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A Comparative Study of Dispersion Characteristics Determination of a Trapezoidally Corrugated Slow Wave Structure Using Different Techniques
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作者 Md.Ghulam Saber Rakibul Hasan Sagor Md.Ruhul Amin 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第1期132-135,共4页
The linear dispersion relation of a trapezoidally corrugated slow wave structure (TCSWS) is analyzed and presented. The size parameters of the TCSWS are chosen in such a way that they operate in the x-band frequency... The linear dispersion relation of a trapezoidally corrugated slow wave structure (TCSWS) is analyzed and presented. The size parameters of the TCSWS are chosen in such a way that they operate in the x-band frequency range. The dispersion relation is solved by utilizing the Rayleigh-Fourier method by expressing the radial function in terms of the Fourier series. A highly accurate synthetic technique is also applied to determine the complete dispersion characteristics from experimentally measured resonances (cold test). Periodic structures resonate at specific frequencies when the terminals are shorted numerical calculation, synthetic technique and cold appropriately. The dispersion characteristics obtained from test are compared, and an excellent agreement is achieved. 展开更多
关键词 of on A Comparative Study of Dispersion Characteristics Determination of a Trapezoidally Corrugated Slow Wave Structure Using Different techniques in been IS
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APPLICATION OF 2D-NMR TECHNIQUES IN THE STRUCTURE DETERMINATION OF HYPODEMATINE
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作者 Ya Min CHEN Ying Hua LU Yan Jun CHEN Cun Sheng MA (Jining Medical College,Shandong,272113) De Quan YU (Institute of Materia Medica,Chinese Academy of Medical Sciences,Beijing,100050) 《Chinese Chemical Letters》 SCIE CAS CSCD 1990年第3期221-222,共2页
An alkaloid with a novel structure,named Hypodematine,was isolated from Hypodematium sinense Iwatsuki(belonging to Thelypterdaceae).Its structure was elucidated by means of the ~1H-~1H COSY' ~1H-^(13)C COSY and lo... An alkaloid with a novel structure,named Hypodematine,was isolated from Hypodematium sinense Iwatsuki(belonging to Thelypterdaceae).Its structure was elucidated by means of the ~1H-~1H COSY' ~1H-^(13)C COSY and long-range ~1H-^(13)C COSY spectroscopy to have the skeleton of benzo-aza-cyclooctatetraene with a phenyl substituent.Such basic structure has not been found in the na- tural product before. 展开更多
关键词 NMR APPLICATION OF 2D-NMR techniques IN THE STRUCTURE DETERMINATION OF HYPODEMATINE
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Geostructures, dynamics and risk mitigation of high-altitude and long- runout rockslides 被引量:5
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作者 Yueping Yin Bin Li +3 位作者 Yang Gao Wenpei Wang Shilin Zhang Nan Zhang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第1期66-101,共36页
Long-runout rockslides at high altitude could cause disaster chain in river basins and destroy towns and major infrasturctures.This paper firstly explores the initiation mechanism of high-altitude and long-runout rock... Long-runout rockslides at high altitude could cause disaster chain in river basins and destroy towns and major infrasturctures.This paper firstly explores the initiation mechanism of high-altitude and long-runout rockslides.Two types of sliding-prone geostructure models,i.e.the fault control type in orogenic belt and the fold control type in platform area,are proposed.Then,large-scale experimental apparatus and associated numerical simulations are conducted to understanding the chain-style dynamics of rockslide-debris avalanche-debris flow.The results reveal the fragmentation effects,the rheological behaviors and the boundary layer effect of long-runout avalanche-debris flow.The dynamic character-istics of quasi-static-transition-inertia state and solid-liquid coupling in rapid movement of rockslide-debris avalanche-debris flow are investigated.Finally,the risk mitigation strategy of the non-structure and structure for resilient energy dissipation are illustrated for initiation,transition and deposition zones.The structural prevention and mitigation methods have been successfully applied to the high-altitude and long-runout rockslides in Zhouqu and Maoxian of the Wenchuan earthquake zone,as well as the other major geohazards in Qinghai-Tibet Plateau and its adjacent areas. 展开更多
关键词 ROCKSLIDE High-altitude and long-runout Sliding-prone geostructure Large-scale experimental apparatus Risk mitigation strategy structural prevention technique
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LAMOST spectral survey——An overview 被引量:48
