Oxychalcogenides have been drawn much attention to be explored as nonlinear optical(NLO)materials in recent years.To date,all the NLO oxychalcogenides crystallize in low dimensional structures.Herein,a new oxysulfide ...Oxychalcogenides have been drawn much attention to be explored as nonlinear optical(NLO)materials in recent years.To date,all the NLO oxychalcogenides crystallize in low dimensional structures.Herein,a new oxysulfide K_(2)Ba_(0.5)Ga_(9)O_(2)S_(13) was obtained via three-dimensional(3D){[Ga_(9)O_(2)S_(13)]^(3-)}_(∞)polyanionic framework.As the first oxychalcogenide with 3D NLO-acitve polyanionic framework,K_(2)Ba_(0.5)Ga_(9)O_(2)S_(13) has a wide band gap of 3.72 eV,and exhibits a high laser-induced damage threshold(LIDT,17×AgGaS_(2)).It presents moderate phase-matchable NLO response of 0.5×AgGaS_(2) at 2.1μm and 2×KH_(2)PO_(4) at 1.064μm.The theoretical calculation results indicate that the NLO response is mainly contributed from[Ga(2)S4]unit-built[Ga(2)_(3)S_(10)]windmill-like motif.This work may stimulate the exploration of more NLO oxychalcogenides with balanced performances.展开更多
The microstructure and mechanical properties of Mg–6Zn–1Y and Mg–6Zn–3Y（wt%） alloys under different cooling rates were investigated. The results show that the second dendrite arm spacing（SDAS） of Mg–6Zn–1Y a...The microstructure and mechanical properties of Mg–6Zn–1Y and Mg–6Zn–3Y（wt%） alloys under different cooling rates were investigated. The results show that the second dendrite arm spacing（SDAS） of Mg–6Zn–1Y and Mg–6Zn–3Y is reduced by 32 and 30% with increasing cooling rates（Rc） from 10.2 to 23 K/s, which can be predicted using a empirical model of SDAS=68 R 0：45：45cand SDAS=73 R 0c, respectively. The compressive strength of both alloys increases with increasing the cooling rate, which is attributed to the increase of volume fraction（Vf） of secondary phases under high cooling rate. The interaction of the cooling rate and component with SDAS has been theoretically analyzed using interdependence theory.展开更多
基金support by the National Natural Science Foundation of China(21771159,22071212)Qinglan Project of Jiangsu Province of China.
文摘Oxychalcogenides have been drawn much attention to be explored as nonlinear optical(NLO)materials in recent years.To date,all the NLO oxychalcogenides crystallize in low dimensional structures.Herein,a new oxysulfide K_(2)Ba_(0.5)Ga_(9)O_(2)S_(13) was obtained via three-dimensional(3D){[Ga_(9)O_(2)S_(13)]^(3-)}_(∞)polyanionic framework.As the first oxychalcogenide with 3D NLO-acitve polyanionic framework,K_(2)Ba_(0.5)Ga_(9)O_(2)S_(13) has a wide band gap of 3.72 eV,and exhibits a high laser-induced damage threshold(LIDT,17×AgGaS_(2)).It presents moderate phase-matchable NLO response of 0.5×AgGaS_(2) at 2.1μm and 2×KH_(2)PO_(4) at 1.064μm.The theoretical calculation results indicate that the NLO response is mainly contributed from[Ga(2)S4]unit-built[Ga(2)_(3)S_(10)]windmill-like motif.This work may stimulate the exploration of more NLO oxychalcogenides with balanced performances.
基金financially supported by the National Natural Science Foundation of China (NO. 51464034)the Cooperation and Exchanges of Nanchang City (2012DWHZXCL@JDYTH-001)+5 种基金the Educational Commission of Jiangxi Province (No. GJJ13069)the Innovation Fund Designated for Graduate Students of Jiangxi Province (No. YC2013-S027)the Hong Kong Scholars Program (No. XJ2012025)the China Post-doctoral Science Foundation funded project (No. 2012T50594, 2014M551866)the Jiangxi Post-doctoral Science Foundation (No. 2014KY11)Doctoral Fund of Ministry of Education of China (No. 20113601110008)
文摘The microstructure and mechanical properties of Mg–6Zn–1Y and Mg–6Zn–3Y（wt%） alloys under different cooling rates were investigated. The results show that the second dendrite arm spacing（SDAS） of Mg–6Zn–1Y and Mg–6Zn–3Y is reduced by 32 and 30% with increasing cooling rates（Rc） from 10.2 to 23 K/s, which can be predicted using a empirical model of SDAS=68 R 0：45：45cand SDAS=73 R 0c, respectively. The compressive strength of both alloys increases with increasing the cooling rate, which is attributed to the increase of volume fraction（Vf） of secondary phases under high cooling rate. The interaction of the cooling rate and component with SDAS has been theoretically analyzed using interdependence theory.
