During the development of shale gas,various issues such as low individual well production,rapid decline,limited reservoir control,and low recovery rates have arisen.Enhancing shale gas reservoir recovery rates has con...During the development of shale gas,various issues such as low individual well production,rapid decline,limited reservoir control,and low recovery rates have arisen.Enhancing shale gas reservoir recovery rates has consistently been a focal point and challenge within the industry.Therefore,this paper employs molecular dynamic(MD)simulation methods to study the adsorption and diffusion characteristics of CH_(4)/CO_(2)at different temperatures and mixing ratios.It compares the effects of temperature and CH_(4)/CO_(2)molar ratio changes on the selectivity coefficient,adsorption capacity,and diffusion coefficient of CH_(4)/CO_(2).The paper also plots the displacement interface and the function of CH_(4)/CO_(2)injection/residual amounts over time.Furthermore,it analyzes the adsorption capacity of molecules on the graphene surface,the migration capacity of molecules in the slit,and the displacement process of CH_(4)by CO_(2)on the nanoscale,revealing the microscopic mechanism of CH_(4)/CO_(2)competitive adsorption and displacement.The research results indicate that the influence of temperature on the selectivity coefficient is not significant,with an average decrease of 3%for every 20 K rise in temperature.Pressure has a more pronounced effect on the selectivity coefficient,with values around 1.4 at low pressures and around 1.2 at high pressures.Elevating the mole fraction of CO_(2)in the binary gas mixture results in an increase in the total adsorption amount and an accelerated variation of adsorption amount with pressure.As the CH_(4)mole fraction rises,the diffusion coefficient of CH_(4)increases,while the diffusion coefficient of CO_(2)diminishes with an increasing CO_(2)mole fraction.Under identical conditions,CO_(2)exhibits a stronger adsorption capacity over CH_(4)in shale organic nanopores,resulting in a concave moon-shaped displacement interface in the model.The larger the pre-adsorption pressure of CO_(2),the more intense the movement of CO_(2)along the graphene surface,and the faster the diffusion speed of CO_(2)along the wall.In a displacement pore(the pore space used to provide the displacement location or site)with a diameter of 3 nm,at smaller pressure differentials(≤10 MPa),the residual amount of CH_(4)remains relatively stable without substantial alteration.However,at a pressure differential of 20 MPa,the residual amount of CH_(4)decreases rapidly,and the displacement efficiency significantly improves.展开更多
Nanoparticle-mediated drug delivery is recognized as a promising option for targeted treatment of atherosclerosis. In this paper, the Eulerian-Lagrangian technique is adopted to simulate the delivery of drug-loaded na...Nanoparticle-mediated drug delivery is recognized as a promising option for targeted treatment of atherosclerosis. In this paper, the Eulerian-Lagrangian technique is adopted to simulate the delivery of drug-loaded nanoparticles to patient-specific atherosclerotic plaque with the aid of an external magnetic field. Plaques and vascular walls are introduced as porous media formulated by the Darcy-Forchheimer model in this targeted transport process. The results demonstrate that the delivery efficiency of particles to atherosclerosis depends on the external magnetic field, such as configuration and intensity, in which the configuration angle of the current wire is a key factor and the double current wires have advantages over the single current wire. Meanwhile, the delivery efficiency gradually decreases as the distance between the plaque cap and the current wire increases. Further, although augmenting the current or magnetic susceptibility can generally improve the delivery efficiency of nanoparticles, this increase is not apparent when small-sized nanoparticles are employed as drug transport particles. The results obtained can potentially serve as the guideline to optimize regimens for the targeted therapy of atherosclerosis.展开更多
Treatment of aortic arch(AA)diseases is challenging for surgeons.Conventional open surgery remains the“gold standard”but is associated with significant morbidity and mortality despite improvements in techniques.In t...Treatment of aortic arch(AA)diseases is challenging for surgeons.Conventional open surgery remains the“gold standard”but is associated with significant morbidity and mortality despite improvements in techniques.In the last 2 decades,thoracic endovascular aortic repair(TEVAR)has become the first-line treatment for diseases of the descending aorta,and its indications have expanded gradually.Various strategies have been proposed to preserve supra-aortic branches in TEVAR:hybrid technique,chimney technique,fenestration technique(including custom-made fenestrated or“scalloped”stent grafts,in situ fenestration,and physician-modified fenestration),and branched stent grafts.Though acceptable outcomes of endovascular aortic repair have been documented,the evidence regarding its long-term safety and efficacy is lacking,and concerns remain about the risk of cerebrovascular events,retrograde type-A dissection,endoleaks,and branch occlusion.This review discusses the current status and progress of endovascular repair of the AA,and looks toward future trends.We believe that multidisciplinary collaboration of a“HENDO”team(professionals in hybrid repair,endovascular repair,open surgery,cardiovascular anesthesia,and genetics)is essential for future repair of the AA to provide the optimal treatment.展开更多
基金supported by the National Natural Science Foundation of China(Grant No.52222402,52234003 and 52074235)Sichuan Science and Technology Program(NO:2022JDJQ0009 and No.2023NSFSC0934)+2 种基金the Science and Technology Cooperation Project of the CNPC-SWPU Innovation Alliance(Grant No.2020CX020202)the Deep Marine Shale Gas Efficient Development Overseas Expertise Introduction Center for Discipline Innovation(111 Center)the China Postdoctoral Science Foundation(Grant No.2022M722638).
