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101.
In this paper we give the definition of the Fluctuationlessness concept and using this concept we make approximations to univariate
functions by using Taylor expansion with the explicit remainder term. Then integrating this approximate expression we obtain
a new quadrature-like numerical integration method. The results of numerical experiments are compared with the results obtained
from the corresponding Taylor series expansion without the remainder term and errors are analyzed. 相似文献
102.
The addition of acetylacetone to alkenes was performed using Mn(OAc)3·2H2O in the presence of HCl. The intermediate formed was trapped by chloride. Removal of one of the acetyl groups with ammonia under very mild conditions provided compounds derived from chloroacetonylation of the double bonds. 相似文献
103.
In this paper, we introduce the Euler sequence space e
r
(p) of nonabsolute type and prove that the spaces e
r
(p) and l(p) are linearly isomorphic. Besides this, we compute the α-, β- and γ-duals of the space e
r
(p). The results proved herein are analogous to those in [ALTAY, B.—BASŠAR, F.: On the paranormed Riesz sequence spaces of non-absolute type, Southeast Asian Bull. Math. 26 (2002), 701–715] for the Riesz sequence space r
q
(p). Finally, we define a modular on the Euler sequence space e
r
(p) and consider it equipped with the Luxemburg norm. We give some relationships between the modular and Luxemburg norm on this
space and show that the space e
r
(p) has property (H) but it is not rotund (R). 相似文献
104.
Metin?AslanEmail author Battal G.?Yalcin Mehmet?Ustundag Sadik?Bagci 《The European Physical Journal B - Condensed Matter and Complex Systems》2015,88(11):312
The structural and electronic properties of cubic B x Ga1?x As1?y Bi y alloys with bismuth (Bi) concentration of 0.0625, 0.125, 0.1875 and 0.25 are studied with various boron (B) compositions by means of density functional theory (DFT) within the Wu-Cohen (WC) exchange correlation potential based on generalized gradient approximation (GGA). For all studied alloy structures, we have implemented geometric optimization before the volume optimization calculations. The obtained equilibrium lattice constants and band gap of studied quaternary alloys are investigated for the first time in literature. While the lattice constant behavior changes linearly with boron concentration, increasing small amount of bismuth concentration alter the lattice constant nonlinearly. The present calculation shows that the band gap decreases with increasing bismuth concentration and direct band gap semiconductor alloy became an indirect band gap with increasing boron concentration. From the band offset calculation we have shown that increasing B and Bi concentration in host GaAs reduced the valance band offset in a heterostructure formed by GaAs and studied alloys. 相似文献
105.
Metin Gürses 《General Relativity and Gravitation》2010,42(6):1413-1426
We show that the Gödel type metrics in three dimensions with arbitrary two dimensional background space satisfy the Einstein-perfect fluid field equations. We also show that there exists only one first order partial differential equation satisfied by the components of fluid’s velocity vector field. We then show that the same metrics solve the field equations of the topologically massive gravity where the two dimensional background geometry is a space of constant negative Gaussian curvature. We discuss the possibility that the Gödel type metrics to solve the Ricci and Cotton flow equations. When the vector field u μ is a Killing vector field, we came to the conclusion that the stationary Gödel type metrics solve the field equations of the most possible gravitational field equations where the interaction lagrangian is an arbitrary function of the electromagnetic field and the curvature tensors. 相似文献
106.
Hasan Tanak Yavuz Köysal Yasemin Ünver Metin Yavuz Şamil Işık Kemal Sancak 《Structural chemistry》2009,20(3):409-416
The Imidazole compound, Ethyl N′-3-(1H-imidazol-1-yl) propylcarbamoyl benzohydrazonate monohydrate, has been synthesized and
characterized by IR, NMR, electronic spectroscopy, and X-ray single-crystal determination. Molecular geometry from X-ray experiment
of the title compound in the ground state has been compared using the density functional method (B3LYP) with 6-31G+(d) basis
set. To determine conformational flexibility, molecular energy profile of the title compound was obtained by DFT calculations
with respect to two selected degrees of torsional freedom, which were varied from −180° to +180° in steps of 10°. Besides,
molecular electrostatic potential (MEP), natural bond orbitals (NBO), frontier molecular orbitals (FMO), and thermodynamic
properties were performed at B3LYP/6-31G+(d) level of theory. 相似文献
107.
In this work, a new rational approximation scheme, based on the recently developed Transformational High Dimensional Model
Representation (THDMR) approximation method is developed. As an initial step to the construction of a rational approximation
for multivariate functions via THDMR, this paper focuses on the general theoretical background of the method and gives explicit
formulae for the computation of such approximants. The performance of the technique is shown by several examples both in univariate
and bivariate cases. 相似文献
108.
H. Ibrahim Ugras Ismet Basaran Turgut Kilic Umit Cakir 《Journal of heterocyclic chemistry》2006,43(6):1679-1684
109.
No fluctuation approximation in any desired precision for univariate function matrix representations
Metin Demiralp 《Journal of mathematical chemistry》2010,47(1):99-110
The operator involving problems are mostly handled by using the matrix representations of the operators over a finite set
of appropriately chosen basis functions in a Hilbert space as long as the related problem permits. The algebraic operator
which multiplies its operand by a function is the focus of this work. We deal with the univariate case for simplicity. We
show that a rapidly converging scheme can be constructed by defining an appropriate fluctuation operator which projects, in
fact, to the complement of the space spanned by appropriately chosen finite number of basis functions. What we obtain here
can be used in efficient numerical integration also. 相似文献
110.
Tümer Mehmet Köksal Hüseyin Serin Selahattin Dig¯rak Metin 《Transition Metal Chemistry》1999,24(1):13-17
Mixed-ligand complexes of copper(II) with 1,10-phenanthroline and various Schiff bases have been prepared and characterized by elemental analysis, electronic and i.r. spectra, magnetic moment and molar conductance data. The Schiff base behave as bidentate ligands, and the mixed-ligand copper(II) complexes of the ligands HL1, HL2 and HL4 are binuclear. The conductivity data for all the complexes are consistent with those expected for an electrolyte. Antimicrobial activities of some of the ligands and complexes have been tested against Bacillus megaterium and Candida tropicalis. 1H and 13C n.m.r. spectra have been recorded in order to solve the solution structure of the ligands. Thermal properties of all complexes have been studied by the d.t.a. and t.g.a. techniques. 相似文献