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101.
Asuman Celik Kucuk Faruk Yilmaz Hatice Can Hakan Durmaz Arif Kosemen Ali Ekrem Muftuoglu 《Journal of polymer science. Part A, Polymer chemistry》2011,49(19):4180-4192
Synthesis of a novel macroinimer comprising poly(ε‐caprolactone) (PCL) and thiophene (Th) and its use in electrochromic device (ECD) application have been reported. First, a novel Th monomer ( 5 ) with miktofuntional initiator groups (primary hydroxyl and tertiary bromide at the third position of the thiophene ring) was synthesized in a four‐step reaction sequence. Density functional theory‐predicted bond lengths, angles, and vibrations of 5 were in good agreement with available experimental vibrational spectra. Subsequently, ring‐opening polymerization of ε‐caprolactone (ε‐CL) was carried out in bulk using 5 as the initiator and tin(II) 2‐ethylhexanoate (Sn(Oct)2) as the catalyst at 115 °C, which led to α‐thiophene end‐capped PCL macroinimer (PCL‐Th). Furthermore, PCL‐Th macroinimer was used in electrochemical copolymerization with pyrrole (Py) and Th. PCL‐Th/PTh copolymer film synthesized on indium tin oxide‐coated glass slide showed electrochromic behavior. Optical analyses of the PCL‐Th/PTh copolymer film indicated that the copolymer film was suitable to be used as an anodically coloring material for ECD applications. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011 相似文献
102.
Hakan Yakut Emre Tabar A. Ali Kuliev Ekber Guliyev 《Central European Journal of Physics》2014,12(12):843-850
In this paper the Quasiparticle-Phonon Nuclear Model (QPNM), based on QRPA (Quasiparticle Random Phase Approximation) phonons, has been utilized to investigate spin polarization effects on the groundstate magnetic properties such as intrinsic magnetic moment (g K ) and effective spin gyromagnetic factor (g s eff. ) of odd-mass deformed 165–179Hf isotopes with K > 1/2. Investigations of the spin polarization effects of the even core on the magnetic moments show that the spin gyromagnetic factors (g s ) of the nucleons in the nucleus differ noticeably from the corresponding values for free nucleons and that the spin-spin interactions play an important role in the re-normalization of g s factors of the odd-mass 165–179Hf isotopes. In addition, some theoretical predictions are presented for the magnetic moments of 165Hf, 167Hf, and 169Hf, whose ground state magnetic moments haven’t been experimentally determined yet. 相似文献
103.
104.
Demet Sezgin Mansuroğlu Hakan Arslan Don VanDerveer Gün Binzet 《Phosphorus, sulfur, and silicon and the related elements》2013,188(12):3221-3230
A series of new N-(2,2-diphenylacetyl)-N ′-substituted thiourea derivatives (1–9) have been prepared and characterized by elemental analyses, IR and 1H NMR spectroscopy. N-(2,2-diphenylacetyl)-N ′-(4-chlorophenyl)-thiourea was also characterized by a single crystal X-ray diffraction study. The compound crystallizes in the monoclinic space group P21/c with Z = 4 and a = 9.6551(19) Å, b = 20.060(4) Å, c = 9.894(2) Å, β = 104.29(3)°. The molecular conformation of the compound is stabilized by an intramolecular (N1-H1···O1) hydrogen bond that forms a pseudo-six-membered ring. 相似文献
105.
Hakan Çiftçi Hasan Nur Testereci Zeki Öktem 《Russian Journal of Electrochemistry》2013,49(12):1160-1164
Conducting poly(2-aminothiazole) (PAT) films were electrodeposited on a platinum disc electrode surface by constant potential electrolysis of 2-aminothiazole (AT) for the stripping voltammetric determination of Ag(I). Ag(I) was preconcentrated on the polymer matrix by dipping the modified Pt electrode (PAT-Pt electrode) into Ag(I)(aq) solution. Effects of the film thickness, reduction potential, pH, preconcentration time, Ag(I) concentration and the interference of some other metal ions on the oxidation peak current of silver were studied. Cu(II) interference observed to be significant for the stripping voltammetric determination of Ag(I). The detection limit was calculated on the basis of signal to noise ratio of 3 as 2 × 10?7 mol L?1. 相似文献
106.
