Eutrophication is a significant challenge for surface water,with sediment phosphorus(P)release being a key contributor.Although biological aluminum-based P-inactivation agent(BA-PIA)has shown effectiveness in controll...Eutrophication is a significant challenge for surface water,with sediment phosphorus(P)release being a key contributor.Although biological aluminum-based P-inactivation agent(BA-PIA)has shown effectiveness in controlling P release from sediment,the efficiency and mechanism by BA-PIA capping is still not fully understood.This study explored the efficiency and mechanism of using BA-PIA capping controlling P release from sediment.The main mechanisms controlling P release from sediment via BA-PIA capping involved transforming mobile and less stable fractions into stable ones,passivating DGT-labile P and establishing a 13 mm’P static layer’within the sediment.Additionally,BA-PIA’s impact on Fe redox processes significantly influenced P release from the sediment.After BA-PIA capping,notable reductionswere observed in total P,soluble reactive P(SRP),and diffusive gradient in thin-films(DGT)-measured labile P(DGT-labile P)concentration in the overlying water,with reduction rates of 95.6%,92.7%,and 96.5%,respectively.After BA-PIA capping,the diffusion flux of SRP across the sediment-water interface and the apparent P diffusion flux decreased by 91.3%and 97.8%,respectively.Additionally,BA-PIA capping led to reduced concentrations of SRP,DGT-labile P,and DGT-measured labile Fe(II)in the sediment interstitial water.Notably,BA-PIA capping significantly reduced P content and facilitated transformation in the 0∼30 mm sediment layers but not in the 30∼45 mm and 45∼60 mm sediment layers for NaOH-extractable inorganic P and HCl-extracted P.These findings offer a theoretical basis and technical support for the practical application of BA-PIA capping to control P release from sediment.展开更多
In this study,aluminum-based P-inactivation agent(Al-PIA)was used as a high-efficiency microbial carrier,and the biological Al-PIA(BA-PIA)was prepared by artificial aeration.Laboratory static experiments were conducte...In this study,aluminum-based P-inactivation agent(Al-PIA)was used as a high-efficiency microbial carrier,and the biological Al-PIA(BA-PIA)was prepared by artificial aeration.Laboratory static experiments were conducted to study the effect of BA-PIA on reducing nitrogen and phosphorus contents in water.Physicochemical characterization and isotope tracing method were applied to analyze the removal mechanism of nitrogen and phosphorus.High-throughput techniques were used to analyze the characteristic bacterial genus in the BA-PIA system.The nitrogen and phosphorus removal experiment was conducted for 30 days,and the removal rates of NH_(4)^(+)-N,TN and TP by BA-PIA were 81.87%,66.08%and 87.97%,respectively.The nitrogen removal pathways of BA-PIA were as follows:the nitrification reaction accounted for 59.0%(of which denitrification reaction accounted for 56.4%),microbial assimilation accounted for 18.1%,and the unreacted part accounted for 22.9%.The characteristic bacteria in the BA-PIA system were Streptomyces,Nocardioides,Saccharopolyspora,Nitrosomonas,and Marinobacter.The loading of microorganisms only changed the surface physical properties of Al-PIA(such as specific surface area,pore volume and pore size),without changing its surface chemical properties.The removal mechanism of nitrogen by BA-PIA is the conversion of NH_(4)^(+)-N into NO_(2)^(−)-N and NO_(3)^(−)-N by nitrifying bacteria,which are then reduced to nitrogen-containing gas by aerobic denitrifying bacteria.The phosphorus removal mechanism is that metal compounds(such as Al)on the surface of BA-PIA fix phosphorus through chemisorption processes,such as ligand exchange.Therefore,BA-PIA overcomes the deficiency of Al-PIA with only phosphorus removal ability,and has better application prospects.展开更多
Measuring the dust explosion characteristics of aluminum-based activated fuels was a prerequisite for developing effective prevention and control measures.In this paper,ignition sensitivity,flame propagation behaviors...Measuring the dust explosion characteristics of aluminum-based activated fuels was a prerequisite for developing effective prevention and control measures.In this paper,ignition sensitivity,flame propagation behaviors and explosion severity of aluminum/polytetrafluoroethylene(Al/PTFE)compositions including 2 PT(2.80 wt.%F),4 PT(7.18 wt.%F)and 8 PT(11.90 wt.%F)were studied.When the content of F increased from 2.80 wt.%to 11.90 wt.%,the minimum explosive concentration MEC decreased from380 g/m^(3)to 140 g/m^(3),due to the dual effects of increased internal active aluminum and enhanced reactivity.The average flame propagation velocities increased as the percentage of F increased.The maximum explosion pressure Pmof 500 g/m3aluminum-based activated fuels increased from 247 k Pa to299 kPa.Scanning electron microscopy demonstrated that with the increase of PTFE content,the reaction was more complete.On this basis,the explosion mechanism of aluminum-based activated fuels was revealed.展开更多
