In this study,femtosecond pulsed laser processing was applied to the magnesium alloy,followed by in situ growth of Mg-Al layered double hydroxides(LDHs),and finally modification with low surface energy materials to pr...In this study,femtosecond pulsed laser processing was applied to the magnesium alloy,followed by in situ growth of Mg-Al layered double hydroxides(LDHs),and finally modification with low surface energy materials to prepare a biomimetic of centipede-like superhydrophobic composite coating.The resulting biomimetic coating features a dual-scale structure,comprising a micron-scale laser-etched array and nano-scale LDH sheets,which together create a complex hierarchical architecture.The multistage bionic superhydrophobic coating exhibits exceptional corrosion resistance,with a reduction in corrosion current density by approximately five orders of magnitude compared to the bare magnesium alloy substrate.This remarkable corrosion resistance is attributed to the synergistic effects of the superhydrophobicity with a contact angle(CA)of 154.60°,the densification of the surface LDH nanosheets,and the NO_(3)^(-) exchange capacity.Additionally,compared to untreated AZ91D alloy,the biomimetic coating prolongs ice formation time by 250% at-40℃ and withstands multiple cycles of sandpaper abrasion and repeated tape peeling tests.Furthermore,it demonstrates excellent self-cleaning and anti-fouling properties,as confirmed by dye immersion and dust contamination tests.The construction of the multi-level bionic structured coating not only holds significant practical potential for metal protection but also provides valuable insights into the application of formed LDH materials in functional bionic coating engineering.展开更多
[Objectives]Farmland ginseng cultivation,as a sustainable alternative to traditional forest-clearing ginseng planting,requires systematic evaluation of soil optimization strategies.This study aimed to quantify the lin...[Objectives]Farmland ginseng cultivation,as a sustainable alternative to traditional forest-clearing ginseng planting,requires systematic evaluation of soil optimization strategies.This study aimed to quantify the linkage between soil improvement outcomes and ginseng(Panax ginseng)yield across five regions in Yanbian Korean Autonomous Prefecture.[Methods]Soil improvement trials were conducted using farmland soils,with forest soils as the baseline.Soil nutrient contents were measured via soil agrochemical analysis method using a continuous flow analyzer.Statistical approaches,including significance tests,correlation analysis,and regression analysis,were applied to identify key factors influencing yield.[Results]Ginseng yield exhibited a significant positive correlation with organic matter content and available phosphorus,but a negative correlation with electrical conductivity,ammonium nitrogen,and available potassium.Wangqing and Liucai regions achieved post-improvement yields equivalent to 94%and 88%of forest soil yields,respectively,demonstrating the highest soil similarity to forest ecosystems.[Conclusions]Region-specific soil improvement protocols in Wangqing and Liucai show high replicability and efficacy.These strategies can serve as benchmarks for sustainable farmland ginseng cultivation,minimizing ecological disruption while maintaining productivity.展开更多
Carbon fibers(CFs)with notable comprehensive properties,such as light weight,high specific strength,and stiffness,have garnered considerable interest in both academic and industrial fields due to their diverse and adv...Carbon fibers(CFs)with notable comprehensive properties,such as light weight,high specific strength,and stiffness,have garnered considerable interest in both academic and industrial fields due to their diverse and advanced applications.However,the commonly utilized precursors,such as polyacrylonitrile and pitch,exhibit a lack of environmental sustainability,and their costs are heavily reliant on fluctuating petroleum prices.To meet the substantial market demand for CFs,significant efforts have been made to develop cost-effective and sustainable CFs derived from biomass.Lignin,the most abundant polyphenolic compound in nature,is emerging as a promising precursor which is well-suited for the production of CFs due to its renewable nature,low cost,high carbon content,and aromatic structures.Nevertheless,the majority of lignin raw materials are currently derived from pulping and biorefining industrial by-products,which are diverse and heterogeneous in nature,restricting the industrialization of lignin-derived CFs.This review classifies fossil-derived and biomass-derived CFs,starting from the sources and chemical structures of raw lignin,and outlines the preparation methods linked to the performance of lignin-derived CFs.A comprehensive discussion is presented on the relationship between the structural characteristics of lignin,spinning preparation,and structure-morphology-property of ligninderived CFs.Additionally,the potential applications of these materials in various domains,including energy,catalysis,composites,and other advanced products,are also described with the objective of spotlighting the unique merits of lignin.Finally,the current challenges faced and future prospects for the advancement of lignin-derived CFs are proposed.展开更多
