周期浅析     

战淑芸  杨淑瑞 《海洋预报》1992,9(4):47-51

本文分析了滑动平均的数据处理方法对周期分析结果产生的影响。提出了过程变量同号积分的数据处理方法,并对亚洲西风指数序列进行了试验分析。分析结果表明,周期的长短与振幅的大小有密切关系,亚洲逐日西风指数的周期振荡具有明显的季节特征。  相似文献   

Study of zooplankton ecology in Zhejiang coastal upwelling system-Zooplankton biomass and abundance of major groups   总被引：1，自引：0，他引：1  

He Dehu  Yang Guanming  Fang Shaojin  Shen Weilin  Liu Hongbin  Gao Aigen  Huang Shuxin 《海洋学报(英文版)》1988,7(4):607-620

The studied area is a shallow water area that belongs to the East China Sea continent shelf. The distribution of zooplankton biomass is higher inshore than offshore. The maximum abundance is in the inshore edge of the centre of upwelling, which is the superposed area of the salinity front and temperature front, due to the fact that the mixture of three different waters has brought about a concentration of nutrients. The herbivorous Euphausia, Copepoda and Tunicata are the major groups of the abundant area. Tunicata possess the possibility to compete against other kinds of herbivorous zooplankton. This means that there is negative correlation between the distribution of Tunicata and that of Copepoda and Euphausia. The positions of maximum areas of zooplankton biomass, phytoplankton individual and the concentration of phosphates and chlorophyll-a overlap one another. In the centre of upwelling, zooplankton can not adapt itself to the environment of lower temperature and less oxygen even with rich nutrient  相似文献   

Semi-Probabilistic Evaluation of System Redundancy for Existing Offshore Structures     

Zhang Shengkun Chen Kaisheng Mu Yang Professor 《中国海洋工程》1995,(1)

In this paper, a new definition of structure system redundancy is proposed in view of the various measures for structure redundancy. By introducing the terms of structure system failure at the mechanism level and equivalent reliability index, the safety for existing offshore platforms can be evaluated by the semi-probabilistic method presented in this paper. Some numerical examples are given and satisfactory results have been obtained.  相似文献   

Behavior of Pile Groups under Lateral Load   总被引：2，自引：0，他引：2  

Yang Keji  Li Qixin Wang Fuyuan Associate Proferssor  Hehai University  Nanjing Engineer  Hehai University  Nanjing 《中国海洋工程》1991,(2)

Based on investigation and model tests, and in combination with the research work on group effect for pile groups under lateral loads relating to the code of fixed offshore platforms, a series of studies have been performed on the behavior and failure mechanism of laterally loaded pile groups, critical pile spacing inducing group effect, lateral bearing capacity of pile groups and its main influence factors, the stress-strain relationship for single piles and pile groups and so on. Some new laws about non-uniformity of load distribution in the longitudinal direction of pile groups and load-deflection (p - y) curves for pile groups have been discovered, and an empirical formula is presented in order to remedy the defect of current calculating methods at home and abroad. These results can be used for reference in the design of pile foundation under lateral loads.  相似文献   

辽宁菊花岛海域沉积物中某些化学要素分布特征研究     

杨新梅  周义华 《海洋湖沼通报》1991,(1):29-34

菊花岛周围海域38个站表层沉积物的铁、锰、铝、钛、磷、有机质、氮、铜、锌、铅、镉、镍和汞等化学要素含量的Q型因子分析计算表明,本区可划分为三个化学元素沉积区:1.海流悬浮沉积区;2.近岸波浪作用区;3.波浪海流作用区。柱状沉积物中铁等化学元素的迁移、富集受氧化——还原界面的控制。  相似文献   

黄河口及其邻近海域营养盐分布特征     

陈淑珠  顾郁翘  刘敏光  张敏秀  杨淑海  李静 《中国海洋大学学报(自然科学版)》1991,(1)

1985年5、8月中法联合调查黄河口海域的营养盐,其样品采用常规的分光光度法测定。营养盐的分布总趋势是河口附近浓度高,外海浓度低,河口与外海浓度之比达数百倍。在河口及其邻近海域营养盐的分布梯度与盐度的分布一致。在河口控制营养盐含量的主要因素是河水和海水的混合过程。在119°30′～50′E,37°25′～38°5′N,PO_4—P,SiO_3—Si出现低值区。在此范围附近恰恰浮游植物的总量比较高。对8月份的02站进行了25h的连续观测,其结果是底层营养盐与盐度有良好的负相关性,而表层的相关性较差 黄河具有很高的氮磷比值,这很可能是农业上用氮肥量增多引起的。  相似文献   

