Mg-based hydrides are too stable and the kinetics of hydrogen absorption and desorption is not satisfactory.An efficient way to improve these shortcomings is to employ reactive ball milling to synthesize the nanocompo...Mg-based hydrides are too stable and the kinetics of hydrogen absorption and desorption is not satisfactory.An efficient way to improve these shortcomings is to employ reactive ball milling to synthesize the nanocomposite materials of Mg and additives.In this experiment,TiF_(3)was selected as an additive,and the mechanical milling method was employed to prepare the experimental alloys.The alloys used in this experiment were the as-cast Ce_(5)Mg_(85)Ni_(10),as-milled Ce_(5)Mg_(85)Ni_(10)and Ce_(5)Mg_(85)Ni_(10)+3 wt.%TiF3.The phase transformation,structural evolution,isothermal and non-isothermal hydrogenation and dehydrogenation performances of the alloys were inspected by XRD,SEM,TEM,Sievert apparatus,DSC and TGA.It revealed that nanocrystalline appeared in the as-milled samples.Compared with the as-cast alloy,ball milling made the particle dimension and grain size decrease dramatically and the defect density increase significantly.The addition of TiF_(3)made the surface of ball milling alloy particles markedly coarser and more irregular.Ball milling and adding TiF_(3)distinctly improved the activation and kinetics of the alloys.Moreover,ball milling along with TiF_(3)can decrease the onset dehydrogenation temperature of Mg-based hydrides and slightly ameliorate their thermodynamics.展开更多
Achieving the strength-ductility synergy in Mg alloys is a gigantic challenge,especially in rare-earth-free Mg alloys.In this study,a new Mg-Sn-Zn-Zr alloy with high ultimate tensile strength(~284-326 MPa)without sacr...Achieving the strength-ductility synergy in Mg alloys is a gigantic challenge,especially in rare-earth-free Mg alloys.In this study,a new Mg-Sn-Zn-Zr alloy with high ultimate tensile strength(~284-326 MPa)without sacrificing elongation-to-failure(~22.1-27.6%)was developed by utilizing casting,pre-treatment and hot extrusion.Strong random rather than basal texture is observed both in as-cast and pre-treatment samples.Subsequently,the strong texture is effectively weakened via hot extrusion whilst remaining random.More importantly,after hot extrusion,the grain sizes of as-cast and pre-treatment samples were significantly refined down to about 10μm.Examination of as-extruded microstructures of the alloy reveals that the grain refinement is highly associated with the particle stimulated nucleation(PSN)and continuous/discontinuous dynamic recrystallization(C/DDRX)mechanisms.Moreover,the results suggest that the combination of pre-treatment and hot extrusion not only promotes multiplication of geometrically-necessary dislocations(GNDs)but enhances dynamic precipitation,which boosts the formation of fine and homogenous precipitates.Based on the results of X-ray diffraction(XRD),transmission electron microscope(TEM)and selected area electron diffraction(SAED),the precipitates are Mg_(2)Sn phases.Furthermore,the main orientation relationship identified by high resolution TEM(HRTEM)between Mg_(2)Sn phases andα-Mg matrix could be described as(111)Mg_(2)Snor(220)Mg_(2)Sn∥(0001)Mgwith a coherent interface.The refined grains size,ultra-fine precipitates and high density of GNDs would substantially contribute to the enhancement of the strength and the corresponding contributions are calculated to be~183-185 MPa,~30.9-38 MPa and~14.2-31.7 MPa,respectively.Besides,texture weakening or randomizing,grain refinement and coherent interfaces are mainly responsible for the high ductility.The current study can provide beneficial insights into the development of high-performance rare-earth-free Mg alloys with favorable microstructure via a combination of casting,pre-treatment and hot extrusion processing.展开更多
