N,N-二烷基酰胺类物质的膜状态及其在水面溢油集油剂中的应用研究

合成了 5种 N,N-二烷基酰胺型表面活性剂 ,并对其所成膜的状态进行了测定。表明当N,N-二烷基酰胺类物质单独成膜时获得的集油膜为多层膜 ,而当选用合适的溶剂与其配制成溶液以后 ,所成的集油膜则为转变膜或液态凝聚膜。在 5种 N,N-二烷基酰胺类物质中 ,酰基碳链越长、氮烷基碳链越短则其集油能力越强。应用 N,N-二烷基酰胺类物质配制了 4个配方 ,均具备良好的集油能力 ,并且对原油的集油能力大于对柴油的集油能力     

Evaluation of long-term extreme response statistics of jack-up platforms

This paper is concerned with the models appropriate for the dynamic assessment of jack-ups, concentrating particularly on the long-term response due to random ocean waves and on work-hardening plasticity models used for spud-can response. A methodology for scaling of short-term statistics, calculated using a Constrained NewWave technique, is shown in a numerical experiment for an example jack-up and central North Sea location. The difference in long-term extreme response statistics due to various footing assumptions is emphasised. Results for two environmental load conditions are described (one excluding and one including wind and current effects) and the role of sea-state severity in the variation of short-term extreme response statistics is also highlighted.     

Variability in oceanographic and ecological processes in the Canadian Arctic Archipelago

This paper brings together unpublished historical data sets and published literature to review the role of climatic, oceanographic and ecological processes in the marine ecosystem of the eastern Canadian Archipelago. Physical data include characteristics of the water masses, circulation patterns, sea ice conditions, and climatic records from 1950s onward. Biological data include unpublished data sets on nutrients, primary and secondary production, and sedimentation, which were collected during the 1980–1990s in the eastern Canadian Archipelago. These results show high year-to-year variability in nutrient inventories and ratios, the magnitude of the ice algae and phytoplankton bloom, the timing of ice algae sedimentation in the spring, and the composition of the zooplankton community. The significance of this high interannual variability and its effect on pelagic–benthic coupling processes is discussed in the context of climatic and oceanographic forcing, with emphasis on recent (past decade) Arctic changes. An estimate of total primary production in the Archipelago is also presented, along with published production estimates for other Arctic shelves, showing that the Archipelago may support up to 32% of the total primary production of Arctic shelves. The high year-to-year variability in production and carbon transfer pathways (e.g. pelagic versus benthic) in the Archipelago suggest that the system might be resilient to the increased variability in climatic conditions occurring in the past decade. However, this increased variability combined with directional change in climatic and oceanographic conditions might also modify the existing balance of ecological processes. For example, shifts in the timing of events appear to have already occurred in the past decade, with potential cascading effects throughout the ecosystem.     

The dynamics of the carbon cycle in the surface water of the Norwegian Sea

Historical data of total dissolved inorganic carbon (C_T), together with nitrate and phosphate, have been used to model the evolution of these constituents over the year in the Atlantic water of the Norwegian Sea. Changes in nutrient concentration in the upper layer of the ocean are largely related to biological activity, but vertical mixing with the underlying water will also have an impact. A mixing factor is estimated and used to compute the entrainment of these constituents into the surface water from below. After taking the mixing contribution into account, the resulting nutrient concentration changes are attributed to biological production or decay. The results of the model show that the change in C_T by vertical mixing and by biological activity based on nutrient equivalents needs another sink to balance the carbon budget. It cannot be the atmosphere as the surface water is undersaturated with respect to carbon dioxide and is, thus, a source of C_T in this region. Inasmuch as the peak deficit of carbon is more than a month later than for the nutrients, the most plausible explanation is that other nitrogen and phosphate sources than the inorganic salts are used together with dissolved inorganic carbon during this period. As nitrate and phosphate show a similar trend, it is unlikely that the explanation is the use of ammonia or nitrogen fixation but rather dissolved organic nitrogen and phosphate, while dissolved organic carbon is accumulating in the water.     

用贝叶斯方法推算设计波高

采用长期概率预报提供波浪要素设计值是海洋工程中不可缺少的内容之一，文中介绍了一种基於贝叶斯原理的新计算方法，它较传统统计方法有明显的优越性，不仅可以通过补充新信息不断修正原有的估算结果，而且可以避免传统方法带来诸多不确定性，文中以北海中部百年一遇设计波高为例进行了计算。     

粘土矿物去除赤潮生物的动力学研究

于１９９２年４－９月进行粘土矿的絮凝赤潮生物（微型原甲藻）的动力学研究；考察粘土种类、浓度、第二组分（ＰＡＣＳ）和ＰＨ等因素对絮凝速率的影响，建立粘土矿物絮凝赤潮生物的动力学模型，从理论上分析和讨论各种因素的影响，并提出提高絮凝速率的方法和途径。结果表明，高岭土体系絮凝速率大于蒙脱土体系，其速率方程可用双分子反应来描述。其中，速率常数随絮凝过程发生变化；粒子间的相互作用能和作用半径是控制和影响絮凝