197,607 research outputs found
Otolith characteristics of species, subspecies, and populations of Aphanius Nardo, 1827 (Teleostei, Cyprinodontiformes) from Anatolia (Turkey)
No full textSchulz-Mirbach, Tanja, Reichenbacher, Bettina, Yildirim, M. Zeki, Atalay, M. Altuğ (2006): Otolith characteristics of species, subspecies, and populations of Aphanius Nardo, 1827 (Teleostei, Cyprinodontiformes) from Anatolia (Turkey). Journal of Natural History 40 (27-28): 1687-1705, DOI: 10.1080/00222930600964498, URL: http://dx.doi.org/10.1080/0022293060096449
A theoretical study on N-phenyl-N '-(2-thienylmethylene)hydrazine
No full textThe molecular geometry and vibrational frequencies of N-phenyl-AP-(2-thienyimethylene)hydrazine (C11H10N2S) have been calculated using Hartree-Fock and density functional method (B3LYP) with 6-31G(d) basis set. The optimized geometric bond lengths and angles obtained using HF and DFr (B3LYP) are in agreement with the experimental data. B3LYP method seems to be appropriate than HF method for the calculation of vibrational frequencies and geometrical parameters of the (C11H10N2S) compound. (c) 2006 Elsevier B.V. All rights reserved
Determination of the optical constants of 2-amino-5-phenyl-1,3,4-thiadiazole by Hartree-Fock and density functional method (B3LYP)
No full textThe optical constants (real and imaginary refractive index) and complex dielectric constants of 2-amino-5-phenyl-1,3,4-thiadiazole between 4000 and 400 cm(-1) at 25 degrees C were calculated using the Hartree-Fock and density functional method (B3LYP) and are reported for the first time. The Cauchy parameters obtained from the refractive index spectrum were found to be A = 9.870, B = 2.85 X 10(-5) cm(2) and C = 8.86X 10(-12) cm(4) for experimental results and A = 15.369, B = 3.19 X 10-5 cm(2) and C = 1.49 X 10(-12) cm(4) for HF model and A = 9.871, B = 1.73 X 10(-5) cm(2) and C= 9.24 X 10(-13) cm(4) for B3LYP model, The real and imaginary parts of the complex dielectric constant of the compound were calculated. The real part of the dielectric constant is higher than the imaginary part. The variation of the dielectric constant with photon energy indicates that some interactions between photons and electrons in the film are produced in the investigated energy range. These interactions are observed on the shapes of the real and imaginary parts of the dielectric constant and they cause formation of peaks in dielectric spectra. As a result, the optical constants obtained by using HF and DFT (B3LYP) methods show the best agreement with the experimental data. (c) 2005 Elsevier B.V. All rights reserved.https://doi.org/10.1016/j.molstruc.2005.07.02
Structural and Dielectrical Properties of MnO2-V2O5-SnO Mixed Oxides System at 1023 K
No full textThe different concentrations of the composites were prepared by mixing the 80 mass % of the base material MnO2 with 10 mass % V2O5 and 10 mass % SnO (sample A), and with 15 mass % V2O5 and 5 mass % SnO (sample 13), respectively. The composite materials were examined using Fourier Transform Infrared (FTIR), X-Ray Diffraction (XRD), ac impedance and dc techniques. The XRD and FTIR numbers show the composites consist of the mixture of different phases, Mn2V2O7, Mn2O3 and SnO2. During reaction at high temperature, it is found that tin (II) oxidizes to tin (IV) and Mn (IV) reduce's to Mn (III). The conductivities of the composites were found to be within the semiconducting region (similar to 3.67x10(-7) S cm(-1). (x10(2) S m(-1)) for sample A and similar to 7.33x10(-7) S cm(-1) (x10(2) S m(-1)) for sample 13). The dielectric constants were calculated to be 59 for sample A and 36 for sample B, at similar to 100 Hz, respectively
The molecular structure and vibrational spectra of 1-amino-5-benzoyl-4-phenylpyrimidin-2(1H) by Hartree-Fock and density functional methods
No full textThe molecular structure and vibrational spectra of 1-amino-5-benzoyl-4-phenylpyrimidin-2(1H) (C17H13N3O2) have been investigated by Hartree-Fock and density functional method using standard B3LYP with 6-31G(d) basis set. The calculated results of the geometric bond lengths and bond angles obtained by using HF and DFT (B3LYP) are in very good agreement with the experimental values. Comparison of the observed fundamental vibrational frequencies of 1-amino-5-benzoyl-4-phenylpyrimidin-2(1H) (C17H13N3O2) and calculated results by density functional B3LYP and Hartree-Fock methods indicate that B3LYP is superior to the scaled Hartree-Fock approach for molecular vibrational problems. (c) 2006 Elsevier B.V.. All rights reserved
Mechanisms with costly knowledge
