如何评价开发的新型材料是否适合在室温磁制冷机中使用,有不同的看法。将最近报道的有影响的磁制冷材料如Gd Si Ge系列合金,La Fe Si系列合金与金属钆进行对比,说明不能仅仅根据等温磁熵变的数据判断它是否适用于磁制冷机中。应该以金...如何评价开发的新型材料是否适合在室温磁制冷机中使用,有不同的看法。将最近报道的有影响的磁制冷材料如Gd Si Ge系列合金,La Fe Si系列合金与金属钆进行对比,说明不能仅仅根据等温磁熵变的数据判断它是否适用于磁制冷机中。应该以金属钆作为室温磁制冷材料的基准材料,全面评定各个新开发的磁制冷材料的绝热温变、使用温度区间、单位体积磁熵变等参数。数据说明,金属钆在综合性能上具有优势,是目前室温磁制冷机主要采用的磁制冷剂。展开更多
The thermal stability of the rare earth rich phase particles in α, α+β and β phase regions of Ti 5Al 4Sn 2Zr 1Mo 0 25Si 1Nd(Ti 55) high temperature titanium alloy heat treated was studied. Under ...The thermal stability of the rare earth rich phase particles in α, α+β and β phase regions of Ti 5Al 4Sn 2Zr 1Mo 0 25Si 1Nd(Ti 55) high temperature titanium alloy heat treated was studied. Under conditions of 600～980 ℃/1～100 h and 1050～1500 ℃/1～10 h, the average particle size ranges from 3 34 to 4 20 μm, the circularity shape factor from 0 619 to 0 759, and the volume fraction from 1 4% to 1 8%. The results show that nearly no change is found for the size, shape, and volume fraction of the particles in the alloy, and the rare earth rich phase particles exhibit thermal stability.展开更多
We have studied the effect of hole-doping on the established scenerio of the first-order Mott metal-insulatortransition (MIT) at half-filling using dynamical mean-Seld theory and exact diagonalization technique. The M...We have studied the effect of hole-doping on the established scenerio of the first-order Mott metal-insulatortransition (MIT) at half-filling using dynamical mean-Seld theory and exact diagonalization technique. The Mott insu-lator state is changed into metallic state immediately as holes are doped into the system. The latter is expected to beFermi liquid. The previously found unanalytical structure of MIT no longer exists for doping as small as 2 percent. Wecompare our results with that obtained from Gutzwiller approximation.展开更多
文摘如何评价开发的新型材料是否适合在室温磁制冷机中使用,有不同的看法。将最近报道的有影响的磁制冷材料如Gd Si Ge系列合金,La Fe Si系列合金与金属钆进行对比,说明不能仅仅根据等温磁熵变的数据判断它是否适用于磁制冷机中。应该以金属钆作为室温磁制冷材料的基准材料,全面评定各个新开发的磁制冷材料的绝热温变、使用温度区间、单位体积磁熵变等参数。数据说明,金属钆在综合性能上具有优势,是目前室温磁制冷机主要采用的磁制冷剂。
文摘The thermal stability of the rare earth rich phase particles in α, α+β and β phase regions of Ti 5Al 4Sn 2Zr 1Mo 0 25Si 1Nd(Ti 55) high temperature titanium alloy heat treated was studied. Under conditions of 600～980 ℃/1～100 h and 1050～1500 ℃/1～10 h, the average particle size ranges from 3 34 to 4 20 μm, the circularity shape factor from 0 619 to 0 759, and the volume fraction from 1 4% to 1 8%. The results show that nearly no change is found for the size, shape, and volume fraction of the particles in the alloy, and the rare earth rich phase particles exhibit thermal stability.
文摘We have studied the effect of hole-doping on the established scenerio of the first-order Mott metal-insulatortransition (MIT) at half-filling using dynamical mean-Seld theory and exact diagonalization technique. The Mott insu-lator state is changed into metallic state immediately as holes are doped into the system. The latter is expected to beFermi liquid. The previously found unanalytical structure of MIT no longer exists for doping as small as 2 percent. Wecompare our results with that obtained from Gutzwiller approximation.