To improve the thermal properties of aluminum(Al)in the energetic system,a coated structure with ammonium perchlorate(AP)was prepared by a facile approach.And N,N-Dimethylformamide(DMF)was chosen as an ideal solvent b...To improve the thermal properties of aluminum(Al)in the energetic system,a coated structure with ammonium perchlorate(AP)was prepared by a facile approach.And N,N-Dimethylformamide(DMF)was chosen as an ideal solvent based on heterogeneous nucleation theory and molecular dynamics simulation.This coated structure could enlarge the contact area and improve the reaction environment to enhance the thermal properties.The addition of AP could accelerate oxidation temperature of Al with around 17.5°C.And the heat release of 85@15 composition rises to 26.13 k J/g and the reaction degree is97.6%with higher peak pressure(254.6 k Pa)and rise rate(1.397 MPa/s).An ideal ratio with 15 wt%AP was probed primarily.The high energy laser-induced shockwave experiment was utilized to simulate the reaction behavior in hot field.And the larger activated mixture of coated powder could release more energy to promote the growth of shockwave with higher speed up to 518.7±55.9 m/s.In conclusion,85@15 composition is expected to be applied in energetic system as a novel metal fuel.展开更多
Protecting clusters from coalescing by ligands has been universally adopted in the chemical synthesis of atomically precise clusters.Apart from the stabilization role,the effect of ligands on the electronic properties...Protecting clusters from coalescing by ligands has been universally adopted in the chemical synthesis of atomically precise clusters.Apart from the stabilization role,the effect of ligands on the electronic properties of cluster cores in constructing superatoms,however,has not been well understood.In this letter,a comprehensive theoretical study about the effect of an organic ligand,methylated N-heterocyclic carbene(C_(5)N_(2)H_(8)),on the geometrical and electronic properties of the aluminum-based clusters XAl_(12)(X=Al,C and P)featuring different valence electron shells was conducted by utilizing the density functional theory(DFT)calculations.It was observed that the ligand can dramatically alter the electronic properties of these aluminum-based clusters while maintaining their structural stability.More intriguingly,different from classical superatom design strategies,the proposed ligation strategy was evidenced to possess the capability of remarkably reducing the ionization potentials(IP)of these clusters forming the ligated superalkalis,which is regardless of their shell occupancy.The charge transfer complex formed during the ligation process,which regulates the electronic spectrum through the electrostatic Coulomb potential,was suggested to be responsible for such an IP drop.The ligation strategy highlighted here may provide promising opportunities in realizing the superatom synthesis in the liquid phase.展开更多
The computational crystallography is proposed. Its basic concept and research method are systematically introduced, with aluminum-based spinel (ABS) as an example, through (i) selecting basic crystal structural unit, ...The computational crystallography is proposed. Its basic concept and research method are systematically introduced, with aluminum-based spinel (ABS) as an example, through (i) selecting basic crystal structural unit, (ii) determining the mathematical expression of crystal structure, (iii) computing the stability energy of growth unit and finding out which is (are) favorable one(s), and (iv) describing the formation process of crystal morphology. The morphology of ABS deduced from the computation is in excellent agreement with that from hydrothermal experiments.展开更多
