Magnesium-based materials,including magnesium alloys,have emerged as a promising class of biodegradable materials with potential applications in cancer therapy due to their unique properties,including biocompatibility...Magnesium-based materials,including magnesium alloys,have emerged as a promising class of biodegradable materials with potential applications in cancer therapy due to their unique properties,including biocompatibility,biodegradability,and the ability to modulate the tumor microenvironment.The main degradation products of magnesium alloys are magnesium ions(Mg^(2+)),hydrogen(H_(2)),and magnesium hydroxide(Mg(OH)_(2)).Magnesium ions can regulate tumor growth and metastasis by mediating the inflammatory response and oxidative stress,maintaining genomic stability,and affecting the tumor microenvironment.Similarly,hydrogen can inhibit tumorigenesis through antioxidant and anti-inflammatory properties.Moreover,Mg(OH)_(2) can alter the pH of the microenvironment,impacting tumorigenesis.Biodegradable magnesium alloys serve various functions in clinical applications,including,but not limited to,bonefixation,coronary stents,and drug carriers.Nonetheless,the anti-tumor mechanism associated with magnesium-based materials has not been thoroughly investigated.This review provides a comprehensive overview of the current state of magnesium-based therapies for cancer.It highlights the mechanisms of action,identifies the challenges that must be addressed,and discusses prospects for oncological applications.展开更多
The quality of wrought magnesium(Mg)alloys is closely linked to the quality of the cast ingots.Conventionally casting(CC)Mg-2Y ingots exhibit relatively coarse grain sizes.When CC ingots undergo rolling processing(CC-...The quality of wrought magnesium(Mg)alloys is closely linked to the quality of the cast ingots.Conventionally casting(CC)Mg-2Y ingots exhibit relatively coarse grain sizes.When CC ingots undergo rolling processing(CC-10-R),the resulting Mg-2Y sheets retain coarse grain sizes(~11.87μm),while precipitating a small number of Mg_(24)Y_(5) nanoparticles(~0.26%),as well as forming a strong C-type texture(~10.91).The implementation of controlled diffusion solidification(CDS)effectively refines the grain size of Mg-2Y ingots and increases the content of Mg_(24)Y_(5) particles.When CDS is combined with rolling(CDS-10-R),the grain size is refined to~5.57μm,the precipitation of Mg_(24)Y_(5) nanoparticles is increased to~1.79%,and the C-type texture was weakened to~7.74.The CDS-10-R shows an increase in strength of~51.8% and an enhancement in plasticity of~32.6% compared to CC-10-R.The enhancement in strength is primarily due to fine-grain strengthening(~42.1% contributions)and precipitating strengthening(~39.6% contributions).The improvement in plasticity is attributed to the weakening of the{0001}basal texture,which facilitates the activation of<c+a>slips.Compared to other wrought Mg-Y alloys,Mg-2Y sheets produced by combining CDS with rolling possess exceptional strength-plasticity combinations.This finding presents a novel route to achieving high strength and plasticity in low-alloyed rare-earth Mg alloys.展开更多
Mg/MgH_(2) has garnered significant attention primarily due to its abundant availability and high gravimetric density.Nevertheless,its practical implementation hindered by its high thermodynamic stability and sluggish...Mg/MgH_(2) has garnered significant attention primarily due to its abundant availability and high gravimetric density.Nevertheless,its practical implementation hindered by its high thermodynamic stability and sluggish kinetics.Fortunately,the introduction of transition metal single atom(TM SA)catalysts has emerged as an effective method to enhance the hydrogen storage properties of Mg/MgH_(2).Among these catalysts,the synergistic effect of nanoconfinement and TM SAs plays a pivotal role in the hydriding/dehydriding kinetics of Mg/MgH_(2).However,the effects of varying TM SAs interacting with N modified confined materials on H_(2) adsorption and desorption and underlying mechanisms remain enigmatic.Leveraging DFT calculations,we investigated the potential of combining TM SA catalysts with N-modified Carbon nanomaterials(CNT)to enhance the hydrogenation/dehydrogenation of Mg/MgH_(2).TM SA N-CNTs-Mg/MgH_(2) heterojunction systems encompassing ten 3d/4d transition metals were designed and constructed.We systematically investigated the impact of TM SA N-CNTs on the hydrogen absorption and desorption properties of Mg/MgH_(2) by examining parameters such as the electronic localization