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Physiological Adaptation of Habitat by Ion Distribution in the Leaves of Four Ecotypes of Reed (Phragmites australis) 被引量:9
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作者 郑文菊 陈国仓 +3 位作者 张承烈 胡玉熹 李凌浩 林金星 《Acta Botanica Sinica》 CSCD 2002年第1期82-87,共6页
The ion levels in the epidermal bulliform cells of epidermis, mesophyll cells and cells of the vascular bundle sheath of four ecotypes of reed (Phragmites australis (Cav.) Trin. ex Steud.) were determined by means of ... The ion levels in the epidermal bulliform cells of epidermis, mesophyll cells and cells of the vascular bundle sheath of four ecotypes of reed (Phragmites australis (Cav.) Trin. ex Steud.) were determined by means of X_ray microanalysis. The results indicated that higher K +, Na +, Ca 2+ , Mg 2+ and Cl - were distributed in the vascular bundle sheath cells than in mesophyll cells and epidermal bulliform cells of the swamp ecotype. Higher Ca 2+ was found in the bulliform cells than in mesophyll cells and vascular bundle sheath cells, higher Mg 2+ in the mesophyll cells and higher K +, Na + and Cl - in the vascular bundle sheath cells of the dune ecotype. Higher Na + and Mg 2+ was determined in the mesophyll cells than in the bulliform cells and vascular bundle sheath cells, and higher K +, Ca 2+ and Cl - in the vascular bundle sheath cells of the light salt meadow ecotype. In the heavy salt meadow ecotype, higher Na + and Mg 2+ were accumulated in the bulliform cells than in mesophyll cells and vascular bundle sheath cells, but higher K +, Ca 2+ and Cl - in the mesophyll cells. Furthermore, the distributional conditions of the above five ions in leaf cells of the four ecotypes and their significance in the physiological adaptation of reed to habitat were discussed in detail. 展开更多
关键词 reed ( Phragmites australis ) ion distribution physiological adaptation ECOTYPES x_ray micro_analysis
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SIMULATION AND STUDY OF THE MODULUS OF ELASTICITY OF NANOCRYSTALLINE MATERIALS 被引量:1
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作者 孙伟 常明 杨保和 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1999年第5期95-101,共7页
In this paper, a molecular dynamics simulations are provided for atomic structure of nanocrystals(1~3nm)by which t he lattice parameter of X_ray diffraction, cohesive energy and modulus of elas ticity were computed... In this paper, a molecular dynamics simulations are provided for atomic structure of nanocrystals(1~3nm)by which t he lattice parameter of X_ray diffraction, cohesive energy and modulus of elas ticity were computed. The results show that the structure of grain and grain bou ndaries in the same in both nanocrystal and coarse grain materials. The decrease of grain size and the increase volume fraction of grain boundaries lead to a se ries of different features, the modulus of elasticity of nanocrystalline materia ls have been found to be much reduced. 展开更多
关键词 molecular dynamics nanocrystal x_ray modulu s of elasticity
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Lake Shira Level Changes in Late Holocene
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作者 Anrey DARIN Ivan KALUGIN +5 位作者 Natalya MAKSIMOVA Tatiana MARKOVICHv Yakov RAKSHUN Dmitryi SOROKOLETOV Fedor DARIN Denis RAGOZIN 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2014年第S1期3-4,共2页
1 Introduction Meromictic Shira Lake is a good represfor detail climate modeling due to its locainformation and annually laminated bottomsediment column of 155 cm in length wahammer corer in the deepest(24 m)central i... 1 Introduction Meromictic Shira Lake is a good represfor detail climate modeling due to its locainformation and annually laminated bottomsediment column of 155 cm in length wahammer corer in the deepest(24 m)central in 2009.2 Sample Preparations and Measuring 展开更多
关键词 Lake Shira VARVE synchrotron radiation scanning x_ray fluorescence microanalysis.
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The Study Internal Structure of the Annual Layers in Lake Sediments Using Synchrotron Radiation with X-ray Focusing Optics
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作者 Fedor DARIN Ivan KALUGIN +1 位作者 Andrey DARIN Yakov RAKSHUN 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2014年第S1期5-6,共2页
1 Introduction Annually laminated(varve)sedimentary deposits are considered as one of the most important archives,since they offer precise temporal information(years)in combination with high time resolutions.Bottom se... 1 Introduction Annually laminated(varve)sedimentary deposits are considered as one of the most important archives,since they offer precise temporal information(years)in combination with high time resolutions.Bottom sediments of the lakes contain detailed geochemical information on 展开更多
关键词 VARVE .synchrotron radiation scanning x_ray fluorescence microanalysis focusing X-ray optics.
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Coordinated observations of large scale coronal brightening and H_αsurge
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作者 Jiong Qiu Aoao Xu 《Chinese Science Bulletin》 SCIE EI CAS 1998年第23期1969-1973,共0页
During the post_flare phase of an eruptive two_ribbon flare on February 4, 1995, the Soft X_ray Telescope (SXT) on board Yohkoh observed the rapid brightening of a set of large scale coronal loops (150-200 Mm in lengt... During the post_flare phase of an eruptive two_ribbon flare on February 4, 1995, the Soft X_ray Telescope (SXT) on board Yohkoh observed the rapid brightening of a set of large scale coronal loops (150-200 Mm in length). Simultaneously, coordinated ground_based observations reveal a co_incident H α surge event. To our knowledge, no H α surge event coincident with the large scale coronal brightening observed by Yohkoh has been reported. The possible mechanisms for the concurrent cool plasma ejection and the filling of the hot coronal loops are discussed. It is found that magnetic reconnection between a magnetic arcade and an overlying large scale coronal structure may account for the coincident events. Big amount of magnetic energy was converted into both mechanic energy (about 10 22 J) in the mass ejection and thermal radiation (10 23 J) contained in the large SXR loops. 展开更多
关键词 Sun: activity SUN FLARES x_rays COORDINATED observation.
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