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264.
介绍了国外有关腐蚀性空气环境的分级标准及其检测方法。环境中的腐蚀性气体可对电子元器件及自动控制设备产生腐蚀,影响其性能。根据腐蚀性的严重程度,美国仪器学会标准中将腐蚀性空气环境分为四级。环境腐蚀性置于腐蚀性环境中的铜试条进行检测。 相似文献
265.
Data validation, as prescribed in guidance documents provided by the United States Environmental Protection Agency (EPA),
yields legal evidence that an analytical laboratory has performed analyses according to predetermined specifications. This
validation process, because it involves only the checking of procedural documentation, provides minimal information concerning
the technical validity of the data. Unfortunately, in the minds of many, the performance of such a data validation has become
synonymous with technical validity. A better approach is to implement a routine program of referee analyses. That is, submit
a predetermined number of samples from the project to a second laboratory. A routine program of this type provides a self-checking
and self-correcting mechanism for determining whether data are technically valid.
Publication No. 3874, Environmental Sciences Division, ORNL.
Managed by Martin-Marietta Energy Systems, Inc. for the US Department of Energy under Contract No. DE-AC05-840R21400. 相似文献
266.
Frederick B. Lotspeich 《Journal of the American Water Resources Association》1980,16(4):581-586
ABSTRACT: A scheme is outlined to classify watersheds as ecosystems, based on their natural attributes. Two physical factors of the environment, climate and geology, are selected as state factors. Climate is the master factor that supplies energy and water to all ecosystems; geologic structure supplies the materal from which the forces of climate carve landforms to establish ecosystems. At the next lower level, soil and vegetation interact in a succession of transactions to produce a mosaic of tesseras within each watershed. It is these interacting tesseras that moderate climate and store energy within the ecosystem that influences the embedded stream. At the bottom of the scale is the stream with its passive role and inability to interact with the higher factors of the ecosystem. Thus, we have a controlling force consisting of two elements (climate and geology), a reacting force (soil and vegetation) that responds by circular conditioning to controlling forces, and at the lowest level, the stream which responds to all factors of the living system within its watershed. 相似文献
267.
John C. Clausen Kenneth N. Brooks 《Journal of the American Water Resources Association》1983,19(5):763-767
ABSTRACT The likelihood of expanded use of Minnesota's 3 million hectares of peatlands prompted the state to initiate a hydrologic study to characterize these groundwater-linked systems. Determining the quality of streamflow from these peatlands was an integral part of the study. Peatlands could be differentiated either on the basis of streamflow quality or on soil-vegetation characteristics. The quality of streamflow from 45 undisturbed peatlands was characterized by collecting samples five times in 1979-80 and analyzing them for 27 water quality characteristics. Runoff pH, specific conductance, alkalinity, calcium, and magnesium were used to classify the peatlands as bog, transition, or fen. Bog runoff was lower (α= 0.05) in pH, calcium, sodium, manganese, and ammonia nitrogen than fen runoff, but was higher in acidity, color, aluminum, humic and fulvic acid, and chemical oxygen demand than fen runoff. Bogs had more fibric peat of a lower pH than fens; fens exhibited tall woody shrubs which were virtually absent on bogs. 相似文献
268.
土地利用地学知识可应用于LIS智能化分析及辅助遥感影像解译,是国土信息化工程建设中值得深入研究的重要技术环节之一.明确了土地利用地学知识概念,构建了多数据源的土地利用地学知识体系,针对不同数据源分析了土地利用地学知识的获取及表达,并着重对土地利用地学知识辅助遥感影像解译进行了阐述,指出采用知识辅助高分辨率遥感影像解译是亟待深入开展研究的课题. 相似文献
269.
笔者从道路交通事故和景观方面 ,研究道路中央隔离设施的功能与特征。首先 ,利用对某城市道路中央有无隔离带情况下记录的交通事故数据 ,进行交通安全统计比较分析 ;其次 ,分别利用层次分析法和语言分级评价法 ,对城市道路中央双黄线、中央护栏隔离和中央绿化隔离 3种情况的景观进行分析 ;最后 ,通过综合分析给出分析结果 ,即中央绿化隔离、中央栅栏隔离带和双黄线隔离的评价顺序。 相似文献
270.
梁隆彪 《中国环境管理干部学院学报》2004,14(4):85-86,105
通过对医疗废物的危害和相关处理技术等问题的研究,提出枣庄市医疗废物处理对策的研究方案,为建立枣庄市医疗废物集中处理中心提供参考,可作为政府及相关业务主管部门的决策依据。 相似文献