To investigate groundwater flow and solute transport characteristics of the karst trough zone in China,tracer experiments were conducted at two adjacent typical karst groundwater flow systems(Yuquandong(YQD)and Migong...To investigate groundwater flow and solute transport characteristics of the karst trough zone in China,tracer experiments were conducted at two adjacent typical karst groundwater flow systems(Yuquandong(YQD)and Migongquan(MGQ))in Sixi valley,western Hubei,China.Highresolution continuous monitoring was utilized to obtain breakthrough curves(BTCs),which were then analyzed using the multi-dispersion model(MDM)and the two-region nonequilibrium model(2RNE)with basic parameters calculated by CXTFIT and QTRACER2.Results showed that:(1)YQD flow system had a complex infiltration matrix with overland flow,conduit flow and fracture flow,while the MGQ flow system was dominated by conduit flow with fast flow transport velocity,but also small amount of fracture flow there;(2)They were well fitted based on the MDM(R^2=0.928)and 2RNE(R^2=0.947)models,indicating that they had strong adaptability in the karst trough zone;(3)conceptual models for YQD and MGQ groundwater systems were generalized.In YQD system,the solute was transported via overland flow during intense rainfall,while some infiltrated down into fissures and conduits.In MGQ system,most were directly transported to spring outlet in the fissureconduit network.展开更多
A microscopic understanding of the complex solute-defect interaction is pivotal for optimizing the alloy’s macroscopic mechanical properties.Simulating solute segregation in a plastically deformed crystalline system ...A microscopic understanding of the complex solute-defect interaction is pivotal for optimizing the alloy’s macroscopic mechanical properties.Simulating solute segregation in a plastically deformed crystalline system at atomic resolution remains challenging.The objective is to efficiently model and predict a phys-ically informed segregated solute distribution rather than simulating a series of diffusion kinetics.To ad-dress this objective,we coupled molecular dynamics(MD)and Monte Carlo(MC)methods using a novel method based on virtual atoms technique.We applied our MD-MC coupling approach to model off-lattice carbon(C)solute segregation in nanoindented Fe-C samples containing complex dislocation networks.Our coupling framework yielded the final configuration through efficient parallelization and localized en-ergy computations,showing C Cottrell atmospheres near dislocations.Different initial C concentrations resulted in a consistent trend of C atoms migrating from less crystalline distortion to high crystalline distortion regions.Besides unraveling the strong spatial correlation between local C concentration and defect regions,our results revealed two crucial aspects of solute segregation preferences:(1)defect ener-getics hierarchy and(2)tensile strain fields near dislocations.The proposed approach is generic and can be applied to other material systems as well.展开更多
With the evolution of nickel-based single crystal superalloys,there is an increase in heavy elements such as Re and Ru.This has made solutal convection more pronounced during the directional solidification process,lea...With the evolution of nickel-based single crystal superalloys,there is an increase in heavy elements such as Re and Ru.This has made solutal convection more pronounced during the directional solidification process,leading to solute redistribution and increasing the risk of casting defects such as low-angle grain boundaries.To avoid casting defects,downward directional solidification(DWS)method is adopted to eliminate solutal convection and change solute redistribution.However,there is currently no in-situ characterization or quantitative simulation studying the solute redistribution during DWS and upward directional solidification(UWS)processes.A multicomponent phase field simulation coupled with lattice Boltzmann method was employed to quantitatively investigate changes in dendrite morphology,solutal convection and deviation of dendrite tips from the perspective of solute redistribution during UWS and DWS processes.The simulation of microstructure agrees well with the experimental results.The mechanism that explains how solutal convection affects side branching behavior is depicted.A novel approach is introduced to characterize dendrite deviation,elucidating the reasons why defects are prone to occur under the influence of natural convection and solute redistribution.展开更多
Second period elements(B,C,N,and O)usually appear at the grain boundary(GB)and strongly affect the mechanical performance in austenitic stainless steels.Therefore,it is significant to investigate the effect of solute ...Second period elements(B,C,N,and O)usually appear at the grain boundary(GB)and strongly affect the mechanical performance in austenitic stainless steels.Therefore,it is significant to investigate the effect of solute elements(B,C,N,and O)on the GB.The first-principles calculation based on the density function theory was applied to explore the effect of B,C,N,and O onγ-FeΣ5(210)[001]GB.The GB energy,the segregation energy,the Voronoi volume,and the theoretical tensile test were calculated to investigate the segregation behavior and the strengthening effect.The structural change and electronic evolution were also investigated by bond change,charge density distribution,and density of states.The results show that B is favored to segregate at the capped trigonal prism(CTP)position with a large void and has a strengthening effect on the GB strength,while O and N are preferred to locate at the octahedral(OCT)site and have an embrittling effect on GB cohesion.C can segregate at both the CTP site and the OCT location with little energy difference.As C segregates at the OCT site,it is beneficial for GB strength.However,it is detrimental at the CTP position.It can be seen that the influence of solutes is closely related to the element type and segregated position.展开更多
A novel core-shell structured Al_(8)Mn_(4)Y-Al_(2)Ca phase and controllable solute-segregation are elaborately designed in dilute Mg-0.6Al-0.5Mn-0.1Ca-0.1Y alloy(wt.%),via incomplete peritectic transformation during t...A novel core-shell structured Al_(8)Mn_(4)Y-Al_(2)Ca phase and controllable solute-segregation are elaborately designed in dilute Mg-0.6Al-0.5Mn-0.1Ca-0.1Y alloy(wt.%),via incomplete peritectic transformation during twin-roll casting.When soaked in 3.5 wt.%NaCl solution,Al_(2)Ca shell with a low electrochemical potential prevents direct contact of noble Al_(8)Mn_(4)Y with Mg matrix,mitigating the micro-galvanic corrosion and meanwhile accelerating the formation of uniform corrosion film.Thereafter,solute(Al,Ca)-segregation motivates the formation of heterogeneous multilayered corrosion product films,enhancing corrosion resistance and even achieving self-healing upon long-term corrosion.Notably,the dilute Mg alloy exhibits a corrosion rate as low as 0.22±0.05 mm·y^(−1).展开更多
