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	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.
	The Formation Mechanism of Ag/SBA-15 Nanocomposites Prepared via In-Situ pH-Adjusting Method 期刊论文 OAI收割 journal of nanoscience and nanotechnology, 2013, 卷号: 13, 期号: 7, 页码: 4573-4580 作者: Qu, Zhenping; Zhang, Xiaodong; Lv, Yang; Quan, Xie 收藏 \| 浏览/下载：28/0 \| 提交时间：2015/11/09 Ag/SBA-15 In-Situ Synthesis pH-Adjusting Mesoporous Materials The Formation Mechanism
	Motion mechanism analysis of a two-degree-of-freedom spherical motor (EI CONFERENCE) 会议论文 OAI收割 2nd International Conference on Information Engineering and Computer Science, ICIECS 2010, December 25, 2010 - December 26, 2010, Wuhan, China 作者: Guo K. 收藏 \| 浏览/下载：20/0 \| 提交时间：2013/03/25 The working principle of a two-degree-of-freedom piezoelectric spherical motor using only one piezoelectric element was analyzed. The resonance frequencies of the motor's plate type piezoelectric vibrator were calculated by finite element method. The computer simulation was executed to analyze the motion trajectory of the four contact points between the stator and the sphere. Simulation results verified that the four contact points can form timing reasonable elliptical trajectories which re designed to drive the sphere to form two rotation degrees of freedom. The conclusion indicated the formation of two-dimensional movement mechanism of the spherical motor. 2010 IEEE.
	Study on the influence and disposal method of the micro-cracks of optical components (EI CONFERENCE) 会议论文 OAI收割 4th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Advanced Optical Manufacturing Technologies, November 19, 2008 - November 21, 2008, Chengdu, China 作者: Xuan B.; Xie J.-J.; Xie J.-J.; Zhang H.; Zhang H. 收藏 \| 浏览/下载：25/0 \| 提交时间：2013/03/25 Micro-crack is one of the most effective factor to the intensity and service life of optical components. Owing to the micro-crack on surface actual strength of optical components is reduced severely even less than ten-percent of its theoretical strength. According to fracture mechanics the mechanisms of the formation and propagation of micro-crack and the growth theory of sub-critical micro-crack are discussed in the paper firstly. Based on practice an on-line test method disposing etching holes-the molecule-infiltrating method and the principles of acid-etching method disposing micro-crack are described. Followed by the demolishing mechanism of abrasives and a more reasonable removal redundancy of fine-grinding and polishing during optical production is given by using abrasives in different-size orderly. 2009 SPIE.
	Formation and characteristics of quantum dots of wide band gap II-VI semiconductor (EI CONFERENCE) 会议论文 OAI收割 Fifth International Conference on Thin Film Physics and Applications, May 31, 2004 - June 2, 2004, Shanghai, China Fan X. W.; Shan C. X.; Yang Y.; Zhang J. Y.; Liu Y. C.; Lu Y. M.; Shen D. Z. 收藏 \| 浏览/下载：28/0 \| 提交时间：2013/03/25 CdSe and ZnCdSe quantum dots (QDs) were grown under Stranski-Krastanow (S-K) mode by low-pressure metalorganic chemical vapor deposition (LP-MOCVD). The formation process of CdSe QDs below critical thickness was observed by atomic force microscopy (AFM). The formation mechanism of CdSe QDs below the critical thickness was due to the effect of surface diffusion and strain release. ZnCdSe QDs were grown based on the calculated critical thickness. Two kinds of variations in the ZnCdSe QDs appeared over time the Ostwald ripening process and dot formation process. ZnSeS dots were grown under Volmer-Weber (V-W) mode. With increasing the growth duration the size of dots becomes larger and the density decreases which is explained by virtue of the surface free energy.