Thermal aging effects on surface of 2.5 Me V Fe ion-irradiated Fe–0.6%Cu alloy were investigated using positron annihilation techniques. The samples were irradiated at 573 K to a dose of 0.1 dpa. Their thermal aging ...Thermal aging effects on surface of 2.5 Me V Fe ion-irradiated Fe–0.6%Cu alloy were investigated using positron annihilation techniques. The samples were irradiated at 573 K to a dose of 0.1 dpa. Their thermal aging was performed at 573 K for 5, 50 and 100 h. From the results of Doppler broadening measurement, an obvious trough could be seen in near-surface region from the S parameters and inflection point form at S–W curves. This indicates changes in the annihilation mechanism of positrons in surface region after thermal aging. Coincident Doppler broadening indicates that the density of Cu precipitates in the thermal aged samples decreased, due to recovery of the vacancies.展开更多
The Cretaceous bird trackway originally labeled Aquatilavipes anhuiensis, in 1994, had previously been examined, photographed and replicated, but never described or illustrated in detail. However, it has been part of ...The Cretaceous bird trackway originally labeled Aquatilavipes anhuiensis, in 1994, had previously been examined, photographed and replicated, but never described or illustrated in detail. However, it has been part of a widening discussion about the distribution of Aquatilavipes and Koreanaornis in China(and Korea). Here we illustrate and formally describe the holotype in detail and assign it to Koreanaornis(Koreanaornis anhuiensis) as informally proposed by previous authors. We also demonstrate that most authenticated reports of Koreanaornis, including the Anhui occurrence, are from the Lower Cretaceous, not from the Upper Cretaceous as previously reported.展开更多
While materials science research in the rechargeable battery field is usually application-oriented,the general supercooled liquid theory from glass science can drive high-performance low-temperature aqueous batteries,...While materials science research in the rechargeable battery field is usually application-oriented,the general supercooled liquid theory from glass science can drive high-performance low-temperature aqueous batteries,facilitating cross-disciplinary collaborations and simultaneous research breakthroughs.展开更多
The ability to widely tune the optical properties of amorphous alloys is highly desirable especially for their potential applications in optoelectronic devices.In this work,we demonstrate that introducing oxygen into ...The ability to widely tune the optical properties of amorphous alloys is highly desirable especially for their potential applications in optoelectronic devices.In this work,we demonstrate that introducing oxygen into an amorphous alloy system of Co-Fe-Ta-B enables the formation of various amorphous derivatives ranging from metals to semiconductors,and eventually to insulators.These oxygencontaining amorphous derivatives gradually become transparent with the opened bandgaps,leading to a continuous increase in their optical transmittance.Furthermore,the reflective metal-type amorphous alloy and transparent insulator-type amorphous oxide of the system can be integrated together to realize the full-color tuning over the entire visible spectral range.This provides a new way to develop large-area color coatings with high design flexibility and full-color tunability.We envisage that the design concept proposed in this work is also applicable to many other amorphous alloy systems,from which all types of amorphous materials including alloys,semiconductors and insulators may be developed to show unprecedented optical functionalities.展开更多
基金supported by the National Natural Science Foundation of China(Nos.91026006,91226103,11475193,11475197,11575205and 11505192)Beijing Natural Science Foundation(No.1164017)
文摘Thermal aging effects on surface of 2.5 Me V Fe ion-irradiated Fe–0.6%Cu alloy were investigated using positron annihilation techniques. The samples were irradiated at 573 K to a dose of 0.1 dpa. Their thermal aging was performed at 573 K for 5, 50 and 100 h. From the results of Doppler broadening measurement, an obvious trough could be seen in near-surface region from the S parameters and inflection point form at S–W curves. This indicates changes in the annihilation mechanism of positrons in surface region after thermal aging. Coincident Doppler broadening indicates that the density of Cu precipitates in the thermal aged samples decreased, due to recovery of the vacancies.
基金support of grant number 11791012 issued to Dr. Masaki Masukawa from Tokyo Gakugei University, Japansupported by the National Natural Science Foundation of China (Grant No. 41772008)+1 种基金the State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences (Grant No.173127)the Special Scientific Research Fund of the Non-Profit Sector Project, Ministry of Land and Resources of China (Grant No.201511054)
文摘The Cretaceous bird trackway originally labeled Aquatilavipes anhuiensis, in 1994, had previously been examined, photographed and replicated, but never described or illustrated in detail. However, it has been part of a widening discussion about the distribution of Aquatilavipes and Koreanaornis in China(and Korea). Here we illustrate and formally describe the holotype in detail and assign it to Koreanaornis(Koreanaornis anhuiensis) as informally proposed by previous authors. We also demonstrate that most authenticated reports of Koreanaornis, including the Anhui occurrence, are from the Lower Cretaceous, not from the Upper Cretaceous as previously reported.
基金support from the National Natural Science Foundation of China(Grant No.52471178).
文摘While materials science research in the rechargeable battery field is usually application-oriented,the general supercooled liquid theory from glass science can drive high-performance low-temperature aqueous batteries,facilitating cross-disciplinary collaborations and simultaneous research breakthroughs.
基金financially supported by the National Science Fund for Excellent Young Scholars (51922053)the School of Materials Science and Engineering at Tsinghua Universitythe funding from the National Key Research and Development Program (2016YFB0700402)+2 种基金the National Natural Science Foundation of China (51822105 and 11834009)the City University of Hong Kong (9610484)the Shenzhen Research Institute, the City University of Hong Kong
文摘The ability to widely tune the optical properties of amorphous alloys is highly desirable especially for their potential applications in optoelectronic devices.In this work,we demonstrate that introducing oxygen into an amorphous alloy system of Co-Fe-Ta-B enables the formation of various amorphous derivatives ranging from metals to semiconductors,and eventually to insulators.These oxygencontaining amorphous derivatives gradually become transparent with the opened bandgaps,leading to a continuous increase in their optical transmittance.Furthermore,the reflective metal-type amorphous alloy and transparent insulator-type amorphous oxide of the system can be integrated together to realize the full-color tuning over the entire visible spectral range.This provides a new way to develop large-area color coatings with high design flexibility and full-color tunability.We envisage that the design concept proposed in this work is also applicable to many other amorphous alloy systems,from which all types of amorphous materials including alloys,semiconductors and insulators may be developed to show unprecedented optical functionalities.
