it impacts a constrained moving body.We designed simulations to test the gun-track launch system,and established a numerical model based on the dynamic grid method to explore the development and characteristics of propagation of disturbances when the muzzle jet impacted a constrained moving body.We also considered models without a constrained track for the sake of comparison.The results showed that the muzzle jet assumed a circumferential asymmetric shape,and tended to develop in the area above the muzzle.Because the test platform was close to the ground,the muzzle jet was subjected to reflections from it that enhanced the development and evolution of various forms of shock waves and vortices in the muzzle jet to exacerbate its rate of distortion and asymmetric characteristics.This in turn led to significant differences in the changes in pressure at symmetric points that would otherwise have been identical.The results of a comparative analysis showed that the constrained track could hinder the influence of reflections from the ground on the muzzle jet to some extent,and could reduce the velocity of the shock waves inducing the motion of the muzzle as well as the Mach number of the moving body.The work here provides a theoretical basis and the requisite technical support for applications of the gun-track launch system.It also sheds light on the technical bottlenecks that need to be considered to recover high-value warheads. 展开更多
关键词 Shock wave/vortex interference Muzzle jet Constrained boundary Dynamic grid
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Rapid and stable calcium-looping solar thermochemical energy storage via co-doping binary sulfate and Al–Mn–Fe oxides 被引量:1
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作者 Changjian Yuan Xianglei Liu +8 位作者 Xinrui Wang Chao Song Hangbin Zheng Cheng Tian Ke Gao Nan Sun Zhixing Jiang Yimin Xuan Yulong Ding 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第8期1290-1305,共16页
Solar thermochemical energy storage based on calcium looping(CaL)process is a promising technology for next-generation concentrated solar power(CSP)systems.However,conventional calcium carbonate(CaCO_(3))pellets suffe... Solar thermochemical energy storage based on calcium looping(CaL)process is a promising technology for next-generation concentrated solar power(CSP)systems.However,conventional calcium carbonate(CaCO_(3))pellets suffer from slow reaction kinetics,poor stability,and low solar absorptance.Here,we successfully realized high power density and highly stable solar thermochemical energy storage/release by synergistically accelerating energy storage/release via binary sulfate and promoting cycle stability,mechanical strength,and solar absorptance via Al–Mn–Fe oxides.The energy storage density of proposed CaCO_(3)pellets is still as high as 1455 kJ kg^(-1)with only a slight decay rate of 4.91%over 100 cycles,which is higher than that of state-of-the-art pellets in the literature,in stark contrast to 69.9%of pure CaCO_(3)pellets over 35 cycles.Compared with pure CaCO_(3),the energy storage power density or decomposition rate is improved by 120%due to lower activation energy and promotion of Ca^(2+)diffusion by binary sulfate.The energy release or carbonation rate rises by 10%because of high O^(2-)transport ability of molten binary sulfate.Benefiting from fast energy storage/release rate and high solar absorptance,thermochemical energy storage efficiency is enhanced by more than 50%under direct solar irradiation.This work paves the way for application of direct solar thermochemical energy storage techniques via achieving fast energy storage/release rate,high energy density,good cyclic stability,and high solar absorptance simultaneously. 展开更多
关键词 Calcium looping(CaL) Solar thermochemical Energy storage Binary sulfate Fast reaction kinetics
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Importance of oxygen-containing functionalities and pore structures of biochar in catalyzing pyrolysis of homologous poplar 被引量:1
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作者 Li Qiu Chao Li +6 位作者 Shu Zhang Shuang Wang Bin Li Zhenhua Cui Yonggui Tang Obid Tursunov Xun Hu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第1期200-211,共12页
