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Heavy metals partitioning in the sediments of Izmir Inner Bay

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Journal of Environmental Sciences 2008年第4期20卷 413-418页

作者： guven Duyusen E AKINCI Gorkem Dokuz Eylul University Faculty of Engineering Department of Environmental EngineeringKaynaklar Campus35160BucalzmirTurkey.

Izmir Bay is known to be polluted by high concentrations of heavy metals and organic pollutants. Sediment samples taken from 7 different stations in Izmir Inner Bay were analyzed for their total organic matter content and, Cu, Cr, Pb and Zn. In addition, the chemical distribution of the metals were determined by means of the BCR （Community Bureau of Reference） Extraction Procedure （developed by European Commission for Standards, Measurement and Testing） which allows the determination of metals bound as four fractions; exchangeable and acid soluble, reducible （bound to iron-manganese oxides）, oxidizable （bound to organics） and residual. The results show that Izmir Inner Bay contains sediments with high metal concentrations. According to the chemical distribution of metals, Cr and Cu tend to accumulate mostly on the organic fraction of the sediment. Pb is mostly found in the reducible fraction where Zn is mobile in the sediment, and it is distributed evenly on each fraction.

关键词： heavy metal pollution Izmir Inner Bay sediment sequential extraction

Effect of sediment size on bioleaching of heavy metals from contaminated sediments of Izmir Inner Bay

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Journal of Environmental Sciences 2013年第9期25卷 1784-1794页

作者： Duyusen E.guven Gorkem Akinci Dokuz Eylul University Faculty of Engineering Department of Environmental EngineeringKaynaklar Campus35160 Buca Izmir Turkey

The effect of sediment size on metals bioleaching from bay sediments was investigated by using fine （〈 45 μm）, medium （45-300 μm）, and coarse （300-2000 μm） size fractions of a sediment sample contaminated with Cr, Cu, Pb, and Zn. Chemical speciation of the metals in bulk and size fractions of sediment were studied before and after bioleaching. Microbial activity was provided with mixed cultures of Acidithiobacillus thiooxidans and Acidithiobacillus ferrooxidans. The bioleaching process was carried out in flask experiments for 48 days, by using 5% （W/V） of solid concentration in suspension. Bioleaching was found to be efficient for the removal of selected heavy metals from every size fraction of sediments, where the experiments with the smaller particles resulted in the highest solubilization ratios. At the end of the experimental period, Cr, Cu, Pb and Zn were solubilized to the ratios of 68%, 88%, 72%, and 91% from the fine sediment, respectively. Higher removal efficiencies can be explained by the larger surface area provided by the smaller particles. The changes in the chemical forms of metals were determined and most of the metal releases were observed from the reducible and organic fractions independent from grain size. Higher concentrations were monitored in the residual fraction after bioleaching period, suggesting they are trapped in this fraction, and cannot be solubilized under natural conditions.

关键词： sediment sediment size heavy metals bioleaching Acidithiobacillus microbial activity

CVaR-based stochastic wind-thermal generation coordination for Turkish electricity market

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Journal of Modern Power Systems and Clean Energy 2019年第5期7卷 1307-1318页

作者： Aycan AYDOGDU Osman Bulent TOR Ali Nezih guven Department of Electrical and Electronics Engineering Middle East Technical UniversityAnkara 06800Turkey The Bucharest University of Economic Studies BucharestRomania

Uncertainties in wind power forecasting,dayahead and imbalance prices for the next day possess a great deal of risks for the profit of generation companies participating in a day-ahead electricity *** companies are exposed to imbalance penalties in the balancing market for unordered mismatches between associated day-ahead power schedule and real-time *** of wind and thermal power plants alleviates the risks raised from wind *** paper proposes a novel optimal coordination strategy by balancing wind power forecasting deviations with thermal units in the Turkish day-ahead electricity *** main focus of this study is to provide an optimal trade-off between the expected profit and the risk under wind uncertainty through conditional value at risk(CVa R)*** problem is formulated as a two-stage mixed-integer stochastic programming problem,where scenario-based wind power approach is used to handle the stochasticity of the wind *** programming approach is utilized to attain the commitment status of thermal *** of the coordination with different day-ahead bidding strategies and trade-off between expected profit and CVa R are examined with comparative scenario studies.

关键词： Conditional value at risk(CVaR) Windthermal coordination Electricity market Wind power Thermal power

TRIGONOMETRIC APPROXIMATION IN REFLEXIVE ORLICZ SPACES

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Analysis in Theory and Applications 2011年第2期27卷 125-137页

作者： Ali guven Balikesir University

The Lipschitz classes Lip（a,M） ,0 〈 a 〈 1 are defined for Orlicz space generated by the Young function M, and the degree of approximation by matrix transforms of f E Lip（or,M） is estimated by n-a.

关键词： Lipschitz class matrix transform modulus of continuity Nolund transform Orlicz space

Microstructure and mechanical properties of friction-stir welded St52 steel joints

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International Journal of Minerals,Metallurgy and Materials 2018年第12期25卷 1457-1464页

作者： Tevfik kucukomeroglu Semih M.Aktarer guven Ipekoglu Gurel Cam Department of Mechanical Engineering Karadeniz Technical UniversityTrabzon 61080Turkey Department of Automotive Technology Recep Tayyip Erdogan UniversityRize 53100Turkey Department of Mechanical Engineering Iskenderun Technical UniversityHatay 31200Turkey

The aim of this work is to investigate the mechanical properties and microstructures of friction-stir welded(FSWed) St52 structural steel joints. In this study, St52 steel plates with a thickness of 4 mm were butt-welded by friction-stir welding(FSW) using a tungsten carbide tool having a conical pin. The microstructure of the welded zone consists of equiaxed fine ferrite, grain boundary ferrite, Widmanstatten ferrite, and aggregates of ferrite + cementite. The microhardness measurements showed that the hardness of the welded zone was significantly higher than that of the base metal. The FSWed St52 joint exhibited a significant strength overmatching in the weld region and a strength performance similar to or slightly higher than that of the base plate.