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作者 Gang Zhao Yong-Heng Zhao +2 位作者 Yao-Quan Chu Yi-Peng Jing Li-Cai Deng 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2012年第7期723-734,共12页
LAMOST (Large sky Area Multi-Object fiber Spectroscopic Telescope) is a Chinese national scientific research facility operated by National Astronomical Observatories, Chinese Academy of Sciences (NAOC). After two ... LAMOST (Large sky Area Multi-Object fiber Spectroscopic Telescope) is a Chinese national scientific research facility operated by National Astronomical Observatories, Chinese Academy of Sciences (NAOC). After two years of commis- sioning beginning in 2009, the telescope, instruments, software systems and opera- tions are nearly ready to begin the main science survey. Through a spectral survey of millions of objects in much of the northern sky, LAMOST will enable research in a number of contemporary cutting edge topics in astrophysics, such as discovery of the first generation stars in the Galaxy, pinning down the formation and evolution history of galaxies - especially the Milky Way and its central massive black hole, and look- ing for signatures of the distribution of dark matter and possible sub-structures in the Milky Way halo. To maximize the scientific potential of the facility, wide national par- ticipation and international collaboration have been emphasized. The survey has two major components: the LAMOST ExtraGAlactic Survey (LEGAS) and the LAMOST Experiment for Galactic Understanding and Exploration (LEGUE). Until LAMOST reaches its full capability, the LEGUE portion of the survey will use the available ob- serving time, starting in 2012. An overview of the LAMOST project and the survey that will be carried out in the next five to six years is presented in this paper. The sci- ence plan for the whole LEGUE survey, instrumental specifications, site conditions, and the descriptions of the current on-going pilot survey, including its footprints and target selection algorithm, will be presented as separate papers in this volume. 展开更多
关键词 techniques spectroscopic -- Galaxy: structure -- Galaxy: evolution --Galaxy: disk -- spectroscopy
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LAMOST Experiment for Galactic Understanding and Exploration (LEGUE)——The survey's science plan 被引量:18
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作者 Li-Cai Deng Heidi Jo Newberg +21 位作者 Chao Liu Jeffrey L. Carlin Timothy C. Beers Li Chen Hsu-Tai Lee Carl J. Grillmair Puragra Guhathakurta] Zhan-Wen Han Jin-Liang Hou Sebastien Lepine Jing Li Xiao-Wei Liu Kai-Ke Pan J. A. Sellwood Bo Wang Hong-Chi Wang Fan Yang Brian Yanny Hao-Tong Zhang Yue-Yang Zhang Zheng Zheng Zi Zhu 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2012年第7期735-754,共20页
We describe the current plans for a spectroscopic survey of millions of stars in the Milky Way galaxy using the Guo Shou Jing Telescope (GSJT, formerly calledthe Large sky Area Multi-Object fiber Spectroscopic Telesc... We describe the current plans for a spectroscopic survey of millions of stars in the Milky Way galaxy using the Guo Shou Jing Telescope (GSJT, formerly calledthe Large sky Area Multi-Object fiber Spectroscopic Telescope -- LAMOST). The survey will obtain spectra for 2.5 million stars brighter than r 〈 19 during dark/grey time, and 5 million stars brighter than r 〈 17 or J 〈 16 on nights that are moonlit or have low transparency. The survey will begin in the fall of 2012, and will run for at least four years. The telescope's design constrains the optimal declination range for observations to 10~ 〈 di 〈 50~, and site conditions lead to an emphasis on stars in the direction of the Galactic anticenter. The survey is divided into three parts with different target selection strategies: disk, anticenter, and spheroid. The resulting dataset will be used to study the merger history of the Milky Way, the substructure and evolution of the disks, the nature of the first generation of stars through identification of the lowest metallicity stars, and star formation through study of open clusters and OB associations. Detailed design of the LAMOST Experiment for Galactic Understanding and Exploration (LEGUE) survey will be completed in summer 2012, after a review of the results of the pilot survey. 展开更多
关键词 techniques spectroscopic -Galaxy: structure - Galaxy: evolution -Galaxy: kinematics and dynamics -- Galaxy: disk -- Galaxy: halo -- spectroscopy
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Studying solutions for the fatigue of the FAST cable-net structure caused by the process of changing shape 被引量:3
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作者 Peng Jiang Ren-Dong Nan +1 位作者 Lei Qian You-Ling Yue 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2015年第10期1758-1772,共15页
