Combined theoretical and experimental efforts are put forward to study the critical factors influencing deformation mode transitions in face-centered cubic materials.We revisit the empirical relationship between the s...Combined theoretical and experimental efforts are put forward to study the critical factors influencing deformation mode transitions in face-centered cubic materials.We revisit the empirical relationship between the stacking fault energy(SFE)and the prevalent deformation mechanism.With ab initio calculated SFE,we establish the critical boundaries between various deformation modes in the model Cr-Co-Ni solid solution alloys.Satisfying agreement between theoretical predictions and experimental observations are reached.Our findings shield light on applying quantum mechanical calculations in designing transformation-induced plasticity and twinning-induced plasticity mechanisms for achieving advanced mechanical properties.展开更多
High entropy alloys(HEAs)based on transition metals display rich magnetic characteristics,however attempts on their application in energy efficient technologies remain scarce.Here,we explore the magnetocaloric applica...High entropy alloys(HEAs)based on transition metals display rich magnetic characteristics,however attempts on their application in energy efficient technologies remain scarce.Here,we explore the magnetocaloric application for a series of Mn_(x)Cr_(0.3)Fe_(0.5)Co_(0.2)Ni_(0.5)Al_(0.3)(0.8<x<1.1)HEAs by integrated theoretical and experimental methods.Both theory and experiment indicate the designed HEAs have the Curie temperature close to room temperature and is tunable with Mn concentration.A non-monotonic evolution is observed for both the entropy change and the relative cooling power with changing Mn concentration.The underlying atomic mechanism is found to primarily emerge from the complex impact of Mn on magnetism.Advanced magnetocaloric properties can be achieved by tuning Mn concentration in combination with controlling structural phase stability for the designed HEAs.展开更多
In order to efficiently explore the nearly infinite composition space in multicomponent solid solution alloys for reaching higher mechanical performance,it is important to establish predictive design strategies using ...In order to efficiently explore the nearly infinite composition space in multicomponent solid solution alloys for reaching higher mechanical performance,it is important to establish predictive design strategies using computation-aided methods.Here,using ab initio calculations we systematically study the effects of magnetism and chemical composition on the generalized stacking fault energy surface(γ-surface) of Cr-Co-Ni medium entropy alloys and show that both chemistry and the coupled magnetic state strongly affect the γ-surface,consequently,the primary deformation modes.The relations among various stable and unstable stacking fault energies are revealed and discussed.The present findings are useful for studying the deformation behaviors of Cr-Co-Ni alloys and facilitate a density functional theory based design of transformation-induced plasticity and twinning-induced plasticity mechanisms in Cr-Co-Ni alloys.展开更多
In this work, five mixtures with different concentrations of banana-shaped and calamitic compounds have been prepared and subsequently studied by polarizing optical microscopy, differential scanning calorimetry, and X...In this work, five mixtures with different concentrations of banana-shaped and calamitic compounds have been prepared and subsequently studied by polarizing optical microscopy, differential scanning calorimetry, and X-ray diffraction on non-oriented samples. The phase sequences and molecular parameters of the binary systems are presented.展开更多
The application of nanotechnology in drinking water treatment and pollution cleanup is promising, as demonstrated by a number of field-based (pilot and full scale) and bench scale studies. In recent years, the use of ...The application of nanotechnology in drinking water treatment and pollution cleanup is promising, as demonstrated by a number of field-based (pilot and full scale) and bench scale studies. In recent years, the use of zero-valent iron (ZVI) for the treatment of toxic contaminants in groundwater and wastewater has received wide attention and encouraging treatment efficiencies have been documented. In this review, nanoscale iron was prepared by pulse electrodeposition of nano iron by chemical reduction of iron chloride and iron sulfate. Our research focuses on iron nanoparticles preparation and its use for aqueous Cr(VI) reduction. The Cr(VI) reduction by the nFe0 prepared by electrochemical and blasting method at neutral pH were carried. The results show that blasting-nFe0 show lower reaction than the electrochemical-nFe0. It is because the blasting-nFe0 surface contains more Fe2O3 than the other one.展开更多
The multifaceted physics of oxides is shaped by their composition and the presence of defects,which are often accompanied by the formation of polarons.The simultaneous presence of polarons and defects,and their comple...The multifaceted physics of oxides is shaped by their composition and the presence of defects,which are often accompanied by the formation of polarons.The simultaneous presence of polarons and defects,and their complex interactions,pose challenges for first-principles simulations and experimental techniques.In this study,weleveragemachine learning and a first-principles database to analyze the distribution of surface oxygen vacancies(VO)and induced small polarons on rutile TiO_(2)(110),effectively disentangling the interactions between polarons and defects.By combining neural-network supervised learning and simulated annealing,we elucidate the inhomogeneous VO distribution observed in scanning probe microscopy(SPM).展开更多
基金provided by the Major State Basic Research Development Program of China(2016YFB0701405)supported by the KTH-SJTU collaborative research and development seed grant+6 种基金the Swedish Research Councilthe Swedish Foundation for Strategic Researchthe China Scholarship Councilthe Swedish Foundation for International Cooperation in Research and Higher Educationthe Hungarian Scientific Research Fund(research project OTKA 128229)the Fundamental Research Funds for the Central Universities under grant No.N180204015partially funded by the Swedish Research Council through grant agreement no.2018–05973
文摘Combined theoretical and experimental efforts are put forward to study the critical factors influencing deformation mode transitions in face-centered cubic materials.We revisit the empirical relationship between the stacking fault energy(SFE)and the prevalent deformation mechanism.With ab initio calculated SFE,we establish the critical boundaries between various deformation modes in the model Cr-Co-Ni solid solution alloys.Satisfying agreement between theoretical predictions and experimental observations are reached.Our findings shield light on applying quantum mechanical calculations in designing transformation-induced plasticity and twinning-induced plasticity mechanisms for achieving advanced mechanical properties.