An analytical solution was used to investigate the elastic response of a sandwich beam with a graphene-reinforced aluminum-based composite(GRAC)on an elastic foundation using copper as the face layer of the functional...An analytical solution was used to investigate the elastic response of a sandwich beam with a graphene-reinforced aluminum-based composite(GRAC)on an elastic foundation using copper as the face layer of the functionally graded composite beam and a simply supported boundary condition.Mantari's higher-order shear deformation theory was utilized to derive the equations,which were solved in Laplace space and then converted into space–time using Laplace inversion.The exact response of the GRAC sandwich beam was obtained by considering the displacement at the mid-span of the sandwich beam.Two moving loads with different speed ratios were applied at a single point,and the effect of various parameters,including the spring constant,the speed ratio,the percentage of graphene,the moving load speed,and the distribution pattern,was investigated.This study aimed to eliminate any overlap and improve the accuracy of the results.The exact solving method presented has not been reported in other articles so far.Additionally,due to the difficulty of solving mathematical equations,this method is only applicable to simple boundary conditions.展开更多
Two-dimensional layered aluminum-based adsorbents have been developed and successfully applied to enrich low-concentration lithium from shale gas produced water.The adsorbent,synthesized with a lithium-to-aluminum mol...Two-dimensional layered aluminum-based adsorbents have been developed and successfully applied to enrich low-concentration lithium from shale gas produced water.The adsorbent,synthesized with a lithium-to-aluminum molar ratio of 0.6 in the salt solution,demonstrated exceptional performance characteristics.Its structure,featuring nano-encapsulated layers,facilitated lithium insertion,enhanced the surface area,and optimized pore size distribution for efficient adsorption.The adsorption equilibrium was reached within 60 min,closely aligning with the pseudo-second-order model.The isotherm analysis,based on the Sips model,suggested a nonhomogeneous multilayer adsorption process.Additionally,the adsorbent showed exceptional selectivity for Li^(+)over Na^(+),Ca^(2+),and Mg^(2+),ensuring effective lithium enrichment.Further desorption studies indicated that optimal conditions involved using deionized water at 333 K with a liquid-to-solid ratio of 80 mL/g.The adsorbent maintained robust performance and structural integrity through five adsorption-desorption cycles,highlighting its potential for recyclability and practical application in lithium recovery.These developments represent significant progress in harnessing lithium resources from shale gas produced water,thereby supporting advancements in clean energy technologies.展开更多
The electronic packaging box with high silicon aluminum-base alloy was prepared by semi-solid thixoforming technique.The flow characteristic of the Si phase was analyzed.The microstructures of different parts of the b...The electronic packaging box with high silicon aluminum-base alloy was prepared by semi-solid thixoforming technique.The flow characteristic of the Si phase was analyzed.The microstructures of different parts of the box were observed by optical microscopy and scanning electron microscopy,and the thermophysical and mechanical properties of the box were tested.The results show that there exists the segregation phenomenon between the primary Si phase and the liquid phase during thixoforming,the liquid phase flows from the box,and the primary Si phase accumulates at the bottom of the box.The volume fraction of primary Si phase decreases gradually from the bottom to the walls.Accordingly,the thermal conductivities of bottom center and walls are 107.6 and 131.5 W/（m·K）,the coefficients of thermal expansion（CTE） are 7.9×10-6 and 10.6×10-6 K-1,respectively.The flexural strength increases slightly from 167 to 180 MPa.The microstructures and properties of the box show gradient distribution overall.展开更多
The electronic packaging shell with high silicon carbide aluminum-base composites was prepared by semi-solid thixoforming technique. The flow characteristic of the Si C particulate was analyzed. The microstructures of...The electronic packaging shell with high silicon carbide aluminum-base composites was prepared by semi-solid thixoforming technique. The flow characteristic of the Si C particulate was analyzed. The microstructures of different parts of the shell were observed by scanning electron microscopy and optical microscopy, and the thermophysical and mechanical properties of the shell were tested. The results show that there exists the segregation phenomenon between the Si C particulate and the liquid phase during thixoforming, the liquid phase flows from the shell, and the Si C particles accumulate at the bottom of the shell. The volume fraction of Si C decreases gradually from the bottom to the walls. Accordingly, the thermal conductivities of bottom center and walls are 178 and 164 W·m-1·K-1, the coefficients of thermal expansion(CTE) are 8.2×10-6 and 12.6×10-6 K-1, respectively. The flexural strength decreases slightly from 437 to 347 MPa. The microstructures and properties of the shell show gradient distribution.展开更多
