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71.
Emine?Me?e Nurettin?Pirin??iog?lu Irfan?A??kg?z Figen?Binbay 《General Relativity and Gravitation》2009,41(1):87-92
In the post Newtonian limit, a non-relativistic Hamiltonian is derived for scalar fields with quartic self-interaction and
non-minimal coupling to the curvature scalar of the background spacetime. These effects are found to contribute to the non-relativistic
Hamiltonian by adding nonlinearities and by modifying the gravitational Darwin term. As we discuss briefly in the text, the
impact of these novel structures can be sizable in dense media like neutron star core, and can have observable signatures
in phase transitions, for example. 相似文献
72.
Bilge Taner Pervin Deveci Zafer Üstündaǧ Selda Keskin Emine Özcan Ali Osman Solak 《Surface and interface analysis : SIA》2012,44(2):185-191
3‐Aminophenylcalix[4]pyrrole (3APCP) was grafted to a glassy carbon (GC) surface during the electrochemical oxidation process in 0.1 M tetrabutylammoniumtetra‐fluoroborate (TBATFB) containing acetonitrile solution. The presence of a surface film was confirmed electrochemically by comparing voltammograms of dopamine and ferricyanide redox probes at the bare and modified electrodes. Reflection‐absorption infrared spectroscopy (RAIRS), XPS, atomic force microscopy (AFM), ellipsometry and the contact angle measurements were also employed to characterize 3APCP film on GC electrode. RAIRS analysis revealed that calix[4]pyrrole was bonded to the glassy carbon surface via the etheric linkage. The stability of the modified GC electrode was also studied. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
73.
Emine Salamci 《Tetrahedron》2010,66(23):4010-2897
A concise and efficient synthesis of cyclooctane-1,2,3,4-tetraoles, new polyhydroxylated eight-membered carbocycles, is described starting from cis,cis-1,3-cyclooctadiene. Cyclooctene endoperoxide obtained by photooxygenation of cis,cis-1,3-cyclooctadiene was the key compound in the synthesis. Reduction of the endoperoxide with zinc or thiourea followed by acetylation of the hydroxyl group and OsO4/NMO oxidation of the double bond gave (1R(S),2S(R),3R(S),4S(R))-cyclooctane-1,2,3,4-tetraol. Interestingly, epoxidation of cyclooctene-1,4-diol with m-CPBA also afforded trans-epoxy-diol 17. (1R(S),2R(S),3R(S),4S(R))-cyclooctane-1,2,3,4-tetraol was easily obtained by hydrolysis of epoxy-diol 17. 相似文献
74.
The host–guest complexation reactions between 5,11,17,23‐tetra‐tert‐butyl‐25,27‐diethoxycarbonylmethoxy‐26,28‐dimethoxy calix[4]arene (BDDC4) and alkali and alkaline‐earth metal ions were investigated by facilitated ion transfer processes across water/1,2‐dichloroethane microinterface by using steady‐state cyclic voltammetry and differential pulse voltammetry. The obtained facilitated transfers for Li+, Na+, K+, Rb+ and Ca2+ were evaluated under the different experimental conditions, at the excess concentrations of metal ions with respect to BDDC4 and vice versa. The association constants having 1 : 1 stoichiometry for Li+, Na+, K+ and Rb+ in 1,2‐DCE were determined. Also, we demonstrated that BDDC4 can play an important role for the development of highly selective chemical sensor for Ca2+ among alkaline‐metal ions in the concentration range of 0.1–1.0 mM in aqueous solution. 相似文献
75.
Gürbüz N Özcan EÖ Özdemir İ Çetinkaya B Şahin O Büyükgüngör O 《Dalton transactions (Cambridge, England : 2003)》2012,41(8):2330-2339
The reaction of [RuCl(2)(p-cymene](2) with Ag-N-heterocyclic carbene (NHC) complexes yields a series of [(p-cymene)Ru(NHC)] complexes (2a-f). All synthesised compounds were characterized by elemental analysis, NMR spectroscopy and the molecular structure of 2a was determined by X-ray crystallography. All complexes have been tested as catalysts for the transfer hydrogenation of aromatic ketones, showing excellent activity in this reaction. 相似文献
76.
