Organic Coatings on Sedimentary Mineral Grains

沉积矿物颗粒上的有机涂层

• 批准号: 9633230
• 负责人: Lawrence Mayer
• 金额: $ 40.71万
• 依托单位: University of Maine
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1996
• 资助国家: 美国
• 起止时间: 1996-10-01 至 2003-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9633230&HistoricalAwards=false
• 关键词: Organic; Coatings; Sedimentary; Mineral; Grains

9633230 Mayer A pore protection hypothesis will be tested, provide a mechanistic basis for the observed patterns of organic carbon. Relationships between organic matter and mineral surfaces will be developed by: (1) Assessing the extent of organic matter coverage on mineral grains. Is organic carbon localized in small areas or is it widely dispersed? Wide dispersal implies that major fraction must reside in small pores. This question will be tested by completing development of a promising new method based on the of gas adsorption onto mineral surfaces. Completion work will focus on the nature of naked mineral surfaces, identifying variations that derive from mineralogy, microtopography, and source area; (2) Determining if natural organic matter resides preferentially inside small mesopores, by careful examination of the effects of removal of organic coatings on the size distribution of pores. This test will also involve the reverse process of adding artificial organic coatings to uncoated mineral grains, providing insight into the localization and mechanism of organic matter sorption. (3) Testing if these small mesopores on mineral grains can indeed exclude hydrolytic enzymes, by performing a series of size- exclusion and adsorption experiments. These approaches will be carried out on a wide variety of sediments from around the world. In addition to testing the pore hypothesis, results from this project will have important implications for carbon cycling, mineral-water interactions, and pollutant cycling.

9633230 Mayer将测试孔隙保护假设，为观察到的有机碳模式提供机械基础。有机物与矿物表面之间的关系将通过：（1）评估矿物颗粒上有机物覆盖的程度。有机碳是否定位在小区域，还是广泛分散的？广泛的散布意味着主要部分必须居住在小毛孔中。 该问题将通过完成基于气体吸附到矿物表面的有希望的新方法来测试。 完成工作将集中在裸矿物表面的性质上，从而确定源自矿物学，微观图和源区域的变化； （2）通过仔细检查有机涂层对孔隙尺寸分布的影响，确定天然有机物是否优先驻留在小型中孔内。该测试还将涉及将人工有机涂层添加到未涂层的矿物谷物中的相反过程，从而深入了解有机物吸附的定位和机理。 （3）测试这些小中孔是否确实可以通过进行一系列大小排除和吸附实验来排除水解酶。 这些方法将在世界各地的各种沉积物上进行。除了测试孔假设外，该项目的结果还将对碳循环，矿物 - 水相互作用和污染物循环具有重要意义。