Acetylene is produced from the reaction between calcium carbide(CaC_(2))and water,while the production of CaC_(2) generates significant amount of carbon dioxide not only because it is an energy-intensive process but a...Acetylene is produced from the reaction between calcium carbide(CaC_(2))and water,while the production of CaC_(2) generates significant amount of carbon dioxide not only because it is an energy-intensive process but also the raw material for CaC_(2) synthesis is from coal.Here,a comprehensive biomass-to-acetylene process was constructed that integrated several units including biomass pyrolysis,oxygen-thermal CaC_(2) fabrication and calcium looping.For comparison,a coal-to-acetylene process was also established by using coal as feedstock.The carbon efficiency,energy efficiency and environmental impacts of the bio-based calcium carbide acetylene(BCCA)and coal-based calcium carbide acetylene(CCCA)processes were systematically analyzed.Moreover,the environmental impacts were further evaluated by applying thermal integration at system level and energy substitution in CaC_(2) furnace.Even though the BCCA process showed lower carbon efficiency and energy efficiency than that of the CCCA process,life cycle assessment demonstrated the BCCA(1.873 kgCO_(2eq) kg-prod^(-1))a lower carbon footprint process which is 0.366 kgCO_(2eq) kg-prod^(-1) lower compared to the CCCA process.With sustainable energy(biomass power)substitution in CaC_(2) furnace,an even lower GWP value of 1.377 kgCO_(2eq) kg-prod^(-1) can be achieved in BCCA process.This work performed a systematic analysis on integrating biomass into industrial acetylene production,and revealed the positive role of biomass as raw material(carbon)and energy supplier.展开更多
In the carbonate industry,deep decarbonization strategies are necessary to effectively remediate CO_(2).These strategies mainly include both sustainable energy supplies and the conversion of CO_(2)in downstream proces...In the carbonate industry,deep decarbonization strategies are necessary to effectively remediate CO_(2).These strategies mainly include both sustainable energy supplies and the conversion of CO_(2)in downstream processes.This study developed a coupled process of biomass chemical looping H2 production and reductive calcination of CaCO_(3).Firstly,a mass and energy balance of the coupled process was established in Aspen Plus.Following this,process optimization and energy integration were implemented to provide optimized operation conditions.Lastly,a life cycle assessment was carried out to assess the carbon footprint of the coupled process.Results reveal that the decomposition temperature of CaCO_(3)in an H_(2)atmosphere can be reduced to 780℃(generally around 900℃),and the conversion of CO_(2)from CaCO_(3)decomposition reached 81.33%with an H2:CO ratio of 2.49 in gaseous products.By optimizing systemic energy through heat integration,an energy efficiency of 86.30%was achieved.Additionally,the carbon footprint analysis revealed that the process with energy integration had a low global warming potential(GWP)of-2.624 kg·kg^(-1)(CO_(2)/CaO).Conclusively,this work performed a systematic analysis of introducing biomass-derived H_(2)into CaCO_(3)calcination and demonstrated the positive role of reductive calcination using green H_(2)in mitigating CO_(2)emissions within the carbonate industry.展开更多
Development of an electrocatalyst that is cheap and has good properties to replace conventional noble metals is important for H_(2) applications.In this study,dealloying of an amorphous Ti_(37)Cu_(60)Ru_(3) alloy was ...Development of an electrocatalyst that is cheap and has good properties to replace conventional noble metals is important for H_(2) applications.In this study,dealloying of an amorphous Ti_(37)Cu_(60)Ru_(3) alloy was performed to prepare a freestanding nanostructured hydrogen evolution reaction(HER)catalyst.The effect of dealloying and addition of Ru to TiCu alloys on the microstructure and HER properties under alkaline conditions was investigated.3 at.%Ru addition in Ti_(40)Cu_(60) decreases the overpotential to reach a current density of 10mA cm^(-2) and Tafel slope of the dealloyed samples to 35 and 34mV dec−1.The improvement of electrocatalytic properties was attributed to the formation of a nanostructure and the modification of the electronic structure of the catalyst.First-principles calculations based on density function theory indicate that Ru decreases the Gibbs free energy of water dissociation.This work presents a method to prepare an efficient electrocatalyst via dealloying of amorphous alloys.展开更多