function(ELF),distorted charge density distributions,adsorption energies,dissociation energies,electronegativity,and the D-band center.Notably,the energy barriers for Mg/MgH_(2) hydrogenation and dehydrogenation were significantly reduced by 0.2-0.7 eV and 1.6-2.2 eV,respectively,through the catalytic promotion of TM SA N-CNTs.Herein,a novel“electronic-ropeway”effect was proposed to elucidate the underlying mechanism responsible for enhancing the hydrogen absorption and desorption kinetics in Mg/MgH_(2).Specifically,the contribution degree of TM SA N-CNTs and system electronegativity emerged as effective descriptors for predicting the reduced hydrogenation/dehydrogenation energy barriers.It is anticipated that elucidating the role of TM SA-N-CNTs will pave the way for developing innovative strategies to enhance the hydrogen absorption and desorption kinetics of Mg/MgH_(2) systems,thereby providing valuable design principles for the construction of novel Mg/MgH_(2) hydrogen storage materials.展开更多
The Mg(NH_(2))_(2)-2LiH composite system is a promising vehicle-mounted hydrogen sto rage material,but its application is limited due to serious thermodynamic and kinetic barriers.Adding additives can effectively opti...The Mg(NH_(2))_(2)-2LiH composite system is a promising vehicle-mounted hydrogen sto rage material,but its application is limited due to serious thermodynamic and kinetic barriers.Adding additives can effectively optimize their hydrogen absorption and desorption kinetics and thermodynamic performance.In this work the comprehensive hydrogen storage performance of Mg(NH_(2))_(2)-2LiH with extremely small nano rare earth borides is improved,and a series of characterization methods and density functional theory(DFT)calculation systems was combined to study its hydrogen storage improvement mechanism.The research results show that the method of adding 5 wt%molten salt to prepare nano CeB_(6)(24.5 nm)can significantly reduce the initial hydrogen absorption/release temperature of Mg(NH_(2))_(2)-2LiH from 110/130to 45/90℃,inhibit the generation of ammonia by-products,and improve hydrogen purity.Under lowtemperature hydrogen absorption conditions at 120℃,the improved sample can absorb 2.81 wt%hydrogen gas,with a hydrogen absorption capacity more than 3.5 times of the unmodified sample.The amount of hydrogen released at 150℃reaches 3.35 wt%,which is more than twice that of the pristine sample,demonstrating excellent hydrogen absorption and release kinetics performance.After 10 consecutive hydrogen cycles,4.64 wt%hydrogen can still be released,and the cycle retention rate can be increased from 85%before improvement to nearly 100%,demonstrating good reversibility.Mechanism studies show that nano CeB_(6)can effectively weaken the Mg-N and N-H bonds of Mg(NH_(2))_(2)and inhibit the polycrystalline transformation of the hydrogen evolution product Li_(2)MgN_(2)H_(2)at high temperatures.It can also provide nucleation active sites for hydrogen absorption and desorption in the material,making the system possess superior hydrogen absorption and desorption performance and cycling stability.This study provides new insights into the role of rare earth borides in Mg(NH_(2))_(2)-2LiH hydrogen storage materials,both experimentally and theoretically.展开更多
The preparation of high-strengthα-hemihydrate gypsum(α-HH)from dihydrate gypsum(DH)is a potential way to improve the utilization rate of industrial gypsum.α-HH with a low aspect ratio was prepared by atmospheric sa...The preparation of high-strengthα-hemihydrate gypsum(α-HH)from dihydrate gypsum(DH)is a potential way to improve the utilization rate of industrial gypsum.α-HH with a low aspect ratio was prepared by atmospheric salt solution method,using Mg(NO_(3))_(2)solution as the salt medium.The effects of reaction temperature,reaction time,Mg(NO_(3))_(2)concentration,pH value,and the solid-to-liquid ratio on the purity,yield and aspect ratio of the product were investigated systematically.Under the optimal reaction conditions of 95℃,4 h,40%(mass)Mg(NO_(3))_(2),pH 5,and a solid—liquid ratio of 1:5,the yield and purity of the product could reach 89.67%and 99.85%,respectively.Additionally,the average aspect ratio of this product was 2.02,and the compressive strength reached 58.2 MPa.The regulation mechanism was studied by calculating the adsorption energies of Mg(NO_(3))_(2)on different crystal planes ofα-HH,which indicated that Mg(NO_(3))_(2)exhibited the strongest adsorption on the(111)plane,and this preferential adsorption retarded the axial growth ofα-HH,resulting in a reduced aspect ratio of the crystals.These findings suggest that the Mg(NO_(3))_(2)solution is an effective approach for preparing highstrengthα-HH with controlled morphology.展开更多
