脉翅目螳蛉科昆虫化石记录较为丰富,在中生代以绝灭亚科Mesomantispinae和Doratomantispinae的属种最多,其中中螳蛉亚科Mesomantispinae分布时代更早,集中于中侏罗世至早白垩世.本文记述了采集自我国辽宁省北票市黄半吉沟下白垩统义县...脉翅目螳蛉科昆虫化石记录较为丰富,在中生代以绝灭亚科Mesomantispinae和Doratomantispinae的属种最多,其中中螳蛉亚科Mesomantispinae分布时代更早,集中于中侏罗世至早白垩世.本文记述了采集自我国辽宁省北票市黄半吉沟下白垩统义县组地层的螳蛉科中螳蛉亚科一新属新种,孙氏逸仙蛉Yatsenia suni gen. et sp. nov.该新属种与同亚科其他属在前翅脉序和翅斑上具显著差异,包括Sc与R1融合于近翅中部, CuP双分叉, 1A栉状分叉等特征,揭示了白垩纪螳蛉更为丰富的形态与物种多样性.展开更多
Achieving a high color rendering index(CRI)and luminous stability in single-structured Ce:Y_(3)Al_(5)O_(12)(Ce:YAG)phosphor ceramics(PCs)is crucial for high-power white light-emitting diodes or laser diodes(LEDs/LDs)....Achieving a high color rendering index(CRI)and luminous stability in single-structured Ce:Y_(3)Al_(5)O_(12)(Ce:YAG)phosphor ceramics(PCs)is crucial for high-power white light-emitting diodes or laser diodes(LEDs/LDs).However,cyan valleys and insufficient amounts of the red component in the Ce:YAG emission spectra significantly limit their real applications.In this work,a series of Ce,Mn:Y_(3)(Al,Sc)_(2)Al_(3)O_(12)(Ce,Mn:YSAG)PCs were fabricated by vacuum sintering,and efficient spectral regulation was realized for full-color lighting.The cyan valley was filled by the blueshifted emission peak of Ce^(3+)via Sc^(3+)doping.The orange‒red emission at approximately 580 nm was effectively supplemented via Mn^(2+)doping.In particular,CRI of Ce,Mn:YSAG increased from 56.4 to 85.8,a 52%increase compared with that of Ce:YAG under high-power LED excitation,and the operating temperature was stable at approximately 50℃for long working time.Moreover,CRI of 80.9 could still be obtained for PC-based white LDs.These results indicated that Ce,Mn:YSAG PC,which has excellent CRI and luminous stability,is an extremely promising color convertor for high-power white LEDs/LDs.展开更多
Topological insulators represent a new quantum phase of matter with spin-polarized surface states that are protected from backscattering, exhibiting electronic responses to light, such as topological quantum phase tra...Topological insulators represent a new quantum phase of matter with spin-polarized surface states that are protected from backscattering, exhibiting electronic responses to light, such as topological quantum phase transitions. However, the effects of high-frequency driving topological intrinsic systems have remained largely unexplored challenges experimentally for high-sensitivity terahertz detection. In this study, by integrating Sb2Te3 topological insulators with subwavelength metal antennas through micro-nano processing, a high-frequency terahertz detector with high sensitivity is proposed. The enhanced response originates from the asymmetric scattering of the surface electrons in the Sb_(2)Te_(3) flakes induced by the terahertz wave. The device displays room-temperature photodetection with a responsivity of 192 mA/W and equivalent noise power of less than 0.35 nW/Hz^(1/2) in the frequency range from 0.02 to 0.3 THz. These results pave the way for the exploitation of topological insulators for high-frequency operation in real-time imaging within long-wavelength optoelectronics.展开更多
文摘脉翅目螳蛉科昆虫化石记录较为丰富,在中生代以绝灭亚科Mesomantispinae和Doratomantispinae的属种最多,其中中螳蛉亚科Mesomantispinae分布时代更早,集中于中侏罗世至早白垩世.本文记述了采集自我国辽宁省北票市黄半吉沟下白垩统义县组地层的螳蛉科中螳蛉亚科一新属新种,孙氏逸仙蛉Yatsenia suni gen. et sp. nov.该新属种与同亚科其他属在前翅脉序和翅斑上具显著差异,包括Sc与R1融合于近翅中部, CuP双分叉, 1A栉状分叉等特征,揭示了白垩纪螳蛉更为丰富的形态与物种多样性.
