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	Ultra-wide Bandwidth Observations of 19 Pulsars with Parkes Telescope 期刊论文 OAI收割 Research in Astronomy and Astrophysics, 2022, 卷号: 22, 期号: 8, 页码: 85001 作者: Zhou, Zu-Rong; Wang, Jing-Bo; Wang, Na; Hobbs, George; Wang, Shuang-Qiang \| 收藏 \| 浏览/下载：22/0 \| 提交时间：2023/06/19 (stars:) pulsars: general stars: neutron methods: data analysis flux-density measurements polarization discovery spectra polarimetry profiles emission Astronomy & Astrophysics
	Effect of dissolved organic matter and its fractions on disinfection by-products formation upon karst surface water 期刊论文 OAI收割 Chemosphere, 2022, 卷号: 308, 页码: 136324 作者: Hui Zhou; Liye Tian; Maofei Ni; Sixi Zhu; Runyu Zhang \| 收藏 \| 浏览/下载：32/0 \| 提交时间：2023/03/30 Dissolved Organic Matter Karst Water Disinfection By-products Formation Spectra Analysis Chemical Characteristics
	三维荧光光谱在中药当归、大黄质量分析中的应用学位论文 OAI收割北京: 中国科学院大学, 2021 作者: 郭晴茹 \| 收藏 \| 浏览/下载：100/0 \| 提交时间：2023/01/19 三维荧光光谱,质量分析,模式识别,当归,大黄 Three-dimensional fluorescence spectra, Quality Analysis, Pattern recogniti, Angelica, Rhubarb
	Rare Object Search From Low-S/N Stellar Spectra in SDSS 期刊论文 OAI收割 IEEE ACCESS, 2020, 卷号: 8, 页码: 66475-66488 作者: Wu, Minglei; Pan, Jingchang; Yi, Zhenping; Wei, Peng \| 收藏 \| 浏览/下载：19/0 \| 提交时间：2021/12/06 Principal component analysis Search problems Astronomy Support vector machines Wavelength division multiplexing Feature extraction Random forests SDSS stellar spectra machine learning rare object search
	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：64/0 \| 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.
	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 \| 收藏 \| 浏览/下载：59/0 \| 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.
	Underdetermined blind separation of three-way fluorescence spectra of PAHs in water 期刊论文 OAI收割 SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY, 2018, 卷号: 199, 期号: 无, 页码: 80-85 作者: Yang, Ruifang; Zhao, Nanjing; Xiao, Xue; Zhu, Wei; Chen, Yunan \| 收藏 \| 浏览/下载：21/0 \| 提交时间：2019/08/23 Polycyclic aromatic hydrocarbons Three-way fluorescence spectra Sparse component analysis Component recognition
	Feasibility of coupling a thermal/optical carbonanalyzer to a quadrupole mass spectrometer forenhanced PM2.5 speciation 期刊论文 OAI收割 Journal of the Air & Waste Management Association, 2018, 卷号: 68, 期号: 5, 页码: 463-476 作者: Gustavo M. Riggio; Chow, Judith C; Cropper,Paul M \| 收藏 \| 浏览/下载：34/0 \| 提交时间：2018/09/29 Pm2.5 Speciatiopn Material Balance Thermal Analysis Quartz-fiber Mass Spectra
	Calcium deficiency in hydroxyapatite and its drug delivery applications 期刊论文 OAI收割 MICRO & NANO LETTERS, 2018, 卷号: 13, 期号: 4, 页码: 562-564 作者: Rajagopalan, Vijayaraghavan; Koppala, Sivasankar; Swamiappan, Sasikumar; Gangarajula, Yuvaraj; Xu, Lei \| 收藏 \| 浏览/下载：50/0 \| 提交时间：2019/06/20 Calcium Compounds Bioceramics Drug Delivery Systems Drugs Nanoparticles Particle Size Nanofabrication Nanomedicine Fourier Transform Infrared Spectra Precipitation Calcination X-ray Diffraction Scanning Electron Microscopy X-ray Chemical Analysis Nanoporous Materials Porosity Drug Delivery Applications Calcium Deficient Hydroxyapatites Precipitation Method Calcined Samples Fourier Transformation Infrared Spectroscopy Powder X-ray Diffraction Scanning Electron Microscopy Energy-dispersive X-ray Spectroscopy Phase Purity Particle Size Particle Shape Hap Structure Ciprofloxacin Sustained Drug Release Phosphate Buffer Solution Porous Structure [Ca10-x(Po4)(6)(Oh)(2)]