Photoactive complexes of nonprecious transition metals,mainly including those in the first-row and partially the second-row of the Periodic table of elements,have received increasing attention in view of their low cos...Photoactive complexes of nonprecious transition metals,mainly including those in the first-row and partially the second-row of the Periodic table of elements,have received increasing attention in view of their low cost and long-term sustainability.They are recognized as promising alternatives to noble transition metal complex congeners that have been extensively studied in optoelectronic devices,artificial photosynthesis,photocatalysis,biodiagnostics,and therapeutics,etc.This review is devoted to a comprehensive summary on the classical and recent advances on photoactive nonprecious transition metal complexes,including photoactive Zr,V,Cr,Mo,and W complexes,Mn complexes and hybrids,Fe,Co,Ni,and Cu complexes,and Zn and Cd complexes and hybrids.A particular focus is given on the molecular design,modulation of photophysical and photochemical properties,and applications of the representative and lately-developed nonprecious metal complexes.In addition,a perspective on the future development in this field is provided at the end of this review.展开更多
Covalent organic frameworks(COFs)are one class of porous materials with permanent porosity and regular channels,and have a covalent bond structure.Due to their interesting characteristics,COFs have exhibited diverse p...Covalent organic frameworks(COFs)are one class of porous materials with permanent porosity and regular channels,and have a covalent bond structure.Due to their interesting characteristics,COFs have exhibited diverse potential applications in many felds.However,some applications require the frameworks to possess high structural stability,excellent crystallinity,and suitable pore size.COFs based onβ-ketoenamine and imines are prepared through the irreversible enol-to-keto tautomerization.These materials have high crystallinity and exhibit high stability in boiling water,with strong resistance to acids and bases,resulting in various possible applications.In this review,we frst summarize the preparation methods for COFs based onβ-ketoenamine,in the form of powders,flms and foams.Then,the efects of diferent synthetic methods on the crystallinity and pore structure of COFs based onβ-ketoenamine are analyzed and compared.The relationship between structures and diferent applications including fuorescence sensors,energy storage,photocatalysis,electrocatalysis,batteries and proton conduction are carefully summarized.Finally,the potential applications,large-scale industrial preparation and challenges in the future are presented.展开更多
Porcine epidemic diarrhea virus(PEDV),an enteropathogenic coronavirus,has catastrophic impacts on the global pig industry.However,there remain no effective drugs against PEDV infection.In this study,we utilized a reco...Porcine epidemic diarrhea virus(PEDV),an enteropathogenic coronavirus,has catastrophic impacts on the global pig industry.However,there remain no effective drugs against PEDV infection.In this study,we utilized a recombinant PEDV expressing renilla luciferase(PEDV-Rluc)to screen potential anti-PEDV agents from an FDAapproved drug library in Vero cells.Four compounds were identified that significantly decreased luciferase activity of PEDV-Rluc.Among them,niclosamide was further characterized because it exhibited the most potent antiviral activity with the highest selectivity index.It can efficiently inhibit viral RNA synthesis,protein expression and viral progeny production of classical and variant PEDV strains in a dose-dependent manner.Time of addition assay showed that niclosamide exhibited potent anti-PEDV activity when added simultaneously with or after virus infection.Furthermore,niclosamide significantly inhibited the entry stage of PEDV infection by affecting viral internalization rather than viral attachment to cells.In addition,a combination with other small molecule inhibitors of endosomal acidification enhanced the anti-PEDV effect of niclosamide in vitro.Taken together,these findings suggested that niclosamide is a novel antiviral agent that might provide a basis for the development of novel drug therapies against PEDV and other related pathogenic coronavirus infections.展开更多
