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161.
Environmental Science and Pollution Research - In recent times, the persistent global environmental challenges have paved the way for the underpinning of climate change within the perspective of...  相似文献   
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163.
Polyurethane-based nanocomposites were prepared and their dielectric properties were characterized. Polyurethane (PU) composites were prepared with different organoclay content (1, 3, 5, and 10 wt% for all cases). The composites included quaternary ammonium salts such as 1-methyl-di-octyl-1 phenyl ammonium iodide (QAS-1), 1-methyl-di-nonyl-1 phenyl ammonium iodide (QAS-2), and 1-methyl-di-dodecyl-1 phenyl ammonium iodide (QAS-3) which were newly synthesized for modification of Na+-montmorillonite. Addition of aluminum silicate enhanced the dielectric properties at a constant concentration. Dielectric constants of nanocomposites compounded with 3 %- and 5 %-organoclay were close in value. The characterization of PU/organoclay composites was carried out using Fourier transform infrared and X-ray diffraction.  相似文献   
164.
Indoor dust samples were collected from 40 homes in Kocaeli, Turkey and were analyzed simultaneously for 14 polybrominated diphenyl ethers (PBDEs) and 16 poly aromatic hydrocarbons (PAHs) isomers. The total concentrations of PBDEs (Σ14PBDEs) ranged from 29.32 to 4790 ng g?1, with a median of 316.1 ng g?1, while the total indoor dust concentrations of 16 PAHs (Σ16PAHs) extending over three to four orders of magnitude ranged from 85.91 to 40,359 ng g?1 with a median value of 2489 ng g?1. Although deca-PBDE products (BDE-209) were the principal source of PBDEs contamination in the homes (median, 138.3 ng g?1), the correlation in the homes was indicative of similar sources for both the commercial penta and deca-PBDE formulas. The PAHs diagnostic ratios indicated that the main sources of PAHs measured in the indoor samples could be coal/biomass combustion, smoking, and cooking emissions. For children and adults, the contributions to ∑14PBDEs exposure were approximately 93 and 25 % for the ingestion of indoor dust, and 7 and 75 % for dermal contact. Exposure to ∑16PAHs through dermal contact was the dominant route for both children (90.6 %) and adults (99.7 %). For both groups, exposure by way of inhalation of indoor dust contaminated with PBDEs and PAHs was negligible. The hazard index (HI) values for BDE-47, BDE-99, BDE-153, and BDE-209 were lower than the safe limit of 1, and this result suggested that none of the population groups would be likely to experience potential health risk due to exposure to PBDEs from indoor dust in the study area. Considering only ingestion + dermal contact, the carcinogenic risk levels of both B2 PAHs and BDE-209 for adults were 6.2 × 10?5 in the US EPA safe limit range while those for children were 5.6 × 10?4 and slightly higher than the US EPA safe limit range (1 × 10?6 and 1 × 10?4). Certain precautions should be considered for children.  相似文献   
165.
Forest road design and construction are time-consuming and complicated because various risk factors can be encountered during the process. The aim of this study is to comprehensively assess the risk factors in forest road design and construction using the fuzzy analytic hierarchy process (AHP) method in Turkey, thus contributing to the proper performance of these activities. Within the scope of the study, six main risk factors and 22 sub-risk factors were identified based on literature review. In order to determine the weights of the relevant risk factors, the opinions of three different groups [(group 1: academicians), (group 2: forest engineers (private sector employees + public sector employees)), (group 3: group 1 + group 2)] about the risk factors were obtained. Relevant risk factor weights were determined using the fuzzy AHP method. According to group 3, the most important main risk factors are technical risks and environmental risks. In addition, the most important sub-risk factors for each relevant main risk factor were incorrect road alignment, inadequate work safety in the field, insufficient capital, legal problems on the road alignment, landslide risk during road construction, and illegal logging. Differences were observed between groups 1 and 2 in the weight rankings of relevant risk factor. The results demonstrate that the fuzzy AHP method can be used effectively to assess the risks of forest road design and construction.  相似文献   
166.
