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Öğe Ab-initio and DFT methodologies for computing hyperpolarizabilities and susceptibilities of highly conjugated organic compounds for nonlinear optical applications(ELSEVIER SCIENCE BV, 2016) Karakas, A.; Karakaya, M.; Ceylan, Y.; El Kouari, Y.; Taboukhat, S.; Boughaleb, Y.; Sofiani, Z.In this talk, after a short introduction on the methodologies used for computing dipole polarizability (alpha), second and third-order hyperpolarizability and susceptibility; the results of theoretical studies performed on density functional theory (DFT) and ab-initio quantum mechanical calculations of nonlinear optical (NLO) properties for a few selected organic compounds and polymers will be explained. The electric dipole moments (mu) and dispersion-free first hyperpolarizabilities (beta) for a family of azo-azulenes and a styrylquinolinium dye have been determined by DFT at B3LYP level. To reveal the frequency dependent NLO behavior, the dynamic a, second hyperpolarizabilities (gamma), second (chi((2))) and third-order (chi((3))) susceptibilites have been evaluated using time-dependent HartreeFock (TDHF) procedure. To provide an insight into the third-order NLO phenomena of a series of pyrrolo-tetrathiafulvalene-based molecules and pushpull azobenzene polymers, two-photon absorption (TPA) characterizations have been also investigated by means of TDHF. All computed results of the examined compounds are compared with their previous experimental findings and the measured data for similar structures in the literature. The one-photon absorption (OPA) characterizations of the title molecules have been theoretically obtained by configuration interaction (CI) method. The highest occupied molecular orbitals (HOMO), the lowest unoccupied molecular orbitals (LUMO) and the HOMO-LUMO band gaps have been revealed by DFT at B3LYP level for azo-azulenes, styrylquinolinium dye, push-pull azobenzene polymers and by parametrization method 6 (PM6) for pyrrolo-tetrathiafulvalene-based molecules. (C) 2016 Elsevier B.V. All rights reserved.Öğe Computational studies on linear, second and third-order nonlinear optical properties of novel styrylquinolinium dyes(ELSEVIER, 2016) Karakas, A.; Karakaya, M.; Taser, M.; Ceylan, Y.; Gozutok, A.; Arof, A. K.; El Kouari, Y.The electric dipole moments (mu), static dipole polarizabilities (alpha) and first hyperpolarizabilities (beta) of styrylquinolinium dyes, D8 and D21, have been computed by density functional theory (DFT). The one photon absorption (OPA) characterizations have been investigated using UV-vis spectroscopy and further interpreted using computational chemistry. The time-dependent Hartree-Fock (TDHF) method has been used to describe the dynamic dipole polarizabilities, dynamic second-order and also static and dynamic third-order nonlinear optical (NLO) properties. D8-D21 have rather high beta and second hyperpolarizabilities (gamma). The highest occupied molecular orbitals (HOMO), the lowest unoccupied molecular orbitals (LUMO) and the HOMO-LUMO band gaps for D8-D21 have been evaluated by DFT. (C) 2016 Elsevier B.V. All rights reserved.Öğe Diagnostic and control of linear and nonlinear optical effects in selected self-assembled metallophthalocyanine chlorides nanostructures(ELSEVIER SCI LTD, 2018) Zawadzka, A.; Waszkowska, K.; Karakas, A.; Plociennik, P.; Korcala, A.; Wisniewski, K.; Karakaya, M.In this paper we described a new self-assembly phenomenon of the metallophthalocyanine chlorides nanostructures and its influence on the linear optical properties as well as the Second Harmonic Generation process. The self-assembly phenomenon were achieved through an annealing process carried out immediately after the deposition process. The studied nanostructures were subjected to the annealing process for 24 h and the temperature of the process was equal to 525 K. We discussed experimental results and theoretical calculations of structural, linear and nonolinear optical properties for aluminum and gallium phthalocyanine chlorides. The linear and second-order nonlinear optical properties for these compounds were investigated at microscopic and macroscopic levels. The electric dipole moments and dispersion-free first hyperpolarizabilities were determined by quantum chemical calculations based on Density Functional Theory. Ab-initio quantum mechanical calculations (time-dependent Hartree-Fock method) for the studied metallophthalocyanine chlorides were carried out to compute the frequency-dependent first hyperpolarizabilities and second-order susceptibilities at the wavelengths used in SHG measurements. Our results shed light on the linear and nonlinear optical properties of the nanostructures. The results showed that second harmonic signal is strong and polarized, and this polarizing effect was achieved by controlling the arrangement of the molecules inside the formed nanostructures. Our results also reveal potential application of the nanostructures not only for nonlinear optics but also for thermal sensor devices.