The La-Mg-Ni-Co-Al-based AB2-type La0.8-xCe0.2YxMgNi3.4Co0.4Al0.1 （x = 0, 0.05, 0.1, 0.15, 0.2） alloys were prepared by melt spinning. The effects of Y content on the structures and electrochemical hydrogen storage ...The La-Mg-Ni-Co-Al-based AB2-type La0.8-xCe0.2YxMgNi3.4Co0.4Al0.1 （x = 0, 0.05, 0.1, 0.15, 0.2） alloys were prepared by melt spinning. The effects of Y content on the structures and electrochemical hydrogen storage characters were thoroughly studied. The structures of the experimental samples were analyzed by X-ray diffraction （XRD） and scanning electron microscopy （SEM）. It is shown that there are a main phase LaMgNi4 and a second phase LaNi5 in the experimental samples. The variation of Y content incurs obvious changes of the phase abundance without changing phase composition. Namely, with the increase of Y content, the LaMgNi4 phase increases and LaNi5 phase decreases. Furthermore, melt spinning and the replacement of Y for La also lead to the grains refinement of the alloy. The electrochemical tests display that the as-spun alloys possess excellent activation properties, and obtain the maximums of discharge capacity at the first cycling. The replacement of Y for La can visibly facilitate the discharge potential characteristics, however,diminish the discharge capacity. The electrochemical kinetics, involving in the high rate discharge ability （HRD）, hydrogen diffusion coefficient （D）, limiting current density （IL） and charge transfer rate, increases firstly and then decreases with the increase of Y content. The cyclic stability is greatly improved by melt spinning and the replacement of Y for La, which is derived from the improvement of the anti-corrosion, oxidation-resistance and the anti-pulverization abilities.展开更多
For purpose of promoting the hydrogen absorption and desorption thermodynamics and kinetics properties of Mg-Ni-based alloys, partially substituting Y and Cu for Mg and Ni respectively and melt spinning technique were...For purpose of promoting the hydrogen absorption and desorption thermodynamics and kinetics properties of Mg-Ni-based alloys, partially substituting Y and Cu for Mg and Ni respectively and melt spinning technique were applied for getting Mg25-xYxNi9 Cu(χ = 0-7) alloys. Their microstructures and phases were characterized with the help of X-ray diffraction and transmission electron microscopy. Their hydrogen absorbing and desorbing properties were tested by a Sievert apparatus, DSC, and TGA, which were connected with a H2 detector. In order to estimate the dehydrogenation activation energy of alloy hydride, both Arrhenius and Kissinger methods were applied for calculation. It is found that their hydriding kinetics notably declines, however, their hydrogen desorption kinetics conspicuously improves, with spinning rate and Y content increasing. Their hydrogen desorption activation energy markedly decreases under the same constraint, and it is found that melt spinning and Y substituting Mg improve the real driving force for dehydrogenation. As for the tendency of hydrogen absorption capacity,it presents an elevation firstly and soon after a decline with the rising of spinning rate, however, it always lowers with Y content growing. With Y content and spinning rate increasing, their thermodynamic parameters(△H and △S absolute values) visibly decrease, and the starting hydrogen desorption temperatures of alloy hydrides obviously lower.展开更多
Ploidy manipulation,such as triploidy,in farmed oysters has been used as a tool to enhance oyster quality throughout all seasons because triploid oysters allocate less energy to gametogenesis,and therefore are deemed ...Ploidy manipulation,such as triploidy,in farmed oysters has been used as a tool to enhance oyster quality throughout all seasons because triploid oysters allocate less energy to gametogenesis,and therefore are deemed better performers than fertile diploids.Nevertheless,scientific reports describing no differences between ploidies and,in certain conditions,disadvantages of triploids are not uncommon.As the use of triploid oyster seed increases culture cost for growers,consistency in performance of triploids is considered to be an important goal.Thus,research to assess how ploidy affects physiological processes underlying oyster performance is fundamental for the aquaculture industry.This work was undertaken to assess if ploidy-based differences in performance in the two most commonly cultivated commercial species of oyster in the United States,Crassostrea virginica and Crassostrea gigas,are associated with filtration,feeding,and metabolism.To test this hypothesis,biodeposition measurements were made with oysters exposed to ambient water conditions at locations and seasons providing a variety of environmental conditions.Oysters did not show differences in filtration and feeding associated with ploidy,but physiological feeding variables fluctuated with environmental characteristics associated with spatial and seasonal differences.A preliminarily test of the hypothesis that differences in energy metabolism may account for differences in performance among ploidy levels indicates that basal metabolic rates of diploid,triploid,and tetraploid Eastern oysters are not different.展开更多