The issues of reducing CO_2 levels in the atmo-sphere, sustainably utilizing natural mineral resources,and dealing with indus trial waste offer challenging opportunities for sustainable development in energy and the e...The issues of reducing CO_2 levels in the atmo-sphere, sustainably utilizing natural mineral resources,and dealing with indus trial waste offer challenging opportunities for sustainable development in energy and the environment. The latest advances in CO_2 mineralization technology involving natural minerals and industrial waste are summarized in this paper, with great emphasis on the advancement of fundamental science, economic evaluation, and engineering applications. We discuss several lead-ing large-scale CO_2 mineralization methodologies from a techn ical and engineering-science perspective. For each technology option, we give an overview of the technical parameters, reaction pathway, reactivity, procedural scheme, and laboratorial and pilot devices. Furthermore, we present a discussion of each technology based on experimental results and the literature. Finally, current gaps in knowledge are identified in the conclusion, and an overview of the challenges and opportunities for future research in this field is provided.展开更多
With the emerging diverse applications in data centers,the demands on quality of service in data centers also become diverse,such as high throughput of elephant flows and low latency of deadline-sensitive flows.Howeve...With the emerging diverse applications in data centers,the demands on quality of service in data centers also become diverse,such as high throughput of elephant flows and low latency of deadline-sensitive flows.However,traditional TCPs are ill-suited to such situations and always result in the inefficiency(e.g.missing the flow deadline,inevitable throughput collapse)of data transfers.This further degrades the user-perceived quality of service(QoS)in data centers.To reduce the flow completion time of mice and deadline-sensitive flows along with promoting the throughput of elephant flows,an efficient and deadline-aware priority-driven congestion control(PCC)protocol,which grants mice and deadline-sensitive flows the highest priority,is proposed in this paper.Specifically,PCC computes the priority of different flows according to the size of transmitted data,the remaining data volume,and the flows’deadline.Then PCC adjusts the congestion window according to the flow priority and the degree of network congestion.Furthermore,switches in data centers control the input/output of packets based on the flow priority and the queue length.Different from existing TCPs,to speed up the data transfers of mice and deadline-sensitive flows,PCC provides an effective method to compute and encode the flow priority explicitly.According to the flow priority,switches can manage packets efficiently and ensure the data transfers of high priority flows through a weighted priority scheduling with minor modification.The experimental results prove that PCC can improve the data transfer performance of mice and deadline-sensitive flows while guaranting the throughput of elephant flows.展开更多
Metallic glasses(MGs)possess exceptional properties,but their properties consistently deteriorate over time,thereby resulting in increased complexity in processing.It thus poses a formidable challenge to the forming o...Metallic glasses(MGs)possess exceptional properties,but their properties consistently deteriorate over time,thereby resulting in increased complexity in processing.It thus poses a formidable challenge to the forming of long-term aged MGs.Here,we report ultrasonic vibration(UV)loading can lead to large plas-ticity and strong rejuvenation in significantly aged MGs within 1 s.A large UV-induced plasticity(UVIP)of 80%height reduction can be achieved in LaNiAl MG samples aged at 85%of its glass transition tem-perature(0.85 T_(g))for a duration of up to 1 month.The energy threshold required for UVIP monotonously increases with aging time.After the UV loading process,the aged samples show strong rejuvenation,with the relaxation enthalpy even surpassing that of as-cast samples.These findings suggest that UV loading is an effective technique for forming and rejuvenating aged MGs simultaneously,providing an alterna-tive avenue to explore the interplay between the property and microstructures as well as expanding the application prospects of MGs.展开更多
Utilizing ionic liquid(IL)-water mixtures as selective extraction solvents for raw materials from natural sources represents an efficacious approach;however,elucidating the underlying mechanisms inherent in various ty...Utilizing ionic liquid(IL)-water mixtures as selective extraction solvents for raw materials from natural sources represents an efficacious approach;however,elucidating the underlying mechanisms inherent in various types of IL-aqueous solutions continues to pose a significant challenge.In this study,molecular dynamics simulations and density functional theory calculations are employed to illuminate the influence of the functional anion within ILs and the water content on the solvation mechanism and phase separation phenomena observed during the extraction of camptothecin(CPT)using aqueous IL solutions.The simulation results show that the anions in ILs preferentially dissolve CPT through hydrogen bonding at low water concentrations.As the water concentration increases,the hydrophobic IL binds more tightly to CPT,enabling the water to self-aggregate.The anions in hydrophilic IL form hydrogen bonds with water instead,further enhancing the dissolution of CPT.This work reveals the mechanism of phase separation and solvation of different types of IL aqueous solutions,which is helpful in developing new drug extraction and purification technologies.展开更多