Solar-driven interfacial evaporation is one of the most attractive approaches to addressing the global freshwater shortage.However,achieving an integrated high evaporation rate,salt harvesting,and multifunctionality i...Solar-driven interfacial evaporation is one of the most attractive approaches to addressing the global freshwater shortage.However,achieving an integrated high evaporation rate,salt harvesting,and multifunctionality in evaporator is still a crucial challenge.Here,a novel composite membrane with biomimetic micronanostructured superhydrophobic surface is designed via ultrafast laser etching technology.Attractively,the double-transition-metal(V_(1/2)Mo_(1/2))_(2)CT_(x)MXene nanomaterials as a photothermal layer,exhibiting the enhanced photothermal conversion performance due to elevated joint densities of states,which enables high populations of photoexcited carrier relaxation and heat release,provides a new insight into the photothermal conversion mechanism for multiple principal element MXene.Hence,the(V_(1/2)Mo_(1/2))_(2)CT_(x)MXene-200 composite membrane can achieve a high evaporation rate of 2.23 kg m^(−2)h^(−1)under one sun,owing to the enhanced“light trap”effect,photothermal conversion,and high-throughput water transfer.Synergetically,the membrane can induce the directed precipitation of salt at the membrane edge,thus enabling salt harvesting for recycling and zero-emission of brine water.Moreover,the composite membrane is endowed with excellent multifunctionality of anti-/de-icing,anti-fouling,and antibacterial,overcoming the disadvantage that versatility is difficult to be compatible.Therefore,the evaporator and the promising strategy hold great potential for the practical application of solar evaporation.展开更多
Multifunctional architecture with intriguing structural design is highly desired for realizing the promising performances in wearable sensors and flexible energy storage devices.Cellulose nanofiber(CNF)is employed for...Multifunctional architecture with intriguing structural design is highly desired for realizing the promising performances in wearable sensors and flexible energy storage devices.Cellulose nanofiber(CNF)is employed for assisting in building conductive,hyperelastic,and ultralight Ti_(3)C_(2)T_(x)MXene hybrid aerogels with oriented tracheid-like texture.The biomimetic hybrid aerogels are constructed by a facile bidirectional freezing strategy with CNF,carbon nanotube(CNT),and MXene based on synergistic electrostatic interaction and hydrogen bonding.Entangled CNF and CNT“mortars”bonded with MXene“bricks”of the tracheid structure produce good interfacial binding,and superior mechanical strength(up to 80%compressibility and extraordinary fatigue resistance of 1000 cycles at 50%strain).Benefiting from the biomimetic texture,CNF/CNT/MXene aerogel shows ultralow density of 7.48 mg cm^(-3)and excellent electrical conductivity(~2400 S m^(-1)).Used as pressure sensors,such aerogels exhibit appealing sensitivity performance with the linear sensitivity up to 817.3 kPa^(-1),which affords their application in monitoring body surface information and detecting human motion.Furthermore,the aerogels can also act as electrode materials of compressive solid-state supercapacitors that reveal satisfactory electrochemical performance(849.2 mF cm^(-2)at 0.8 mA cm^(-2))and superior long cycle compression performance(88%after 10,000 cycles at a compressive strain of 30%).展开更多
In-situ pressure-preserved coring(IPP-Coring)is considered to be the most reliable and efficient method for the identification of the scale of oil and gas resources.During IPP-Coring,because the rotation behavior of t...In-situ pressure-preserved coring(IPP-Coring)is considered to be the most reliable and efficient method for the identification of the scale of oil and gas resources.During IPP-Coring,because the rotation behavior of the pressure controller valve cover in different medium environments is unclear,interference between the valve cover and inner pipe may occur and negatively affect the IPP-Coring success rate.To address this issue,we conducted a series of indoor experiments employing a high-speed camera to gain greater insights into the valve cover rotation behavior in different medium environments,e.g.,air,water,and simulated drilling fluids.The results indicated