Mg alloys have the defects of low stiffness,low strength,and high coefficient of thermal expansion(CTE).The composites strategy and its architecture design are effective approaches to improve the comprehensive perform...Mg alloys have the defects of low stiffness,low strength,and high coefficient of thermal expansion(CTE).The composites strategy and its architecture design are effective approaches to improve the comprehensive performance of materials,but the processing difficulty,especially in ceramics forming,limits the control and innovation of material architecture.Here,combined with 3D printing and squeeze infiltration technology,two precisely controllable architectures of AZ91/Al_(2)O_(3)interpenetrating phase composites(IPC)with ceramic scaffold were prepared.The interface,properties and impact of different architecture on IPC performance were studied by experiments and finite element simulation.The metallurgical bonding of the interface was realized with the formation of MgAl_(2)O_(4)reaction layer.The IPC with 1 mm circular hole scaffold(1C-IPC)exhibited significantly improved elastic modulus of 164 GPa,high compressive strength of 680 MPa,and good CTE of 12.91×10^(-6)K^(−1),which were 3.64 times,1.98 times and 55%of the Mg matrix,respectively.Their elastic modulus,compressive strength,and CTE were superior to the vast majority of Mg alloys and Mg based composites.The reinforcement and matrix were bicontinuous and interpenetrating each other,which played a critical role in ensuring the potent strengthening effect of the Al_(2)O_(3)reinforcement by efficient load transfer.Under the same volume fraction of reinforcements,compared to IPC with 1 mm hexagonal hole scaffold(1H-IPC),the elastic modulus and compressive strength of 1C-IPC increased by 15%and 28%,respectively,which was due to the reduced stress concentration and more uniform stress distribution of 1C-IPC.It shows great potential of architecture design in improving the performance of composites.This study provides architectural design strategy and feasible preparation method for the development of high performance materials.展开更多
Chemical vapor deposition is the predominant method to prepare MgAl_(2)O_(4)fibers.However,it faces several challenges,including exorbitantly high reaction temperatures,substantial production costs,and relatively low ...Chemical vapor deposition is the predominant method to prepare MgAl_(2)O_(4)fibers.However,it faces several challenges,including exorbitantly high reaction temperatures,substantial production costs,and relatively low yields.In this study,porous MgAl_(2)O_(4)fibers were fabricated through a solid-state reaction method,utilizing MgSO_(4)·5Mg(OH)_(2)·3H_(2)O whiskers as templates,mixed with either aluminum sol orα-Al_(2)O_(3)micropowder.The impact of various parameters on the synthesis of porous MgAl_(2)O_(4)fibres was systematically investigated,including the heat treatment temperature(1000,1100 and 1300℃),the holding time(3 and 10 h)and the aluminum source(aluminum sol orα-Al_(2)O_(3)micropowder).The results reveal that:(1)in comparison with fibers synthesized usingα-Al_(2)O_(3)as the aluminum source,those prepared with aluminum sol exhibit a significantly higher generation amount of MgAl_(2)O_(4);(2)as the heat treatment temperature increases,Al_(2)O_(3)gradually reacts with MgO,continuously increasing the formation amount of porous MgAl_(2)O_(4)with small and uniformly distributed nanopores,and the synthesized porous MgAl_(2)O_(4)fibres have small and uniform nanopores;(3)the optimal synthesis process involves using aluminum sol as the aluminum source and firing at 1300℃ for 3 h.展开更多
文摘Magnesium-based materials,including magnesium alloys,have emerged as a promising class of biodegradable materials with potential applications in cancer therapy due to their unique properties,including biocompatibility,biodegradability,and the ability to modulate the tumor microenvironment.The main degradation products of magnesium alloys are magnesium ions(Mg^(2+)),hydrogen(H_(2)),and magnesium hydroxide(Mg(OH)_(2)).Magnesium ions can regulate tumor growth and metastasis by mediating the inflammatory response and oxidative stress,maintaining genomic stability,and affecting the tumor microenvironment.Similarly,hydrogen can inhibit tumorigenesis through antioxidant and anti-inflammatory properties.Moreover,Mg(OH)_(2) can alter the pH of the microenvironment,impacting tumorigenesis.Biodegradable magnesium alloys serve various functions in clinical applications,including,but not limited to,bonefixation,coronary stents,and drug carriers.Nonetheless,the anti-tumor mechanism associated with magnesium-based materials has not been thoroughly investigated.This review provides a comprehensive overview of the current state of magnesium-based therapies for cancer.It highlights the mechanisms of action,identifies the challenges that must be addressed,and discusses prospects for oncological applications.