Wear resistance is a critical consideration in engineering applications.In this study,we demonstrated an Ir-Ta-Ni-Nb bulk metallic glass(BMG)with outstanding high-temperature wear resistance and revealed its promising...Wear resistance is a critical consideration in engineering applications.In this study,we demonstrated an Ir-Ta-Ni-Nb bulk metallic glass(BMG)with outstanding high-temperature wear resistance and revealed its promising applications in extreme environments.The wear behavior and mechanism were systemati-cally investigated from room temperature(RT)to 750℃.The results show that the wear rate increases from∼2.65×10^(-6)mm^(3)N^(-1)m^(-1)to∼10.56×10^(-6)mm^(3)N^(-1)m^(-1)in the temperature span RT to 400℃,following abrasive wear and flash temperature-induced oxidative wear during the friction.However,at the higher temperature of 600℃,further heating due to frictional heat leads to a softening of the wear surface,resulting in a maximum wear rate of∼20.99×10^(-6)mm^(3)N^(-1)m^(-1)under softness-driven abrasive wear as well as oxidative wear.Interestingly,the wear resistance at an even higher temperature of 750℃shows a paradoxical improvement of∼7.08×10^(-6)mm^(3)N^(-1)m^(-1),which is attributed to the formation of an oxide layer with a thickness of several microns,avoiding violent wear of BMG.The re-sults demonstrate the unreported outstanding high-temperature wear resistance of the Ir-Ta-Ni-Nb BMG,especially its excellent capability to resist wear at 750℃,leading to the promising applications of BMG in the fields of aerospace,metallurgy,and nuclear industries.展开更多
With the growing adoption of Electrical Vehicles(EVs),it is expected that a large number of on-board Li-ion batteries will be retired from EVs in the near future.Retired batteries will typically retain 80%of their ini...With the growing adoption of Electrical Vehicles(EVs),it is expected that a large number of on-board Li-ion batteries will be retired from EVs in the near future.Retired batteries will typically retain 80%of their initial capacities and can be recycled as second life batteries(SLBs).Although the capital costs of SLBs are much cheaper,their operational reliability is an important concern since used batteries may suffer from a higher failure rate.This paper aggregates brand new batteries and SLBs together to improve power system’s operating performance with renewable energy resources.In the context of a day-ahead and intra-day dispatch framework,a two-stage coordinated optimal scheduling method is proposed.Specifically,the energy cost of brand-new batteries and SLBs is calculated based on detailed battery degradation model,and the reliability of batteries is modeled based on the Weibull distribution.Moreover,Conditional value at risk(CVaR)criterion is applied to evaluate the risk induced by intermittent renewable power output,load demand variation and SLBs failure probability.Simulation tests demonstrate the effectiveness of the proposed method.展开更多
The simulation of internal-loop airlift reactors is challenging because complex meso-scale structures exist in different sections of the reactor, separated by the draft tube. This paper reports on the computational fl...The simulation of internal-loop airlift reactors is challenging because complex meso-scale structures exist in different sections of the reactor, separated by the draft tube. This paper reports on the computational fluid dynamics (CFD) simulation of internal-loop airlift reactors using a new drag model derived from the dual-bubble-size (DBS) model, an extended energy-minimization multi-scale (EMMS) approach for gas-liquid flows. Compared with the traditional Schiller-Naumann (S-N) correlation, the new model improves the simulation of gas holdup in the riser and downcomer significantly. In particular, gas holdup and circulation of two-phase flow can be modeled successfully using the new model, whereas traditional drag models such as the S-N correlation show an absence of gas in the downcomer. The simulation demonstrates the advantage and potential of this new model for internal-loop airlift reactors.展开更多