基金financially supported by the National Key R&D Program of China(No.2021YFB3501700)the National Natural Science Foundation of China(Nos.52202135,61975070,and 52302141)+4 种基金the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD),the International S&T Cooperation Program of Jiangsu Province(No.BZ2023007)the Key R&D Project of Jiangsu Province(Nos.BE2023050 and BE2021040)Natural Science Foundation of Jiangsu Province(No.BK20221226)the Special Project for Technology Innovation of Xuzhou City(Nos.KC23380,KC21379,KC22461,and KC22497)the Open Project of State Key Laboratory of Crystal Materials(No.KF2205).
文摘Achieving a high color rendering index(CRI)and luminous stability in single-structured Ce:Y_(3)Al_(5)O_(12)(Ce:YAG)phosphor ceramics(PCs)is crucial for high-power white light-emitting diodes or laser diodes(LEDs/LDs).However,cyan valleys and insufficient amounts of the red component in the Ce:YAG emission spectra significantly limit their real applications.In this work,a series of Ce,Mn:Y_(3)(Al,Sc)_(2)Al_(3)O_(12)(Ce,Mn:YSAG)PCs were fabricated by vacuum sintering,and efficient spectral regulation was realized for full-color lighting.The cyan valley was filled by the blueshifted emission peak of Ce^(3+)via Sc^(3+)doping.The orange‒red emission at approximately 580 nm was effectively supplemented via Mn^(2+)doping.In particular,CRI of Ce,Mn:YSAG increased from 56.4 to 85.8,a 52%increase compared with that of Ce:YAG under high-power LED excitation,and the operating temperature was stable at approximately 50℃for long working time.Moreover,CRI of 80.9 could still be obtained for PC-based white LDs.These results indicated that Ce,Mn:YSAG PC,which has excellent CRI and luminous stability,is an extremely promising color convertor for high-power white LEDs/LDs.
基金Shanghai Municipal Science and Technology Major Project(2019SHZDZX01)Science and Technology Commission of Shanghai Municipality(20JC1416000,20QA1410400,22JC1402900)+3 种基金Excellent Postdoctoral Research Projects of Zhejiang Province(ZJ2021019)Natural Science Foundation of Zhejiang Province(LQ20F050005,LR22F050004)National Natural Science Foundation of China(62222514,61521005,61875217,61875218,61875223,61991442,62005249,91850208)State Key Program for Basic Research of China(2018YFA0306200).
文摘Topological insulators represent a new quantum phase of matter with spin-polarized surface states that are protected from backscattering, exhibiting electronic responses to light, such as topological quantum phase transitions. However, the effects of high-frequency driving topological intrinsic systems have remained largely unexplored challenges experimentally for high-sensitivity terahertz detection. In this study, by integrating Sb2Te3 topological insulators with subwavelength metal antennas through micro-nano processing, a high-frequency terahertz detector with high sensitivity is proposed. The enhanced response originates from the asymmetric scattering of the surface electrons in the Sb_(2)Te_(3) flakes induced by the terahertz wave. The device displays room-temperature photodetection with a responsivity of 192 mA/W and equivalent noise power of less than 0.35 nW/Hz^(1/2) in the frequency range from 0.02 to 0.3 THz. These results pave the way for the exploitation of topological insulators for high-frequency operation in real-time imaging within long-wavelength optoelectronics.
