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121.
Ozan Unsalan Yusuf Erdogdu M. Tahir Gulluoglu 《Journal of Raman spectroscopy : JRS》2009,40(5):562-570
In this study, the experimental and theoretical results on the molecular structures of some flavonoid derivatives (Baicalein and Naringenin) are presented. The FT‐IR and FT‐Raman spectra of the compounds have been recorded together for the first time between 4000–400 cm−1 and 3500–5 cm−1 regions, respectively. The molecular geometry and vibrational wavenumbers of the compounds have been also calculated in their ground states by using ab initio HF and DFT/B3LYP functional with 6‐31G(d,p) basis set used in calculations. The calculations were utilized to the C1 symmetries of the molecules. All calculations were performed with Gaussian 98 software. The obtained vibrational wavenumbers and optimized geometric parameters were seen to be in good agreement with the experimental data. Scale factors have been used in order to compare how the calculated and experimental data are in agreement. Theoretical infrared intensities were also reported. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
122.
Yusuf Z. Umul 《Optics & Laser Technology》2009,41(3):285-933
A uniform version of the potential function of the Maggi-Rubinowicz boundary diffraction wave theory is obtained by using the large argument expansion of the Fresnel integral. The derived function is obtained for the problem of diffraction of plane waves by a circular edge. The results are plotted numerically. 相似文献
123.
The electronic structure and optical properties of one-electron Quantum Dot (QD) with and without an on-center impurity were investigated by assuming a spherically symmetric confining potential of finite depth. The energy eigenvalues and the state functions of QD were calculated by using a combination of Quantum Genetic Algorithm (QGA) and Hartree–Fock Roothan (HFR) method. We have calculated the binding energy for the states 1s,1p,1d,1f, oscillator strengths, the linear and third-order nonlinear optical absorption coefficients as a function of the incident photon energy and incident optical intensity for the 1s–1p, 1p–1d and 1d–1f transitions. The existence of the impurity has great influence on the optical absorption spectra and the oscillator strengths. Also we found that the magnitudes of the total absorption coefficients of the spherical QD increase for transitions between higher states. 相似文献
124.
Yusuf Zulykama 《Tetrahedron letters》2009,50(27):3892-3896
2-Bromomethyl-3-aryl-2-propenoic acids have been synthesized from Baylis-Hillman adducts derived from aromatic aldehydes and t-butyl acrylates as new precursors in MBH chemistry. Further triolides were synthesized by the cyclo-oligomerization of 2-bromomethyl-3-aryl-2-propenoic acids in the presence of Cs2CO3 demonstrating the synthetic utility of these motifs. 相似文献
125.
Yusuf Erdogdu M. Tahir Güllüoğlu Mustafa Kurt Şenay Yurdakul 《Journal of inclusion phenomena and macrocyclic chemistry》2009,64(3-4):341-355
We report the results of detailed experimental and theoretical studies on the molecular structure and vibrational spectra of metal(II) halide complexes of 1,3-bis(4-pyridyl)propane [M(N2C13H14)X2, where M represents Zn or Hg, and X represents Cl, Br, or I]. The FT–infrared spectra (FT-IR) and FT-Raman spectra of the metal complexes of the 1,3-bis(4-pyridyl)propane molecule in the powder form were recorded between the 400–4000 and 5–3500 cm?1 regions, respectively. The molecular geometry and vibrational frequencies of the metal complexes of 1,3-bis(4-pyridyl)propane in the ground state were calculated using density functional theory (B3LYP functional) with LANL2DZ and SDD as basis sets. The total energy distributions (TED) among the symmetry coordinates of the normal modes were computed for the low-energy structure of the molecules. Complete vibrational assignments based on the calculated TED values are given. 相似文献
126.