Biochar and bio-oil are produced simultaneously in one pyrolysis process,and they inevitably contact and may interact,influencing the composition of bio-oil and modifying the structure of biochar.In this sense,biochar... Biochar and bio-oil are produced simultaneously in one pyrolysis process,and they inevitably contact and may interact,influencing the composition of bio-oil and modifying the structure of biochar.In this sense,biochar is an inherent catalyst for pyrolysis.In this study,in order to investigate the influence of functionalities and pore structures of biochar on its capability for catalyzing the conversion of homologous volatiles in bio-oil,three char catalysts(600C,800C,and 800AC)produced via pyrolysis of poplar wood at 600 or 800℃or activated at 800℃,were used for catalyzing pyrolysis of homologous poplar wood at 600℃,respectively.The results indicated that the 600C catalyst was more active than 800C and 800AC for catalyzing cracking of volatiles to form more gas(yield increase by 40.2%)and aromatization of volatiles to form more light or heavy phenolics,due to its abundant oxygen-containing functionalities acting as active sites.The developed pores of the 800AC showed no such catalytic effect but could trap some volatiles and allow their further conversion via sufficient aromatization.Nevertheless,the interaction with the volatiles consumed oxygen on 600C(decrease by 50%),enhancing the aromatic degree and increasing thermal stability.The dominance of deposition of carbonaceous material of a very aromatic nature over 800C and 800AC resulted in net weight gain and blocked micropores but formed additional macropores.The in situ diffuse reflectance infrared Fourier transform spectroscopy characterization of the catalytic pyrolysis indicated superior activity of 600C for removal of -OH,while conversion of the intermediates bearing C=O was enhanced over all the char catalysts. 展开更多
关键词 Poplar wood Catalytic pyrolysis Char catalyst Volatile-char interaction BIO-OIL
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Integration of Low-level Waste Heat Recovery and Liquefied Nature Gas Cold Energy Utilization 被引量:16
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作者 白菲菲 张早校 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2008年第1期95-99,共5页
Two novel thermal cycles based on Brayton cycle and Rankine cycle are proposed, respectively, which integrate the recovery of low-level waste heat and Liquefied Nature Gas (LNG) cold energy utilization for power gen... Two novel thermal cycles based on Brayton cycle and Rankine cycle are proposed, respectively, which integrate the recovery of low-level waste heat and Liquefied Nature Gas (LNG) cold energy utilization for power generation. Cascade utilization of energy is realized in the two thermal cycles, where low-level waste heat,low-temperature exergy and pressure exergy of LNG are utilized efficiently through the system synthesis. The simulations are carried out using the commercial Aspen Plus 10.2, and the results are analyzed. Compared with the conventional Brayton cycle and Rankine cycle, the two novel cycles bring 60.94% and 60% in exergy efficiency, respectively and 53.08% and 52.31% in thermal efficiency, respectively. 展开更多
关键词 recovery of low-level waste heat LNG cold energy utilization power generation cascade utilization
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Stress relief and crystal face transition process contribute to the stability of zinc anodes
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作者 Yuqian Li Chunhui Peng +2 位作者 Xiaotong Gao Huanrong Liu Wenju Wang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第12期593-603,共11页
Zn electrodes are suffering the dendrite growth owing to the enrichment of local space charge, distinct exposed face and residual stress. In this work, we investigated the crystal face properties and stress state of Z... Zn electrodes are suffering the dendrite growth owing to the enrichment of local space charge, distinct exposed face and residual stress. In this work, we investigated the crystal face properties and stress state of Zn foil through static energy calculations, dynamic crystal growth analysis and finite element simulation of stress states. Then thermal driven is deployed to modify the exposure face and residual stress of Zn foil, aiming for a dendrite-free electrode. The calculation of surface energies and simulation of crystal growth models for different crystal faces indicate that the(0 0 1) face can maintain stability during deposition. Inspired by this mechanism, the(1 0 1) exposed commercial Zn foil is modified by thermal processing. Firstly, the exposure level of the(0 0 1) face increases, though only the peak corresponding to the(0 0 2) crystal face is observed, due to the extinction effect of the densely packed plane(0 0 1) face.Further, the surface morphology becomes smooth and the stress is released with the progresses time.These stress relief and crystal face transition process strengthen the uniformity of ion distribution, and increase the interface stability during the crystal growth, which reduce the defect sites in the deposition.As a result, the Zn electrode exhibits tiny voltage hysteresis and outstanding cycle stability, which reveals improved electrochemical performance. Additionally, Li and Na can also be improved in exposed crystal faces and release strain energy through similar methods to enhance cycling stability. 展开更多
