Understanding the relation between spatial heterogeneity and structural rejuvenation is one of the hottest topics in the field of metallic glasses(MGs).In this work,molecular dynamics(MD)simulation is implemented to d...Understanding the relation between spatial heterogeneity and structural rejuvenation is one of the hottest topics in the field of metallic glasses(MGs).In this work,molecular dynamics(MD)simulation is implemented to discover the effects of initial spatial heterogeneity on the level of rejuvenation in the Ni_(80)P_(20)MGs.For this purpose,the samples are prepared with cooling rates of 10^(10) K/s-10^(12) K/s to make glassy alloys with different atomic configurations.Firstly,it is found that the increase in the cooling rate leads the Gaussian-type shear modulus distribution to widen,indicating the aggregations in both elastically soft and hard regions.After the primary evaluations,the elastostatic loading is also used to transform structural rejuvenation into the atomic configurations.The results indicate that the sample with intermediate structural heterogeneity prepared with 10^(11) K/s exhibits the maximum structural rejuvenation which is due to the fact that the atomic configuration in an intermediate structure contains more potential sites for generating the maximum atomic rearrangement and loosely packed regions under an external excitation.The features of atomic rearrangement and structural changes under the rejuvenation process are discussed in detail.展开更多
Further development in the field of geothermal energy require reliable reference data on the thermophysical properties of geothermal waters,namely,on the thermal conductivity and viscosity of aqueous salt solutions at...Further development in the field of geothermal energy require reliable reference data on the thermophysical properties of geothermal waters,namely,on the thermal conductivity and viscosity of aqueous salt solutions at temperatures of 293–473 K,pressures Ps=100 MPa,and concentrations of 0–25 wt.%.Given the lack of data and models,especially for the dynamic viscosity of aqueous salt solutions at a pressure of above 40 MPa,generalized formulas are presented here,by which these gaps can be filled.The article presents a generalized formula for obtaining reliable data on the thermal conductivity of water aqueous solutions of salts for Ps=100 MPa,temperatures of 293–473 K and concentrations of 0%–25%(wt.%),as well as generalized formulas for the dynamic viscosity of water up to pressures of 500 MPa and aqueous solutions of salts for Ps=100 MPa,temperatures 333–473 K,and concentration 0%–25%.The obtained values agree with the experimental data within 1.6%.展开更多
文摘Understanding the relation between spatial heterogeneity and structural rejuvenation is one of the hottest topics in the field of metallic glasses(MGs).In this work,molecular dynamics(MD)simulation is implemented to discover the effects of initial spatial heterogeneity on the level of rejuvenation in the Ni_(80)P_(20)MGs.For this purpose,the samples are prepared with cooling rates of 10^(10) K/s-10^(12) K/s to make glassy alloys with different atomic configurations.Firstly,it is found that the increase in the cooling rate leads the Gaussian-type shear modulus distribution to widen,indicating the aggregations in both elastically soft and hard regions.After the primary evaluations,the elastostatic loading is also used to transform structural rejuvenation into the atomic configurations.The results indicate that the sample with intermediate structural heterogeneity prepared with 10^(11) K/s exhibits the maximum structural rejuvenation which is due to the fact that the atomic configuration in an intermediate structure contains more potential sites for generating the maximum atomic rearrangement and loosely packed regions under an external excitation.The features of atomic rearrangement and structural changes under the rejuvenation process are discussed in detail.
文摘Further development in the field of geothermal energy require reliable reference data on the thermophysical properties of geothermal waters,namely,on the thermal conductivity and viscosity of aqueous salt solutions at temperatures of 293–473 K,pressures Ps=100 MPa,and concentrations of 0–25 wt.%.Given the lack of data and models,especially for the dynamic viscosity of aqueous salt solutions at a pressure of above 40 MPa,generalized formulas are presented here,by which these gaps can be filled.The article presents a generalized formula for obtaining reliable data on the thermal conductivity of water aqueous solutions of salts for Ps=100 MPa,temperatures of 293–473 K and concentrations of 0%–25%(wt.%),as well as generalized formulas for the dynamic viscosity of water up to pressures of 500 MPa and aqueous solutions of salts for Ps=100 MPa,temperatures 333–473 K,and concentration 0%–25%.The obtained values agree with the experimental data within 1.6%.
