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	An underlying clock in the extreme flip-flop state transitions of the black hole transient Swift J1658.2-4242 期刊论文 OAI收割 Astronomy and Astrophysics, 2020, 卷号: 641, 页码: A101 作者: HXMT \| 收藏 \| 浏览/下载：60/0 \| 提交时间：2022/02/08 accretion accretion disks black hole physics X-rays: binaries time Astrophysics - High Energy Astrophysical Phenomena Abstract: Aims: Flip-flops are top-hat-like X-ray flux variations, which have been observed in some transient accreting black hole binary systems, and feature simultaneous changes in the spectral hardness and the power density spectrum (PDS). They occur at a crucial time in the evolution of these systems, when the accretion disc emission starts to dominate over coronal emission. Flip-flops remain a poorly understood phenomenon, so we aim to thoroughly investigate them in a system featuring several such transitions. Methods: Within the multitude of observations of Swift J1658.2-4242 during its outburst in early 2018, we detected 15 flip-flops, enabling a detailed analysis of their individual properties and the differences between them. We present observations by XMM-Newton, NuSTAR, Astrosat, Swift, Insight-HXMT, INTEGRAL, and ATCA. We analysed their light curves, searched for periodicities, computed their PDSs, and fitted their X-ray spectra, to investigate the source behaviour during flip-flop transitions and how the interval featuring flip-flops differs from the rest of the outburst. Results: The flip-flops of Swift J1658.2-4242 are of an extreme variety, exhibiting flux differences of up to 77% within 100 s, which is much larger than what has been seen previously. We observed radical changes in the PDS simultaneous with the sharp flux variations, featuring transitions between the quasi-periodic oscillation types C and A, which have never been observed before. Changes in the PDS are delayed, but more rapid than changes in the light curve. Flip-flops occur in two intervals within the outburst, separated by about two weeks in which these phenomena were not seen. Transitions between the two flip-flop states occurred at random integer multiples of a fundamental period of 2.761 ks in the first interval and 2.61 ks in the second. Spectral analysis reveals the high and low flux flip-flop states to be very similar, but distinct from intervals lacking flip-flops. A change of the inner temperature of the accretion disc is responsible for most of the flux difference in the flip-flops. We also highlight the importance of correcting for the influence of the dust scattering halo on the X-ray spectra.
	黄海桑沟湾水体及沉积物中微塑料污染特征研究期刊论文 OAI收割海洋环境科学, 2019, 卷号: 38, 期号: 2, 页码: 198-204 作者: 熊宽旭; 赵新月; 周倩; 付传城; 涂晨 \| 收藏 \| 浏览/下载：40/0 \| 提交时间：2020/06/17 桑沟湾微塑料潮滩丰度空间分布 Sanggou bay microplastics tidal flats abundance spatial distribution In recent years,research on microplastics pollution in the marine environment has been increasing,but studies on microplastics in water bodies and sediments of the bay under the influence of high-intensity human activities are still rarely reported. In this study,the pollution characteristics of microplastics in the wayer and sediments of Sanggou bay were investigated in December 2017,after the harvest of large-scale aquaculture,with the aim to study the effects of aquaculture activities and hydrodynamics on pollution characteristics and spatial distribution of microplastics in the bay. The results showed that the types of microplastics in the water and sediments of Sanggou bay were mainly fibers,fragments,films,foams and particles. The microplastic abundances in the water and sediments were 1.8 ~ 31.2 N/L,31.2 ~ 1246.8 N/kg,respectively. The average particle sizes of microplastics in water and sediments were 0.51 0.20 mm and 1.54 1.02 mm,respectively. The results of spatial distribution of microplastics in Sanggou bay showed that the high abundance area mainly appears in the inshore waters,and the abundance of microplastics tends to decrease from the inner areas of estuary to the outshore areas. The heterogeneity of microplastic abundance and spatial distribution in Sanggou bay is mainly affected by human activities such as aquaculture,living and shipping,as well as hydrodynamics. In the future,fine sampling and analysis are needed to fully understand the temporal and spatial distribution of microplastics pollution in the bay areas.
	Theoretical studies of traditional and halogen-shared halogen bonds: the doped all-metal aromatic clusters MAl3 (-) (M = Si, Ge, Sn, Pb) as halogen bond acceptors 期刊论文 OAI收割 theoretical chemistry accounts, 2015, 卷号: 134, 期号: 12 作者: Cheng, Na; Liu, Yongjun; Zhang, Changqiao 收藏 \| 浏览/下载：20/0 \| 提交时间：2015/12/17 Halogen bonds Hydrogen bonds MP2 AIM analysis Aromatic clusters MAl3-
	Structures and hydrogen bonds of biodegradable naphthenate ionic liquids 期刊论文 OAI收割 FLUID PHASE EQUILIBRIA, 2013, 卷号: 360, 期号: 0, 页码: 169-179 作者: He, Hongyan; Zhang, Suojiang; Liu, Xiaomin; Wang, Jinquan; Yao, Xiaoqian 收藏 \| 浏览/下载：35/0 \| 提交时间：2015/05/05 Biodegradable ionic liquid Hydrogen bond Electronic properties NBO analysis AIM analysis
	The application of the discrete sliding mode control based on state observer in aerial camera (EI CONFERENCE) 会议论文 OAI收割 2nd Annual Conference on Electrical and Control Engineering, ICECE 2011, September 16, 2011 - September 18, 2011, Yichang, China 作者: Zhang X.; Zhang X.; Zhang X. 收藏 \| 浏览/下载：17/0 \| 提交时间：2013/03/25 A discrete sliding mode control scheme based on state observer is designed for DC torque motor. Aim on the problem of control chattering and steady-state chattering caused by discrete sliding mode control method adaptive reaching law is proposed Non-chattering and stability are made an analysis. The aerial camera is chosen as an experimental platform and the discrete sliding mode controller with adaptive reaching law is applied to the drawtube system the value of acceleration can be observed on line. The experiment results show the control scheme can effectively eliminate chattering and also make the drawtube system achieve better dynamical performance. 2011 IEEE.