关键词 Zn metal anode Dendrite free Exposure of crystal-face Stress relief Stable deposition
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Model for seawater fouling and effects of temperature,flow velocity and surface free energy on seawater fouling 被引量:3
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作者 Dazhang Yang Jianhua Liu +1 位作者 Xiaoxue E Linlin Jiang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2016年第5期658-664,共7页
A kinetic model was proposed to predict the seawater fouling process in the seawater heat exchangers.The new model adopted an expression combining depositional and removal behaviors for seawater fouling based on the K... A kinetic model was proposed to predict the seawater fouling process in the seawater heat exchangers.The new model adopted an expression combining depositional and removal behaviors for seawater fouling based on the Kern–Seaton model.The present model parameters include the integrated kinetic rate of deposition(k d)and the integrated kinetic rate of removal(k r),which have clear physical signi ficance.A seawater-fouling monitoring device was established to validate the model.The experimental data were well fitted to the model,and the parameters were obtained in different conditions.SEM and EDX analyses were performed after the experiments,and the results show that the main components of seawater fouling are magnesium hydroxide and aluminum hydroxide.The effects of surface temperature,flow velocity and surface free energy were assessed by the model and the experimental data.The results indicate that the seawater fouling becomes aggravated as the surface temperature increased in a certain range,and the seawater fouling resistance reduced as the flow velocity of seawater increased.Furthermore,the effect of the surface free energy of metals was analyzed,showing that the lower surface free energy mitigates the seawater fouling accumulation. 展开更多
关键词 FOULING Seawater MODEL Surface temperature Flow velocity Surface free energy
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Geochemical modeling to aid experimental design for multiple isotope tracer studies of coupled dissolution and precipitation reaction kinetics
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作者 Mingkun Chen Peng Lu +1 位作者 Yongchen Song Chen Zhu 《Acta Geochimica》 EI CAS CSCD 2024年第1期1-15,共15页
It is a challenge to make thorough but efficient experimental designs for the coupled mineral dissolution and precipitation studies in a multi-mineral system, because it is difficult to speculate the best experimental... It is a challenge to make thorough but efficient experimental designs for the coupled mineral dissolution and precipitation studies in a multi-mineral system, because it is difficult to speculate the best experimental duration, optimal sampling schedule, effects of different experimental conditions, and how to maximize the experimental outputs prior to the actual experiments. Geochemical modeling is an efficient and effective tool to assist the experimental design by virtually running all scenarios of interest for the studied system and predicting the experimental outcomes. Here we demonstrated an example of geochemical modeling assisted experimental design of coupled labradorite dissolution and calcite and clayey mineral precipitation using multiple isotope tracers. In this study, labradorite(plagioclase) was chosen as the reactant because it is both a major component and one of the most reactive minerals in basalt. Following our isotope doping studies of single minerals in the last ten years, initial solutions in the simulations were doped withmultiple isotopes(e.g., Ca and Si). Geochemical modeling results show that the use of isotope tracers gives us orders of magnitude more sensitivity than the conventional method based on concentrations and allows us to decouple dissolution and precipitation reactions at near-equilibrium condition. The simulations suggest that the precise unidirectional dissolution rates can inform us which rate laws plagioclase dissolution has followed. Calcite precipitation occurred at near-equilibrium and the multiple isotope tracer experiments would provide near-equilibrium precipitation rates, which was a challenge for the conventional concentration-based experiments. In addition, whether the precipitation of clayey phases is the rate-limiting step in some multi-mineral systems will be revealed. Overall, the modeling results of multimineral reaction kinetics will improve the understanding of the coupled dissolution–precipitation in the multi-mineral systems and the quality of geochemical modeling prediction of CO_(2) removal and storage efficacy in the basalt systems. 展开更多