that the variation in the valve cover rotation angle in the air and fluid environments can be described by a one-phase exponential decay function with a constant time parameter and by biphasic dose response function,respectively.The rotation behavior in the fluid environments exhibited distinct elastic and gravitational acceleration zones.In the fluid environments,the density clearly impacted the valve cover closing time and rotation behavior,whereas the effect of viscosity was very slight.This can be attributed to the negligible influence of the fluid viscosity on the drag coefficient found in this study;meanwhile,the density can increase the buoyancy and the time period during which the valve cover experienced a high drag coefficient.Considering these results,control schemes for the valve cover rotation behavior during IPP-Coring were proposed for different layers and geological conditions in which the different drilling fluids should be used,e.g.,the use of a high-density valve cover in high-pore pressure layers.展开更多
The paper presents a novel control design,which is based on the idea of active disturbance rejection control(ADRC),for a kind of flexible aerocraft whose contolled variable cannot be measured directly.Since the origin...The paper presents a novel control design,which is based on the idea of active disturbance rejection control(ADRC),for a kind of flexible aerocraft whose contolled variable cannot be measured directly.Since the original frame of ADRC can-not be directly applied,the paper puts forward a new extended state observer(ESO)and the corresponding ADRC law.In order to assign the poles of the closed loop system to ideal positions such that the vibration can be quickly suppressed,an elastic damping term is added into feedback law.The advantages of the new ESO for fectively estimating both the rigid mode and elastic mode from the measurements are discussed.Moreover,the analysis on the stabiliy.the relative stability and the steady state of the closed-loop system is given.Finally,the efectiveness and robustness of the proposed ADRC are verified by simulations.展开更多
Lignin is the most abundant aromatic compound found in nature.The rich functional groups of lignin are responsible for its antibacterial,antioxidant,anti-ultraviolet,and biocompatible properties.As modified lignin has...Lignin is the most abundant aromatic compound found in nature.The rich functional groups of lignin are responsible for its antibacterial,antioxidant,anti-ultraviolet,and biocompatible properties.As modified lignin has a higher molecular weight,water solubility,and better surface activity,it is a good candidate for the construction of new biological materials.Ligninbased hydrogels are a type of functional materials with broad application prospects in the biomedical field.This review aimed to introduce the biological properties of lignin and the application of lignin-based hydrogels in the biological field.展开更多
To provide a more accurate evaluation of the scale of deep underground resources,a new pressure coring system was carefully developed and its strength and safety of the engineering were verified by theoretical analyse...To provide a more accurate evaluation of the scale of deep underground resources,a new pressure coring system was carefully developed and its strength and safety of the engineering were verified by theoretical analyses and numerical simulation.The designed pressure coring system can obtain cores with length of 3 m and diameter of 50 mm at 70 MPa.The results of the ball-drop operation experiment demonstrate that differential motion assembly can effectively cut a safety pin by applying a tensile force of 4852 N,and it can lift the core tube through the center pole to complete a series of mechanical actions to seal the pressure.Additionally,by maintaining pressures at 70 MPa for 30 min,the pressure sealing capacity of the system was proven.Furthermore,a core sample with a diameter of 50 mm was obtained through a core drilling experiment and the coring performance of the pressure coring system was verified.This study can not only enrich the existing onshore coring technology but also provide a theoretical guide and design criteria for the development of similar pressure coring systems to meet the demand for deeper underground exploration.展开更多
Lignin,the second most abundant bio-renewable polymer in the world after cellulose,is widely used in industrial production.In recent years,nanoparticles have attracted increasing attention due to their excellent prope...Lignin,the second most abundant bio-renewable polymer in the world after cellulose,is widely used in industrial production.In recent years,nanoparticles have attracted increasing attention due to their excellent properties.Therefore,the preparation of lignin nanoparticles to obtain valueadded products is an effective way to utilize their potential completely.This article describes the preparation methods of micro/nanosized lignin with different sizes and shapes,and provides a detailed introduction to their applications in biomedicine.展开更多
