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C.K.Tseng 《中国海洋湖沼学报》1983,1(2):190-197
The genus Geppellais a small group of tropical and subtropical algae.It was establishedby Boergesen in 1940 on the basis of its uncalciferous frond and its characteristic of annularattachments of the filaments,with G.mortensenii Boergesen as the type of the genus.Sincethen four more species have been described,namely,G.decussata Dawson(1959),G.echino-caulos Cribb(1960),G.yaeyamense Tanaka(1963),and G.japonica Tanaka et Itono(1977).The species G.decussata was reported by Dawson from Isla San Francisco(Gulf of California)and the Marshall Islands,central Pacific,and later removed by Tanaka and Itono(1977)from the genus Geppella because of the absence of blade and of annular attachments of 相似文献
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本文继续报道产于我国广东省西沙群岛的海产绿藻9种,除2种已有记载外,其余7种都是西沙群岛的新记录,其中1种为新种一簇囊缢丝藻Boodleopsis aggregata sp.nov.,2种为我国的新记录—太坦松藻Codium taitense Setchell,钱币状蕨藻Caulerpa nummularia (Harv. ) Reinke。 相似文献
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Resonance Induced by Edge Waves in Hua-Lien Harbor 总被引:2,自引:0,他引:2
Guan-Yu?ChenEmail author Chung-Ching?Chien Ching-Ho?Su Hsiang-Mao?Tseng 《Journal of Oceanography》2004,60(6):1035-1043
This article first reviews previous numerical studies on the resonance problem of Hua-Lien Harbor. All the research leads to the conclusion that resonance can be stimulated by 2-D infragravity waves. However, a literature survey suggests that outside the harbor these plane infragravity waves are too small to excite violent water-body movement inside. On the other hand, 3-D infragravity waves trapped along the coastline, also known as edge waves, are more likely to exist outside the harbor and their effect needs to be thoroughly discussed. Based on previous measurements, the response of Hua-Lien Harbor is best simulated using edge waves of 160 and 140 second periods and their resonance mechanisms are analyzed. The former case has a longitudinal resonant mode and hence the amplitude in the inner harbor is large. The latter case has a transverse mode in the outer basin and hence only berths in the outer basin are influenced. These features are both consistent with field measurement. Therefore, it is very likely that edge waves are responsible for the resonance of Hua-Lien Harbor. Finally, based on observation after the construction of the present offshore breakwaters, a theory is proposed to explain the trapping of incident edge waves, and a measure to further reduce the resonance is discussed. 相似文献
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于1992年4月一1993年4月,用液氮研磨-苯酚/氯仿抽提-异丙醇沉淀的方法提取青岛沿海产紫菜、真江蓠、龙须菜、海膜4种红藻的总DNA;利用Hoechst-CsCl密度梯度起离心法将叶绿体DNA与核DNA分开。对抽取的叶绿体DNA梯度组分电泳结果表明,真江蓠样品出现质粒的电泳条带。以透射电镜观察到闭会环状DNA图像(周长平均值为4.3×10-7m,约为1.3kb);分子杂交结果显示,真江蓠质位与其叶绿体DNA之间没有同源性,而与核DNA之间有一定同源性。 相似文献
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Non-linear seismic responses are described for three prototype, long, multiple-span, reinforced concrete, modern highway bridge structures, namely the 5/14 South Connector Overcrossing and the curved Figueroa Street Under-crossing as designed by the California Department of Transportation, and a straight version of the Figueroa Street Undercrossing. The analytical seismic responses are discussed and are correlated with the apparent prototype behaviour experienced during the San Fernando, California, earthquake of 9 February 1971. In particular, the causes of collapse of the 5/14 South Connector Overcrossing are identified and examined. Finally, based on parameter studies of the seismic responses of these structures, general conclusions and recommendations related to seismic design methodology are presented. 相似文献