关键词： friction-stir welding St52 steel microstructure mechanical properties

Approximation by Nrlund Means of Hexagonal Fourier Series

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Analysis in Theory and Applications 2017年第4期33卷 384-400页

作者： Ali guven Department of Mathematics Faculty of Arts and Sciences Balikesir University

Let f be an H-periodic HOlder continuous function of two real *** error ｜｜f-Nn （p;f）｜｜ is estimated in the uniform norm and in the Holder norm,where p=（pk）k=0∞is a nonincreasing sequence of positive numbers a... 详细信息

关键词： Hexagonal Fourier series Holder class Norlund mean.

Measurement and validation of tsunami Eigen values for the various water wave conditions

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Journal of Ocean Engineering and Science 2020年第1期5卷 41-54页

作者： Sudhir Kumar Chaturvedi Ugur guven Pankaj Kumar Srivastava Department of Aerospace Engineering University of Petroleum and Energy StudiesDehradun 248007India Department of International Affairs University of Petroleum and Energy StudiesDehradun 248007India Department of Petroleum Engineering&Earth Sciences University of Petroleum and Energy StudiesDehradun 248007India

This paper proposes the mathematical model to investigate how to compute and analyze the tsunami wave parameters and the retrieval of its early warning using remote sensing technique to improve the detection *** different methods available for the evaluation of the tsunami detection systems are also *** research work is to compute and analyze the tsunami wave parameters such as Eigen functions in deep,intermediate and shallow water *** computational and algorithmic analysis of tsunami wave parameters are achieved in three steps:the first step is to calculate the earthquake fault parameters such as length,width,area and displacement from the epicenter,which corresponds to the effect of its variation with respect to the earthquake *** variation of each fault parameters have been measured and recorded out over the certain moment of magnitudes(M).This shows smaller values as compared to the earthquake magnitude M 9.5 at which all the parameters shows very large *** second step involves the measurements of water wave angular frequency in deep,intermediate and shallower region of *** values of angular frequencies in deep water shows the lesser response as compared to other two water conditions because,in deep water the angular velocity of water particles travels with the lesser speed as compared to the shallower region as per Airy’s wave *** simulation results show the angular velocity in Deep Ocean is very less,moderate in the intermediate water and very high on the coastal *** indicates the higher impact on coastal *** third step involves the simulation study of measurement of tsunami Eigen functions such as orbital velocity,acceleration,wave potential in deep,intermediate and shallower water *** simulation result shows the resultant orbital velocity and accelerations in deep,intermediate and shallow water regions provides the similar response as angular velocity due to same proportion of the

关键词： Tsunami Eigen functions Monitoring Detection.

A brief review on tsunami early warning detection using BPR approach and post analysis by SAR satellite dataset

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Journal of Ocean Engineering and Science 2017年第2期2卷 83-89页

作者： Sudhir Kumar Chaturvedi Pankaj Kumar Srivastava Ugur guven Department of Aerospace Engineering University of Petroleum&Energy StudiesDehradun 248007India Department of Petroleum Engineering&Earth Sciences University of Petroleum&Energy StudiesDehradun 248007India

Tsunami early warning systems have provided to be the extreme importance after the tsunami that hit Japan in March *** research article presents a case study based on the tsunami detection using Bottom Pressure Rate(BPR)measurement and the post the analysis using the SAR datasets.A final decision based system using BPR has been studied to carry out the measurements of tsunami wave *** based study has also been carried out for the post tsunami *** filters are utilized to remove the speckle noise presents in *** scope of this work has also been proposed.

关键词： Remote sensing Tsunami damage detection Epicenter BPR

Bilateral papilledema in a child with osteogenesis imperfecta

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Eye and Vision 2016年第1期3卷 197-201页

作者： Selam Yekta Sendul Cemile Ucgul Atilgan Semra Tiryaki Dilek guven Department of Ophthalmology Sisli Hamidiye Etfal Training and Research HospitalEtfal Street34280 IstanbulSisliTurkey Department of Ophthalmology Ulucanlar Eye Training and Research HospitalUlucanlar street06030 AnkaraAltindagTurkey

Background:To present a female child patient with osteogenesis imperfecta who had bilateral *** presentation:A twelve-year-old girl with osteogenesis imperfecta was referred to our *** best corrected visual acuity of the patient was 5/10(corrected with+3.50 for right eye,+5.00 for left eye)with a standard Snellen scale at a distance of a 6 *** chamber,iris and lens examination of both of her eyes were *** her fundus examination,bilateral stage 2 papilledema and the wrinkles in papillomacular area were *** coherence tomography images revealed the macular pucker and thickening in the retinal nerve fibre layers of both *** tomography images revealed that there were ossifications in the optic chiasma and occlusion in all periorbital sinus ***:Osteogenesis imperfecta is a rare,autosomal dominant connective tissue disorder characterised by bone fractures,deafness and blue *** would like to draw attention to the clinical course of our patient with computed tomography,optical coherence tomography and visual field findings.

关键词： Optical coherence tomography Osteogenesis imperfecta Papilledema Visual field defect