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241.
骆正山  刘璐  张新生  王小完 《灾害学》2022,(1):68-71+76
为保障能源储备安全,探究雷电和静电对储气库安全的影响。根据雷电和静电理论,构建储气库雷静电概率模型,分析雷静电对储气库的影响。考虑天然气扩散的特殊性,选取高斯烟羽模型预测气体扩散范围,并结合闪火后果准则对闪火危害范围进行分析,构建CCPS-BST模型对爆炸危害范围预测,分析风速及大气稳定度对三种危害后果的影响。结果表明,雷静电会增加储气库泄漏后发生闪火和爆炸的概率,气体扩散范围和闪火后果沿主导风向呈梭形分布,蒸气云爆炸后果由中心向四周扩散,三种危害范围都与风速和大气稳定度呈相反的变化。研究结果可为多因素下储气库安全分析研究提供参考,为降低灾害后果和维护储气库的日常安全提供了理论依据。  相似文献   
242.
In this study, we investigated the effect of numerous regulations enforced since 1985 to improve air quality on ozone in Europe with the focus on Switzerland, using the Comprehensive Air Quality Model with Extensions (CAMx) for a specific summer period. Several emission scenarios for the year 2010 were also considered. The model results suggest that the emission reductions of ozone precursors should have been effective to reduce ozone production between 1985 and 2000 in northern Switzerland. However, observations do not indicate any significant change in surface ozone levels since early 1990s, except in the region of Zurich where there is a small negative trend. On the other hand, the model predictions match very well the spatial variability of the trends but the calculated trends are around 0.5 ppb year−1 lower than those observed. This difference is similar to the background ozone increase as suggested by the long-term observations at the high Alpine station Jungfraujoch. These results support the hypothesis that the decrease in local ozone production due to emission reductions might have been partly or completely compensated by the simultaneous increase in the background ozone. In 2010, a strict application of the Gothenburg Protocol in Europe would lead to a decrease in peak ozone concentrations by about 5% in Switzerland under the meteorological conditions applied. Our calculations also indicated that emission controls only in Switzerland would not be very effective to improve the air quality in the future. The further development of the background ozone will in any case be very important for the tropospheric ozone levels.  相似文献   
243.
The study was carried out in the Altindere Valley, which is an area appropriate for tourism activities with natural, historical and cultural values through all four seasons, with Yazlik Village in the centre and including the surrounding sites Cosandere village, Altindere village, hamlets (The Hamlets) and plateau areas. In this study, the goal is to set forth the ecological-based tourism potential in line with the concepts of intactness; conservation-use balance; and sustainability at natural, historical and cultural sites through a determined planning approach. In this respect, assessments have been made on the study area on the basis of the ‘Ecological Evaluation Method’, which has been developed for urban areas. Through the determination of quotients, classification and quantitative assessment of unweighted values were found for natural and cultural elements that show percentage (%) dispersion at the area (slope, exposition, soil, forest, vegetation, existing areas use, historical and cultural structure). ‘Weighted values’ were calculated by multiplying the determined factor weights and the unweighted inside grid values of the factors. With the results of grid values obtained, 10.58% Very Good, 48.82% Good, 19.7% Average, 8.82% Weak, and 12.05% Very Weak, ‘Ecological Based Tourism Potential Areas According to Natural, Historical and Cultural Factors’ have been identified.  相似文献   
244.
Local residents’ active participation is essential in protected areas to ensure achievement of conservation goals. One of the important steps for ensuring the active participation of local residents is to determine the perceptions and the factors that influence the perceptions of the local residents toward the protected area. In this context, the researchers of this study try to come up with the perception formed among the local residents toward the protected areas and especially toward Kure Mountains National Park (KMNP), the factors that would influence their perceptions and the ways how their perceptions are influenced. Multivariate linear regression was used to examine the putative influence of variables on perceptions toward protected areas. According to study results, the survey respondents have displayed a positive perception toward the protected areas in the world and in KMNP. It was determined that the respondents formed a positive perception from their economic, environmental and recreational interaction with KMNP. Also, the outcomes of this study showed that the perception developed by local residents toward the protected areas in the world and KMNP are influenced by gender, the level of satisfaction derived from the national park, duration of their residence in the national park, and that the perception that KMNP conservation are beneficial for the source values of the area, the current protection works in the world, as well as its impacts on their living conditions.  相似文献   
245.
137Cs in the marine environment mainly originates from fallout of atmospheric nuclear weapon tests, accidental releases from nuclear facilities, and from the Chernobyl accident. After the latter accident, many studies have been carried out in Turkey. The objective of this study is to assess the spatial distribution of 137Cs in the coastal marine environment of the Aegean Sea.