Battery-grade lithium carbonate(Li_(2)CO_(3))with a purity of higher than 99.5 wt%is of great importance as a high value-added lithium salt.However,influences of different reaction systems and process control on produ...Battery-grade lithium carbonate(Li_(2)CO_(3))with a purity of higher than 99.5 wt%is of great importance as a high value-added lithium salt.However,influences of different reaction systems and process control on product purity remain unclear.Herein,a membrane dispersion microreactor was used to enhance the mass transfer of preparation and purification processes in homogeneous and heterogeneous system.Synthetic systems of Na_(2)CO_(3)–LiCl,NH_(4)HCO_(3)–LiCl,and NH_(3)·H_(2)O−CO_(2)−LiCl,CO_(2)purification based on carbonation and decomposition were adopted.The Li_(2)CO_(3)purity was increased by the improvement of mixing performance.The carbonation time was reduced by 62.5%and 58.3%for the NH_(3)·H_(2)O−CO_(2)and CO_(2)purification systems,respectively.In the two ammonia-based systems,Li_(2)CO_(3)particles with a purity of 99.7–99.8 wt%were one-step prepared with a size of 3–5μm,which also met the requirement of the battery-grade standard.The purity was further increased to 99.9 wt%by CO_(2)purification and LiHCO_(3)decomposition.The investigation could provide a feasible alternative for the controllable preparation of battery-grade Li_(2)CO_(3)in one or multiple steps.展开更多
Basil(Ocimum basilicum),an edible and medicinal plant with high nutritional value and therapeutic efficacy,was used as a potential source of total flavonoids in this study.Heat reflux extractions were performed using ...Basil(Ocimum basilicum),an edible and medicinal plant with high nutritional value and therapeutic efficacy,was used as a potential source of total flavonoids in this study.Heat reflux extractions were performed using aqueous ethanol.The optimized extraction conditions of total flavonoids from O.basilicum were determined by Box-Behnken design with response surface methodology.Response surface plots showed that the optional four independent variables significantly influenced the extraction yield of total flavonoids.The extraction parameters for the highest total flavonoids yield were optimized as:extraction temperature of 79.74℃,ethanol concentration of 77.63%,ratio of liquid to material of 29.72:1(mL/g),and extraction time of 2.06 h.The average yield of total flavonoids under above optimum parameters was 42.61 mg of rutin equivalents per g of extract dry matter,which was in good agreement with the predicted value of 40.23 mg/g.These optimized conditions could be useful for the extraction of flavonoids from O.basilicum.展开更多
基金supported by the National Natural Science Foundation of China(No.52331004,U2106216)the Natural Science Foundation of Shandong Province(No.ZR2022ZD12)+2 种基金the Key R&D Program of Shandong Province,China(2023ZLGX05,2023CXGC010406)Key Program of Natural Science Foundation of Shandong Province of China(No.ZR2022ZD12,ZR2024ZD14)the Taishan Scholarship of Climbing Plan(No.tspd20230603)。
文摘In this study,femtosecond pulsed laser processing was applied to the magnesium alloy,followed by in situ growth of Mg-Al layered double hydroxides(LDHs),and finally modification with low surface energy materials to prepare a biomimetic of centipede-like superhydrophobic composite coating.The resulting biomimetic coating features a dual-scale structure,comprising a micron-scale laser-etched array and nano-scale LDH sheets,which together create a complex hierarchical architecture.The multistage bionic superhydrophobic coating exhibits exceptional corrosion resistance,with a reduction in corrosion current density by approximately five orders of magnitude compared to the bare magnesium alloy substrate.This remarkable corrosion resistance is attributed to the synergistic effects of the superhydrophobicity with a contact angle(CA)of 154.60°,the densification of the surface LDH nanosheets,and the NO_(3)^(-) exchange capacity.Additionally,compared to untreated AZ91D alloy,the biomimetic coating prolongs ice formation time by 250% at-40℃ and withstands multiple cycles of sandpaper abrasion and repeated tape peeling tests.Furthermore,it demonstrates excellent self-cleaning and anti-fouling properties,as confirmed by dye immersion and dust contamination tests.The construction of the multi-level bionic structured coating not only holds significant practical potential for metal protection but also provides valuable insights into the application of formed LDH materials in functional bionic coating engineering.