Until now, the onset velocity of circulating fluidization in liquid-solid fluidized beds has been defined by the turning point of the time required to empty a bed of particles as a function of the superfcial liquid ve...Until now, the onset velocity of circulating fluidization in liquid-solid fluidized beds has been defined by the turning point of the time required to empty a bed of particles as a function of the superfcial liquid velocity, and is reported to be only dependent on the liquid and particle properties. This study presents a new approach to calculate the onset velocity using CFD-DEM simulation of the particle residence time distribution (RTD). The onset velocity is identified from the intersection of the fitted lines of the particle mean residence time as a function of superficial liquid velocity. Our results are in reasonable agreement with experimental data. The simulation indicates that the onset velocity is infuenced by the density and size of particles and weakly affected by riser height and diameter, A power-law function is proposed to correlate the mean particle residence time with the superficial liquid velocity. The collisional parameters have a minor effect on the mean residence time of particles and the onset velocity, but influence the particle RTD, showing some humps and trailing. The particle RTD is found to be related to the particle trajectories, which may indicate the complex flow structure and underlying mechanisms of the particle RTD.展开更多
A two-factor(23)orthogonal testwas conducted to investigate the effects of dietary myo-inositol(MI)on the osmoregulation and carbohydrate metabolism of euryhaline fish tilapia(Oreochromis niloticus)under sustained hyp...A two-factor(23)orthogonal testwas conducted to investigate the effects of dietary myo-inositol(MI)on the osmoregulation and carbohydrate metabolism of euryhaline fish tilapia(Oreochromis niloticus)under sustained hypertonic stress(20 practical salinity units[psu]).6 diets containing either normal carbohydrate(NC,30%)or high carbohydrate(HC,45%)levels,with 3 levels(0,400 and 1,200 mg/kg diet)of MI,respectively,were fed to 540 fish under 20 psu for 8 weeks.Dietary MI supplementation significantly improved growth performance and crude protein content of whole fish,and decreased the content of crude lipid of whole fish(P<0.05).Curled,disordered gill lamella and cracked gill filament cartilage were observed in the gill of fish fed diets without MI supplementation.The ion transport capacity in gill was significantly improved in the 1,200 mg/kg MI supplementation groups compared with the 0 mg/kg MI groups(P<0.05).Moreover,the contents of Na^(+),K^(+),Cl^(-)in serum weremarkedly reduced with the dietary MI supplementation(P<0.05).The fish fed 1,200 mg/kg MI supplementation had the highest MI content in the gills and the lowest MI content in the serum(P<0.05).Additionally,the fish fed with 1,200 mg/kg MI supplementation had the highest MI synthesis capacity in gills and brain(P<0.05).Dietary MI markedly promoted the ability of carbohydrate metabolism in liver(P<0.05).Moreover,fish in the 1,200 mg/kg MI groups had the highest antioxidant capacity(P<0.05).This study indicated that high dietary carbohydrate would intensify stress,and impair the ability of osmoregulation in tilapia under a long-term hypersaline exposure.The supplementation of MI at 1,200 mg/kg in the high carbohydrate diet could promote carbohydrate utilization and improve the osmoregulation capacity of tilapia under long-term hypertonic stress.展开更多
Hydroxyapatite(HA)bioceramics have garnered considerable attention owing to their applications in the field of bone repair and excellent biocompatibility.Compared to extrusion-based 3D printing,projection-based 3D pri...Hydroxyapatite(HA)bioceramics have garnered considerable attention owing to their applications in the field of bone repair and excellent biocompatibility.Compared to extrusion-based 3D printing,projection-based 3D print-ing(3DPP)can fabricate parts with complex geometry,high accuracy,and efficiency,which is very promising for bioceramic scaffolds.However,conventional 3DPP using a paste with low viscosity will cause severe shrinkage of the parts after sintering,which makes it unsuitable for bioceramic scaffolds,and a system investigation of the printing process remains insufficient.In this study,we proposed a 3DPP device suitable for bioceramic scaffolds and investigated the additive manufacturing of HA scaffolds.Ceramic paste properties and process parameters of curing,debinding,and sintering were initially examined.The mechanical properties,shrinkage,and biocompati-bility in vitro of the sintered samples were further investigated.The obtained results indicate that HA bioceramics with uniform morphology,complex structure,and high accuracy can be manufactured using the 3DPP equip-ment.HA scaffolds have the mechanical strength of human cancellous bone,while HA scaffolds cultured with osteoblast precursor cells possess strong biocompatibility and can promote osteoblast adhesion,proliferation,and differentiation.These results suggest a promising application of the 3DPP technique in the preparation of bioceramic scaffolds,and the HA scaffolds fabricated using the 3DPP technique exhibit promising potential in fulfilling a constructive role in the biomedical field of human bone regeneration repair.展开更多
基金the National Natural Science Foundation of China(21978128,91934302)the State Key Laboratory of Materials-oriented Chemical Engineering(ZK202006)is acknowledged.