关键词 Kinetics FELDSPAR Isotope doping Near-equilibrium CO_(2)sequestration BASALT
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Isotopic dependence of the yield ratios of light fragments from different projectiles and their unified neutron skin thicknesses
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作者 Ting-Zhi Yan Shan Li 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第3期228-236,共9页
The yield ratios of neutron-proton(R(n/p))and^(3)H-^(3)He(R(^(3)H∕^(3)He))with reduced rapidity from 0 to 0.5 were simulated at 50 MeV/u even-even ^(36−56)Ca+^(40)Ca,even-even ^(48−78)Ni+^(58)Ni,and ^(100−139)Sn(ever... The yield ratios of neutron-proton(R(n/p))and^(3)H-^(3)He(R(^(3)H∕^(3)He))with reduced rapidity from 0 to 0.5 were simulated at 50 MeV/u even-even ^(36−56)Ca+^(40)Ca,even-even ^(48−78)Ni+^(58)Ni,and ^(100−139)Sn(every third isotopes)+112 Sn for full reduced impact parameters using the isospin-dependent quantum molecular dynamics(IQMD)model.The neutron and proton density distributions and root-mean-square radii of the reaction systems were obtained using the Skyrme-Hartree-Fock model,which was used for the phase space initialization of the projectile and target in IQMD.We defined the unified neutron skin thickness asΔRnp=<r^(2)>^(1∕2) n−<r^(2)>^(1∕2)p,which was negative for neutron-deficient nuclei.The unifiedΔRnp values for nuclei with the same relative neutron excess from different isotopic chains were nearly equal,except for extreme neutron-rich isotopes,which is a type of scaling behavior.The yield ratios of the three isotopic chain-induced reactions,which depended on the reduced impact parameter and unified neutron skin thickness,were studied.The results showed that both R(n/p)and R(^(3)H∕^(3)He)decreased with a reduced impact parameter for extreme neutron-deficient isotopes;however,they increased with reduced impact parameters for extreme neutron-rich isotopes,and increased with theΔRnp of the projectiles for all reduced impact parameters.In addition,a scaling phenomenon was observed betweenΔR np and the yield ratios in peripheral colli-sions from different isotopic chain projectiles(except for extreme neutron-rich isotopes).Thus,R(n/p)and R(^(3)H∕^(3)He)from peripheral collisions were suggested as experimental probes for extracting the neutron or proton skin thicknesses of non-extreme neutron-rich nuclei from different isotopic chains. 展开更多
关键词 Exotic nuclei Unified neutron skin thickness Yield ratios IQMD
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Simulation of nanofluid natural convection based on single-particle hydrodynamics in energy-conserving dissipative particle dynamics(eDPD)
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作者 Wei LU Shuo CHEN +1 位作者 Zhiyuan YU Jiayi ZHAO 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第8期1429-1446,共18页
In the present study,the nanofliud natural convection is investigated by the energy-conserving dissipative particle dynamics(eDPD)method,where the nanoparticles are considered at the single-particle level.The thermal ... In the present study,the nanofliud natural convection is investigated by the energy-conserving dissipative particle dynamics(eDPD)method,where the nanoparticles are considered at the single-particle level.The thermal expansion coefficientβand the viscosityμof the simulated system containing nanoparticles are calculated and found to be in close alignment with the previous simulation results.The single-particle hydrodynamics in e DPD enables simulations of nanofluid natural convection with higher Rayleigh numbers and greater nanoparticle volume fractions.Additionally,this approach is utilized to simulate the nanoparticle distribution during the enhanced heat transfer process in the nanofluid natural convection.The localized aggregation of nanoparticles enhances the heat transfer performance of the nanofluid under specific Rayleigh numbers and nanoparticles volume fractions. 展开更多
关键词 single-particle hydrodynamics energy-conserving dissipative particle dynamics(eDPD) nanoparticle NANOFLUID heat transfer
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Enhanced properties of stone coal-based composite phase change materials for thermal energy storage