Interface segregation of solute atoms has a profound effect on properties of engineering alloys.In this study,we report a novel strategy for breaking the strength-ductility dilemma of Mg alloy via solute segregation.T...Interface segregation of solute atoms has a profound effect on properties of engineering alloys.In this study,we report a novel strategy for breaking the strength-ductility dilemma of Mg alloy via solute segregation.The hot extruded Mg-1.8Gd-0.3Zr(wt.%)alloy sheet was subjected to three different passes of rolling,and then heat-treated at 200℃.The high-angle annular dark-field scanning transmission electron microscopy(HAADF-STEM)reveals a remarkable segregation of solute Gd atoms along high and low-angel grain boundaries(GBs).Under almost precipitation-free conditions,the strength and ductility of rolled alloy sheets are simultaneously improved after annealing.Especially for the annealed 3-passes-rolled specimen,the yield strength,ultimate tensile strength,and elongation are simultaneously increased by 11.2%,7.3%,and 18%,respectively.The solute segregation endows the rolled plate with excellent grain size stability and provides a prominent extra solute cluster strengthening,which completely resists the other softening effects,including dislocation annihilation and grain coarsening during the heating.Meanwhile,the directional migration of Gd atoms and the annihilation of dislocations provide a“clear”space within the grain,which is beneficial for the moving and accumulating of subsequent dislocations.This work sheds light on the solute partitioning behavior and realizes a good application of GB segregation in improving the comprehensive mechanical properties of Mg alloys.展开更多
In this study,a novel strategy for breaking the strength-ductility dilemma of Mg-1.5Zn-0.6Gd(wt%)alloy via solute segregation was reported.The hot extruded alloy sheet was subjected to rolling deformation,and then hea...In this study,a novel strategy for breaking the strength-ductility dilemma of Mg-1.5Zn-0.6Gd(wt%)alloy via solute segregation was reported.The hot extruded alloy sheet was subjected to rolling deformation,and then heat-treated at 200℃.The high-angle annular dark-field scanning transmission electron microscopy(HAADF-STEM)reveals a remarkable segregation of solute Zn atoms along both high and lowangle grain boundaries(GBs).As compared with as-rolled plate,the yield strength,ultimate tensile strength,and the elongation of annealed sample is increased by 15.6%,14%,and 8.4%,respectively,acquiring an obvious strength-ductility synergy effect.The solute segregation endows the rolled plate with excellent grain size stability and provides a prominent extra solute cluster strengthening,which completely resists the other softening effects including dislocation annihilation and grain coarsening.Meanwhile,the directional migration of Zn atoms and the annihilation of dislocations provide a"clear"space within the grain,which is beneficial for the moving and accumulating of subsequent dislocations.This work sheds light on the solute partitioning behavior and realizes a good application of GB segregation in improving the comprehensive mechanical properties of Mg alloys.展开更多
In order to investigate the segregation process and clarify its effect on the formation of TiN during the solidification of a micro-alloy steel containing titanium(Ti),a new mathematical model concerning solute transp...In order to investigate the segregation process and clarify its effect on the formation of TiN during the solidification of a micro-alloy steel containing titanium(Ti),a new mathematical model concerning solute transportation,solidification,as well as TiN precipitation was successfully established and verified.The transportation of solute elements was described using the Brody-Fleming microsegregation model,while the thermodynamic principles governing the precipitation of TiN were derived within the framework of the model.Additionally,the model accounts for variations in the diffusion coefficient due to phase transition and the influence of non-equilibrium solidification on solute distribution.High-temperature tests were conducted to validate the mathematical model.Results show that during solidification,due to selective crystallization,there is positive segregation of Ti and N in the solidifying front.What’s more,due to the high cooling rate near the surface of this steel,negative segregation is easier to be formed in the surface area.The highest concentration of TiN precipitation is found in the 1/4 width of this steel.High-temperature experiment shows that when the solidifying front reaches the 1/4 width of the specimen,the concentration product of Ti and N elements biased at the solidifying front reaches the thermodynamic conditions of TiN precipitation,and exists a higher concentration of TiN distributed in this region.To address this phenomenon,a comparative analysis of the effects of cooling rate and initial solute element content on TiN precipitation behavior was conducted.An increase in the surface cooling rate accelerates the progression of the solidification front and diminishes solute segregation near the front,thereby reducing TiN precipitation.However,with the increase of the initial solute element content,the concentration product of Ti and N elements rises,then the content of TiN precipitation increases.The results of this model provide important insight into the micro segregation and TiN precipitation mechanism of the micro-alloy steels bearing titanium.展开更多
Grain boundary segregation(GBS)of solutes influences the grain size,texture,and strength of Mg wrought alloys.So far,solutes'GBS in Mg has mostly been investigated by qualitative experimental observations.In this ...Grain boundary segregation(GBS)of solutes influences the grain size,texture,and strength of Mg wrought alloys.So far,solutes'GBS in Mg has mostly been investigated by qualitative experimental observations.In this work,we develop a quantitative model to compute the grain boundary segregation energy(ΔE_(seg))in binary Mg based alloys that takes the relative atomic density of GB into account.The model is utilized to computeΔE_(seg)of Al,Zn,Ca,Sn,Y,Gd,and Nd solutes in Mg.The result suggests that rare earth elements and Ca are more prone to GBS than Al,Zn,and Sn.Segregation of Gd solutes can explain the smaller grain size and slower grain growth in Mg-Gd extruded alloys than Mg-Al and Mg-Zn counterparts.It also provides an explanation for the weak extrusion texture in Mg-Gd.展开更多
Most studies on solute transport in coastal aquifers affected by tides focus on the transport of instantaneous released solute,and there are few studies on continuously released solute affected by tides.In this study,...Most studies on solute transport in coastal aquifers affected by tides focus on the transport of instantaneous released solute,and there are few studies on continuously released solute affected by tides.In this study,the image monitoring method is used to establish the quantitative relationship between the concentration of the colored tracer and the hue value of the image,and the digital image is used to determine the tracer concentration distribution.Using image monitoring method laboratory experiments,quantitative analysis of the characteristics of continuously released solute transport in coastal unconfined aquifers under the tidal influence.Experiments show that the high tide inhibits the increase in the concentration of each point in the aquifer.Under the influence of tides,the solute plume retreats towards the land.During the low tide period,the solute plume migrates toward the sea again.And the solute plume will maintain a relatively stable shape after entering the aquifer for a long enough time.Ignoring the tidal effect seems to have little effect on the estimation of the position of the solute plume,but ignoring the tidal effect has a certain influence on the estimation of the dispersion range of the solute plume.No matter whether considering the tidal action,the final dispersion range of the solute plume is almost the same.But before the solute plume reaches a stable state,ignoring the tidal effect will lead to a smaller dispersion range of the solute plume.展开更多
