Yazar "Koylu, M. Z." seçeneğine göre listele

Listeleniyor 1 - 2 / 2
  • [ X ]
    Öğe
    Dynamic 1H NMR Studies of Schiff Base Derivatives
    (Springer, 2016) Koylu, M. Z.; Ekinci, A.; Boyukata, M.; Temel, H.
    The spin-lattice relaxation time T (1) and the spin-spin relaxation time T (2) of two Schiff base derivatives, N,N'-ethylenebis(salicylidene)-1,2-diaminoethane (H2L1) and N,N'-ethylenebis (salicylidene)-1,3-diaminopropane (H2L2), in DMSO-d(6) solvent were studied as a function of temperature in the range of 20-50A degrees C using a Bruker Avance 400.132 MHz H-1 NMR spectrometer. Based on the activation energy (E (a)) and correlation time (tau(c)), we believe that the Schiff base derivatives perform a molecular tumbling motion.
  • [ X ]
    Öğe
    Proton NMR Relaxation in Albumin Solution Doped with Mn(II)
    (Springer Wien, 2009) Yilmaz, A.; Koylu, M. Z.; Uysal, E.
    The aim of this study is to obtain further information about the source of proton relaxation in the Mn(II)-human serum albumin complex. For this purpose, proton relaxation rates in albumin solutions 1/T(1) and 1/T(2) were measured versus increasing amounts of manganese [Mn(t)]. The fractions of manganese bound to albumin [Mn(b)] and free manganese [Mn(f)] were then determined from proton relaxation rate enhancement data. Paramagnetic contributions of bound manganese to the observed relaxation rates (1/T(1p)*)(b) and (1/T(2p)*)(b) were also determined. Finally, the (1/T(2p)*)(b)/(1/T(1p)*)(b) ratio was used in a derived equation to estimate an effective correlation time tau. Mean tau value of the complex was found to be in the order of 3 ns, while the hydration number of bound manganese q was estimated to be about 4. The 1/tau was found to be the sum of the inverse values of rotational correlation time 1/tau(r), mean residence time of water in hydration spheres of the complex 1/tau(m), and longitudinal electronic relaxation time of manganese 1/tau(s) in the complex. In conclusion, the relaxation mechanism in albumin solutions containing Mn(II) can be interpreted through dipolar and scalar interactions modulated by tau(r), tau(m) and tau(s). This analysis enables one to get reasonable figures for the tau(r) and q of Mn(II) in albumin solution.