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61.
62.
A dipyrromethane functionalized monomer, 5-(4-tert-butylphenyl)dipyrromethane (DP), was synthesized to examine the spectral differences of its copolymer and blend with 3,4-ethylenedioxythiophene. Electrochemical polymerization, copolymerization, and blending of DP were achieved in LiClO4/Acetonitrile. Spectral and electrochromic properties of products were investigated. Spectral properties of copolymer and blend revealed great differences from each other and also from their corresponding homopolymers. Effect of monomer feed ratio on the spectral properties of copolymer was also investigated. 相似文献
63.
Halil Kutuk Hasan Yakan 《Phosphorus, sulfur, and silicon and the related elements》2013,188(7):1460-1469
Abstract The acid-catalyzed hydrolysis of N-(4-substitutedarylthio)phthalimides was studied in aqueous solutions of sulfuric, perchloric, and hydrochloric acids at 40.0 ± 0.1 °C. Analysis of the data by the excess acidity method, activation parameters, and substituent effects indicates hydrolysis by an A-2 mechanism at low acidity. At higher acidities, a changeover to an A-1 mechanism is observed. GRAPHICAL ABSTRACT 相似文献
64.
Halil Güler Figen Kurtuluş İmdat Kadan Ayşe Morkan Sebahat Akin 《Phosphorus, sulfur, and silicon and the related elements》2013,188(6):1371-1379
In this study, the sulfidization of Na2CO3 was investigated by using a solid-gas reaction under a sulfidizing gas mixture, which consisted of COS, CS2, and S2 gases. Sodium sulfide pentahydrate, Na2S·5H2O, was prepared from sodium carbonate, Na2CO3, via a sulfidizing gas mixture by a solid-gas reaction under the cooling of a nitrogen atmosphere. The observed phase was found to be the pentahydrated form of sodium sulfide. This crystalline form was determined by X-ray powder diffraction (XRD) technique. Since sodium sulfide is strongly hygroscopic, the pentahydrated crystalline form was observed in XRD measurements for all repeated experiments. The crystal unit cell parameters of the synthesized product were in excellent agreement with values given in the JCPDS card number 18-1249. The sodium sulfide pentahydrate has an orthorhombic crystal structure with the unit cell parameters of a = 6.475, b = 12.55, C = 8.655 Å, space group, Cmcm and Z = 4. 相似文献
65.
M. Zafer Köylü Nadir Demirel F. Doganel Polat Ali Yιlmaz Halil Hoşgören Metin Balci 《Journal of inclusion phenomena and macrocyclic chemistry》2005,52(1-2):51-54
The complexation of the crown ethers with Na+ ion was studied. 1H-NMR chemical shifts are discussed in terms of structural modification as well as also binding studies with UV–vis spectra
were included.
This revised version was published online in July 2005 with a corrected issue number.
An erratum to this article is available at . 相似文献
66.
Mahmut Torul Halil Hogren Giray Topal Mürüvvet Yurdako 《Journal of heterocyclic chemistry》2005,42(6):1201-1205
A new selective molecular receptor, borocryptate, based on the combination of the 15 membered ring diazatrioxa core and two saligenin units as binding sites for boron has been described. The resulting peristatic chiral compound is stable in air and easily converted to polynuclear complex, Na‐borocryptate, without using an inert atmosphere. 相似文献
67.
5,10,15,20-tetrakis(phenoxy acetic acid) porphyrin (PAAP) was covalently linked to Merrifield chloromethylated resin. Characterization
of PAAP and the modified polymeric matrix were performed by 1H NMR, FTIR and elemental analysis. The sorbent was used for the separation and enrichment of the d-electron metals (Mn(II), Co(II), Ni(II), Cu(II) and Zn(II)) at pH 6–8 and of the f-electron metals U(VI) and Th(IV) at pH 4–5. The metals ions were preconcentrated with a concentration factor range of 115–215
and then determined by flame atomic absorption spectrometry or visible spectrophotometry using Arsenazo(III). The retained
metals were eluted with 2.0 mol L−1 HNO3 in the case of the d-electron metals and 0.1/0.25 mol L−1 HCl in the case of the f-electron metals. The procedure was validated by analyzing the NIST standard reference material 2709 (San Joaquin Soil).
Correspondence: Melek Merdivan, Chemistry Department, Faculty of Arts and Sciences, Dokuz Eylul University, 35160 Buca, Izmir,
Turkey 相似文献
68.
