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Dan M. Wells Ellis W. Huddleston Robert G. Rekers 《Journal of the American Water Resources Association》1971,7(1):124-132
ABSTRACT. .Eighteen rural lakes in Lubbock County were sampled on a routine basis following runoff-producing rainfall for a period of approximately eighteen months to determine whether or not runoff from intensively farmed agricultural areas contained significant concentrations of nitrates, phosphates, herbicides, or insecticides. An additional fifteen lakes lying within a triangle bounded by the cities of Plainview, Canyon, and Hereford, Texas, were sampled one time during the summer of 1969 to provide additional data regarding the nature and extent of the potential problem in an area with a different soil type and a slightly different cropping pattern. Based on results of detailed analyses of approximately two hundred samples of water collected from the lakes and an equal number of sediment samples collected from the same lakes at the same time, it appears that the concentrations of all chemical pollutants in runoff from agricultural lands in the High Plains are well below the allowable concentrations for drinking water. 相似文献
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In this study the focus is on the continuous ergonomic-focused development of a medical instrument that is capable of performing blood group serological tests. Primarily, a medical device must be clinically effective and safe. At the same time it must also meet the needs of its users. This calls for consideration of numerous ergonomic aspects. The development process of the product line in question was supported by a longitudinal series of carefully designed focus groups. Altogether, the 23 focus groups conducted included 245 participants from 72 laboratories. The aim of the empirical research was to collect users’ experiences, ideas and needs as inputs for the following phase of the product development process. During the mentioned focus group analyses, around 100 development proposals were conceived. Besides presenting more of the mentioned development proposals, the focus group analysis was shown as a proper methodology to involve end-users in the development and implementation of new technology or devices. 相似文献
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