Rechargeable magnesium batteries(RMBs)possess the merits of greater theoretical capacity,cheaper magnesium metal and not easily producing branched crystals,and greater safety.Therefore,the current researches mainly co...Rechargeable magnesium batteries(RMBs)possess the merits of greater theoretical capacity,cheaper magnesium metal and not easily producing branched crystals,and greater safety.Therefore,the current researches mainly concentrate on the exploration of high-performance RMBs in the initial stage,but still face many gigantic challenges.Herein,petal-shaped nanorods CoS/CuS materials are successfully synthesized as RMBs cathode materials through a two-step metal sulfide template-free solvent-thermal synthesis method,which can effectively improve the reaction kinetics due to the petal-like nano-structure and provide rich electrochemically active sites to decrease the transport barrier of Mg^(2+),thus contributing to the enhancement of the reaction kinetics of magnesium storage in RMBs.The electrochemical performance test illustrates that CoS/CuS composite nanomaterials can considerably improve the charging and discharging specific capacity of the batteries as well as the voltage of the batteries due to the existing synergistic effect between them.The specific capacity of CoS/CuS cathode still can still be maintained as high as 62.8 mAh g^(−1)after 300 cycles at 200 mA g^(−1).And the specific capacity of this electrode material changes from 180.6 mAh g^(−1)to 30 mAh g^(−1)at the current densities from 100 mA g^(−1)to 1000 mA g^(−1),and when the current density is restored to 100 mA g^(−1),the specific capacity gradually recovered to 178.6 mAh g^(−1),which showed better rate performance and ultra-high cycling stability.This work highlights how the introduction of CuS into CoS nanostructures can benefit the reversibility and cyclicity of the magnesium storage reaction and offers an original and practical route for the modification of RMBs electrode materials with good electrochemical properties.展开更多
Bone defects have serious economic and clinical impacts;however,despite improvements in bone defect management,the range of clinical outcomes remains limited.A variety of biomaterials have been used to treat complex b...Bone defects have serious economic and clinical impacts;however,despite improvements in bone defect management,the range of clinical outcomes remains limited.A variety of biomaterials have been used to treat complex bone defects.However,final bone repair outcomes may be adversely affected by poor osteogenic capacity and risk of infection.Consequently,therapeutic methods are required that reduce bacterial contamination and increase the use of osteogenic biomaterials.Herein,we report the preparation of poly(lactic acid-coglycolic acid)(PLGA)microspheres coloaded with magnesium(Mg^(2+))and gallium(Ga^(3+))ions(Mg-Ga@PLGA),which can fill irregular bone defects and show good biosafety.During in vitro testing,Mg-Ga@PLGA not only showed a synergistic effect on promoting osteogenic differentiation but also inhibited osteoclastic differentiation.Moreover,we found that Mg-Ga@PLGA demonstrated an antibacterial effect.During in vivo testing,Mg Ga@PLGA exhibited strong in situ osteogenic ability.In conclusion,Mg-Ga@PLGA has good potential for treating bone defects at risk of infection.展开更多
Carbon-based materials have gained significant attention in anticancer treatment because of their exceptional biocompatibility,yet critical challenges persist in establishing definitive correlations between their poro...Carbon-based materials have gained significant attention in anticancer treatment because of their exceptional biocompatibility,yet critical challenges persist in establishing definitive correlations between their porous structures and functional performance.We report the use of a silica template to guide pore formation in the design of mesoporous carbon spheres(mC)with tailored pore structures for improved combined photothermal-chemotherapy.The mesopore size of mC has been adjusted by kinetic control of the resin polymerization and silica hydrolysis.Structural characterization showed that 4.4 nm mesopores enabled an exceptional gemcitabine loading of 228 mg g^(−1) and a sustained pH/thermal dual-responsive release with>70%drug release under near-infrared(NIR)irradiation.Finite element analysis demonstrated pore size-dependent heat transfer dynamics,with the improved mC achieving a superior photothermal conversion efficiency of 62%by a combination of N-doping and defect engineering.In vitro evaluations confirmed outstanding biocompatibility with>95%cell viability at 200μg mL^(−1) and potent tumor suppression in pancreatic and biliary cancer models with an~5%cell viability at 25μg mL^(−1) where combined therapy showed a 3.7-fold increased cytotoxicity over monotherapy.The improved structure of mC facilitated cascade therapeutic effects with enhanced tumor permeability derived from NIR-triggered hyperthermia and prolonged therapeutic exposure due to pH-responsive drug release.This pore engineering strategy establishes a structure-function process for next-generation theranostic platforms,addressing the critical limitations of conventional pancreatic and biliary cancer therapies through spatiotemporal control of multimodal treatment.展开更多
This comprehensive study investigates the formation and evolution of intermetallic compounds during the solidification process of magnesium alloys using advanced micro X-ray computed tomography.By analyzing both commo...This comprehensive study investigates the formation and evolution of intermetallic compounds during the solidification process of magnesium alloys using advanced micro X-ray computed tomography.By analyzing both common industrial Mg-Al-Zn alloys and a novel rare earth-containing Mg-Ni-Gd-Y alloy,we aim to characterize the nucleation,growth,and distribution of Al-Mn and eutectic intermetallics across various stages of solidification.The non destructive imaging technique employed in this research provides high-resolution,three-dimensional insights into the microstructural development,allowing for a detailed examination of the morphology,spatial arrangement,and interconnectivity of intermetallic phases.This approach overcomes limitations of traditional two-dimensional metallographic methods,offering a more comprehensive understanding of the complex three-dimensional structures formed during solidification.展开更多
Lithium-sulfur(Li-S)batteries boast a theoretical energy density as high as 2600 Wh·kg^(−1),positioning them as a highly attractive option for future advanced energy storage systems.Challenges such as slow transf...Lithium-sulfur(Li-S)batteries boast a theoretical energy density as high as 2600 Wh·kg^(−1),positioning them as a highly attractive option for future advanced energy storage systems.Challenges such as slow transformation kinetics and shuttle effects associated with lithium polysulfides(LiPSs)have seriously hindered their practical applications.In this paper,we present a new method for the synthesis of hollow carbon-sphere-supported Co monatomic catalysts(Co-N-C).This new synthesis method achieves pyrolytic coordination using a precursor rich in imide(-RC=N-)polymers.This synthesis method not only improves the adsorbability and catalytic activity of LiPS but also significantly weakens the shuttle effect and generates Co-N-C with superior conductivity,abundant hollow structures,and a high specific surface area,thus efficiently capturing and restricting the movement of LiPS intermediates.The dispersed Co monoatomic catalysts(Co SACs)were anchored to a highly conductive nitrogen-doped carbon framework and exhibited symmetric N-coordination active sites(Co-N_(4))to ensure fast redox kinetics of LiPS and Li_(2)S_(2)/Li_(2)S solid-state products.The lithium-sulfur battery with Co-N-C as the sulfur carrier showed excellent discharging capacity of 1146.6 mAh·g^(−1) at a discharge rate of 0.5 C and maintained excellent performance at a high discharge rate of 2 C.The capacity decay rate in 500 cycles was only 0.086%per cycle,reflecting excellent long-term cycle stability.This study highlights the key role of the synergistic effect between single-atom cobalt catalysts and hollow carbon spheres in enhancing the efficiency of lithium-sulfur(Li-S)batteries.It also provides valuable insights into the construction and fabrication of highly active monatomic catalysts.The catalytic conversion efficiency of lithium polysulfides is significantly enhanced when embedded in hollow carbon architectures,which serves as a critical strategy for optimizing the electrochemical behavior of next-generation Li-S batteries.展开更多
