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121.
Abdullah Aydın Mehmet Akkurt Leyla Uzun Leyla Yıldırım Tijen Önkol 《Journal of chemical crystallography》2010,40(10):816-820
Abstract
The title compound {6-[2-(2-chlorophenyl)-1,3-thiazol-4-yl]-2-oxo-1,3-benzothiazol-3(2H)-yl}acetic acid was prepared and characterized by elemental analyses, FT-IR, 1H NMR spectroscopy, X-ray diffraction. A quantum-chemical calculation was performed using the CNDO method. In the title compound, C18H11ClN2O3S2, the crystal structure is stabilized by intermolecular hydrogen bonds (C–H···O=C) to form centrosymmetric R22 R_{2}^{2} (16) dimers and the C–H···O, O–H···N, and C–H···N interactions generating the graph set motifs R22 R_{2}^{2} (9) and R22 R_{2}^{2} (22). 相似文献122.
The title molecules, N-(1,5-dimethyl-3-oxo-2-phenyl-1H-3-(2H)-pyrazolyl)4-nitrobenzamide (C18H16N4O4·H2O) (I) and 2,2-dimethyl-3-(4-nitrobenzoyl)-5-(phenylamino)-2,3-dihydro-1,3,4-thiyadiazole (C17H16N4O3S) (II), were prepared and characterised by 1H NMR, 13C NMR, infrared spectroscopy (IR) and structural X-ray diffraction (XRD) techniques. The molecular geometries, vibrational frequencies of the title compounds in the ground state have been calculated by using the density functional theory (DFT) method with 6-31G(d) basis set, and compared with the experimental data. The calculated results showed that the optimised geometries from the DFT method agree with the X-ray structures well for both compounds. Theoretical calculations of harmonic vibration frequencies are in good agreement with experimental results. To determine conformational flexibility, the molecular energy profiles of the title compounds were obtained. Besides, molecular electrostatic potential (MEP), frontier molecular orbitals (FMO) analysis and thermodynamic properties of the title compounds were investigated by theoretical calculations. 相似文献
123.
Ayd?n Aybar Altu? ?ftar 《Nonlinear Analysis: Hybrid Systems》2012,6(1):712-729
Supervisory controller design to enforce boundedness, reversibility, and liveness in timed-transition Petri nets with firing durations is considered. It is assumed that both controllable and uncontrollable transitions may be present and more than one transition may fire simultaneously. The approach of stretching is used to represent the state of the system. Algorithms are presented to design a supervisory controller using the forbidden states approach to enforce boundedness and reversibility simultaneously. The designed controller also guarantees T-liveness for the largest possible subset T of the set of transitions. In particular, boundedness, reversibility, and liveness are simultaneously enforced whenever it is possible. The designed controller is also the least restrictive controller which enforces boundedness and reversibility simultaneously. 相似文献
124.
Fatma Aydın Doğan Aykaç Hüseyin Ünver Nazan Ocak İskeleli 《Journal of chemical crystallography》2012,42(4):381-387
Abstract
A new 3,3′-dibenzoyl-1,1′-propan-1,3-diyl)bisthiourea was synthesized by using benzoylisothiocyanate with 1,3-diaminopropane in aprotic solvent. The structure was determinated by means of FT-IR, 1H-NMR, 13C-NMR and mass spectroscopic techniques. The crystal structure of 3,3′-dibenzoyl-1,1′-(propan-1,3-diyl)bisthiourea has also been examined by using X-ray crystallographic techniques and found to be crystallized in the monoclinic space group P2 1 /c with the unit cell parameters: a = 5.968(1) ?, b = 19.471(2) ?, c = 16.585(2) ?, β = 98.32(1)°, V = 1907.0(4) ?3, Dx = 1.395 g cm−3, and Z = 4 respectively. 相似文献125.
In this paper, we sketch some recent developments in the theory of Lyapunov-type inequalities and present some new results relating to a quasilinear system, special cases of which contain some well-known differential equations such as half-linear and linear equations. Our result generalize the Lyapunov-type inequality given in [18]. 相似文献
126.
127.
Mehmet Akköse Süleyman AdanurAlemdar Bayraktar A. Aydın Dumanoğlu 《Applied Mathematical Modelling》2008
Elasto-plastic earthquake response of arch dams including fluid–structure interaction by the Lagrangian approach is mainly investigated in this study. To this aim, three-dimensional eight-noded version of Lagrangian fluid finite element including the effects of compressible wave propagation and surface sloshing motion, and three-dimensional version of Drucker–Prager model based on associated flow rule assumption were programmed in FORTRAN language by authors and incorporated into the program NONSAP. Two new components added into the NONSAP were tested on a simple fluid tank and a simple fluid–structure system and obtained very reasonable results. 相似文献
128.
In this study, the effect of the viscous dissipation in steady, laminar mixed convection heat transfer from a heated/cooled vertical flat plate is investigated in both aiding and opposing buoyancy situations. The external flow field is assumed to be uniform. The governing systems of partial differential equations are solved numerically using the finite difference method. A parametric study is performed in order to illustrate the interactive influences of the governing parameters, mainly, the Richardson number, Ri (also known as the mixed convection parameter) and the Eckert number, Ec on the velocity and temperature profiles as well as the friction and heat transfer coefficients. Based on the facts the free stream is either in parallel or reverse to the gravity direction and the plate is heated or cooled, different flow situations are identified. The influence of the viscous dissipation on the heat transfer varied according to the situation. For some limiting cases, the obtained results are validated by comparing with those available from the existing literature. An expression correlating Nu in terms of Pr, Ri and Ec is developed. 相似文献
129.
Aktaş Aydın Erdemir Fatoş Barut Celepci Duygu Gök Yetkin Aygün Muhittin 《Transition Metal Chemistry》2019,44(3):229-236
Transition Metal Chemistry - A series of 2-hydroxyethyl-substituted N-heterocyclic carbene–(NHC)PdX2PPh3 complexes have been synthesized by substitution of the pyridine or 3-chloropyridine... 相似文献
130.
In this study, laminar boundary layer flow over a flat plate embedded in a fluid-saturated porous medium in the presence of
viscous dissipation, inertia effect and suction/injection is analyzed using the Keller box finite difference method. The flat
plate is assumed to be held at constant temperature. The non-Darcian effects of convection, boundary and inertia are considered.
Results for the local heat transfer parameter and the local skin friction parameter as well as the velocity and temperature
profiles are presented for various values of the governing parameters. The non-Darcian effects are shown to decrease the velocity
and to increase the temperature. It is also shown that the local heat transfer parameter and the local skin friction parameter
increase due to suction of fluid while injection reverses this trend. It is disclosed that the effect of the viscous dissipation
for negative values of Ec (T
w
< T
∞) is to enhance the heat transfer coefficient while the opposite is true for positive values of Ec (T
w
> T
∞). The results are compared with those available in the existing literature and an excellent agreement is obtained. 相似文献