An Al-based composite reinforced with core–shell-structured Ti/Al_3Ti was fabricated through a powder metallurgy route followed by hot extrusion and was found to exhibit promising mechanical properties. The ultimate ...An Al-based composite reinforced with core–shell-structured Ti/Al_3Ti was fabricated through a powder metallurgy route followed by hot extrusion and was found to exhibit promising mechanical properties. The ultimate tensile strength and elongation of the composite sintered at 620°C for 5 h and extruded at a mass ratio of 12.75:1 reached 304 MPa and 14%, respectively, and its compressive deformation reached 60%. The promising mechanical properties are due to the core–shell-structured reinforcement, which is mainly composed of Al_3Ti and Ti and is bonded strongly with the Al matrix, and to the reduced crack sensitivity of Al_3Ti. The refined grains after hot extrusion also contribute to the mechanical properties of this composite. The mechanical properties might be further improved through regulating the relative thickness of Al–Ti intermetallics and Ti metal layers by adjusting the sintering time and the subsequent extrusion process.展开更多
Thermodynamic properties of Al-Ce-Mn and Al-Ce—Zn liquid systems were studied by direct equilibrium method at 700 and 800℃respectively.The results obtained include,equilibrium products,their standard Gibbs energies ...Thermodynamic properties of Al-Ce-Mn and Al-Ce—Zn liquid systems were studied by direct equilibrium method at 700 and 800℃respectively.The results obtained include,equilibrium products,their standard Gibbs energies of formation,equilibrium constants of reactions and activity interaction coefficients between Ce and Mn or Zn in liquid aluminum.展开更多
Thermodynamic properties of Al-Ce-Pb and Al-Ce-Sn liquid systems were studied by direct equilibrium method at 800℃. The results obtained include: equilibrium products, their standard Gibbs energies of formation, equi...Thermodynamic properties of Al-Ce-Pb and Al-Ce-Sn liquid systems were studied by direct equilibrium method at 800℃. The results obtained include: equilibrium products, their standard Gibbs energies of formation, equilibrium constants of reactions and activity interaction coefficients between Ce and Pb or Sn in liquid aluminum.展开更多
We determined the effects of quartz sand(QS),water treatment plant sludge(WTPS),aluminum-based P-inactivation agent(Al-PIA),and lanthanum-modified bentonite(LMB)thin-layer capping on controlling phosphorus and nitroge...We determined the effects of quartz sand(QS),water treatment plant sludge(WTPS),aluminum-based P-inactivation agent(Al-PIA),and lanthanum-modified bentonite(LMB)thin-layer capping on controlling phosphorus and nitrogen release from the sediment,using a static simulation experiment.The sediment in the experiment was sampled from Yundang Lagoon(Xiamen,Fujian Province,China),which is a eutrophic waterbody.The total phosphorus(TP),ammonium nitrogen(NH4+-N),and total organic carbon(TOC)levels in the overlying water were measured at regular intervals,and the changes of different P forms in WTPS,Al-PIA,and sediment of each system were analyzed before and after the test.The average TP reduction rates of LMB,Al-PIA,WTPS,and QS were 94.82,92.14,86.88,and 10.68%,respectively,when the release strength of sediment TP was 2.26–9.19 mg/(m^(2)·d)and the capping strength of the materials was 2 kg/m^(2).Thin-layer capping of LMB,WTPS,and Al-PIA could effectively control P release from the sediment(P<0.05).However,thin-layer capping of LMB,Al-PIA,and QS did not significantly reduce the release of ammonium N and organic matter(P>0.05).Based on our results,LMB,Al-PIA,and WTPS thin-layer capping promoted the migration and transformation of easily released P in sediment.The P adsorbed by WTPS and Al-PIA mainly occurred in the form of NAIP.展开更多
基金supported by the National Natural Science Foundation of China(No.51878300)the National Natural Science Foundation of Xiamen City(No.3502Z202373041)the Water Conservancy Science and Technology Plan Project(No.RC2127).
