Yazarlar
- Can, Zehra(2)
- Agar, Guleray(1)
- Aladag, Erdinc(1)
- Alpsoy, Lokman(1)
- Anar, Mustafa(1)
- Arman, Hasan(1)
- Asian, Ali(1)
- Baltas, Niniet(1)
- Ceker, Selcuk(1)
- Dabanli, Ismail(1)
- Demirel, I. Halil(1)
- Ecem-Bayram, Nesrin(1)
- Farizoglu, Burhanettin(1)
- Fil, Baybars Ali(1)
- Gercek, Ynsuf Can(1)
- Gul, Volkan(1)
- Karaali, Rabi(1)
- Kizil, Hamit Emre(1)
- Kocabey, Sefa(1)
- Kul, Sinan(1)
- Okan, Onur Tolga(1)
- Ozturk, Ilhan Tekin(1)
- Serancam, Ugur(1)
- Serencam, Ugur(1)
- Serencanr, Huseyin(1)
- Songur, Mehmet(1)
- Sozudogru, Onur(1)
- Yilmaz, Fatih(1)
- Yuksel, Ibrahim(1)
Yayınlar
- MakaleYalnız künye2020Scopus SJRQ4Innovative flow risk assessment with climate change perspective in Yesilirmak Basin
Serancam, Ugur; Dabanli, Ismail
Surface temperature increase due to global warming results in polar ice melting, snow cover thinning, changes in precipitation anomaly. All these phenological effects alert engineers, planners and administrators to be more sensitive against climate change-based risk effects on water structures. Vulnerability to natural disasters such as floods and droughts are expected to occur more frequent than past. Therefore, design and potential evaluation of water structures such as transmission channels, water wells, dams and hydraulic power generation facilities need to be re-evaluation. This re-evaluations procedure must be updated by taking into consideration climate change impacts with their risk assessments. For this purpose, the climate change-based risk levels are calculated from historically available records through possible trend tendencies, which are expressed in terms of trend slope. It has been observed that, in general, the climate change impacts are not significant on precipitation and runoff. This is due to the low trend slopes in the standardized hydro-meteorological time series. This point has been documented for Yesilirmak basin, where the climate change impact is very limited.
AtıfScopus1
İncele - MakaleYalnız künye2020Scopus SJRQ4Effect of fineness on lime stabilization of low plasticity clays
Yilmaz, Fatih; Kocabey, Sefa
In this study, stabilization with lime was investigated within the scope of surface soil stabilization. The main aim of the study is to examine the grindability of the lime and investigate the effect of grinded lime on the strength and durability behavior of stabilized soil. This paper is divided into two parts. The first part deals with the grindability of the lime. The second part analyses the results of geotechnical tests with grinded and ungrinded lime. Ungrinded lime, 90% of which is below 48 microns, was reduced to less than 20 microns. The test samples were prepared by adding 2%, 4%, 6%, 8% and 10% of grinded and ungrinded lime to a low plasticity clay according to the Unified Soil Classification System. Curing times for strength tests were determined as 1, 7, 14 and 28 days. The properties of the prepared mixtures were investigated by their geotechnical properties such as index, strength and durability. In the light of the data obtained from the experiments, it is concluded that the fineness of the lime has a direct positive effect on the strength and durability characteristics.
- MakaleYalnız künye2019Scopus SJRQ4Comparison of cationic dyes (basic orange 2, basic yellow 2 and basic violet 3) removal from aqueous solution using clay as an adsorbent
Farizoglu, Burhanettin; Fil, Baybars Ali; Sozudogru, Onur; Aladag, Erdinc; Kul, Sinan
The present work aims to investigate the removal of three cationic dyes (Basic Orange 2, Basic Yellow 2 and Basic Violet 3) from aqueous solutions by montmorillonite under various experimental conditions. Cationic dyes were selected Basic Orange 2 (BO2), Basic Yellow 2 (BY2) and Basic Violet 3 (BV3). The effects of pH, initial dye concentration, adsorbent dose, agitation speed and ionic strength, on the removal of dyes were studied. According to the experiments results, it was shown, that maximum removal was achieved in less than 45 min. The results indicate that the montmorillonite can be used as a low cost alternative according to other adsorbents in the removal of dyes from wastewater. The maximum adsorption efficiency levels attained were as follows: 95.849% BO2, 99.562% BY2 and 99.169% BV3 onto montmorillonite at pH: 5.0, 100 mg/L initial dye concentration, 0.75g/L clay dosage, 300 rpm agitation speed, 0 M NaCl ionic strength and 293 K, reaction time of 45 min.