No full textThesis: S.M., Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science, 2016.Cataloged from PDF version of thesis.Includes bibliographical references (pages 18-21).We propose investigating the design and analysis of game theoretic mechanisms when the players have very unstructured initial knowledge about themselves, but can refine their own knowledge at a cost. We consider several set-theoretic models of "costly knowledge". Specifically, we consider auctions of a single good in which a player i's only knowledge about his own valuation, [theta]i, is that it lies in a given interval [a, b]. However, the player can pay a cost, depending on a and b (in several ways), and learn a possibly arbitrary but shorter (in several metrics) sub-interval, which is guaranteed to contain [theta]i. In light of the set-theoretic uncertainty they face, it is natural for the players to act so as to minimize their regret. As a first step, we analyze the performance of the second-price mechanism in regret-minimizing strategies, and show that, in all our models, it always returns an outcome of very high social welfare.by Atalay M. Ileri.S.M
Figure 7 in Otolith characteristics of species, subspecies, and populations of Aphanius Nardo, 1827 (Teleostei, Cyprinodontiformes) from Anatolia (Turkey)
No full textFigure 7. Left sagittae of Aphanius villwocki (a–i) and A. asquamatus (j–m), except (m) right sagitta, mirrored. Localities (A. villwocki): upper Sakarya River basin (a–g), Lake Çavuşçu (h), Adakasım (i). (a–c, i–k) Females; (d– h, l, m) males.Published as part of <i>Schulz-Mirbach, Tanja, Reichenbacher, Bettina, Yildirim, M. Zeki & Atalay, M. Altuğ, 2006, Otolith characteristics of species, subspecies, and populations of Aphanius Nardo, 1827 (Teleostei, Cyprinodontiformes) from Anatolia (Turkey), pp. 1687-1705 in Journal of Natural History 40 (27-28)</i> on page 1699, DOI: 10.1080/00222930600964498, <a href="http://zenodo.org/record/10092220">http://zenodo.org/record/10092220</a>
An infrared spectroscopic study on a divalent metal salt of p-aminobenzoic acid [ABA(Mg)] tetracyanonickelate
No full textInfrared spectra of MLNi (CN)(4) [M=Mn, Fe, Co, Ni, Zn or Cd and L= Divalent metal of p-Aminobenzoic Acid or ABA (Mg)] are reported. Their structure consists of polymeric layers of [M-Ni(CN)(4)](a) with the divalent metal of p-aminobenzoic acid [ABA(Mg)] molecules bound directly to the metal (M)
Molecular structure and vibrational and chemical shift assignments of 5-(2-Hydroxyphenyl)-4-(p-tolyl)-2,4-dihydro-1,2,4-triazole-3-thione by DFT and ab initio HF calculations
No full textThe molecular geometry, vibrational frequencies, gauge including atomic orbital (GIAO) (1)H and (13)C chemical shift values and several thermodynamic parameters of 5-(2-Hydroxyphenyl)-4-(p-tolyl)-2,4-dihydro-1,2,4-triazole-3-thione in the ground state have been calculated by using the Hartree-Fock (HF) and density functional method (DFT/B3LYP) with 6-31G(d), 6-31 + G(d,p) and LANL2DZ basis sets. The results of the optimized molecular structure are presented and compared with the experimental X-ray diffraction. The computed vibrational frequencies are used to determine the types of molecular motions associated with each of the experimental bands observed. Also, calculated (1)H chemical shift values compared with the experimental ones. The data of the title compound display significant molecular structure and IR, NMR analysis provide the basis for future design of efficient materials having the of 1,2,4-triazole core
Molecular structure and vibrational and chemical shift assignments of 3-(2-Hydroxyphenyl)-4-phenyl-1H-1,2,4-triazole-5-(4H)-thione by DFT and ab initio HF calculations
No full textThe molecular geometry, vibrational frequencies, gauge including atomic orbital (GIAO) H-1 and C-13 chemical shift values and several thermodynamic parameters of 3-(2-Hydroxyphenyl)-4-phenyl-1H-1,2,4-triazole-5-(4H)-thione in the ground state have been calculated by using the Hartree-Fock (HF) and density functional methods (BLYP and B3LYP) with 6-31G(d) basis set. The results of the optimized molecular structure are presented and compared with the experimental X-ray diffraction. The molecule contains one O-H center dot center dot center dot N and one C-H center dot center dot center dot pi (phenyl) intramolecular interactions. The computed vibrational frequencies are used to determine the types of molecular motions associated with each of the experimental bands observed. Data of the title compound display significant structure-correlation and provide the basis for future design of efficient materials having the derivatives of 1,2,4-triazole. Also, calculated I H chemical shift values compared with the experimental ones. (C) 2009 Elsevier B.V. All rights reserved
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