文摘During the development of shale gas,various issues such as low individual well production,rapid decline,limited reservoir control,and low recovery rates have arisen.Enhancing shale gas reservoir recovery rates has consistently been a focal point and challenge within the industry.Therefore,this paper employs molecular dynamic(MD)simulation methods to study the adsorption and diffusion characteristics of CH_(4)/CO_(2)at different temperatures and mixing ratios.It compares the effects of temperature and CH_(4)/CO_(2)molar ratio changes on the selectivity coefficient,adsorption capacity,and diffusion coefficient of CH_(4)/CO_(2).The paper also plots the displacement interface and the function of CH_(4)/CO_(2)injection/residual amounts over time.Furthermore,it analyzes the adsorption capacity of molecules on the graphene surface,the migration capacity of molecules in the slit,and the displacement process of CH_(4)by CO_(2)on the nanoscale,revealing the microscopic mechanism of CH_(4)/CO_(2)competitive adsorption and displacement.The research results indicate that the influence of temperature on the selectivity coefficient is not significant,with an average decrease of 3%for every 20 K rise in temperature.Pressure has a more pronounced effect on the selectivity coefficient,with values around 1.4 at low pressures and around 1.2 at high pressures.Elevating the mole fraction of CO_(2)in the binary gas mixture results in an increase in the total adsorption amount and an accelerated variation of adsorption amount with pressure.As the CH_(4)mole fraction rises,the diffusion coefficient of CH_(4)increases,while the diffusion coefficient of CO_(2)diminishes with an increasing CO_(2)mole fraction.Under identical conditions,CO_(2)exhibits a stronger adsorption capacity over CH_(4)in shale organic nanopores,resulting in a concave moon-shaped displacement interface in the model.The larger the pre-adsorption pressure of CO_(2),the more intense the movement of CO_(2)along the graphene surface,and the faster the diffusion speed of CO_(2)along the wall.In a displacement pore(the pore space used to provide the displacement location or site)with a diameter of 3 nm,at smaller pressure differentials(≤10 MPa),the residual amount of CH_(4)remains relatively stable without substantial alteration.However,at a pressure differential of 20 MPa,the residual amount of CH_(4)decreases rapidly,and the displacement efficiency significantly improves.
基金Project supported by the National Natural Science Foundation of China(Nos.11772046 and 81870345)。
文摘Nanoparticle-mediated drug delivery is recognized as a promising option for targeted treatment of atherosclerosis. In this paper, the Eulerian-Lagrangian technique is adopted to simulate the delivery of drug-loaded nanoparticles to patient-specific atherosclerotic plaque with the aid of an external magnetic field. Plaques and vascular walls are introduced as porous media formulated by the Darcy-Forchheimer model in this targeted transport process. The results demonstrate that the delivery efficiency of particles to atherosclerosis depends on the external magnetic field, such as configuration and intensity, in which the configuration angle of the current wire is a key factor and the double current wires have advantages over the single current wire. Meanwhile, the delivery efficiency gradually decreases as the distance between the plaque cap and the current wire increases. Further, although augmenting the current or magnetic susceptibility can generally improve the delivery efficiency of nanoparticles, this increase is not apparent when small-sized nanoparticles are employed as drug transport particles. The results obtained can potentially serve as the guideline to optimize regimens for the targeted therapy of atherosclerosis.
基金supported by the National Natural Science Foundation of China(81870345 and 81800400).
文摘Treatment of aortic arch(AA)diseases is challenging for surgeons.Conventional open surgery remains the“gold standard”but is associated with significant morbidity and mortality despite improvements in techniques.In the last 2 decades,thoracic endovascular aortic repair(TEVAR)has become the first-line treatment for diseases of the descending aorta,and its indications have expanded gradually.Various strategies have been proposed to preserve supra-aortic branches in TEVAR:hybrid technique,chimney technique,fenestration technique(including custom-made fenestrated or“scalloped”stent grafts,in situ fenestration,and physician-modified fenestration),and branched stent grafts.Though acceptable outcomes of endovascular aortic repair have been documented,the evidence regarding its long-term safety and efficacy is lacking,and concerns remain about the risk of cerebrovascular events,retrograde type-A dissection,endoleaks,and branch occlusion.This review discusses the current status and progress of endovascular repair of the AA,and looks toward future trends.We believe that multidisciplinary collaboration of a“HENDO”team(professionals in hybrid repair,endovascular repair,open surgery,cardiovascular anesthesia,and genetics)is essential for future repair of the AA to provide the optimal treatment.
