Comparison of the attenuation properties for two different areas in eastern Anatolia,Turkey     

Ufuk Aydin  Şakir Şahin 《Soil Dynamics and Earthquake Engineering》2011

In this study, the attenuation properties of the crust and the quality factor of S wave in eastern Anatolia (Turkey) were determined by local earthquakes for two different areas, Oltu and Erzurum. Seismic wave attenuation can be changed with high pressure or structural effects. Therefore, we argued that the estimation of attenuation coefficient in seismic active zones in Eastern Anatolia is a very useful tool to determine seismic activities. It uses regional waveform data set from two stations, OLT and ERZ, for 95 events that occurred in these regions between 2001 and 2005. The attenuation has been determined using the Chobra–Alexeev model based on the epicenter distance–amplitude relations. This model allows for investigation of the effects of variations in attenuation properties for different areas. We introduced a new magnitude formula for these areas using the amplitude normalization methods for reference values M_L=4, so as to correct effects of the magnitudes. We also determined velocity of seismic waves. The average attenuation coefficient (α), average quality factor (Q_s) and P and S waves velocities were obtained with normalized amplitude values for Erzurum (ERZ) and Oltu (OLT) as 0.0135 km⁻¹, 37, 6.20 km/s and 3.38 km/s and 0.0151, 34, 6.13 and 3.48.  相似文献   

Temporal and spatial biomonitoring of heavy metals in eastern Aegean coastal waters using Amphibalanus amphitrite   总被引：2，自引：0，他引：2  

Onen SA  Kucuksezgin F  Kocak F 《Marine pollution bulletin》2011,62(11):2548-2556

This biomonitoring study presents the spatial and temporal distributions of heavy metals in the soft tissues of a major fouling species Amphibalanus amphitrite living on hard substrate at different sites along the eastern Aegean coast. A. amphitrite has been chosen as a strong candidate for monitoring heavy metals. Sediment and seawater samples were also collected to detect their metal contents in order to gain more information on the environmental conditions and possible bioaccumulation patterns. The physico-chemical characteristics of sampling stations have been measured in order to characterize the sampling area. The order of metal concentrations in barnacles, sediment and seawater decreased in the following order Cu > Fe > Zn > Mn > Cd > Cr > Pb > Hg, Fe > Mn > Zn > Cu > Pb > Cr > Hg > Cd and Fe > Zn > Mn > Cu > Pb > Cr > Cd > Hg, respectively. These results showed that barnacles accumulate Cu in a higher degree than both sediment and seawater. Moreover, metal concentrations in barnacle have the potential for use in any future regulatory framework monitoring and eventually controlling ambient metal pollution levels.  相似文献   

The magnetic susceptibility of granitic rocks as a proxy for geochemical composition: Example from the Saruhan granitoids, NE Turkey   总被引：1，自引：0，他引：1  

Ali Aydin  Eric C. Ferr  Zafer Aslan 《Tectonophysics》2007,441(1-4):85-95

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Development of Predictive Models for the Specific Energy of Circular Diamond Sawblades in the Sawing of Granitic Rocks     

Gokhan Aydin  Izzet Karakurt  Kerim Aydiner 《Rock Mechanics and Rock Engineering》2013,46(4):767-783

This paper presents an experimental study on the sawing of granitic rocks by circular diamond sawblades. The influence of the operating variables and rock properties on the specific energy were initially investigated and analyzed. To determine the most significant operating variables and rock properties influencing the specific energy, statistical analyses were then employed and the models were built for the estimation of specific energy depending on the operating variables and the rock properties. Moreover, the derived models were validated through statistical tests such as the determination coefficient, t-test, F-test, and residuals. The results indicated that the specific energy decreased with the decreasing of peripheral speed and the increasing of traverse speed, cutting depth, and flow rate of cooling fluid, respectively. It was concluded that, rather than the physico-mechanical properties, the mineralogical properties were the dominant rock properties affecting the specific energy. Additionally, the peripheral speed was statistically determined as the most significant operating variable affecting the specific energy. The peripheral speed was followed by the cutting depth, traverse speed, and flow rate of cooling fluid with respect to their level of significance on the specific energy. Furthermore, the model results revealed that the developed models have high potentials as a guidance for practical applications.  相似文献   

Effects of Operational Parameters on Decolorization of C. I. Acid Red 88 by UV/H2O2 Process: Evaluation of Electrical Energy Consumption     

Nasser Modirshahla  Mohammad A. Behnajady  Rajab Rahbarfam  Aydin Hassani 《洁净——土壤、空气、水》2012,40(3):298-302

In the present study, effects of operational parameters on the electrical energy consumption for photooxidative process (UV/H₂O₂) for the decolorization of C. I. Acid Red 88 (AR88) have been investigated. In a series of experiments, 20 mg L^?1 of AR88 solution were irradiated in the presence of different concentrations of H₂O₂ (to find out optimum amount of H₂O₂) by UV light intensity of 30 W m^?2 for certain irradiation times. The decolorization of the dye followed pseudo first‐order kinetics, and hence, the figure‐of‐merit electrical energy per order (E_EO) is appropriate for estimating the electrical energy efficiency. The electrical energy consumption was determined during the variation of some parameters such as initial H₂O₂ concentration, initial dye concentration, UV light intensity, pH, and the gap size of solution. Results showed that electrical energy could be reduced by optimizing operational parameters.  相似文献   