Developing high-ductility magnesium(Mg)alloys has become an imminent issue for their wide appli-cation.In this work,a new Mg-Sn-Zn-Zr alloy with ultra-high ductility(elongation,El.over 40%)and high ultimate tensile st...Developing high-ductility magnesium(Mg)alloys has become an imminent issue for their wide appli-cation.In this work,a new Mg-Sn-Zn-Zr alloy with ultra-high ductility(elongation,El.over 40%)and high ultimate tensile strength(UTS,~309-354 MPa)was prepared by a novel differential thermal equal-channel angular pressing(DT-ECAP).Heterogeneous structures,including bimodal grain structures and in-homogeneous distribution of second phases composed of banded structure and particle free zone(PFZ),were induced by DT-ECAP process.Based on the results of electron backscatter diffraction(EBSD),trans-mission electron microscopy(TEM),high-resolution TEM(HRTEM),and selected area electron diffraction(SAED),the bimodal grain structure originated from incomplete dynamic recrystallization(DRX)domi-nated by Zener pinning,strain-induced grain boundary migration(SIBM)and the limitation of polycrys-tallization due to lower dislocation density.Meanwhile,the bimodal distribution of second phases was highly associated with the defect density and initial structure.More importantly,the enhanced strength of DT-ECAPed alloys can be primarily attributed to hetero-deformation induced(HDI)strengthening,grain boundary strengthening,and precipitation strengthening.Moreover,HDI hardening,texture weakening or randomizing activation of non-basal slip,high density of dislocations in sub-structures,and twining in-duced superior work-hardening effect,which was highly responsible for the ultra-high ductility in sixth pass(6P)alloy.The current work provides a novel DT-ECAP process for inducing heterogeneous structure and offers beneficial insight into the development of ultra-high ductility and high strength for rare-earth-free Mg alloys via a combination of HDI strengthening and hardening and other vital mechanisms.展开更多
The gender difference of MDD inepidemiology and clinical symptomatology Major depressive disorder(MDD)is a common and serious mental disorder(Li et al.,2022;Malhi&Mann,2018).Male and female patients with MDD have ...The gender difference of MDD inepidemiology and clinical symptomatology Major depressive disorder(MDD)is a common and serious mental disorder(Li et al.,2022;Malhi&Mann,2018).Male and female patients with MDD have shown some differences in the epidemiology and clinical symptomatology.展开更多
基金the National Natural Science Foundation of China(Nos.51871125,51761032,52001005 and 51731002)Major Science and Technology Innovation Projects in Shandong Province(No.2019JZZY010320)for financial support of the work.
文摘Mg-based hydrides are too stable and the kinetics of hydrogen absorption and desorption is not satisfactory.An efficient way to improve these shortcomings is to employ reactive ball milling to synthesize the nanocomposite materials of Mg and additives.In this experiment,TiF_(3)was selected as an additive,and the mechanical milling method was employed to prepare the experimental alloys.The alloys used in this experiment were the as-cast Ce_(5)Mg_(85)Ni_(10),as-milled Ce_(5)Mg_(85)Ni_(10)and Ce_(5)Mg_(85)Ni_(10)+3 wt.%TiF3.The phase transformation,structural evolution,isothermal and non-isothermal hydrogenation and dehydrogenation performances of the alloys were inspected by XRD,SEM,TEM,Sievert apparatus,DSC and TGA.It revealed that nanocrystalline appeared in the as-milled samples.Compared with the as-cast alloy,ball milling made the particle dimension and grain size decrease dramatically and the defect density increase significantly.The addition of TiF_(3)made the surface of ball milling alloy particles markedly coarser and more irregular.Ball milling and adding TiF_(3)distinctly improved the activation and kinetics of the alloys.Moreover,ball milling along with TiF_(3)can decrease the onset dehydrogenation temperature of Mg-based hydrides and slightly ameliorate their thermodynamics.
