Atatiirk University

Erzurum, Turkey

Atatiirk University

Erzurum, Turkey
SEARCH FILTERS
Time filter
Source Type

Korkmaz M.,Balikesir University | Ozmetin C.,Balikesir University | Fil B.A.,Atatiirk University | Ozmetin E.,Balikesir University | Yasar Y.,Balikesir University
Fresenius Environmental Bulletin | Year: 2013

The dyes and pigments have poisonous and mutagenic effect on humans and animals. In this study, the use of Bigadiç clinoptilolite (natural zeolite) as an adsorbent for removal of methyl violet dye from solutions was investigated. The dye adsorption experiments were carried out in batch mode as a function of pH (3-9), temperature (30-50 °C), ionic strength (0-0.1 M NaCl), clinoptilolite calcination temperature (0-200 °C), particle size (0-45; 180-425 urn) and solid-to-solution ratio (0.1-1.5g/50 mL). The dye adsorption capacity of the clinoptilolite mineral increased with high solution pH, high temperature, high salt concentration, low particle size and low solid-to-solution ratio. Clinoptilolite mineral provided higher adsorption capacity at calcination temperature of 50 °C. The equilibrium adsorption data fitted to the Langmuir isotherm rather than Freundlich model. The kinetic data could be explained by the pseudo second order model. Also, the kinetic data fitted to the intra particle diffusion model and this indicated that pore diffusion was rate controlling step in the applied batch process. Maximum adsorption capacity of the clinoptilolite mineral was calculated as 75.25 mg/g at pH 9. © by PSP.


Yazici K.,Karadeniz Technical University | Aptroot A.,ABL Herbarium G.v.d. | Aslan A.,Atatiirk University
Mycotaxon | Year: 2010

Three species of lichenized fungi - Arthonia calcarea, Buellia seauax, and Trapeliopsis gelatinosa - are reported here as new to Turkey. Buellia seauax and Trapeliopsis gelatinosa are also new to the Middle East. Distribution and substrate data are presented.


Demir M.,Eastern Anatolia Forestry Research Institute | Goktug T.H.,Adnan Menderes University | Bulut Y.,Atatiirk University
Fresenius Environmental Bulletin | Year: 2014

Water, as one of the crucial resources for the sustain-ability of vital activities of humans, is under a big pressure in the global context due to water scarcity, global warming and intense anthropogenic effects. In consequence of those changes on the environmental conditions, water resource management becomes crucial for the sustainabil-ity of human life. In this context, the paper focused on the Karasu River in Turkey, as one of the main tributaries of Euphrates crossing many provinces of Turkey, Syria, and Iraq. It has an international importance due to its geographical settings and is needed to be protected for the health and life of people living in those regions. Using this general information, the research on Karasu River has been designated to investigate and define anthropogenic factors effective on the pollution of the river in Erzurum Plain. This paper concluded with the proposal focused on alternative approaches for reducing levels of pollution. © by PSP.


Cankaya M.,Atatiirk University | Sisecioglu M.,Atatiirk University | Baris O.,Atatürk University | Gulluce M.,Atatürk University | Ozdemir H.,Atatiirk University
Applied Biochemistry and Microbiology | Year: 2010

