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The potential genotoxic activity in the surface waters of the Golden Horn Estuary was statistically evaluated utilizing a combination of appropriate parametric and non-parametric tests. The genotoxic activities that were associated with the water samples were determined by the SOS chromotest microplate assay. This assay utilizes β-galactosidase activity, alkaline phosphatase activity, and four different solvent controls, to generate reliable results when corrected induction factors (CIF) are used as quantitative measurements of genotoxic activity. The CIF values were obtained from a total of 384 different genotoxic experiments that were grouped into subsets according to the respective seasons and the selected sampling locations. A total of 160 subsets were statistically compared to assess any possible differences between the pairs of groups, with 95% confidence limits. The findings of this study clearly indicate that some seasonal variations exist in the CIF values at several sampling sites. However, no potentially hazardous impact to the aquatic environment was found in the estuarine system.  相似文献   
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Site classification of Turkish national strong-motion stations   总被引:1,自引:0,他引:1  
Since 1973, the General Directorate of Disaster Affairs of Turkey has deployed several strong-motion accelerographs at selected sites. Within the framework of the project entitled Compilation of National Strong Ground Motion Database in Accordance with International Standards, site conditions were investigated within the upper 30-m depth by surface seismic and standard penetration tests. Preliminary characterization of the sites is made by making use of both geophysical and geotechnical criteria of NEHRP Provisions and Eurocode-8 site classification systems. The liquefaction susceptibility of those sites which comprise saturated cohesionless deposits is also determined. Mean shear-wave velocity, mean penetration resistance, site class, and liquefaction susceptibility of each site are tabulated. The Turkish strong-motion database supplemented by detailed information on site conditions is a valuable source of information particularly for those studies that put emphasis on the relationship between site conditions and strong-motion parameters.  相似文献   
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Rapid improvements in telemetry technology and the general decrease in communication costs have raised a growing interest in low-cost wireless sensing units. This is especially the case for structural monitoring purposes, where they are becoming a more valuable alternative to conventional wired monitoring system. The main advantages associated with the use of wireless sensing unit include a considerable decrease in installation costs, decentralization of data analysis, and the possibility of broadening the functional capabilities by exploiting the use, at the same time and place, of different sensors. In this work, the design of a low-cost wireless sensing unit able both to collect, analyze, store, and communicate data and estimated parameters is presented. The suitability of a network of these low-cost wireless instruments for monitoring the vibration characteristics and dynamic properties of strategic civil infrastructures is validated during a ambient vibration recording field test on the Fatih Sultan Mehmet Bridge in Istanbul, Turkey.  相似文献   
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A selective and sensitive method for the preconcentration, separation, and determination of palladium with flame atomic absorption spectrometry using 4,15‐bis[(4‐methylphenyl)sulfonyl]‐20,21‐dinitro‐2,3,4,5,6,7,9,10,12,13,14,15,16,17‐tetradecahydro‐8,11‐ethano‐1,18,4,8,11,15‐benzodioxa tetraaza cycloicosine (TNACIN) on XAD‐2010 was developed. TNACIN–Pd(II) complex formed acidic aqueous solution (0.075–0.100 M HNO3) was accumulated on XAD‐2010 and then eluted with 1 M HCl in acetone. The effects of some analytical parameters including pH, TNACIN amount, sample volume, eluent type, and concentration, sample flow rate and matrix ions were studied for optimization of the method. Detection limit and precision were calculated for Pd(II). This method was also verified with CRM and internal standard, and satisfactory results were obtained.  相似文献   
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Rapid earthquake hazard and loss assessment for Euro-Mediterranean region   总被引:4,自引:0,他引:4  
The almost-real time estimation of ground shaking and losses after a major earthquake in the Euro-Mediterranean region was performed in the framework of the Joint Research Activity 3 (JRA-3) component of the EU FP6 Project entitled “Network of Research Infra-structures for European Seismology, NERIES”. This project consists of finding the most likely location of the earthquake source by estimating the fault rupture parameters on the basis of rapid inversion of data from on-line regional broadband stations. It also includes an estimation of the spatial distribution of selected site-specific ground motion parameters at engineering bedrock through region-specific ground motion prediction equations (GMPEs) or physical simulation of ground motion. By using the Earthquake Loss Estimation Routine (ELER) software, the multi-level methodology developed for real time estimation of losses is capable of incorporating regional variability and sources of uncertainty stemming from GMPEs, fault finiteness, site modifications, inventory of physical and social elements subjected to earthquake hazard and the associated vulnerability relationships.  相似文献   
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Abstract

Analyses of data from reservoir surveys and sediment rating curves are compared to predict sediment yield in three large reservoir watershed areas in Turkey. Sediment yield data were derived from reservoir sedimentation rates and suspended sediment measurements at gauging stations. The survey data were analysed to provide the volume estimates of sediment, the time-averaged sediment deposition rates, the long-term average annual loss rates in the reservoir storage capacity, and the long-term sediment yield of the corresponding watershed areas. Four regression methods, including linear and nonlinear cases, were applied to rating curves obtained from gauging stations. Application of the efficiency test to a power function form of a rating curve with nonlinear regression yielded the highest efficiency values. Based on the analysis of the sediment rating curves, sediment load fluxes were calculated by using average daily discharge data at each gauging station. Comparison of these two sediment yield values for each reservoir showed that the sediment yields from the suspended sediment measurements, SYGS, are 0.99 to 3.54 times less than those obtained from the reservoir surveys, SYRS. The results from the reservoir surveys indicate that all three reservoirs investigated have lost significant storage capacity due to high sedimentation rates.  相似文献   
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