Agency Fluctuations and Identity Transformations in Chinese English-Majors on Their Learning Trajectories

This paper explores agency fluctuations and identity transformations in Chinese English-majors and how they are related to the process of English learning. By tracing a group of students for four years in a Chinese university and conducting qualitative analyses to their oral narrations of learning experiences at different periods, the study has found that most participants started and ended their university life at relatively high levels of agency, with inevitable ups and downs in between. Agency fluctuations in the learners are the result of their identity positioning and repositioning within a complex and ever-changing context. Concordant or conflicting identities may co-exist within an individual learner and keep changing across different situations. Learner identities will cause increase or reduction in their investment in English learning, while their learning experience will in turn reinforce or undermine their identities. The study sheds light on the intricate relationships between agency, identity and language learning and therefore has important implications for English learning and teaching in China.

Broadening and enhancing emission of Cr^(3+) simultaneously by co-doping Yb^(3+) in Ga1.4ln0.6SnO5

Cr^(3+)doped broadband near-infrared(NIR) emitting phosphors are currently the focus of research.Researchers have developed a variety of strategies to achieve broad and strong NIR emission,However,it is a conundrum to simultaneously broaden and enhance the emission of Cr^(3+)with a single strategy,In this work,we solved this problem by co-doping Yb^(3+).Under 452 nm excitation,Ga_(1.4)In_(0.6)SnO_(5)(GISO):0.01Cr^(3+)shows ultrabroadband NIR emission covering 650-1300 nm with a peak of 884 nm,The full width half maximum(FWHM) of the emission is 215 nm and the internal quantum yield(IQY) is 25%.This indicates that the double sites occupation strategy is favorable to achieve ultra-broadband NIR emission.The co-doping of Yb^(3+)can effectively broaden and enhance the emission of Cr^(3+).The FWHM for GISO:0.01Cr^(3+),0.002Yb^(3+)extends to 245 nm,and the IQY increases to 28%.Further increasing the concentration of Yb^(3+)to 0.005,the IQY is lifted to 32%.Finally,a phosphor-co nverted light emitting diode(pc-LED) was prepared by integrating the GISO:0.01Cr^(3+),0.002Yb^(3+)with a blue light chip.Under the current drive of 40 mA,the maximum output power of pc-LED is 4.54 mW,and the photoelectric conversion efficiency is 4.12%.These results indicate that Yb^(3+)ions can simultaneously broaden the emission band and improve the emission efficiency.This work provides an effective strategy for the design of efficient broadband NIR phosphors in the future.