Magnesium hydride(MgH_(2)) demonstrates immense potential as a solid-state hydrogen storage material,while its commercial utilization is impeded by the elevated operating temperature and sluggish reaction kinetics.Her...Magnesium hydride(MgH_(2)) demonstrates immense potential as a solid-state hydrogen storage material,while its commercial utilization is impeded by the elevated operating temperature and sluggish reaction kinetics.Herein,a MOF derived multi-phase FeNi_(3)-S catalyst was specially designed for efficient hydrogen storage in MgH_(2).Experiments confirmed that the incorporation of FeNi_(3)-S into MgH_(2) significantly lowered the desorption temperature and accelerated the kinetics of hydrogen desorption and reabsorption.The initial dehydrogenation temperature of the MgH_(2)+10 wt% FeNi_(3)-S composite was 202 ℃,which was 123 ℃ lower than that of pure MgH_(2).At 325 ℃,the MgH_(2)+10 wt% FeNi_(3)-S composite released 6.57 wt% H_(2)(fully dehydrogenated) within 1000 s.Remarkably,MgH_(2)+ 10 wt% FeNi_(3)-S composite initiated rehydrogenation at room temperature and rapidly absorbed 2.49 wt% H_(2) within 30 min at 100 ℃.Moreover,6.3 wt% H_(2) was still retained after 20 cycles at 300 ℃,demonstrating the superior cycling performance of the MgH_(2)+10 wt% FeNi_(3)-S composite.The activation energy fitting calculations further evidenced the addition of FeNi_(3)-S enhanced the de/resorption kinetics of MgH_(2)(E_(a)= 98.6 k J/mol and 43.3 k J/mol,respectively).Through phase and microstructural analysis,it was determined that the exceptional hydrogen storage performance of the composite was attributed to the in-situ formation of Mg/Mg_(2)Ni + Fe/MgS and MgH_(2)/Mg_(2)NiH_(4)+Fe/MgS hydrogen storage systems.Further mechanistic analysis revealed that Mg_(2)Ni/Mg_(2)NiH_(4) served as “hydrogen pump” and Fe/Mg S served as “hydrogen diffusion channel”,thus accelerating the dissociation and recombination of hydrogen molecules.In conclusion,this work offers insight into catalysts combining transition metal alloys and transition metal sulfide for exerting muti-phase synergistic effect on boosting the dehydrogenation/hydrogenation reactions of MgH_(2),which can also inspire future pioneering work on designing and fabricating high efficient catalysts in other energy storage related areas.展开更多
Magnesium-based anode materials have attracted significant attention in the energy storage domain because of their high theoretical capacities and low electrochemical potentials.However,in conventional electrolyte sys...Magnesium-based anode materials have attracted significant attention in the energy storage domain because of their high theoretical capacities and low electrochemical potentials.However,in conventional electrolyte systems,magnesium metal electrodes dynamically generate an ion-blocking surface layer,resulting in prominent voltage polarization,which severely limits their practical applications.In this study,ZIF-8/carbon nanotubes(CNTs)coatings were used to modify the anodes of magnesium batteries.Compared with the unaltered magnesium battery,the voltage lag time of the ZIF-8/CNTs coating was shortened from 4 s before modification to 0.26 s,and the battery impedance was lowered by two orders of magnitude.The duration of the discharge platform was increased from 4 h before modification to 6-10 h,the anode utilization rate was more than doubled,and the specific energy density was significantly enhanced compared with the battery before modification.The mechanism indicates that the ZIF-8/CNTs coating can limit the infiltration of corrosive substances,extend their transmission path,and offer more effective protection to the magnesium anode.The incorporation of CNTs improves the conductivity of the battery,and it significantly improves the electrochemical performance of the magnesium battery.展开更多
Despite the superior advantages of specific emitter identification in extracting emitter features from in-phase and quadrature(I/Q)signals,challenges persist due to signal-type confusion and background noise interfere...Despite the superior advantages of specific emitter identification in extracting emitter features from in-phase and quadrature(I/Q)signals,challenges persist due to signal-type confusion and background noise interference.To address those limitations,this paper proposes a multi-channel contrast prediction coding and complex-valued residuals network(MCPC-MCVResNet)framework.This model employs contrast prediction techniques to directly extract discriminative features from electromagnetic signal sequences,effectively capturing both amplitude and phase information within I/Q data.A core innovation of this approach is the sphere space softmax(SS-softmax)loss,which optimizes intra-class clustering density of while establishing well-defined boundaries between distinct emitters.The SS-softmax mechanism significantly enhances the model's capacity to discern subtle variations among radiation emitters.Experimental results demonstrate superior identification accuracy,rapid convergence,and exceptional robustness in low signal-to-noise ratio environments.展开更多
Micro-sized anatase TiO_(2) displays inferior capacity as cathode material for magnesium ion batteries because of the higher diffusion energy barrier of Mg^(2+)in anatase TiO_(2) lattice.Herein,we report that nanosize...Micro-sized anatase TiO_(2) displays inferior capacity as cathode material for magnesium ion batteries because of the higher diffusion energy barrier of Mg^(2+)in anatase TiO_(2) lattice.Herein,we report that nanosized anatase TiO_(2) exposed(001)facet doubles the capacity compared to the micro-sized sample ascribed to the interfacial Mg^(2+)ion storage.First-principles calculations reveal that the diffusion energy barrier of Mg^(2+)on the(001)facet is significantly lower than those in the bulk phase and on(100)facet,and the adsorption energy of Mg^(2+)on the(001)facet is also considerably lower than that on(100)facet,which guarantees superior interfacial Mg^(2+)storage of(001)facet.Moreover,anatase TiO_(2) exposed(001)facet displays a significantly higher capacity of 312.9 mAh g^(−1) in Mg-Li dual-salt electrolyte compared to 234.3 mAh g^(−1) in Li salt electrolyte.The adsorption energies of Mg^(2+)on(001)facet are much lower than the adsorption energies of Li+on(001)facet,implying that the Mg^(2+)ion interfacial storage is more favorable.These results highlight that controlling the crystal facet of the nanocrystals effectively enhances the interfacial storage of multivalent ions.This work offers valuable guidance for the rational design of high-capacity storage systems.展开更多