It is commonly recognized that the cooling rate has a substantial effect on solute partitioning and its resultant microsegregation during solidification.The classical dendrite tip undercooling theory clarifies the mit...It is commonly recognized that the cooling rate has a substantial effect on solute partitioning and its resultant microsegregation during solidification.The classical dendrite tip undercooling theory clarifies the mitigation of microsegregation by increasing the cooling rate.However,most of the studies focused on binary alloys,leaving an open question as to whether the microsegregation of different solutes in a multi-component alloy system exhibits a relieving degree similar to increasing cooling rate.Taking a widely used 6022-type Al alloy(Al-0.76Mg-0.93Si-0.2Fe)as a model alloy,the current study reveals that the microsegregation of Mg gets alleviated to the greatest extent,followed by those of Si and Fe when the cooling rate increases from 5 to 128 K/s.This phenomenon is attributed to the solute-based difference in response to partitioning to cooling rate(denoted as Rk).We propose a theoretical equation to quantify Rk,and the R_(k)values of solute Mg,Si,and Fe successfully explain the rank of solute partitioning in exper-iments.Furthermore,a broad range of R_(k)values of other commonly used alloying elements in Al alloys were calculated and ranked,delivering a handy tool to predict the microsegregation behavior and sol-ubility of different solute elements upon sub-rapid solidification,which is consistent with experimental observation.This framework can also be extended to other multi-component alloy systems.展开更多
The wadi dahab delta is in a dry, arid coastal zone within Egypt’s south Sinai Peninsula’s eastern portion. The primary water source is the Quaternary coastal alluvial aquifer. The groundwater salinity varies from 8...The wadi dahab delta is in a dry, arid coastal zone within Egypt’s south Sinai Peninsula’s eastern portion. The primary water source is the Quaternary coastal alluvial aquifer. The groundwater salinity varies from 890to 8213 mg/L, with a mean value of 3417 mg/L. The dissolved major ions have been used to calculate the seawater mixing index(SWMI) using a linear equation that discriminates the groundwater mostly affected by water–rock interaction(SWMI 1>) and other samples mixed with Seawater(SWMI < 1). The isotopic composition of groundwater for specifically chosen groundwater samples ranges from-0.645‰ to +5.212‰ for δ^(18)O and from-9.582‰ to + 22.778‰ for δ^(2)H, where the seawater represented by a Red Sea water sample(δ^(18)O + 1.64‰-δ^(2)H + 9.80‰) and reject brine water are considerably enriched the isotopic groundwater values. The geochemical NETPATH model constrained by the dissolved significant ions, isotopes, and the rock aquifer forming minerals as phases indicate the mixing percent with the seawater ranges from 9% to 97% of seawater from 91% to 3% of original recharge water. According to the SEAWAT 3-D flow models, seawater has penetrated the Northeastern Dahab delta aquifer, with the intrusion zone extending1500 m inland. The salt dissolution, upwelling of saline water, recharge from the upstream mountain block, and seawater encroachment are the primary aspects contributing to the deterioration of groundwater quality. These findings may have significance for effective groundwater withdrawal management in arid locations worldwide with similar hydrogeological systems.展开更多
A new Al−4.87Mn−1.42Mg−0.63Sc−0.20Zr(wt.%)alloy was fabricated by selective laser melting(SLM)and its microstructure and mechanical properties before and after aging were investigated.The results show that at a laser ...A new Al−4.87Mn−1.42Mg−0.63Sc−0.20Zr(wt.%)alloy was fabricated by selective laser melting(SLM)and its microstructure and mechanical properties before and after aging were investigated.The results show that at a laser power input of 300 W,increasing laser scanning speeds from 700 to 1500 mm/s improves the mechanical properties.In the meantime,the lattice distortion values increase from 0.15%to 0.31%,showing an increasing solute supersaturation.At a laser scanning speed of 1500 mm/s,the yield strength,ultimate tensile strength and elongation of the as-SLM alloys are 356 MPa,412 MPa and 17.7%,respectively.After aging at 350°C for 8 h,these values increase to 527 MPa,554 MPa and 10.4%,respectively.The contributions to the yield strength increments from the secondary Al6(Fe,Mn)needle-like phase and re-precipitated L12 structured Al6(Sc,Zr,Ti)nano-particles during aging are 74 and 79 MPa,respectively.As the aging temperature increases to 450°C,the dominant precipitation strengthening is attributed to the secondary Al6(Sc,Zr,Ti)nano-particles.展开更多
We analyze mimetic properties of a conservative finite-volume (FV) scheme on polygonal meshes used for modeling solute transport on a surface with variable elevation. Polygonal meshes not only provide enormous mesh ge...We analyze mimetic properties of a conservative finite-volume (FV) scheme on polygonal meshes used for modeling solute transport on a surface with variable elevation. Polygonal meshes not only provide enormous mesh generation flexibility, but also tend to improve stability properties of numerical schemes and reduce bias towards any particular mesh direction. The mathematical model is given by a system of weakly coupled shallow water and linear transport equations. The equations are discretized using different explicit cell-centered FV schemes for flow and transport subsystems with different time steps. The discrete shallow water scheme is well balanced and preserves the positivity of the water depth. We provide a rigorous estimate of a stable time step for the shallow water and transport scheme and prove a bounds-preserving property of the solute concentration. The scheme is second-order accurate over fully wet regions and first-order accurate over partially wet or dry regions. Theoretical results are verified with numerical experiments on rectangular, triangular, and polygonal meshes.展开更多
Niobium(Nb)is sensitive to even minute quantities of silicon(Si)solutes,which are known to induce pronounced hardening.However,the underlying mechanism for hardening remains elusive since the ef-fect of Si solutes on ...Niobium(Nb)is sensitive to even minute quantities of silicon(Si)solutes,which are known to induce pronounced hardening.However,the underlying mechanism for hardening remains elusive since the ef-fect of Si solutes on dislocation behavior is unclear.Here,using tensile testing,in-situ microscopy and nanomechanical testing,the behavior of dislocations in dilute Nb-Si alloys,containing from 0 at.%to 0.8 at.%Si,is investigated.We show that the hardness,strength and strain hardening rate increase from two to four times,while the uniform elongation in tension only reduces 50%as the Si content increases.Dislocations evolve from complex entangled patterns in Nb to parallel long-straight screw dislocation-dominated structures in Nb-Si alloys.In-situ indentation reveals that the origins of the marked harden-ing in Nb-Si alloy are the reduction of dislocation mobility and cross-slip propensity.Large densities of dislocation debris-superjogs and loops introduced throughout the sample during warm rolling and an-nealing are found to provide active internal dislocation sources,which explain the minimal ductility loss seen in these Nb-Si alloys.These findings can help guide the alloy design of high-performance refractory materials for extreme temperature applications.展开更多