基金Supported by National Natural Science Foundation Cultivation Project of Lishui University(036/2024)Municipal-Level Project:Pathways for Establishing Low-carbon Pilot Counties(FGLS202210).
文摘[Objectives]Farmland ginseng cultivation,as a sustainable alternative to traditional forest-clearing ginseng planting,requires systematic evaluation of soil optimization strategies.This study aimed to quantify the linkage between soil improvement outcomes and ginseng(Panax ginseng)yield across five regions in Yanbian Korean Autonomous Prefecture.[Methods]Soil improvement trials were conducted using farmland soils,with forest soils as the baseline.Soil nutrient contents were measured via soil agrochemical analysis method using a continuous flow analyzer.Statistical approaches,including significance tests,correlation analysis,and regression analysis,were applied to identify key factors influencing yield.[Results]Ginseng yield exhibited a significant positive correlation with organic matter content and available phosphorus,but a negative correlation with electrical conductivity,ammonium nitrogen,and available potassium.Wangqing and Liucai regions achieved post-improvement yields equivalent to 94%and 88%of forest soil yields,respectively,demonstrating the highest soil similarity to forest ecosystems.[Conclusions]Region-specific soil improvement protocols in Wangqing and Liucai show high replicability and efficacy.These strategies can serve as benchmarks for sustainable farmland ginseng cultivation,minimizing ecological disruption while maintaining productivity.
基金National Natural Science Foundation of China,Grant/Award Numbers:32171717,32271814Natural Science Foundation of Tianjin Municipality,Grant/Award Numbers:24JCJQJC00030,22JCYBJC01560,23JCZDJC00630China Postdoctoral Science Foundation,Grant/Award Number:2023M740562。
文摘Carbon fibers(CFs)with notable comprehensive properties,such as light weight,high specific strength,and stiffness,have garnered considerable interest in both academic and industrial fields due to their diverse and advanced applications.However,the commonly utilized precursors,such as polyacrylonitrile and pitch,exhibit a lack of environmental sustainability,and their costs are heavily reliant on fluctuating petroleum prices.To meet the substantial market demand for CFs,significant efforts have been made to develop cost-effective and sustainable CFs derived from biomass.Lignin,the most abundant polyphenolic compound in nature,is emerging as a promising precursor which is well-suited for the production of CFs due to its renewable nature,low cost,high carbon content,and aromatic structures.Nevertheless,the majority of lignin raw materials are currently derived from pulping and biorefining industrial by-products,which are diverse and heterogeneous in nature,restricting the industrialization of lignin-derived CFs.This review classifies fossil-derived and biomass-derived CFs,starting from the sources and chemical structures of raw lignin,and outlines the preparation methods linked to the performance of lignin-derived CFs.A comprehensive discussion is presented on the relationship between the structural characteristics of lignin,spinning preparation,and structure-morphology-property of ligninderived CFs.Additionally,the potential applications of these materials in various domains,including energy,catalysis,composites,and other advanced products,are also described with the objective of spotlighting the unique merits of lignin.Finally,the current challenges faced and future prospects for the advancement of lignin-derived CFs are proposed.