The oxidation behaviour of molten ZK60 and ME20 magnesium alloys in 1% 1,1,1,2-tetrafluoroethane/air atmospheres at 720 °C was compared with that of molten magnesium. The oxidation kinetics of these three melts w...The oxidation behaviour of molten ZK60 and ME20 magnesium alloys in 1% 1,1,1,2-tetrafluoroethane/air atmospheres at 720 °C was compared with that of molten magnesium. The oxidation kinetics of these three melts was determined by thermograyimetric measuring instrument, and the surface films of the oxidized samples were examined by scanning electron microscope (SEM), X-ray diffractometry (XRD) and X-ray photoelectron spectroscopy (XPS). The results show that the oxidation rate of molten ZK60 or ME20 alloys is much lower than that of molten magnesium in 1% 1,1,1,2-tetrafluoroethane/air atmospheres. The surface film formed on the molten magnesium is composed of MgF2, MgO and C, while the film formed on ZK60 melt mainly consists of MgF2, MgO, C and some ZrF4, and the film on ME20 mainly consists of MgF2, MgO, C and a small amount of CeF4. The good oxidation resistances of ZK60 and ME20 alloy melts may be caused by their major alloying elements Zr and Ce, respectively.展开更多
Rechargeable magnesium batteries(RMBs),as one of the most promising candidates for efficient energy storage devices with high energy,power density and high safety,have attracted increasing attention.However,searching ...Rechargeable magnesium batteries(RMBs),as one of the most promising candidates for efficient energy storage devices with high energy,power density and high safety,have attracted increasing attention.However,searching for suitable cathode materials with fast diffusion kinetics and exploring their magnesium storage mechanisms remains a great challenge.Cu S submicron spheres,made by a facile low-temperature synthesis strategy,were applied as the high-performance cathode for RMBs in this work,which can deliver a high specific capacity of 396mAh g^(-1)at 20 mA g^(-1) and a remarkable rate capacity of 250 m Ah g^(-1)at 1000 mA g^(-1).The excellent rate performance can be assigned to the nano needle-like particles on the surface of Cu S submicron spheres,which can facilitate the diffusion kinetics of Mg^(2+).Further storage mechanism investigations illustrate that the Cu S cathodes experience a two-step conversion reaction controlled by diffusion during the electrochemical reaction process.This work could make a contribution to the study of the enhancement of diffusion kinetics of Mg2+and the reaction mechanism of RMBs.展开更多
Surface films that formed on molten AZ91D magnesium alloy in S02/air cover gases at 680 ℃ in a sealed furnace were characterized by scanning electron microscopy, energy dispersive spectroscopy, X-ray diffraction and ...Surface films that formed on molten AZ91D magnesium alloy in S02/air cover gases at 680 ℃ in a sealed furnace were characterized by scanning electron microscopy, energy dispersive spectroscopy, X-ray diffraction and Auger electron spectroscopy. It is revealed that the film formed on molten AZ91D alloy surface in cover gas with high air content can prevent the molten AZ91D alloy from oxidation and ignition. The surface film contained three elements, namely magnesium, oxygen and sulfur, and was mainly composed of MgO and MgS. The properties of the film depended on air content in the cover gas and holding time. Thermodynamic calculation showed that MgSO4 was the stable phase, and it was concluded that the formation of MgS04 was important for the formation of the protective surface film in S02/air atmospheres.展开更多
Efficient lubrication of magnesium alloys is a highly challenging topic in the field of tribology.In this study,magnesium silicate hydroxide(MSH)nanotubes with serpentine structures were synthesized.The tribological b...Efficient lubrication of magnesium alloys is a highly challenging topic in the field of tribology.In this study,magnesium silicate hydroxide(MSH)nanotubes with serpentine structures were synthesized.The tribological behavior of AZ91D magnesium alloy rubbed against GCr15 steel was studied under lubricating oil with surface-modified MSH nanotubes as additives.The effects of the concentration,applied load,and reciprocating frequency on the friction and wear of the AZ91D alloy were studied using an SRV-4 sliding wear tester.Results show a decrease of 18.7–68.5%in friction coefficient,and a reduction of 19.4–54.3%in wear volume of magnesium alloy can be achieved by applying the synthetic serpentine additive under different conditions.A suspension containing 0.3 wt.%MSH was most efficient in reducing wear and friction.High frequency and medium load were more conducive to improving the tribological properties of magnesium alloys.A series of beneficial physical and chemical processes occurring at the AZ91D alloy/steel interface can be used to explain friction and wear reduction based on the characterization of the morphology,chemical composition,chemical state,microstructure,and nanomechanical properties of the worn surface.The synthetic MSH,with serpentine structure and nanotube morphology,possesses excellent adsorbability,high chemical activity,and good self-lubrication and catalytic activity.Therefore,physical polishing,tribochemical reactions,and physicalchemical depositions can occur easily on the sliding contacts.A dense tribolayer with a complex composition and composite structure was formed on the worn surface.Its high hardness,good toughness and plasticity,and prominent lubricity resulted in the improvement of friction and wear,making the synthetic MSH a promising efficient oil additive for magnesium alloys under boundary and mixed lubrication.展开更多
Biliary system,which is responsible for transporting bile from the liver into the intestine,is commonly damaged by inflammation or tumors eventually causing liver failure or death.The implantation of biliary stents ca...Biliary system,which is responsible for transporting bile from the liver into the intestine,is commonly damaged by inflammation or tumors eventually causing liver failure or death.The implantation of biliary stents can effectively alleviate both benign and malignant biliary strictures,but the plastic and metal stents that are currently used cannot degrade and nearly has no beneficial biological effects,therefore their long-term service can result into inflammation,the formation of sludges and re-obstruction of bile duct.In recent years,magnesium(Mg)metal has been received increasing attention in the field of biomedical application due to its excellent biocompatibility,adequate mechanical properties,biodegradability and other advantages,such as anti-inflammatory and anti-tumor properties.The research on biliary stents made of magnesium metals(BSMM)has also made significant progress and a series of experiments in vitro and vivo has proved their possibility.However,there are still some problems holding back BSMM’s clinical use,including rapid corrosion rate and potential harmful reaction.In this review,we would summarize the current research of BSMM,evaluate their clinical benefits,find the choke points,and discuss the solving method.展开更多
Magnesium phosphate cements(MPC)have shown promising applications in many fields,but high raw material prices hinder their development.The production of salt lake MPC(SLMPC)from magnesium slag(MS),a byproduct of lithi...Magnesium phosphate cements(MPC)have shown promising applications in many fields,but high raw material prices hinder their development.The production of salt lake MPC(SLMPC)from magnesium slag(MS),a byproduct of lithium extraction from salt lakes,offers significant environmental and economic advantages.In this study,a low-cost magnesia raw material was obtained through the calcination of MS,which was subsequently utilized in conjunction with KH_(2)PO_(4) to prepare SLMPC.The changes in hydration products,microscopic morphology,solution pH value,and TG content during the SLMPC curing process,and the hydration kinetics equation and model were used to study the hydration processes of SLMPC.The results show that the outcome indicates that the SLMPC system entered the accelerated reaction stage within 6 min after mixing,where the highest heat release rate was 6.29 J·g^(-1)·min^(-1),the maximum heat release was 205.3 J·g^(-1),and the main hydration product appeared at 50-60 min.The hydration behavior of SLMPC exhibits similarities to that of traditional MPC.Specifically,the acceleration phase is governed by an autocatalytic reaction,the deceleration phase is influenced by both autocatalytic reactions and diffusion processes,and the stabilization phase is predominantly controlled by diffusion mechanisms.This paper aims to establish the theoretical foundation for the industrial application of MS and the cost-effective production of MPC.展开更多
