Combined effects of soybean biodiesel fuel addition and EGR application on the combustion and exhaust emissions in a diesel engine

In this study, soybean biodiesel fuel was blended in 20 vol.% with diesel fuel and tested in a single-cylinder, DI, four-stroke diesel engine under four different engine loads (15, 11.25, 7.5 and 3.75 Nm) and 2200 rpm engine speed with different EGR rates (5, 10, 15%). The results showed that the maximum heat release rate and maximum in-cylinder pressure were mostly increased with the combined effects of biodiesel fuel addition and EGR application. Premixed combustion fractions were generally increased at all the engine loads with corresponding decrease in the diffusion combustion fractions. Combustion durations were generally stable while the center of the heat release rates shifted toward TDC. Reasonable increments on the BSFC and reductions on BTE as a maximum 6% and 3% occurred with 15% EGR, respectively. NOx and smoke emissions were improved simultaneously up to 55% and 15% at the high engine load, respectively. THC emissions at the low and medium engine loads decreased while deteriorations were observed with more than 5% EGR at the high engine load. Although CO emissions showed insignificant changes, there were increments at the high engine load. However, CO2 emissions were slightly higher for all the engine loads. © 2015 Elsevier Ltd. All rights reserved

İnönü Vakfı (1983)

Ankara : İhsan Doğramacı Bilkent Üniversitesi İktisadi, İdari ve Sosyal Bilimler Fakültesi, Tarih Bölümü, 2016.This work is a student project of the The Department of History, Faculty of Economics, Administrative and Social Sciences, İhsan Doğramacı Bilkent University.by Karabağ, Müzeyyen

Preparation and photoluminescence properties of aluminate phosphors produced by combustion synthesis

WOS:000454462500009PubMed:30248589In this work, Eu, Nd co-doped MAl2O4:Eu, Nd (M = Ca, Sr, Ba) phosphors were synthesized at low temperatures (550 degrees C) by the combustion method. The crystallinity of the phosphors was monitored by X-ray diffraction (XRD) and the morphology was examined by scanning electron microscope (SEM). Synthesis of phosphors, the effect of lanthanide concentrations on light emission intensity and duration investigated by using photoluminescence (PL) measurements. Narrow orange-red emissions from 500 to 750 nm in the PL spectra are assigned to D-5(0) -> F-7(j)) (j = 0,1,2,3,...) transitions of Eu3+ ion. In contrast, the broad luminescence band of the samples in the range of 400-500 rim are attributed to the 5d-4 f transitions of Eu3+ ion in the same host materials. Investigated the effects of radiation on the severity of the trap depths of these structures. The decay curves of these phosphors show how long the phosphors are attenuated. Thermoluminescence (TL) glow curves have been recorded from room temperature to 300 degrees C at a constant heating rate of 1 degrees C/s after preheat process at 130 degrees C for 10 s using lexsyg smart TL/OSL reader. Nd3+ trap levels can be thought of as the lanthanide element that causes long composition in the phosphorescence structure at room temperature

Influence of prenatal risks of pregnant women on mental symptoms [Gebelerin prenatal risklerinin ruhsal belirtilere etkisi]

Objective: In this study, it was aimed to investigate the influence of prenatal risk indicator scores of pregnant women on mental symptoms. Methods: This cross-sectional study was carried out with 142 pregnant women who were admitted to obstetrics clinic of a state hospital in İzmir province and who stated that they were not diag-nosed with any psychiatric diseases. A form questioning socio-demographic and obstetric characteristics of preg-nant women, Prenatal Risk Indicator aiming at determining risk of pregnant women and Brief Symptom Inventory (BSI) aiming at screening mental symptoms were used for data collection. Results: The most common risk fac-tors according to risk indicator were detected as experiencing urinary tract infection during the current pregnancy, being nulliparous, receiving late or insufficient prenatal care and inadequate weight gain and almost half of the pregnant women were found to be high risk. In addition, it was found that BSI scores were low, paranoid thought scores were high in high risk women and there was a positive correlation and phobic anxiety scores of all preg-nant women were equal. Conclusion: High risk pregnant women were detected to have paranoid thoughts and all pregnant women found to experience phobic anxiety equally