文摘Acetylene is produced from the reaction between calcium carbide(CaC_(2))and water,while the production of CaC_(2) generates significant amount of carbon dioxide not only because it is an energy-intensive process but also the raw material for CaC_(2) synthesis is from coal.Here,a comprehensive biomass-to-acetylene process was constructed that integrated several units including biomass pyrolysis,oxygen-thermal CaC_(2) fabrication and calcium looping.For comparison,a coal-to-acetylene process was also established by using coal as feedstock.The carbon efficiency,energy efficiency and environmental impacts of the bio-based calcium carbide acetylene(BCCA)and coal-based calcium carbide acetylene(CCCA)processes were systematically analyzed.Moreover,the environmental impacts were further evaluated by applying thermal integration at system level and energy substitution in CaC_(2) furnace.Even though the BCCA process showed lower carbon efficiency and energy efficiency than that of the CCCA process,life cycle assessment demonstrated the BCCA(1.873 kgCO_(2eq) kg-prod^(-1))a lower carbon footprint process which is 0.366 kgCO_(2eq) kg-prod^(-1) lower compared to the CCCA process.With sustainable energy(biomass power)substitution in CaC_(2) furnace,an even lower GWP value of 1.377 kgCO_(2eq) kg-prod^(-1) can be achieved in BCCA process.This work performed a systematic analysis on integrating biomass into industrial acetylene production,and revealed the positive role of biomass as raw material(carbon)and energy supplier.
基金support from the National Natural Science Foundation of China(21978128,91934302)partial support from the State Key Laboratory of Materials-oriented Chemical Engineering(ZK202006)also acknowledged.Additionallysupported by the“Cultivation Program for The Excellent Doctoral Dissertation of Nanjing Tech University(3800124701)”.
文摘In the carbonate industry,deep decarbonization strategies are necessary to effectively remediate CO_(2).These strategies mainly include both sustainable energy supplies and the conversion of CO_(2)in downstream processes.This study developed a coupled process of biomass chemical looping H2 production and reductive calcination of CaCO_(3).Firstly,a mass and energy balance of the coupled process was established in Aspen Plus.Following this,process optimization and energy integration were implemented to provide optimized operation conditions.Lastly,a life cycle assessment was carried out to assess the carbon footprint of the coupled process.Results reveal that the decomposition temperature of CaCO_(3)in an H_(2)atmosphere can be reduced to 780℃(generally around 900℃),and the conversion of CO_(2)from CaCO_(3)decomposition reached 81.33%with an H2:CO ratio of 2.49 in gaseous products.By optimizing systemic energy through heat integration,an energy efficiency of 86.30%was achieved.Additionally,the carbon footprint analysis revealed that the process with energy integration had a low global warming potential(GWP)of-2.624 kg·kg^(-1)(CO_(2)/CaO).Conclusively,this work performed a systematic analysis of introducing biomass-derived H_(2)into CaCO_(3)calcination and demonstrated the positive role of reductive calcination using green H_(2)in mitigating CO_(2)emissions within the carbonate industry.
基金National Natural Science Foundation of China,Grant/Award Number:52071217。
文摘Development of an electrocatalyst that is cheap and has good properties to replace conventional noble metals is important for H_(2) applications.In this study,dealloying of an amorphous Ti_(37)Cu_(60)Ru_(3) alloy was performed to prepare a freestanding nanostructured hydrogen evolution reaction(HER)catalyst.The effect of dealloying and addition of Ru to TiCu alloys on the microstructure and HER properties under alkaline conditions was investigated.3 at.%Ru addition in Ti_(40)Cu_(60) decreases the overpotential to reach a current density of 10mA cm^(-2) and Tafel slope of the dealloyed samples to 35 and 34mV dec−1.The improvement of electrocatalytic properties was attributed to the formation of a nanostructure and the modification of the electronic structure of the catalyst.First-principles calculations based on density function theory indicate that Ru decreases the Gibbs free energy of water dissociation.This work presents a method to prepare an efficient electrocatalyst via dealloying of amorphous alloys.
基金finance support of the Ministry of Science and Technology (State Key Research Plan, 2013BAC12B00)the National Natural Science Foundation of China (21336004 and 51254002)
文摘The issues of reducing CO_2 levels in the atmo-sphere, sustainably utilizing natural mineral resources,and dealing with indus trial waste offer challenging opportunities for sustainable development in energy and the environment. The latest advances in CO_2 mineralization technology involving natural minerals and industrial waste are summarized in this paper, with great emphasis on the advancement of fundamental science, economic evaluation, and engineering applications. We discuss several lead-ing large-scale CO_2 mineralization methodologies from a techn ical and engineering-science perspective. For each technology option, we give an overview of the technical parameters, reaction pathway, reactivity, procedural scheme, and laboratorial and pilot devices. Furthermore, we present a discussion of each technology based on experimental results and the literature. Finally, current gaps in knowledge are identified in the conclusion, and an overview of the challenges and opportunities for future research in this field is provided.