In the extraction of potassium from salt lakes,Mg is abundant in the form of bischofite(MgCl_(2)·6H_(2)O),which is not utilized effectively,resulting in the waste of resources and environmental pressure.Anhydrous...In the extraction of potassium from salt lakes,Mg is abundant in the form of bischofite(MgCl_(2)·6H_(2)O),which is not utilized effectively,resulting in the waste of resources and environmental pressure.Anhydrous MgCl_(2) prepared by the dehydration of bischofite is a high-quality raw material for the production of Mg.However,direct calcination of MgCl_(2)·6H_(2)O in industrial dehydration processes leads to a large amount of hydrolysis.The by-products are harmful to the electrolysis process of Mg,causing problems such as sludge formation,low current efficiency,and corrosion in the electrodes.To obtain high-purity anhydrous MgCl_(2),different advanced dehydration processes have been proposed.In this review,we focus on the recent progress of the dehydration process.Firstly,we discuss the molecular structure of MgCl_(2)·6H_(2)O and explain the reason why much hydrolysis occurs in dehydration.Secondly,we introduce the specific dehydration processes,mainly divided into direct dehydration processes and indirect dehydration processes.The direct dehydration processes are classified into gas protection heating and molecular sieve dehydration process.Indirect dehydration processes are classified into thermal dehydration of ammonium carnallite(NH_(4)Cl·MgCl_(2)·6H_(2)O),thermal dehydration of potassium carnallite(KCl·MgCl_(2)·6H_(2)O),thermal decomposition of the[HAE]Cl·MgCl_(2)·6H_(2)O,organic solvent distillation,ionic liquid dehydration process and ammonia complexation process.In the meanwhile,purity of anhydrous MgCl_(2) of each dehydration process,as well as the advantages and disadvantages,is discussed.The characteristics of different processes with a simple economic budget are also given in this paper.Finally,the main challenges are evaluated with suggested directions in the future,aiming to guide the synthesis of high-purity anhydrous MgCl_(2).展开更多
A comprehensive analysis of the microstructure and defects of a thixomolded AZ91D alloy was conducted to elucidate their influences on mechanical properties.Samples were made at injection temperatures ranging from 580...A comprehensive analysis of the microstructure and defects of a thixomolded AZ91D alloy was conducted to elucidate their influences on mechanical properties.Samples were made at injection temperatures ranging from 580 to 640℃.X-ray computed tomography was used to visualize pores,and crystal plasticity finite element simulation was adopted for deformation analysis.The microstructure characterizations reveal a hierarchical cell feature composed of α-Mg and eutectic phases.With the increase of injection temperature,large cell content in the material decreases,while the strength of the alloy increases.The underlying mechanism about strength change is that coarse-grained solids experience smaller stress even in hard orientations.The sample fabricated at a moderate temperature of 620℃ exhibits the highest elongation,least quantity and lower local concentration of pores.The detachment and tearing cracks formed at lower injection temperature and defect bands formed at higher injection temperature add additional crack sources and deteriorate the ductility of the materials.展开更多
As one of the lightest engineering materials,magnesium(Mg)alloy possesses excellent mechanical performance,meeting the needs of versatile engineering fields and holding the potential to address cutting-edge issues in ...As one of the lightest engineering materials,magnesium(Mg)alloy possesses excellent mechanical performance,meeting the needs of versatile engineering fields and holding the potential to address cutting-edge issues in aerospace,electronics,biomedicine.The design of superhydrophobic(SHB)surfaces with micro and nanostructures can endow Mg alloys with multiple functionalities,such as self-cleaning,self-healing,antibacterial,and corrosion resistance.Over the past decade,researchers have drawn inspiration from nature to implement biomimetic design principles,resulting in the rapid development of micro/nanostructured SHB surfaces on Mg alloys,which hold great promise for biomedical applications.This review comprehensively introduces the biomimetic design principles of micro/nanostructured SHB surfaces on Mg alloys,discusses the challenges along with advantages and disadvantages of current preparation methods,and explores the future perspectives for preparing these SHB surfaces,providing strategies to enhance their performance in biomedical applications.展开更多
Precipitation is often used for the preparation of La(OH)_(3)with precipitants of liquid alkali and ammonia.To solve the problems of high cost and wastewater pollution caused by common precipitants,the active MgO synt...Precipitation is often used for the preparation of La(OH)_(3)with precipitants of liquid alkali and ammonia.To solve the problems of high cost and wastewater pollution caused by common precipitants,the active MgO synthesized by pyrolysis was used as the precipitant to prepare La(OH)_(3).The species distribution of LaCl_(3)and LaCl_(3)-MgCl_(2)mixed system solution was calculated,and the kinetic analysis of the precipi-tation process was carried out to confirm the key factors influencing the precipitation of La(OH)_(3).The results show that La(OH)_(3)with D_(50)of 5.57μm,a specific surface area of 25.70 m^(2)/g,a rod-like shape,and MgO content of 0.044 wt%,was successfully prepared by adding active MgO.The precipitation ratio of La reaches 99.92%.The La(OH)_(3)precipitation is controlled by the diffusion process.The activity of MgO has a significant influence on MgO content in the precipitate.The preparation of La(OH)_(3)by active MgO provides a potential way for an eco-friendly preparation method of rare earth.展开更多
Magnesium(Mg)-based bioresorbable stents represent a potentially groundbreaking advancement in cardiovascular therapy;offering tem-porary vessel support and complete biodegradability—addressing limitations of traditi...Magnesium(Mg)-based bioresorbable stents represent a potentially groundbreaking advancement in cardiovascular therapy;offering tem-porary vessel support and complete biodegradability—addressing limitations of traditional stents like in-stent restenosis and long-term com-plications.However,challenges such as rapid corrosion and suboptimal endothelialisation have hindered their clinical adoption.This review highlights the latest breakthroughs in surface modification,alloying,and coating strategies to enhance the mechanical integrity,corrosion resistance,and biocompatibility of Mg-based stents.Key surface engineering techniques,including polymer and bioactive coatings,are ex-amined for their role in promoting endothelial healing and minimising inflammatory responses.Future directions are proposed,focusing on personalised stent designs to optimize efficacy and long-term outcomes,positioning Mg-based stents as a transformative solution in interventional cardiology.展开更多
基金financially supported by the National Natural Science Foundation of China(Nos.21804008,52102209)the International Technological Collaboration Project of Shanghai(No.17520710300)+1 种基金Anhui Provincial Natural Science Foundation(No.2108085QE197)Guangdong Basic and Applied Basic Research Foundation(Nos.2022A1515010834,2020A1515110221).