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
77.
Palladium-catalyzed hydroarylations and additional domino reactions of aza-bicyclic and tricyclic norbornene derivatives were investigated and a series of new epibatidine analogues were synthesized. 相似文献
78.
Assessment of the orbital‐optimized coupled‐electron pair theory for thermochemistry and kinetics: Improving on CCSD and CEPA(1)
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An assessment of the orbital‐optimized coupled‐electron pair theory [or simply “optimized CEPA(0),” OCEPA(0)] [Bozkaya and Sherrill, J. Chem. Phys. 2013, 139, 054104] for thermochemistry and kinetics is presented. The OCEPA(0) method is applied to closed‐ and open‐shell reaction energies, barrier heights, and radical stabilization energies (RSEs). The performance of OCEPA(0) is compared with those of the MP2, CEPA(0), OCEPA(0), CEPA(1), coupled‐cluster singles and doubles (CCSD), and CCSD(T) methods [at complete basis set limits employing cc‐pVTZ and cc‐pVQZ basis sets]. For the most of the test sets, the OCEPA(0) method performs better than CEPA(0), CEPA(1), and CCSD, and provides accurate results. Especially, for open‐shell reaction energies and barrier heights, the OCEPA(0)–CEPA(1) and OCEPA(0)–CCSD differences become obvious. Similarly, for barrier heights and RSEs, the OCEPA(0) method improves on CEPA(0) by 1.6 and 2.3 kcal mol?1. Our results demonstrate that the CEPA(0) method dramatically fails when the reference wave function suffers from the spin‐contamination problem. Conversely, the OCEPA(0) method can annihilate spin‐contamination in the unrestricted‐Hartree–Fock initial guess orbitals and can yield stable solutions. For overall evaluation, we conclude that the OCEPA(0) method is quite helpful not only for problematic open‐shell systems and transition‐states but also for closed‐shell molecules. Hence, one may prefer OCEPA(0) over CEPA(0), CEPA(1), and CCSD as an method, where N is the number of basis functions, for thermochemistry and kinetics. As discussed previously, the cost of the OCEPA(0) method is as much as of CCSD and CEPA(1) for energy computations. However, for analytic gradient computations, the OCEPA(0) method is two times less expensive than CCSD and CEPA(1). Further, the stationary properties of the OCEPA(0) method making it promising for excited state properties via linear response theory. © 2014 Wiley Periodicals, Inc. 相似文献
79.
Photooxygenation of 1, 4-cyclohexadiene 3 followed by reduction with LiAlH4 or thiourea gave (25/1)-cyclohex-3-ene-triol 7a. trans-Hydroxylation of triol 7a with three different methods afforded both of proto-quercitol la and vibo-quercitol 2a. 相似文献
80.
Ayşegül Karaküçük-İyidoğan Zeliha Mercan Emine Elçin Oruç-Emre Demet Taşdemir Derya İşler İbrahim Halil Kılıç 《Phosphorus, sulfur, and silicon and the related elements》2013,188(5):661-673
Abstract The synthesis and characterization of 18 novel thiosemicarbazones have been investigated as part of a research program on development of compounds with antibacterial and antioxidant activities. Among the tested compounds, 2-(4-hydroxybenzylidene)-N-[4-(trifluoromethoxy)phenyl]hydrazine carbothioamide (3g) and 2-(thiophen-2-ylmethylidene)-N-[4-(morpholin-4-yl)phenyl]hydrazine carbothioamide (4b) showed excellent inhibition potency at low concentration (0.5 μg/mL) against Gram-positive pathogens (Enterococcus faecalis and Staphylococcus aureus). All tested compounds were also found to possess antioxidant activity against 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical and 2,2’-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical cation. [Supplementary materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements for the following free supplemental files: Additional text, tables, and figures.] 相似文献