基金supported by the National Natural Science Foundation of China(No.52474437).
文摘The quality of wrought magnesium(Mg)alloys is closely linked to the quality of the cast ingots.Conventionally casting(CC)Mg-2Y ingots exhibit relatively coarse grain sizes.When CC ingots undergo rolling processing(CC-10-R),the resulting Mg-2Y sheets retain coarse grain sizes(~11.87μm),while precipitating a small number of Mg_(24)Y_(5) nanoparticles(~0.26%),as well as forming a strong C-type texture(~10.91).The implementation of controlled diffusion solidification(CDS)effectively refines the grain size of Mg-2Y ingots and increases the content of Mg_(24)Y_(5) particles.When CDS is combined with rolling(CDS-10-R),the grain size is refined to~5.57μm,the precipitation of Mg_(24)Y_(5) nanoparticles is increased to~1.79%,and the C-type texture was weakened to~7.74.The CDS-10-R shows an increase in strength of~51.8% and an enhancement in plasticity of~32.6% compared to CC-10-R.The enhancement in strength is primarily due to fine-grain strengthening(~42.1% contributions)and precipitating strengthening(~39.6% contributions).The improvement in plasticity is attributed to the weakening of the{0001}basal texture,which facilitates the activation of<c+a>slips.Compared to other wrought Mg-Y alloys,Mg-2Y sheets produced by combining CDS with rolling possess exceptional strength-plasticity combinations.This finding presents a novel route to achieving high strength and plasticity in low-alloyed rare-earth Mg alloys.
基金financed by the National Key Research and Development Program of China [grants number 2023YFB3809101]the National Natural Science Foundation of China [grants number 52471225, 52271212, 52201250]+1 种基金the Natural Science Foundation of Hebei Province [grants number E2018502054]the Fundamental Research Funds for the Central Universities [grants number 2023MS148]
文摘Mg/MgH_(2) has garnered significant attention primarily due to its abundant availability and high gravimetric density.Nevertheless,its practical implementation hindered by its high thermodynamic stability and sluggish kinetics.Fortunately,the introduction of transition metal single atom(TM SA)catalysts has emerged as an effective method to enhance the hydrogen storage properties of Mg/MgH_(2).Among these catalysts,the synergistic effect of nanoconfinement and TM SAs plays a pivotal role in the hydriding/dehydriding kinetics of Mg/MgH_(2).However,the effects of varying TM SAs interacting with N modified confined materials on H_(2) adsorption and desorption and underlying mechanisms remain enigmatic.Leveraging DFT calculations,we investigated the potential of combining TM SA catalysts with N-modified Carbon nanomaterials(CNT)to enhance the hydrogenation/dehydrogenation of Mg/MgH_(2).TM SA N-CNTs-Mg/MgH_(2) heterojunction systems encompassing ten 3d/4d transition metals were designed and constructed.We systematically investigated the impact of TM SA N-CNTs on the hydrogen absorption and desorption properties of Mg/MgH_(2) by examining parameters such as the electronic localization function(ELF),distorted charge density distributions,adsorption energies,dissociation energies,electronegativity,and the D-band center.Notably,the energy barriers for Mg/MgH_(2) hydrogenation and dehydrogenation were significantly reduced by 0.2-0.7 eV and 1.6-2.2 eV,respectively,through the catalytic promotion of TM SA N-CNTs.Herein,a novel“electronic-ropeway”effect was proposed to elucidate the underlying mechanism responsible for enhancing the hydrogen absorption and desorption kinetics in Mg/MgH_(2).Specifically,the contribution degree of TM SA N-CNTs and system electronegativity emerged as effective descriptors for predicting the reduced hydrogenation/dehydrogenation energy barriers.It is anticipated that elucidating the role of TM SA-N-CNTs will pave the way for developing innovative strategies to enhance the hydrogen absorption and desorption kinetics of Mg/MgH_(2) systems,thereby providing valuable design principles for the construction of novel Mg/MgH_(2) hydrogen storage materials.
