海洋工程用新型牺牲阳极设计与性能研究(Ⅳ)——导管架平台阴极保护应用研究

目的通过构型优化设计了一种新型牺牲阳极,使其在与常规阳极质量相当的前提下,增加初期发生电流,使被保护体较快极化到保护电位,后期发生电流降低,满足平均和末期保护电流需要,达到节约牺牲阳极用量的目的。方法在传统梯形阳极两侧增加两个翼翅,降低接水电阻,增加初期发生电流。翼翅优于本体快速溶解,其表面积迅速减小,发生电流随之降低。结果质量与常规阳极相近的新型阳极,初期发生电流增加30%以上,远高于设计值10%,初期极化完成后,新型阳极发生电流快速降低,达到与常规阳极相当的发生电流。结论据此试验结果对导管架平台水下结构进行阴极保护设计,可达到节约牺牲阳极用量的目的。     

热带海洋环境中5083铝合金腐蚀行为研究

目的 研究某岛礁不同海洋区带环境中5083铝合金的腐蚀规律。方法 在某岛礁进行海洋多区带腐蚀试验,利用表面微观形貌观测、腐蚀产物分析、质量损失测试及点蚀深度测量等手段,对比分析铝合金在不同海洋区带中的腐蚀形貌、腐蚀速率和点蚀深度。结果 5083铝合金在某岛礁海洋全浸区带环境中的腐蚀速率最大,大气区带中的腐蚀速率最小,在潮差区带的腐蚀速率介于二者之间。试样在海洋不同区带主要发生局部腐蚀,大气区试样的最大点蚀深度最大,而潮差区试样的最大点蚀深度最小。在不同海洋区带,铝合金腐蚀产物和附着物的混合物中均含有钙元素,大气区钙元素含量远低于潮差区和全浸区,潮差区和全浸区铝合金表面的腐蚀产物和附着物混合物中主要含有CaCO₃、CaSiO₃和Al₂O₃。结论 不同海洋区带环境中,5083铝合金的腐蚀速率差别较大,潮差区和全浸区材料表面附着大量污损生物和矿物质。     

雷达吸波涂层海洋大气环境适用性试验研究

目的 分析一种雷达吸波隐身涂层在海洋大气自然环境下性能的变化规律。方法 对12个月不同阶段涂层的常规物理性能和电性能进行检测,其中常规物理性能包括宏观形貌、金相形貌、微观性能、附着力、抗冲击强度和红外光谱。结果 从宏观形貌看,涂层明度和色差值呈上升趋势,12个月明度增加1.22,色差值增加2.91,颜色向绿色和蓝色发展,失光率先增大、后减小,最大失光率为9个月时的34%。涂层附着力和试验时间呈现非线性关系,6个月时,附着力降低了18%,12个月时增大了24%。涂层在2～18GHz的频率范围内,吸波曲线大体呈“U”形,最低反射率随时间向低频方向偏移。涂层金相形貌、微观性能、抗冲击强度和红外光谱特征总体变化不明显。结论 在1a内,自然海洋大气环境对雷达吸波隐身涂层常规物理性能和电性能产生了一定影响,但在试验时间相对较短情况下,海洋大气环境对涂层老化的影响作用尚未充分显示,需要结合更长周期的试验数据进一步分析。     

Assessing the current state of ecological connectivity in a large marine protected area system

The establishment of marine protected areas (MPAs) is a critical step in ensuring the continued persistence of marine biodiversity. Although the area protected in MPAs is growing, the movement of individuals (or larvae) among MPAs, termed connectivity, has only recently been included as an objective of many MPAs. As such, assessing connectivity is often neglected or oversimplified in the planning process. For promoting population persistence, it is important to ensure that protected areas in a system are functionally connected through dispersal or adult movement. We devised a multi-species model of larval dispersal for the Australian marine environment to evaluate how much local scale connectivity is protected in MPAs and determine whether the extensive system of MPAs truly functions as a network. We focused on non-migratory species with simplified larval behaviors (i.e., passive larval dispersal) (e.g., no explicit vertical migration) as an illustration. Of all the MPAs analyzed (approximately 2.7 million km²), outside the Great Barrier Reef and Ningaloo Reef, <50% of MPAs (46-80% of total MPA area depending on the species considered) were functionally connected. Our results suggest that Australia's MPA system cannot be referred to as a single network, but rather a collection of numerous smaller networks delineated by natural breaks in the connectivity of reef habitat. Depending on the dispersal capacity of the taxa of interest, there may be between 25 and 47 individual ecological networks distributed across the Australian marine environment. The need to first assess the underlying natural connectivity of a study system prior to implementing new MPAs represents a key research priority for strategically enlarging MPA networks. Our findings highlight the benefits of integrating multi-species connectivity into conservation planning to identify opportunities to better incorporate connectivity into the design of MPA systems and thus to increase their capacity to support long-term, sustainable biodiversity outcomes.     

