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71.
The dust samples from 52 different locations in central roads of Samsun City were collected in a study area of 40 km long for the purpose of determining total metal concentrations of dust samples by flame atomic absorption spectrometry. The concentrations of Cu, Pb, Co, Zn, Ni, Mn, and Cd were found in the ranges of 11.92–352.43, 5.47–223.57, 4.52–41.69, 40.85–173.10, 18.71–131.29, 133.19–179.13, and 0.02–6.16 mg/kg, respectively. The results showed that metal levels were higher around the industrial area than other locations. Principal component analysis was also carried out to ascertain the possible contributing factors towards the metal concentrations. Validation of the analytical results was tested by analysis of the BCR 032 Moroccan phosphate rock certified reference material.  相似文献   
72.
73.
Although arsenic (As) contamination of groundwater in the Bengal Basin has received wide attention over the past decade, comparative studies of hydrogeochemistry in geologically different sub-basins within the basin have been lacking. Groundwater samples were collected from sub-basins in the western margin (River Bhagirathi sub-basin, Nadia, India; 90 samples) and eastern margin (River Meghna sub-basin; Brahmanbaria, Bangladesh; 35 samples) of the Bengal Basin. Groundwater in the western site (Nadia) has mostly Ca-HCO(3) water while that in the eastern site (Brahmanbaria) is much more variable consisting of at least six different facies. The two sites show differences in major and minor solute trends indicating varying pathways of hydrogeochemical evolution However, both sites have similar reducing, postoxic environments (p(e): +5 to -2) with high concentrations of dissolved organic carbon, indicating dominantly metal-reducing processes and similarity in As mobilization mechanism. The trends of various redox-sensitive solutes (e.g. As, CH(4), Fe, Mn, NO(3)(-), NH(4)(+), SO(4)(2-)) indicate overlapping redox zones, leading to partial redox equilibrium conditions where As, once liberated from source minerals, would tend to remain in solution because of the complex interplay among the electron acceptors.  相似文献   
74.
Process equipment failures (PEFs) are one of the most important causes of process incidents occurrences. To investigate and prevent the PEFs, in addition to having the previous data, it is necessary to have some resources of the PEFs domain knowledge. Nowadays, PEFs data are usually retrieved from existent databases. Customary databases present only previously stored data of equipment failures but, for carrying out a comprehensive PEFs management it is necessary to have access to the PEFs desired knowledge and not only stored data. This paper aims to offer a knowledge base for the PEFs through adopting an ontological approach and then to use the proposed knowledge base for further applications particularly, process incident investigation activities. Through adding semantic search capability, the proposed knowledge base could upgrade the data presenting feature of the common databases into a knowledge presenting feature. Using this approach, the user would be able to extract the desired knowledge of the PEFs along the virtual stored data of occurred cases. The knowledge extraction process and the data mining of occurred incidents are both necessary for the PEFs investigation.  相似文献   
75.
The biological aerated filter (BAF) system, a new alternative in drinking water treatment, was designed to remove NH4+–N and Mn2+ simultaneously. This study aimed to control the aeration time in the BAF system for simultaneous NH4+–N and Mn2+ removal to achieve the Malaysian effluent quality regulation for drinking water. The experiment was conducted under four strategies of S1, S2, S3 and S4. The results demonstrated that acceptable levels of NH4+–N and Mn2+ were achieved over a 6 h aeration period (S1), producing effluent concentrations of 0.7 mg/L (93.2% removal) and 0.08 mg/L (79.6% removal), respectively. At the initial treatment of S1 and S2, the dissolved oxygen (DO) level rapidly increased until it reached a saturated concentration (6.8 mg/L DO) after 2 h period. Automatic on–off aeration time to maintain 3 mg/L DO set point (S4) resulted with a good effluent quality of NH4+–N and Mn2+ compared with the 2 mg/L DO set point (S3) which did not meet the regulated standard limits. Through the automatic on–off aeration time, the saturated and excessive DO levels in the BAF system can be avoided consequently reduce the wastage of energy and electrical consumption for simultaneous NH4+–N and Mn2+ removal from drinking water treatment.  相似文献   
76.
Journal of Material Cycles and Waste Management - The recycling potential of water treatment plant (WTP) sludge in asphalt concrete mixes as filler material was assessed in this study. Marshall...  相似文献   
77.
A pot-culture experiment was conducted in open-field conditions with highly cultivated locally transplanted (T) aman rice (Oryza sativa L.) named BR-22 in arsenic (As)-amended soil (0, 1.0, 5.0, 10.0, 20.0, 30.0, 40.0 and 50.0 mg kg−1 As) of Bangladesh to see the effect of As on the growth, yield and metal uptake of rice. Arsenic was applied to soil in the form of sodium arsenate (Na2HAsO4). Arsenic affected the plant height, tiller and panicle numbers, grain and straw yield of T-aman rice significantly (P ≤ 0.05). The grain As uptake of T-aman rice was found to increase with increase of As in soil and a high grain As uptake was observed in the treatments of 30–50 mg kg−1 As-containing soil. These levels exceed the food hygiene concentration limit of 1.0 mg kg−1 As. However, the straw As uptake varied significantly (P ≤ 0.05) from a low concentration of As in soil (5 mg kg−1) and the highest uptake was noticed in 20 mg kg−1 As treatment.  相似文献   
78.
Mitigation and Adaptation Strategies for Global Change - Turkey ranked seventh among cement-producing countries in the world, and the country is also one of the extensive producers in the world...  相似文献   
79.
Ataxia telangiectasia (AT) is a rare autosomal recessive disease characterized by progressive cerebellar ataxia, immunodeficiency, susceptibility to lymphoreticular malignancies and cancer predisposition, hypersensitivity to ionic radiation and chromosomal instability. In this study, we report a founder effect of AT with two different mutations: 1339 C > T and 6672 del GG together with 6677 del TACG, found in four Israeli Druze clans originating from three different Druze centers in the Middle East (Lebanon, Syria and Jordan). The 1339 C > T mutation, which results in a stop codon at position 447 of the ATM protein, was observed in two unrelated clans originating from Lebanon and Jordan. The 6672 del GG/6677 del TACG mutation was observed in two unrelated clans originating from Syria and Lebanon. In the present study, simple and fast detection assays were developed for both mutations. The ability to identify AT carriers routinely provides a unique opportunity for prenatal diagnosis, genetic counseling as well as marriage guidance in the Druze community. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   
80.
Over the last five decades, Malaysia has undergone rapid economic, social and environmental change, a process which is still continuing. The pursuit of socio‐economic progress has been accompanied by an unprecedented rate of change in the natural environment. In parallel to this development, governmental responses have also adapted over time to address emerging environmental situations. This article views the recent history of Malaysia's evolving policy response to development needs and environmental change as consisting of four distinct stages. Despite an impressive array of policy statements and strategies to implement sustainable development, many challenges remain today. A clear articulation of normative principles of sustainable development is of paramount importance, as is the monumental task of policy implementation. The article argues that the trajectory of Malaysia's policy on natural resources and environmental issues bears the characteristics of path‐dependent evolution.  相似文献   
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