In this study, we synthesized a new series of substituted aliphatic 1,3,4-thiadiazol-2(3H)-one derivatives (6-24) in yields ranging from 42 to 70% with an interesting mechanism that involves internal nucleophilic substitution followed by an SN2-type nucleophilic substitution. First, 1-(4-chlorophenyl)-2-((5-methyl-1,3,4-thiadiazol-2-yl)thio)ethanone (3) was synthesized from the reaction of 5-methyl-1,3,4-thiadiazole-2-thiol (1) with 2-bromo-1-(4-chlorophenyl)ethanone (2) in the presence of potassium hydroxide. Then, 1-(4-chlorophenyl)-2-((5-methyl-1,3,4-thiadiazol-2-yl)thio)ethanol (4) was synthesized by a reduction reaction of this compound using NaBH4. Finally, 5-methyl-3-alkyl-1,3,4-thiadiazol-2(3H)-one derivatives (6-24), which are the target compounds, were synthesized from the reaction of this compound (4), which is a secondary alcohol with various alkyl halides (5a-n) in the presence of sodium hydride (NaH). This study presents an interesting reaction mechanism related to the synthesis of aliphatic 1,3,4-thiadiazol-2(3H)-one derivatives that is not recorded in the literature. 相似文献
107.
108.
Fatih Do■an Hakan Akat Ismet Kaya 《高分子科学》2008,(1):47-53
A new polymer,poly(imino isophthaloyl imino(2,4,8,10-tetraoksoaspiro[5,5]undekan-3,9-dipropylene)) [poly(IPIT)]was synthesized by an interfacial polycondensation reaction.The characterization of poly(IPIT)was conducted by using FT-IR,~(13)C-NMR,TG and DTA techniques.The kinetics of the thermal degradation of poly(IPIT)was investigated by thermogravimetric analysis at different heating rates.TG curves showed that the thermal decomposition of poly(IPIT) occurred in three stages.The apparent activation ener... 相似文献
109.
The decomposition of HOONO in water gives nitrate and a reactive oxidant whose identity has been debated. This oxidant has been argued to be a hydroxyl radical, but reported yields of hydroxyl-radical-trapped products range from only 0% to 40% in different experiments. Other oxidants, including the metastable HOONO*, have been proposed as intermediates. CPMD metadynamics simulations reported here show the mechanism of HOONO decomposition in water and the nature of the caged radical pair. 相似文献
110.
Lu G Usta H Risko C Wang L Facchetti A Ratner MA Marks TJ 《Journal of the American Chemical Society》2008,130(24):7670-7685
Realizing p-channel semiconducting polymers with good hole mobility, solution processibility, and air stability is an important step forward in the chemical manipulation of charge transport in polymeric solids and in the development of low-cost printed electronics. We report here the synthesis and full characterization of the dithienosilole- and dibenzosilole-based homopolymers, poly(4,4-di-n-hexyldithienosilole) (TS6) and poly(9,9-di-n-octyldibenzosilole) (BS8), and their mono- and bithiophene copolymers, poly(4,4-di-n-hexyldithienosilole-alt-(bi)thiophene) (TS6T1, TS6T2) and poly(9,9-di-n-octyldibenzosilole-alt-(bi)thiophene) (BS8T1, BS8T2), and examine in detail the consequences of introducing dithienosilole and dibenzosilole cores into a thiophene polymer backbone. We demonstrate air-stable thin-film transistors (TFTs) fabricated under ambient conditions having hole mobilities as large as 0.08 cm(2)/V x s, low turn-on voltages, and current on/off ratios > 10(6). Additionally, unencapsulated TFTs fabricated under ambient conditions are air-stable, an important advance over regioregular poly(3-hexylthiophene) (P3HT)-based devices. Density functional theory calculations provide detailed insight into the polymer physicochemical and charge transport characteristics. A direct correlation between the hole injection barrier and both TFT turn-on voltage and TFT polymer hole mobility is identified and discussed, in combination with thin-film morphological characteristics, to explain the observed OTFT performance trends. 相似文献