基金supported by the National Natural Science Foundation of China(No.U2106216,52331004)the Natural Science Foundation of Shandong Province(No.ZR2022ZD12)+5 种基金the Key R&D Program of Shandong Province,China(2023ZLGX05,2023CXGC010406)the Taishan Scholarship of Climbing Plan(No.tspd20230603)the Fundamental Research Funds for the Central Universities(202461105)the China Postdoctoral Science Foundation(2023M732677)Shandong Province Postdoctoral Innovation Project(SDCX-ZG-202303086)Key Laboratory of Ocean Energy Utilization and Energy Conservation of Ministry of Education(LOEC-202309).
文摘Solar-driven interfacial evaporation is one of the most attractive approaches to addressing the global freshwater shortage.However,achieving an integrated high evaporation rate,salt harvesting,and multifunctionality in evaporator is still a crucial challenge.Here,a novel composite membrane with biomimetic micronanostructured superhydrophobic surface is designed via ultrafast laser etching technology.Attractively,the double-transition-metal(V_(1/2)Mo_(1/2))_(2)CT_(x)MXene nanomaterials as a photothermal layer,exhibiting the enhanced photothermal conversion performance due to elevated joint densities of states,which enables high populations of photoexcited carrier relaxation and heat release,provides a new insight into the photothermal conversion mechanism for multiple principal element MXene.Hence,the(V_(1/2)Mo_(1/2))_(2)CT_(x)MXene-200 composite membrane can achieve a high evaporation rate of 2.23 kg m^(−2)h^(−1)under one sun,owing to the enhanced“light trap”effect,photothermal conversion,and high-throughput water transfer.Synergetically,the membrane can induce the directed precipitation of salt at the membrane edge,thus enabling salt harvesting for recycling and zero-emission of brine water.Moreover,the composite membrane is endowed with excellent multifunctionality of anti-/de-icing,anti-fouling,and antibacterial,overcoming the disadvantage that versatility is difficult to be compatible.Therefore,the evaporator and the promising strategy hold great potential for the practical application of solar evaporation.
基金supported by the Project of Jinan City(202228044)National Natural Science Foundation of China(32071720,32271814)+1 种基金the China Postdoctoral Science Foundation(2021M702456)China Scholarship Council for supporting their PhD program。
文摘Multifunctional architecture with intriguing structural design is highly desired for realizing the promising performances in wearable sensors and flexible energy storage devices.Cellulose nanofiber(CNF)is employed for assisting in building conductive,hyperelastic,and ultralight Ti_(3)C_(2)T_(x)MXene hybrid aerogels with oriented tracheid-like texture.The biomimetic hybrid aerogels are constructed by a facile bidirectional freezing strategy with CNF,carbon nanotube(CNT),and MXene based on synergistic electrostatic interaction and hydrogen bonding.Entangled CNF and CNT“mortars”bonded with MXene“bricks”of the tracheid structure produce good interfacial binding,and superior mechanical strength(up to 80%compressibility and extraordinary fatigue resistance of 1000 cycles at 50%strain).Benefiting from the biomimetic texture,CNF/CNT/MXene aerogel shows ultralow density of 7.48 mg cm^(-3)and excellent electrical conductivity(~2400 S m^(-1)).Used as pressure sensors,such aerogels exhibit appealing sensitivity performance with the linear sensitivity up to 817.3 kPa^(-1),which affords their application in monitoring body surface information and detecting human motion.Furthermore,the aerogels can also act as electrode materials of compressive solid-state supercapacitors that reveal satisfactory electrochemical performance(849.2 mF cm^(-2)at 0.8 mA cm^(-2))and superior long cycle compression performance(88%after 10,000 cycles at a compressive strain of 30%).