文摘Rechargeable magnesium batteries(RMBs)possess the merits of greater theoretical capacity,cheaper magnesium metal and not easily producing branched crystals,and greater safety.Therefore,the current researches mainly concentrate on the exploration of high-performance RMBs in the initial stage,but still face many gigantic challenges.Herein,petal-shaped nanorods CoS/CuS materials are successfully synthesized as RMBs cathode materials through a two-step metal sulfide template-free solvent-thermal synthesis method,which can effectively improve the reaction kinetics due to the petal-like nano-structure and provide rich electrochemically active sites to decrease the transport barrier of Mg^(2+),thus contributing to the enhancement of the reaction kinetics of magnesium storage in RMBs.The electrochemical performance test illustrates that CoS/CuS composite nanomaterials can considerably improve the charging and discharging specific capacity of the batteries as well as the voltage of the batteries due to the existing synergistic effect between them.The specific capacity of CoS/CuS cathode still can still be maintained as high as 62.8 mAh g^(−1)after 300 cycles at 200 mA g^(−1).And the specific capacity of this electrode material changes from 180.6 mAh g^(−1)to 30 mAh g^(−1)at the current densities from 100 mA g^(−1)to 1000 mA g^(−1),and when the current density is restored to 100 mA g^(−1),the specific capacity gradually recovered to 178.6 mAh g^(−1),which showed better rate performance and ultra-high cycling stability.This work highlights how the introduction of CuS into CoS nanostructures can benefit the reversibility and cyclicity of the magnesium storage reaction and offers an original and practical route for the modification of RMBs electrode materials with good electrochemical properties.
基金supported by grants from the National Natural Science Foundation of China(Nos.31971106,BWS21L013,and 21WS09002).
文摘Bone defects have serious economic and clinical impacts;however,despite improvements in bone defect management,the range of clinical outcomes remains limited.A variety of biomaterials have been used to treat complex bone defects.However,final bone repair outcomes may be adversely affected by poor osteogenic capacity and risk of infection.Consequently,therapeutic methods are required that reduce bacterial contamination and increase the use of osteogenic biomaterials.Herein,we report the preparation of poly(lactic acid-coglycolic acid)(PLGA)microspheres coloaded with magnesium(Mg^(2+))and gallium(Ga^(3+))ions(Mg-Ga@PLGA),which can fill irregular bone defects and show good biosafety.During in vitro testing,Mg-Ga@PLGA not only showed a synergistic effect on promoting osteogenic differentiation but also inhibited osteoclastic differentiation.Moreover,we found that Mg-Ga@PLGA demonstrated an antibacterial effect.During in vivo testing,Mg Ga@PLGA exhibited strong in situ osteogenic ability.In conclusion,Mg-Ga@PLGA has good potential for treating bone defects at risk of infection.
文摘Carbon-based materials have gained significant attention in anticancer treatment because of their exceptional biocompatibility,yet critical challenges persist in establishing definitive correlations between their porous structures and functional performance.We report the use of a silica template to guide pore formation in the design of mesoporous carbon spheres(mC)with tailored pore structures for improved combined photothermal-chemotherapy.The mesopore size of mC has been adjusted by kinetic control of the resin polymerization and silica hydrolysis.Structural characterization showed that 4.4 nm mesopores enabled an exceptional gemcitabine loading of 228 mg g^(−1) and a sustained pH/thermal dual-responsive release with>70%drug release under near-infrared(NIR)irradiation.Finite element analysis demonstrated pore size-dependent heat transfer dynamics,with the improved mC achieving a superior photothermal conversion efficiency of 62%by a combination of N-doping and defect engineering.In vitro evaluations confirmed outstanding biocompatibility with>95%cell viability at 200μg mL^(−1) and potent tumor suppression in pancreatic and biliary cancer models with an~5%cell viability at 25μg mL^(−1) where combined therapy showed a 3.7-fold increased cytotoxicity over monotherapy.The improved structure of mC facilitated cascade therapeutic effects with enhanced tumor permeability derived from NIR-triggered hyperthermia and prolonged therapeutic exposure due to pH-responsive drug release.This pore engineering strategy establishes a structure-function process for next-generation theranostic platforms,addressing the critical limitations of conventional pancreatic and biliary cancer therapies through spatiotemporal control of multimodal treatment.
基金Project(2023YFB4606200)supported by the National Key Research and Development Program of ChinaProject(2023-SSRF-HZ-503114-2)supported by Shanghai Synchrotron Radiation Facility,Instrument BL16U2,China。
文摘This comprehensive study investigates the formation and evolution of intermetallic compounds during the solidification process of magnesium alloys using advanced micro X-ray computed tomography.By analyzing both common industrial Mg-Al-Zn alloys and a novel rare earth-containing Mg-Ni-Gd-Y alloy,we aim to characterize the nucleation,growth,and distribution of Al-Mn and eutectic intermetallics across various stages of solidification.The non destructive imaging technique employed in this research provides high-resolution,three-dimensional insights into the microstructural development,allowing for a detailed examination of the morphology,spatial arrangement,and interconnectivity of intermetallic phases.This approach overcomes limitations of traditional two-dimensional metallographic methods,offering a more comprehensive understanding of the complex three-dimensional structures formed during solidification.
基金supported by the National Natural Science Foundation of China(No.52064035)the Key Research and Development Program of Gansu Province,China(No.25YFGA024)the Natural Science Foundation of Zhejiang Province,China(No.LGG22E020003).
文摘Lithium-sulfur(Li-S)batteries boast a theoretical energy density as high as 2600 Wh·kg^(−1),positioning them as a highly attractive option for future advanced energy storage systems.Challenges such as slow transformation kinetics and shuttle effects associated with lithium polysulfides(LiPSs)have seriously hindered their practical applications.In this paper,we present a new method for the synthesis of hollow carbon-sphere-supported Co monatomic catalysts(Co-N-C).This new synthesis method achieves pyrolytic coordination using a precursor rich in imide(-RC=N-)polymers.This synthesis method not only improves the adsorbability and catalytic activity of LiPS but also significantly weakens the shuttle effect and generates Co-N-C with superior conductivity,abundant hollow structures,and a high specific surface area,thus efficiently capturing and restricting the movement of LiPS intermediates.The dispersed Co monoatomic catalysts(Co SACs)were anchored to a highly conductive nitrogen-doped carbon framework and exhibited symmetric N-coordination active sites(Co-N_(4))to ensure fast redox kinetics of LiPS and Li_(2)S_(2)/Li_(2)S solid-state products.The lithium-sulfur battery with Co-N-C as the sulfur carrier showed excellent discharging capacity of 1146.6 mAh·g^(−1) at a discharge rate of 0.5 C and maintained excellent performance at a high discharge rate of 2 C.The capacity decay rate in 500 cycles was only 0.086%per cycle,reflecting excellent long-term cycle stability.This study highlights the key role of the synergistic effect between single-atom cobalt catalysts and hollow carbon spheres in enhancing the efficiency of lithium-sulfur(Li-S)batteries.It also provides valuable insights into the construction and fabrication of highly active monatomic catalysts.The catalytic conversion efficiency of lithium polysulfides is significantly enhanced when embedded in hollow carbon architectures,which serves as a critical strategy for optimizing the electrochemical behavior of next-generation Li-S batteries.