Updated version of local non-equilibrium diffusion model （LNDM） for rapid solidification of binary alloys was considered. The LNDM takes into account deviation from local equilibrium of solute concentration and solu...Updated version of local non-equilibrium diffusion model （LNDM） for rapid solidification of binary alloys was considered. The LNDM takes into account deviation from local equilibrium of solute concentration and solute flux fields in bulk liquid. The exact solutions for solute concentration and flux in bulk liquid were obtained using hyperbolic diffusion equations. The results show the transition from diffusion-limited to purely thermally controlled solidification with effective diffusion coefficient →0 and complete solute trapping KLNDM（v）→1 at v→vDb for any kind of solid-liquid interface kinetics. Critical parameter for diffusionless solidification and complete solute trapping is the diffusion speed in bulk liquid vDb. Different models for solute trapping at the interface with different interface kinetic approaches were considered.展开更多
[ Objective] The purpose was to discuss drought resistance mechanism of Chenopodium album L. and supply theoretical basis and practical guidance for artificial cultivation and popularization of C. album. [ Method] C. ...[ Objective] The purpose was to discuss drought resistance mechanism of Chenopodium album L. and supply theoretical basis and practical guidance for artificial cultivation and popularization of C. album. [ Method] C. album seedlings grown to 6th leaf stage were conducted osmotic stress treatment with PEG6000 osmotic whose concentration was set up as 0, 5%, 10% and 20% and the various physiological indices of the 3rd -5th function leaves in upper plant were determined after being treated for 0, 1,3, 5, 7 and 9 d. [ Result] Under osmotic stress with 5% PGE, the relative water content （RWC） of C. album reduced less. Under osmotic stress with 10%, the RWC in seedling leaves of C. album decreased to 62% on the fifth day and the leaves began to wither. Under osmotic stress with 20%, the RWC in seedling leaves of C. album decreased to 61.9% on the third day and the leaves appeared withering, and the RWC decreased to 48.6% on the 7th day and the leaves were dry and yellow. Proline contents in seedling leaves of C. album under osmotic stress with 5%, 10% and 20% PEG were 7.64, 10.9 and 29.4 times of CK on the 7th day. [ Conclusion] C. album hed some adaptability to moderate osmotic stress, but the PEG osmotic stress with high concentration and long time might lead to severe damage on C. album.展开更多
Based on the microscopic phase-field model, ordered domain interfaces formed between D022 （Ni3V） phases along [001] direction in Ni75AlxV25-x alloys were simulated, and the effects of atomic structure on the migrati...Based on the microscopic phase-field model, ordered domain interfaces formed between D022 （Ni3V） phases along [001] direction in Ni75AlxV25-x alloys were simulated, and the effects of atomic structure on the migration characteristic and solute segregation of interfaces were studied. It is found that the migration ability is related to the atomic structure of interfaces, and three kinds of interfaces can migrate except the interface （001）//（002） which has the characteristic of L12 （Ni3Al） structure. V atoms jump to the nearest neighbor site and substitute for Ni, and vice versa. Because of the site selectivity behaviors of jumping atoms, the number of jumping atoms during the migration is the least and the jumping distance of atoms is the shortest among all possible modes, and the atomic structures of interfaces are unchanged before and after the migration. The preferences and degree of segregation or depletion of alloy elements are also related to the atomic structure of interface.展开更多
Poly(methacrylic acid co-poloxamer) hydrogel networks were synthesized by free radical solution polymerization and their equilibrium swelling and solute permeation properties were characterized. These gels exhibited p...Poly(methacrylic acid co-poloxamer) hydrogel networks were synthesized by free radical solution polymerization and their equilibrium swelling and solute permeation properties were characterized. These gels exhibited pH dependant swelling and solute diffusivity due to the formation or disruption of hydrogen bonded complexation between methacrylic acid (MAA) and etheric (EO). In neutral and basic conditions (above the swelling transition pH), the copolymer swelling was greatly higher than acid condition. In complexed hydrogels, the diffusion coefficients of vitamin B12 (VB12) were in the range of 10-10 to 10-7 cm2s-1; While in uncomplexed hydrogels, the values were about 210-6 cm2s-1. The comonomer composition and synthesis conditions have great effect on the structure, and thereby, swelling and solute diffusion characteristics of the resultant hydrogels. For the copolymers with composition of less than or more than 1:1 MAA/EO molar ratio, the plot of lnD vs 1/H-1 followed two different linear equations of 慺ree volume theory? respectively.展开更多
Based on the assumption that solute transport in a semi-infinite soil columnor in a field soil profile can be described by the boundary-layer method, an analytical solution ispresented for the advance of a solute fron...Based on the assumption that solute transport in a semi-infinite soil columnor in a field soil profile can be described by the boundary-layer method, an analytical solution ispresented for the advance of a solute front with time. The traditional convection-dispersionequation (CDE) subjected to two boundary conditions: 1) at the soil surface (or inlet boundary) and2) at the solute front, was solved using a Laplace transformation. A comparison of residentconcentrations using a boundary-layer method and an exact solution (in a semi-infinite-domain)showed that both were in good agreement within the range between the two boundaries. This led to anew method for estimating solute transport parameters in soils, requiring only observation ofadvance of the solute front with time. This may be corroborated visually using a tracer solutionwith marking-dye or measured utilizing time domain reflectometry (TDR). This method is applicable toboth laboratory soil columns and field soils. Thus, it could be a step forward for modeling solutetransport in field soils and for better understanding of the transport processes in soils.展开更多
基金supported by the National Natural Science Foundation of China(Nos.42007178 and 41907327)the Natural Science Foundation of Hubei(Nos.2020CFB463 and 2019CFB372)+4 种基金China Geological Survey(Nos.DD20160304 and DD20190824)Fundamental Research Funds for the Central Universities(Nos.CUG 190644 and CUGL180817)National Key Research and Development Program(No.2019YFC1805502)Key Laboratory of Karst Dynamics,MNR and GZAR(Institute of Karst Geology,CAGS)Guilin(No.KDL201703)Key Laboratory of Karst Ecosystem and Treatment of Rocky Desertification,MNR and IRCK by UNESCO(No.KDL201903)。
文摘To investigate groundwater flow and solute transport characteristics of the karst trough zone in China,tracer experiments were conducted at two adjacent typical karst groundwater flow systems(Yuquandong(YQD)and Migongquan(MGQ))in Sixi valley,western Hubei,China.Highresolution continuous monitoring was utilized to obtain breakthrough curves(BTCs),which were then analyzed using the multi-dispersion model(MDM)and the two-region nonequilibrium model(2RNE)with basic parameters calculated by CXTFIT and QTRACER2.Results showed that:(1)YQD flow system had a complex infiltration matrix with overland flow,conduit flow and fracture flow,while the MGQ flow system was dominated by conduit flow with fast flow transport velocity,but also small amount of fracture flow there;(2)They were well fitted based on the MDM(R^2=0.928)and 2RNE(R^2=0.947)models,indicating that they had strong adaptability in the karst trough zone;(3)conceptual models for YQD and MGQ groundwater systems were generalized.In YQD system,the solute was transported via overland flow during intense rainfall,while some infiltrated down into fissures and conduits.In MGQ system,most were directly transported to spring outlet in the fissureconduit network.