An analysis on El Nino processes during 1949-1987     

Zhan Shuyun  Yang Shurui 《海洋学报(英文版)》1990,9(2):219-226

-In this paper, the outset, evolution and intensity of El Nino were analyzed. Different features were found in each El Nino process. The El Nino of 1986 was also analyzed and outlined.  相似文献   

西沙群岛的海草     

杨宗岱 《海洋科学集刊》1985,(24):119-124

海草在世界各海域已知有12个属,其中8个属在我国有分布。在从五十年代后期开始的西沙群岛动、植物区系调查中,先后采到海龟草 Thalassia hemprichii ( Ehrenb.) Aschers.、喜盐草 Halophila ovalis (R.Br.) Hook.和无横脉喜盐草 H. beccarii Aschers.等三种海草,分隶于二属。 海草是一个热带性较强的类群,在已知的12个属中,有7属以热带为分布中心。分布在我国沿海的8属海草中,也有6属是热带性的(包括西沙群岛的2属3种),其中海龟草是纯热带种类,而喜盐草和无横脉喜盐草是热带一亚热带类型。 在我国,有关海草的研究甚少,本文首次报道西沙群岛海草。海龟草、喜盐草及无横脉喜盐草均为我国新记录。  相似文献   

东亚和东南亚第四系时间界面的建议     

杨子赓  林和茂 《海洋地质与第四纪地质》1991,11(2):115-128

在东亚和东南亚第四系对比中,有关的几条界限,本文建议如后。采用Globorotalia truncatulinoides的初现位作为本区海相第四系的下界,其位置大致在古地磁Olduvai亚时的下界,时间约为距今1.9Ma。在南中国海、东海及沿岸地区,发现了以G.truncatulinoides的初现位为代表的一系列有意义的生物事件,如Pulleniatina finalis的初现位,Globigerinoides obliquus和Globoquadrina altispira的灭绝位,以及Globorotalia menardii和Pulleniatina obliquloculata壳体旋向的变化。此界限在东亚和东南亚也是相当稳定的。在陆相地层中,以泥河湾组为代表,狭义的泥河湾动物群(相当于晚维拉方动物群)所在地层的底界,其古地磁位置为Olduvai亚时的底界。以此作为陆相第四系的下界,与上述海相第四系底界一致。 以古地磁布容/松山界线作为中更新世和早更新世的界限,其年代为0.73MaB.P.。中国中更新世的标准地层周口店组,其底界恰为布容/松山的转换面,北京猿人的年代为0.60—0.23MaB.P.。在洛川黄土剖面上,布容/松山界线为古土壤S_7的底界。雷琼地区中更新统下部的北海组的底界也是布容/松山界线,所产的玻璃陨石的裂变径迹年龄为0.687—0.733MaB.P.。在黄海,布容/松山界线是第Ⅶ海侵层的顶界。通过岩石地层标志,以及动物群、古人  相似文献   

壳聚糖酶高产菌株的筛选和发酵条件的研究   总被引：6，自引：0，他引：6  

孙玉英  韩宝芹  刘万顺  张继泉  姚如永  彭睿 《中国海洋大学学报(自然科学版)》2007,37(2):266-272

从采集的土样中分离到1株产壳聚糖酶能力较强的菌株OU01,并对OU01进行了16S rDNA序列、形态及生理生化鉴定分析。16S rDNA序列分析表明该菌属于微杆菌属;该菌的形态特征与生理生化鉴定结果表明该菌与Microbacteriumsp.的相似性最高;因此将其初步鉴定为微杆菌属(Microbacterium)。同时对该菌的发酵条件进行了初步研究:该菌的最适培养基组成为(g/L):chitosan 10,(NH4)2SO420,MgSO4.7H2O 1.3,K2HPO4.3H2O 1.4,Glucose 1,Yeast extract 3,NaCl 5,起始pH=6.30。最适发酵温度为30℃,最佳发酵时间为96 h,在上述最优条件下,该菌株产酶达到118 U/mL。Microbacteri-umsp.OU01菌株为壳聚糖酶的研究和应用提供了新的来源。  相似文献