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作者 Baoshan Xie Huan Ma +1 位作者 Chuanchang Li Jian Chen 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CSCD 2024年第1期206-215,共10页
Phase change materials (PCMs) can be incorporated with low-cost minerals to synthesize composites for thermal energy storage in building applications.Stone coal (SC) after vanadium extraction treatment shows potential... Phase change materials (PCMs) can be incorporated with low-cost minerals to synthesize composites for thermal energy storage in building applications.Stone coal (SC) after vanadium extraction treatment shows potential for secondary utilization in composite preparation.We prepared SC-based composite PCMs with SC as a matrix,stearic acid (SA) as a PCM,and expanded graphite (EG) as an additive.The combined roasting and acid leaching treatment of raw SC was conducted to understand the effect of vanadium extraction on promoting loading capacity.Results showed that the combined treatment of roasting at 900℃ and leaching increased the SC loading of the composite by 6.2%by improving the specific surface area.The loading capacity and thermal conductivity of the composite obviously increased by 127%and 48.19%,respectively,due to the contribution of 3wt% EG.These data were supported by the high load of 66.69%and thermal conductivity of 0.59 W·m^(-1)·K-1of the designed composite.The obtained composite exhibited a phase change temperature of 52.17℃,melting latent heat of 121.5 J·g^(-1),and good chemical compatibility.The SC-based composite has prospects in building applications exploiting the secondary utilization of minerals. 展开更多
关键词 thermal energy storage phase change material stone coal vanadium extraction secondary utilization
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Coordination of distinctive pesticide adjuvants and atomization nozzles on droplet spectrum evolution for spatial drift reduction
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作者 Shidong Xue Jingkun Han +3 位作者 Xi Xi Zhong Lan Rongfu Wen Xuehu Ma 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第2期250-262,共13页
Pesticide adjuvants,as crop protection products,have been widely used to reduce drift loss and improve utilization efficiency by regulating droplet spectrum.However,the coordinated regulation mechanisms of adjuvants a... Pesticide adjuvants,as crop protection products,have been widely used to reduce drift loss and improve utilization efficiency by regulating droplet spectrum.However,the coordinated regulation mechanisms of adjuvants and nozzles on droplet spectrum remain unclear.Here,we established the relationship between droplet spectrum evolution and liquid atomization by investigating the typical characteristics of droplet diameter distribution near the nozzle.Based on this,the regulation mechanisms of distinctive pesticide adjuvants on droplet spectrum were clarified,and the corresponding drift reduction performances were quantitively evaluated by wind tunnel experiments.It shows that the droplet diameter firstly shifts to the smaller due to the liquid sheet breakup and then prefers to increase caused by droplet interactions.Reducing the surface tension of sprayed liquid facilitates the uniform liquid breakup and increasing the viscosity inhibits the liquid deformation,which prolong the atomization process and effectively improve the droplet spectrum.As a result,the drift losses of flat-fan and hollow cone nozzles are reduced by about 50%after adding organosilicon and vegetable oil adjuvants.By contrast,the air induction nozzle shows a superior anti-drift ability,regardless of distinctive adjuvants.Our findings provide insights into rational adjuvant design and nozzle selection in the field application. 展开更多
关键词 Pesticide drift Spray droplets Particle size distribution Spray atomization Transport processes ADJUVANTS
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Numerical Simulation and Entropy Production Analysis of Centrifugal Pump with Various Viscosity
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作者 Zhenjiang Zhao Lei Jiang +2 位作者 Ling Bai Bo Pan Ling Zhou 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第11期1111-1136,共26页
