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111.
清洁生产在石油钻探行业中的应用 总被引:2,自引:0,他引:2
在介绍清洁生产理念的基础上,通过对石油钻探生产现状的分析,大量的引证了在钻探过程中应用清洁生产的可能性。对减轻钻井作业的末端处理负担,预防由于末端处理不完全造成的环境污染等方面作出了有益的探索。 相似文献
112.
This paper examines the effect of aviation safety education on passenger cabin safety awareness in knowledge, attitude, and behavior (KAB). The educational value of KAB has been addressed in various fields such as AIDS prevention and campus safety. KAB has been applied in aviation safety related areas, especially in training, such as crew resource management training, pilot training, and mechanic training. However, KAB has not been implemented in aviation passenger education in cabin safety. This paper uses the construct of “aviation safety education”, which is intended to influence airline passenger knowledge of, attitude toward, and behavior about cabin safety awareness. Passenger surveys were done at two Taiwan airports. The results show that aviation safety education positively affects airline passenger cabin safety knowledge, attitude, and behavior. We recommend safety education that involves accurate instruction about emergency equipment procedures, situational awareness, emergency responses, and relevant cabin-safety regulations.Our findings indicated that an increase in cabin safety knowledge positively affected airline passenger behavior, which supported knowledge–behavior consistency. We also found that a positive attitude toward cabin safety positively affected airline passenger behavior, which supported attitude–behavior consistency. The hypothesis that cabin safety knowledge positively affected passenger attitude – knowledge–attitude consistency was not supported. 相似文献
113.
The aim of the study was to compare the performances of the Brungraber Mark II (BM II) and Mark III (BM III) slipmeters. Friction measurements with the two slipmeters were conducted in a laboratory using four footwear materials, four floor types, and three surface conditions. Both the coefficient of friction (COF) values obtained with the slipmeters and the force platform-based COF values were measured. The COF measured with the BM II was slightly higher than that measured with the BM III with a R2 of 0.83. A comparison of the averaged normal force between the two slipmeters showed that the BM II generated a significantly higher normal force than the BM III at a low COF and the difference of the normal force between the two slipmeters decreased when the COF value was increased. The regression analysis results in this study showed that the force platform-based COF values were closer to the COF values obtained with the BM III than with the BM II. The R2 values for the regression model between the COF values obtained from the slipmeter and the force platform were 0.90 and 0.79 for the BM II and BM III, respectively. 相似文献
114.
115.
吨量煤体的自燃过程实验模拟研究 总被引:4,自引:0,他引:4
为更好地弄清矿井实际的煤自然发火规律,利用装煤量达5吨的大型实验台对两种烟煤分别进行了自燃模拟实验。大煤量的实验能够很好地模拟煤矿中煤低温氧化和传热传质共同作用导致的发火过程,实验得到的自然发火期与煤矿实际发火期也是一致的。实验中煤样从缓慢氧化变为快速氧化的临界温度为100~110℃。当煤温低于,临界温度时,煤样的升温受到空气流带走热量和向外界散热的影响很大,因此夹层水的保温作用就很关键。当煤温超过临界温度后,反应加快,温度急剧上升,散热的影响明显降低,反应主要受限于氧气的供应情况。 相似文献
116.
This article reports on soil samples collected from Hsiang-Shan wetland, Taiwan. Canonical discriminant analysis (CDA) was applied to identify an existing habitat type's scheme by identifying the physico-chemical properties of sediment in Hsiang-Shan wetland. The three constructed discriminant functions (CDFs) showed a marked contribution by most of the discriminant variables, and the recognition capacities in these three CDFs were 49.5, 32.8 and 17.7%. Our study revealed that the most important latent factors in Hsiang-Shan wetland are soil texture-caused factor, ocean current-caused factor, nutrient-caused factor, and the redox reaction-caused factor. And the most sensitivity parameters in this habitat followed the descending order: OBD, EC, Eh, sand, TN, porosity, STP, silt, VCP and pH. And the inhabited sediment properties for U. formosensis in terms of soil texture are sand, silt, and clay (34.05, 29.72, and 32.35%, respectively): that is clay loam soil. We also found that U. formosensis preferred to inhabit the upper intertidal zone, spending 8.41% of the time submerged. Vegetation coverage on the ground was less than 2.20%, showing that it preferred to live in a bare intertidal habitat. Concerning nest choosing, excavating burrows is more difficult when a high soil penetration force is required, and in this study the soil penetration force for 20 cm was found to be is 45.98 N/cm(2). The results will be helpful in developing a methodology for use by the government in refining its management programs. 相似文献
117.