基金the funding from the Ger-man Research Foundation(DFG)-BE 5360/1-1 and ThyssenKrupp Europe.
文摘A microscopic understanding of the complex solute-defect interaction is pivotal for optimizing the alloy’s macroscopic mechanical properties.Simulating solute segregation in a plastically deformed crystalline system at atomic resolution remains challenging.The objective is to efficiently model and predict a phys-ically informed segregated solute distribution rather than simulating a series of diffusion kinetics.To ad-dress this objective,we coupled molecular dynamics(MD)and Monte Carlo(MC)methods using a novel method based on virtual atoms technique.We applied our MD-MC coupling approach to model off-lattice carbon(C)solute segregation in nanoindented Fe-C samples containing complex dislocation networks.Our coupling framework yielded the final configuration through efficient parallelization and localized en-ergy computations,showing C Cottrell atmospheres near dislocations.Different initial C concentrations resulted in a consistent trend of C atoms migrating from less crystalline distortion to high crystalline distortion regions.Besides unraveling the strong spatial correlation between local C concentration and defect regions,our results revealed two crucial aspects of solute segregation preferences:(1)defect ener-getics hierarchy and(2)tensile strain fields near dislocations.The proposed approach is generic and can be applied to other material systems as well.
基金supported by the stable support project and the Major National Science and Technology Project(2017-VII-0008-0101).
文摘With the evolution of nickel-based single crystal superalloys,there is an increase in heavy elements such as Re and Ru.This has made solutal convection more pronounced during the directional solidification process,leading to solute redistribution and increasing the risk of casting defects such as low-angle grain boundaries.To avoid casting defects,downward directional solidification(DWS)method is adopted to eliminate solutal convection and change solute redistribution.However,there is currently no in-situ characterization or quantitative simulation studying the solute redistribution during DWS and upward directional solidification(UWS)processes.A multicomponent phase field simulation coupled with lattice Boltzmann method was employed to quantitatively investigate changes in dendrite morphology,solutal convection and deviation of dendrite tips from the perspective of solute redistribution during UWS and DWS processes.The simulation of microstructure agrees well with the experimental results.The mechanism that explains how solutal convection affects side branching behavior is depicted.A novel approach is introduced to characterize dendrite deviation,elucidating the reasons why defects are prone to occur under the influence of natural convection and solute redistribution.
基金supported by National Key R&D Program of China(No.2022YFB3705202)National Natural Science Foundation of China(Nos.51831008,52171049 and 52104330).
文摘Second period elements(B,C,N,and O)usually appear at the grain boundary(GB)and strongly affect the mechanical performance in austenitic stainless steels.Therefore,it is significant to investigate the effect of solute elements(B,C,N,and O)on the GB.The first-principles calculation based on the density function theory was applied to explore the effect of B,C,N,and O onγ-FeΣ5(210)[001]GB.The GB energy,the segregation energy,the Voronoi volume,and the theoretical tensile test were calculated to investigate the segregation behavior and the strengthening effect.The structural change and electronic evolution were also investigated by bond change,charge density distribution,and density of states.The results show that B is favored to segregate at the capped trigonal prism(CTP)position with a large void and has a strengthening effect on the GB strength,while O and N are preferred to locate at the octahedral(OCT)site and have an embrittling effect on GB cohesion.C can segregate at both the CTP site and the OCT location with little energy difference.As C segregates at the OCT site,it is beneficial for GB strength.However,it is detrimental at the CTP position.It can be seen that the influence of solutes is closely related to the element type and segregated position.
基金supported by National Natural Science Foundation of China under Grant Nos.52234009 and 52274383Partial financial support came from the Fundamental Research Funds for the Central Universities,JLU,Program for JLU Science and Technology Innovative Research Team(JLUSTIRT,2017TD-09)Program for the Central University Youth Innovation Team.
文摘A novel core-shell structured Al_(8)Mn_(4)Y-Al_(2)Ca phase and controllable solute-segregation are elaborately designed in dilute Mg-0.6Al-0.5Mn-0.1Ca-0.1Y alloy(wt.%),via incomplete peritectic transformation during twin-roll casting.When soaked in 3.5 wt.%NaCl solution,Al_(2)Ca shell with a low electrochemical potential prevents direct contact of noble Al_(8)Mn_(4)Y with Mg matrix,mitigating the micro-galvanic corrosion and meanwhile accelerating the formation of uniform corrosion film.Thereafter,solute(Al,Ca)-segregation motivates the formation of heterogeneous multilayered corrosion product films,enhancing corrosion resistance and even achieving self-healing upon long-term corrosion.Notably,the dilute Mg alloy exhibits a corrosion rate as low as 0.22±0.05 mm·y^(−1).
基金supported by the National Natural Science Foundation of China(No.52225101)the Fundamental Research Funds for the Central Universities(2023CDJYXTD-002)+1 种基金supported by the Special Fund for Special Posts of Guizhou University(No.202353)Guizhou Provincial Basic Research Program(Natural Science)(Qingnian Yindao No.2024-123).
