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
In order to improve the corrosion and mechanical properties of AM50 magnesium alloy, 1 wt.% Gd was used to modify the AM50 magnesium alloy. The microstructure, corrosion and mechanical properties were evaluated by X-r...In order to improve the corrosion and mechanical properties of AM50 magnesium alloy, 1 wt.% Gd was used to modify the AM50 magnesium alloy. The microstructure, corrosion and mechanical properties were evaluated by X-ray diffraction （XRD）, scanning electron microscopy （SEM）, energy dispersive spectroscopy （EDS）, electrochemical and mechanical stretch methods. The results indicated that β-Mg17Al12 phase decreased and Al2Gd3 and Al0.4GdMn1.6 phase existed after Gd addition. Because of the Gd addition, the grain of AM50 magnesium alloy was refined significantly, which improved the tensile strength of AM50 magnesium al-loy. The decreasing ofβ phase improved the corrosion resistance of the magnesium alloy. The fracture mechanism of the Gd modified AM50 magnesium alloy was quasi-cleavage fracture. The corrosion residual strength （CRS） of AM50 magnesium alloy was im-proved after 1 wt.% Gd addition.展开更多
To investigate the expression of apoptosis-related protein(Fas,FasL,and Bcl-2)in the pathogenesis of autoimmune thyroid disorders (ATDs),immunohistochemical staining was performed on 20 Hashimoto's thyroiditis(HT)...To investigate the expression of apoptosis-related protein(Fas,FasL,and Bcl-2)in the pathogenesis of autoimmune thyroid disorders (ATDs),immunohistochemical staining was performed on 20 Hashimoto's thyroiditis(HT),20 Graves'disease(GD),and 20 thyroid follicular adenoma(TFA,as control).All the cases expressed Fas,mainly on the cell surface and cytoplasm.FasL was found in 17 cases of the TFA.Bcl-2 was detected in 15 cases of HT,19 of GD and 17 of TFA.In TFA,a moderate Fas expression and a minimal or no FasL expression was detected on follicular cells.In HT,the follicles adjacent to infiltrating lymphocytes showed increased levels of Fas and FasL expression.A weaker staining of Fas and FasL was exhibited on infiltrating lymphocytes than on thyrocytes.In a comparison of GD with HT,thyrocytes and lymphocytes showed similar Fas staining,but for FasL the staining was rather weaker in HT.The expression of Bcl-2 was nearly identical in GD and TFA,but much weaker on the follicular cells in vicinity of lymphocytes and on the lymphocytes located in germinal centers of HT tissues.The expression of Fas,FasL,Bcl-2 in Hashimoto's thyroiditis and Graves' disease were almost same.FasL strong expression and Bcl-2 weak expression on the follicles in HT may induce apoptosis.These results provided evidence for expression of Fas,FasL and Bcl-2 in the pathogenesis of autoimmune thyroid disease.The lymphocytes seem not to be directly engaged in the process via their own FasL,but they may provide some cytokines that,in turn,upregulate Fas and/or FasL expression to induce apoptosis.Cellular & Molecular Immunology.2004;1(3):224-228.展开更多
The effects of Ce, Y and Gd additions on the as-cast microstructure and mechanical properties of Mg-3Sn-1Mn alloy were investigated and compared by using optical and electron microscopies, X-ray diffraction analysis, ...The effects of Ce, Y and Gd additions on the as-cast microstructure and mechanical properties of Mg-3Sn-1Mn alloy were investigated and compared by using optical and electron microscopies, X-ray diffraction analysis, and tensile and creep tests. The results indicated that the microstructure of the Mg-3Sn-1Mn alloy with the addition of 0.87 wt.%Ce was refined while the microstructures of the alloys with the additions of 0.79 wt.%Y or 0.84 wt.%Gd were coarsened. Furthermore, adding 0.87 wt.%Ce to the Mg-3Sn-1Mn alloy could improve the tensile properties while adding 0.79 wt.%Y or 0.84 wt.%Gd gave a detrimental effects on the tensile properties. In addition, adding 0.87 wt.%Ce, 0.79 wt.%Y and 0.84 wt.%Gd to the Mg-3Sn-1Mn alloy could improve the creep properties. Among the three additions, the addition of 0.87 wt.%Ce was more suitable to further improve the strength and creep performance of the Mg-3Sn-1Mn alloy.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。
基金Project supported by National Natural Science Foundation of China(51201068)Science and Technology Development Projects of Jilin Province(201201032)Science and Technology Development of Changchun City(11KZ31)
文摘In order to improve the corrosion and mechanical properties of AM50 magnesium alloy, 1 wt.% Gd was used to modify the AM50 magnesium alloy. The microstructure, corrosion and mechanical properties were evaluated by X-ray diffraction （XRD）, scanning electron microscopy （SEM）, energy dispersive spectroscopy （EDS）, electrochemical and mechanical stretch methods. The results indicated that β-Mg17Al12 phase decreased and Al2Gd3 and Al0.4GdMn1.6 phase existed after Gd addition. Because of the Gd addition, the grain of AM50 magnesium alloy was refined significantly, which improved the tensile strength of AM50 magnesium al-loy. The decreasing ofβ phase improved the corrosion resistance of the magnesium alloy. The fracture mechanism of the Gd modified AM50 magnesium alloy was quasi-cleavage fracture. The corrosion residual strength （CRS） of AM50 magnesium alloy was im-proved after 1 wt.% Gd addition.