基金supported part by the National Natural Science Foundation of China(61601252,61801254)Public Technology Projects of Zhejiang Province(LG-G18F020007)+1 种基金Zhejiang Provincial Natural Science Foundation of China(LY20F020008,LY18F020011,LY20F010004)K.C.Wong Magna Fund in Ningbo University。
文摘With the emerging diverse applications in data centers,the demands on quality of service in data centers also become diverse,such as high throughput of elephant flows and low latency of deadline-sensitive flows.However,traditional TCPs are ill-suited to such situations and always result in the inefficiency(e.g.missing the flow deadline,inevitable throughput collapse)of data transfers.This further degrades the user-perceived quality of service(QoS)in data centers.To reduce the flow completion time of mice and deadline-sensitive flows along with promoting the throughput of elephant flows,an efficient and deadline-aware priority-driven congestion control(PCC)protocol,which grants mice and deadline-sensitive flows the highest priority,is proposed in this paper.Specifically,PCC computes the priority of different flows according to the size of transmitted data,the remaining data volume,and the flows’deadline.Then PCC adjusts the congestion window according to the flow priority and the degree of network congestion.Furthermore,switches in data centers control the input/output of packets based on the flow priority and the queue length.Different from existing TCPs,to speed up the data transfers of mice and deadline-sensitive flows,PCC provides an effective method to compute and encode the flow priority explicitly.According to the flow priority,switches can manage packets efficiently and ensure the data transfers of high priority flows through a weighted priority scheduling with minor modification.The experimental results prove that PCC can improve the data transfer performance of mice and deadline-sensitive flows while guaranting the throughput of elephant flows.
基金supported by the Key Basic and Applied Research Program of Guangdong Province,China(Grant No.2019B030302010)the NSF of China(Grant Nos.52122105,51971150,51901243)+1 种基金the Science and Technology Innovation Commission Shenzhen(Grants No.RCJC20221008092730037 and 20220804091920001)the National Key Research and Development Program of China(Grant No.2018YFA0703605).
文摘Metallic glasses(MGs)possess exceptional properties,but their properties consistently deteriorate over time,thereby resulting in increased complexity in processing.It thus poses a formidable challenge to the forming of long-term aged MGs.Here,we report ultrasonic vibration(UV)loading can lead to large plas-ticity and strong rejuvenation in significantly aged MGs within 1 s.A large UV-induced plasticity(UVIP)of 80%height reduction can be achieved in LaNiAl MG samples aged at 85%of its glass transition tem-perature(0.85 T_(g))for a duration of up to 1 month.The energy threshold required for UVIP monotonously increases with aging time.After the UV loading process,the aged samples show strong rejuvenation,with the relaxation enthalpy even surpassing that of as-cast samples.These findings suggest that UV loading is an effective technique for forming and rejuvenating aged MGs simultaneously,providing an alterna-tive avenue to explore the interplay between the property and microstructures as well as expanding the application prospects of MGs.
基金supported by the National Natural Science Foundation of China(Grant Nos.:22278070,21978047)
文摘Utilizing ionic liquid(IL)-water mixtures as selective extraction solvents for raw materials from natural sources represents an efficacious approach;however,elucidating the underlying mechanisms inherent in various types of IL-aqueous solutions continues to pose a significant challenge.In this study,molecular dynamics simulations and density functional theory calculations are employed to illuminate the influence of the functional anion within ILs and the water content on the solvation mechanism and phase separation phenomena observed during the extraction of camptothecin(CPT)using aqueous IL solutions.The simulation results show that the anions in ILs preferentially dissolve CPT through hydrogen bonding at low water concentrations.As the water concentration increases,the hydrophobic IL binds more tightly to CPT,enabling the water to self-aggregate.The anions in hydrophilic IL form hydrogen bonds with water instead,further enhancing the dissolution of CPT.This work reveals the mechanism of phase separation and solvation of different types of IL aqueous solutions,which is helpful in developing new drug extraction and purification technologies.
