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    Adhesion and Corrosion Resistance Properties of Coatings Obtained From Modified Low-Molecular-Weight Polystyrenes
    (Taylor & Francis Ltd, 2006) Ahmetli, Gülnare; Kocak, A.; Sen, N.; Kurbanlı, R.
    In this study, as a continuation of our previous studies, chemical modification of low-molecular-weight polystyrenes (PSs) was carried out with various functional group modifiers: epichlorohydrin (ECH), maleic anhydride (MA) and acetic anhydride (AA), in a single stage using a cationic catalyst. It was determined that the amounts of the functional groups bound to the structure of the polymer depended on the molecular weight of the polymer used, and more functional groups were bound to the lower-molecular-weight PSs. It was found that the coating properties (adhesion properties and resistance to aggressive conditions) of the functional group containing PS to the metal surface depended on the structure and the amount of the functional groups bound to the aromatic ring of the polymer. In addition, it was observed that the PS modified with MA and ECH having carboxyl- and epoxy-groups in their aromatic rings had higher adhesion, as well as higher corrosion resistance properties. Various functional groups bound to the aromatic ring of the polystyrene and their amounts were determined by spectral and chemical analysis methods.
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    Alkylation of pyridinecarbaldehyde oximes with epoxy compounds
    (MAIK NAUKA/INTERPERIODICA/SPRINGER, 2007) Sen, N.; Kar, Y.; Kurbanov, S.
    O- and N-Alkylation products were obtained by reactions of pyridine-2-, -3-. and -4-carbaldehyde oximes with enantiomerically pure and racemic epoxy compounds (1,2-epoxypropane, 1-phenyl-1,2-epoxyethane, 1-chloro-2,3-epoxypropane, and 1-bromo-2,3-epoxypropane) in the presence of bases and under conditions of phase-transfer catalysis. A series of new amino alcohols was synthesized by condensation of amines with products of O-alkylation of pyridinecarbaldehyde oximes with 1-halo-2,3-epoxypropanes.
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    Obtaining of Boron as an Alternative Fuel from Borax with Various Methods
    (TAYLOR & FRANCIS INC, 2009) Sen, N.; Demir, C.; Demirbas, A.; Kar, Y.
    This study examined how to obtain elemental boron from borax. For this purpose, first boric acid (H3BO3) was obtained from borax decahydrate with using HCl and H2SO4. The boric was then converted to boron oxide using a dehydration process. It has been studied to reduce the boric acid and the boron oxide into elemental boron with using the elemental magnesium (Mg) and butyl nitrite (C5H9NO2), and also with using sawdust, charcoal, and cellulose. Then, the obtained elemental boron was subject to the burning process to prove its purity. The pure-elemental boron gave a strong green-colored flame when it was burned. Among these, the methods using the elemental magnesium (Mg) and butyl nitrite (C5H9NO2) in order to obtain elemental boron are more reasonable than those of the others.
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    The prevalence of the metabolic syndrome and its impact on the left ventricular systolic function in the patients with non-diabetic first ST elevation myocardial infarction
    (VERDUCI PUBLISHER, 2012) Yazici, H. U.; Poyraz, F.; Turfan, M.; Sen, N.; Tavil, Y.; Tulmac, M.; Vatankulu, M. A.
    Objective: Metabolic syndrome (MS) is common among the patients with myocardial infarction. The degree of the left ventricular systolic dysfunction is shown to be associated with poor prognosis after myocardial infarction. The aim of this study was to evaluate the prevalence of MS and its impact on the left ventricular systolic function in non-diabetic patients suffering first ST elevation myocardial infarction (STEMI). Material and Methods: This study was conducted prospectively in three centers. We included patients presenting with non-diabetic first acute STEMI. The systolic functions of the left ventricle were assessed through the ejection fraction, the wall motion score index (WMSI) and tissue Doppler myocardial S wave velocities. The diagnosis of MS was done based on the Adult Treatment Panel III clinical definition of the MS. Results: Among the 240 patients, 90 patients (37.5%) had MS but 150 patients (62.5%) were free of the MS. The patients in the MS group were older and the prevalence was higher among the females. Mean myocardial S wave velocities were significantly lower in the patients with the MS in comparison to the patients without the MS (6.70 +/- 1.68 vs. 7.39 +/- 1.64; p<0.01). LVEF and WMSI were similar in two groups. Conclusions: MS was highly common in nondiabetic patients with acute STEMI and left ventricular systolic function were more severely impaired in these patients. Our observations suggest that more severely impaired left ventricular systolic function after acute STEMI may contribute to the higher morbidity and mortality seen in the patients with MS after acute STEMI.
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    Removal of trichloroethylene (TCE) in up flow anaerobic sludge blanket reactors (UASB)
    (DIAGNOSIS PRESS LTD, 2007) Ozdemir, C.; Dursun, S.; Karatas, M.; Sen, N.; Sahinkaya, S.
    Low concentrations of chlorinated aliphatic compounds may be found in wastewater and contaminated soils from different industrial sources and in the air arising from these sources. Low levels of Volatile Organic Compounds (VOC) can be removed by adsorption, incineration and biofiltration methods. These methods have some disadvantages, such as low removal efficiency or high operation costs. Chlorine has been removed from the chlorinated aliphatic compounds by anaerobic conditions. The aim of this research was the investigation of biological treatment of VOC,v in high flow speed reactors. The resistance capacity of micro-organisms was investigated in an upflow anaerobic sludge blanket reactor (UASB) with automated control system, by feeding with co-substrate additions, by loading by different ratios of organic matter varying hydraulic retention time (HRT), maintaining stable concentrations of COD and Volatile Fatty Acids (VFA), pH,alkalinity, temperature (35 degrees C) etc. during the anaerobic treatment. Glucose, sodium sulphate, calcium chloride, ammonium bicarbonate, potassium phosphate and methanol were used as the co-substrates. In these studies the removal rates of TCE were opproximately 86.4-90. 0 %. The decomposition ratios were calculated for TCE as 0,231 mg g(-1)VSS d(-1). The highest methane ratio in the obtained biogas was 67.8 %,for TCE. Also, inhibition concentrations (IC) in 24 hours were determined as IC50,(.)31. 1 and IC25,(.) 9.9.