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过去200ka北半球δ^(18)O海温谱及其数值模拟 被引量:4
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作者 戴新刚 《冰川冻土》 CSCD 北大核心 2000年第4期317-322,共6页
冰期和间冰期交替循环是第四纪古气候变化的基本特征 .大洋底部沉积物中的有孔虫δ18O记录表明了这种循环具有约 10 0ka ,41ka和 2 3ka等几个主要周期成分 ,它们均位于Milankovitch频率带上 .用δ18O记录恢复的海温谱不仅随纬度变化 ,... 冰期和间冰期交替循环是第四纪古气候变化的基本特征 .大洋底部沉积物中的有孔虫δ18O记录表明了这种循环具有约 10 0ka ,41ka和 2 3ka等几个主要周期成分 ,它们均位于Milankovitch频率带上 .用δ18O记录恢复的海温谱不仅随纬度变化 ,而且冷季与暖季之间存在着明显的差别 .用一个由海、冰、气耦合的二维古气候模式模拟出了δ18O海温谱的主要特征 ,在一定程度上检验了Mi lankovitch的天文古气候学说 .模式在没有地形的条件下能成功地模拟出 10 0ka周期成分 ,一方面说明青藏高原的隆起并不是 10 0ka古气候振荡出现的充分条件 ;另一方面表明它很可能是海 -冰 -气气候子系统之间相互作用的产物 . 展开更多
关键词 古气候模拟 Milankovitch学说 海温谱 δ^(18)O记录
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Identification of Fucans from Four Species of Sea Cucumber by High Temperature ~1H NMR 被引量:2
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作者 WU Nian CHEN Shiguo +3 位作者 YE Xingqian LI Guoyun YIN Li'ang XUE Changhu 《Journal of Ocean University of China》 SCIE CAS 2014年第5期871-876,共6页
Acidic polysaccharide, which has various biological activities, is one of the most important components of sea cucumber. In the present study, crude polysaccharide was extracted from four species of sea cucumber from ... Acidic polysaccharide, which has various biological activities, is one of the most important components of sea cucumber. In the present study, crude polysaccharide was extracted from four species of sea cucumber from three different geographical zones, Pearsonothuria graeffei(Pg) from Indo-Pacific, Holothuria vagabunda(Hv) from Norwegian Coast, Stichopus tremulu(St) from Western Indian Ocean, and Isostichopus badionotu(Ib) from Western Atlantic. The polysaccharide extract was separated and purified with a cellulose DEAE anion-exchange column to obtain corresponding sea cucumber fucans(SC-Fucs). The chemical property of these SC-Fucs, including molecular weight, monosaccharide composition and sulfate content, was determined. Their structure was compared simply with fourier infrared spectrum analyzer and identified with high temperature 1H nuclear magnetic resonance spectrum analyzer(NMR) and room temperature 13 C NMR. The results indicated that Fuc-Pg obtained from the torrid zone mainly contained 2,4-O-disulfated and non-sulfated fucose residue, whereas Fuc-Ib from the temperate zone contained non-, 2-O- and 2,4-O-disulfated fucose residue; Fuc-St from the frigid zone and Fuc-Hv from the torrid zone contained mainly non-sulfated fucose residue. The proton of SC-Fucs was better resolved via high temperature 1H NMR than via room temperature 1H NMR. The fingerprint of sea cucumber in different sea regions was established based on the index of anomer hydrogen signal in SC-Fucs. Further work will help to understand whether there exists a close relationship between the geographical area of sea cucumber and the sulfation pattern of SC-Fucs. 展开更多
关键词 sea cucumber sulfated fucan composition analysis 1H NMR IDENTIFICATION
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RELATIONSHIP BETWEEN INTERANNUAL VARIATION OF MERIDIONAL WIND ANOMALIES IN TROPICAL PACIFIC AND SSTA
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作者 张祖强 丁一汇 +1 位作者 赵宗慈 黄山江 《Journal of Tropical Meteorology》 SCIE 2002年第2期180-190,共11页
The Singular Spectrum Analysis (SSA) method is used to conduct studies of periodicity of the SST and meridional winds in tropical Pacific Ocean. The results show that the air-sea system for the Pacific varies on quasi... The Singular Spectrum Analysis (SSA) method is used to conduct studies of periodicity of the SST and meridional winds in tropical Pacific Ocean. The results show that the air-sea system for the Pacific varies on quasi-4-year, quasi-2-year and interannual scales, with the quasi-4-year scale having the highest variability. Depending on the scale, the wind field has a varying degree of association with the SST anomalies. Difference is also found in the evolution of phase. In addition, the work discusses the difference in SSTA resulted from wind fields for quasi-4-year and quasi-2-year components. 展开更多
关键词 air-sea interactions ENSO SSA
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