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111.
Nilay Akgnüllü Niyazi ahin Mehmet Sezer 《Numerical Methods for Partial Differential Equations》2011,27(6):1707-1721
In this study, a Hermite matrix method is presented to solve high‐order linear Fredholm integro‐differential equations with variable coefficients under the mixed conditions in terms of the Hermite polynomials. The proposed method converts the equation and its conditions to matrix equations, which correspond to a system of linear algebraic equations with unknown Hermite coefficients, by means of collocation points on a finite interval. Then, by solving the matrix equation, the Hermite coefficients and the polynomial approach are obtained. Also, examples that illustrate the pertinent features of the method are presented; the accuracy of the solutions and the error analysis are performed. © 2010 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 27: 1707–1721, 2011 相似文献
112.
Ataç A Yurdakul Ş Berber S 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2011,81(1):684-689
We report synthesis of six new bis-nicotinamide metal(II) dihalide complexes [M(nia)(2)Cl(2); M = Mn, Co; nia:nicotinamide, M(nia)(2)Br(2); M = Mn, Hg; M(nia)(2)I(2); M = Cd, Cu], and their characterization by combining infrared spectroscopy with density functional theory (DFT) calculations. Infrared spectra indicate that ring-nitrogen is the active donor cite, and the atomic structure of the complexes is determined to be polymeric octahedral or distorted polymeric octahedral. Spin polarized electronic ground state is obtained for Mn, Co, and Cu halide complexes. The colors of the complexes also support the conclusion of octahedral coordination around the metal atoms, in agreement with DFT results. 相似文献
113.
Carbon-supported PtRu nanoparticles (Ru/Pt: 0.25) were prepared by three different methods; simultaneous reduction of PtCl(4) and RuCl(3) (catalyst I) and changing the reduction order of PtCl(4) and RuCl(3) (catalysts II and III) to enhance the performance of the anodic catalysts for methanol and ethanol oxidation. Structure, microstructure and surface characterizations of all the catalysts were carried out by X-ray diffraction (XRD), transmission electron microscopy (TEM) coupled with energy dispersive X-ray spectroscopy (EDS) and X-ray photoelectron spectroscopy (XPS). The results of the XRD analysis showed that all catalysts had a face-centered cubic (fcc) structure with different and smaller lattice parameters than that of pure platinum, showing that the Ru incorporates into the Pt fcc structure by different ratios in all the catalysts. The typical particle sizes of all catalysts were in the range of 2-3 nm. The most active and stable catalyst for methanol and ethanol oxidation is catalyst III, in which a large amount (more than 90%) of PtRu alloy formation was observed. It has been found that this catalyst is about 8.0 and 33.4 times more active at ~0.60 V towards the methanol and ethanol oxidation reactions, respectively, compared to the commercial Pt catalyst. 相似文献
114.
Numerical Algorithms - We propose an algorithm to find a starting point for iterative methods. Numerical experiments show empirically that the algorithm provides starting points for different... 相似文献
115.
The differential cross sections for coherent scattering of 59.5 keV γ-rays by Mo and Sn were measured using a high-purity germanium detector. The results were compared with predictions of form factor theories and S-matrix calculations. 相似文献
116.
Sema Özturk Şamil Işik Erbil Aguar Selami Şalsmaz H. K. Fun Ahmet Erdönmez 《光谱学快报》2013,46(2):245-254
Abstract The crystal structure of the title compound, C41 H35 N7 O6 S3 was determined as monoclinic by single crystal X-Ray diffraction technique. The molecular structure was identified by IR, 1H-NMR, 13C-NMR and elemental analysis. The crystal parameters of this compound are as follows: monoclinic P 2 1/n, a = 12.694(2) Å, b = 26.204(2) Å, c = 13.005(2) Å, β = 102.95(2)°, V = 4216.02(1) Å.3, Z = 4, Dx = 1.289 g/cm3, F(000) = 1704, λ (MoKα) = 0.71070 Å, μ = 0.2 mm?1. The structure was solved by SHELXS-97 and refined by SHELXL-97. R = 0.06 for 3178 observed reflections with I > 2σ (I). 相似文献
117.
A rapid and specific proton magnetic resonance spectroscopic method was developed for determining acetazolamide in tablets. Maleic acid was used as the internal standard and DMSO-d6 served as the NMR solvent. the concentration of drug per unit dose was calculated from the integration values for the resonance signals of acetazolamide at 2.14 ppm and maleic acid at 6.20 ppm. the method using commercial products gave comparable results of those obtained by the method of USP XXIII. 相似文献
118.
N.
zkan A. St. J. Murphy R. N. Boyd A. L. Cole M. Famiano R. T. Güray M. Howard L.
ahin J. J. ZachR. deHaan J. Grres M. C. WiescherM. S. IslamT. Rauscher 《Nuclear Physics A》2002,710(3-4)
Total cross section measurements for the 102Pd(p, γ)103Ag and 116Sn(p, γ)117Sb reactions have been performed in the proton energy range 2.6 to 4.25 MeV, and for the 112Sn(α, γ)116Te reaction over the alpha beam energy range 7.0 to 10.5 MeV. An activation technique was used in which gamma rays from decays of the reaction products were detected off-line by two hyper-pure germanium detectors in a low background environment. Where possible, reaction rates are derived and the results compared to those of calculations generated by the NON-SMOKER and the MOST statistical model codes so as to judge their applicability for describing the cross sections needed for network calculations of nucleosynthesis in explosive astrophysical environments via the γ- and rp-processes. 相似文献
119.
120.
A. Z. S¸ahin 《Heat and Mass Transfer》1996,32(1-2):133-139
An analytical solution for the temperature rise in a non-insulated slab is obtained for the cases in which direct resistance heating or induction heating is applied. The solutions for both cases are carried out simultaneously for better comparison. The effects of applied current frequency and the Bi number on the temperature profile are shown. The advantages of direct resistance and induction heating for certain industrial applications are discussed. 相似文献