基金National Natural Science Foundation of China(No.12162023)The Key Talent Projects of Gansu Province,Gansu Basic Research Innovation Group Project(No.23JRRA757)Incubation Program of Excellent Doctoral Dissertation-Lanzhou University of Technology。
文摘Achieving the strength-ductility synergy in Mg alloys is a gigantic challenge,especially in rare-earth-free Mg alloys.In this study,a new Mg-Sn-Zn-Zr alloy with high ultimate tensile strength(~284-326 MPa)without sacrificing elongation-to-failure(~22.1-27.6%)was developed by utilizing casting,pre-treatment and hot extrusion.Strong random rather than basal texture is observed both in as-cast and pre-treatment samples.Subsequently,the strong texture is effectively weakened via hot extrusion whilst remaining random.More importantly,after hot extrusion,the grain sizes of as-cast and pre-treatment samples were significantly refined down to about 10μm.Examination of as-extruded microstructures of the alloy reveals that the grain refinement is highly associated with the particle stimulated nucleation(PSN)and continuous/discontinuous dynamic recrystallization(C/DDRX)mechanisms.Moreover,the results suggest that the combination of pre-treatment and hot extrusion not only promotes multiplication of geometrically-necessary dislocations(GNDs)but enhances dynamic precipitation,which boosts the formation of fine and homogenous precipitates.Based on the results of X-ray diffraction(XRD),transmission electron microscope(TEM)and selected area electron diffraction(SAED),the precipitates are Mg_(2)Sn phases.Furthermore,the main orientation relationship identified by high resolution TEM(HRTEM)between Mg_(2)Sn phases andα-Mg matrix could be described as(111)Mg_(2)Snor(220)Mg_(2)Sn∥(0001)Mgwith a coherent interface.The refined grains size,ultra-fine precipitates and high density of GNDs would substantially contribute to the enhancement of the strength and the corresponding contributions are calculated to be~183-185 MPa,~30.9-38 MPa and~14.2-31.7 MPa,respectively.Besides,texture weakening or randomizing,grain refinement and coherent interfaces are mainly responsible for the high ductility.The current study can provide beneficial insights into the development of high-performance rare-earth-free Mg alloys with favorable microstructure via a combination of casting,pre-treatment and hot extrusion processing.
基金supported by the National Natural Science Foundation of China(21925112,22175181,22371063,22175191,22075027,and 22475002)。
文摘Photoactive complexes of nonprecious transition metals,mainly including those in the first-row and partially the second-row of the Periodic table of elements,have received increasing attention in view of their low cost and long-term sustainability.They are recognized as promising alternatives to noble transition metal complex congeners that have been extensively studied in optoelectronic devices,artificial photosynthesis,photocatalysis,biodiagnostics,and therapeutics,etc.This review is devoted to a comprehensive summary on the classical and recent advances on photoactive nonprecious transition metal complexes,including photoactive Zr,V,Cr,Mo,and W complexes,Mn complexes and hybrids,Fe,Co,Ni,and Cu complexes,and Zn and Cd complexes and hybrids.A particular focus is given on the molecular design,modulation of photophysical and photochemical properties,and applications of the representative and lately-developed nonprecious metal complexes.In addition,a perspective on the future development in this field is provided at the end of this review.
基金supported by the Open Fund of Beijing National Laboratory for Molecular Sciences(No.BNLMS201842)The Open Fund of the State Key Laboratory of Advanced Technology for Materials Synthesis and Processing(Wuhan University of Technology)(No.2020-KF-17)+1 种基金Postgraduate Innovation Foundation from Wuhan Institute of Technologysupport from starting funds from City University of Hongkong and 111 Project(No.D20015).
文摘Covalent organic frameworks(COFs)are one class of porous materials with permanent porosity and regular channels,and have a covalent bond structure.Due to their interesting characteristics,COFs have exhibited diverse potential applications in many felds.However,some applications require the frameworks to possess high structural stability,excellent crystallinity,and suitable pore size.COFs based onβ-ketoenamine and imines are prepared through the irreversible enol-to-keto tautomerization.These materials have high crystallinity and exhibit high stability in boiling water,with strong resistance to acids and bases,resulting in various possible applications.In this review,we frst summarize the preparation methods for COFs based onβ-ketoenamine,in the form of powders,flms and foams.Then,the efects of diferent synthetic methods on the crystallinity and pore structure of COFs based onβ-ketoenamine are analyzed and compared.The relationship between structures and diferent applications including fuorescence sensors,energy storage,photocatalysis,electrocatalysis,batteries and proton conduction are carefully summarized.Finally,the potential applications,large-scale industrial preparation and challenges in the future are presented.