基金The authors are grateful for the financial support from the National Natural Science Foundation of China(No.51827901&No.52274133)the Program for Guangdong Introducing Innovative and Enterpreneurial Teams(No.2019ZT08G315)the Shenzhen National Science Fund for Distinguished Young Scholars(RCJC20210706091948015).
文摘In-situ pressure-preserved coring(IPP-Coring)is considered to be the most reliable and efficient method for the identification of the scale of oil and gas resources.During IPP-Coring,because the rotation behavior of the pressure controller valve cover in different medium environments is unclear,interference between the valve cover and inner pipe may occur and negatively affect the IPP-Coring success rate.To address this issue,we conducted a series of indoor experiments employing a high-speed camera to gain greater insights into the valve cover rotation behavior in different medium environments,e.g.,air,water,and simulated drilling fluids.The results indicated that the variation in the valve cover rotation angle in the air and fluid environments can be described by a one-phase exponential decay function with a constant time parameter and by biphasic dose response function,respectively.The rotation behavior in the fluid environments exhibited distinct elastic and gravitational acceleration zones.In the fluid environments,the density clearly impacted the valve cover closing time and rotation behavior,whereas the effect of viscosity was very slight.This can be attributed to the negligible influence of the fluid viscosity on the drag coefficient found in this study;meanwhile,the density can increase the buoyancy and the time period during which the valve cover experienced a high drag coefficient.Considering these results,control schemes for the valve cover rotation behavior during IPP-Coring were proposed for different layers and geological conditions in which the different drilling fluids should be used,e.g.,the use of a high-density valve cover in high-pore pressure layers.
基金This work was supported by the National Key R&D Program of China(No.2018YFA0703800)the National Center for Mathematics and Interdisciplinary Sciences,Chinese Acad-emy of Sciences.
文摘The paper presents a novel control design,which is based on the idea of active disturbance rejection control(ADRC),for a kind of flexible aerocraft whose contolled variable cannot be measured directly.Since the original frame of ADRC can-not be directly applied,the paper puts forward a new extended state observer(ESO)and the corresponding ADRC law.In order to assign the poles of the closed loop system to ideal positions such that the vibration can be quickly suppressed,an elastic damping term is added into feedback law.The advantages of the new ESO for fectively estimating both the rigid mode and elastic mode from the measurements are discussed.Moreover,the analysis on the stabiliy.the relative stability and the steady state of the closed-loop system is given.Finally,the efectiveness and robustness of the proposed ADRC are verified by simulations.
基金the financial support from the National Natural Science Foundation of China(32171717)the Young Elite Scientists Sponsorship Program(YESS20200389).
文摘Lignin is the most abundant aromatic compound found in nature.The rich functional groups of lignin are responsible for its antibacterial,antioxidant,anti-ultraviolet,and biocompatible properties.As modified lignin has a higher molecular weight,water solubility,and better surface activity,it is a good candidate for the construction of new biological materials.Ligninbased hydrogels are a type of functional materials with broad application prospects in the biomedical field.This review aimed to introduce the biological properties of lignin and the application of lignin-based hydrogels in the biological field.
基金the Shenzhen National Science Fund for Distinguished Young Scholars(No.RCJC20210706091948015)National Science Fund for Distinguished Young Scholars(No.52225403)the National Natural Science Foundation of China(No.51827901).
文摘To provide a more accurate evaluation of the scale of deep underground resources,a new pressure coring system was carefully developed and its strength and safety of the engineering were verified by theoretical analyses and numerical simulation.The designed pressure coring system can obtain cores with length of 3 m and diameter of 50 mm at 70 MPa.The results of the ball-drop operation experiment demonstrate that differential motion assembly can effectively cut a safety pin by applying a tensile force of 4852 N,and it can lift the core tube through the center pole to complete a series of mechanical actions to seal the pressure.Additionally,by maintaining pressures at 70 MPa for 30 min,the pressure sealing capacity of the system was proven.Furthermore,a core sample with a diameter of 50 mm was obtained through a core drilling experiment and the coring performance of the pressure coring system was verified.This study can not only enrich the existing onshore coring technology but also provide a theoretical guide and design criteria for the development of similar pressure coring systems to meet the demand for deeper underground exploration.
