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Determination of energy loss coefficient of rainwater and sewer manholes with CFD

Ozolcer I.H. | Dundar O.

Article | 2017 | Fresenius Environmental Bulletin26 ( 7 ) , pp.4716 - 4725

Overflowing and flooding in rainwater and sewer system manholes have become very common incidents in recent years. It is a well-known fact that floods spread out to large areas and cause loss of life and property. Consequently, using recent modelling approaches in the design of manholes has gained more importance than ever. The manhole geometry used today is given by national standards. Although the flood of a manhole is typically considered as a result of insufficient capacity of the system, the manhole geometry has distinctive role on the energy loss coefficients of manhole and water level in it. Nowadays, Computational Fluid Dyna . . .mic (CFD) programs and large computer capacity present opportunities in accurately modeling water flows in the manholes whose loss coefficients are calculated from the CFD modelling. In this study, water flow is modelled with CFD in a typical half bench manhole given by the Turkish Standards TS EN1917/AC. Moreover, three alternative manholes geometries are generated and water flow in these manholes are modelled with CFD. The energy loos coefficients of all manhole models are calculated and compared. © by PSP Daha fazlası Daha az

Sustainable hydroelectric energy methods: A proposal for the Western Black Sea region

Ozolcer I.H.

Article | 2017 | Fresenius Environmental Bulletin26 ( 8 ) , pp.5363 - 5371

In Turkey and the world, utilization of renewable energy sources is gaining importance in order to procure sustainable development along with the increase in energy demand and decrease in petroleum based energy sources. The most important renewable energy resources include hydroelectric, solar, wave and wind energies. Hydroelectric energy provides a safe and clean power supply to Turkey with positive effects on environment and climate, less cost in operation and maintenance, being long-lasting and domestic nature. Especially hydroelectric production of all renewable energy resources in Turkey is becoming increasingly significant in . . .total electricity production in that it has reached 16.1% in 2015 while it was only 3.8% in 1950. Small scale hydroelectric power plants are favored among clean energy resources since they are easily established, mostly sustainable and cheaper to operate. Pumped Hydropower Storage (PHS) systems have become common recently since they store energy in the form of water in an upper reservoir, pumped from another reservoir at a lower elevation. During periods of high electricity demand, power is generated by releasing the stored water through turbines in the same manner as a conventional hydropower station. On the other hand, during periods of low demand (usually nights or weekends when electricity is also lower cost), the upper reservoir is recharged by using lower-cost electricity from the grid to pump the water back to the upper reservoir. Furthermore, they can be operated every hour of the day when interconnected with renewable energy sources such as wind and solar to obtain maximum efficiency. In reality PHS's do not provide means to produce net gain in electricity but they are economically viable due to new pricing policies and can balance the load in the grid. In this study, general status of energy and hydropower of Turkey is investigated, and a proposal for a pumped hydropower storage in the Western Black Sea Region of Turkey is presented. © by PSP Daha fazlası Daha az

The effects of air pollution on carbonate stone monuments in urban areas (Sivas, Turkey)

Tecer L. | Cerit O.

Conference Object | 2002 | Fresenius Environmental Bulletin11 ( 8 ) , pp.505 - 509

In this study, the gypsum formation in carbonate stone by air pollutants has been investigated. The mineralogical composition (x-ray powder diffraction analysis) and texture (optical microscopy research of thin sections) of samples taken from the unsheltered surfaces of 13 historical buildings of different ages in various parts of Sivas have been examined. The gypsum formation on polluted surfaces has been caused and influenced by the polluted atmosphere of Sivas city, high relative humidity, the age of the buildings and stone characteristics.

Oil pollution at Turkish Black Sea coast and input of oil from Turkey to the Black Sea in 2004-2007

Güven K.C. | Coban B.

Article | 2012 | Fresenius Environmental Bulletin21 ( 12 ) , pp.3711 - 3717

In this work, we are reporting on the oil pollution in sea water and sediments of the Turkish coast, as well as the oil input calculated from Bosphorus undercurrent water into the Black Sea, between 2004-2007. The highest oil levels were found at the western part stations in the surface water at Terkos station (4), and in the sediments at Zonguldak station (13, 14). We suggest that the high pollution level is probably due to the pollution from Danube River, intensive ship traffic for the stations 1-6, the illegal discharge of ballast water from returning tankers, and also high tanker traffic for the stations 10-20 at the western par . . .t of the Turkish Black Sea. On the other hand, high pollution at the eastern coast is correlated with inputs from the neighboring petroleum loading stations. The calculated input of oil from undercurrent of Bosphorus was (in tons): 10422.0 (2004), 5153.10 (2005), 9385.10 (2006), and 6162.50 (2007), respectively. The oil input from the undercurrent of the Bosphorus to the Black Sea includes sewage of Istanbul and cities of the Sea of Marmara but also the pollution from Mediterranean/Aegean Sea. © by PSP Daha fazlası Daha az

Contents of trace elements and sulphur in the leaves of deciduous trees along the roads of Zonguldak, Turkey

Kaplan A. | Yorgancilar M. | Özdogan Y.