文摘Eutrophication is a significant challenge for surface water,with sediment phosphorus(P)release being a key contributor.Although biological aluminum-based P-inactivation agent(BA-PIA)has shown effectiveness in controlling P release from sediment,the efficiency and mechanism by BA-PIA capping is still not fully understood.This study explored the efficiency and mechanism of using BA-PIA capping controlling P release from sediment.The main mechanisms controlling P release from sediment via BA-PIA capping involved transforming mobile and less stable fractions into stable ones,passivating DGT-labile P and establishing a 13 mm’P static layer’within the sediment.Additionally,BA-PIA’s impact on Fe redox processes significantly influenced P release from the sediment.After BA-PIA capping,notable reductionswere observed in total P,soluble reactive P(SRP),and diffusive gradient in thin-films(DGT)-measured labile P(DGT-labile P)concentration in the overlying water,with reduction rates of 95.6%,92.7%,and 96.5%,respectively.After BA-PIA capping,the diffusion flux of SRP across the sediment-water interface and the apparent P diffusion flux decreased by 91.3%and 97.8%,respectively.Additionally,BA-PIA capping led to reduced concentrations of SRP,DGT-labile P,and DGT-measured labile Fe(II)in the sediment interstitial water.Notably,BA-PIA capping significantly reduced P content and facilitated transformation in the 0∼30 mm sediment layers but not in the 30∼45 mm and 45∼60 mm sediment layers for NaOH-extractable inorganic P and HCl-extracted P.These findings offer a theoretical basis and technical support for the practical application of BA-PIA capping to control P release from sediment.
基金supported by the National Natural Science Fund of China(No.51878300)the Natural Science Foundation of Fujian Province of China(No.2019J01052)the Science and Technology Project Foundation of Xiamen City(No.3502Z20203044).
文摘In this study,aluminum-based P-inactivation agent(Al-PIA)was used as a high-efficiency microbial carrier,and the biological Al-PIA(BA-PIA)was prepared by artificial aeration.Laboratory static experiments were conducted to study the effect of BA-PIA on reducing nitrogen and phosphorus contents in water.Physicochemical characterization and isotope tracing method were applied to analyze the removal mechanism of nitrogen and phosphorus.High-throughput techniques were used to analyze the characteristic bacterial genus in the BA-PIA system.The nitrogen and phosphorus removal experiment was conducted for 30 days,and the removal rates of NH_(4)^(+)-N,TN and TP by BA-PIA were 81.87%,66.08%and 87.97%,respectively.The nitrogen removal pathways of BA-PIA were as follows:the nitrification reaction accounted for 59.0%(of which denitrification reaction accounted for 56.4%),microbial assimilation accounted for 18.1%,and the unreacted part accounted for 22.9%.The characteristic bacteria in the BA-PIA system were Streptomyces,Nocardioides,Saccharopolyspora,Nitrosomonas,and Marinobacter.The loading of microorganisms only changed the surface physical properties of Al-PIA(such as specific surface area,pore volume and pore size),without changing its surface chemical properties.The removal mechanism of nitrogen by BA-PIA is the conversion of NH_(4)^(+)-N into NO_(2)^(−)-N and NO_(3)^(−)-N by nitrifying bacteria,which are then reduced to nitrogen-containing gas by aerobic denitrifying bacteria.The phosphorus removal mechanism is that metal compounds(such as Al)on the surface of BA-PIA fix phosphorus through chemisorption processes,such as ligand exchange.Therefore,BA-PIA overcomes the deficiency of Al-PIA with only phosphorus removal ability,and has better application prospects.
