Yazar "Acar, Orhan" seçeneğine göre listele

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    Öğe
    Assessment of gross alpha and beta activity levels and element concentrations in spa waters from Siirt and AA±rnak, Turkey
    (Springer, 2017) Tegin, Brahim; Yolbas, Idris; Acar, Orhan
    Gross alpha and beta activity contents and element concentrations in well-known spa waters from the Siirt and the AA +/- rnak cities were determined and assessed by MPC-9604 multi-detector alpha/beta counting system and by wavelength dispersive X-ray fluorescence spectrometry. The 0.05-5.64 gross alpha and 0.06-2.76 Bq L-1 gross beta activity levels and element concentrations found in samples were compared with recommended values given by the World Health Organization, the US Environmental Protection Agency, Turkish Standards and literature results. Principal component and cluster analysis were also used to classify the spa waters due to element concentrations and three principal components calculated were about 91 % of the total variance in the data.
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    Öğe
    Determination of pesticide residues in varieties of pepper sold at different periods and provinces in Turkey and investigation of their adverse effects on human health and the environment
    (Taylor & Francis Ltd, 2024) Aktas, Serafettin; Aminzai, Mohammad Tahir; Tegin, Ibrahim; Yabalak, Erdal; Acar, Orhan
    Pesticides are dangerous chemicals that can harm to people and the environment when applied inappropriately or in excess. In this research, various pesticide residues were investigated in 48 pepper samples using liquid chromatography-tandem mass spectrometry (LC-MS/MS). All samples were collected randomly in two periods of time (September and December) from markets and greengrocers in four provinces (Siirt, Mardin, Diyarbakir, and Batman). Considering the means of the first and second periods, diclofop-methyl had the highest concentration of 29.4 & PLUSMN; 7.7 & mu;g kg-1, and diazinon had the lowest of 21.1 & PLUSMN; 4.6 & mu;g kg-1. Based on the maximum residue limits (MRLs) of pesticides specified in the Turkish Food Codex, pyrimethanil, bupirimate, and diclofop-methyl were found to be below the maximum acceptable residue limit, while pyridaphention, dinoseb, diazinon, and pirimiphos-methyl were found to be above the limit. Thus, the current study demonstrated the potential of LC-MS/MS as a crucial technique for accurate measurements and confirmations of pesticides in different pepper varieties.
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    Öğe
    Preconcentration and determination of Cu(II) and Cd(II) ions from wastewaters by using hazelnut shell biosorbent immobilized on Amberlite XAD-4 resin
    (2023) Teğin, İbrahim; Akdeniz, Selma; Alacabey, İhsan; Erol, Kadir; Acar, Orhan
    Hazelnut shell biosorbent immobilized on Amberlite XAD-4 polymer resin as solid phase extraction method was developed and used for preconcentration of Cu(II) and Cd(II) ions from aqueous solutions. Concentrations of analytes in solutions were determined by Flame Atomic Absorption Spectrometry after extraction with column technique. Functional groups of nutshell biosorbent immobilized on resin were characterized by Fourier transform infrared spectrometry. Optimized critical parameters for preconcentration of Cu2+ and Cd2+ ions from sample solutions with nutshell immobilized on the resin were the pH value of solution, type of eluent solutions, the flow rate of sample solution, quantities of nutshell biosorbent, Amberlite XAD-4 resin, and enrichment factors, respectively. Detection limits of Cu2+ and Cd2+ ions found were 0.29 ?g L-1 and 0.25 ?g L-1, respectively. The method proposed was applied for determinations of Cu2+ and Cd2+ ions in standard reference material (BCR-670 aquatic plant sample) for accuracy and applied to real water samples such as wastewater and Van lake water. At the 95% confidence level, relative standard deviations (RSDs) were found as 1.44% for Cd2+ and 1.21% for Cu2+ ions with three replicate measurements.
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    Öğe
    The chemometric study of multi-elemental composition in cultivated rhubarb from Iraq Kurdish Region and Turkiye Siirt
    (Taylor & Francis Ltd, 2023) Tegin, Ibrahim; Fattah, Bakhtiyar Mahmood; Canpolat, Gurbet; Acar, Orhan
    The concentrations of 30 elements (Li, Be, B, Na, Mg, P, K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Sr, Mo, Cd, Sn, Sb, Ba, La, Ce, Pt, Tl and Pb) in cultivated stems of rhubarb samples collected from the Kurdish region of Iraq (Sor, Rash, Karajar, Gara and Qalandar) and the Siirt region of Turkey (Pervari and Sirvan) were determined by Inductively Coupled Plasma - Mass (ICP-MS) spectrometry after acid digestion by a microwave digestor (Berghof Speedwawe MWS-3). The analysis revealed that the levels of Mg, K and P in the samples found were higher than other metals. Conversely, the presence of metals such as Pt, Tl, Be and Ar was found to be at significantly lower concentrations. The levels of the elements determined in the cultivated rhubarb samples were subjected to chemometric analysis using correlation analysis, principal component analysis (PCA) and cluster analysis (CA) techniques for the classification of metal content and the places of samples. Linear correlation coefficient values representing the element-to-element correlation data were analysed at the 95% and 99% confidence levels. The results of the study showed that the rhubarb samples could be classified into three groups based on their elemental compositions, using the PCA method. These findings were found to be consistent with the results obtained through cluster analysis (CA). This suggests that the chemometric techniques used in this study are effective for identifying patterns and relationships in complex datasets and could be useful for analysing other samples and identifying their origins. Overall, this study provides important insights into the elemental composition of Rhubarb samples and could have implications for food safety and quality control.