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81.
We introduce a class of differential equations on variable time scales with a transition condition between two consecutive parts of the scale. Conditions for existence and uniqueness of solutions are obtained. Periodicity, boundedness and stability of solutions are considered. The method of investigation is by means of two successive reductions: B-equivalence of the system [E. Akalín, M.U. Akhmet, The principles of B-smooth discontinuous flows, Computers and Mathematics with Applications 49 (2005) 981–995; M.U. Akhmet, Perturbations and Hopf bifurcation of the planar discontinuous dynamical system, Nonlinear Analysis 60 (2005) 163–178; M.U. Akhmet, N.A. Perestyuk, The comparison method for differential equations with impulse action, Differential Equations 26 (9) (1990) 1079–1086] on a variable time scale to a system on a time scale, a reduction to an impulsive differential equation [M.U. Akhmet, Perturbations and Hopf bifurcation of the planar discontinuous dynamical system, Nonlinear Analysis 60 (2005) 163–178; M.U. Akhmet, M. Turan, The differential equations on time scales through impulsive differential equations, Nonlinear Analysis 65 (2006) 2043–2060]. Appropriate examples are constructed to illustrate the theory. 相似文献
82.
Turan Kaya Yazıcılar Evrim Yılmaz Gürkan İbrahim Uçar Canan Kazak 《Transition Metal Chemistry》2009,34(6):669-676
Four novel transition metal benzenesulfonate (BS) complexes of imidazole (im) with a general formula [M(imH)3(H2O)3]·(BS)2 [M=Mn(II) (1), Ni(II) (2), Co(II) (3)] and [Cu(BS)(imH)3]·(BS) (4) have been synthesized and characterized by physicochemical and spectroscopic methods. The complexes 2 and 3 have also been characterized by single X-ray diffraction technique. The BS anion in complexes 1–3 acts as a counter anion, while in complex 4, it acts as both ligand and counter anion. The Ni and Co complexes are isomorphous, crystallizing in the monoclinic crystal
system with C2/c space group. Each metal(II) atom in 2 and 3 is octahedrally coordinated by three imidazole and three aqua ligands, adopting a mer-coordination mode with Ni(II) or Co(II) centers. In both 2 and 3, the H2C atom has bifurcated donor (O3 and O5) atoms, forming a bifurcated hydrogen bond. This hydrogen bond links the complex
cation and BS anion, forming one-dimensional hydrogen-bonded supramolecular chains. The complexes exhibit different decomposition
characteristics. Magnetic susceptibility measurement shows that complex 3 has orbital interactions. 相似文献
83.
84.
In this study, two novel Schiff base ligands (L1 and L2) derived from condensation of methyl 2-amino-6-methyl-4,5,6,7-tetrahydrothieno[2,3-c]pyridine-3-carboxylate and methyl 2-amino-6-phenyl-4,5,6,7-tetrahydrobenzo[b]thiophene-3-carboxylate, both starting matter with 5-bromo-salicylaldehyde, and their Zn(II) and Ni(II) metal complexes have been prepared using a molar ratio of ligand:metal as 1:1 except the Ru(II) complexes 1:0.5. The structures of the obtained ligands and their metal complexes were characterized by elemental analysis, FT-IR, 1H NMR, 13C NMR, UV–vis, thermal analysis methods, mass spectrometry, and magnetic susceptibility measurements. Antioxidant and antiradical activity of Schiff base ligands and their metal complexes were been evaluated in vitro tests. Antioxidant activities of metal complexes generally were more effectives than free Schiff bases. 1c and 2c were used as catalysts for the transfer hydrogenation (TH) of ketones. 1c, 2c complexes were found to be efficient catalyst for transfer hydrogenation reactions. 相似文献
85.
Özsin Gamzenur Dermenci Kamil Burak Turan Servet 《Journal of Thermal Analysis and Calorimetry》2021,146(3):1405-1420
Journal of Thermal Analysis and Calorimetry - Solid electrolytes for all-solid-state Li-ion batteries have attracted significant interest with their outstanding safety. But their poor ionic... 相似文献
86.