The main objective of this study was to investigate occurrence of polycyclic aromatic hydrocarbons (PAHs) in the sources of the drinking water supply of Hong Kong. The main emphasis was on the Dongjiang River in mainland China which is the major source, supplying 80% of the total consumption in Hong Kong (the remaining 20% is obtained from rain water). Sediments were collected from four sites along the Dongjiang River and four reservoirs in Hong Kong during both the dry and wet weather seasons. The concentrations of total PAHs in the sediments ranged between 36 and 539 microg/kg dry wt. The lower levels were detected at the upstream site on the Dongjiang River and at the reservoirs in Hong Kong (44-85 microg/kg dry wt), while the mid- and downstream sites on the Dongjiang River were more polluted (588-658 microg/kg dry wt). Examination of the PAH profiles revealed that the mid- and downstream sections of the Dongjiang River contained high percentages of 4,5,6-ring PAHs, similar to the amounts of atmospheric particulate matter and road dust collected during the dry weather season from the Pearl River Delta region as reported in the literature. Seasonal changes were revealed in the reservoirs of Hong Kong, with higher PAH levels in the wet weather season than in the dry weather season. For those reservoirs in Hong Kong that store water from the Dongjiang River, a distinct seasonal pattern was also observed, namely, that under dry weather season conditions the PAHs found in the sediments were primarily from petrogenic source, while under wet weather season conditions they were from pyrolytic sources. No such pattern was detected in the reservoirs which stored only rain water. 相似文献
118.
The vulnerability analysis method has been widely used in many environmental fields. In recent years, the tool has succeeded in comprehensive assessment of environmental problems. This study applied the vulnerability and resilience analysis method on watershed conservation and grasped the environmental change capacity that watershed could bear. The Fei-tsui reservoir watershed in Northern Taiwan provided the setting for the case study reported herein. This study considered both internal and external effect factors, including watershed vulnerability, rainfall energy and the distances between the outlet and subbasins, and developed a new index, WP, for the priority restraints strategies on the land-use activities. The land-use restraint index can be a significant criterion for watershed protection and management strategies. 相似文献
119.
Because of fast urban sprawl, land use competition, and the gap in available funds and needed funds, municipal decision makers
and planners are looking for more cost-effective and sustainable ways to improve their sewer infrastructure systems. The dominant
approaches have turned to planning the sanitary sewer systems within a regional context, while the decentralized and on-site/cluster
wastewater systems have not overcome the application barriers. But regionalization policy confers uncertainties and risks
upon cities while planning for future events. Following the philosophy of smart growth, this paper presents several optimal
expansion schemes for a fast-growing city in the US/Mexico borderlands—the city of Pharr in Texas under uncertainty. The waste
stream generated in Pharr is divided into three distinct sewer sheds within the city limit, including south region, central
region, and north region. The options available include routing the wastewater to a neighboring municipality (i.e., McAllen)
for treatment and reuse, expanding the existing wastewater treatment plant (WWTP) in the south sewer shed, and constructing
a new WWTP in the north sewer shed. Traditional deterministic least-cost optimization applied in the first stage can provide
a cost-effective and technology-based decision without respect to associated uncertainties system wide. As the model is primarily
driven by the fees charged for wastewater transfer, sensitivity analysis was emphasized by the inclusion of varying flat-rate
fees for adjustable transfer schemes before contracting process that may support the assessment of fiscal benefits to all
parties involved. Yet uncertainties might arise from wastewater generation, wastewater reuse, and cost increase in constructing
and operating the new wastewater treatment plant simultaneously. When dealing with multiple sources of uncertainty, the grey
mixed integer programming (GIP) model, formulated in the second stage, can further allow all sources of uncertainties to propagate
throughout the optimization context, simultaneously leading to determine a wealth of optimal decisions within a reasonable
range. Both models ran for three 5-year periods beginning in 2005 and ending in 2020. The dynamic outputs of this analysis
reflect the systematic concerns about integrative uncertainties within this decision analysis, which enable decision makers
and stakeholders to make all-inclusive decisions for sanitary sewer system expansion in an economically growing region. 相似文献
120.
Brominated organic and inorganic by-products are generated during ozonation of groundwater containing high bromide concentrations. This study measured concentrations of bromate, bromoform, bromoacetic acids, bromoacetonitriles, bromoacetone, 2,4-dibromophenol and aldehyde generated by ozonation. The potential mutagenicity of ozonated waters was assessed using the Ames and Microtox tests. Test results for the 18 ozonated groundwater samples demonstrate that bromate formation is associated with high pH, bromide and alkalinity content, low levels of dissolved organic carbon (DOC) and ammonia, and low alkalinity. Brominated organic by-products were correlated with high bromide ion and natural organic matter content, and low ammonia concentrations. The Ames test results demonstrate that all extracts from ozonated water have mutagenic activity; however, the 18 raw groundwater samples had no mutagenicity. The Microtox test results also show that the ozonated water samples were highly toxic. Generally, both bromide and DOC content promoted the formation of ozonation by-products and mutagenicity. Controlling of bromide and DOC concentrations is an effective method of reducing potential by-product formation and eliminating mutagenicity problems associated with groundwater ozonation. 相似文献