文摘Interface segregation of solute atoms has a profound effect on properties of engineering alloys.In this study,we report a novel strategy for breaking the strength-ductility dilemma of Mg alloy via solute segregation.The hot extruded Mg-1.8Gd-0.3Zr(wt.%)alloy sheet was subjected to three different passes of rolling,and then heat-treated at 200℃.The high-angle annular dark-field scanning transmission electron microscopy(HAADF-STEM)reveals a remarkable segregation of solute Gd atoms along high and low-angel grain boundaries(GBs).Under almost precipitation-free conditions,the strength and ductility of rolled alloy sheets are simultaneously improved after annealing.Especially for the annealed 3-passes-rolled specimen,the yield strength,ultimate tensile strength,and elongation are simultaneously increased by 11.2%,7.3%,and 18%,respectively.The solute segregation endows the rolled plate with excellent grain size stability and provides a prominent extra solute cluster strengthening,which completely resists the other softening effects,including dislocation annihilation and grain coarsening during the heating.Meanwhile,the directional migration of Gd atoms and the annihilation of dislocations provide a“clear”space within the grain,which is beneficial for the moving and accumulating of subsequent dislocations.This work sheds light on the solute partitioning behavior and realizes a good application of GB segregation in improving the comprehensive mechanical properties of Mg alloys.
基金Project supported by the National Natural Science Foundation of China(52301041)Guizhou Provincial Science and Technology Projects(Qingnian No.2024-123)the Special Fund for Special Posts of Guizhou University(2023-26,2023-53)。
文摘In this study,a novel strategy for breaking the strength-ductility dilemma of Mg-1.5Zn-0.6Gd(wt%)alloy via solute segregation was reported.The hot extruded alloy sheet was subjected to rolling deformation,and then heat-treated at 200℃.The high-angle annular dark-field scanning transmission electron microscopy(HAADF-STEM)reveals a remarkable segregation of solute Zn atoms along both high and lowangle grain boundaries(GBs).As compared with as-rolled plate,the yield strength,ultimate tensile strength,and the elongation of annealed sample is increased by 15.6%,14%,and 8.4%,respectively,acquiring an obvious strength-ductility synergy effect.The solute segregation endows the rolled plate with excellent grain size stability and provides a prominent extra solute cluster strengthening,which completely resists the other softening effects including dislocation annihilation and grain coarsening.Meanwhile,the directional migration of Zn atoms and the annihilation of dislocations provide a"clear"space within the grain,which is beneficial for the moving and accumulating of subsequent dislocations.This work sheds light on the solute partitioning behavior and realizes a good application of GB segregation in improving the comprehensive mechanical properties of Mg alloys.
基金supported by the National Natural Science Foundation of China(Grant Nos.52174321,52274339,52204348)the Jiangsu Achievement Transformation Fund Project(Grant No.SBA2023030047)the Postgraduate Research&Practice Innovation Program of Jiangsu Province(Grant No.KYCX24_3310).
文摘In order to investigate the segregation process and clarify its effect on the formation of TiN during the solidification of a micro-alloy steel containing titanium(Ti),a new mathematical model concerning solute transportation,solidification,as well as TiN precipitation was successfully established and verified.The transportation of solute elements was described using the Brody-Fleming microsegregation model,while the thermodynamic principles governing the precipitation of TiN were derived within the framework of the model.Additionally,the model accounts for variations in the diffusion coefficient due to phase transition and the influence of non-equilibrium solidification on solute distribution.High-temperature tests were conducted to validate the mathematical model.Results show that during solidification,due to selective crystallization,there is positive segregation of Ti and N in the solidifying front.What’s more,due to the high cooling rate near the surface of this steel,negative segregation is easier to be formed in the surface area.The highest concentration of TiN precipitation is found in the 1/4 width of this steel.High-temperature experiment shows that when the solidifying front reaches the 1/4 width of the specimen,the concentration product of Ti and N elements biased at the solidifying front reaches the thermodynamic conditions of TiN precipitation,and exists a higher concentration of TiN distributed in this region.To address this phenomenon,a comparative analysis of the effects of cooling rate and initial solute element content on TiN precipitation behavior was conducted.An increase in the surface cooling rate accelerates the progression of the solidification front and diminishes solute segregation near the front,thereby reducing TiN precipitation.However,with the increase of the initial solute element content,the concentration product of Ti and N elements rises,then the content of TiN precipitation increases.The results of this model provide important insight into the micro segregation and TiN precipitation mechanism of the micro-alloy steels bearing titanium.
基金supported by the National Key Research and Development Program of China(No.2021YFB3702602)the National Natural Science Foundation of China(Nos.51825101,52425101)。
文摘Grain boundary segregation(GBS)of solutes influences the grain size,texture,and strength of Mg wrought alloys.So far,solutes'GBS in Mg has mostly been investigated by qualitative experimental observations.In this work,we develop a quantitative model to compute the grain boundary segregation energy(ΔE_(seg))in binary Mg based alloys that takes the relative atomic density of GB into account.The model is utilized to computeΔE_(seg)of Al,Zn,Ca,Sn,Y,Gd,and Nd solutes in Mg.The result suggests that rare earth elements and Ca are more prone to GBS than Al,Zn,and Sn.Segregation of Gd solutes can explain the smaller grain size and slower grain growth in Mg-Gd extruded alloys than Mg-Al and Mg-Zn counterparts.It also provides an explanation for the weak extrusion texture in Mg-Gd.
基金supported by the National Natural Science Foundation of China(No.42172281)the Opening Fund of the State Key Laboratory of China University of Geosciences(Wuhan)(No.SKJ2018055)。
文摘Most studies on solute transport in coastal aquifers affected by tides focus on the transport of instantaneous released solute,and there are few studies on continuously released solute affected by tides.In this study,the image monitoring method is used to establish the quantitative relationship between the concentration of the colored tracer and the hue value of the image,and the digital image is used to determine the tracer concentration distribution.Using image monitoring method laboratory experiments,quantitative analysis of the characteristics of continuously released solute transport in coastal unconfined aquifers under the tidal influence.Experiments show that the high tide inhibits the increase in the concentration of each point in the aquifer.Under the influence of tides,the solute plume retreats towards the land.During the low tide period,the solute plume migrates toward the sea again.And the solute plume will maintain a relatively stable shape after entering the aquifer for a long enough time.Ignoring the tidal effect seems to have little effect on the estimation of the position of the solute plume,but ignoring the tidal effect has a certain influence on the estimation of the dispersion range of the solute plume.No matter whether considering the tidal action,the final dispersion range of the solute plume is almost the same.But before the solute plume reaches a stable state,ignoring the tidal effect will lead to a smaller dispersion range of the solute plume.