Degradation of Malathion and Parathion by Ozonation,Photolytic Ozonation,and Heterogeneous Catalytic Ozonation Processes     

Fatma Beduk  Mehmet Emin Aydin  Senar Ozcan 《洁净——土壤、空气、水》2012,40(2):179-187

The oxidation of organophosphorus pesticides (OPPs), such as malathion and parathion, in aqueous solution was studied using conventional ozonation (O₃), photolytic ozonation (O₃/UV, O₃/UV/H₂O₂), and heterogeneous catalytic ozonation (O₃/TiO₂/UV) processes. Experiments were performed in batch mode at laboratory scale and processes were compared in terms of disappearance kinetics. The best results of pesticide mineralization were obtained when TiO₂ particles in combination with ozone (O₃) and UV photolysis (λ = 254 nm) were applied. Decomposition of 99% of parent compounds were achieved in 10 min and oxon derivatives were completely removed in 30 min. The initial reaction rate increases linearly with increasing catalyst amount. Toxicity measurements of the treated solutions were carried out in order to evaluate the efficiency of the treatment methods. No detoxification was achieved for O₃ and O₃/UV applications. Heterogeneous photocatalytic ozonation was shown to be feasible for achieving complete decomposition of OPPs and their oxon intermediates.  相似文献   

Geochemical traces of CO₂-rich fluid flow along normal faults in central Italy     

Fabrizio Agosta  reas Mulch †  Page Chamberlain  Atilla Aydin 《Geophysical Journal International》2008,174(2):758-770

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Interpretation of Magnetic Anomalies and Estimation of Depth of Magnetic Crust in Slovakia     

Kamil Rozimant  Aydin Büyüksaraç  Özcan Bektaş 《Pure and Applied Geophysics》2009,166(3):471-484

The magnetic map of Slovakia used in the paper was compiled as part of a project titled Atlas of Geophysical maps and profiles in 2001. The residual magnetic data were analyzed to produce Curie point estimates. To remove distortion of magnetic anomalies caused by the Earth’s magnetic field, reduction to pole transformation was applied to the magnetic anomalies using the magnetization angle of the induced magnetization. Anomalies reduced to the pole tend to be better correlated with tectonic structures. We applied a 3-km upward continuation to the residually compiled magnetic anomalies in order to remove effects of topography. The depth of magnetic dipoles was calculated by an azimuthally averaged power spectrum method for the entire area. Such estimates can be indicative of temperatures in the crust, since magnetic minerals lose their spontaneous magnetization according to Curie temperature of the dominant magnetic minerals in the rocks. The computed Curie point depths in the Slovakia region vary between 15.2 km and 20.9 km. Heat flow higher than 100 mWm⁻² occurs at the central volcanics and eastern part of Slovakia, where the Curie point depths values are shallow. The correlation between Curie point depths, heat flow and crust depth was investigated for two E-W cross sections. Heat flow and Curie point depth values are correlated with each other however, these values could not be correlated with crust depth. The Curie point isotherm, which separates magnetic and non-magnetic parts of the crust, is represented in two cross sections.  相似文献   

Use of microtremor in liquefaction hazard mapping   总被引：1，自引：0，他引：1  

M.A.A. Beroya  A. Aydin  R. Tiglao  M. Lasala 《Engineering Geology》2009,107(3-4):140-153

This study shows how microtremor measurements can be used as an aid to liquefaction hazard mapping and zonation, as demonstrated in Laoag City, Northern Philippines. From microtremor measurements, qualitative information on subsoil conditions was obtained and a site classification map was generated. The map was combined with the geomorphology-based liquefaction susceptibility map to produce an integrated liquefaction hazard zonation map. This integrated map is deemed to be more accurate in depicting relative liquefaction susceptibility since it combines information on the distribution of potentially liquefiable soils in terms of geology and grain characteristics with information on the stiffness and thickness of these soils. With information about the thickness of the deposits, an idea of the severity of liquefaction-related damage can also be gathered since thicker deposits relate to more serious damage. Plots of historical liquefaction cases, as well as borehole data and resistivity profiles in the study area, support the validity of the integrated map. The use of microtremor, therefore, constitutes an effective and inexpensive approach to liquefaction hazard zonation, and as such is very useful in less-developed countries like the Philippines and other areas where funds for more rigorous investigations are not always available.  相似文献   

A comparison of community and trophic structure in five marine ecosystems based on energy budgets and system metrics   总被引：1，自引：1，他引：0  

Sarah Gaichas  Georg Skaret  Jannike Falk-Petersen  Jason S. Link  William Overholtz  Bernard A. Megrey  Harald Gjster  William T. Stockhausen  Are Dommasnes  Kevin D. Friedland  Kerim Aydin 《Progress in Oceanography》2009,81(1-4):47

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