AsSb alloy(0.70−95.81 wt.%As)was prepared by electrodeposition in As(III)and Sb(III)contained electrolytes.The influence of electrolyte composition,hydrochloric acid concentration,and temperature on the composition an...AsSb alloy(0.70−95.81 wt.%As)was prepared by electrodeposition in As(III)and Sb(III)contained electrolytes.The influence of electrolyte composition,hydrochloric acid concentration,and temperature on the composition and structure of AsSb deposits was studied.The electroreduction mechanism of As(III)and Sb(III)in hydrochloric acid solution was revealed via thermodynamic analysis.The results show that the increase of H+concentration promotes the reduction of As(III),while the increase of Cl^(−)concentration significantly inhibits the reduction of Sb(III).As a result,the As content in deposits increases gradually with the increase of hydrochloric acid concentration.Simultaneously,the phase structure of AsSb deposits evolves from crystalline to amorphous.When the As content is 24.55−33.75 wt.%,AsSb mixed crystal is obtained.The electrolysis temperature has little effect on the deposits composition,but the structure of deposits evolves from crystalline to amorphous with decreasing the temperature.展开更多
Honey is a product of the elaboration of flower nectar by bees. The general features and elemental composition of honey depend on its botanical origin. In this study, five color parameters (L*: lightness, a*: red...Honey is a product of the elaboration of flower nectar by bees. The general features and elemental composition of honey depend on its botanical origin. In this study, five color parameters (L*: lightness, a*: red color, b*: yellow color, C*ab and hab) and five elements (Na, K, Mg, Ca and Zn) were determined and related with 91 Thai honey samples. The origins of four botanic types of (1) longan flower (Dimocarpus sp.), (2) lynchee flower (Litchi sp.), (3) sunflower (Helianthus sp.) and (4) wild flower (Eupatorium sp.) using principle component analysis (PCA). The results showed that five color parameters and five metal contents related with the Thai botanic origins of the honeys using principle component analysis (PCA). Six major indicators of PC i (variance is 44.33%) from three color parameters are L*(-0.926), a*(0.927) and hue or hab (0.824) and from three metal contents are K(0.833), Ca(0.816) and Mg(0.595). Two minor indicators of PC2 (variance is 21.58%) from color parameters are b*(-0.934) and Chroma or C*ab (-0.834). Two indicators of PC3 (%variance is 12.47%) from contents of Na (-0.722) and Zn (0.704). Thai Lynchee (C) flower honeys classified using both six parameters in PC 1 and two color parameters in PC2. Thai longan flower (G) honeys classified using the contents of Zn and Na in PC3 parameters. Thai sunflower (S) honeys classified using two color parameters in PC2. Thai wild flower (W) honeys classified using the metal contents of K in PC 1 parameter, Zn and Na in PC3 parameters.展开更多
The vacuum brazing of TiAl based alloy with 40Cr steel was investigated using Ag-Cu-Ti filler metal. The experimental results show that the Ag, Cu, Ti atoms in the filler metal and the base metal inter-diffuse toward ...The vacuum brazing of TiAl based alloy with 40Cr steel was investigated using Ag-Cu-Ti filler metal. The experimental results show that the Ag, Cu, Ti atoms in the filler metal and the base metal inter-diffuse toward each other during brazing and react at the interface to form an inter-metallic AlCu 2Ti compound which joins two parts to produce a brazing joint with higher strength.展开更多
基金The authors are grateful for the financial supports from the National Natural Science Foundation of China(No.51374185).
文摘AsSb alloy(0.70−95.81 wt.%As)was prepared by electrodeposition in As(III)and Sb(III)contained electrolytes.The influence of electrolyte composition,hydrochloric acid concentration,and temperature on the composition and structure of AsSb deposits was studied.The electroreduction mechanism of As(III)and Sb(III)in hydrochloric acid solution was revealed via thermodynamic analysis.The results show that the increase of H+concentration promotes the reduction of As(III),while the increase of Cl^(−)concentration significantly inhibits the reduction of Sb(III).As a result,the As content in deposits increases gradually with the increase of hydrochloric acid concentration.Simultaneously,the phase structure of AsSb deposits evolves from crystalline to amorphous.When the As content is 24.55−33.75 wt.%,AsSb mixed crystal is obtained.The electrolysis temperature has little effect on the deposits composition,but the structure of deposits evolves from crystalline to amorphous with decreasing the temperature.
文摘Honey is a product of the elaboration of flower nectar by bees. The general features and elemental composition of honey depend on its botanical origin. In this study, five color parameters (L*: lightness, a*: red color, b*: yellow color, C*ab and hab) and five elements (Na, K, Mg, Ca and Zn) were determined and related with 91 Thai honey samples. The origins of four botanic types of (1) longan flower (Dimocarpus sp.), (2) lynchee flower (Litchi sp.), (3) sunflower (Helianthus sp.) and (4) wild flower (Eupatorium sp.) using principle component analysis (PCA). The results showed that five color parameters and five metal contents related with the Thai botanic origins of the honeys using principle component analysis (PCA). Six major indicators of PC i (variance is 44.33%) from three color parameters are L*(-0.926), a*(0.927) and hue or hab (0.824) and from three metal contents are K(0.833), Ca(0.816) and Mg(0.595). Two minor indicators of PC2 (variance is 21.58%) from color parameters are b*(-0.934) and Chroma or C*ab (-0.834). Two indicators of PC3 (%variance is 12.47%) from contents of Na (-0.722) and Zn (0.704). Thai Lynchee (C) flower honeys classified using both six parameters in PC 1 and two color parameters in PC2. Thai longan flower (G) honeys classified using the contents of Zn and Na in PC3 parameters. Thai sunflower (S) honeys classified using two color parameters in PC2. Thai wild flower (W) honeys classified using the metal contents of K in PC 1 parameter, Zn and Na in PC3 parameters.
文摘The vacuum brazing of TiAl based alloy with 40Cr steel was investigated using Ag-Cu-Ti filler metal. The experimental results show that the Ag, Cu, Ti atoms in the filler metal and the base metal inter-diffuse toward each other during brazing and react at the interface to form an inter-metallic AlCu 2Ti compound which joins two parts to produce a brazing joint with higher strength.