文摘To investigate the expression of apoptosis-related protein(Fas,FasL,and Bcl-2)in the pathogenesis of autoimmune thyroid disorders (ATDs),immunohistochemical staining was performed on 20 Hashimoto's thyroiditis(HT),20 Graves'disease(GD),and 20 thyroid follicular adenoma(TFA,as control).All the cases expressed Fas,mainly on the cell surface and cytoplasm.FasL was found in 17 cases of the TFA.Bcl-2 was detected in 15 cases of HT,19 of GD and 17 of TFA.In TFA,a moderate Fas expression and a minimal or no FasL expression was detected on follicular cells.In HT,the follicles adjacent to infiltrating lymphocytes showed increased levels of Fas and FasL expression.A weaker staining of Fas and FasL was exhibited on infiltrating lymphocytes than on thyrocytes.In a comparison of GD with HT,thyrocytes and lymphocytes showed similar Fas staining,but for FasL the staining was rather weaker in HT.The expression of Bcl-2 was nearly identical in GD and TFA,but much weaker on the follicular cells in vicinity of lymphocytes and on the lymphocytes located in germinal centers of HT tissues.The expression of Fas,FasL,Bcl-2 in Hashimoto's thyroiditis and Graves' disease were almost same.FasL strong expression and Bcl-2 weak expression on the follicles in HT may induce apoptosis.These results provided evidence for expression of Fas,FasL and Bcl-2 in the pathogenesis of autoimmune thyroid disease.The lymphocytes seem not to be directly engaged in the process via their own FasL,but they may provide some cytokines that,in turn,upregulate Fas and/or FasL expression to induce apoptosis.Cellular & Molecular Immunology.2004;1(3):224-228.
基金Project supported by the National Natural Science Foundation of China (50725413), the National Basic Research Program of China (973) (2007CB613704)the Chongqing Science and Technology Program of China (2010AC4085, 2009AB4134 and 2006AA4012-9-6)the Pro-gram for Hundreds of Distinguished Leading Scientists of CQ CSTC (2010CSTC-HDLS)
文摘The effects of Ce, Y and Gd additions on the as-cast microstructure and mechanical properties of Mg-3Sn-1Mn alloy were investigated and compared by using optical and electron microscopies, X-ray diffraction analysis, and tensile and creep tests. The results indicated that the microstructure of the Mg-3Sn-1Mn alloy with the addition of 0.87 wt.%Ce was refined while the microstructures of the alloys with the additions of 0.79 wt.%Y or 0.84 wt.%Gd were coarsened. Furthermore, adding 0.87 wt.%Ce to the Mg-3Sn-1Mn alloy could improve the tensile properties while adding 0.79 wt.%Y or 0.84 wt.%Gd gave a detrimental effects on the tensile properties. In addition, adding 0.87 wt.%Ce, 0.79 wt.%Y and 0.84 wt.%Gd to the Mg-3Sn-1Mn alloy could improve the creep properties. Among the three additions, the addition of 0.87 wt.%Ce was more suitable to further improve the strength and creep performance of the Mg-3Sn-1Mn alloy.
