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41.
Synthesis and proton conductivity studies of polystyrene‐based triazole functional polymer membranes
Şehmus Özden Sevim Ünügür Çelik Ayhan Bozkurt 《Journal of polymer science. Part A, Polymer chemistry》2010,48(22):4974-4980
In this study, poly(vinylbenzylchloride) (PVBC) was produced by free‐radical polymerization of 4‐vinylbenzylchloride, and then it was functionalized with 3‐amino‐1,2,4‐triazole (ATri) and 1H‐1,2,4‐triazole (Tri). The composition of the polymers was verified by elemental analysis, and the structure was characterized by Fourier transform infrared and 13C‐nuclear magnetic resonance spectra. PVBC was modified by ATri with 68% and Tri with 50% yield. The polymers were doped with trifluoromethanesulfonic acid (TA) at various molar ratios, X = 0.5, 1, 2, and 3 with respect to aminotriazole and triazole units. Proton transfer from TA to the triazole rings was proved with Fourier transform infrared spectroscopy. Thermogravimetric analysis showed that the samples are thermally stable up to approximately 200 °C. Differential scanning calorimetry results illustrated the homogeneity of the materials. Under anhydrous conditions, PVBCATri3TA and PVBCTri3TA showed highest proton conductivity of 0.086 and 0.042 S/cm, respectively. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010 相似文献
42.
Esin Burunkaya Nadir Kiraz Ömer Kesmez Meltem Asilturk H. Erdem Çamurlu Ertuğrul Arpaç 《Journal of Sol-Gel Science and Technology》2010,56(2):99-106
In this study, new fluorinated silane system was prepared by adding hydroxyl terminated Fluorolink D10H oligomer to 3-isocyanatopropyltrietoxysilane. The obtained silane system was independently composed with 3-Glycidyloxypropyltrimethoxysilane
and 3-Glycidyloxy-propyltriethoxysilane. Then the prepared two different coating solutions were applied to glass surface by
spin-coating method. The chemical bonding between groups in system was investigated by FTIR analysis. The elemental composition
of coatings was determined by using EDX analysis. Their structure and surface properties were analyzed by scanning electron
microscopy, atomic force microscopy, contact angle measurement and UV–vis spectrophotometer. The amounts of fluorine on the
coatings prepared with IPTES-D10H-GLYEO and IPTES-D10H-GLYMO were 33 and 34 %wt, respectively. Transparent coatings with smooth
surface and uniform thickness were obtained. The coatings had nanoscale roughness. The contact angles of coatings for water
were range from 103° to 110°, and for n-hexadecane were range from 59° to 62°. 相似文献
43.
Savaş Sönmezoğlu Sevilay Şenkul Recep Taş Güven Çankaya Muzaffer Can 《Solid State Sciences》2010,12(5):706-711
We have formed conjugated polymeric aniline–thiophene organic material on p-Si substrate by adding polyaniline–poly-3-methyl thiophene blend solution in acetonitrile on top of a p-Si substrate and then evaporating the solvent. It has been seen that the forward bias current–voltage (I–V) characteristics of polyaniline–poly-3-methyl thiophene blend/p-Si/Al with a barrier height value of 0.60 eV and an ideality factor value of 3.37 showed rectifying behaviour at room temperature. The polyaniline–poly-3-methyl thiophene blend/p-Si/Al Schottky barrier diode showed non-ideal I–V behaviour with the value of ideality factor greater than unity that could be ascribed to the interfacial layer, interface states and series resistance. Furthermore, Cheung's functions and modified Norde's function were used to extract the diode parameters including ideality factor, barrier height and series resistance. It has been seen that there is a good agreement between the barrier height values from all methods. However, the values of series resistance obtained from Cheung's functions is higher than the values obtained from Norde's functions. The energy distribution of interface states density, determined from forward bias current–voltage (I–V) characteristic technique at room temperature, increases exponentially with bias from 2.81 × 1016 cm?2 eV?1 in (0.73–Ev) eV to 1.14 × 1017 cm?2 eV?1 in (0.48–Ev) eV. 相似文献
44.
45.