基金supported by the Swedish Research Council(2015-5335 and 2017-06474)the Swedish Foundation for Strategic Research (S14-0038 and SM16-0036)+3 种基金the Swedish Foundation for International Cooperation in Research and Higher Education(CH2015-6292)the Swedish Energy Agency,the Hungarian Scientific Research Fund (OTKA 128229)the Carl Tryggers Foundationsupport from the Swedish Energy Agency (Energimyndigheten),ST and UPP and e SSENCE
文摘High entropy alloys(HEAs)based on transition metals display rich magnetic characteristics,however attempts on their application in energy efficient technologies remain scarce.Here,we explore the magnetocaloric application for a series of Mn_(x)Cr_(0.3)Fe_(0.5)Co_(0.2)Ni_(0.5)Al_(0.3)(0.8<x<1.1)HEAs by integrated theoretical and experimental methods.Both theory and experiment indicate the designed HEAs have the Curie temperature close to room temperature and is tunable with Mn concentration.A non-monotonic evolution is observed for both the entropy change and the relative cooling power with changing Mn concentration.The underlying atomic mechanism is found to primarily emerge from the complex impact of Mn on magnetism.Advanced magnetocaloric properties can be achieved by tuning Mn concentration in combination with controlling structural phase stability for the designed HEAs.
基金financially supported by the Major State Basic Research Development Program of China(No.2016YFB0701405)supported by the KTH-SJTU collaborative research and development seed grant in 2018,the Swedish Research Council(No.2019-04971)+2 种基金the Swedish Foundation for Strategic Research,the China Scholarship Council,the Swedish Energy Agency,the Hungarian Scientific Research Fund(No.research project OTKA 128229)the Fundamental Research Funds for the Central Universities(No.N180204015)The computation resource provided by the Swedish National Infrastructure for Computing(SNIC)at the National Supercomputer Centre in Linkoping,which is partially funded by the Swedish Research Council through grant agreement no.2018-05973。
文摘In order to efficiently explore the nearly infinite composition space in multicomponent solid solution alloys for reaching higher mechanical performance,it is important to establish predictive design strategies using computation-aided methods.Here,using ab initio calculations we systematically study the effects of magnetism and chemical composition on the generalized stacking fault energy surface(γ-surface) of Cr-Co-Ni medium entropy alloys and show that both chemistry and the coupled magnetic state strongly affect the γ-surface,consequently,the primary deformation modes.The relations among various stable and unstable stacking fault energies are revealed and discussed.The present findings are useful for studying the deformation behaviors of Cr-Co-Ni alloys and facilitate a density functional theory based design of transformation-induced plasticity and twinning-induced plasticity mechanisms in Cr-Co-Ni alloys.
基金supported by the Ministry of Education and Science of the Republic of Serbia(Grant No.OI171015)the Hungarian Research Fund OTKA K81250the SASA-HAS Bilateral Scientific Exchange Project#9
文摘In this work, five mixtures with different concentrations of banana-shaped and calamitic compounds have been prepared and subsequently studied by polarizing optical microscopy, differential scanning calorimetry, and X-ray diffraction on non-oriented samples. The phase sequences and molecular parameters of the binary systems are presented.
文摘The application of nanotechnology in drinking water treatment and pollution cleanup is promising, as demonstrated by a number of field-based (pilot and full scale) and bench scale studies. In recent years, the use of zero-valent iron (ZVI) for the treatment of toxic contaminants in groundwater and wastewater has received wide attention and encouraging treatment efficiencies have been documented. In this review, nanoscale iron was prepared by pulse electrodeposition of nano iron by chemical reduction of iron chloride and iron sulfate. Our research focuses on iron nanoparticles preparation and its use for aqueous Cr(VI) reduction. The Cr(VI) reduction by the nFe0 prepared by electrochemical and blasting method at neutral pH were carried. The results show that blasting-nFe0 show lower reaction than the electrochemical-nFe0. It is because the blasting-nFe0 surface contains more Fe2O3 than the other one.
基金funded in part by the Austrian Science Fund(FWF)10.55776/F81。
文摘The multifaceted physics of oxides is shaped by their composition and the presence of defects,which are often accompanied by the formation of polarons.The simultaneous presence of polarons and defects,and their complex interactions,pose challenges for first-principles simulations and experimental techniques.In this study,weleveragemachine learning and a first-principles database to analyze the distribution of surface oxygen vacancies(VO)and induced small polarons on rutile TiO_(2)(110),effectively disentangling the interactions between polarons and defects.By combining neural-network supervised learning and simulated annealing,we elucidate the inhomogeneous VO distribution observed in scanning probe microscopy(SPM).
