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Synchronous X-ray/Optical QPOs from the Black Hole LMXB MAXI J1820+070 期刊论文 OAI收割
Monthly Notices of the Royal Astronomical Society, 2021
作者: HXMT

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收藏 | 浏览/下载：53/0 | 提交时间：2022/02/08

black hole physics Low Mass X-ray Binaries accretion accretion discs stars: individual (MAXI J1820+070) Astrophysics - High Energy Astrophysical Phenomena Abstract: We present high-speed optical photometry from SAAO and SALT on the black hole LMXB MAXI J1820+070 (ASSASN-18ey), some of it simultaneous with NICER, Swift and Insight-HXMT X-ray coverage. We detect optical Quasi-Periodic Oscillations (QPOs) that move to higher frequencies as the outburst progresses, tracking both the frequency and evolution of similar X-ray QPOs previously reported. Correlated X-ray/optical data reveal a complex pattern of lags, including an anti-correlation and a sub-second lag that evolve over the first few weeks of outburst. They also show correlated components separated by a lag equal to the QPO period roughly centered on zero lag, implying that the inter-band variability is strongly and consistently affected by these QPOs at a constant phase lag of roughly ±Ю The synchronisation of X-ray and optical QPOs indicates that they must be produced in regions physically very close to each other we thus propose that they can be explained by a precessing jet model, based on analogies with V404 Cyg and MAXI J1348-630.

Magnetic softness, dynamic magnetization, and relaxation behavior of FeSiBC amorphous alloys 期刊论文 OAI收割
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS, 2020, 卷号: 31, 期号: 5, 页码: 4261-4270
作者: He, Aina; Xiao, Huiyun; Dong, Yaqiang; Wang, Anding

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收藏 | 浏览/下载：38/0 | 提交时间：2020/12/16

CORE LOSS COMPLEX PERMEABILITY HIGH-FREQUENCY FE TEMPERATURE COERCIVITY SI PHASE

Numerical study of comb-based high-accuracy distance measurement utilizing VIPA interferometry 期刊论文 OAI收割
Journal of Optics, 2019, 卷号: 21, 期号: 2, 页码: 105645.R1-1-9
作者: Zhu XM(朱小明); He JP(何晋平)

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收藏 | 浏览/下载：27/0 | 提交时间：2020/02/03

Ultra-high resolution spectroscopy Ultra-high precision distance measurement Laser frequency comb Virtually imaged phase array interferometry

Timing analysis of Swift J1658.2-4242's outburst in 2018 with Insight-HXMT, NICER and AstroSat 期刊论文 OAI收割
Journal of High Energy Astrophysics, 2019, 卷号: 24, 页码: 30-40
作者: HXMT

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收藏 | 浏览/下载：57/0 | 提交时间：2022/02/08

Accretion accretion disks Black hole physics X-rays: binaries: Swift J1658.2-4242 Astrophysics - High Energy Astrophysical Phenomena Abstract: We present the observational results from a detailed timing analysis of the black hole candidate Swift J1658.2-4242 during its 2018 outburst with the observations of Hard X-ray Modulation Telescope (Insight-HXMT), Neutron Star Interior Composition Explorer (NICER) and AstroSat in 0.1-250 keV. The evolution of intensity, hardness and integrated fractional root mean square (rms) observed by Insight-HXMT and NICER are presented in this paper. Type-C quasi-periodic oscillations (QPOs) observed by NICER (0.8-3.5 Hz) and Insight-HXMT (1-1.6 Hz) are also reported in this work. The features of the QPOs are analyzed with an energy range of 0.5-50 keV. The relations between QPO frequency and other characteristics such as intensity, hardness and QPO rms are carefully studied. The timing and spectral properties indicate that Swift J1658.2-4242 is a black hole binary system. Besides, the rms spectra of the source calculated from the simultaneous observation of Insight-HXMT, NICER and AstroSat support the Lense-Thirring origin of the QPOs. The relation between QPO phase lag and the centroid frequency of Swift J1658.2-4242 reveals a near zero constant when < 4Hz and a soft phase lag at 6.68 Hz. This independence follows the same trend as the high inclination galactic black hole binaries such as MAXI J1659-152.