Piano‐stool ([(p‐cymene)Ru(thz)Cl], 2 ) and six‐coordinated ([Ru(thz)2(PPh3)2], 3 ) ruthenium complexes derived from 2‐phenylthiazoline‐4‐carboxylic acid (Hthz, 1 ) were synthesized for the first time, and fully characterized using conventional methods. Also, the molecular structure of complex 3 was determined using X‐ray analysis. These complexes were evaluated as catalysts for transfer hydrogenation of carbonyl compounds in the presence of isopropyl alcohol and KOtBu. Complex 2 was found to be more active than 3 in transfer hydrogenation. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
46.
Naki Çolak Yılmaz Yıldırır Mustafa Kavutcu Nilhan Nurlu 《Monatshefte für Chemie / Chemical Monthly》2007,138(12):1283-1287
Summary. Methotrexate (MTX) is a folate antagonist used in treatment of several chronic inflammatory and neoplastic conditions. In this study, new MTX-like compounds that may-be potential anticancer agents were synthesized and their structures were determined by IR, UV, GC-MS,
1H NMR, and 13C NMR spectra. Also, in this study, a series structurally related to MTX or folate analogous compounds were evaluated whether they have inhibitory properties on the dihydrofolate reductase activity
(DHFR). 相似文献
47.
Erem Bilensoy Yasemin Çırpanlı Murat Şen A. Lale Doğan Sema Çalış 《Journal of inclusion phenomena and macrocyclic chemistry》2007,57(1-4):363-370
Human Papilloma Virus (HPV) infections are the major cause of cervical cancers. To achieve a better therapeutic efficacy and patient compliance in the treatment for HPV-induced cervical cancers, anticancer agent 5-fluorouracil has been formulated in a vaginal gel using the thermosensitive polymer Pluronic® F127 together with alternative mucoadhesive polymers e.g., hyaluronic acid, Carbopol 934 and hydroxypropylmethylcellulose. To increase its aqueous solubility and to achieve the complete release of 5-FU from the gel, the drug was incorporated as its inclusion complex with 1:1 molar ratio with either β-cyclodextrin or hydroxypropyl-β-cyclodextrin. Following the characterization of drug:CD complexes, thermosensitive gel formulations containing different mucoadhesive polymers and the drug in free or complexed form were characterized in vitro by determining the gelation temperature and the rheological behavior of different formulations along with the in vitro release profiles of these formulations in pH 5.5 citrate buffer. It was observed that complexation with cyclodextrin accelerated the release of 5-FU with the exception of formulation containing Carbopol 934 as mucoadhesive polymer. As far as rheological properties are concerned, favorable thermosensitive in situ gelling properties were obtained with formulations containing HPMC as mucoadhesive polymer. Complete release of 5-FU from gels were obtained with both complexes of β-CD and HP-β-CD and cytotoxicity studies against HeLa human cervical carcinoma cells demonstrated that 1% 5-FU:CD complexes were equally effective as 1% free 5-FU indicating better therapeutic efficacy with lower dose. 相似文献
48.
Rotation matrices were expressed in terms of Gaunt coefficients and complex spherical harmonics. The rotation matrices were calculated using two different ways. In the first, Gaunt coefficients and normalized complex spherical harmonics were directly calculated using binomial coefficients; in the second, Gaunt coefficients and complex spherical harmonics were recursively calculated. The methods were compared with respect to accuracy and computation time (CPU) for low and very high quantum numbers. 相似文献
49.
A CZE method was developed and validated for the analysis of Olmesartan medoxomil (OLMD) in tablets. The influences of pH, buffer concentration, applied voltage and capillary temperature on the migration time of OLMD were investigated. About 50 mM pH 6.5 phosphate buffer were used as background electrolyte. The optimum instrument parameters were found to be 30 °C temperature with 30 kV applied voltage and diode array detection was carried out at 210 nm. OLMD was hydrodynamically injected (P inj = 50 mbar, t inj = 3 s) and an internal standard, diflunisal (IS), was used to improve the precision and repeatability. Under these conditions, the migration time of OLMD was 2.32 min and the total analysis time was shorter than 5 min. Linearity range for the developed method was found to be 2.0–50.0 μg mL?1 and the limit of detection was 0.5 μg mL?1. The developed method was applied for the analysis of OLMD in pharmaceutical tablet formulations. 相似文献
50.