Bovine lactoperoxidase (LPO) was purified from skimmed milk using amberlite CG-50-H+ resin, CM sephadex C-50 ion-exchange chromatography, and sephadex G-100 gel filtration chromatography. Lactoperoxidase was purified 20.45-fold with a yield of 28.8%. Purity of enzyme checked by sodium dodecyl sulphate-polyacrylamide gel electrophoresis method and a single band was observed. Km was 0.25 mM at 20°C, Vmax value was 7.95 μmol/ml min at 20°C (pH 6.0). Antibacterial study was done by disk diffusion method of Kirby-Bauer using Mueller-Hinton agar medium with slight modification. Bovine LPO showed high antibacterial activity in 100 mM thiocyanate-100 mM H2O2 medium for some bacteria (Brevibacillus centrosaurus, B. choshinensis, B. lyticum, Cedecea davisae, Chryseobacterium indoltheticum, Clavibacter michiganense pv. insidiosum, Kocuria erythromyxa, K. kristinae, K. rosea, K. varians, Paenibacillus validus, Pseudomonas syringae pv. populans, Ralstonia pickettii, Rhodococcus wratislaviensis, Serratia fonticola, Streptomyces violaceusniger, Vibrio cholerae-nonO1) respectively, and compared with well known antibacterial substances (levofloxacin, netilmicin). LPO system has inhibition effects on all type bacteria and concentration is really important such as LPO-100 mM thiocyanate-100 mM H2O2 system was proposed as an effective agent against many factors causing several diseases. © Pleiades Publishing, Inc., 2010.


Mindivan H.,Atatiirk University | Efe A.,Atatiirk University | Kayali E.S.,Technical University of Istanbul
Magnesium Technology | Year: 2014

Carbon nanotube (CNT) reinforced magnesium (Mg) matrix composite rod was successfully fabricated by mechanical ball milling followed by hot extrusion processes. CNTs used were multi-wall carbon nanotubes (MWCNTs). The starting Mg chips were ball-milled under argon atmosphere for 3 h to coat the surface of Mg chips with the pretreated MWCNTs. The CNT-coated Mg chips were then mixed with aluminum (Al) powder at the compositions of Mg-6 wt.% Al-x wt.% CNT (x = 0.5, 1, 2 and 4). The mixture was cold compacted and finally hot extruded. The distribution of CNTs was analyzed using a Scanning Electron Microscopy (SEM). Furthermore, the effect of CNTs and their amounts on the mechanical properties and corrosion behavior of the Mg composite were studied. Microstructural analysis revealed that the CNTs were well dispersed at the chip surfaces and were aligned with direction of the extrusion in the composites. As CNT content increased, chip size, density and electrical conductivity of the Mg composites decreased, a relatively constant value was obtained in the microhardness but a reduction was determined in compressive strength. While an increase up to 2 wt.% in CNT content reduced the corrosion rate of the composites, the corrosion rate increased at higher addition rates.


Paloluoglu C.,Atatiirk University | Bayraktar H.,Atatiirk University | Turalioglu F.S.,Atatiirk University | Bayraktar M.,Narman County Hospital
Fresenius Environmental Bulletin | Year: 2015

Atmospheric dry deposition of polycyclic aromatic hydrocarbons (PAHs) from traffic sources was investigated for the first time using a surrogate snow surface sampler at different distances (10 m, 100 m, and 400 m) from a highway with a heavy traffic load near the city center of Erzurum. The snow sampling was carried out twice. In the first sampling, fresh snow was taken immediately after heavy snow and placed in aluminum trays. The snow layer in the trays was used to obtain a dry surrogate surface. The second sampling was based on the extraction and analysis of 8-day-old snow subjected to dry deposition in aluminum trays. There were no significant differences in the concentrations of PAH compounds in the fresh snow samples, whereas there were significant differences in those measured in the aged snow samples at the end of the 8-day dry deposition period. The PAH concentration in the aged snow samples was 2-fold higher than that in the fresh snow samples. Most PAH compounds in fine particulate matter (PM) were detected 100 m and 400 m from the highway. In contrast, most PAH compounds in coarse PM were detected 10 m and 100 m away, possibly due to drifting from the 10 m point. Based on the source of the pollutants and the concentrations of PAHs, the PAHs sampled 10 m and 100 m from the highway were petrogenic, whereas those sampled 400 m away were pyrogenic.


