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21.
Nuri Ünal 《Foundations of Physics》1997,27(5):747-758
Barut's classicalzitterbewegung model includes the internal dynamical variables and the quantization of this system gives a general transition amplitude
between the different space-time points and internal coordinates and momentum. It includes the transition amplitude between
the half integer and integer spin eigenvalues. Spin eigenfunctions lead to all sets of relativistic wave equations, as well
as the Dirac equation. 相似文献
22.
H. Ünver M. Kabak D. Mehmet Zengin T. Nuri Durlu 《Journal of chemical crystallography》2001,31(4):203-209
1-[N-(4-chlorophenyl)]aminomethylidene-2(1H)naphthalenone (C17H12NOCl) (1) was synthesized and the crystal structure was determined. Compound 1 crystallizes in the monoclinic space group P21/n with a = 4.761(3) Å, b = 20.347(1) Å, c = 13.773(2) Å, = 92.89(3)°, V = 1332.4(3) Å3, Z = 4, D
c = 1.404 g cm–3, (Mo K) = 0.28 mm–1, and R = 0.036 for 2680 reflections [I > 2(I)]. Molecule 1 is not planar, and the dihedral angle between the naphthaldeyde plane A [C1–C11, 01] and the 4-chloroaniline plane B [C12–C17, C11, N1] is 20.1(3)°. An intramolecular hydrogen bond occurs between the hydroxyl oxygen and imine nitrogen atoms [2.528(3) Å]. IR, 1H NMR, and UV measurements and AM1 semiempirical quantum mechanical calculations support the keto form found in the X-ray structure. 相似文献
23.
We study gravity driven films of a Newtonian fluid flowing down sinusoidal bottom profiles. We give experimental evidence of vortices in the film flow under creeping flow conditions down to Reynolds numbers of the order of 10–5. The vortices are created in the valleys of the undulated bottom profile. They are visualized employing a particle image velocimeter with fluorescent tracers. It turns out that the vortices are generated beyond a critical film thickness. 相似文献
24.
5,6‐bis(4‐methylphenyl)‐2,3‐dihydro‐1,2,3,4‐tetrazine 2 was synthesized by the dimerization of ethyl p‐methylbenzoateformylhydrazone 1 in hydrazinehydrate solution. 2,3‐bis(4‐methylphenyl)‐6,7,14,15‐tetrahydro[1,2,3,4]tetrazino [2,3d][1,8, 4,5]benzodithia‐diazecine‐10,11‐dicarbonitrile 4 was sythesized by cyclization reaction of tetrazine monomer 2 onto 1,2‐bis‐(2‐iodoethylmercapto)‐4,5‐dicyanobenzene 3 . Co(II) and Cu(II) phthalocyanine complexes were prepared by reaction of the dinitrile compound ( 4 ) with the chlorides of Co(II), Cu(II), and DMAE at 175°C, 350 W in a microwave oven for 10 min. Zn(II)‐phthalocyanine complex was prepared by reaction of the dinitrile compound 4 with the acetate of Zn(II) and DMAE at 175°C, 350 W in a microwave oven for 10 min. The new compounds were characterized by a combination of IR, 1H‐NMR, 13C NMR, UV‐vis, elemental analysis, and MS spectral data. © 2010 Wiley Periodicals, Inc. Heteroatom Chem 21:456–461, 2010; View this article online at wileyonlinelibrary.com . DOI 10.1002/hc.20623 相似文献
25.
We extended the Barut’s classical model of zitterbewegung from 3+1 dimensional spacetime into 2+1 and 1+1 dimensional spacetimes and discussed the symmetry and integrability properties of the model in 2+1, 1+1 and 3+1 dimensions. In these cases, the free particle current or the velocity of the particle can be decomposed as a constant convection current and polarization currents. 相似文献
26.
Mehmet Kabak Yalin Elerman Canan Ünaleroglu Yüksel Mert T. Nuri Durlu 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(2):e66-e67
The structure of the title compound, C6H18N22+.2Cl?, has been determined and has a centre of symmetry. The molecule has strong intermolecular hydrogen bonding between each Cl? and an N—H bond [Cl?N = 3.012 (3) Å]. 相似文献
27.
M. Yıldız H. Ünver D. Erdener N. Ocak A. Erdönmez T. Nuri Durlu 《Crystal Research and Technology》2006,41(6):600-606
The title compound has been synthesised by the reaction of 2-hydroxy-1-naphthaldehyde with 2,5-dichloroaniline. The compound was characterized by elemental analysis, IR and UV-Visible techniques. The UV-Visible spectra of the Schiff base with OH group in ortho position to the imino group was studied in polar and nonpolar solvents in acidic and basic media. The structure of compound has been examined cyrstallographically. It crystallizes in the orthorhombic space group P212121 with a = 6.059(1), b = 12.105(2) c = 20.006(2) Å, V = 1467.4(3) Å3, Dx = 1.431 g.cm-3 and Z = 4. The crystal structure was solved by direct methods and refined by full-matrix least squares. Molecule of the title compound N-[2-hydroxy-1-naphthylidene]2,5-dichloroaniline is nearly planar. The molecule contains a strong intramolecular N…H-O hydrogen bond between the imine and hydroxyl group [O1 and N1 = 2.540(4) Å]. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
28.
Christian Heining Andreas Wierschem Vasilis Bontozoglou Nuri Aksel Hannes Uecker 《PAMM》2007,7(1):3020001-3020002
We study viscous gravity-driven films flowing over periodically undulated substrates. Linear analysis describes resonance in steady flow along small bottom corrugations for films of arbitrary thickness. Depending on the dimensionless film thickness we find different regimes for the resonance, which is associated with the interaction of the undulated film with capillarygravity waves traveling against the flow. Nonlinear resonance produces higher harmonics and bistable resonance. The higher harmonics are due to higher harmonics resonance and due to the nonlinear coupling to lower harmonics. For the bistable resonance we derive a minimum model showing that the bistability corresponds essentially to that of the driven Duffing oscillator. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
29.
We study gravity-driven viscous thin films flowing down an undulated plane. Applying the integral boundary-layer method we derive a set of two coupled PDEs for the film thickness and the flow rate. The steady state solution shows linear and nonlinear resonance. Based on this analytical solution we carry out a stability analysis with respect to surface waves and study wave generation and annihilation for time dependent flow. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
30.
Herein, we submitted to the original synthesis, characterization, energy transfer mechanism of the Bodipy-bearing pillar[5]arene Bodipy and its reactants by employing of infrared, 1H, 11B, 13C, 19F-NMRs, UV–vis, fluorescence spectroscopy, melting point apparatus, CHN elemental analysis and mass spectroscopy. Preliminary UV–vis, fluorescence and excitation measurements were carried out in CH2Cl2 and the results revealed an effective fluorescence resonance energy transfer (FRET) system based on the interaction of pillar[5]arene and Bodipy derivative. εmax of target molecule reached to a maximum value and it was found as 955 000?M?1?cm?1. This fluorescent macromolecule worked well for mimicking a light harvesting system with an energy transfer efficiency up to 92%. 相似文献