基金Project supported by the National Natural Science Foundation of China(51971199,51771171)。
文摘The Mg(NH_(2))_(2)-2LiH composite system is a promising vehicle-mounted hydrogen sto rage material,but its application is limited due to serious thermodynamic and kinetic barriers.Adding additives can effectively optimize their hydrogen absorption and desorption kinetics and thermodynamic performance.In this work the comprehensive hydrogen storage performance of Mg(NH_(2))_(2)-2LiH with extremely small nano rare earth borides is improved,and a series of characterization methods and density functional theory(DFT)calculation systems was combined to study its hydrogen storage improvement mechanism.The research results show that the method of adding 5 wt%molten salt to prepare nano CeB_(6)(24.5 nm)can significantly reduce the initial hydrogen absorption/release temperature of Mg(NH_(2))_(2)-2LiH from 110/130to 45/90℃,inhibit the generation of ammonia by-products,and improve hydrogen purity.Under lowtemperature hydrogen absorption conditions at 120℃,the improved sample can absorb 2.81 wt%hydrogen gas,with a hydrogen absorption capacity more than 3.5 times of the unmodified sample.The amount of hydrogen released at 150℃reaches 3.35 wt%,which is more than twice that of the pristine sample,demonstrating excellent hydrogen absorption and release kinetics performance.After 10 consecutive hydrogen cycles,4.64 wt%hydrogen can still be released,and the cycle retention rate can be increased from 85%before improvement to nearly 100%,demonstrating good reversibility.Mechanism studies show that nano CeB_(6)can effectively weaken the Mg-N and N-H bonds of Mg(NH_(2))_(2)and inhibit the polycrystalline transformation of the hydrogen evolution product Li_(2)MgN_(2)H_(2)at high temperatures.It can also provide nucleation active sites for hydrogen absorption and desorption in the material,making the system possess superior hydrogen absorption and desorption performance and cycling stability.This study provides new insights into the role of rare earth borides in Mg(NH_(2))_(2)-2LiH hydrogen storage materials,both experimentally and theoretically.
基金financial supported by the Opening Project of Hubei Yihua-Sichuan University Joint Innovation Research Center for new chemical materials(24H1402)Fundamental Research Funds for the Central Universities(SCU2024D009)the National Key Research and Development Program of China(2019YFC1905800)。
文摘The preparation of high-strengthα-hemihydrate gypsum(α-HH)from dihydrate gypsum(DH)is a potential way to improve the utilization rate of industrial gypsum.α-HH with a low aspect ratio was prepared by atmospheric salt solution method,using Mg(NO_(3))_(2)solution as the salt medium.The effects of reaction temperature,reaction time,Mg(NO_(3))_(2)concentration,pH value,and the solid-to-liquid ratio on the purity,yield and aspect ratio of the product were investigated systematically.Under the optimal reaction conditions of 95℃,4 h,40%(mass)Mg(NO_(3))_(2),pH 5,and a solid—liquid ratio of 1:5,the yield and purity of the product could reach 89.67%and 99.85%,respectively.Additionally,the average aspect ratio of this product was 2.02,and the compressive strength reached 58.2 MPa.The regulation mechanism was studied by calculating the adsorption energies of Mg(NO_(3))_(2)on different crystal planes ofα-HH,which indicated that Mg(NO_(3))_(2)exhibited the strongest adsorption on the(111)plane,and this preferential adsorption retarded the axial growth ofα-HH,resulting in a reduced aspect ratio of the crystals.These findings suggest that the Mg(NO_(3))_(2)solution is an effective approach for preparing highstrengthα-HH with controlled morphology.
