珠江口沉积物酸挥发性硫化物与重金属生物毒性的研究     

杨永强  陈繁荣  张德荣  张凌  吕莹 《热带海洋学报》2006,25(3):72-78

研究了2003年10月采于珠江口5个站位的沉积物剖面酸挥发性硫化物(AVS)和同时提取的重金属(SEM:Pb,Zn,Cu,Cd,Ni)。其中,站位1、2位于中滩,其沉积物的AVS含量变化范围较小,为0.25—4.06μmol.g-1;站位3、4位于西滩,其沉积物的AVS含量变化范围较大,为0—26.09μmol.g-1。中滩和西滩沉积物的AVS含量均随深度增加。西滩表层沉积物的AVS含量接近于零,这可能与该水域较强的底层流和沉积物的再悬浮作用有关。站位5位于珠江口外侧,其表层沉积物的AVS含量相对较高,且垂向变化较小,可能是还原性沉积物间歇性再悬浮后重新沉积的结果。站位1、2和5沉积物中同时提取的重金属含量大体在0.95±0.2μmol.g-1范围内,随深度增加略呈下降趋势;而西滩沉积物重金属含量相对较高,为1.43—2.42μmol.g-1,且在一定深度范围内随深度增加呈明显下降的趋势,表明珠江口西滩沉积物中的重金属污染有加重的趋势。对AVS/SEM摩尔比值和单个金属的毒性效应研究显示,珠江口内尤其是西滩的表层沉积物存在重金属污染,对其中生活的底栖生物具有潜在的毒性效应。  相似文献   

Environmental control of growth and BChl a expression in an aerobic anoxygenic phototrophic bacterium, Erythrobacter longus (DSMZ6997)   总被引：1，自引：0，他引：1  

LI Qiang  JIAO Nianzhi  PENG Zaiqing 《海洋学报(英文版)》2006,25(6):138-144

1Introduction Aerobic anoxygenic phototrophic bacteria(AAPB) are facultative heterotrophs that can utilizelight for photosynthesis. These unique-functioningbacteria are widely distributed in marine environ-ments, such as coastal waters (Shiba et al., 1991…  相似文献   

E1 Nio phenomenon in simple ocean data assimilation data     

GUI Maochang  *  WU Lingjuan  . Institute of Oceanology  Chinese Academy of Sciences  Qingdao  China. Laboratory of Numerical Modeling for Atmospheric Sciences  Geophysical Fluid Dynamics  Institute of Atmospheric Physics  Chine-se Academy of Sciences  Beijing  China. Graduate School  Chinese Academy of Sciences  Beijing  China 《海洋学报(英文版)》2005,(4)

1 IntroductionIt is well known that interaction between the trop-ical ocean and atmosphere produces the largest inter-annual climate signal, El Nino-Southern Oscillation(ENSO). In past decades many efforts have been madein understanding and predicting ENSO: such as the hy-pothesis of Bjerknes (1969) that ENSO arises as aself-sustained cycle in which SSTA in the Pacific O-cean causes the trade winds to strengthen or slackenand that this in turn drives the ocean circulation changesthat …  相似文献   

Numerical and experimental study on hydrodynamic interaction of side-by-side moored multiple vessels   总被引：2，自引：0，他引：2  

S.Y. Hong  J.H. Kim  S.K. Cho  Y.R. Choi  Y.S. Kim 《Ocean Engineering》2005,32(7):783-801

This paper aims to investigate the basic interaction characteristics of side-by-side moored vessels both numerically and experimentally. A higher-order boundary element method (HOBEM) combined with generalized mode approach is applied to analysis of motion and drift force of side-by-side moored multiple vessels (LNG FPSO, LNGC and shuttle tankers). Model tests were carried out for the same floating bodies investigated in the numerical study in regular and irregular waves. Global and local motion responses and drift forces of three vessels are compared with those of calculations. Discussions is highlighted on applicability of numerical method to prediction of sophisticated multi-body interaction problem of which motion behavior is very important to analysis of mooring dynamics of deep sea floating bodies.  相似文献   

Mechanical Characteristics of Light-Weighted Soils Using Dredged Materials     

Gil-Lim Yoonz  Sang-Soo Jeon  Byung-Tak Kim 《Marine Georesources & Geotechnology》2004,22(4):215-229

This study investigates the mechanical characteristics of light-weighted soils (LWS) consisting of expanded polystyrene (EPS), dredged clays, and cement through both unconfined and triaxial compression tests. The mechanical characteristics of the compressive strength of LWS are analyzed with varying initial water contents of dredged clays, EPS ratio, cement ratio, and curing pressure. In the triaxial compression test, it is found that the compressive strength of LWS associated with EPS is independent on the effective confining pressure. When both EPS ratio is less than 2% and cement ratio is more than 2%, the compressive strength rapidly decreases after the ultimate value. This signifies that the compressive strength-strain behavior is quite similar to that of the cemented soil. The ground improved by LWS has the compressive strength of 200 kPa associated with the optimized EPS ratio of 3-4% and initial water content of 165-175%. The ultimate compressive strength under both triaxial and unconfined compression tests is almost constant for a cement ratio of up to 2%.  相似文献   