	Study on dynamic imaging on TDI CCD optical remote sensor of push-broom technology (EI CONFERENCE) 会议论文 OAI收割 5th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Optical Test and Measurement Technology and Equipment, April 26, 2010 - April 29, 2010, Dalian, China 作者: Liu L.; Ren J.-Y.; Liu L.; Gao M.-H. 收藏 \| 浏览/下载：22/0 \| 提交时间：2013/03/25 A set special detecting system is proposed based on TDICCD push-broom technology applying in dynamic imaging detecting experiment of space optics remote sensor. In the system In the course of detecting push-broom movement of the satellite is simulated through using double supporting U structure precision rotary platform with remote sensor by angular speed 0.555/s regard Nyquist frequency target as detecting aim within the range of 5 and control precision on steady speed achieves 0.3% in order to solve matching uncertainty between the CCD pixel and the vertical target strip image when the remote sensor does push-broom make matching simplify enhance the measurement result the accuracy. So the tolerance a/n arithmetic progression gap target strip is joined in each group of rectangular vertical group target strip. The remote sensor obtains in vertical the level and 45 the direction 0 fields of view 0.86 the field of view Nyquist frequency target strip image after detected a group target strip which can precision matching to TDICCD pixel at least can be obtained through analysis and dealing with 0.86 field of view's target strip image. The experiment not only verifies the detecting system's feasibility but simultaneously verifies whether to have the high quality dynamic imaging quality when TDICCD push-broom technology is adopted on the remote sensor developed. 2010 Copyright SPIE - The International Society for Optical Engineering.
	Theoretical study of the N-H…O red-shifted and blue-shifted hydrogen bonds 期刊论文 OAI收割 Science in China. Series B: Chemistry, 2007, 卷号: 50 作者: YANG Yong; ZHANG WeiJun; PEI ShiXin; SHAO Jie; HUANG Wei \| 收藏 \| 浏览/下载：20/0 \| 提交时间：2020/11/23 red-shifted H-bond blue-shifted H-bond AIM topological analysis NBO analysis
	Support technique of ultra thin mirror in space optics (EI CONFERENCE) 会议论文 OAI收割 2nd International Symposium on Advanced Optical Manufacturing and Testing Technologies: Large Mirrors and Telescopes, November 2, 2005 - November 5, 2005, Xian, China 作者: Ren J.-Y.; Gao M.-H. 收藏 \| 浏览/下载：34/0 \| 提交时间：2013/03/25 With the development of space optical system the technique of ultra thin mirror come forth and is paid more attention because of less difficulty in machining low cost lightweight no disassembly during detecting and maintaining. The key technique takes advantage of deformation of ultra thin mirror as the influence of environment to adjust the surface figure. Its accuracy meets requirement. An analysis method is based on finite element analysis (FEA) and many items including the amount of support points the way of arrangement the optimum design of support component are studied. The finite element method was used to analyze the mirror and some different mirror support schemes. The principal aim of the mirror analysis is to get numbers of support points and the ways of the support. There are three schemes including 12-6-1 12-8-1 and 16-8-1 models. Deformation of deadweight is calculated under the three conditions. The way of 16-8-1 is more suitable than the designs of other two. The support subassembly is amended to meet with the mirror surface RMS in the range of 30m. Deformation of the mirror with support structure has been calculated. The result is 16.52nm lower than a quarter of the wavelength which indicates the feasibility of the support scheme applied to mirror. Theoretical result for the best way of support is presented. The result of analysis shows that requirement surface figure could be met through adjusting support points. It predicts feasibility of the support technique and provides theoretical value for active adjustment in the laboratory. At present support and adjusting experiment of ultra thin mirror is being carried on.
	A new algorithm of image segmentation for overlapping grain image (EI CONFERENCE) 会议论文 OAI收割 ICO20: Optical Information Processing, August 21, 2005 - August 26, 2005, Changchun, China 作者: Zhang X.; Zhang X.; Zhang X. 收藏 \| 浏览/下载：17/0 \| 提交时间：2013/03/25 Image segmentation is primary issue in image processing at the same time it is principal problem in low level vision in computer vision field. It is the key technology to process image analysis image comprehend and image depict successfully. Aim at measurement of granularity size of nonmetal grain a new algorithm of image segmentation and parameters calculation for overlapping grain image is studied. The hypostasis of this algorithm is present some new attributes of graph sequence from discrete attribute of graph consequently achieve that pick up the geometrical characteristics from input graph and new graph sequence which in favor of image segmentation is recombined. The conception that image edge denoted with "twin-point" is put forward base on geometrical characters of point image edge is transformed into serial edge and on recombined serial image edge based on direction vector definition of line and some additional restricted conditions the segmentation twin-points are searched with thus image segmentation is accomplished. Serial image edge is transformed into twin-point pattern to realize calculation of area and granularity size of nonmetal grain. The inkling and uncertainty on selection of structure element which base on mathematical morphology are avoided in this algorithm and image segmentation and parameters calculation are realized without changing grain's self statistical characters.