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51.
The title compound, C21H29NS2, has been synthesized and its crystal structure has been determined from single crystal X-ray diffraction data. Crystals are monoclinic, a = 11.4923(8), b = 13.1842(7), c = 14.6583(8) Å, β = 109.983(6)°, sp. gr. P21/c, Z = 4. Mesityl and thiazole groups are in cis positions with respect to the cyclobutane ring. The cyclobutane ring is puckered, with a dihedral angle of 26.6(2)° between the two three-atom planes. The crystal structure involves one weak intermolecular C–H···S hydrogen-bond. The molecular geometry was also optimized using density functional theory (DFT/B3LYP) method with the 6-311G(d, p) basis set in ground state. Geometric parameters (bond lengths, bond angles and torsion angles) and vibrational assignments have been calculated theoretically and compared with the experimental data. 相似文献
52.
Aytaç Gürhan Gökçe Hayati Türkmen Muhittin Aygün Bekir Çetinkaya Orhan Büyükgüngör 《Structural chemistry》2008,19(1):57-62
Trans-Bis[1,3-bis(2,4-dimethylphenylimidazolidin-2-ylidene)]dichloropalladium(II), 4, was prepared from 1,3-bis(2,4-dimetilphenyl)imidazoliniumchloride. The crystal and molecular structure of 4 have been determined by single crystal X-ray diffraction. The title compound, C38H44N4PdCl2, crystalizes in the monoclinic space group P 21/n with a = 13.8713(9) Å, b = 12.1365(6) Å, c = 21.5499(15) Å. The Pd atom has a slightly distorted square planar coordination geometry. The molecules of the title compound are linked by C–H···Cl weak hydrogen bonds into two-dimensional sheets parallel to the (001) plane. In addition, the title compound was characterized by elemental analyses and NMR spectroscopy. 相似文献
53.
M. G. Cabiddu S. Cabiddu E. Cadoni R. Cannas S. De Montis C. Fattuoni S. Melis 《Journal of organometallic chemistry》2001,620(1-2):263-275
The metallation reactions of (methylthio)anilines with organolithium reagents and with the butyllithium–potassium tert-butoxide superbasic mixture are here described. The results show that the para isomer when treated with butyllithium gave a mixture of products with no selectivity. Using tert-butyllithium or superbases we obtained the substitution of the thiomethyl hydrogen. Moreover, superbase allowed to prepare the disubstituted product with the new groups in the thiomethyl and in ortho to this group. On the other side, both ortho and meta isomers were lithiated at the thiomethyl carbon by butyllithium and the other reagents. Starting from the unalkylated amine we prepared through three successive one-pot monometallations N,N-disubstituted amines with equal or different groups and bearing an alkylthio chain as long as wanted. 相似文献
54.
Er Ozge Eksin Ece Soylu Hale Melis Göçmen Bayram Nalbantsoy Ayşe Yurt Fatma Erdem Arzum 《Applied biochemistry and biotechnology》2019,187(4):1539-1550
Applied Biochemistry and Biotechnology - Snake venoms are a natural biological source that has potential therapeutic value with various protein compounds. Disintegrins originally were discovered as... 相似文献
55.
Claudio?Melis Riccardo?Dettori Simon?Vandermeulen Luciano?ColomboEmail author 《The European Physical Journal B - Condensed Matter and Complex Systems》2014,87(4):96
We present a molecular dynamics method addressed to the calculation of the latticethermal conductivity during the transient regime of approach to equilibrium from aninitial condition of nonuniform temperature profile. We thoroughly assess the basics, therobustness, and the accuracy of the method, in particular by showing that its results arebasically independent of most of the arbitrary simulation parameters. In addition, themethod here presented is computationally light, thus paving the way for the investigationof large systems. This feature is fully exploited to investigate the thermal transportproperties of disordered and nanostructured silicon samples, providing a clear atomisticpicture on the ability of grain boundaries and lattice disorder to affect thermalconductivity by improved scattering of vibrational modes with long mean free path. 相似文献
56.
Melis Ulu Dog?ru Neriman Varl?kl? Derya Baykal Güliz K?y Dog?ukan Ta?er Halife ?ag?lar Emine Gündüz 《International Journal of Theoretical Physics》2012,51(5):1545-1554
In this paper, we devote to investigate the energy-momentum problem of higher dimensional black holes in the general theory
of relativity. The energy and momentum complex of M?ller has been used for the calculations. Also, total energy and total
momentum of some special cases for higher dimensional black holes such as Schwarzschild-like black holes, Reissner-Nordstr?m-like
charged black holes, AdS-like black holes, topological black holes, BTZ-like and charged BTZ-like black holes were obtained.
