Planning and Design of Suocao Bay Wetland Park in Maoji Experimental Area of Huainan City

The coal resources are abundant in Huainan City,but with development and utilization of coal mine,the water surface formed by mining subsidence increases gradually,and more and more people pay great attention on the research of the wetland in the subsidence area. Through on-site review,the status of the wetland resources is explored,and wetland ecosystem of the region is analyzed. In this paper,the red line delimitation,functional zoning,overall layout and basic engineering planning and design of Suocao Bay Wetland Park are carried out. The planning and design of Suocao Bay Wetland Park mean to provide new support for ecological protection,accelerate the ecological restoration in Maoji Experimental Area,vigorously carry forward the wetland culture,and make it become an important wetland demonstration base in coal mine subsidence area.

Study on Biodiversity Conservation of Wetlands around the Chaohu Lake

There are many types of wetlands around the Chaohu Lake,and wetland biodiversity is rich. The protection of wetland biodiversity is of great significance for regional sustainable development. In this paper,the wetlands around the Chaohu Lake are taken as the research objects. Based on the investigation and analysis of the biodiversity in the wetlands,combing the threats to the biodiversity of the wetland around the Chaohu Lake at the present stage,the biodiversity protection countermeasures of the wetlands around the Chaohu Lake are put forward.

Revealing the influence of high magnetic field on the solute distribution during directional solidification of Al-Cu alloy

The effect of the high magnetic field(MF)on the distribution of solute concentration during directional solidification of Al-Cu alloy under low growth speed was experimentally investigated.The amount of nonequilibrium eutectic is quantified via X-ray computed tomography(XCT)and demonstrated to reduce with the application of MF.Further,experimental results reveal that the MF alleviates the microsegregation and increases the average Cu concentration in solid solution,leading to the increases of the effective partition coefficient ke.It was also found that Cu concentration in solid solution increases continuously with the increasing intensity of MF,following the strengthening of micro-hardness.The change of ke under the MF is demonstrated to attribute to the thermoelectric magnetic convection(TEMC)in the mushy zone and the thermoelectric magnetic force(TEMF)acting on the solid.The TEMC is supposed to cause secondary convection owing to the inequality in flow velocities of circulation in different positions of dendrite stem.And the vacancies created by the proliferation and movement of dislocations induced by TEMF in the matrix is supposed to be able to capture solute atoms and thus enhance the solute concentration in the solid solution.

Microstructure and mechanical properties of directionally solidified Al-rich Ni_(3)Al-based alloy under static magnetic field

The influence of a longitudinal static magnetic field on microstructures and mechanical properties of Ni_(3)Al-based alloy during directional solidification at the growth speed of 25μm/s and 100μm/s has been experimentally investigated.Results reflected that the utilization of a 0.5 T magnetic field refines the Ni Al dendrites at both speeds of growth.When applying a high magnetic field,the columnar-to-equiaxed transition(CET)occurred at growth speed of 25μm/s and dendrite networks formed at growth speed of 100μm/s.Tensile property results indicated that the refinement of dendrites enhanced both plasticity and ultimate tensile strength of Ni-Al alloy.The change of microstructures and mechanical properties should be attributed to the combined action of the thermoelectric magnetic convection(TEMC)in mushy zone together with the thermoelectric magnetic force(TEMF)acting on the solid.When applying a low magnetic field(0.5 T),the TEMF is too small to fragment the dendrites,and the refined dendrites is mainly due to the TEMC in the interdendritic regions.At a lower growth speed,the TEMF is supposed to strong enough to fragment the dendrites and induce the occurrence of CET under 2 or 4 T.When the growth speed increased to 100μm/s,no obvious CET was observed,but a vertical secondary convection is induced by the circulation in the parallel plane,which promotes the growth of secondary and tertiary branches,leading to the formation of abnormally developed high order dendrites.The hierarchical dendritic structure was suggested to provide a channel for rapid crack propagation and thus degraded the mechanical properties.

Revealing the Diversity of Dendritic Morphology Evolution During Solidification of Magnesium Alloys using Synchrotron X-ray Imaging:A Review

In this paper,the diversity of complicated dendrite microstructure and its evolution behavior during solidification in different magnesium alloys under various processing conditions were illustrated using synchrotron X-ray imaging technique.A variety of dendritic morphologies and branching structures were revealed,i.e.,sixfold plate-like symmetric structure in Mg-Al-based structure,12-branch structure in Mg-Zn-based alloys and 18-branch structure in Mg-Sn-and Mg-Ca-based alloys as well as seaweed like hyper-branched structure in Mg-38wt%Zn alloy.In addition,a dendrite morphology and orientation transition with increasing addition of Zn content were also observed in Mg-Zn alloy,with dendrite growth pattern transform from anisotropy(low Zn addition)with sixfold symmetric snow-flake structure to relative isotropy(intermediate Zn addition)where seaweed morphology presented and then back to anisotropy(high Zn addition)when only 12 branches with preferred<11 2 1>orientations were observed.The phase-field model representing the typical dendritic morphologies and branching structures under various conditions was also depicted and discussed.Further,the two-dimensional(2D)real-time dendrite growth dynamics in different Mg-based alloys captured using synchrotron X-ray radiography for unveiling the originate of theα-Mg dendrite was reviewed.Following this,the four-dimensional(3D+time)synchrotron X-ray tomographic in situ observation of dendritic morphology evolution indicating the formation mechanism of the diverse dendritic morphology during Mg-Sn-and Mg-Zn-based alloys was also summarized.Finally,the future study on exploring the complicated dendritic morphologies and their origination during solidification of Mg-based alloys is prospected.