Article | 2009 | Fresenius Environmental Bulletin18 ( 7 B ) , pp.1243 - 1248

In this study, 16 trace elements (Al, B, Ba, Cd, Co, Cr, Cu, Fe, Li, Mg, Mn, Ni, Pb, Sr, V, Zn) and S were found in unwashed leaves of several deciduous tree species [Alnus glutinosa (L.) Gaertner, Platanus orientalis L., Salix babylonica L.]. Samples were collected from 28 points distributed over 5 sites representing different traffic intensities in the city of Zonguldak. The relationships of sampling sites were determined using the UPGMA method. According to the results of analyses, the trace element and S concentrations in the observed tree species were ordered as follows: S>Mg>Fe>Sr>Zn> B>Ba>Al>Mn>Cu>Pb> Ni> V>Cr>Li>Co>Cd in Aln . . .us glutinosa; S>Mg>Fe>Sr>Zn> Mn> Ba >Al>B>Cu>Pb> Cr>V>Li>Ni>Co>Cd in Platanus orientalis; S>Fe>Mg>Zn> Sr>Al>Ba>B>Mn>Cu> V>Pb>Ni>Li>Cr>Cd>Co in Salix babylonica. Significant positive correlations existed between the amount of heavy metals (r=0.81-1.00). The results are discussed in the context of prior studies. © by PSP Daha fazlası Daha az

Radioactivity measurement and dose assessment from surface soils around the Çatalagzi coal-fired power plant, Turkey

Aytekin H. | Baldik R.

Article | 2011 | Fresenius Environmental Bulletin20 ( 7 ) , pp.1642 - 1648

This paper presents a study on radioactivity measurements in surface soils around the Çatalagzi coal-fired power plant (ÇCFPP/ ÇATES) near the city of Zonguldak on the west of the Black Sea cost of Turkey. Soil samples were collected from 25 locations around the ÇCFPP and the activity concentrations of 226Ra, 232Th and 40K in the samples were determined using a gamma ray spectrometric system with an HPGe detector. The mean activity concentrations in soil samples were found as 47, 50 and 440 Bq kg -1 for 226Ra, 232Th and 40K respectively. In order to evaluate the radiological hazard of the natural radioactivity, the radium equivalent . . . activity (Ra eq), the absorbed dose rate (D) and the annual effect dose rate (AED) were calculated and compared with the internationally approved values. Our findings were also compared with the similar studies done in Turkey and other countries in the world. © by PSP Daha fazlası Daha az

HHCP contamination in marine alga laurencia pyramidalis bory de saint-vincent ex Kützing

Guven K.C. | Coban B. | Oz¨kirimli S. | Erdugan H. | Sezik E.

Article | 2013 | Fresenius Environmental Bulletin22 ( 3:00 AM ) , pp.925 - 927

This paper describes isolation and indentification of HHCP (Galaxolide®) as pollutant in red alga Laurencia pyramidalis Bory de Saint-Vincent ex Kützing (Syn. Laurencia obtusa var. pyramidata Bory ex J. Agardh) collected from Igneada (Black Sea coast) by GC/MS analysis. It was previously found as a pollutant in Danube River which consequently contaminates the Black Sea. It was suggested that this is a contamination of alga because it was not found in the same species collected from Assos (Çanakkale). This is the first record of HHCP contamination in algae. © by PSP.

Effects of pellet and extruded feed on fatty acid composition of European sea bass (Dicentrarchus labrax) using HRGC-MS

Aslan S.S. | Çoban B. | Tekinay A. | Gezgin T. | Guven K.C.

Article | 2009 | Fresenius Environmental Bulletin18 ( 1 ) , pp.112 - 116

Total lipid amount and fatty acid composition were determined and compared for cultivated European sea bass (Dicentrarchus labrax) from Turkey, which were fed with pellet and extruded commercial feed two or three times a day. Fatty acid analyses were carried out by gas chromatography-mass spectrometry. Among total fatty acids, palmitic (16:0), palmitoleic (16:1n-7), oleic (18:1n-9), linoleic (18:2n-6), eicosapentaenoic acid = EPA (20:5n-3) and docosahexaenoic acid = DHA (22:6«-3) were found to be the predominant fatty acids. The fish which received extruded feed (three times a day) had a slightly higher n-3/n-6 ratio of 1.41 compare . . .d to the other feeding types. It was found that the extruded feed given two times a day as fish diet resulted in the highest amounts of EPA, DHA, and total n-3 fatty acids Daha fazlası Daha az

Effects of seawater on geotechnical properties of a clay soil

Bilgen G. | Kavak A.