Engineering quadratic nonlinear photonic crystals for frequency conversion of lasers 期刊论文 iSwitch采集
Journal of optics, 2018, 卷号: 20, 期号: 3
作者: Chen,Baoqin; Hong,Lihong; Hu,Chenyang; Zhang,Chao; Liu,Rongjuan

收藏 | 浏览/下载：69/0 | 提交时间：2019/05/09

Quasi-phase matching Optical frequency conversion Nonlinear photonic crystals Second harmonic generation High-harmonic generation

High frequency forcing on nonlinear systems 期刊论文 OAI收割
CHINESE PHYSICS B, 2013, 卷号: 22, 期号: 3
作者: Yao Cheng-Gui; He Zhi-Wei; Zhan Meng

收藏 | 浏览/下载：26/0 | 提交时间：2015/06/23

high frequency nonlinear oscillator inertial approximation phase transitions

Lightweight design of large scale theodolite's turntable based on topology optimization of continuum structure (EI CONFERENCE) 会议论文 OAI收割
2012 International Conference on Optoelectronics and Microelectronics, ICOM 2012, August 23, 2012 - August 25, 2012, Changchun, China
作者: Wang Y.; Wang Y.; Wang Y.; Wang Y.; Wang Y.

收藏 | 浏览/下载：29/0 | 提交时间：2013/03/25

In order to solve the problem that the weight of large scale theodolite's casting or steel plate welded structure is too heavy lightweight design of large scale turntable based on topology optimization of continuum structure is investigated. Topology optimization could have better optimization efficiency because it can provide the optimized distribution of material and gain optimized structure in conceptual design phase of the structural design. In order to obtain lightweight and high stiffness structure a truss turntable based on topology optimization of continuum structure is presented and the validity of this lightweight structure is examined by finite element analysis. Comparing to the traditional welding steel turntable the lightweight turntable without changing the static displacement can lose 386.48 kg(lightweight ratio is 26.7%) and its first-order natural frequency raises from 167.02Hz to 173.71Hz. Meanwhile in other aspects this turntable also has better performance than traditional structure. 2012 IEEE.

Research on satellite platform vibration compensation technology for space optical communication (EI CONFERENCE) 会议论文 OAI收割
2012 International Meeting on Opto-Electronics Engineering and Materials Research, OEMR 2012, July 27, 2012 - July 29, 2012, Shenyang, Liaoning, China
Han C.; Li X.

收藏 | 浏览/下载：23/0 | 提交时间：2013/03/25

The piezo-electric steering control system is used to compensate the vibration of satellite platform. The mathematical model of piezo-electric steering system is built. The adaptive controller based on improved LMS filter algorithm is designed according to this system characteristic. The adaptive delay filter is designed to solve slow convergence speed problem of traditional algorithm. Meanwhile the adaptive delay filter can also compensate phase delay of control circuit. The adaptive deviation filter is introduced and it effectively compensates the vibration deviation which is low frequency and high amplitude. The experimental results show that the remained errors are rad which meets space optical communication requirement and proves that this control scheme is valid and feasible. (2012) Trans Tech Publications Switzerland.

Effect of annealing on the microstructure and mechanical properties of polypropylene with oriented shish-kebab structure 期刊论文 OAI收割
polymer international, 2012, 卷号: 61, 期号: 2, 页码: 252-258
Bai HW; Deng H; Zhang Q; Wang K; Fu Q; Zhang ZJ; Men YF

收藏 | 浏览/下载：20/0 | 提交时间：2013/06/08

HIGH-DENSITY POLYETHYLENE FLOW-INDUCED CRYSTALLIZATION INJECTION-MOLDED BARS ISOTACTIC POLYPROPYLENE PHASE-COMPOSITION MOLECULAR-ORIENTATION PROCESSING CONDITIONS RELAXATION PROCESSES NUCLEATING-AGENT LOW-FREQUENCY

Imaging system effects on the measuring accuracy of the optical surface in interferometer (EI CONFERENCE) 会议论文 OAI收割
3rd International Conference on Measuring Technology and Mechatronics Automation, ICMTMA 2011, January 6, 2011 - January 7, 2011, Shanghai, China
Yang W.; Liu M.; Xu W.

收藏 | 浏览/下载：27/0 | 提交时间：2013/03/25

In order to measure high accuracy or mid spatial frequency optical surfaces this study investigated imaging system in Fizeau interferometer. Interferometer is a transferring phase information system. General transfer function can't evaluate the ability of imaging system in interferometer that transfers the phase information of the optical surface. So this paper deduced instrument transfer function (ITF) and used ITF to evaluate the phase information transfer ability of interferometer. We obtained some results about ITF of imaging system by numerical simulation when there are different aberrations in imaging system or measuring optical surfaces were different. Our results indicate that ITF can evaluate the ability of transferring phase information in interferometer and the distortion of imaging system evidently affects the accuracy of interferometric measurements. 2010 IEEE.