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241.
以测绘实验室管理工作的实际需求为目的,运用VB语言和Access数据库技术,开发了人员管理、实验教学管理、仪器设备管理和综合查询为主要功能模块的实验室管理信息系统,旨在提高测绘实验室管理水平和服务效率。 相似文献
242.
针对气象计量检定机构在组织和参加实验室间比对活动中在编制比对方案、参考值来源、结果评价方法、粗大误差的剔除、比对报告编制等方面的内容进行分析,探讨气象计量实验室能力。通过开展气象计量实验室间的比对工作,确立气象计量检定机构在社会上的专业计量检定地位,确保各计量标准量值的准确、可靠、一致,也为考察各实验室计量检定人员技术水平和数据处理能力,发现问题、积累经验,更好地开展气象计量检定工作,可以识别与同行各机构之间存在的差异,发现自身存在的问题,为自身的持续改进和质量管理提供信息。 相似文献
243.
总结了上海市检测中心各种实验室内楼宇自控系统的应用,对普通舒适性新风机组、空调机组以及高精度空调机组等机组的监控原理做了详细比较分析。 相似文献
244.
Air-flow geometry in air sparging of fine-grained sands 总被引:1,自引:0,他引:1
Laboratory visualization experiments in fine- to very fine-grained sands (grain diameter <0.21 mm) reveal a previously unrecognized
air-flow geometry. This air-flow geometry is termed "chamber flow" and is characterized by: (1) a significant horizontal component,
(2) pervasive air-flow coverage within a region demarcated by a distinct, irregular boundary, and (3) the presence of predominantly
vertical inlet and outlet channels. The attributes of chamber flow differ significantly from channelized flow and pervasive/bubbly
flow, which occur at larger grain sizes and have been described in the literature by several researchers. Previous research,
which indicates a dramatic increase in contaminant removal time in sediments <0.2 mm, indirectly corroborates the phenomena
observed in this study. The extent of sediment column affected by chamber flow of sparge air ranges from 4–54% on an area
basis, and is approximately 28% on a volume basis. These values indicate that chamber air flow has the potential to affect
a much larger percentage of the sediment column than either channelized or pervasive/bubbly flow. Because of the irregularity
of air-flow chambers, in terms of both form and frequency, a detailed knowledge of stratigraphy is important to maximize air-sparging
efficiency at sites where chamber flow is likely to occur.
Electronic Publication 相似文献
245.
246.
Geological and laboratory evidence for early generation of large amounts of liquid hydrocarbons from suberinite and subereous components 总被引:1,自引:0,他引:1
Suberinite, and subereous components of amorphous nature, comprise largely unrecognized, proficient sources of liquid hydrocarbons. Due to difficulties in recognizing the presence of subereous components and suberinite in organic sediments, the contributions of these liptinitic components to the organic input of source rocks are easily underestimated. Severe chemical alterations of suberinite in the vitrinite reflectance range of Ro = 0.35–0.60% are demonstrated. Organic geochemical data, obtained from samples subjected to natural maturation, reveal that subereous components/suberinite undergoes early thermal degradation to generate large amounts of hydrocarbons below Ro = 0.60%. Data obtained from laboratory maturation of immature, suberinite-rich coals indicate that about 50% of the potential of suberinite for generating C12+ hydrocarbons has already been exhausted during natural maturation of the samples, prior to the onset of the traditionally defined “oil window”. The present data (a) contradict the assumption that suberinite is mainly sourced by selective preservation/enrichment of a stable, highly aliphatic biopolymer, i.e. “suberan” and (b) suggest that suberinite contains appreciable amounts of aliphatic and aromatic moieties which are released at low thermal stress. 相似文献
247.
248.
Hortonian runoff was measured in the laboratory from uniform slopes of lengths of 1·5, 3·0, and 6·0 m for steady, high‐intensity rainstorms with durations of 1·0 to 7·5 min. A clear reduction in runoff per unit slope length was found as slope lengths were increased. This effect becomes more pronounced with decreasing storm duration. The runoff data were used to validate a simple process‐based model that combines the Philip‐two‐term infiltration equation with the kinematic wave overland flow principle. The predicted and experimental results agreed well. Laboratory findings were extrapolated with the aid of the model to slopes and rainfall durations similar to those found under West African conditions. The calculated reduction of runoff per unit length is similar to reported observations. Thus, this process‐based model can largely explain the phenomenon of runoff reduction with increasing slope length. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
249.
250.
改性污泥作填埋场覆盖材料室内试验研究 总被引:3,自引:0,他引:3
对采用不同石灰配比改性自来水厂污泥进行一系列室内土工试验,考察其改性后土性变化规律,研究改性后作为垃圾填埋场覆盖材料的可行性,探讨了合适的改性方案。初步认为按照一定泥灰比改性后的自来水厂污泥可作为覆盖材料的废弃物,并且能有效减少热收缩性。 相似文献