Öğe Differential Scanning Calorimetry Analysis of Goat Fats: Comparison of Chemical Composition and Thermal Properties(SPRINGER, 2009) Yilmaz, Mustafa Tahsin; Karakaya, M.The physical-chemical properties, fatty acid composition and thermal properties of goat subcutaneous (SF), tallow (TF) and intestinal (IF) fats were determined. SF differed from other fat types with respect to its lower melting (41.6 A degrees C), lower saponification (190.3 mg KOH/g) and higher iodine (40.4) values as compared to those of other fats. Goat fat types contained palmitic acid (C(16:0)), stearic acid (C(18:0)), oleic acid (C(18:1 omega 9)) and linoleic acid (C(18:2 omega 6)) as the major components of the fatty acid composition (23.06-23.52, 22.95-39.03, 21.94-36.16 and 1.96-2.22%, respectively). A differential scanning calorimetry (DSC) study revealed that two characteristic peaks were detected in both crystallization and melting curves. Major peaks (T (peak)) of TF and IF were similar and determined as 34.02-35.24 and 9.95-10.72 A degrees C, respectively for the crystallization peaks and 15.11-18.26 and 50.70-52.76 A degrees C, respectively for the melting peaks in the DSC curves; but those of SF (27.14 and 4.36 A degrees C for crystallization peaks and 8.39 and 44.93 A degrees C for melting peaks) differed remarkably from those of other fat types.Öğe The effect of carcass part and packaging method on the storage stability of mechanically deboned chicken meat(WILEY, 2008) Ozkececi, R. B.; Karakaya, M.; Yilmaz, M. T.; Saricoban, C.; Ockerman, H. W.Mechanically deboned chicken frame meat (MDCFM) and mechanically deboned chicken neck meat (MDCNM) samples were obtained from mechanically deboned chicken meat (MDCM) by a Beehive separator MDCM was vacuum- or air-packed and stored frozen for 4, 8, 12, 16, 20 and 24 weeks. The effects of packing and storage time of MDCFM and MDCNM on free fatty acid (FFA), peroxide and TBA values were determined, and the interaction effects between part of carcass (frame or neck), storage form (either vacuum- or air-packed) and storage time on these parameters were investigated. The significant (P < 0.001; 0.05) effect of storage time on pH, FFA, peroxide and TBA values was determined. Part of carcass and storage form were the factors with the greatest effect (P < 0.001) on TBA values, followed by the effect of storage time. In general, neck meats were more stable than frame meats with regard to TBA values during storage period; however, these values increased with prolonged storage time. Among the interactions, TBA values were highly influenced by carcass part x storage form. Vacuum-packed MDCNM could be stored for up to 24 weeks within normal limitations with respect to the stability of the parameters studied.Öğe Growth performance and quality properties of meat from broiler chickens reared under different monochromatic light sources(TAYLOR & FRANCIS LTD, 2009) Karakaya, M.; Parlat, S. S.; Yilmaz, M. T.; Yildirim, I.; Ozalp, B.1. Quality properties of breast and drumstick muscles of female broiler chickens reared under different light sources were evaluated using a total of 480 female chicks (Ross 308). 2. After hatch, the chicks were randomly divided into three lighting treatment groups: control (daylight; mini incandescent lamps), G-B lighting group (green light monochromatic (MC) lamps for first 3 weeks switching to blue MC lamps for remaining 3 weeks), G-GB mixed lighting group (Green MC light for first 3 weeks, switching to Green MC light + Blue MC light mixture for remaining 3 weeks). 3. Feed consumption, body weight and total muscle weight values of the muscles from G-B and G-GB mix lighting groups were significantly higher than those of incandescent (control) lighting groups. 4. The breast and drumstick muscles from control lighting groups had a lower pH and water-holding capacity, but higher cooking loss values than those from G-B and G-GB mix lighting groups. The muscles from G-GB mix lighting groups exhibited the softer structure than those from other lighting groups. 