基金financially supported by National Natural Science Foundation of China(No.51922025 and No.51874066)China Postdoctoral Science Foundation(No.2020M670759)the Fundamental Research Funds for the Central Universities(No.DUT20GJ201)。
文摘Measuring the dust explosion characteristics of aluminum-based activated fuels was a prerequisite for developing effective prevention and control measures.In this paper,ignition sensitivity,flame propagation behaviors and explosion severity of aluminum/polytetrafluoroethylene(Al/PTFE)compositions including 2 PT(2.80 wt.%F),4 PT(7.18 wt.%F)and 8 PT(11.90 wt.%F)were studied.When the content of F increased from 2.80 wt.%to 11.90 wt.%,the minimum explosive concentration MEC decreased from380 g/m^(3)to 140 g/m^(3),due to the dual effects of increased internal active aluminum and enhanced reactivity.The average flame propagation velocities increased as the percentage of F increased.The maximum explosion pressure Pmof 500 g/m3aluminum-based activated fuels increased from 247 k Pa to299 kPa.Scanning electron microscopy demonstrated that with the increase of PTFE content,the reaction was more complete.On this basis,the explosion mechanism of aluminum-based activated fuels was revealed.
基金supported by National Natural Science Foundation of China[No.21975024]。
文摘To improve the thermal properties of aluminum(Al)in the energetic system,a coated structure with ammonium perchlorate(AP)was prepared by a facile approach.And N,N-Dimethylformamide(DMF)was chosen as an ideal solvent based on heterogeneous nucleation theory and molecular dynamics simulation.This coated structure could enlarge the contact area and improve the reaction environment to enhance the thermal properties.The addition of AP could accelerate oxidation temperature of Al with around 17.5°C.And the heat release of 85@15 composition rises to 26.13 k J/g and the reaction degree is97.6%with higher peak pressure(254.6 k Pa)and rise rate(1.397 MPa/s).An ideal ratio with 15 wt%AP was probed primarily.The high energy laser-induced shockwave experiment was utilized to simulate the reaction behavior in hot field.And the larger activated mixture of coated powder could release more energy to promote the growth of shockwave with higher speed up to 518.7±55.9 m/s.In conclusion,85@15 composition is expected to be applied in energetic system as a novel metal fuel.
基金supported by the Innovation Project of Jinan Science and Technology Bureau(No.2021GXRC032)the Taishan Scholars Project of Shandong Province(No.ts201712011)+4 种基金the National Natural Science Foundation of China(NSFC,Nos.92161101,21603119)the Natural Science Foundation of Shandong Province(No.ZR2020ZD35)the Shandong University Multidisciplinary Research and Innovation Team of Young Scholars(No.2020QNQT015)the Young Scholars Program of Shandong University(YSPSDU,No.2018WLJH48)the Fundamental Research Funds of Shandong University(No.2017TB003).
文摘Protecting clusters from coalescing by ligands has been universally adopted in the chemical synthesis of atomically precise clusters.Apart from the stabilization role,the effect of ligands on the electronic properties of cluster cores in constructing superatoms,however,has not been well understood.In this letter,a comprehensive theoretical study about the effect of an organic ligand,methylated N-heterocyclic carbene(C_(5)N_(2)H_(8)),on the geometrical and electronic properties of the aluminum-based clusters XAl_(12)(X=Al,C and P)featuring different valence electron shells was conducted by utilizing the density functional theory(DFT)calculations.It was observed that the ligand can dramatically alter the electronic properties of these aluminum-based clusters while maintaining their structural stability.More intriguingly,different from classical superatom design strategies,the proposed ligation strategy was evidenced to possess the capability of remarkably reducing the ionization potentials(IP)of these clusters forming the ligated superalkalis,which is regardless of their shell occupancy.The charge transfer complex formed during the ligation process,which regulates the electronic spectrum through the electrostatic Coulomb potential,was suggested to be responsible for such an IP drop.The ligation strategy highlighted here may provide promising opportunities in realizing the superatom synthesis in the liquid phase.
