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开发绿色环保防污剂是海洋船舶防污涂料研究的重要方向,查明防污活性化合物分子结构中的防污活性基团,是设计开发新型防污剂的关键。本文合成了三种结构相似的苯酰胺类化合物HNOB、DOLPA和DHNOB,通过FTIR,1H NMR,13C NMR测试表征三种化合物的分子结构,利用典型污损生物硅藻和贻贝作为目标生物,测试其对硅藻和贻贝附着的影响,并将分子结构与防污活性进行对比,初步探讨影响防污性能的活性基团。硅藻和贻贝附着实验均表明,HNOB的防污性能较好,半数抑制浓度远低于DOLPA和DHNOB。通过结构对比分析发现,极性和非极性结构的协同作用比单一的极性基团或非极性长碳链基团能更好地赋予苯酰胺类物质良好的防污性能。该研究初步探讨了苯酰胺类化合物的构效关系,有助于新型防污活性化合物的设计开发和结构优化,并对探究该类化合物防除污损生物附着的机理和快速筛选有潜力的防污化合物具有重要意义。  相似文献   
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胞外多聚物(extracellular polymeric substance, EPS)是海洋底栖硅藻在水下表面附着时分泌的物质,环境因素对胞外多聚物的组成和分泌行为有直接影响,本文重点探讨了氧含量和附着面积对胞外多聚物的影响。采用热溶剂浸提法提取硅藻胞外多聚物,利用苯酚-硫酸法定量其中的多糖成分,利用考马斯亮蓝G-250法定量蛋白质成分,通过血球计数板法和紫外分光光度法计算细胞数量。结果表明,在氧含量高、可附着面积大的条件下,硅藻的生长繁殖速率快,且单个细胞的胞外多聚物分泌量大。氧含量对胞外多聚物主要成分中的水溶性多糖含量影响大,而对其余成分含量影响小。可附着面积对硅藻附着和生长的影响比氧含量影响小。  相似文献   
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Serious soil erosion has already resulted in degradation of the Loess Plateau of China. Soil erosion is commonly accompanied by extensive soil nutrient loss. Because of enrichment processes,sediment nutrient content is often higher than that of natural soil. The objective of this study is to determine the enrichments of organic matter and total nitrogen in sediment in hilly and gully loess areas on the Loess Plateau of China. Measurements of enrichment ratios (ER) of organic matter (EROM) and total nitrogen (ERTN) in sediment as affected by rainfall, slope gradient, tillage, and fertilization were made in the field under natural rainfall conditions. The results showed that the enrichment of clay in sediment resulted in the enrichment of organic matter (OM) and total nitrogen(TN) in sediment. The averages of sediment clay ER, EROM and ERTN for the various slope gradients were 1.77, 2.09 and 1.61, respectively. The soil erosive module was negatively correlated with EROM and ERTN. Our results indicate that measures to reduce soil erosion, i.e. reducing rainfall erosivity, decreasing soil slope gradient, decreasing fertilizer use, and using level trenches, may increase EROM and ERTN. Both quantity and quality of sediment yield should be considered when implementing erosion control measures.  相似文献   
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