Novel different substitued polypyridine ligands 4-((4-(1H-imidazo[4,5-f][1,10]phenanthroline-2-yl)phenoxy)methyl)benzaldehyde (BA-PPY), (E)-N-(4-((4-(1H-imidazo[4,5-f][1,10]phenanthroline-2-yl)phenoxy)methyl)benzylidene)-pyrene-4-amine (PR-PPY), (E)-N-(4-((4-(1H-imidazo[4,5-f][1,10] phenanthroline-2-yl)phenoxy)methyl)benzylidene)-1,10-phenanthroline-5amine (FN-PPY), 2-(4-(bromomethyl)phenyl)-1H-imidazo[4,5-f][1,10] phenanthroline (BR-PPY), 2-(4-(azidomethyl)phenyl)-1H-imidazo[4,5-f][1,10]phenanthroline (N3-PPY) and triazole containing polypyridine ligand 3,4-bis[(4-(metoxy)-1,2,3-triazole)1-methylphenyl)-1H-imidazo[4,5-f][1,10]phenanthroline)] benzaldehyde (BA-DIPPY) and Ruthenium(II) complexes were synthesized and characterized. Their photopysical properties were investigated. The complexes RuP(PR-PPY), RuB(PR-PPY, RuP(FN-PPY) and RuB(FN-PPY) exhibited a broad absorption bands at 485, 475, 476, and 453 nm, respectively, assignable to the spin-allowed MLCT (dπ–π*) transition. The emission maxima of the pyrene-appended polypyridine ligand PR-PPY was observed at λems = 616 nm and the phenanthroline-appended polypyridine ligand FN-PPY was observed at λems = 668 nm. And the emission maxima of the complexes RuP(PR-PPY), RuB(PR-PPY), RuP(FN-PPY) and RuB(FN-PPY) were observed at λems = 646, 646, 685 and 685 nm, respectively. As seen in fluorescence spectra, the fluorescence intensities of the ligands are higher than their metal complexes. This is because of quenching effect of Ruthenium(II) metal on chromophore groups. 相似文献
69.
sa Sdr Yadigar Gülseven Sdr Sndor Gbi Halil Berber Rui Fausto 《Molecules (Basel, Switzerland)》2021,26(9)
A new Schiff base compound, 3-(5-bromo-2-hydroxybenzylideneamino)phenol (abbreviated as BHAP) was synthesized and characterized by 1H- and 13C- nuclear magnetic resonance and infrared spectroscopies. DFT/B3LYP/6-311++G(d,p) calculations were undertaken in order to explore the conformational space of both the E- and Z- geometrical isomers of the enol-imine and keto-amine tautomers of the compound. Optimized geometries and relative energies were obtained, and it was shown that the most stable species is the E-enol-imine form, which may exist in four low-energy intramolecularly hydrogen-bonded forms (I, II, V, and VI) that are almost isoenergetic. These conformers were concluded to exist in the gas phase equilibrium with nearly equal populations. On the other hand, the infrared spectra of the compound isolated in a cryogenic argon matrix (10 K) are compatible with the presence in the matrix of only two of these conformers (conformers II and V), while conformers I and VI convert to these ones by quantum mechanical tunneling through the barrier associated with the rotation of the OH phenolic group around the C–O bond. The matrix isolation infrared spectrum was then assigned and interpreted with help of the DFT(B3LYP)/6-311++G(d,p) calculated infrared spectra for conformers II and V. In addition, natural bond orbital (NBO) analysis was performed on the most stable conformer of the experimentally relevant isomeric form (E-enol-imino conformer V) to shed light on details of its electronic structure. This investigation stresses the fundamental structural relevance of the O–H···N intramolecular H-bond in o-hydroxyaryl Schiff base compounds. 相似文献
70.
A tensor method is used to formulate the on-axis scintillation index for an elliptical Gaussian beam (EGB; astigmatic Gaussian beam) propagating in a weak turbulent atmosphere. Variations of the on-axis scintillation of an EGB are studied. It is interesting to find that the scintillation index of an EGB can be smaller than that of a circular Gaussian beam in a weakly turbulent atmosphere under certain conditions and is closely related to the ratio of the beam waist size along the long axis to that along the short axis of the EGB, the wavelength, and the structure constant of the turbulent atmosphere. 相似文献