黑鲷早期鳞被的形成     

丁彦文  李加儿  区又君 《热带海洋学报》1991,(3)

黑鲷Sparus macrocephalus(Basilewsky)幼苗鳞被最早出现的部位是在躯干部胸鳍基后至肛门直上方的侧线处。黑鲷只具一个鳞被起始中心。最早出现鳞片的个体为体长9.5—14.1mm,平均11.51±0.85mm,全长11.2—16.5mm,平均13.65±1.01mm,孵后日龄23—35d。鳞被发育完全时的最小个体为体长12.1—18.5mm,平均14.57±1.55mm,全长14.8—23.5mm,平均17.99±2.17mm,孵后日龄27—42d。  相似文献   

Swimming behaviour and target strength of isada krill (Euphausia pacifica)   总被引：1，自引：0，他引：1  

Miyashita  Kazushi; Aoki  Ichiro; Inagaki  Tadashi 《ICES Journal of Marine Science》1996,53(2):303-308

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气候转型与早期人类迁徙   总被引：4，自引：0，他引：4  

吴文祥  刘东生 《海洋地质与第四纪地质》2001,21(4):103-109

目前的旧石器考古证据表明，更新世早期可能发生了两次人类迁徙浪潮，时间分别在1.8-1.6MaBP和1.0MaBP左右，第一阶段，古人类演化为直立人并开始走出非洲、迁徙至其它中低纬度的热带－亚热带地区；第二阶段，直立人开始占据中高纬度的温带和干旱－半干旱地区。这两个阶段也是第四纪气候发生转型、环境产生重大调整的时期。二者在发生时间上的一致性揭示了它们之间的内在联系，推测气候转型时期环境转变是这两次人类迁徙浪潮的主要驱动力。  相似文献   

Equilibrium constants of triethanolamine in major seawater salts     

I. Brandariz  P. Castro  M. Montes  F. Penedo  M.E. Sastre de Vicente 《Marine Chemistry》2006,102(3-4):291-299

Acid–base equilibrium constants of triethanolamine (TEA) have been determined by potentiometric titrations with a glass electrode, at 25 °C. Ionic strength was kept constant with only one electrolyte (using one of these salts: NaCl, KCl, MgCl₂ or CaCl₂), with binary mixtures of MgCl₂ and CaCl₂, and finally, in a solution with a composition approximately similar to that of natural seawater without sulfate. Equilibrium constants have been expressed in function of ionic strength by means of Pitzer equations and interaction parameters proposed in this theory have been obtained. It has been found that acid–base behaviour of TEA depends greatly on the salt used: basicity of TEA is decreased by CaCl₂, while it is increased by the other electrolytes used in this work.  相似文献   

Modelling the effect of swimbladder compression on the acoustic backscattering from herring at normal or near-normal dorsal incidences     

Gorska  Natalia; Ona  Egil 《ICES Journal of Marine Science》2003,60(6):1381-1391

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The target strength of Antarctic krill (Euphausia superba) measured by the split-beam method in a small tank at 70 kHz     

Amakasu  Kazuo; Furusawa  Masahiko 《ICES Journal of Marine Science》2006,63(1):36-45

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Relationship between acoustic backscattering strength and density of zooplankton in the sound-scattering layer   总被引：1，自引：0，他引：1  

Iida  Kohji; Mukai  Tohru; Hwang  DooJin 《ICES Journal of Marine Science》1996,53(2):507-512

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The acoustic target strength of herring (Clupea harengus L.) in the northern Baltic Sea   总被引：1，自引：0，他引：1  

Peltonen  Heikki; Balk  Helge 《ICES Journal of Marine Science》2005,62(4):803-808

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Comparing the modelled and measured target-strength variability of walleye pollock, Theragra chalcogramma     

Hazen  Elliott L.; Horne  John K. 《ICES Journal of Marine Science》2004,61(3):363-377

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New target-strength model indicates more krill in the Southern Ocean   总被引：5，自引：3，他引：5  

Demer  David A.; Conti  Stephane G. 《ICES Journal of Marine Science》2005,62(1):25-32

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