海水中234Th的超低水平液闪谱仪测定   总被引：2，自引：1，他引：2  

李鸿宾  黄奕普  陈敏  刘广山  邱雨生 《台湾海峡》2004,23(2):199-207

本文提出了利用超低水平液闪谱仪测定海水中234Th的方法.海水经氢氧化铁吸附共沉淀富集后,接着用阴离子交换和TBP/煤油萃取进行Th同位素的分离与纯化.对一系列测定条件进行了详细的研究,提出了测定海水中234Th的适宜程序,即在含有234Th和产额示踪剂230Th的纯化后的5mol/dm3HNO3溶液中加入TBP/煤油进行萃取,然后用0.1mol/dm3HNO3反萃取,后者是先用契伦柯夫计数法测量234Th(通过234mPa),后加入闪烁液Hisafe 3用α/β模式测量α放射体230Th.对于α和β放射体液闪谱仪的计数效率分别为100%和55.7%±2.7%.234Th的化学回收率和总探测效率分别为70%～80%和30%～45%.该法测定海水中的234Th快速、简便和高效.  相似文献   

Freely floating-body simulation by a 2D fully nonlinear numerical wave tank     

Weoncheol Koo  Moo-Hyun Kim 《Ocean Engineering》2004,31(16):221-2046

Nonlinear interactions between large waves and freely floating bodies are investigated by a 2D fully nonlinear numerical wave tank (NWT). The fully nonlinear 2D NWT is developed based on the potential theory, MEL/material-node time-marching approach, and boundary element method (BEM). A robust and stable 4th-order Runge–Kutta fully updated time-integration scheme is used with regriding (every time step) and smoothing (every five steps). A special φ_n-η type numerical beach on the free surface is developed to minimize wave reflection from end-wall and wave maker. The acceleration-potential formulation and direct mode-decomposition method are used for calculating the time derivative of velocity potential. The indirect mode-decomposition method is also independently developed for cross-checking. The present fully nonlinear simulations for a 2D freely floating barge are compared with the corresponding linear results, Nojiri and Murayama’s (Trans. West-Jpn. Soc. Nav. Archit. 51 (1975)) experimental results, and Tanizawa and Minami’s (Abstract for the 6th Symposium on Nonlinear and Free-surface Flow, 1998) fully nonlinear simulation results. It is shown that the fully nonlinear results converge to the corresponding linear results as incident wave heights decrease. A noticeable discrepancy between linear and fully nonlinear simulations is observed near the resonance area, where the second and third harmonic sway forces are even bigger than the first harmonic component causing highly nonlinear features in sway time series. The surprisingly large second harmonic heave forces in short waves are also successfully reproduced. The fully updated time-marching scheme is found to be much more robust than the frozen-coefficient method in fully nonlinear simulations with floating bodies. To compare the role of free-surface and body-surface nonlinearities, the body-nonlinear-only case with linearized free-surface condition was separately developed and simulated.  相似文献   

南海南部粉红色 Globigerinoides ruber 冰期旋回及影响因素     

徐建  翦知湣 《海洋地质与第四纪地质》2003,23(4):59-64

对南海南部ODP1143站氧同位素11-5e期大约2ka分辨率的粉红色Globigerinoides ruber进行分析,发现其冰期／间冰期旋回与代表全球冰量的底栖有孔虫氧同位素(δ^18O)的变化相反,即在间冰期时含量低,而冰期时高,与其他海区的记录相反。海水表层温度和温跃层深度转换函数结果以及碎壳率的变化显示,在一定的温度背景下,温跃层深度的变化可能是控制粉红色G．ruber冰期旋回的主要因素,而这段时期南海南部溶解作用的影响则不明显。  相似文献   

合浦珠母贝26S蛋白酶体S4,S7亚基基因片段的分离与分析     

姜铁民  张勇  黄洁  谢莉萍  吴移谋  张荣庆 《海洋科学》2003,27(4):28-34

26S蛋白酶体是真核生物中一种具有ATP依赖性的蛋白酶复合体,主要通过泛肽途径选择性降解细胞内与代谢调控、细胞周期有关的功能蛋白及异常蛋白,参与多种细胞活动的调控过程。26S蛋白酶体由具有催化活性的20S亚复合体和一个具有调节作用的19S亚复合体组成,其中19S亚复合体中的ATP酶亚基是调节26S蛋白酶体活性的重要组件。本通过简并引物PCR手段,从软体动物合浦珠母贝(Pinctada fucata)中扩增到参与构成19S亚复合体的S4和S7(MSS1)两个亚基的基因片段。这两个基因片段所编码的ATP酶组件包含有Gx4GKT,DEID,SAT和H／QRxGRxxR等26S蛋白酶体ATP酶亚基的共同功能基序。这是首次在软体动物中报道26S蛋白酶体的ATP酶亚基基因序列,为研究软体动物中26S蛋白酶体的结构与功能奠定了分子基础。  相似文献   

固定化鲅鱼乙酰胆碱酯酶的制备及部分性质测定   总被引：3，自引：0，他引：3  

孟范平  何东海  朱小山  马冬冬  杨正先  YANG Zheng-Xian 《中国海洋大学学报(自然科学版)》2005,35(6):1067-1071

酶的固定化是酶传感器制备过程中重要的1个环节.研究采用直接共价法固定鲅鱼乙酰胆碱酯酶（AChE）.制备方法为：0.1g CNBr活化的Sepharose 4B凝胶用1mmol/L的HCl充分溶胀后,与活力为10U的AChE溶液混合,于4℃下150r/min振荡8h.所制备的固定化酶活力回收率较高（96%）,对pH值和温度变化的适应能力均优于非固定化酶;在3个月保存期内,前者的活力损失13%,而后者的活力则下降89%.这说明固定过程能够大大提高AChE的抗逆性和保持酶活力的稳定,有利于酶传感器的制备.  相似文献