基金supported by the National Natural Science Foundation of China(Grant No.59832080).
文摘The computational crystallography is proposed. Its basic concept and research method are systematically introduced, with aluminum-based spinel (ABS) as an example, through (i) selecting basic crystal structural unit, (ii) determining the mathematical expression of crystal structure, (iii) computing the stability energy of growth unit and finding out which is (are) favorable one(s), and (iv) describing the formation process of crystal morphology. The morphology of ABS deduced from the computation is in excellent agreement with that from hydrothermal experiments.
文摘An analytical solution was used to investigate the elastic response of a sandwich beam with a graphene-reinforced aluminum-based composite(GRAC)on an elastic foundation using copper as the face layer of the functionally graded composite beam and a simply supported boundary condition.Mantari's higher-order shear deformation theory was utilized to derive the equations,which were solved in Laplace space and then converted into space–time using Laplace inversion.The exact response of the GRAC sandwich beam was obtained by considering the displacement at the mid-span of the sandwich beam.Two moving loads with different speed ratios were applied at a single point,and the effect of various parameters,including the spring constant,the speed ratio,the percentage of graphene,the moving load speed,and the distribution pattern,was investigated.This study aimed to eliminate any overlap and improve the accuracy of the results.The exact solving method presented has not been reported in other articles so far.Additionally,due to the difficulty of solving mathematical equations,this method is only applicable to simple boundary conditions.
文摘Two-dimensional layered aluminum-based adsorbents have been developed and successfully applied to enrich low-concentration lithium from shale gas produced water.The adsorbent,synthesized with a lithium-to-aluminum molar ratio of 0.6 in the salt solution,demonstrated exceptional performance characteristics.Its structure,featuring nano-encapsulated layers,facilitated lithium insertion,enhanced the surface area,and optimized pore size distribution for efficient adsorption.The adsorption equilibrium was reached within 60 min,closely aligning with the pseudo-second-order model.The isotherm analysis,based on the Sips model,suggested a nonhomogeneous multilayer adsorption process.Additionally,the adsorbent showed exceptional selectivity for Li^(+)over Na^(+),Ca^(2+),and Mg^(2+),ensuring effective lithium enrichment.Further desorption studies indicated that optimal conditions involved using deionized water at 333 K with a liquid-to-solid ratio of 80 mL/g.The adsorbent maintained robust performance and structural integrity through five adsorption-desorption cycles,highlighting its potential for recyclability and practical application in lithium recovery.These developments represent significant progress in harnessing lithium resources from shale gas produced water,thereby supporting advancements in clean energy technologies.
文摘The electronic packaging box with high silicon aluminum-base alloy was prepared by semi-solid thixoforming technique.The flow characteristic of the Si phase was analyzed.The microstructures of different parts of the box were observed by optical microscopy and scanning electron microscopy,and the thermophysical and mechanical properties of the box were tested.The results show that there exists the segregation phenomenon between the primary Si phase and the liquid phase during thixoforming,the liquid phase flows from the box,and the primary Si phase accumulates at the bottom of the box.The volume fraction of primary Si phase decreases gradually from the bottom to the walls.Accordingly,the thermal conductivities of bottom center and walls are 107.6 and 131.5 W/（m·K）,the coefficients of thermal expansion（CTE） are 7.9×10-6 and 10.6×10-6 K-1,respectively.The flexural strength increases slightly from 167 to 180 MPa.The microstructures and properties of the box show gradient distribution overall.