基金supported by the National Natural Science Foundation of China(Grant No.31602033 and 32172839)the China Scholarship Council under grant 201908410129.
文摘Porcine epidemic diarrhea virus(PEDV),an enteropathogenic coronavirus,has catastrophic impacts on the global pig industry.However,there remain no effective drugs against PEDV infection.In this study,we utilized a recombinant PEDV expressing renilla luciferase(PEDV-Rluc)to screen potential anti-PEDV agents from an FDAapproved drug library in Vero cells.Four compounds were identified that significantly decreased luciferase activity of PEDV-Rluc.Among them,niclosamide was further characterized because it exhibited the most potent antiviral activity with the highest selectivity index.It can efficiently inhibit viral RNA synthesis,protein expression and viral progeny production of classical and variant PEDV strains in a dose-dependent manner.Time of addition assay showed that niclosamide exhibited potent anti-PEDV activity when added simultaneously with or after virus infection.Furthermore,niclosamide significantly inhibited the entry stage of PEDV infection by affecting viral internalization rather than viral attachment to cells.In addition,a combination with other small molecule inhibitors of endosomal acidification enhanced the anti-PEDV effect of niclosamide in vitro.Taken together,these findings suggested that niclosamide is a novel antiviral agent that might provide a basis for the development of novel drug therapies against PEDV and other related pathogenic coronavirus infections.
基金financially supported by the National Natural Science Foundations of China (Nos. 51371094 and 51471054)the Natural Science Foundation of Inner Mongolia, China (No. 2015MS0558)
文摘The La-Mg-Ni-Co-Al-based AB2-type La0.8-xCe0.2YxMgNi3.4Co0.4Al0.1 （x = 0, 0.05, 0.1, 0.15, 0.2） alloys were prepared by melt spinning. The effects of Y content on the structures and electrochemical hydrogen storage characters were thoroughly studied. The structures of the experimental samples were analyzed by X-ray diffraction （XRD） and scanning electron microscopy （SEM）. It is shown that there are a main phase LaMgNi4 and a second phase LaNi5 in the experimental samples. The variation of Y content incurs obvious changes of the phase abundance without changing phase composition. Namely, with the increase of Y content, the LaMgNi4 phase increases and LaNi5 phase decreases. Furthermore, melt spinning and the replacement of Y for La also lead to the grains refinement of the alloy. The electrochemical tests display that the as-spun alloys possess excellent activation properties, and obtain the maximums of discharge capacity at the first cycling. The replacement of Y for La can visibly facilitate the discharge potential characteristics, however,diminish the discharge capacity. The electrochemical kinetics, involving in the high rate discharge ability （HRD）, hydrogen diffusion coefficient （D）, limiting current density （IL） and charge transfer rate, increases firstly and then decreases with the increase of Y content. The cyclic stability is greatly improved by melt spinning and the replacement of Y for La, which is derived from the improvement of the anti-corrosion, oxidation-resistance and the anti-pulverization abilities.
基金Project supported by the National Natural Science Foundation of China(51761032,51471054,51871125)
文摘For purpose of promoting the hydrogen absorption and desorption thermodynamics and kinetics properties of Mg-Ni-based alloys, partially substituting Y and Cu for Mg and Ni respectively and melt spinning technique were applied for getting Mg25-xYxNi9 Cu(χ = 0-7) alloys. Their microstructures and phases were characterized with the help of X-ray diffraction and transmission electron microscopy. Their hydrogen absorbing and desorbing properties were tested by a Sievert apparatus, DSC, and TGA, which were connected with a H2 detector. In order to estimate the dehydrogenation activation energy of alloy hydride, both Arrhenius and Kissinger methods were applied for calculation. It is found that their hydriding kinetics notably declines, however, their hydrogen desorption kinetics conspicuously improves, with spinning rate and Y content increasing. Their hydrogen desorption activation energy markedly decreases under the same constraint, and it is found that melt spinning and Y substituting Mg improve the real driving force for dehydrogenation. As for the tendency of hydrogen absorption capacity,it presents an elevation firstly and soon after a decline with the rising of spinning rate, however, it always lowers with Y content growing. With Y content and spinning rate increasing, their thermodynamic parameters(△H and △S absolute values) visibly decrease, and the starting hydrogen desorption temperatures of alloy hydrides obviously lower.