基金The authors are grateful for the financial support from the National Natural Science Foundation of China(32071720)the Young Elite Scientists Sponsorship Program of Tianjin(TJSQNTJ-2017-19).
文摘Lignin,the second most abundant bio-renewable polymer in the world after cellulose,is widely used in industrial production.In recent years,nanoparticles have attracted increasing attention due to their excellent properties.Therefore,the preparation of lignin nanoparticles to obtain valueadded products is an effective way to utilize their potential completely.This article describes the preparation methods of micro/nanosized lignin with different sizes and shapes,and provides a detailed introduction to their applications in biomedicine.
基金the support from the National Natural Science Foundation of China(grant Nos.22278014,2227801521978008,21606008)the Innovation Fund of SIN0PEC Catalyst Co.Ltd-State Key Laboratory of Chemical Resource Engineering(grant No.36100000-22-ZC0607-0041).
文摘Battery-grade lithium carbonate(Li_(2)CO_(3))with a purity of higher than 99.5 wt%is of great importance as a high value-added lithium salt.However,influences of different reaction systems and process control on product purity remain unclear.Herein,a membrane dispersion microreactor was used to enhance the mass transfer of preparation and purification processes in homogeneous and heterogeneous system.Synthetic systems of Na_(2)CO_(3)–LiCl,NH_(4)HCO_(3)–LiCl,and NH_(3)·H_(2)O−CO_(2)−LiCl,CO_(2)purification based on carbonation and decomposition were adopted.The Li_(2)CO_(3)purity was increased by the improvement of mixing performance.The carbonation time was reduced by 62.5%and 58.3%for the NH_(3)·H_(2)O−CO_(2)and CO_(2)purification systems,respectively.In the two ammonia-based systems,Li_(2)CO_(3)particles with a purity of 99.7–99.8 wt%were one-step prepared with a size of 3–5μm,which also met the requirement of the battery-grade standard.The purity was further increased to 99.9 wt%by CO_(2)purification and LiHCO_(3)decomposition.The investigation could provide a feasible alternative for the controllable preparation of battery-grade Li_(2)CO_(3)in one or multiple steps.
基金This project was financially supported by National Natural Science Foundation of China(31260400)the foundations of Jiangsu Province Biomass Energy and Materials Laboratory in Institute of Chemical Industry of Forest Products,CAF(JSBEM201601)+2 种基金State Key Laboratory of Pulp&Paper Engineering(201611,201503)Jiangsu Provincial Key Laboratory of Pulp and Paper Science and Technology,Nanjing Forestry University(201531)P.R.China,Natural Science Foundation of Tianjin City(16JCQNJC05900)for financial support。
文摘Basil(Ocimum basilicum),an edible and medicinal plant with high nutritional value and therapeutic efficacy,was used as a potential source of total flavonoids in this study.Heat reflux extractions were performed using aqueous ethanol.The optimized extraction conditions of total flavonoids from O.basilicum were determined by Box-Behnken design with response surface methodology.Response surface plots showed that the optional four independent variables significantly influenced the extraction yield of total flavonoids.The extraction parameters for the highest total flavonoids yield were optimized as:extraction temperature of 79.74℃,ethanol concentration of 77.63%,ratio of liquid to material of 29.72:1(mL/g),and extraction time of 2.06 h.The average yield of total flavonoids under above optimum parameters was 42.61 mg of rutin equivalents per g of extract dry matter,which was in good agreement with the predicted value of 40.23 mg/g.These optimized conditions could be useful for the extraction of flavonoids from O.basilicum.