5. We suggest that G-B or G-GB mix lighting during the rearing period of female broilers would improve body and muscle growth and then meat quality properties.Öğe One-photon Absorption Characterizations, Dipole Polarizabilities and Second Hyperpolarizabilities of Chlorophyll a and Crocin(SCIENDO, 2018) Karakas, A.; Ceylan, Y.; Karakaya, M.; Taser, M.; Terlemez, B. B.; Eren, N.; El Kouari, Y.The dispersion-free dipole polarizability (alpha) computations for chlorophyll a (1) and crocin (2) have been achieved by density functional theory (DFT) at B3LYP/ 6-31G(d) level. The measured one-photon absorption (OPA) wavelengths are quite consistence with the theoretically obtained values. Ab-initio quantum chemical calculations (time-dependent Hartree-Fock (TDHF)) have been implemented to reveal the static second hyperpolarizabilities (gamma) and dynamic dipole polarizabilities of the title molecules. The examined compounds display gamma with non-zero values, introducing their third-order nonlinear optical (NLO) phenomena. The first and second frontier molecular orbitals of the investigated molecules have been also derived from DFT.Öğe Quantum chemical calculations and experimental studies of third-order nonlinear optical properties of conjugated TTF-quinones(ELSEVIER SCIENCE BV, 2013) Karakas, A.; Migalska-Zalas, A.; El Kouari, Y.; Gozutok, A.; Karakaya, M.; Touhtouh, S.To investigate microscopic third-order nonlinear optical (NLO) behaviour of two tetrathiafulvalene (TTF) derivatives, TTF-diquinone triad (1) and TTF-monoquinone dyad (2), we have computed both dispersion-free and also dispersion of dipole polarizabilities (alpha) and third-order hyperpolarizabilities (gamma) at 532 nm wavelength using time-dependent Hartree-Fock (TDHF) method. The one-photon absorption (OPA) characterizations of the title molecules have been theoretically obtained by means of configuration interaction (CI) method with all doubly occupied molecular orbitals. We have also calculated the dynamic third-order susceptibilities (chi((3))) using the TDHF method. Our theoretical results on the maximum OPA wavelengths, third-order susceptibilities and corresponding microscopic NLO responses are in good agreement with the previous experimental observations of the examined TTF-based molecules. The highest occupied molecular orbitals (HOMO), the lowest unoccupied molecular orbitals (LUMO) and the HOMO-LUMO band gaps for I and 2 have been evaluated by density functional theory (DFT) quantum mechanical calculations at B3LYP/6-31 G(d,p) level. (C) 2013 Elsevier B.V. All rights reserved.Öğe Second and third-order nonlinear optical behavior of natural pigment: chlorophyll and crocin(SPRINGER HEIDELBERG, 2017) Karakas, A.; Karakaya, M.; Taser, M.; Ceylan, Y.; Arof, A. K.; El Kouari, Y.; Sahraoui, B.To provide an insight into the microscopic second and third-order nonlinear optical (NLO) behavior of chlorophyll a and crocin, we have computed the electric dipole moments (mu), dispersion-free first hyperpolarizabilities (beta), frequency-dependent first and second (gamma) hyperpolarizabilities at 1064 nm wavelength area using time-dependent Hartree-Fock (TDHF) method. According to ab-initio calculation results, the examined compounds exhibit first and second hyperpolarizabilities with non-zero values, implying second and third-order NLO phenomena.Öğe Second-order nonlinearities of anionic 3-dicyanomethylen-5,5-dimethyle-1-[2-(4-hydroxyphenyl)ethenyl)]-cyclohexene(ELSEVIER SCIENCE BV, 2016) Karakaya, M.; Karakas, A.; Taser, M.; Wolska, N.; Arof, A. K.; Sahraoui, B.Due to the connecting one pi -conjugated group with the two backside donor and acceptor groups, anionic 3-dicyanomethylen-5,5-dimethyle-1-[2-(4-hydroxyphenyl)ethenyl)]-cyclohexene (1) might possess nonlinear optical (NLO) properties. To estimate the potential for second-order NLO behaviour; the electric dipole moments and dispersion-free dipole polarizabilities and first hyperpolarizabilities have been determined by density functional theory (DFT) at B3LYP/6-31++G(d, p) level. Quantum mechanical calculations using time-dependent Hartree-Fock (TDHF) procedure have been utilized to evaluate frequency-dependent second-order nonlinearities of 1. The one-photon absorption (OPA) characterization of 1 has been theoretically obtained by means of configuration interaction (CI) with 6-31G basis set. Our theoretical results on the maximum OPA wavelength, second-order susceptibilities and corresponding microscopic NLO responses are accorded with the previous experimental observations of the investigated compound. The highest occupied molecular orbitals, the lowest unoccupied molecular orbitals and the HOMO-LUMO band gaps for 1 have been also examined by DFT/B3LYP method. (C) 2016 The Authors. Published by Elsevier Ltd.