The fluid’s viscosity significantly affects the performance of a centrifugal pump.The entropy production method and leakage are employed to analyze the performance changes under various viscosities by numerical simul... The fluid’s viscosity significantly affects the performance of a centrifugal pump.The entropy production method and leakage are employed to analyze the performance changes under various viscosities by numerical simulation and validated by experiments.The results showed that increasing viscosity reduces both the pump head and efficiency.In addition,the optimal operating point shifts to the left.Leakage is influenced by vortex distribution in the front chamber and boundary layer thickness in wear-ring clearance,leading to an initial increase and subsequent decrease in leakage with increasing viscosity.The total entropy production Spro,Total inside the pump rises with increasing viscosity.The different mechanisms dominate under varying conditions:Turbulent dissipation dominates at low viscosity.Under high-viscosity conditions,energy loss is primarily caused by direct dissipation Spro,D and wall entropy production Spro,W.This study provides a deeper and more objective understanding of the energy characteristics of centrifugal pumps handling fluids of various viscosity,potentially aiding in optimizing pump design and improving energy conversion efficiency. 展开更多
关键词 Centrifugal pump numerical simulation VISCOSITY LEAKAGE entropy production
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Effect of Liquid Temperature on Surface and Mechanical Characteristics of Al-Mg Alloy Treated with a Cavitating Waterjet
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作者 Can Kang Shifeng Yan +2 位作者 Haixia Liu Jie Chen Kejin Ding 《Fluid Dynamics & Materials Processing》 EI 2024年第11期2431-2442,共12页
The presented study aims to reveal the effect of liquid temperature on cavitation-induced erosion of an Al-Mgalloy. An experimental work was conducted using a submerged cavitating waterjet to impact the specimen surfa... The presented study aims to reveal the effect of liquid temperature on cavitation-induced erosion of an Al-Mgalloy. An experimental work was conducted using a submerged cavitating waterjet to impact the specimen surface.For a certain cavitation number and a given standoff distance, different liquid temperatures were considered.Accordingly, a comprehensive comparison was implemented by inspecting the mass loss and surface morphologyof the tested specimens. The results show that the cumulative mass loss increases continuously with the liquidtemperature. A cavitation zone with an irregular profile becomes evident as the cavitation treatment proceeds.Increasing the temperature promotes the generation of cavitation bubbles. Large erosion pits are induced aftersevere material removal. The microhardness increases with the distance from the target surface. At a liquidtemperature of 50℃, the microhardness fluctuates apparently with increasing the depth of indentation. 展开更多
关键词 Cavitation erosion Al-Mg alloy liquid temperature mass loss surface morphology MICROHARDNESS
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Ribosome-inspired electrocatalysts inducing preferential nucleation and growth of three-dimensional lithium sulfide for high-performance lithium-sulfur batteries
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作者 Zhen Wu Wenfeng He +7 位作者 Jiahui Yang Yunuo Gu Ruiqi Yang Yiran Sun Jiajia Yuan Xin Wang Junwu Zhu Yongsheng Fu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第7期517-526,共10页
Nucleation of lithium sulfide(Li_(2)S)induced by electrocatalysts plays a crucial role in mitigating the shut-tle effect.However,short-chain polysulfides on electrocatalysts surfaces tend to re-dissolve into elec-trol... Nucleation of lithium sulfide(Li_(2)S)induced by electrocatalysts plays a crucial role in mitigating the shut-tle effect.However,short-chain polysulfides on electrocatalysts surfaces tend to re-dissolve into elec-trolytes,delaying Li_(2)S supersaturation and its nucleation.In this study,we draw inspiration from the ribosome-driven protein synthesis process in cells to prepare ultrasmall nitrogen-doped MoS_(2) nanocrys-tals anchored on porous nitrogen-doped carbon networks(N-MoS_(2)-NC)electrocatalysts.Excitedly,the ex-situ SEM demonstrates that ribosome-inspired N-MoS_(2)-NC electrocatalysts induce early nucleation and rapid growth of three-dimensional Li_(2)s during discharge.Theoretical calculations reveal that the Li-s bond length in N-MoS_(2)-Li_(2)S(100)is shorter,and the corresponding interfacial formation energy is lower than in MoS_(2)-Li_(2)S(100).This accelerated conversion of lithium polysulfides to Li_(2)S can enhance the utilization of active substances and inhibit the shuttle effect.This study highlights the potential of ribosome-inspired N-MoS_(2)-NC in improving the electrochemical stability of Li-S batteries,providing valuable insights for future electrocatalyst design. 展开更多
关键词 Lithium-sulfur batteries ELECTROCATALYSTS Nanocrystals Ribosome-inspired Nucleation and growth
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