Sonmez A.Y.,Kastamonu University | Hisar O.,Canakkale Onsekiz Mart University | Yanik T.,Atatiirk University
Fresenius Environmental Bulletin | Year: 2013

Heavy metals are among the most persistent of pollutants in aquatic systems due to their resistance to decomposition in nature. Four assessment methods (two pollution indexes and two fuzzy mathematical models - single-factor deciding and weighted average models) were used to check the level and characteristics of heavy metal pollution in the Karasů stream water. Several heavy metals such as Copper (Cu), Zinc (Zn), Manganese (Mn), Lead (Pb), Nickel (Ni), Cadmium (Cd) and Iron (Fe) were tested with these methods. A data set (12 months, total 180 measurements) was collected from 5 sampling points (A-E) of the River. The used criteria were classes, I-IV represents from clear to polluted one. Water quality was assessed as class IV from all water samples collected from the each station with single-factor index method. It was identified to be class IV from the samples of A, B, C and D stations, and class III from the sample of E station with the comprehensive index model. By using the fuzzy mathematical methods, the water quality were determined as classes of IV, IV, IV, II and II from the water samples of A, B, C, D and E stations respectively. Introduction of membership degree and weight of each factor to fuzzy mathematical models made the methods more reasonable in the field of water quality assessment. Therefore, these fuzzy mathematical methods might be quite convenient in evaluation of water pollution and classification considering the results of the present study. © by PSP.


Alibaba U.,Ministry of National Education | Sahin Y.,Atatiirk University | Turkez H.,Atatiirk University
Fresenius Environmental Bulletin | Year: 2011

A comparative study on elemental composition of various hazelnut (Corylus avellana L.) samples was conducted by using a sensitive method, wavelength dispersive X-ray fluorescence (WDXRF). Twenty-eight elements, such as Al, As, Bi, Ca, Cd, Cu, Fe, Mn, Ni, P, S, Sr, Zn, CI, Pb, K, Mg, Na, Ba, Rb, Si, Br, Cr, F, La, Se, Ti and Zr, were determined in hazelnut samples (n=10) grown under organic and conventional farming regimes. The obtained results from each group were analyzed statistically by using SPSS statistic program. It was observed that the concentration and peak intensity values of Ca, Fe, Mn, P, Mg, Zn, CI, Na, Br, Rb, F, K and Se elements were higher in hazelnut samples grown under organic farming regime but Al, Cr and Ni levels were found to be higher in samples grown under conventional farming regime. As, Bi, Cd, Pb, Ti and Zr contents were below the detection limits. Our findings clearly revealed that organic hazelnuts are likely to have higher nutritional mineral content. And the hazelnuts samples grown under conventional farming regime could contain harmful metals like Al, Cr and Ni that might affect the various systems and/or organs of humans and animals. © by PSP.


PubMed | Atatiirk University
Type: Journal Article | Journal: The West Indian medical journal | Year: 2012

An inadequate and imbalanced intake of protein and energy results in protein-energy malnutrition (PEM). It is known that bone mineral density and serum magnesium levels are low in malnourished children. However, the roles of serum magnesium and endothelin-1 (ET-1) levels in the pathophysiology of bone mineralization are obscure. Thus, the relationships between serum magnesium and ET-1 levels and the changes in bone mineral density were investigated in this study. There was a total of 32 subjects, 25 of them had PEM and seven were controls. While mean serum ET-1 levels of the children with kwashiorkor and marasmus showed no statistically significant difference, mean serum ET-1 levels of both groups were significantly higher than that of the control group. Serum magnesium levels were lower than normal value in 9 (36%) of 25 malnourished children. Malnourished children included in this study were divided into two subgroups according to their serum magnesium levels. While mean serum ET-1 levels in the group with low magnesium levels were significantly higher than that of the group with normal magnesium levels (p < 0.05), mean bone mineral density and bone mineral content levels were significantly lower (p < 0.05). In conclusion, many factors play a role in the pathophysiology of changes in bone mineral density in malnutrition. Our study suggested that lower magnesium levels and higher ET-1 levels might be important factors in changes of bone mineral density in malnutrition. We recommend that the malnourished patients, especially with hypomagnesaemia, should be treated with magnesium early.

Loading Atatiirk University collaborators
Loading Atatiirk University collaborators