It is invented that the momentum of black holes vanishes everywhere while the energy of black holes are not equal to zero
in higher dimension. Also the results agree with Yang and Radinschi or Vagenas results in three and four dimensional black
holes, respectively (Jang and Radinschi in AIP Conf. Proc. 895, 325, 2007; Vagenas in Mod. Phys. Lett. A 21, 1947, 2006). 相似文献
57.
We investigate quantum entanglement of gravitational configurations in 3D AdS gravity using the AdS/CFT correspondence. We
derive explicit formulas for the holographic entanglement entropy (EE) of the BTZ black hole, conical singularities and regularized
AdS3. The leading term in the large temperature expansion of the holographic EE of the BTZ black hole reproduces exactly its Bekenstein-Hawking
entropy S
BH
, whereas the subleading term behaves as ln S
BH
. We also show that the leading term of the holographic EE for the BTZ black hole can be obtained from the large temperature
expansion of the partition function of a broad class of 2D CFTs on the torus. This result indicates that black hole EE is
not a fundamental feature of the underlying theory of quantum gravity but emerges when the semiclassical notion of spacetime
geometry is used to describe the black hole. 相似文献
58.
Sezgin Aygün 《International Journal of Theoretical Physics》2010,49(9):2288-2298
The aim of this study is to investigate the energy-momentum distributions of texture and monopole topological defects metrics
in general relativity (GR). For this aim Einstein, Bergmann-Thomson, Landau-Lifshitz (LL), M?ller and Papapetrou energy-momentum
densities have been used in general relativity theory. We obtained that (i) for the texture metric only Einstein and Bergmann-Thomson
energy densities give the same results but the others energy and momentum densities do not provide the same results in GR;
(ii) for the monopole metric, while Einstein, Bergmann-Thomson and Papapetrou energy and momentum densities are giving the
same energy-momentum results, M?ller and Landau-Lifshitz densities do not give the same energy results with the other definitions
in GR. 相似文献
59.
Melis Kesik Ozgecan Kocer Fulya Ekiz Kanik Naime Akbasoglu Unlu Eda Rende Evren Aslan‐Gurel Rene M. Rossi Yasemin Arslan Udum Levent Toppare 《Electroanalysis》2013,25(8):1995-2006
Surface functionalization plays a crucial role in the design of biosensors. For this purpose, a novel functional monomer, 6‐(4,7‐bis(2,3‐dihydrothieno[3,4‐b][1,4]dioxin‐5‐yl)‐2H‐benzo[d][1,2,3]triazol‐2‐yl)hexan‐1‐amine (BEDOA‐6), was designed and synthesized. Poly(BEDOA‐6) was utilized as an immobilization matrix for glucose oxidase biosensor construction. Moreover, polymethylmethacrylate (PMMA) layered silicate nanocomposites were prepared by in situ suspension polymerization. Conducting polymer surface was modified with PMMA/clay nanocomposite material and a glucose biosensor was developed. In addition, XPS and SEM were utilized to characterize the surface properties. The biosensor shows a wide linear range between 2.8 µM and 1.2 mM to glucose with a low detection limit of 1.99 µM. Finally, the biosensor was tested on serum samples containing actual human blood. The results were in well‐agreement with a reference method. 相似文献
60.
V. F. Shumsky I. Getmanchuk T. Ignatova Yu. Maslak P. Cassagnau G. Boiteux F. Melis 《Rheologica Acta》2010,49(8):827-836
The viscoelastic characteristics of the blends of poly(methyl methacrylate)/poly(styrene-co-acrylonitrile) (PMMA/SAN) were investigated at various temperatures below, near, and above the phase separation temperature.
The investigated polymer system is characterized by a lower critical solution temperature. Rheological behavior of the blends
in the region of a phase separation was compared with change of the light scattering intensity. The presence of nanofillers
in the blend results in that the phase separation occurs at a higher temperature. At the isothermal conditions, the phase
separation begins earlier and proceeds with a higher rate as compared with the same blend without filler. The results of the
study show the considerable change of the viscoelastic characteristics of PMMA/SAN when the polymer system passes from the
homogeneous state to the heterogeneous one. Such characteristics as the dependence of the storage modulus (G
′) on the loss modulus (G
″), the dependence of the loss viscosity (η
″) on the dynamic viscosity (η
′), the dependences of the complex viscosity (η*), and the free volume fraction (f) on the blend composition are the most sensitive to the phase separation. The phase separation affects the characteristics
G
′(ω), where ω is the frequency only in a low-frequency range. Temperatures of phase separation were estimated using dependence G
′(T) at ω, which is the constant in the range of low frequencies. 相似文献