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| 1 | Understanding the sources and composition of the incremental excess of fine particles across multiple sampling locations in one air shed显示文摘Well-designed health studies and the development of effective regulatory policies need to rely on an understanding of the incremental differences in particulate matter concentrations and their sources. Although only a limited number of studies have been conducted to examine spatial differences in sources to particulate matter within an air shed, routine monitoring data can be used to better understand these differences. Measurements from the US EPA Chemical Speciation Network(CSN) collected between 2002–2008 were analyzed to demonstrate the utility of regulatory data across three sites located within 100 km of each other. Trends in concentrations, source contribution, and incremental excesses across three sites were investigated using the Positive Matrix Factorization model. Similar yearly trends in chemical composition were observed across all sites, however, excesses of organic matter and elemental carbon were observed in the urban center that originated from local emissions of mobile sources and biomass burning. Secondary sulfate and secondary nitrate constituted over half of the PM2.5with no spatial differences observed across sites. For these components, the excess of emissions from industrial sources could be directly quantified. This study demonstrates that CSN data from multiple sites can be successfully used to derive consistent source profiles and source contributions for regional pollution, and that CSN data can be used to quantify incremental differences in source contributions of across these sites. The analysis strategy can be used in other regions of the world to take advantage of existing ambient particulate matter monitoring data to better the understanding of spatial differences in source contributions within a given air shed. | Jerome E.McGinnis Jongbae Heo Michael R.Olson Andrew P.Rutter James J.Schauer | 2014 | Journal of Environmental Sciences2014，26，4： | 1 |
| 2 | Consumerperceptions of product quality:made in china显示文摘 | SCHN IEDERJANSM J QING CAOJOHN R.OLSON | | 0，，： | 1 |
| 3 | 估计土壤流失量的方法显示文摘为了定量侵蚀引起的土壤流失程度,建立了一个新的x射线光谱法。按顶土厚度,或者粘粒含量最大层顶,或者粘化层顶估计的方法对加速侵蚀引起的土壤流失量的估计偏低.被测的每一土壤有一特殊的质量吸收系数(μM)线,并可按土壤深度绘制成曲线。当土壤被侵蚀时,质量吸收系数线就发生变化。最大μM值反映了高原子质量元素包括铁(Fe)和盐基等风化产物的聚积.对所有被测的单个土体,最大μM亚层的下界与粘化层下界相一致。最大μM值位于最大粘粒含量和离子交换量(CEC)层以下1或2亚层。当粘粒含量最大层的一部分由于耕作混入顶土时,最大粘粒含量层的深度的改变导致对侵蚀量估计偏低。与轻度侵蚀的单个土体(对照)比较,粘化层和最大μM亚层下界的变化是侵蚀单个土体土壤流失量的最好指标。由于它们在土壤剖面中分布深,因而这些参数比粘粒含量最大层稳定,不易被加速侵蚀移去。这种方法经具有粘化层的土壤试验,适用于具有粘化层的淋溶土、老成土和软土地区土壤侵蚀研究。 | Ken R.Olson A.H.Beavers 樊振国 | 1989 | 水土保持科技情报1989，，2： | 1 |
| 4 | 正确选择密封的方法显示文摘引进技术的消化吸收引起了普遍的重视.而获得先进技术的方法往往被人忽视.殊不知正确的方法是技术进步的阶梯.这里介绍了国外正确选择机械密封的方法和步骤,对我们很有借鉴. | P.Abrams R.Olson 孙玲玲 | 1989 | 齐鲁石油化工1989，17，5： | 0 |
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