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	Constraining the X-Ray-Infrared Spectral Index of Second-timescale Flares from SGR 1935+2154 with Palomar Gattini-IR 期刊论文 OAI收割 The Astrophysical Journal, 2020, 卷号: 901, 页码: L7 作者: HXMT \| 收藏 \| 浏览/下载：24/0 \| 提交时间：2022/02/08 Radio transient sources Magnetars Soft gamma-ray repeaters 2008 992 1471 Astrophysics - High Energy Astrophysical Phenomena Astrophysics - Instrumentation and Methods for Astrophysics Abstract: The Galactic magnetar SGR 1935+2154 has been reported to produce the first example of a bright millisecond-duration radio burst (FRB 200428) similar to the cosmological population of fast radio bursts (FRBs). The detection of a coincident bright X-ray burst represents the first observed multiwavelength counterpart of an FRB. However, the search for similar emission at optical wavelengths has been hampered by the high inferred extinction on the line of sight. Here, we present results from the first search for second-timescale emission from the source at near-infrared (NIR) wavelengths using the Palomar Gattini-IR observing system in the J band, enabled by a novel detector readout mode that allows short exposure times of ?0.84 s with 99.9% observing efficiency. With a total observing time of ?12 hr (?47,728 images) during its 2020 outburst, we place median 3Ҡlimits on the second-timescale NIR fluence of ?18 Jy ms (13.1 AB mag). The corresponding extinction-corrected limit is ?125 Jy ms for an estimated extinction of A_J = 2.0 mag. Our observations were sensitive enough to easily detect an NIR counterpart of FRB 200428 if the NIR emission falls on the same power law as observed across its radio to X-ray spectrum. We report nondetection limits from epochs of four simultaneous X-ray bursts detected by the Insight-HXMT and NuSTAR telescopes during our observations. These limits provide the most stringent constraints to date on fluence of flares at 10¹⁴ Hz, and constrain the fluence ratio of the NIR emission to coincident X-ray bursts to R_NIR ? 0.025 (fluence index ?0.35).
	高灵敏气相质谱仪的研制与应用学位论文 OAI收割博士, 北京: 中国科学院研究生院, 2016 作者: 孙万启收藏 \| 浏览/下载：153/0 \| 提交时间：2017/07/18 高灵敏质谱，单光子电离，挥发性有机物，二噁英，炸药和军事毒剂检测，痕量检测， High-sensitive gas mass spectrometer, SPI, VOCs, Dioxin, Explosives and chemical warfare agents detection, Trace detection,
	NO_2分子高灵敏度痕量探测技术研究期刊论文 OAI收割应用光学, 2014, 卷号: 35 作者: 董美丽; 徐学哲; 赵卫雄; 顾学军; 胡长进 \| 收藏 \| 浏览/下载：5/0 \| 提交时间：2023/11/10 laser spectroscopy incoherent broadband cavity-enhanced absorption spectroscopy NO_2 molecule high-sensitive trace detection 激光光谱非相干宽带腔增强吸收光谱 NO_2分子高灵敏度痕量探测
	Recent Advancement of Chemical Derivatization and Its Applications to High Sensitive Analysis of Peptide in Mass Spectrometry 期刊论文 OAI收割 chinese journal of analytical chemistry, 2012, 卷号: 40, 期号: 7, 页码: 1123-1129 作者: Qiao Xiao-Qiang; Wang Rui; Zhang Li-Hua; Yang Geng-Liang; Zhang Yu-Kui 收藏 \| 浏览/下载：28/0 \| 提交时间：2013/10/11 Chemical derivatization High sensitive detection Mass spectrometry Peptide Review
	Multi-parameters decoupling method with Lamb wave sensor for improving the selectivity of label-free liquid detection (EI CONFERENCE) 会议论文 OAI收割 2011 16th International Solid-State Sensors, Actuators and Microsystems Conference, TRANSDUCERS'11, June 5, 2011 - June 9, 2011, Beijing, China 作者: Zhou L. 收藏 \| 浏览/下载：24/0 \| 提交时间：2013/03/25 The anti-symmetric modes (A01 mode for low frequency A 03 mode for high frequency) and symmetric modes (S0 mode) produced by Lamb wave sensor are used to detect multi-parameters of a liquid such as its density sound velocity and viscosity. These modes are found to be very different to the parameters. For example the A01 mode is very sensitive to the liquid's density but the A03 mode is sensitive to its sound velocity. The measurements of the attenuation with S0 mode can give out liquid's viscosity after its density been determined by A 01 mode. That could be a way to distinguish an unknown liquid with high sensitivity or to solve the problem of the selectivity of label free detection on biosensors. 2011 IEEE.
	Correction method for detection of the frequencies of railway fsk signals (EI CONFERENCE) 会议论文 OAI收割 2008 9th International Conference on Signal Processing, ICSP 2008, October 26, 2008 - October 29, 2008, Beijing, China 作者: Yu J. 收藏 \| 浏览/下载：63/0 \| 提交时间：2013/03/25 In order to acquire the information of railway binary frequency-shift keying signals which include upper/down side frequencies and base low-frequency with high-accuracy a novel frequency detection algorithm for France UM-71 system is proposed. Combining fast Fourier transform with the ratio correction method the carrier frequency and the base frequency are obtained. Furthermore the hardware consumption has been decreased. And it possesses the advantage of simple algorithm and fast operation speed. Comparing with the detection of the base frequency the upper/down side frequency of railway signal is more difficult. Based on spectrum analysis and the spectrum correction a new method which adopts the sliding window is put forward in this paper. The absolute differences between the upper side frequencies and the down side frequencies obtained are regarded as the criterion for judgment. Then the set of data in which the maximum absolute value is is to be the result of the upper/down side frequency. Because the sliding window will go through every stage when the upper/down side frequency changes therefore it is not sensitive enough to the position of data which need to be transformed. Using the method mentioned above the experiment results show that the accuracy requirement of the side frequency is satisfied well. 2008 IEEE.