基金Financial support from the National Natural Science Foundation of China(Nos.52222409,52074132,U19A2084)the National Key Research and Development Program(No.2022YFE0122000)are greatly acknowledged.
文摘It is commonly recognized that the cooling rate has a substantial effect on solute partitioning and its resultant microsegregation during solidification.The classical dendrite tip undercooling theory clarifies the mitigation of microsegregation by increasing the cooling rate.However,most of the studies focused on binary alloys,leaving an open question as to whether the microsegregation of different solutes in a multi-component alloy system exhibits a relieving degree similar to increasing cooling rate.Taking a widely used 6022-type Al alloy(Al-0.76Mg-0.93Si-0.2Fe)as a model alloy,the current study reveals that the microsegregation of Mg gets alleviated to the greatest extent,followed by those of Si and Fe when the cooling rate increases from 5 to 128 K/s.This phenomenon is attributed to the solute-based difference in response to partitioning to cooling rate(denoted as Rk).We propose a theoretical equation to quantify Rk,and the R_(k)values of solute Mg,Si,and Fe successfully explain the rank of solute partitioning in exper-iments.Furthermore,a broad range of R_(k)values of other commonly used alloying elements in Al alloys were calculated and ranked,delivering a handy tool to predict the microsegregation behavior and sol-ubility of different solute elements upon sub-rapid solidification,which is consistent with experimental observation.This framework can also be extended to other multi-component alloy systems.
文摘The wadi dahab delta is in a dry, arid coastal zone within Egypt’s south Sinai Peninsula’s eastern portion. The primary water source is the Quaternary coastal alluvial aquifer. The groundwater salinity varies from 890to 8213 mg/L, with a mean value of 3417 mg/L. The dissolved major ions have been used to calculate the seawater mixing index(SWMI) using a linear equation that discriminates the groundwater mostly affected by water–rock interaction(SWMI 1>) and other samples mixed with Seawater(SWMI < 1). The isotopic composition of groundwater for specifically chosen groundwater samples ranges from-0.645‰ to +5.212‰ for δ^(18)O and from-9.582‰ to + 22.778‰ for δ^(2)H, where the seawater represented by a Red Sea water sample(δ^(18)O + 1.64‰-δ^(2)H + 9.80‰) and reject brine water are considerably enriched the isotopic groundwater values. The geochemical NETPATH model constrained by the dissolved significant ions, isotopes, and the rock aquifer forming minerals as phases indicate the mixing percent with the seawater ranges from 9% to 97% of seawater from 91% to 3% of original recharge water. According to the SEAWAT 3-D flow models, seawater has penetrated the Northeastern Dahab delta aquifer, with the intrusion zone extending1500 m inland. The salt dissolution, upwelling of saline water, recharge from the upstream mountain block, and seawater encroachment are the primary aspects contributing to the deterioration of groundwater quality. These findings may have significance for effective groundwater withdrawal management in arid locations worldwide with similar hydrogeological systems.
基金supported by the Science and Technology Innovation Program of Hunan Province,China(No.2023RC3055)the Natural Science Foundation of Hunan Province,China(Nos.2023JJ30671)+1 种基金the Natural Science Foundation of Changsha City,China(No.Kq2208264)the National Natural Science Foundation of China(No.51601229).
文摘A new Al−4.87Mn−1.42Mg−0.63Sc−0.20Zr(wt.%)alloy was fabricated by selective laser melting(SLM)and its microstructure and mechanical properties before and after aging were investigated.The results show that at a laser power input of 300 W,increasing laser scanning speeds from 700 to 1500 mm/s improves the mechanical properties.In the meantime,the lattice distortion values increase from 0.15%to 0.31%,showing an increasing solute supersaturation.At a laser scanning speed of 1500 mm/s,the yield strength,ultimate tensile strength and elongation of the as-SLM alloys are 356 MPa,412 MPa and 17.7%,respectively.After aging at 350°C for 8 h,these values increase to 527 MPa,554 MPa and 10.4%,respectively.The contributions to the yield strength increments from the secondary Al6(Fe,Mn)needle-like phase and re-precipitated L12 structured Al6(Sc,Zr,Ti)nano-particles during aging are 74 and 79 MPa,respectively.As the aging temperature increases to 450°C,the dominant precipitation strengthening is attributed to the secondary Al6(Sc,Zr,Ti)nano-particles.
基金This work was carried out under the auspices of the National Nuclear Security Administration of the U.S.Department of Energy at Los Alamos National Laboratory under Contract No.DE-AC52-06NA25396The Los Alamos unlimited release number is LA-UR-22-30864.
文摘We analyze mimetic properties of a conservative finite-volume (FV) scheme on polygonal meshes used for modeling solute transport on a surface with variable elevation. Polygonal meshes not only provide enormous mesh generation flexibility, but also tend to improve stability properties of numerical schemes and reduce bias towards any particular mesh direction. The mathematical model is given by a system of weakly coupled shallow water and linear transport equations. The equations are discretized using different explicit cell-centered FV schemes for flow and transport subsystems with different time steps. The discrete shallow water scheme is well balanced and preserves the positivity of the water depth. We provide a rigorous estimate of a stable time step for the shallow water and transport scheme and prove a bounds-preserving property of the solute concentration. The scheme is second-order accurate over fully wet regions and first-order accurate over partially wet or dry regions. Theoretical results are verified with numerical experiments on rectangular, triangular, and polygonal meshes.
基金supported by the National Natu-ral Science Foundation of China(Nos.51971170 and 51922082)the Shaanxi Science&Technology Innovation Project(No.2022QFY10-03)+1 种基金the assistance of Dr.Ping-Jiong Yang during the earlier stage of this project.S.O.and S.S.were supported by the Ministry of Education,Culture,Sport,Sci-ence and Technology of Japan programs(Nos.JPMXP1122684766,JPMXP1020230325,and JPMXP1020230327)JSPS KAKENHI(No.JP23H00161).S.S.was supported by JSPS KAKENHI(Nos.21K14042 and 22H05283).S.S.and S.O.wish to thank Dr.Tomo-hito Tsuru for discussions regarding NNP creation.
