强壮箭虫对温度、盐度的耐受性研究

研究强壮箭虫对突变温度、突变盐度和渐变温度、渐变盐度的耐受性.结果表明:水温由15℃突变到1℃时,存活率为75%;水温由15℃突变为30℃时,存活率仅为5%.求得24h急性半致死温度上限为27.2℃.水温从20℃逐渐上升至25、30、35℃,存活率分别为85 %、10 %、0 %;水温从20℃逐渐下降至15、10、5℃,其存活率分别为 100 %、95 %和80 %.盐度从31突变为20、40,箭虫的存活率均为100%,随着盐度突变幅度的增大,强壮箭虫的存活率呈降低趋势.求得24h急性半致死盐度上限为45,24h急性半致死盐度下限为13.3.盐度逐渐从31上升到46、 52,其存活率由90%下降到0%;盐度逐渐从31降到13、6,其存活率由95%下降到0%.求得间隔12h半致死渐变盐度上限为48.7,半致死渐变盐度下限为9.3.根据实验结果,强壮箭虫应属喜冷广温种和近岸广盐种.     

Optimum design of filament-wound multilayer-sandwich submersible pressure hulls

Submersible pressure hulls with fiber-reinforced multilayer-sandwich constructions have been developed in recent years as substitutes for classical metallic ring-stiffened pressure hulls. This study aims to optimize the design of filament-wound multilayer-sandwich submersible pressure hulls, taking into consideration the shell buckling strength constraint, the angle-ply laminated facing failure strength constraint and the low-density isotropic core yielding strength constraint under hydrostatic pressure using the hybrid genetic algorithm (HGA). The thickness of the facing, the thickness of the core layer, the orientation angle of the fibers in the facings and the shear modulus of the core material are taken as design variables. A sensitivity analysis is performed to study the effects of the operational depths and the hull shell geometry parameter, the length-to-diameter ratio (L/D), on the optimal design of filament-wound multilayer-sandwich submersible pressure hulls with graphite/epoxy, glass/epoxy and boron/epoxy composite facings. The results reveal that the optimal weight of various sandwich pressure hulls increases linearly with the operational depth, but it is almost unchanged as the geometry paramter. Furthermore, Graphite/Epoxy is the best choice for the material of the facings in a light-weight design. With reference to wall design, Boron/Epoxy is the best choice for the material of the facing at shallow depths, but Graphite/Epoxy is the best choice at extreme depths. Results of this study provide a valuable reference for designers of underwater vehicles.     

赤潮叉角藻18SrDNA和ITS区序列测定与分析

采用PCR及克隆测序的方法，对1998年引发渤海赤潮的叉角藻18SrRNAadldey DNAITS区（Internal Transcribed Spacer Regions)进行了序列测定与分析。并通过因特网从国际分子生物学数据库中获取甲藻另外15个种的18rDNA序列，以Tetrahymena corlissi作为类群，分别采用Neighbor-Joining和Fitch方法构建甲藻较为一致和可靠的进化树图，探讨具有高度多样性和在分类上争议较多的甲藻各类群之间的形态与分子进化关系。结果表明，Prorocentrum(有2个简单的壳板）出现得较早，而大多数多甲藻目（覆盖着多个壳板）、裸甲藻目（大多数不具壳板）和膝沟藻目的成员较晚出现。另外，对叉角藻ITS区的分析表明，ITS区为高变区，是良好的分子标记，可用于叉角藻快速鉴定的专一性核酸分子探针的研制。     

东太平洋沉积物U的地球化学

本文对地矿部“海洋四号”科学考察船１９８７－１９８９年在东赤道太平洋ＣＣ区所取得的２７个深海表层沉积样品进行Ｕ的地球化学分析，探讨了Ｕ在深海沉积中的地球化学行为，结果表明，不同类型沉积的Ｕ含量不同，平均值由大至小的次序的含沸石粘土（２．１６×１０＾－６），硅质粘土（１．９５×１０＾－６），硅质软泥（１．６５×１０＾－６），钙质硅质粘土（１．５９×１０＾－６），在同类型沉积中Ｕ的分散性较大；Ｕ在区域     

匙指虾三新种记述

匙指虾除少数为大型个体外，多数均为体长仅20-30mm的小型淡水虾类。在中国已报道有7属100多种。在检查多年来从全国各地收集的匙指虾标本中，发现有三个新种，现报道如下。     

“916”低聚糖抗卵磷脂氧化活性的研究

作者采用自由基引发氧化模型。通过测定卵磷脂氢过氧化物 ( PCOOH) ,研究了“916”低聚糖对卵磷脂 ( PC)氧化的抑制作用。实验结果表明 :( 1)“916”低聚糖具有良好的抗氧化活性 ;( 2 )各低聚糖在质量相同和含硫量大致相同的条件下 ,总体上分子量越小抗氧化活性越高。     

近海污损生物的调查方法

近海海区污损生物调查有浮标挂板法和海上设施（浮标及其锚碇系统，Ｍａｒｅｘ水文浮标，移动式钻井平台和固定式生产平台）采样法。由于近海海区污损生物调查工作的特殊性和艰难性，笔者提出了利用已有的海上设施，尤其是固定式平台来积累近海污损生物资料，以便进行生态学研究。     

Study on Key Technology of Using Shell Sand as Backfill for Sea Reclamation

1 .IntroductionEpicontinental sea or land could formfromcontinental shelf because of the decreasing sea levelduring Quaternary.There is a large-area shell sand deposit more than ten meters thick in the neriticzone of China .To use the abundant marine shell sandresource as engineering material for ocean engi-neering and port engineeringis veryimportant .Sand (Gred and Bjorn,1999) ,fine sand (Zhangetal .,2002) , mediumand coarse sand (Qiuet al .,1995) ,highly weathered stone ballast (Zhanetal…     

氮浓度对四株海洋绿藻总脂含量和脂肪酸组成的影响

本文用NaNO3作为氮源,分别作了氮浓度的五个水平对2属(小球藻属、裂丝藻属)的四株绿藻的生长率、总脂含量及主要脂肪酸组成的影响。C19、C97和C102的脂肪含量随N浓度的改变而有较大变化,其中C102在1.6m mol/L时脂肪含量达到最大值(24.8%)。C95的脂肪含量随氮浓度变化不大。同时,由氮浓度引起的平均生长率μ与总脂含量之间无明显相关关系。四株绿藻的EPA(20∶5n-3)和PUFAs(polyunsaturated fatty acids)含量随培养基中氮浓度的改变有较大变化但因种而异。C95和C97均在中等氮浓度时EPA含量达到最大值,分别为23.8%和27.4%。C19和C102在高氮浓度(40mmol/L)获得EPA的最大值,分别为25.7%和26.6%。