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	Periodicity Search on X-Ray Bursts of SGR J1935+2154 Using 8.5 yr of Fermi/GBM Data 期刊论文 OAI收割 The Astrophysical Journal, 2021, 卷号: 923, 页码: L30 作者: HXMT \| 收藏 \| 浏览/下载：25/0 \| 提交时间：2022/02/08 2008 1471 Astrophysics - High Energy Astrophysical Phenomena Abstract: We performed a systematic search for X-ray bursts of the SGR J1935+2154 using the Fermi Gamma-ray Burst Monitor continuous data dated from 2013 January to 2021 October. Eight bursting phases, which consist of a total of 353 individual bursts, are identified. We further analyze the periodic properties of our sample using the Lomb-Scargle periodogram. The result suggests that those bursts exhibit a period of ~238 days with a ~63.2% duty cycle. Based on our analysis, we further predict two upcoming active windows of the X-ray bursts. Since 2021 July, the beginning date of our first prediction has been confirmed by the ongoing X-ray activities of the SGR J1935+2154.
	Some observations on the size effects in nanotwined metals and their theoretical explanation 会议论文 OAI收割 23rd International Congress of Theoretical and Applied Mechanics, 中国北京/Beijing, China, 2012-08-19 作者: Wei YJ(魏宇杰) 收藏 \| 浏览/下载：17/0 \| 提交时间：2014/04/02 theoretical their explanation effects system suitable amount higher dimensional achieved dimensions deformed novel finding change limited stronger migration exhibit sizes
	A video synthesis method for flow patterns (EI CONFERENCE) 会议论文 OAI收割 2010 2nd IEEE International Conference on Network Infrastructure and Digital Content, IC-NIDC 2010, September 24, 2010 - September 26, 2010, Beijing, China 作者: Chen J.; Liu J.; Yu D.; Yu D.; Li J. 收藏 \| 浏览/下载：26/0 \| 提交时间：2013/03/25 This paper presents a new video synthesis method for flow patterns. We can use it to synthesize video of natural phenomena that exhibit continuous flow patterns. It is based on flow-based video synthesis algorithm and combines partial ideas of graph cuts algorithm. This algorithm can process input videos of natural phenomena of flow patterns (e.g. rivers flames and waterfalls) and synthesize more realistic and active seamless video of arbitrary length than other algorithms. It is simple to implement. The results show that our method can produce satisfactory effects based on user inputs. 2010 IEEE.
	Electron transport in polymer-derived amorphous silicon oxycarbonitride ceramics (EI CONFERENCE) 会议论文 OAI收割作者: Zhang L.; Wang Y.; Wang Y.; Wang Y.; Wang Y. 收藏 \| 浏览/下载：69/0 \| 提交时间：2013/03/25 The electron transport behavior of polymer-derived amorphous silicon oxycarbonitride ceramics is studied by measuring their temperature-dependent electrical conductivities. The experimental results are analyzed using theoretical models. The results reveal that the materials exhibit three conduction mechanisms: conduction in extended states conduction in band tails and conduction in localized states. Particularly it is found that in a low-temperature regime the conduction of the materials follows a band tail hopping mechanism rather than the previously assumed variable range hopping mechanism. The results also reveal that energy gaps such as EC-E F and EC-EA decrease with increasing pyrolysis temperature. 2009 The American Ceramic Society.
	Energy transfer and red phosphorescence in strontium aluminates doped with Cr3+, Eu2+ and Dy3+ (EI CONFERENCE) 会议论文 OAI收割 Dielectrics in Emerging Technologies -and- Persistent Phosphors - International Symposia, May 15, 2005 - May 20, 2005, Quebec City, QC, Canada 作者: Wang X.; Wang X.; Wang X.; Zhang X.; Zhang X. 收藏 \| 浏览/下载：34/0 \| 提交时间：2013/03/25 Cr3+ activated red (694 nm) long persistent phosphorescence originating from 2E-4A2 transition is observed in 4SrO·7Al2O3: Cr3+ Eu2+ Dy3+ system. It is demonstrated that the red phosphorescence is resulted from the conversion of Eu2+ activated blue phosphorescence through persistence energy transfer from Eu2+ to Cr3+. The excitation spectra of the 694 nm emission exhibit strong f-d band of Eu 2+ indicating the existence of the energy transfer. The dependence of lifetimes and intensities of the red and blue emissions on Cr3+ concentrations are studied. The intensity ratio of the red to blue emission bands obtained from photoluminescence spectra is in good agreement with that obtained from fluorescence lifetime measurements. The decay curves of the red phosphorescence at 694nm are also studied.
	Upconversion luminescence properties of Y2O3:Yb 3+, Er3+ nanostructures (EI CONFERENCE) 会议论文 OAI收割作者: Cui Y.; Wang Y.; Wang Y.; Wang Y.; Wang Y. 收藏 \| 浏览/下载：24/0 \| 提交时间：2013/03/25 Cubic Y2O3 nanostructures doped with Yb3+ and Er3+ ions were synthesized by a facile hydrothermal method. Three distinct shapes such as nanotubes nanospheres and nanoflakes formed in the products by adjusting the pH value of reacting solution. Powder X-ray diffraction analyses indicate that all the three nanostructures are pure cubic phase while electron microscopy measurements confirm the formation of different morphologies. These nanostructures exhibit strong visible upconversion luminescence under the excitation of a 978-nm diode laser. In Yb3+- and Er3+- codoped Y2O3 nanocrystals the relative intensity of green emission became stronger as the size and morphology of sample changed from tubes to flakes. 2006 Elsevier B.V. All rights reserved.
	Tandem electroabsorption modulators integrated with DFB laser by ultra-low-pressure selective-area-growth MOCVD for 10 GHz optical short pulse generation 期刊论文 OAI收割 semiconductor science and technology, 2005, 卷号: 20, 期号: 8, 页码: 882-885 Zhao, Q; Pan, JQ; Zhang, J; Zhou, GT; Wu, J; Wang, LF; Wang, W 收藏 \| 浏览/下载：125/47 \| 提交时间：2010/03/17 摘要: A novel device of tandem MQW EAMs monolithically integrated with a DFB laser is fabricated by an ultra-low-pressure (22 mbar) selective area growth MOCVD technique. Experimental results exhibit superior device characteristics with low threshold of 19 mA output light power of 4.5 mW and over 20 dB extinction ratio when coupled to a single mode fibre. Moreover over 10 GHz modulation bandwidth is developed with a driving voltage of 2 V. Using this sinusoidal voltage driven integrated device 10 GHz repetition rate pulse with an actual width of 13.7 ps without any compression elements is obtained.
	V-shaped electro-optic characteristics in FLC gels (EI CONFERENCE) 会议论文 OAI收割作者: Li J.; Li J.; Li J.; Xuan L. 收藏 \| 浏览/下载：34/0 \| 提交时间：2013/03/25 The effects of polymer network formed under UV irradiation with electric field application ( 50V 5Hz) to ferroelectric liquid crystal (FLC) molecules orientation and electrooptic characteristics have been studied. The polymer network formed in SmC*phase is anisotropic and fibrils-like and a typical striped texture was observed in the cell. The FLC gels exhibit a symmetric V-shaped electrooptic characteristics with thresholdless voltage and high contrast ratio (40:1). A theory explanation of the unique properties is given by establishing a molecular orientation model and conducting a computer simulation. A good fitting of the electrooptic dynamic response of FLC gels has been obtained by introducing a potential (bulk anchoring energy) originated from the photo-cured polymer network. 2002 Taylor Francis.