基金financially supported by the National Key Research and Development Program of China(Grant No.2018YFA0703605)the Key Basic and Applied Research Pro-gram of Guangdong Province,China(Grant No.2019B030302010)+1 种基金the NSF of China(Grant No.52122105,51971150)the Science and Technology Innovation Commission Shenzhen(Grants No.RCJC20221008092730037,20220804091920001)。
文摘Wear resistance is a critical consideration in engineering applications.In this study,we demonstrated an Ir-Ta-Ni-Nb bulk metallic glass(BMG)with outstanding high-temperature wear resistance and revealed its promising applications in extreme environments.The wear behavior and mechanism were systemati-cally investigated from room temperature(RT)to 750℃.The results show that the wear rate increases from∼2.65×10^(-6)mm^(3)N^(-1)m^(-1)to∼10.56×10^(-6)mm^(3)N^(-1)m^(-1)in the temperature span RT to 400℃,following abrasive wear and flash temperature-induced oxidative wear during the friction.However,at the higher temperature of 600℃,further heating due to frictional heat leads to a softening of the wear surface,resulting in a maximum wear rate of∼20.99×10^(-6)mm^(3)N^(-1)m^(-1)under softness-driven abrasive wear as well as oxidative wear.Interestingly,the wear resistance at an even higher temperature of 750℃shows a paradoxical improvement of∼7.08×10^(-6)mm^(3)N^(-1)m^(-1),which is attributed to the formation of an oxide layer with a thickness of several microns,avoiding violent wear of BMG.The re-sults demonstrate the unreported outstanding high-temperature wear resistance of the Ir-Ta-Ni-Nb BMG,especially its excellent capability to resist wear at 750℃,leading to the promising applications of BMG in the fields of aerospace,metallurgy,and nuclear industries.
基金supported in part by the National Natural Science Foundation of China (NO.52278003 and NO.72171026)in part by the National Natural Science Foundation of Hunan province (NO.21A0217)。
文摘With the growing adoption of Electrical Vehicles(EVs),it is expected that a large number of on-board Li-ion batteries will be retired from EVs in the near future.Retired batteries will typically retain 80%of their initial capacities and can be recycled as second life batteries(SLBs).Although the capital costs of SLBs are much cheaper,their operational reliability is an important concern since used batteries may suffer from a higher failure rate.This paper aggregates brand new batteries and SLBs together to improve power system’s operating performance with renewable energy resources.In the context of a day-ahead and intra-day dispatch framework,a two-stage coordinated optimal scheduling method is proposed.Specifically,the energy cost of brand-new batteries and SLBs is calculated based on detailed battery degradation model,and the reliability of batteries is modeled based on the Weibull distribution.Moreover,Conditional value at risk(CVaR)criterion is applied to evaluate the risk induced by intermittent renewable power output,load demand variation and SLBs failure probability.Simulation tests demonstrate the effectiveness of the proposed method.
基金the National Natural Science Foundation of China(21222603,U1162107)Ministry of Science and Technology of China(2013BAC12B01)the Strategic Priority Research Program of Chinese Academy of Sciences(XDA07080301) for their long-term support
文摘The simulation of internal-loop airlift reactors is challenging because complex meso-scale structures exist in different sections of the reactor, separated by the draft tube. This paper reports on the computational fluid dynamics (CFD) simulation of internal-loop airlift reactors using a new drag model derived from the dual-bubble-size (DBS) model, an extended energy-minimization multi-scale (EMMS) approach for gas-liquid flows. Compared with the traditional Schiller-Naumann (S-N) correlation, the new model improves the simulation of gas holdup in the riser and downcomer significantly. In particular, gas holdup and circulation of two-phase flow can be modeled successfully using the new model, whereas traditional drag models such as the S-N correlation show an absence of gas in the downcomer. The simulation demonstrates the advantage and potential of this new model for internal-loop airlift reactors.
基金long term support from the National Natural Science Foundation of China(Grant Nos.21222603 and 91434121)the Ministry of Science and Technology of China(Grant No.2013BAC12B01)the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDA07080301)
文摘Until now, the onset velocity of circulating fluidization in liquid-solid fluidized beds has been defined by the turning point of the time required to empty a bed of particles as a function of the superfcial liquid velocity, and is reported to be only dependent on the liquid and particle properties. This study presents a new approach to calculate the onset velocity using CFD-DEM simulation of the particle residence time distribution (RTD). The onset velocity is identified from the intersection of the fitted lines of the particle mean residence time as a function of superficial liquid velocity. Our results are in reasonable agreement with experimental data. The simulation indicates that the onset velocity is infuenced by the density and size of particles and weakly affected by riser height and diameter, A power-law function is proposed to correlate the mean particle residence time with the superficial liquid velocity. The collisional parameters have a minor effect on the mean residence time of particles and the onset velocity, but influence the particle RTD, showing some humps and trailing. The particle RTD is found to be related to the particle trajectories, which may indicate the complex flow structure and underlying mechanisms of the particle RTD.