The concentrations of 137Cs in sediment, sea water, mussel (Mytilus galloprovincialis), and fish samples collected from the coast of the Aegean Sea at Izmir Bay and near Didim (Akbük) have been monitored for seasonal variability by the means of gamma spectroscopy: they vary between 0.10 ± 0.01 and 1.5 ± 0.3 Bq kg?1, 1.3 ± 0.1 and 4.3 ± 0.4 Bq m?3, <0.2 and 1.3 ± 0.3 Bq kg?1, and 0.20 ± 0.03 and 1.8 ± 0.3 Bq kg?1, respectively.  相似文献   
246.
Zinc borate is used as flame retardant for plastics and cellulose fibers, paper, rubber, and textiles. Despite its wide industrial use, there is limited information concerning its toxicity. The aim of the present study was to investigate the concentration dependence (0–280 mg L?1) of its genotoxic activity on cultured human lymphocytes by using sister chromatid exchange and chromosomal aberration assays. Total antioxidant capacity and the extent of oxidative stress were also determined. Zinc borate was found to be non-genotoxic at all tested concentrations. It exhibited antioxidant activity at concentrations lower than 40 mg L?1, and total oxidative stress levels were not changed at any applied concentration of zinc borate.  相似文献   
247.
In this diary study, we investigated multi‐level predictors of daily counterproductive work behavior (CWB) relying on the theoretical frameworks of affective events theory and the emotion‐centered model of CWB. We assessed significant work events, event‐based fairness perceptions, negative emotional reactions to work events, and employee CWB over a 10‐day period. We tested within‐person relations predicting CWB, and cross‐level moderating effects of two emotion regulation strategies (suppression and reappraisal). Results from a multi‐level path analysis revealed that significant work events had both direct and indirect effects on negative emotional reactions. Further, negative emotional reactions in turn mediated the relationships between significant work events and all forms of daily CWB as well as the relationship between event‐based fairness perceptions and daily CWB‐O. Results also supported the moderating role of reappraisal emotion regulation strategy on relations between significant work events and negative emotional reactions. Less support, however, was found for the moderating influence of suppression on the link between negative emotional reactions and CWB. Among the broad work event categories we identified, our supplemental analyses revealed that negative work events involving interactions with supervisors elicited the highest levels of employee negative emotional reactions. We discuss the theoretical and practical implications of these findings. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
248.
Coastal erosion may be caused by natural causes as well as human factors. Karasu town of the city of Sakarya in Turkey which is a touristic region on the Black Sea coast has been experienced a drastic coastal erosion. In recent years, this erosion reached the threatening dimensions for the structures in the settlement. According to the temporal analyses of Landsat satellite images, the maximum erosion on the coastline was detected 100 m between 1987–2013. The results of the study show that the harbour construct on the Karasu coast has the major impact on this event. The secondary factor is that the amount of the sediment carried by the Sakarya River was decreased in time due to different reasons. To prevent the coastal erosion, a series of offshore breakwaters were planned after the failed application of groins on the coastline. In this study, temporal changes of the coastline are investigated by the Landsat satellite data and land surveys, possible reasons of the erosion are discussed and the solutions are proposed regarding the coastal structures.  相似文献   
249.
Environmental Science and Pollution Research - Energy is an essential requirement for sustainable development, society, and the world. Turkey has been trying to increase the use of renewable...  相似文献   
250.

Introduction

This study presents the performance evaluation of a tailor-made passive sampler developed for the monitoring of tropospheric ozone.

Methods

The performance of the passive sampler was tested in the field conditions in terms of accuracy, precision, blank values, detection limit, effects of some parameters such as sampling site characteristics and sampling period on the field blanks, self-consistency, experimental and theoretical uptake rates, shelf life and comparison with commercial passive samplers.

Results

There was an agreement (R 2?=?0.84) between the responses of passive sampler and the continuous automatic analyser. The accuracy of the sampler, expressed as percent relative error, was obtained lower than 15%. Method precision in terms of coefficient of variance for three simultaneously applied passive samplers was 12%. Sampler detection limit was 2.42???g?m?3 for an exposure period of 1?week, and the sampler can be stored safely for a period of up to 8?weeks before exposure. Satisfactory self-consistency results showed that extended periods gave the same integrated response as a series of short-term samplers run side by side. The uptake rate of ozone was found to be 10.21?mL?min?1 in a very good agreement with the theoretical uptake rate (10.32?mL?min?1). The results of the comparison study conducted against a commercially available diffusion tube (Gradko diffusion tube) showed a good linear relationship (R 2?=?0.93) between two passive samplers.

Conclusions

The sampler seems suitable to be used in large-scale measurements of ozone where no data are available or the number of existing automated monitors is not sufficient.  相似文献   
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