文摘Niobium(Nb)is sensitive to even minute quantities of silicon(Si)solutes,which are known to induce pronounced hardening.However,the underlying mechanism for hardening remains elusive since the ef-fect of Si solutes on dislocation behavior is unclear.Here,using tensile testing,in-situ microscopy and nanomechanical testing,the behavior of dislocations in dilute Nb-Si alloys,containing from 0 at.%to 0.8 at.%Si,is investigated.We show that the hardness,strength and strain hardening rate increase from two to four times,while the uniform elongation in tension only reduces 50%as the Si content increases.Dislocations evolve from complex entangled patterns in Nb to parallel long-straight screw dislocation-dominated structures in Nb-Si alloys.In-situ indentation reveals that the origins of the marked harden-ing in Nb-Si alloy are the reduction of dislocation mobility and cross-slip propensity.Large densities of dislocation debris-superjogs and loops introduced throughout the sample during warm rolling and an-nealing are found to provide active internal dislocation sources,which explain the minimal ductility loss seen in these Nb-Si alloys.These findings can help guide the alloy design of high-performance refractory materials for extreme temperature applications.
文摘Updated version of local non-equilibrium diffusion model （LNDM） for rapid solidification of binary alloys was considered. The LNDM takes into account deviation from local equilibrium of solute concentration and solute flux fields in bulk liquid. The exact solutions for solute concentration and flux in bulk liquid were obtained using hyperbolic diffusion equations. The results show the transition from diffusion-limited to purely thermally controlled solidification with effective diffusion coefficient →0 and complete solute trapping KLNDM（v）→1 at v→vDb for any kind of solid-liquid interface kinetics. Critical parameter for diffusionless solidification and complete solute trapping is the diffusion speed in bulk liquid vDb. Different models for solute trapping at the interface with different interface kinetic approaches were considered.
基金Supported by the Natural Science Foundation of Education Department of Jiangsu Province(02KJD18007)the Key Laboratory Program of Bio-re-sources of Jiangsu Province(KJS03042)the Key Program of Natural Science Foundation of Xuzhou Normal University(06XLA11)~~
文摘[ Objective] The purpose was to discuss drought resistance mechanism of Chenopodium album L. and supply theoretical basis and practical guidance for artificial cultivation and popularization of C. album. [ Method] C. album seedlings grown to 6th leaf stage were conducted osmotic stress treatment with PEG6000 osmotic whose concentration was set up as 0, 5%, 10% and 20% and the various physiological indices of the 3rd -5th function leaves in upper plant were determined after being treated for 0, 1,3, 5, 7 and 9 d. [ Result] Under osmotic stress with 5% PGE, the relative water content （RWC） of C. album reduced less. Under osmotic stress with 10%, the RWC in seedling leaves of C. album decreased to 62% on the fifth day and the leaves began to wither. Under osmotic stress with 20%, the RWC in seedling leaves of C. album decreased to 61.9% on the third day and the leaves appeared withering, and the RWC decreased to 48.6% on the 7th day and the leaves were dry and yellow. Proline contents in seedling leaves of C. album under osmotic stress with 5%, 10% and 20% PEG were 7.64, 10.9 and 29.4 times of CK on the 7th day. [ Conclusion] C. album hed some adaptability to moderate osmotic stress, but the PEG osmotic stress with high concentration and long time might lead to severe damage on C. album.
基金Projects (50941020, 10902086, 50875217, 20903075) supported by the National Natural Science Foundation of ChinaProjects (SJ08-ZT05, SJ08-B14) supported by the Natural Science Foundation of Shaanxi Province, ChinaProject (CX200905) supported by the Doctorate Foundation of Northwestern Polytechnical University, China
文摘Based on the microscopic phase-field model, ordered domain interfaces formed between D022 （Ni3V） phases along [001] direction in Ni75AlxV25-x alloys were simulated, and the effects of atomic structure on the migration characteristic and solute segregation of interfaces were studied. It is found that the migration ability is related to the atomic structure of interfaces, and three kinds of interfaces can migrate except the interface （001）//（002） which has the characteristic of L12 （Ni3Al） structure. V atoms jump to the nearest neighbor site and substitute for Ni, and vice versa. Because of the site selectivity behaviors of jumping atoms, the number of jumping atoms during the migration is the least and the jumping distance of atoms is the shortest among all possible modes, and the atomic structures of interfaces are unchanged before and after the migration. The preferences and degree of segregation or depletion of alloy elements are also related to the atomic structure of interface.
文摘Poly(methacrylic acid co-poloxamer) hydrogel networks were synthesized by free radical solution polymerization and their equilibrium swelling and solute permeation properties were characterized. These gels exhibited pH dependant swelling and solute diffusivity due to the formation or disruption of hydrogen bonded complexation between methacrylic acid (MAA) and etheric (EO). In neutral and basic conditions (above the swelling transition pH), the copolymer swelling was greatly higher than acid condition. In complexed hydrogels, the diffusion coefficients of vitamin B12 (VB12) were in the range of 10-10 to 10-7 cm2s-1; While in uncomplexed hydrogels, the values were about 210-6 cm2s-1. The comonomer composition and synthesis conditions have great effect on the structure, and thereby, swelling and solute diffusion characteristics of the resultant hydrogels. For the copolymers with composition of less than or more than 1:1 MAA/EO molar ratio, the plot of lnD vs 1/H-1 followed two different linear equations of 慺ree volume theory? respectively.
基金Project supported by the National Key Basic Research Support Foundation of China (No. 2000018605) the National Natural Science Foundation of China (Nos. 40025106 and 40371060).
文摘Based on the assumption that solute transport in a semi-infinite soil columnor in a field soil profile can be described by the boundary-layer method, an analytical solution ispresented for the advance of a solute front with time. The traditional convection-dispersionequation (CDE) subjected to two boundary conditions: 1) at the soil surface (or inlet boundary) and2) at the solute front, was solved using a Laplace transformation. A comparison of residentconcentrations using a boundary-layer method and an exact solution (in a semi-infinite-domain)showed that both were in good agreement within the range between the two boundaries. This led to anew method for estimating solute transport parameters in soils, requiring only observation ofadvance of the solute front with time. This may be corroborated visually using a tracer solutionwith marking-dye or measured utilizing time domain reflectometry (TDR). This method is applicable toboth laboratory soil columns and field soils. Thus, it could be a step forward for modeling solutetransport in field soils and for better understanding of the transport processes in soils.