基金supported by the National Key R&D Program of China (No.2022YFB3803703)the National Natural Science Foundation of China (Nos.52071141,52271212,52201250,51771056,22305104)+1 种基金the Natural Science Foundation of Jiangsu Province (No.BK20210893)the Ministry of Science and Technology of the People’s Republic of China (No.G2023014022L)。
文摘Magnesium hydride(MgH_(2)) demonstrates immense potential as a solid-state hydrogen storage material,while its commercial utilization is impeded by the elevated operating temperature and sluggish reaction kinetics.Herein,a MOF derived multi-phase FeNi_(3)-S catalyst was specially designed for efficient hydrogen storage in MgH_(2).Experiments confirmed that the incorporation of FeNi_(3)-S into MgH_(2) significantly lowered the desorption temperature and accelerated the kinetics of hydrogen desorption and reabsorption.The initial dehydrogenation temperature of the MgH_(2)+10 wt% FeNi_(3)-S composite was 202 ℃,which was 123 ℃ lower than that of pure MgH_(2).At 325 ℃,the MgH_(2)+10 wt% FeNi_(3)-S composite released 6.57 wt% H_(2)(fully dehydrogenated) within 1000 s.Remarkably,MgH_(2)+ 10 wt% FeNi_(3)-S composite initiated rehydrogenation at room temperature and rapidly absorbed 2.49 wt% H_(2) within 30 min at 100 ℃.Moreover,6.3 wt% H_(2) was still retained after 20 cycles at 300 ℃,demonstrating the superior cycling performance of the MgH_(2)+10 wt% FeNi_(3)-S composite.The activation energy fitting calculations further evidenced the addition of FeNi_(3)-S enhanced the de/resorption kinetics of MgH_(2)(E_(a)= 98.6 k J/mol and 43.3 k J/mol,respectively).Through phase and microstructural analysis,it was determined that the exceptional hydrogen storage performance of the composite was attributed to the in-situ formation of Mg/Mg_(2)Ni + Fe/MgS and MgH_(2)/Mg_(2)NiH_(4)+Fe/MgS hydrogen storage systems.Further mechanistic analysis revealed that Mg_(2)Ni/Mg_(2)NiH_(4) served as “hydrogen pump” and Fe/Mg S served as “hydrogen diffusion channel”,thus accelerating the dissociation and recombination of hydrogen molecules.In conclusion,this work offers insight into catalysts combining transition metal alloys and transition metal sulfide for exerting muti-phase synergistic effect on boosting the dehydrogenation/hydrogenation reactions of MgH_(2),which can also inspire future pioneering work on designing and fabricating high efficient catalysts in other energy storage related areas.
基金supported by the Guangxi Natural Science Foundation,China(No.2020GXNSFAA 159011)the National Natural Science Foundation of China(No.51664011).
文摘Magnesium-based anode materials have attracted significant attention in the energy storage domain because of their high theoretical capacities and low electrochemical potentials.However,in conventional electrolyte systems,magnesium metal electrodes dynamically generate an ion-blocking surface layer,resulting in prominent voltage polarization,which severely limits their practical applications.In this study,ZIF-8/carbon nanotubes(CNTs)coatings were used to modify the anodes of magnesium batteries.Compared with the unaltered magnesium battery,the voltage lag time of the ZIF-8/CNTs coating was shortened from 4 s before modification to 0.26 s,and the battery impedance was lowered by two orders of magnitude.The duration of the discharge platform was increased from 4 h before modification to 6-10 h,the anode utilization rate was more than doubled,and the specific energy density was significantly enhanced compared with the battery before modification.The mechanism indicates that the ZIF-8/CNTs coating can limit the infiltration of corrosive substances,extend their transmission path,and offer more effective protection to the magnesium anode.The incorporation of CNTs improves the conductivity of the battery,and it significantly improves the electrochemical performance of the magnesium battery.
基金supported by the National Natural Science Foundation of China(62201602)。
文摘Despite the superior advantages of specific emitter identification in extracting emitter features from in-phase and quadrature(I/Q)signals,challenges persist due to signal-type confusion and background noise interference.To address those limitations,this paper proposes a multi-channel contrast prediction coding and complex-valued residuals network(MCPC-MCVResNet)framework.This model employs contrast prediction techniques to directly extract discriminative features from electromagnetic signal sequences,effectively capturing both amplitude and phase information within I/Q data.A core innovation of this approach is the sphere space softmax(SS-softmax)loss,which optimizes intra-class clustering density of while establishing well-defined boundaries between distinct emitters.The SS-softmax mechanism significantly enhances the model's capacity to discern subtle variations among radiation emitters.Experimental results demonstrate superior identification accuracy,rapid convergence,and exceptional robustness in low signal-to-noise ratio environments.
基金supported by the National Key R&D Program of China(No.2023YFB3809500)the Fundamental Research Funds for the Central Universities(No.2024CDJXY003)+1 种基金the Venture&Innovation Support Program for Chongqing Overseas Returnees(cx2023087)The Chongqing Technology Innovation and Application Development Project(No.2024TIAD-KPX0003).
文摘Micro-sized anatase TiO_(2) displays inferior capacity as cathode material for magnesium ion batteries because of the higher diffusion energy barrier of Mg^(2+)in anatase TiO_(2) lattice.Herein,we report that nanosized anatase TiO_(2) exposed(001)facet doubles the capacity compared to the micro-sized sample ascribed to the interfacial Mg^(2+)ion storage.First-principles calculations reveal that the diffusion energy barrier of Mg^(2+)on the(001)facet is significantly lower than those in the bulk phase and on(100)facet,and the adsorption energy of Mg^(2+)on the(001)facet is also considerably lower than that on(100)facet,which guarantees superior interfacial Mg^(2+)storage of(001)facet.Moreover,anatase TiO_(2) exposed(001)facet displays a significantly higher capacity of 312.9 mAh g^(−1) in Mg-Li dual-salt electrolyte compared to 234.3 mAh g^(−1) in Li salt electrolyte.The adsorption energies of Mg^(2+)on(001)facet are much lower than the adsorption energies of Li+on(001)facet,implying that the Mg^(2+)ion interfacial storage is more favorable.These results highlight that controlling the crystal facet of the nanocrystals effectively enhances the interfacial storage of multivalent ions.This work offers valuable guidance for the rational design of high-capacity storage systems.