基金supported by the National Key Research and Development Program of China(No.2022YFB3708400)the National Natural Science Foundation of China(No.52305158)+1 种基金the Young Elite Scientists Sponsorship Program by CAST(No.2022QNRC001)the Science Innovation Foundation of Shanghai Academy of Spaceflight Technology(No.USCAST2021-18).
文摘Mg alloys have the defects of low stiffness,low strength,and high coefficient of thermal expansion(CTE).The composites strategy and its architecture design are effective approaches to improve the comprehensive performance of materials,but the processing difficulty,especially in ceramics forming,limits the control and innovation of material architecture.Here,combined with 3D printing and squeeze infiltration technology,two precisely controllable architectures of AZ91/Al_(2)O_(3)interpenetrating phase composites(IPC)with ceramic scaffold were prepared.The interface,properties and impact of different architecture on IPC performance were studied by experiments and finite element simulation.The metallurgical bonding of the interface was realized with the formation of MgAl_(2)O_(4)reaction layer.The IPC with 1 mm circular hole scaffold(1C-IPC)exhibited significantly improved elastic modulus of 164 GPa,high compressive strength of 680 MPa,and good CTE of 12.91×10^(-6)K^(−1),which were 3.64 times,1.98 times and 55%of the Mg matrix,respectively.Their elastic modulus,compressive strength,and CTE were superior to the vast majority of Mg alloys and Mg based composites.The reinforcement and matrix were bicontinuous and interpenetrating each other,which played a critical role in ensuring the potent strengthening effect of the Al_(2)O_(3)reinforcement by efficient load transfer.Under the same volume fraction of reinforcements,compared to IPC with 1 mm hexagonal hole scaffold(1H-IPC),the elastic modulus and compressive strength of 1C-IPC increased by 15%and 28%,respectively,which was due to the reduced stress concentration and more uniform stress distribution of 1C-IPC.It shows great potential of architecture design in improving the performance of composites.This study provides architectural design strategy and feasible preparation method for the development of high performance materials.
文摘Chemical vapor deposition is the predominant method to prepare MgAl_(2)O_(4)fibers.However,it faces several challenges,including exorbitantly high reaction temperatures,substantial production costs,and relatively low yields.In this study,porous MgAl_(2)O_(4)fibers were fabricated through a solid-state reaction method,utilizing MgSO_(4)·5Mg(OH)_(2)·3H_(2)O whiskers as templates,mixed with either aluminum sol orα-Al_(2)O_(3)micropowder.The impact of various parameters on the synthesis of porous MgAl_(2)O_(4)fibres was systematically investigated,including the heat treatment temperature(1000,1100 and 1300℃),the holding time(3 and 10 h)and the aluminum source(aluminum sol orα-Al_(2)O_(3)micropowder).The results reveal that:(1)in comparison with fibers synthesized usingα-Al_(2)O_(3)as the aluminum source,those prepared with aluminum sol exhibit a significantly higher generation amount of MgAl_(2)O_(4);(2)as the heat treatment temperature increases,Al_(2)O_(3)gradually reacts with MgO,continuously increasing the formation amount of porous MgAl_(2)O_(4)with small and uniformly distributed nanopores,and the synthesized porous MgAl_(2)O_(4)fibres have small and uniform nanopores;(3)the optimal synthesis process involves using aluminum sol as the aluminum source and firing at 1300℃ for 3 h.
