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11.
A sensor for ethanol is described that is based on the fluorescent probe 5,10,15,20-tetraphenyl porphyrin (TPP). Response is based on the quenching of the fluorescence of TPP by ethanol as a result of electrostatic attraction. The sensor linearly responds to ethanol in the concentration range from 1 to 75 vol.% and was applied to the determination of ethanol in various kinds of wines and whisky. 相似文献
12.
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
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14.
Yaser Acikbas Selahattin Bozkurt Erkan Halay Rifat Capan Mehmet Levent Guloglu Abdulkadir Sirit Matem Erdogan 《Journal of inclusion phenomena and macrocyclic chemistry》2017,88(1-2):77-83
Microwave irradiation has been found to be a highly efficient method for etherification of p-tert-butylcalix[4]arene with alkyl bromides or ditosylate. The corresponding products were obtained as a pure form in modest yield within short reaction time when the reactions were performed under microwave irradiation. 相似文献
15.
A new method based on microcolumn packed with ionic liquid-modified silica combined with flame atomic absorption spectrometry has been developed for the determination of lead in environmental samples. Several factors influencing the preconcentration efficiency of lead and its subsequent determination, such as pH of the sample, flow rate, mass of ionic liquid, and interfering effect, have been investigated. Lead could be quantitatively retained by ionic liquid-modified silica in the pH range of 5-7, and then eluted completely with 3.0 mL 1.0 mol L−1 HCl. The detection limit of this method for lead was 0.7 μg L−1 with preconcentration factor of 185, and the relative standard deviation (RSD) was 4.2% at 0.1 μg mL−1 Pb(II). This method has been applied for the determination of trace amount of lead in NIST standard reference material 2709 (San Joaquin Soil) and river water samples with satisfactory results. 相似文献
16.
M. Ayd?nZ. Durmus H. KavasB. Esat H. SözeriA. Baykal F. Y?lmazM.S. Toprak 《Polyhedron》2011,30(6):1120-1126
Poly(3-thiophene acetic acid)/Fe3O4 nanocomposite is synthesized by the precipitation of Fe3O4 in the presence of poly(3-thiophene acetic acid) (P3TAA). Structural, surface, morphological, thermal properties and conductivity characterization/evaluation of the nanocomposite were performed by XRD, FT-IR, TEM, TGA, and conductivity measurements, respectively. The capping of P3TAA around Fe3O4 nanoparticles was confirmed by FT-IR spectroscopy, the interaction being via bridging oxygens of the carboxylate and the nanoparticle surface through bidentate binding. The crystallite and particle size were obtained as 9 ± 2 nm and 11 ± 1 nm from XRD line profile fitting and TEM image analysis, respectively, which reveal nearly single crystalline nature of Fe3O4 nanoparticles. Magnetization measurements reveal that P3TAA coated magnetite particles do not saturate at higher fields. There is no coercivity and remanence revealing superparamagnetic character. Magnetic particle size calculated from the theoretical fitting as 9.1 nm which coincides the values determined from TEM micrographs and XRD line profile fitting. The comparison to the TEM particle size reveals slightly modified magnetically dead nanoparticle surface. 相似文献
17.
R.H. Spear M.T. Esat M.P. Fewell D.C. Kean T.H. Zabel A.M. Baxter S. Hinds 《Nuclear Physics A》1980,345(1):252-262
The static quadrupole moments Q2+ and B(E2; 0+ → 2+) values of the 2+ first excited states of 200Hg and 202Hg have been determined using the reorientation effect in Coulomb excitation. An annular silicon surface-barrier detector was used to detect backscattered 4He, 12C and 16O projectiles. It is found that for 200Hg, Q2+ = +1.07 ± 0.19 e · b(+0.98 ± 0.19 e · b) for destructive (constructive) interference from the 2+′ state, and B(E2; 0+ → 2+) = 0.853 ± 0.007 e2 · b2. For 202Hg, we find Q2+ = +1.01 ± 0.13 e · b (+0.87 ± 0.13 e · b) and B(E2; 0+ → 2+) = 0.605 ± 0.005 e2 · b2. The Q2+ value obtained for 200Hg is in agreement with previous work, but that for 202Hg is not. The results obtained are compared with the predictions of various nuclear models, and the mass dependence of Q2+ in the region 182 ≦ A ≦ 206 is examined. 相似文献
18.
Durmuş Bozkurt 《Linear and Multilinear Algebra》2013,61(2-3):125-130
19.
Sultan Akhtar Şeyda Tuğba Günday B. Rabindran Jermy M.A. Almessiere Ayhan Bozkurt 《Journal of Saudi Chemical Society》2019,23(4):477-485
In this work, we report an efficient method to produce pure hollow silica spheres (HSS) using phenyltrimethoxysilane (PTMS) compound. The production of HSS was carried out via hydrolysis of PTMS in the aqueous media and followed by a condensation reaction to form silica spheres with phenyl groups. The product was then calcined to remove phenyl groups and obtain pure silica spheres with >95% fine structure. The chemical nature of pure silica was confirmed by Fourier transforms infrared spectroscopy. The calcined HSS were stable beyond the temperature of 900 °C as confirmed by thermal gravimetric analysis (TGA). The calcined spheres preserved their spherical appearance and hollow core as shown by SEM and TEM micrographs. Interestingly, the average size of the spheres was reduced significantly after calcination from 760 to 510 nm, confirming further the removal of phenyl groups. The calcined HSS offered much higher surface area (As) when analysed by BET; As for calcined product was ~406 and mere ~4.8 m2/g for uncalcined HSS. Finally, drug release study of cisplatin/HSS showed over 45% of steady cumulative release for 72 h. The prepared HSS can be dispersed in water opening the possibility of many novel bio/non-bio applications. 相似文献
20.
Bozkurt E Kartal I Karabulut B Uçar I 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2008,71(3):794-797
The electron paramagnetic resonance spectra of Cu(2+) impurities in [Co(nicotinamide)(2)(H(2)O)(4)](saccharinate)(2) single crystals have been studied at ambient temperature in three mutually perpendicular planes. The angular variation of the spectra shows that the Cu(2+) ion substitutes the Co(2+) site in the lattice. The EPR spectra of Cu(2+) ions are characteristic of tetragonally elongated octahedral site. The spin-Hamiltonien parameters were obtained from the single crystal EPR analysis. The ground-state wave function of Cu(2+) ion in the lattice has been constructed. 相似文献