文摘The electronic packaging shell with high silicon carbide aluminum-base composites was prepared by semi-solid thixoforming technique. The flow characteristic of the Si C particulate was analyzed. The microstructures of different parts of the shell were observed by scanning electron microscopy and optical microscopy, and the thermophysical and mechanical properties of the shell were tested. The results show that there exists the segregation phenomenon between the Si C particulate and the liquid phase during thixoforming, the liquid phase flows from the shell, and the Si C particles accumulate at the bottom of the shell. The volume fraction of Si C decreases gradually from the bottom to the walls. Accordingly, the thermal conductivities of bottom center and walls are 178 and 164 W·m-1·K-1, the coefficients of thermal expansion(CTE) are 8.2×10-6 and 12.6×10-6 K-1, respectively. The flexural strength decreases slightly from 437 to 347 MPa. The microstructures and properties of the shell show gradient distribution.
基金financially supported by the Science and Technology Plan Item of Liaoning Province (No.201601174)the National Natural Science Foundation of China (No.51371121)
文摘An Al-based composite reinforced with core–shell-structured Ti/Al_3Ti was fabricated through a powder metallurgy route followed by hot extrusion and was found to exhibit promising mechanical properties. The ultimate tensile strength and elongation of the composite sintered at 620°C for 5 h and extruded at a mass ratio of 12.75:1 reached 304 MPa and 14%, respectively, and its compressive deformation reached 60%. The promising mechanical properties are due to the core–shell-structured reinforcement, which is mainly composed of Al_3Ti and Ti and is bonded strongly with the Al matrix, and to the reduced crack sensitivity of Al_3Ti. The refined grains after hot extrusion also contribute to the mechanical properties of this composite. The mechanical properties might be further improved through regulating the relative thickness of Al–Ti intermetallics and Ti metal layers by adjusting the sintering time and the subsequent extrusion process.
基金supported by the National Nature Science Foundation of China。
文摘Thermodynamic properties of Al-Ce-Mn and Al-Ce—Zn liquid systems were studied by direct equilibrium method at 700 and 800℃respectively.The results obtained include,equilibrium products,their standard Gibbs energies of formation,equilibrium constants of reactions and activity interaction coefficients between Ce and Mn or Zn in liquid aluminum.
基金Financially supported by the National Natural Science Foundation of China
文摘Thermodynamic properties of Al-Ce-Pb and Al-Ce-Sn liquid systems were studied by direct equilibrium method at 800℃. The results obtained include: equilibrium products, their standard Gibbs energies of formation, equilibrium constants of reactions and activity interaction coefficients between Ce and Pb or Sn in liquid aluminum.
基金supported by the National Natural Science Fund of China(Grant No.51878300)the Natural Science Foundation of Fujian Province of China(Grant No.2019J01052)Project of production,study and research of colleges and universities of Xiamen City(Grant No.3502Z20203044).
文摘We determined the effects of quartz sand(QS),water treatment plant sludge(WTPS),aluminum-based P-inactivation agent(Al-PIA),and lanthanum-modified bentonite(LMB)thin-layer capping on controlling phosphorus and nitrogen release from the sediment,using a static simulation experiment.The sediment in the experiment was sampled from Yundang Lagoon(Xiamen,Fujian Province,China),which is a eutrophic waterbody.The total phosphorus(TP),ammonium nitrogen(NH4+-N),and total organic carbon(TOC)levels in the overlying water were measured at regular intervals,and the changes of different P forms in WTPS,Al-PIA,and sediment of each system were analyzed before and after the test.The average TP reduction rates of LMB,Al-PIA,WTPS,and QS were 94.82,92.14,86.88,and 10.68%,respectively,when the release strength of sediment TP was 2.26–9.19 mg/(m^(2)·d)and the capping strength of the materials was 2 kg/m^(2).Thin-layer capping of LMB,WTPS,and Al-PIA could effectively control P release from the sediment(P<0.05).However,thin-layer capping of LMB,Al-PIA,and QS did not significantly reduce the release of ammonium N and organic matter(P>0.05).Based on our results,LMB,Al-PIA,and WTPS thin-layer capping promoted the migration and transformation of easily released P in sediment.The P adsorbed by WTPS and Al-PIA mainly occurred in the form of NAIP.