基金grants from the National Natural Science Foundation of China(No.32172946)China Postdoctoral Science Foundation(2018 M630418)the Fundamental Research Funds for the Central Universities,ECNU and China Agriculture Research System-46(CARS-46).
文摘A two-factor(23)orthogonal testwas conducted to investigate the effects of dietary myo-inositol(MI)on the osmoregulation and carbohydrate metabolism of euryhaline fish tilapia(Oreochromis niloticus)under sustained hypertonic stress(20 practical salinity units[psu]).6 diets containing either normal carbohydrate(NC,30%)or high carbohydrate(HC,45%)levels,with 3 levels(0,400 and 1,200 mg/kg diet)of MI,respectively,were fed to 540 fish under 20 psu for 8 weeks.Dietary MI supplementation significantly improved growth performance and crude protein content of whole fish,and decreased the content of crude lipid of whole fish(P<0.05).Curled,disordered gill lamella and cracked gill filament cartilage were observed in the gill of fish fed diets without MI supplementation.The ion transport capacity in gill was significantly improved in the 1,200 mg/kg MI supplementation groups compared with the 0 mg/kg MI groups(P<0.05).Moreover,the contents of Na^(+),K^(+),Cl^(-)in serum weremarkedly reduced with the dietary MI supplementation(P<0.05).The fish fed 1,200 mg/kg MI supplementation had the highest MI content in the gills and the lowest MI content in the serum(P<0.05).Additionally,the fish fed with 1,200 mg/kg MI supplementation had the highest MI synthesis capacity in gills and brain(P<0.05).Dietary MI markedly promoted the ability of carbohydrate metabolism in liver(P<0.05).Moreover,fish in the 1,200 mg/kg MI groups had the highest antioxidant capacity(P<0.05).This study indicated that high dietary carbohydrate would intensify stress,and impair the ability of osmoregulation in tilapia under a long-term hypersaline exposure.The supplementation of MI at 1,200 mg/kg in the high carbohydrate diet could promote carbohydrate utilization and improve the osmoregulation capacity of tilapia under long-term hypertonic stress.
基金supported by National Natural Science Foundation of China(Grant Nos.51805475,81827804)Zhejiang Provincial Natural Science Foundation of China(Grant No.LY22E050011)+1 种基金Open Founda-tion of the State Key Laboratory of Fluid Power and Mechatronic Sys-tems(Grant No.GZKF-202102)Jiangsu Key Laboratory of 3D Print-ing Equipment and Manufacturing(Grant No.3DL202105).
文摘Hydroxyapatite(HA)bioceramics have garnered considerable attention owing to their applications in the field of bone repair and excellent biocompatibility.Compared to extrusion-based 3D printing,projection-based 3D print-ing(3DPP)can fabricate parts with complex geometry,high accuracy,and efficiency,which is very promising for bioceramic scaffolds.However,conventional 3DPP using a paste with low viscosity will cause severe shrinkage of the parts after sintering,which makes it unsuitable for bioceramic scaffolds,and a system investigation of the printing process remains insufficient.In this study,we proposed a 3DPP device suitable for bioceramic scaffolds and investigated the additive manufacturing of HA scaffolds.Ceramic paste properties and process parameters of curing,debinding,and sintering were initially examined.The mechanical properties,shrinkage,and biocompati-bility in vitro of the sintered samples were further investigated.The obtained results indicate that HA bioceramics with uniform morphology,complex structure,and high accuracy can be manufactured using the 3DPP equip-ment.HA scaffolds have the mechanical strength of human cancellous bone,while HA scaffolds cultured with osteoblast precursor cells possess strong biocompatibility and can promote osteoblast adhesion,proliferation,and differentiation.These results suggest a promising application of the 3DPP technique in the preparation of bioceramic scaffolds,and the HA scaffolds fabricated using the 3DPP technique exhibit promising potential in fulfilling a constructive role in the biomedical field of human bone regeneration repair.