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Phytochemical analysis and bioactivity of different ethanolic extracts from cannabidiol full-spectrum oil 期刊论文  OAI收割
JOURNAL OF MOLECULAR LIQUIDS, 2023, 卷号: 372, 页码: 7
作者:  Li, Hang;  Zhao, Qingsheng;  Chang, Senlin;  Wang, Liwei;  Zhao, Bing
  |  收藏  |  浏览/下载：0/0  |  提交时间：2023/05/19
On the Terrestrial Gamma Ray Flashes Preceding Narrow Bipolar Events 期刊论文  OAI收割
Geophysical Research Letters, 2021, 卷号: 48, 页码: e92160
作者:  HXMT
  |  收藏  |  浏览/下载：28/0  |  提交时间：2022/02/08
low frequency magnetic sferics  narrow bipolar events (NBEs)  relativistic feedback mechanism  Terrestrial Gamma ray Flashes (TGFs)  Abstract: Narrow bipolar events (NBEs) are occasionally reported to occur within a few ms after Terrestrial Gamma ray Flashes (TGFs), while the formation mechanism remains mysterious partially due to the lack of sufficient observations. Here, nine more TGFs of this scenario are reported with concurrent LF sferics and lightning location data. The gamma ray production in these TGFs preceded the occurrence of NBEs by a minimum of 60 µs up to 13.5 ms, and no other fast leader discharge was found within 20 ms before the TGF. The TGF preceded positive NBEs occurred at altitudes of 8.6-11 km in thunderstorms, likely in the high electric field (E field) region of lightning initiation. The analyses show that the NBE preceding TGFs bear harder energy spectrum with larger proportion of high energy photons than EIP related TGFs produced in association with lightning leader. Our findings support the relativistic feedback mechanism of gamma ray generation in the large scale thunderstorm E field.  
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 AJ = 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 RNIR ? 0.025 (fluence index ?0.35).  
UPLC-MS/MS analysis for antioxidant components of Lycii Fructus based on spectrum-effect relationship 期刊论文  OAI收割
Talanta, 2018, 期号: 180, 页码: 389-395
作者:  Zhang XF(张弦飞);  Chen J(陈娟);  Yang JL(杨军丽);  Shi YP(师彦平)
  |  收藏  |  浏览/下载：36/0  |  提交时间：2018/06/11
The angular velocity estimation principal of -- filter based on high sampling rate (EI CONFERENCE) 会议论文  OAI收割
2011 2nd International Conference on Mechanic Automation and Control Engineering, MACE 2011, July 15, 2011 - July 17, 2011, Inner Mongolia, China
作者:  Zhang Y.
收藏  |  浏览/下载：28/0  |  提交时间：2013/03/25
In order to get angular velocity of stabilization servo mechanism from angular position sensors  -- filter and its angular velocity transfer function were predigested. Combing with optimum parameters  -- filter based on high sampling rate was established  the effect of and sample rate on filter nature frequency were evaluated. According to the requirements of stabilization platform  the principle of steady and transient tracking filter differential were proved. With the hypothesis of constant acceleration  the frequency characteristics of angular velocity transfer function were analyzed  three-dimensional Kalman filter was simplified  and the filter parameters were designed. The results show that when the spectrum of input signal was lower than 6rad/s  parameters was 0.02  and sampling period were 0.08ms and 0.1ms respectively  the filter can realize differential exactly  when the spectrum was 9rad/s  the precision was no less than 1.1%  the phase leading of angular position was no less than 70  the natural frequency should be higher than the cut-off frequency of stabilization platform was two or three times. In the engineering of electro-optical stabilization servo mechanism  -- filter has properties of tracking differential  and reached the requirement of platform angular velocity estimation. Also it is one of the effective methods to get angular velocity from angular position sensors. 2011 IEEE.  
Synthesis and Characterization of Metallofullerene Derivatives La@C-82-(C4N2H8)(m)H-n 期刊论文  OAI收割
CHEMICAL JOURNAL OF CHINESE UNIVERSITIES-CHINESE, 2010, 卷号: 31, 期号: 10, 页码: 1976-1981
作者:  Dai, FC;  Chang, F;  Ren TX(任同祥);  Sun BY(孙宝云);  Ren, TX
收藏  |  浏览/下载：86/0  |  提交时间：2016/06/29
西藏产雪莲花的化学成分研究 学位论文  OAI收割
博士, 2009
达娃卓玛
收藏  |  浏览/下载：73/0  |  提交时间：2010/11/24
Real-time restoration for motion-blurred color images by multichannel combination processing (EI CONFERENCE) 会议论文  OAI收割
1st International Workshop on Education Technology and Computer Science, ETCS 2009, March 7, 2009 - March 8, 2009, Wuhan, Hubei, China
作者:  Sun H.;  Sun H.;  Li S.
收藏  |  浏览/下载：46/0  |  提交时间：2013/03/25
A fast algorithm is proposed to restore the color images  degraded in a deterministic way by motion- blurred  by multichannel combination processing. Based on the color space conversion model  the point spread functions of the image motion on each plane of YUV422 image can be achieved. The U  V plane of YUV422 images are combined to form a new UV plane which has the same size as Y plane. Then  the Y  UV plane are packed into a two dimensional complex array which can be transformed directly by FFT and result a composite frequency spectrum. Wiener filter is applied to filter Y  UV spectrums separated from the composite spectra. On Graphics Processing Unit (GPU) platform  the proposed algorithm can restore a 1024x1024 24-bit motion-blurred color image in 7.95ms  and the PSNR of the restored image is 27.12 which reveals a good restoration performance. 2009 IEEE.  
Carbonization of pre-oxidized polyacrylonitrile fibers 期刊论文  iSwitch采集
New carbon materials, 2008, 卷号: 23, 期号: 2, 页码: 121-126
作者:  Wen Yue-fang;  Cao Xia;  Yang Yong-gang;  Li Hui;  Guo Jian-qiang
收藏  |  浏览/下载：29/0  |  提交时间：2019/05/10
Structure analysis on complexes of xanthone glycosides and metal ions using Electrospray ionization tandem mass Spectrometry 期刊论文  OAI收割
polish journal of chemistry, 2007, 卷号: 81, 期号: 10, 页码: 1687-1700
作者:  Sun, Y. G.;  Zhang, X.;  Wang, L.;  Xue, X. Y.;  Xiao, H. B.
收藏  |  浏览/下载：24/0  |  提交时间：2010/11/30