Nazl Turan Yücel Derya Osmaniye Ümmühan Kandemir Asaf Evrim Evren
zgür Devrim Can Ümide Demir
zkay 《Molecules (Basel, Switzerland)》2021,26(11)
In this study, we aimed to design and synthesize novel molecules carrying both the thiazole and piperazine rings in their structures and to investigate their antinociceptive activity. Targeted compounds were obtained by reacting thiosemicarbazide derivative and appropriate 2-bromoacetophenone in ethanol. The structures of the obtained compounds were determined using data from various spectroscopic methods (IR, 1H-NMR, 13C-NMR, and LCMSMS). Experimental data from in vivo tests showed that test compounds 3a–3c, 3f, and 3g (50 mg/kg) significantly prolonged reaction times of animals in tail-clip and hot-plate tests compared to the controls, indicating that these compounds possess centrally mediated antinociceptive activities. Furthermore, these compounds reduced the number of writhing behaviors in the acetic acid-induced writhing tests, showing that the compounds also possess peripheral antinociceptive activity. In the mechanistic studies, naloxone pre-treatments abolished the antinociceptive activities of compounds 3a–3c, 3f, and 3g, indicating that opioidergic mechanisms were involved in their antinociceptive effects. Molecular docking studies demonstrating significant interactions between the active compounds and µ- and δ-opioid receptor proteins supported the pharmacological findings. This study is the first showing that molecules designed to bear thiazole and piperazine moieties together on their structure exert centrally and peripherally mediated antinociceptive effects by activating the opioid system. 相似文献
87.
Veysel T. Yilmaz Turan K. Yazicilar Omer Andac Halil Kutuk Yunus Bekdemir William T. A. Harrison 《无机化学与普通化学杂志》2002,628(8):1908-1912
The reaction of sodium benzoxasulfamate (nbs) with cadmium(II) and mercury(II) sulfate in aqueous solution yield the novel complexes [Cd(nbs)2(H2O)4] (1) and [Hg(nbs)2(H2O)3] ( 2 ), respectively. The complexes were characterized by elemental analyses, IR spectroscopy and X‐ray crystallography. Complex 1 is monomeric and has an octahedral arrangement in which the N‐donor nbs ligands occupy the axial positions, while the water oxygen atoms form the equatorial plane. Complex 2 is polymeric and shows a pentagonal bipyramidal arrangement achieved by the bridging of the HgN2O3 units through the weak interaction of the O atoms of the nitro group. The nbs ligands also occupy the axial positions of the pentagonal bipyramid, whereas three water and two nitro oxygen atoms constitute the pentagonal plane. The crystal structure packing in both crystals is achieved by the intermolecular hydrogen bonds involving water hydrogen atoms, nitro and sulfonyl oxygen atoms. 相似文献
88.
89.
Recep Isci Dilara Gunturkun Ahsen Sare Yalin Turan Ozturk 《Journal of polymer science. Part A, Polymer chemistry》2021,59(1):117-123
Two novel copolymers of 4-thieno[3,2-b]thiophen-3-ylbenzonitrile (TT-CN), possessing electron withdrawing cyano moiety, with anthracene (P1) and biphenyl (P2) were prepared via Suzuki coupling. Optic, electronic, and thermal properties of the copolymers were investigated through UV–Vis spectroscopy, cyclic voltammetry, gel permeation chromatography, and thermal gravimetric analysis. The polymers with anthracene and biphenyl had electronic band gaps of 2.01 and 1.90 eV, respectively. Both polymers demonstrated excellent large Stokes shifts of 101 (anthracene) and 105 nm (biphenyl) as well as very good thermal properties. As they had good optical, electronic, and thermal properties, they are promising candidates for electronic applications. 相似文献
90.
Turan Neslihan Oruç Pınar Demirölmez Yeşim Seçkin Ayten Çağırtekin Ali Orkun Cavdar Sukru Koralay Haluk Tuğluoğlu Nihat 《Journal of Sol-Gel Science and Technology》2021,100(1):147-159
Journal of Sol-Gel Science and Technology - Zn0.95Co0.05O was synthesized by sol-gel method and then Zn0.95Co0.05O pellet was prepared to investigate its structural, morphological, electrical, and... 相似文献