Temel Mühendislik Ana Bilim Dalı

Permanent URI for this communityhttps://hdl.handle.net/20.500.12416/1818

Browse

Now showing 1 - 4 of 4

Citation - WoS: 5
Citation - Scopus: 5
Determination of trapping parameters of Tl2In2S3Se layered single crystal by thermoluminescence
(Wiley-v C H verlag Gmbh, 2018) Guler, Ipek; Güler, İpek; Gasanly, Nizami; 101531; Ortak Dersler Bölümü
Thermoluminescence (TL) measurements are performed to evaluate the trap states in Tl2In2S3Se layered single crystals. TL experiments are conducted with varying temperature from 10 to 300 K and warming rates from 0.2 to 1.0 K s(-1). From the analysis of both initial rise and curve fitting methods, the activation energy of the traps is obtained as 23 meV. The Chen's method is also used to find activation energy. By means of this technique, the activation energy of the TL glow curve is calculated as 25 meV. From both Chen's method and curve fitting method, the existence of mixed order of kinetics in Tl2In2S3Se crystal is found. The cross section to capture of the trap center is found out from the results of curve fitting method. The trap distribution of the crystals is investigated with different temperatures of illumination at a constant warming rate of 0.8 K s(-1). The temperatures of illumination change from 10 to 22 K. As a result of the increase in temperatures of illumination, the peak maximum values move to higher temperatures and intensity of the TL curves decreases. This behavior shows us that quasicontinuous traps distribution is present in Tl2In2S3Se layered single crystals.
Citation - WoS: 3
Citation - Scopus: 3
N-phosphorylation of pyrroles: An intramolecular migration reaction
(Pergamon-elsevier Science Ltd, 2018) Tasgin, Dilek Isik; Taşgın, Dilek; Unaleroglu, Canan; Ortak Dersler Bölümü
A new synthetic method is reported for the N-phosphorylation of pyrroles via intramolecular migration of a phosphonate diester group. The reaction proceeds under mild conditions and produces N-phosphorylated pyrrole derivatives in moderate to good yields. (C) 2018 Elsevier Ltd. All rights reserved.
Citation - WoS: 5
Citation - Scopus: 6
Ring annulation versus alkylation of pyrrole with alpha-phosphoryl-alpha,beta-unsaturated ketones
(Pergamon-elsevier Science Ltd, 2016) Tasgin, Dilek Isik; Unaleroglu, Canan; 16910
In this study; novel aryl, heteroaryl, pyrrolyl and phosphoryl groups containing pyrrolizines were synthesized by the ring annulation reaction of aryl or heteroaryl substituted alpha-phosphoryl-alpha,beta-unsaturated ketones with pyrrole under mild reaction conditions. This domino reaction involves scandium triflate catalyzed addition of pyrrole to the double bond of alpha-phosphoryl-alpha,beta-unsaturated ketones, carbonyl group and finally ring annulation sequences. The presented work provided a convenient way for the synthesis of novel bispyrrolic compounds. (C) 2016 Elsevier Ltd. All rights reserved.
Citation - WoS: 13
Citation - Scopus: 14
Structural and Optical Properties of Ga2Se3 Crystals by Spectroscopic Ellipsometry
(Springer, 2019) Guler, I.; Güler, İpek; Isik, M.; Gasanly, N. M.; Gasanova, L. G.; Babayeva, R. F.; 101531; Ortak Dersler Bölümü
Optical and crystalline structure properties of Ga2Se3 crystals were analyzed utilizing ellipsometry and x-ray diffraction (XRD) experiments, respectively. Components of the complex dielectric function (epsilon=epsilon(1)+i epsilon(2)) and refractive index (N=n+ik) of Ga2Se3 crystals were spectrally plotted from ellipsometric measurements conducted from 1.2eV to 6.2eV at 300K. From the analyses of second-energy derivatives of epsilon(1) and epsilon(2), interband transition energies (critical points) were determined. Absorption coefficient-photon energy dependency allowed us to achieve a band gap energy of 2.02eV. Wemple and DiDomenico single effective oscillator and Spitzer-Fan models were accomplished and various optical parameters of the crystal were reported in the present work.

Browse

Browsing Temel Mühendislik Ana Bilim Dalı by WoS Q "Q3"