To evaluate the effects of cigarette smoking and biomass (dried dung) smoke on the oxidant–antioxidant status, three groups each with 5 rabbits were used. Groups of rabbits were exposed to either cigarette smoke, dried dung smoke or dry air, 1?h daily for one month. Protein carbonyls, prostaglandin F and malondialdehyde levels were significantly increased and protein sulfhydryls levels were significantly decreased in the cigarette smoke group compared with the control group. Only protein sulfhydryls levels were significantly decreased in dung group compared with the control group. Short course exposure to both cigarette smoke and biomass smoke decreased plasma antioxidant levels but only cigarette smoke increased plasma oxidant levels, whereas biomass smoke did not produce any change.  相似文献   
167.
The effects of exposure of tilapia (Oreochromis mossambicus) to sublethal concentrations of lead on hematological and immunological parameters were investigated. The fish were semistatically exposed to low (L) (0.5 mg L?1), medium (M) (2.5 mg L?1), and high (H) (5 mg L?1) lead concentrations for 14 days. At the end of the trial, red blood cell (RBC) count, hematocrit (Hct) ratio and hemoglobin levels showed significant decreases in M and H groups, while RBC was significantly increased in L group compared to control group. Lysozyme activity showed a decrease in all groups on day 14 compared to control. A decrease in myeloperoxidase activity was seen in M and H groups on day 7, and in all treatment groups on day 14. In conclusion, it was found that exposure of O. mossambicus to lead concentrations affected hematological and immunogical parameters adversely.  相似文献   
168.
In the last few decades, metal oxide nanoparticles have shown impact in various areas, and such an impact causes an increased release in a different environment like soil, water, or air. A limited number of studies on soils showed that the biochemical parameters were affected by the metal oxide nanoparticles. However, the influence of metal oxide nanoparticles on soil elements has not been investigated. For this aim, zinc oxide nanoparticles were applied to two different soils; also, the effect of planting on soil elements was investigated via the cultivation of various plants roots (taproots, fibrous, bulb). Soils were treated with zinc oxide nanoparticles at 0, 1.0 and 20.0?mg during 4 weeks. Then, surface soil samples were collected and digested using an acid digestion procedure. Some biochemically important elements (Ca, Zn, Mg, Fe, Al, Cu, Co, Ni) were determined using a microwave plasma atomic emission spectrometer. The effect of time and dose-dependent zinc oxide nanoparticles on the element contents of different soils was investigated during planting, and the results were statistically evaluated.  相似文献   
169.
The aim of this study is to propose the use of a functional data analysis approach as an alternative to the classical statistical methods most commonly used in oceanography and water quality management. In particular we consider the prediction of total suspended solids (TSS) based on remote sensing (RS) data. For this purpose several functional linear regression models and classical non-functional regression models are applied to 10 years of RS data obtained from medium resolution imaging spectrometer sensor to predict the TSS concentration in the coastal zone of the Guadalquivir estuary. The results of functional and classical approaches are compared in terms of their mean square prediction error values and the superiority of the functional models is established. A simulation study has been designed in order to support these findings and to determine the best prediction model for the TSS parameter in more general contexts.  相似文献   
170.
This study investigated the process of taking action to mitigate damage and prepare for an earthquake at the individual level. Its specific aim was to identify the factors that promote or inhibit individuals in this process. The study was conducted in Istanbul, Turkey—where an earthquake is expected soon—in May and June 2006 using qualitative methods. Within our conceptual framework, three different patterns emerged among the study subjects. Outcome expectancy, helplessness, a low socioeconomic level, a culture of negligence, a lack of trust, onset time/poor predictability, and normalisation bias inhibit individuals in this process, while location, direct personal experience, a higher education level, and social interaction promote them. Drawing on these findings, the paper details key points for better disaster communication, including whom to mobilise to reach target populations, such as individuals with direct earthquake experience and women.  相似文献   
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