基金Project (SJ08-ZT05) supported by the Natural Science Basic Research Plan in Shaanxi Province of ChinaProject (ZK1050) supported by the Key Scientific Research Plan of Baoji University of Arts and Science, China
文摘The oxidation behaviour of molten ZK60 and ME20 magnesium alloys in 1% 1,1,1,2-tetrafluoroethane/air atmospheres at 720 °C was compared with that of molten magnesium. The oxidation kinetics of these three melts was determined by thermograyimetric measuring instrument, and the surface films of the oxidized samples were examined by scanning electron microscope (SEM), X-ray diffractometry (XRD) and X-ray photoelectron spectroscopy (XPS). The results show that the oxidation rate of molten ZK60 or ME20 alloys is much lower than that of molten magnesium in 1% 1,1,1,2-tetrafluoroethane/air atmospheres. The surface film formed on the molten magnesium is composed of MgF2, MgO and C, while the film formed on ZK60 melt mainly consists of MgF2, MgO, C and some ZrF4, and the film on ME20 mainly consists of MgF2, MgO, C and a small amount of CeF4. The good oxidation resistances of ZK60 and ME20 alloy melts may be caused by their major alloying elements Zr and Ce, respectively.
基金the support from the Fundamental Research Funds for the Central Universities of Chongqing University(No.2020CDCGCL005)。
文摘Rechargeable magnesium batteries(RMBs),as one of the most promising candidates for efficient energy storage devices with high energy,power density and high safety,have attracted increasing attention.However,searching for suitable cathode materials with fast diffusion kinetics and exploring their magnesium storage mechanisms remains a great challenge.Cu S submicron spheres,made by a facile low-temperature synthesis strategy,were applied as the high-performance cathode for RMBs in this work,which can deliver a high specific capacity of 396mAh g^(-1)at 20 mA g^(-1) and a remarkable rate capacity of 250 m Ah g^(-1)at 1000 mA g^(-1).The excellent rate performance can be assigned to the nano needle-like particles on the surface of Cu S submicron spheres,which can facilitate the diffusion kinetics of Mg^(2+).Further storage mechanism investigations illustrate that the Cu S cathodes experience a two-step conversion reaction controlled by diffusion during the electrochemical reaction process.This work could make a contribution to the study of the enhancement of diffusion kinetics of Mg2+and the reaction mechanism of RMBs.
基金supported by the Specialized Research Fund for the Doctoral Program of Higher Education under Grant No.20090002110029the High Technology Research and Development Program of China under Grant No.2009AA03Z114the MOST(Ministry of Science and Technology)of China under Grant No.2010DFA72760
文摘Surface films that formed on molten AZ91D magnesium alloy in S02/air cover gases at 680 ℃ in a sealed furnace were characterized by scanning electron microscopy, energy dispersive spectroscopy, X-ray diffraction and Auger electron spectroscopy. It is revealed that the film formed on molten AZ91D alloy surface in cover gas with high air content can prevent the molten AZ91D alloy from oxidation and ignition. The surface film contained three elements, namely magnesium, oxygen and sulfur, and was mainly composed of MgO and MgS. The properties of the film depended on air content in the cover gas and holding time. Thermodynamic calculation showed that MgSO4 was the stable phase, and it was concluded that the formation of MgS04 was important for the formation of the protective surface film in S02/air atmospheres.
基金support from the National Natural Science Foundation of China(grant number 52075544)Innovation Funds of Jihua Laboratory(X220971UZ230)+1 种基金Basic and Applied Basic Research Foundation of Guangdong Province(2022A1515110649)Funds from Research Platforms of Guangdong Higher Education Institutes(2022ZDJS038).
文摘Efficient lubrication of magnesium alloys is a highly challenging topic in the field of tribology.In this study,magnesium silicate hydroxide(MSH)nanotubes with serpentine structures were synthesized.The tribological behavior of AZ91D magnesium alloy rubbed against GCr15 steel was studied under lubricating oil with surface-modified MSH nanotubes as additives.The effects of the concentration,applied load,and reciprocating frequency on the friction and wear of the AZ91D alloy were studied using an SRV-4 sliding wear tester.Results show a decrease of 18.7–68.5%in friction coefficient,and a reduction of 19.4–54.3%in wear volume of magnesium alloy can be achieved by applying the synthetic serpentine additive under different conditions.A suspension containing 0.3 wt.%MSH was most efficient in reducing wear and friction.High frequency and medium load were more conducive to improving the tribological properties of magnesium alloys.A series of beneficial physical and chemical processes occurring at the AZ91D alloy/steel interface can be used to explain friction and wear reduction based on the characterization of the morphology,chemical composition,chemical state,microstructure,and nanomechanical properties of the worn surface.The synthetic MSH,with serpentine structure and nanotube morphology,possesses excellent adsorbability,high chemical activity,and good self-lubrication and catalytic activity.Therefore,physical polishing,tribochemical reactions,and physicalchemical depositions can occur easily on the sliding contacts.A dense tribolayer with a complex composition and composite structure was formed on the worn surface.Its high hardness,good toughness and plasticity,and prominent lubricity resulted in the improvement of friction and wear,making the synthetic MSH a promising efficient oil additive for magnesium alloys under boundary and mixed lubrication.
基金supported by Natural Science Foundation of Hunan Province(2021JJ31081,2024JJ5619)the Science Fund of State Key Laboratory of Advanced Design and Manufacturing Technology for Vehicle(No 32215004).
文摘Biliary system,which is responsible for transporting bile from the liver into the intestine,is commonly damaged by inflammation or tumors eventually causing liver failure or death.The implantation of biliary stents can effectively alleviate both benign and malignant biliary strictures,but the plastic and metal stents that are currently used cannot degrade and nearly has no beneficial biological effects,therefore their long-term service can result into inflammation,the formation of sludges and re-obstruction of bile duct.In recent years,magnesium(Mg)metal has been received increasing attention in the field of biomedical application due to its excellent biocompatibility,adequate mechanical properties,biodegradability and other advantages,such as anti-inflammatory and anti-tumor properties.The research on biliary stents made of magnesium metals(BSMM)has also made significant progress and a series of experiments in vitro and vivo has proved their possibility.However,there are still some problems holding back BSMM’s clinical use,including rapid corrosion rate and potential harmful reaction.In this review,we would summarize the current research of BSMM,evaluate their clinical benefits,find the choke points,and discuss the solving method.
基金financially supported by the Natural Science and Engineering Technology in Qinghai Province(2023)the Qinghai Province"Kunlun Talents"High end Innovation and Entrepreneurship Talent Project(2023)+4 种基金the Western Young Scholars Program of Chinese Academy of Sciences(20242022000018)the National Natural Science Foundation of China(52404189)the Open Fund of Key Laboratory of Green and High-end Utilization of Salt Lake Resources(ISL2024-15)the Independent deployment project of the Qinghai Salt Lake Research Institute,CAS(E455HX3501)。
文摘Magnesium phosphate cements(MPC)have shown promising applications in many fields,but high raw material prices hinder their development.The production of salt lake MPC(SLMPC)from magnesium slag(MS),a byproduct of lithium extraction from salt lakes,offers significant environmental and economic advantages.In this study,a low-cost magnesia raw material was obtained through the calcination of MS,which was subsequently utilized in conjunction with KH_(2)PO_(4) to prepare SLMPC.The changes in hydration products,microscopic morphology,solution pH value,and TG content during the SLMPC curing process,and the hydration kinetics equation and model were used to study the hydration processes of SLMPC.The results show that the outcome indicates that the SLMPC system entered the accelerated reaction stage within 6 min after mixing,where the highest heat release rate was 6.29 J·g^(-1)·min^(-1),the maximum heat release was 205.3 J·g^(-1),and the main hydration product appeared at 50-60 min.The hydration behavior of SLMPC exhibits similarities to that of traditional MPC.Specifically,the acceleration phase is governed by an autocatalytic reaction,the deceleration phase is influenced by both autocatalytic reactions and diffusion processes,and the stabilization phase is predominantly controlled by diffusion mechanisms.This paper aims to establish the theoretical foundation for the industrial application of MS and the cost-effective production of MPC.
