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441.
Joseph Domagalski 《Journal of the American Water Resources Association》1996,32(5):953-964
ABSTRACT: Pesticides in stormwater runoff, within the Sacramento River Basin, California, were assessed during a storm that occurred in January 1994. Two organophosphate insecticides (diazinon and methidathion), two carbamate pesticides (molinate and carbofuran), and one triazine herbicide (simazine) were detected. Organophosphate pesticide concentrations increased with the rising stage of the hydrographs; peak concentrations were measured near peak discharge. Diazinon oxon, a toxic degradation product of diazinon, made up approximately 1 to 3 percent of the diazinon load. The Feather River was the principal source of organophosphate pesticides to the Sacramento River during this storm. The concentrations of molinate and carbofuran, pesticides applied to rice fields during May and June, were relatively constant during and after the storm. Their presence in surface water was attributed to the flooding and subsequent drainage, as a management practice to degrade rice stubble prior to the next planting. A photo-degradation product of molinate, 4-keto molinate, was in all samples where molinate was detected and made up approximately 50 percent of the total molinate load. Simazine, a herbicide used in orchards and to control weeds along the roadways, was detected in the storm runoff, but it was not possible to differentiate the two sources of that pesticide to the Sacramento River. 相似文献
442.
Characteristics of large cooking oil pool fires and their extinguishment by water mist 总被引:1,自引:0,他引:1
Z. Liu D. Carpenter A.K. Kim 《Journal of Loss Prevention in the Process Industries》2006,19(6):516-526
Large cooking oil pool fires, occurring in industrial oil cookers, present a severe hazard to food processing plants due to their size and the large amount of hot oil involved. This paper reports a series of full-scale fire experiments conducted in a large industrial oil cooker mock-up. The characteristics of large cooking oil pool fires and the effect of oil depth and hood position in the oil cooker on fire growth were studied. The use of water mist for extinguishing large oil pool fires and their extinguishing performance under different discharge pressure and with different types of water mist systems were investigated. Experimental results showed that the cooking oil underwent a substantial expansion in volume during heating. The fires developed quickly once the oil auto-ignited. The fire growth rate was affected by the oil depth in the pan and the hood position in the oil cooker. The water mist fire suppression systems effectively extinguished large cooking oil fires and prevented them from re-igniting. Their extinguishing performance was determined by the type of water mist system, discharge pressure and hood position in the oil cooker. 相似文献
443.
Nada Horvatinčić José Luis Briansó Bogomil Obelić Jadranka Barešić Ines Krajcar Bronić 《Water, Air, & Soil Pollution: Focus》2006,6(5-6):475-485
The process of eutrophication in form of intense plant growth has been observed in some lakes and water streams at the Plitvice
Lakes National Park in central Croatia. Here we investigate whether this phenomenon is a consequence of anthropogenic pollution
or due to naturally produced organic matter in the lakes. We applied chemical analysis of water at two springs and four lakes
(nutrients, dissolved organic carbon (DOC), trace elements) and measurements of surface lake sediments (mineral and organic
fraction analyses, trace elements) in four different lakes/five sites. The chemical composition of water does not indicate
recent anthropogenic pollution of water because the concentrations of most trace elements are below detection limits. The
concentrations of DOC and nutrients are slightly higher in the area of increased eutrophication-plant growth. Also the content
of organic matter in the sediment is at the highest level in areas with highest C/N ratio indicating that the organic fraction of this sediment is mainly of terrestrial origin. There is no significant difference
among the trace element concentration in the upper segment of all cores, deposited approximately during last 50 years when
higher anthropogenic influence is expected due to development and touristic activity, and the lower part of the cores, corresponding
to the period approximately 100–200 years before present. The content of trace elements and organic matter in sediments decreases
from the uppermost lake downstream. According to our results there is no indication of recent anthropogenic pollution in water
and sediment. Higher concentrations of DOC in water as well as phosphorus and some other elements in the lake sediment can
be a consequence of input of natural organic matter to the lake water. 相似文献
444.
445.
电力工业发展与环境保护 总被引:6,自引:3,他引:6
从我国电力工业发展历程、面临的主要环境问题、污染控制等方面全面简述我国电力工业环境保护取得的发展与成就;展望“十一五”电力发展目标及电力环保指标;分析了为实现环境目标需要实施的污染控制措施。 相似文献
446.
石油污染生物修复技术研究 总被引:2,自引:0,他引:2
本文概述了影响石油污染物生物降解修复处理的多种因素,对石油污染生物处理技术的发展进行了展望。其中主要影响因素包括:菌种的影响,菌种在不同的环境中和对不同碳链长度的碳氢化合物表现出不同的降解效率;石油物质本身物理化学特性的影响,如石油物质在水体或土壤中的浓度以及石油的粘度、沸点、折射率等特性;生存环境条件的影响,在接种入高效率的降解菌或利用土著微生物进行降解时,降解率受到生存环境中各种条件的影响,如表面活性剂、光照条件、吸附剂的利用、营养盐、共代谢底物、氧气、温度、盐度等。 相似文献
447.
448.
目前,我国对石油工业领域环境保护立法,采取的是特殊行业规制与一般规制相结合的模式。总体上看,我国石油工业环境保护领域已建立起初步的法制框架,但仍须进一步完善立法、执法、制订应急预案和建立信息公开机制等。 相似文献
449.
450.
含油污泥固化处理后油的迁移研究 总被引:3,自引:0,他引:3
利用紫外分光光度计和索氏抽提器,研究了温度、土壤含水率以及水泥与污泥的不同比例等因素在不同时间对含油污泥固化后油迁移的影响。试验结果表明:对于强度为3.84MPa的污泥固化块,油的迁移量从240h迁移6.8mg变为480h迁移178mg,之后变化较小。在20℃~30℃时,随着温度的增加,迁移量从6.8mg增加到20.6mg,超过30℃以后迁移量的增幅变小。水泥与污泥的比例从1∶0.8增加到1∶1.4,油的迁移量从256mg降到27.2mg,之后未检测到。960h后,迁移量达到348mg,此时土壤中油含量为1.16%,在环境的自净作用下,土壤能完全容纳;强度大于9.56MPa时未检测到油。这表明用固化法处理油田含油污泥是安全可靠的。 相似文献