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101.
Biological samples are extracted with n-hexane/acetone (60:40) and 1 mL of the concentrated extract is eluted through a pasteur pipette column prepacked with alumina (0.3 g) and silicic acid (0.25 g) with 10 mL n-hexane (containing 4% acetone). The fat and other co-extractives are retained by the column and clear eluate is directly injected on a GLC column for determination on electron capture detector. A comparison of the Pasteur pipette cleanup with the modified method of Cole et al. (1967) on 41 samples of fish, One Step Method, (Ahmad and Marolt (1986] on 86 samples of fish and Maunder et al. (1964) on 10 type of wildlife (100 samples) was made. The Pasteur pipette method gives results which are significantly higher (p greater than 0.5) than the other methods except the One step method. The Pasteur pipette method has a detection limit of 0.01 microgram/g for DDT and its metabolites.  相似文献   
102.
Used lubricating oil recycling using hydrocarbon solvents   总被引:1,自引:0,他引:1  
A solvent extraction process using new hydrocarbon solvents was employed to treat used lubricant oil. The solvents used were liquefied petroleum gas (LPG) condensate and stabilized condensate. A demulsifier was used to enhance the treatment process. The extraction process using stabilized condensate demonstrated characteristics that make it competitive with existing used oil treatment technologies. The process is able to reduce the asphaltene content of the treated lubricating oil to 0.106% (w/w), the ash content to 0.108%, and the carbon residue to 0.315% with very low levels of contaminant metals. The overall yield of oil is 79%. The treated used oil can be recycled as base lubricating oil. The major disadvantage of this work is the high temperature of solvent recovery. Experimental work and results are presented in detail.  相似文献   
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The maintenance of natural and virgin ecosystems against an unnecessary influx of humans requires a modern and efficient model such as the carrying capacity model to optimize the management and development of ecotourism in these areas. The model is one of the key tools for conservation and sustainability of these areas. The present research attempts to formulate a framework for the ecotourism carrying capacity model for sustainable development of Karkheh protected area in Iran. The information was collected using a citation method as well as, interviews with experts, and visitors, and director of the region with 24 key indicators being regulated by field surveys and library studies. In this study, the network analysis process model, the Pressure-State-Response conceptual model, and Arc GIS10.5 software were used to determine the potential for the establishment of ecotourism performance in the scale of 1: 50,000. In this research, 70 questionnaires were completed by experts in the field of environment and ecotourism to determine the relative importance of effective pressures. According to the results, the highest values belonged to physical carrying capacity (13,425,681 persons per day), ecological carrying capacity (2,482,226 persons per day), and social and culture (985,706 people per day), respectively. Based on the regional carrying capacity, the physical, ecological, and social carrying capacity index was calculated as 3356, 621, and 246 (greater than one), respectively. According to the results, the region has a high carrying capacity, which can accept visitors.  相似文献   
105.
Environmental Science and Pollution Research - Treatment of textile wastewater using ultrafiltration membranes was carried out in this study. Since membrane fouling is a major operational problem...  相似文献   
106.
Environmental Science and Pollution Research - The aquaculture industry is an efficient edible protein producer and grows faster than any other food sector. Therefore, it requires enormous amounts...  相似文献   
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Environmental Chemistry Letters - Research has recently focused on combinational therapy using nanocarriers to overcome the obstacles associated with conventional therapy of lung cancer. The...  相似文献   
109.
Journal of Material Cycles and Waste Management - The relationship between local structure and visible-light-activated photocatalytic ability of glass–ceramics prepared from Municipal Solid...  相似文献   
110.
Environmental Science and Pollution Research - The interaction and the interplay of climate change with oil palm production in the Southeast Asia region are of serious concern. This particularly...  相似文献   
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