基金funded by Natural Science Foundation of Xinjiang Uygur Autonomous Region(2022D01F60)Tianshan Talents Plan of Xinjiang Uygur Autonomous Region(2022TSYCJC0001)+2 种基金National Natural Science Foundation of China(22368051)Science and Technology Plan Project of Karamay(20232023hjcxrc0038 and 2024hjcxrc0118)Projects of Talents Recruitment of GDUPT(2023rcyj2005)。
文摘In the extraction of potassium from salt lakes,Mg is abundant in the form of bischofite(MgCl_(2)·6H_(2)O),which is not utilized effectively,resulting in the waste of resources and environmental pressure.Anhydrous MgCl_(2) prepared by the dehydration of bischofite is a high-quality raw material for the production of Mg.However,direct calcination of MgCl_(2)·6H_(2)O in industrial dehydration processes leads to a large amount of hydrolysis.The by-products are harmful to the electrolysis process of Mg,causing problems such as sludge formation,low current efficiency,and corrosion in the electrodes.To obtain high-purity anhydrous MgCl_(2),different advanced dehydration processes have been proposed.In this review,we focus on the recent progress of the dehydration process.Firstly,we discuss the molecular structure of MgCl_(2)·6H_(2)O and explain the reason why much hydrolysis occurs in dehydration.Secondly,we introduce the specific dehydration processes,mainly divided into direct dehydration processes and indirect dehydration processes.The direct dehydration processes are classified into gas protection heating and molecular sieve dehydration process.Indirect dehydration processes are classified into thermal dehydration of ammonium carnallite(NH_(4)Cl·MgCl_(2)·6H_(2)O),thermal dehydration of potassium carnallite(KCl·MgCl_(2)·6H_(2)O),thermal decomposition of the[HAE]Cl·MgCl_(2)·6H_(2)O,organic solvent distillation,ionic liquid dehydration process and ammonia complexation process.In the meanwhile,purity of anhydrous MgCl_(2) of each dehydration process,as well as the advantages and disadvantages,is discussed.The characteristics of different processes with a simple economic budget are also given in this paper.Finally,the main challenges are evaluated with suggested directions in the future,aiming to guide the synthesis of high-purity anhydrous MgCl_(2).
基金supported by the National Natural Science Foundation of China(Nos.51825101,52001202)the National Key Research and Development Program of China(No.2021YFA1600900)。
文摘A comprehensive analysis of the microstructure and defects of a thixomolded AZ91D alloy was conducted to elucidate their influences on mechanical properties.Samples were made at injection temperatures ranging from 580 to 640℃.X-ray computed tomography was used to visualize pores,and crystal plasticity finite element simulation was adopted for deformation analysis.The microstructure characterizations reveal a hierarchical cell feature composed of α-Mg and eutectic phases.With the increase of injection temperature,large cell content in the material decreases,while the strength of the alloy increases.The underlying mechanism about strength change is that coarse-grained solids experience smaller stress even in hard orientations.The sample fabricated at a moderate temperature of 620℃ exhibits the highest elongation,least quantity and lower local concentration of pores.The detachment and tearing cracks formed at lower injection temperature and defect bands formed at higher injection temperature add additional crack sources and deteriorate the ductility of the materials.
基金supported by the National Natural Science Found for Distinguished Young Scholars(52225101)the Fundamental Research Funds for the Central Universities(WUT:104972024RSCbs0018 and 2023CDJYXTD-002)+1 种基金the Natural Science Foundation of Chongqing(CSTB2023NSCQ-MSX0527)the Chongqing Academician Special Fund(2022YSZXJCX0014CSTB).
文摘As one of the lightest engineering materials,magnesium(Mg)alloy possesses excellent mechanical performance,meeting the needs of versatile engineering fields and holding the potential to address cutting-edge issues in aerospace,electronics,biomedicine.The design of superhydrophobic(SHB)surfaces with micro and nanostructures can endow Mg alloys with multiple functionalities,such as self-cleaning,self-healing,antibacterial,and corrosion resistance.Over the past decade,researchers have drawn inspiration from nature to implement biomimetic design principles,resulting in the rapid development of micro/nanostructured SHB surfaces on Mg alloys,which hold great promise for biomedical applications.This review comprehensively introduces the biomimetic design principles of micro/nanostructured SHB surfaces on Mg alloys,discusses the challenges along with advantages and disadvantages of current preparation methods,and explores the future perspectives for preparing these SHB surfaces,providing strategies to enhance their performance in biomedical applications.
基金the National Key Research and Development Program of China(2022YFB3504503)the National Natural Science Foundation of China(52274355)the Gansu Province Science and Technology Major Special Project,China(22ZD6GD061).
文摘Precipitation is often used for the preparation of La(OH)_(3)with precipitants of liquid alkali and ammonia.To solve the problems of high cost and wastewater pollution caused by common precipitants,the active MgO synthesized by pyrolysis was used as the precipitant to prepare La(OH)_(3).The species distribution of LaCl_(3)and LaCl_(3)-MgCl_(2)mixed system solution was calculated,and the kinetic analysis of the precipi-tation process was carried out to confirm the key factors influencing the precipitation of La(OH)_(3).The results show that La(OH)_(3)with D_(50)of 5.57μm,a specific surface area of 25.70 m^(2)/g,a rod-like shape,and MgO content of 0.044 wt%,was successfully prepared by adding active MgO.The precipitation ratio of La reaches 99.92%.The La(OH)_(3)precipitation is controlled by the diffusion process.The activity of MgO has a significant influence on MgO content in the precipitate.The preparation of La(OH)_(3)by active MgO provides a potential way for an eco-friendly preparation method of rare earth.
文摘Magnesium(Mg)-based bioresorbable stents represent a potentially groundbreaking advancement in cardiovascular therapy;offering tem-porary vessel support and complete biodegradability—addressing limitations of traditional stents like in-stent restenosis and long-term com-plications.However,challenges such as rapid corrosion and suboptimal endothelialisation have hindered their clinical adoption.This review highlights the latest breakthroughs in surface modification,alloying,and coating strategies to enhance the mechanical integrity,corrosion resistance,and biocompatibility of Mg-based stents.Key surface engineering techniques,including polymer and bioactive coatings,are ex-amined for their role in promoting endothelial healing and minimising inflammatory responses.Future directions are proposed,focusing on personalised stent designs to optimize efficacy and long-term outcomes,positioning Mg-based stents as a transformative solution in interventional cardiology.