The Five-hundred-meter Aperture Spherical Radio Telescope (FAST) is supported by a cable-net structure, whose change in shape leads to a stress range of approximately 500 MPa. This stress range is more than twice th... The Five-hundred-meter Aperture Spherical Radio Telescope (FAST) is supported by a cable-net structure, whose change in shape leads to a stress range of approximately 500 MPa. This stress range is more than twice the standard recom- mended value. The cable-net structure is thus the most critical and fragile part of the FAST reflector system. In this study, we first search for a more appropriate deforma- tion strategy that reduces the stress amplitude generated by the process of changing shape. Second, we roughly estimate the tracking trajectory of the telescope during its service life, and conduct an extensive numerical investigation to assess the require- ments for fatigue resistance. Finally, we develop a new type of steel cable system that satisfies the cable requirements for construction of FAST. 展开更多
关键词 five-hundred-meter aperture spherical radio telescope -- fatigue resis-tance -- astronomical techniques and approaches -- cable-net structure -- finite ele-ment
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Determination of microcapsule physicochemical, structural, and mechanical properties 被引量:6
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作者 Andrew Gray Stefan Egan +1 位作者 Serafim Bakalis Zhibing Zhang 《Particuology》 SCIE EI CAS CSCD 2016年第1期32-43,共12页
Research into the fundamental properties of microcapsules and use of the results to develop a wide variety of products in industries such as printing, fast-moving consumer goods, construction, pharmaceuticals, and agr... Research into the fundamental properties of microcapsules and use of the results to develop a wide variety of products in industries such as printing, fast-moving consumer goods, construction, pharmaceuticals, and agrochemicals is a dynamic and ever-progressing field of study. For microcapsules to be effective in providing protection from harsh environments or delivering large payloads, it is essential to have a good understanding of their properties to enable quality control during formulation, storage, and applications. This review aims to outline the commonly used techniques for determining the physicochemical, struc- tural, and mechanical properties of microcapsules, and highlights the interlinked nature of these three areas with respect to the end-use industrial application. This review provides information on techniques that are well supported in the literature, and also examines microcapsule analytical techniques that will become more prevalent as a result of new technological developments or extensions from other areas of study. 展开更多
关键词 Characterization Chemical composition Experimental technique Mechanical properties Microcapsule Physical structure
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Studies on the primary structure of chicken apolipoprotein A-I using HPLC technique
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作者 KIM.T.W. 《Chinese Journal of Chemistry》 SCIE CAS CSCD 1990年第3期251-258,共0页
The complete amino acid sequence of chicken plasma apolipoprotein(apo)A-I was determined by sequencing overlapping peptide fragments produced by trypsin,S.aureus V8 protease, and cyanogen bromide cleavage respectively... The complete amino acid sequence of chicken plasma apolipoprotein(apo)A-I was determined by sequencing overlapping peptide fragments produced by trypsin,S.aureus V8 protease, and cyanogen bromide cleavage respectively.All of the peptide fragments were purified on a Waters or on a Beckman HPLC system with a Vydae C_(18) column using 0.1% TFA in water as buffer A,and 0.08% TFA in 95% acetomtrile and 5% water as buffer B.Most of the peaks separated by these systems were pure.The partially purified fractions were subjected to rechromatography with a Hypersil ODS column using 0.005M sodium phosphate,pH 6.0,as buffer A,and 90% acetonitrile and 10% water as buffer B.The N-terminus of chicken apo A-I was determined to be aspartic acid by directly sequencing the intact protein up to 30 residues,while the C-terminus was identified as alanine by carboxypeptidase Y cleavage.There are 240 amino acid residues in mature chicken apo A-I.By direct analysis of cyanogen bromide peptide,we also determined the sequence of a 6 amino acid prosegment,which is present at approximately 10% of the molar amount of the mature protein in chicken plasma. 展开更多
关键词 Studies on the primary structure of chicken apolipoprotein A-I using HPLC technique HPLC
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