The ground state hydrogen conformations and vibrational analysis of 3-deazauracil(3DAU)and 6-azauracil(6AU)tautomers(4-enol and 2,4-diol forms)have been calculated using ab initio Hartree-Fock(HF)and density functiona...The ground state hydrogen conformations and vibrational analysis of 3-deazauracil(3DAU)and 6-azauracil(6AU)tautomers(4-enol and 2,4-diol forms)have been calculated using ab initio Hartree-Fock(HF)and density functional theory(B3LYP)methods with 6-311++G(d,p)basis set level.The calculations have shown that the most probably preferential tautomer of 3DAU and 6AU are the 4-enol form,which gives best fit to the corresponding experimental data.The ground state conformer of the 2,4-diol form has two O—H bonds which are oriented externally and internally(to the N—H bond).The vibrational analyses of the ground state conformer of each tautomeric form of 3DAU and 6AU were done and their optimized geometry parameters(bond lengths and bond angles)were given.Furthermore,from the correlations values it was concluded that the B3LYP method is superior to the HF method for both the vibrational frequencies and the geometric parameters.展开更多
Spectra of KX-rays emitted from pure 3 dtransition metals and their oxide and sulfate compounds were measured using a single crystal wavelength dispersive X-ray spectroscopy(WDXRF).The measurements were performed usin...Spectra of KX-rays emitted from pure 3 dtransition metals and their oxide and sulfate compounds were measured using a single crystal wavelength dispersive X-ray spectroscopy(WDXRF).The measurements were performed using a ZSX-100 esequential spectrometer equipped with an RhX-ray tube operated.An accurate analytical representation of each line was obtained by a fit to a Lorentz function.The spectra were analyzed in order to examine the KX-ray peak parameters such as asymmetry index,peak energy and relative intensity ratios.The energy shifts and relative intensities weredetermined tobetter understand the chemical effect.展开更多
The measurement of K shell fluorescence parameters is an easy and practical way to investigate the electronic structures of elements in alloys,compounds or complexes.Since the number of valence electrons will change t...The measurement of K shell fluorescence parameters is an easy and practical way to investigate the electronic structures of elements in alloys,compounds or complexes.Since the number of valence electrons will change the screening effect,the measured parameters will be affected from the changes.In this study,the measured parameters were investigated for sulphur element according to the number of CH_2 groups.For the experimental measurements,the samples were excited by 59.5keVγrays from a 241 Am annular radioactive source.The emitted K X-rays from the samples were counted by ab Ultra-LEGe detector with a resolution of 150 eV at 5.9keV.展开更多
基金supported by Research Fund of the Erzincan University(Project no:FEN-A-150615-0149)
文摘The ground state hydrogen conformations and vibrational analysis of 3-deazauracil(3DAU)and 6-azauracil(6AU)tautomers(4-enol and 2,4-diol forms)have been calculated using ab initio Hartree-Fock(HF)and density functional theory(B3LYP)methods with 6-311++G(d,p)basis set level.The calculations have shown that the most probably preferential tautomer of 3DAU and 6AU are the 4-enol form,which gives best fit to the corresponding experimental data.The ground state conformer of the 2,4-diol form has two O—H bonds which are oriented externally and internally(to the N—H bond).The vibrational analyses of the ground state conformer of each tautomeric form of 3DAU and 6AU were done and their optimized geometry parameters(bond lengths and bond angles)were given.Furthermore,from the correlations values it was concluded that the B3LYP method is superior to the HF method for both the vibrational frequencies and the geometric parameters.
基金the Scientific and Technological Research Council of Turkey (TUBITAK), under the project No. 10GT045
文摘Spectra of KX-rays emitted from pure 3 dtransition metals and their oxide and sulfate compounds were measured using a single crystal wavelength dispersive X-ray spectroscopy(WDXRF).The measurements were performed using a ZSX-100 esequential spectrometer equipped with an RhX-ray tube operated.An accurate analytical representation of each line was obtained by a fit to a Lorentz function.The spectra were analyzed in order to examine the KX-ray peak parameters such as asymmetry index,peak energy and relative intensity ratios.The energy shifts and relative intensities weredetermined tobetter understand the chemical effect.
基金The financial support from research foundation of Mustafa Kemal University(grant no:13121)is also gratefully acknowledged
文摘The measurement of K shell fluorescence parameters is an easy and practical way to investigate the electronic structures of elements in alloys,compounds or complexes.Since the number of valence electrons will change the screening effect,the measured parameters will be affected from the changes.In this study,the measured parameters were investigated for sulphur element according to the number of CH_2 groups.For the experimental measurements,the samples were excited by 59.5keVγrays from a 241 Am annular radioactive source.The emitted K X-rays from the samples were counted by ab Ultra-LEGe detector with a resolution of 150 eV at 5.9keV.