基金This work was funded by NOAA Internal Competitive Aquaculture Grant,by the South Korean National Institute of Fisheries Science(R2018012)a JPA project between the U.S.and South Korea,and by a fellowship award from the United States National Academy of Sciences.
文摘Ploidy manipulation,such as triploidy,in farmed oysters has been used as a tool to enhance oyster quality throughout all seasons because triploid oysters allocate less energy to gametogenesis,and therefore are deemed better performers than fertile diploids.Nevertheless,scientific reports describing no differences between ploidies and,in certain conditions,disadvantages of triploids are not uncommon.As the use of triploid oyster seed increases culture cost for growers,consistency in performance of triploids is considered to be an important goal.Thus,research to assess how ploidy affects physiological processes underlying oyster performance is fundamental for the aquaculture industry.This work was undertaken to assess if ploidy-based differences in performance in the two most commonly cultivated commercial species of oyster in the United States,Crassostrea virginica and Crassostrea gigas,are associated with filtration,feeding,and metabolism.To test this hypothesis,biodeposition measurements were made with oysters exposed to ambient water conditions at locations and seasons providing a variety of environmental conditions.Oysters did not show differences in filtration and feeding associated with ploidy,but physiological feeding variables fluctuated with environmental characteristics associated with spatial and seasonal differences.A preliminarily test of the hypothesis that differences in energy metabolism may account for differences in performance among ploidy levels indicates that basal metabolic rates of diploid,triploid,and tetraploid Eastern oysters are not different.
基金supported by the National Natu-ral Science Foundation of China(No.12162023)The Key Talent Projects of Gansu Province,Gansu Basic Research Innovation Group Project(No.23JRRA757)Incubation Program of Excellent Doc-toral Dissertation-Lanzhou University of Technology.
文摘Developing high-ductility magnesium(Mg)alloys has become an imminent issue for their wide appli-cation.In this work,a new Mg-Sn-Zn-Zr alloy with ultra-high ductility(elongation,El.over 40%)and high ultimate tensile strength(UTS,~309-354 MPa)was prepared by a novel differential thermal equal-channel angular pressing(DT-ECAP).Heterogeneous structures,including bimodal grain structures and in-homogeneous distribution of second phases composed of banded structure and particle free zone(PFZ),were induced by DT-ECAP process.Based on the results of electron backscatter diffraction(EBSD),trans-mission electron microscopy(TEM),high-resolution TEM(HRTEM),and selected area electron diffraction(SAED),the bimodal grain structure originated from incomplete dynamic recrystallization(DRX)domi-nated by Zener pinning,strain-induced grain boundary migration(SIBM)and the limitation of polycrys-tallization due to lower dislocation density.Meanwhile,the bimodal distribution of second phases was highly associated with the defect density and initial structure.More importantly,the enhanced strength of DT-ECAPed alloys can be primarily attributed to hetero-deformation induced(HDI)strengthening,grain boundary strengthening,and precipitation strengthening.Moreover,HDI hardening,texture weakening or randomizing activation of non-basal slip,high density of dislocations in sub-structures,and twining in-duced superior work-hardening effect,which was highly responsible for the ultra-high ductility in sixth pass(6P)alloy.The current work provides a novel DT-ECAP process for inducing heterogeneous structure and offers beneficial insight into the development of ultra-high ductility and high strength for rare-earth-free Mg alloys via a combination of HDI strengthening and hardening and other vital mechanisms.
基金supported by the national natural science foundation of China(NSFC31971018)Sichuan distinguished young scholar fund(2023NSFSC1938).
文摘The gender difference of MDD inepidemiology and clinical symptomatology Major depressive disorder(MDD)is a common and serious mental disorder(Li et al.,2022;Malhi&Mann,2018).Male and female patients with MDD have shown some differences in the epidemiology and clinical symptomatology.