AtıfScopus2İncele - MakaleYalnız künye2019Scopus SJRQ4Fatty acid composition of sunflower seeds from different locations in the north of Turkey
Gul, Volkan
Because of sunflower is well adapted to the conditions of all region types, it ranks the first in terms of vegetable oil production in our country. The content of fatty acids that determine the quality of sunflower oil is affected by factors such as genotype and environment, especially climate and soil struc-ture. This research examines the oil and fatty acid ratios of sunflower grains grown on a producer basis and presented to the market in 2015 in Samsun (Bafra, Vezirkopru and Havza), Amasya (Merzifon), Corum (Center) and Tokat (Turhal) in the Middle Black Sea Region selected according to the density of oil sunflower to determine the quality of oil. According to the results of the research, average fat ratio was found to be between 41.57% and 45.67%, palmitic and stearic acids, which are basic saturated fatty acids, between 5.65% and 6.44% and from 3.84% and 4.81% linoleic acid (omega 6), linolenic acid (omega 3) and oleic acids (omega 9), which are unsaturated fatty acids, were found between 50.33 and 63.42%, 0.24 and 0.29% and 25.32 and 37.50%, respectively. These results indicate that the sun-flower seeds cultivated in the Amasya-Merzifon re-gion are at the forefront due to their oil quality char- A cteristics.
- MakaleYalnız künye2019Scopus SJRQ4Appropriate maceration duration for the extraction of propolis
Ecem-Bayram, Nesrin; Gercek, Ynsuf Can
The importance of the use of natural products as nutritional supplements in order to increase the quality of life and prevent diseases has increased in recent years. Among these products, propolis produced by honey bees is collected from plants and has a very complex structure in terms of chemical content. Propolis and its extracts have been used by humans for centuries because of its various bioactive properties. Although different methods can be used in the extraction stage, the most commonly used technique is extraction by maceration. However, there is no standard time period for extraction of propolis by maceration. We aimed to determine the changes in the concentrations of flavonoid group compounds pinocembrin, chrysin, tectochrysin, pi-nostrobin chalcone, gengwanin, naringenin and galangin from propolis samples exposed to seven different periods (1, 2, 5 10, 15, 20, 30 days) of maceration using GC-MS. The flavonoids pinocembrin, chrysin, tectochrysin, and naringenin reached their maximum concentrations at the end of 15 days of maceration and a decrease in their concentrations was observed after this period. The concentrations of other flavonoids did not show a steady increase or decrease with different maceration times. As a result, it can be said that the appropriate duration of maceration to extract the flavonoids responsible for propolis' numerous activities varies depending on the origin of the propolis and the nature of the compounds to be extracted.
AtıfScopus9İncele - MakaleYalnız künye2019Scopus SJRQ4Some edible forest fruits their in vitro antioxidant activities, phenolic compounds and some enzyme inhibition effects
Okan, Onur Tolga; Serencanr, Huseyin; Baltas, Niniet; Can, Zehra
The purpose of the study was to analyze the po-tential health-pro mo ting components of some edible forest species of fruits. These are Service tree (Sor-bus domestica), Black rosehip (Rosa pimpinelli-folia), Red rosehip (Rosa carina), Bay fruit {Lawns nobilis), Cornelian cherry (Cornus mas), Autumn-olive (Elaeagrtus umbellate), and two different blue-berry fruits (Vaccinium arctostaplylos and Vaccin-ium myrtillus). In the present study, chemical and an-tioxidant activities, phenolic compounds as well as, inhibition effects on important enzymes (acetylcho-linesterase, xanthine oxidase and urease) of fruits were studied. Total polyphenol, flavonoid content, and the in-vitro antioxidant activity were evaluated by DPPH and FRAP. The sugar contents and phe-nolic compounds of the fruits were analyzed by HPLC-RJD and HPLC-UV. Fruits was determined the total polyphenol content (TPC) 1.10 to 19.87 mgGAE/g, total flavonoid content (TFC) 0.01 to 0.80 mgQE/g, DPPH values 0.22 to 6.03 mg/mL and FRAP values 4.24 to 168. 02 umol FeSO47H2O/g. All samples were determined various rate fructose and glucose. HPLC-UV revealed fruits contained different phenolic compounds. Inhibition values of the enzymes were expressed as inhibition concentra-tion (IC50: Mg/mL or ug/mL). It can be concluded that edible forest fruits are a potential source of anti-oxidants with therapeutic importance as well a natu-ral enzyme inhibitor.