The direct molecular structure implementations of the gage-including atomic orbital (GIAO), individual gages for atoms in
molecules (IGAIM) and continuous set of gage transformations (CSGT) methods for calculating nuclear magnetic shielding tensors
at both the Hartree-Fock (HF) and density functional (B3LYP) levels of theory with 6-31G(d), 6-311G(d), 6-31++G(d,p), 6-311++G(d,p),
and 6-311++G(df,pd) basis sets are presented. Dependence on the 1H and 13C NMR chemical shifts on the choice of method and basis set have been investigated. Also, these chemical shifts of 2-aryl-1,3,4-oxadiazoles
5a–g have been performed related to dihedral angles (C4–C3–C2–O) of two conformers. The optimized molecular geometries and 1H and 13C chemical shift values of 2-aryl-1,3,4-oxadiazoles 5a–g in the ground state have been obtained. The linear correlation coefficients of 13C NMR chemical shifts for these molecules were given. The new nuclear magnetic shielding tensors of tetramethylsilane (TMS)
were calculated. The data of 2-aryl-1,3,4-oxadiazole derivatives display significant molecular structure and NMR analysis.
Also, these provide the basis for future design of efficient materials having the 1,3,4-oxadiazole core. 相似文献
127.
Reza Hosseinzadeh Mohammad Gheshlagi Rahele Tahmasebi Farnaz Hojjati 《Central European Journal of Chemistry》2009,7(1):90-95
The interaction of Procaine hydrochloride (PC) with cationic, anionic and non-ionic surfactants; cetyltrimethylammonium bromide
(CTAB), sodium dodecyl sulfate (SDS) and triton X-100, were investigated. The effect of ionic and non-ionic micelles on solubilization
of Procaine in aqueous micellar solution of SDS, CTAB and triton X-100 were studied at pH 6.8 and 29°C using absorption spectrophotometry.
By using pseudo-phase model, the partition coefficient between the bulk water and micelles, Kx, was calculated. The results showed that the micelles of CTAB enhanced the solubility of Procaine higher than SDS micelles
(Kx = 96 and 166 for SDS and CTAB micelles, respectively) but triton X-100 did not enhanced the solubility of drug because of
weak interaction with Procaine. From the resulting binding constant for Procaine-ionic surfactants interactions (Kb = 175 and 128 for SDS and CTAB surfactants, respectively), it was concluded that both electrostatic and hydrophobic interactions
affect the interaction of surfactants with cationic procaine. Electrostatic interactions have a great role in the binding
and consequently distribution of Procaine in micelle/water phases. These interactions for anionic surfactant (SDS) are higher
than for cationic surfactant (CTAB). Gibbs free energy of binding and distribution of procaine between the bulk water and
studied surfactant micelles were calculated.
相似文献
128.
In this report, we described the synthesis and characterization of a variety of diaminotriarylmethane derivatives with dimethylamino
functional groups. These compounds were synthesized by the tandem regio-selective electrophilic aromatic substitution reaction
of N,N-dimethylaniline with aryl aldehydes to form the corresponding diaminotriarylmethane compounds. In our strategy, Bi(NO3)3 was used as a catalyst under solvent free conditions to afford the desired products in good to excellent yields.
相似文献
129.
Bayram?KilicEmail author Sunay?Turkdogan Aykut?Astam Sümeyra?Seniha?Baran Mansur?Asgin Emre?Gur Yusuf?Kocak 《Journal of nanoparticle research》2018,20(1):11
Developing efficient and cost-effective photoanode plays a vital role determining the photocurrent and photovoltage in dye-sensitized solar cells (DSSCs). Here, we demonstrate DSSCs that achieve relatively high power conversion efficiencies (PCEs) by using one-dimensional (1D) zinc oxide (ZnO) nanowires and copper (II) oxide (CuO) nanorods hybrid nanostructures. CuO nanorod-based thin films were prepared by hydrothermal method and used as a blocking layer on top of the ZnO nanowires’ layer. The use of 1D ZnO nanowire/CuO nanorod hybrid nanostructures led to an exceptionally high photovoltaic performance of DSSCs with a remarkably high open-circuit voltage (0.764 V), short current density (14.76 mA/cm2 under AM1.5G conditions), and relatively high solar to power conversion efficiency (6.18%) . The enhancement of the solar to power conversion efficiency can be explained in terms of the lag effect of the interfacial recombination dynamics of CuO nanorod-blocking layer on ZnO nanowires. This work shows more economically feasible method to bring down the cost of the nano-hybrid cells and promises for the growth of other important materials to further enhance the solar to power conversion efficiency. 相似文献
130.