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	The braking index of PSR B0540-69 and the associated pulsar wind nebula emission after spin-down rate transition 期刊论文 OAI收割 Monthly Notices of the Royal Astronomical Society, 2020, 卷号: 494, 页码: 1865-1870 作者: HXMT \| 收藏 \| 浏览/下载：54/0 \| 提交时间：2022/02/08 stars: magnetic field stars: neutron pulsars: general Astrophysics - High Energy Astrophysical Phenomena Abstract: In 2011 December, PSR B054-69 experienced a spin-down rate transition (SRT), after which the spin-down power of the pulsar increased by $\sim 36{{\ \rm per\ cent}}$. About 1000 d after the SRT, the X-ray luminosity of the associated pulsar wind nebula (PWN) was found to brighten by $32\pm 8{{\ \rm per\ cent}}$. After the SRT, the braking index n of PSR B0540-69 changes from n = 2.12 to 0.03 and then keeps this value for about five years before rising to n = 0.9 in the following years. We find that most of the current models have difficulties in explaining the measured braking index. One exceptive model of the braking index evolution is the increasing dipole magnetic field of PSR B0540-69. We suggest that the field increase may result from some instabilities within the pulsar core that enhance the poloidal component at the price of toroidal component of the magnetic field. The increasing dipole magnetic field will result in the X-ray brightening of the PWN. We fit the PWN X-ray light curve by two models: one assumes a constant magnetic field within the PWN during the brightening and the other assumes an enhanced magnetic field proportional to the energy density of the PWN. It appears that the two models fit the data well, though the later model seems to fit the data a bit better. This provides marginal observational evidence that magnetic field in the PWN is generated by the termination shock. Future high-quality and high-cadence data are required to draw a solid conclusion.
	Responses of Photosystem I Compared with Photosystem II to Fluctuating Light in the Shade-Establishing Tropical Tree Species Psychotria henryi 期刊论文 OAI收割 FRONTIERS IN PLANT SCIENCE, 2016, 卷号: 7 作者: Huang, Wei; Yang, Ying-Jie; Hu, Hong; Zhang, Shi-Bao 收藏 \| 浏览/下载：32/0 \| 提交时间：2017/01/05 constant high light fluctuating light PSI photoinhibition excess excitation energy shade-establishing species
	Responses of Photosystem I Compared with Photosystem II to Fluctuating Light in the Shade-Establishing Tropical Tree Species Psychotria henryi 期刊论文 OAI收割 FRONTIERS IN PLANT SCIENCE, 2016, 卷号: 7, 期号: x, 页码: 1549 Huang, Wei; Yang, Ying-Jie; Hu, Hong; Zhang,Shi-Bao 收藏 \| 浏览/下载：23/0 \| 提交时间：2016/11/17 constant high light fluctuating light PSI photoinhibition excess excitation energy shade-establishing species
	Design of programmable near infrared cold light source (EI CONFERENCE) 会议论文 OAI收割 2011 International Conference on Electronics and Optoelectronics, ICEOE 2011, July 29, 2011 - July 31, 2011, Dalian, China 作者: Fu Q.; Wang B.; Wang B.; Wang R. 收藏 \| 浏览/下载：30/0 \| 提交时间：2013/03/25 In the near infrared spectroscopy detector of Charge-coupled Device requires very high stability for light source. We design the cold light source in the measurement of near infrared spectroscopy. Cold light source consists of high-power op amp OPA549 high current constant current source and proportion integral differential (PID) control algorithm. As is shown in the experimental results the method is better the overshoot is very small the stability is excellent in the process of soft-start. While light intensity was able to meet the requirements of near-infrared instruments to measure. 2011 IEEE.