This paper analyzes the characteristics of BRICS＇s agricultural trading in four ways： export market competition, revealed comparative advantage, trade specialization index, and export similarity index. It shows that...This paper analyzes the characteristics of BRICS＇s agricultural trading in four ways： export market competition, revealed comparative advantage, trade specialization index, and export similarity index. It shows that BRICS countries export different agricultural goods in the same market, so they do not have real competition in agricultural trading markets. BRICS countries have a comparative advantage in different products; especially Brazil with having total different RCA products. In BRICS countries, China and Brazil are the closest trading partners. Compared with other BRICS countries, China and India have a higher similarity in agricultural trading.展开更多
In this paper, the Au nanoparticles and rare-earth （RE） upconversion nanoparticles （NPs） were respectively synthesized by using polyelectrolyte as the capping agents. Since the synthesized Au NPs and RE NPs had th...In this paper, the Au nanoparticles and rare-earth （RE） upconversion nanoparticles （NPs） were respectively synthesized by using polyelectrolyte as the capping agents. Since the synthesized Au NPs and RE NPs had the similar size and surface conditions, Their mixture were employed in a pH sensing application. Benefited from the good spectral overlap between the RE upconversion emission bands and pH-tunable surface plasmon bands of the Au NPs, the pH-induced manipulation of green-to-red emission intensity ratio of the upconversion fluorescence was achieved in the Au-RE mixture. The results demonstrate a rapid ratiometric approach for pH sensing, which is more efficient than traditional sensing methods that depend on single intensity-based responses to analytes.展开更多
文摘This paper analyzes the characteristics of BRICS＇s agricultural trading in four ways： export market competition, revealed comparative advantage, trade specialization index, and export similarity index. It shows that BRICS countries export different agricultural goods in the same market, so they do not have real competition in agricultural trading markets. BRICS countries have a comparative advantage in different products; especially Brazil with having total different RCA products. In BRICS countries, China and Brazil are the closest trading partners. Compared with other BRICS countries, China and India have a higher similarity in agricultural trading.
基金Supported by grants from the Natural Science Foundation of Jiangsu Province(SBK201240182)the Natural Science Foundation of China(J1210061)
文摘In this paper, the Au nanoparticles and rare-earth （RE） upconversion nanoparticles （NPs） were respectively synthesized by using polyelectrolyte as the capping agents. Since the synthesized Au NPs and RE NPs had the similar size and surface conditions, Their mixture were employed in a pH sensing application. Benefited from the good spectral overlap between the RE upconversion emission bands and pH-tunable surface plasmon bands of the Au NPs, the pH-induced manipulation of green-to-red emission intensity ratio of the upconversion fluorescence was achieved in the Au-RE mixture. The results demonstrate a rapid ratiometric approach for pH sensing, which is more efficient than traditional sensing methods that depend on single intensity-based responses to analytes.