AtıfScopus15İncele - MakaleYalnız künye2018Scopus SJRQ3Determination of in-vitro antioxidant, anti-urease, anti-hyaluronidase activities by phenolic rich bee products from different region of Turkey
Can, Zehra
In this study, enzyme inhibition of urease and hyaluronidase are clinically important functions were examined by different authenticity bee products. Different floral honey, pollen and propolis samples were analyzed in terms of total phenolic compounds (TPC), total flavonoid contents (TFC), ferric reducing antioxidant capacity (FRAP), cupric reducing antioxidant capacity (CUPRAC), and 2,2-diphenyl-1-picryhydrazyl (DPPH) free radical scavenging activities as antioxidant determinants. For the determination of the phenolic composition of the products, RP-UV-HPLC was used. TPC of the honey, pollen and propolis samples were ranged from 17 to 95 and 770 to 989 mg of gallic acid (GAE)/100g, 135-258 mg of GAE/g, and TFC was 1 to 10 mgQE/100g, and 78 to 99 mgQE/100 g, and 9 to 10 mg of QE/g, respectively. Among the bee products, propolis samples were showed the highest phenolic componds, that contained different quantity of protocatequic acid, catechin, caffeic acid, p-coumaric acid, p-hydroxybenzoic acid, ferulic acid and rutin. The urease inhibition vales (IC50) were changed from 7.02 to 33.25 mg/mL, 5.00 to 8.78 and 0.16 to 1.98 mg/mL in the honey, pollen and propolis samples, respectively. The hyaluronidase inhibition values (IC50) were changed from 0.02 to 0.46 g/mL, 0.02 to 0.26 g/mL and 3.26 to 9.21 μg/mL in the honey, pollen and propolis samples, respectively. Honey, pollen and propolis have a significant inhibition on the enzymes, the inhibition may be due to secondary metabolites of phenolic compounds and the mechanism of the inhibition should be studied in detailed.
AtıfScopus8İncele - MakaleYalnız künye2016Scopus SJRQ3Thermodynamic optimization of a zero CO2 emission cogeneration cycle
Karaali, Rabi; Ozturk, Ilhan Tekin
CO2 emissions that have the greatest negative impact on the greenhouse and the global warming that should be decreased or kept at the same rates. Today fossil fuels share 60 % of total electricity production of the world, which plays an important role on CO2 emissions. Thermal cogeneration and zero CO2 emission cycles have potential for reducing this effect. By taking into consideration the most applicable and important zero CO2 emission cycles, a new cycle is designed. Thermodynamic analyses and optimization of this cycle is studied with FORTRAN code. The optimization results of this cycle show that the maximum exergy efficiency of this new cycle is 64 %, which is 17.6 % higher than (0,544) the one for the air preheated cogeneration cycle (APHCC) and 18.7 % higher than (53,9) the absorption cooling zero CO2 emission cycle (ACZEC). In the introduced new cycle, steam and CO2 in the exhaust gases are condensed so that the condensing energy of them is regained. For that reason, the heat output and the electrical power of the introduced cycle is better than the other cogeneration cycles.
AtıfScopus3İncele - MakaleYalnız künye2016Scopus SJRQ3Renewable energy status and hydropower in some developing countries and focus on Turkey
Yuksel, Ibrahim; Arman, Hasan; Serencam, Ugur; Songur, Mehmet; Demirel, I. Halil
The share of renewable energies varies quite a lot in the developing countries, both in terms of total primary energy and electricity generation. Several different policy instruments are in use for promoting renewable energies, such as quota obligations, price subsidies, and taxes/tax exemptions on energy. Some countries such as Turkey, also have specific political programs for renewable energies. The obstacles and success conditions mainly deal with geographical, economic, administrative and political factors. The Republic of Turkey forms a natural bridge between Europe and Asia and the country has a relatively young population in both Europe and Asia. Turkey aims to utilize its energy potential, including from renewable sources, in a cost-effective manner. In its efforts to promote renewable energy, the government has focused on electricity, but has recently started to pay more attention to heat. On the other hand, Turkey's geographical location has several advantages for extensive use of most of the renewable energy sources. In this regard, renewable energy resources appear the most efficient and effective solutions for clean and sustainable energy development in Turkey. In addition to Turkey has a great hydropower, especially small hydropower potential. This paper deals with Turkey's renewable energy status in developing countries.
AtıfScopus1İncele - MakaleYalnız künye2015Scopus SJRQ3Determination of antigenotoxic effects of four lichen species by using human lymphocytes
Anar, Mustafa; Asian, Ali; Ceker, Selcuk; Kizil, Hamit Emre; Alpsoy, Lokman; Agar, Guleray
In this study, the geno-toxic and antigeno-toxic properties of the total extracts of four lichen species were investigated by using human lymphocytes. We obtained total extracts from R farinacea, X. parietina, U. articulataand U. filipendula lichen species. The results of our studies showed that 5 μM concentrations of AFB1 changed the frequencies of micronucleus (MN) and malondialdehyde (MDA) levels, as well as superoxide dismutase (SOD), glutathione (GSH) and glutathione peroxidase (GPx) activities. When 5,10 and 20 μg/ml concentrations of total extract were added to AFB1, the frequencies of MN and MDA levels were decreased, and SOD, GSH and GPx levels were increased. Consequently, our findings show that four lichen total extracts have strong antigenotoxic properties against aflatoxin Bi.
AtıfScopus3İncele