Öğe Structural characterization and second-order nonlinear optical behavior of metal complexes of ferrocene derivative(MAIK NAUKA/INTERPERIODICA/SPRINGER, 2019) Deveci, P.; Taner, B.; Özcan, E.; Kılıç, Z.; Karakaya, M.; Karakas, A.In this manuscript, a ferrocene-linked vic-dioxime ligand (LH2) and its metal complexes [Ni(LH)(2), Cu(LH)(2), Co(LH)(2)(H2O)(2), Cd(LH)(H2O)(Cl), and Zn(LH)(H2O)(Cl)] are synthesized, and their structures are studied by spectral methods. Redox behavior of the compounds is studied by cyclic voltammetry (CV). For approaching microscopic second-order nonlinear optical (NLO) behavior of the synthesized ligand and its diamagnetic Cd(II), Zn(II), Ni(II) complexes, the electric dipole moment , static dipole polarizability , and first hyperpolarizability values are computed using ab-initio quantum chemical procedure [finite field (FF)]. The accumulated data indicate that the compounds exhibit non-zero quadratic hyperpolarizability tensor components, implying microscopic NLO phenomena. The HOMOs, LUMOs and the HOMOLUMO band gaps for first and second frontier orbitals of LH2 ligand and its Cd(II), Zn(II), Ni(II) complexes are evaluated by means of the Hartree-Fock (HF) method.Öğe Technological and textural properties of spent chicken breast, drumstick and thigh meats as affected by marinating with pineapple fruit juice(TAYLOR & FRANCIS LTD, 2019) Kadıoglu, P.; Karakaya, M.; Unal, K.; Babaoglu, A. S.1. This study was conducted to determine the effects of pineapple fruit juice at different marination times (0, 40, 80, 120 and 160 min) on pH, water holding capacity (WHC), cooking loss (CL) and colour (L*, a*, b*, hue angle and chroma) properties of breast, drumstick and thigh meats from spent hens. Textural properties (razor shear force and shear energy) and sensory analyses of the samples were tested. 2. With increasing marination time, there was a decrease in pH and WHC values, and an increase in CL values. However, marination treatment with pineapple fruit juice significantly affected the textural measurement of all the meat muscles compared with the control group. 3. Razor shear force and shear energy were lower when marination was performed for 160 min. Colour analyses showed that marination for 80 min resulted in significantly increased L*, a* and b* values. The samples marinated for longer times were most preferable, according to the tenderness scores assigned by the panellists.Öğe Theoretical diagnostics of second and third-order hyperpolarizabilities of several acid derivatives(DE GRUYTER POLAND SP ZOO, 2019) Karakas, A.; Ceylan, Y.; Karakaya, M.; Taser, M.; Terlemez, B. B.; Eren, N.; El Kouari, Y.The density functional theory (DFT) at B3LYP/6-31G(d) level has been utilized to achieve the electric dipole moment (mu), static dipole polarizability (alpha) and first hyperpolarizability (beta) values for ferulic acid (1) and chenodeoxycholic acid (2). The time-dependent Hartree-Fock (TDHF) technique as a powerful quantum chemical method has been implemented to reveal the dynamic alpha, beta and third-order hyperpolarizabilities (gamma) of the examined compounds. Our computational conclusions have been compared with the results of similar materials in the literature. The first and second frontier molecular orbitals (MOs) and their band gaps have also been investigated by means of DFT.Öğe Thermal analysis of lipids isolated from various tissues of sheep fats(SPRINGER, 2010) Yilmaz, M. T.; Karakaya, M.The physical-chemical properties and fatty acid composition of sheep subcutaneous, tallow, intestinal, and tail fats were determined. Sheep fat types contained C(16:0), C(18:0), and C(18:1) as the major components of fatty acid composition (19.56-23.40, 20.77-29.50, 32.07-38.30%, respectively). Differential scanning calorimetry (DSC) study revealed that two characteristic peaks were detected in both crystallization and melting curves. Major peaks (T (peak)) of tallow and intestinal fats were similar and determined as 31.25-24.69 and 7.44-3.90 A degrees C, respectively, for crystallization peaks and 15.36-13.44 and 45.98-44.60 A degrees C, respectively, for melting peaks in DSC curves; but those of tail fat (18.29 and -2.13 A degrees C for crystallization peaks and 6.56 and 33.46 A degrees C for melting peaks) differed remarkably from those of other fat types.