Biodegradation of N,N-bis(carboxymethyl)-L-glutamate and its utilization as sole source of carbon,nitrogen, and energy by a Rhizobium radiobacter strain in seawater

Biodegradation of N,N-bis(carboxymethyl)-L-glutamate and its utilization by micro-organisms in marine environments were studied in Organization of Economic Development and Cooperation (OECD) screening tests and with pure bacterial cultures. Biodegradation in excess of 60% was achieved in closed bottle tests in less than 60 days, suggesting complete degradation. The bacterial strain isolated from marine sandy sediment and utilizing N,N-bis(carboxymethyl)-L-glutamate as sole source of carbon, nitrogen, and energy was identified as Rhizobium radiobacter. The strain was capable to mineralize N,N-bis(carboxymethyl)-L-glutamate in seawater and in synthetic media containing 0–60 g L^?1 sea salts. Growth and adaptation studies indicated that N-carboxymethyl-L-glutamate and L-glutamate are main metabolites.     

北部湾涠洲岛原油污染物的海水环境质量基准研究

选择9种我国本土海洋生物对北部湾涠洲岛原油污染物的急性生物毒性进行测试,并基于测试获得的毒性数据,利用美国水生生物基准推算方法,对该原油污染物的海水环境基准阈值进行推导,结果表明:原油样品对卤虫、褶皱臂尾轮虫、太平洋纺锤水蚤、中国对虾、三疣梭子蟹、彩虹明樱蛤、牙鲆、半滑舌鳎、青岛大扁藻的LC50(或EC50)分别为10.28, 2.37, 4.88, 0.31, 0.81, 65.88, 19.02, 9.10, 0.23mg/L;涠洲岛原油污染物的急性和慢性海水质量基准阈值分别为0.06,0.012mg/L.研究结果可为我国海上溢油事故损害评估提供科学依据.     

Determination of polychlorinated biphenyl and polycyclic aromatic hydrocarbon marine regional Sediment Quality Guidelines within the European Water Framework Directive

Marine regional Sediment Quality Guidelines (SQG) for polychlorinated biphenyls (PCB) and polycyclic aromatic hydrocarbons (PAH) from the Basque coast (SE Bay of Biscay) were determined, on the basis of sediment chemistry, toxicity and benthic community disturbance from analysis of 756 estuarine and coastal samples. The SQG were calculated using a percentile approach (based upon effect and non-effect data), using non-normalised and normalised concentration, by total organic carbon. However, normalisation by total organic carbon did not result in any improvement in accuracy compared with non-normalised values. Hence, this study proposes non-normalised SQG values for assessment of the chemical and physicochemical status in marine waters in the Basque Country, within the Water Framework Directive: 24.6–29 μg kg^?1 for total PCBs; 164–285 μg kg^?1 for low molecular weight PAH; 922–1537 μg kg^?1 for high molecular weight PAH; and 1607–2617 μg kg^?1 for total PAH.     

汞在海洋浮游植物中的生物累积和毒性效应

浮游植物是海洋生态系统的主要初级生产者,同时作为食物也是许多水生生物摄取汞的主要途径。本文综述了近年来汞在海洋浮游植物中的最新研究进展,包括汞在浮游植物中的吸收、累积规律及其影响因素,汞对浮游植物的毒性效应(生长抑制、光合作用影响)以及生物的适应机制(汞的还原、螯合解毒、矿化固定等),最后对浮游植物中汞累积和毒性的未来研究方向进行了展望。     

海洋环境中纳米金属的生物吸收及生物效应

当前随着纳米科技的发展,纳米材料,特别是纳米金属,因其独特的物化性质,在各行各业中的使用量呈指数增长,致使其在大气、水域、土壤环境中的安全性问题引起公众关注。尤其是在受到人类活动密切影响的近岸海洋环境中,纳米金属的潜在生态效应成为当前国内外研究的热点之一。本文重点综述了由于海洋环境的理化因子以及纳米金属独特的物化性质导致的纳米金属的环境行为,海洋生物对纳米金属的吸收,以及纳米金属的生物效应和可能的致毒机制,旨在为评估海洋环境中纳米金属的潜在生态危害,完善纳米材料的监管机制及保障纳米科技的可持续发展提供思路。     

石油污染对海洋生态环境的影响与防治对策

分析了石油污染对海洋生态环境的影响,提出了预防泄漏措施.