Article | 2010 | Fresenius Environmental Bulletin19 ( 8:00 AM ) , pp.1623 - 1628

The objective of this study is to investigate the possibility of using seawater on a clay type of soil instead of using tap or fresh water in road constructions fill works. When compared to the samples that were prepared using tap water, it was seen that the samples prepared with sea-water showed no change in consistency limit, but the soil's unconfined compressive strength value increased to 831 kPa from 300 kPa in 28 days time. The soil's soaked CBR values also increased by 7 times to a value of 27, while the swelling potential dropped to zero. These changes in soil properties may lead to transforming existing unsuitable in-situ m . . .aterials into suitable fill materials. With the improvement in the soil with seawater, the existing soil can easily be used as a suitable fill material in the lower layers of the filling in road construction works. These changes will reduce consumption of natural waters as well as the use of quarried stone and the transportation of filling material, thereby making several important contributions to the protection of natural resources. © by PSP Volume 19 - No 8a. 2010 Daha fazlası Daha az

Effect of carrier-solvent combination and stripping solutions on zinc transport by supported liquid membrane

Altın, Süreyya | Özgüven, Melih

Article | 2011 | Fresenius Environmental Bulletin20 ( 3 ) , pp.631 - 638

This study analyzed the zinc transport in supported liquid membrane (SLM) systems in which different anionic (Aliquat336) and cationic (D2EHPA) carriers, different solvents (kerosene and toluene) and different feed (deionized water and HCl) / stripping solutions (H3PO4, HCl and H 2SO4) were used. The results were modeled according to steady state (Fick's first law) and non-steady state kinetics approaches and the concordance of the models was discussed. It was observed from the experimental studies that 80.4% zinc transport could be achieved when deionized water was used as feed solution, kerosene/ D2EHPA (0.01 M) as membrane soluti . . .on combination and H3PO4(0.5 M) as stripping solution. Whilst the zinc transport efficiency was found to be 86.5% when HCl (1.0 M) was used as feed solution, toluene-Aliquat336 (0.02 M) as membrane solution combination and HCl (0.5 M) as stripping solution. Modeling studies established that the nonsteady state approach better represented zinc transport. It was therefore concluded that the zinc transport mechanism was affected by interface reactions rather than diffusion. © by PSP Daha fazlası Daha az

An investigation on the radiological influence of an underground coal mine in Zonguldak basin, Turkey

Aytekin H. | Baldik R.

Article | 2009 | Fresenius Environmental Bulletin18 ( 4 ) , pp.468 - 473

Üzülmez underground coal mine, one of 5 collieries in Zonguldak bituminous coal basin, is located on the West Black Sea region in Turkey. The radioactivity of the terres- trial natural radionuclides 226Ra, 232Th and 40K in rock and coal samples from 17 different locations in the mine were measured by using gamma spectrometry to determine the radiological implication of the mine. The highest radioac- tivity concentrations for 226Ra, 232Th and 40K were found to be 118.8, 49.1, 561.7 Bq kg-1 and 127.7, 145.3, 1125.9 Bq kg-1, in coal and rock samples, respectively. The ra- dium equivalent activity, the internal hazard index and the annu . . .al dose equivalent associated with the radionuclides were calculated to assess the radiological hazard of natural radioactivity in the samples, and compared with the inter- national recommended values. The measured activity con- centrations were also compared with those from other coun- tries in the world. The results show that radiological effects of natural radionuclides emanated from rock and coal are negligible for this mine Daha fazlası Daha az

An investigation on the radiological characters of spring waters in Zonguldak province (Turkey)

Aytekin H. | Bayraktaroglu N.

Article | 2016 | Fresenius Environmental Bulletin25 ( 12 ) , pp.6198 - 6201

In this study, to determine the radiological characters of spring waters used as drinking water in Zonguldak province a survey was carried out. Fortynine different water samples collected from the water reservoirs were analyzed. To determine the radioactivity level of the water samples the gross ? and ß activity concentrations were measured by using a gas flow proportional counter. The measured gross ß and ß activity concentrations were found to be from 2.9±0.8 to 170.5±41.7 mBq L-1 for alphas and from 15.4±11.2 to 244.3±53.0 mBq L-1 for betas. All the measured gross ? and ß activity concentrations are lower than the limit values re . . .commended by the World Health Organization (WHO). © 2016 PSP Daha fazlası Daha az

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