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611.
In the presence of biofilms, stainless steels(SS) exhibits an increase in corrosion potential, called ennoblement. In the present study, the corrosion potential(Ecorr) behavior of the duplex SS UNS S32760 was recorded simultaneously with the in situ marine biofilm formation in two areas at Arraial do Cabo,Southeastern Brazil. The biofilm at Forno Harbor(an anthropogenically disturbed area) was characterized by higher relative abundances of Bacteria at day 2, followed by diatoms(especially Navicula sp.) on day 10 and dinoflagellates on day 18,whereas no clear trend was recorded at Cabo Frio Island(an undisturbed area). The ennoblement of Ecorr values was site-dependent. In a complementary laboratory assay, biofilms were removed and the Ecorr values registered in sterile conditions for the subsequent 10 days and corroborated in situ results. Understanding biofilms and SS interactions has important implications for materials science and engineering decisions as well as helping to fill in important gaps in this knowledge. 相似文献
612.
文中通过FSA方法,分析构成海事事故的危险因素,提出实际有效的风险控制措施,基于有效性和经济性评估风险控制方案,从而得到最后的选择结果,完成本次基于FSA的秦皇岛港通航安全的研究。 相似文献
613.
Hui Ding Haigen Xu Jun Wu W. J. F. Le Quesne C. J. Sweeting N. V. C. Polunin 《Coastal management》2013,41(5):443-457
Marine ecosystems of the East China Sea are rich in biodiversity, with 12,933 species of which approximately 47.7% are endemic. As anthropogenic impacts are intensifying, fishery resources and biodiversity in the East China Sea are under threat from overfishing, habitat loss, pollution, and biological invasions. Marine protected areas (MPAs) and other spatial management measures are believed useful tools to protect and restore biological resources. Seventeen nature reserves, seven special marine reserves, and three fishery resource conservation zones covering a combined area of 102,156 km2 have so far been established in the Chinese East China Sea in order to protect fishery resources, biodiversity, and marine landscapes. This article provides a review and inventory of MPAs in the Chinese East China Sea as implemented by the People's Republic of China. 相似文献
614.
发展海洋渔业可以缓解国家粮食安全压力,拓宽中国海洋渔业发展空间,维护国家海洋权益。专业化渔业物流船队是保障和支撑海洋渔业发展的重要组成部分,文章从不同的服务对象角度对渔业物流船队进行了划分,详细介绍了各类型渔业物流船队的发展历程、主要做法和取得的成效,指出了我国的渔业物流船船龄大,装备陈旧,自动化程度低和信息化水平弱等严重制约我国渔业物流船队发展的问题,提出了全面推进渔业物流船队的专业化建设、推动渔业物流船装备自动化革新、提升渔业物流船的信息化水平等实现渔业现代化的经验启示。 相似文献
615.
616.
Cod (Gadus morhua) inhabit not only the famous fishing banks of the Northwest Atlantic continental shelf, but also inshore waters from Labrador to New England. Relatively little is known about the life history of inshore cod, their historic levels of abundance, and their relationship to offshore stocks. Inshore cod stocks along the East Coast should be managed under a new paradigm that recognizes the importance of these fish to the stock complex. Recently documented fishers' ecological knowledge (FEK) suggests inshore stocks of cod may exist along the Newfoundland and Labrador coastline that have yet to be scientifically documented. Coastal communities adjacent to the local population of cod in Gilbert Bay, Labrador have initiated efforts to protect and manage this stock locally through a co-management approach. The Gilbert Bay experience, FEK, and related science and education could provide insight into ways to protect and enhance the health of local stocks remaining along the northeast coast of North America. 相似文献
617.
Competing interests related to marine resources have the potential to create conflict in the coastal zone. In many parts of the world marine farms exist in close proximity to areas that support recreation and tourism. The purpose of this study was to examine residents’ perceptions of proposed marine farm development related to their proximity to, and recreational use of, a coastal area in New Zealand. Residents from two areas were surveyed about their recreational use of the region and about perceptions related to marine farm development. Results indicated that those living closest to proposed marine farms used the area more often and in different ways, were most sensitive to marine farm development, and were less positive in their evaluations of marine farms, despite agreeing that marine farms can have positive economic consequences for nearby communities. Implications for using stakeholder input for the planning and management of marine farms are discussed. 相似文献
618.
为了解PTC群桩的施工对连云港软土具体的扰动规律,掌握其桩间海相软土孔隙水压力的积累和消散、软土强度变化特征,进行了现场PTC管桩群桩沉桩现场试验研究,得到了一系列有益的结论,将对其设计、施工起一定的指导作用。 相似文献
619.
介绍了基于工作流与数据库技术管理的大型船用低速柴油机台架试验及试航管理系统,主要对船用柴油机生产过程中设计与运行参数进行管理.系统主要由基础信息子系统、试车管理子系统、技术服务支持子系统、试车故障诊断子系统和标准管理子系统组成,具有信息共享、性能分析、排放计算、异常报警、试验数据管理和报表输出等功能. 相似文献
620.
随着船舶压缩制冷装置的集成化程度和自动化程度的不断提高,如何减少装置在使用过程中故障的发生并提高排除故障的效率,成为轮机管理工作迫切需要解决的课题。本文结合领域专家的经验和先进的计算机编程技术,提出了船舶制冷装置故障诊断专家的设计思路。借此以提高故障诊断的效率,并提供维修建议。 相似文献