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A method for the extraction and selective determination of cations is proposed using electro-synthesized overoxidized sulfonated polypyrrole film. The polymer film is used for the selective extraction of trace levels of nickel and cadmium ions by solid-phase microextraction (SPME). The cation uptake and release properties of the overoxidized sulfonated polypyrrole film electrode were examined under both open circuit and controlled potential conditions for prospective applications in electrochemically controlled solid-phase microextraction. Increased extraction efficiency and selectivity toward cations were achieved in high saline content of water. Simple preparation of film coatings on a platinum wire was possible using a constant potential method. Applied positive and negative potentials facilitated the extraction and desorption of cations, respectively. Nickel and cadmium ions were desorbed into sample aliquot and determined by electrothermal atomic absorption spectrometry (ETAAS). The cation uptake and release mechanism is affected both by the cation exchange at the negative sulfonate and carboxylate moiety on the film and the altered solution pH occurring at the counter electrode caused by the applied potential. The method was validated using a standard reference material and tested for the determination of cadmium ion in commercial table salt samples. 相似文献
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Elif Gungor Mustafa Burak Coban Hulya Kara Yasemin Acar 《Journal of Cluster Science》2018,29(6):967-974
A new cubane-based cobalt(II) cluster, [Co4L4] (1), where H2L?=?2-((E)-(2-hydroxyethylimino) methyl)-4-chlorophenol has been prepared using a solvothermal process and characterized by structural, optical and magnetism. The crystal structure of 1 consists of a tetranuclear Co4O4 core in an open-cubane framework. Each cobalt(II) ion is penta-coordinated in a distorted square pyramidal geometry (τCo1=Co1i?=?0.030, τCo2=Co2i?=?0.023). Furthermore, the photoluminescence analysis indicates that 1 has a strong blue emission which should be attributed to coordination of the metal to the ligand. The temperature dependence of the magnetic susceptibilities of 1 shows antiferromagnetic coupling (J?=???26.61?±?0.01) between cobalt(II) ions. 相似文献
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Yasemin Çağlar Zekeriya Biyiklioglu 《Journal of inclusion phenomena and macrocyclic chemistry》2018,90(3-4):331-339
This study reports the synthesis of water soluble iron(II) phthalocyanine and a facile method for spectrophotometric determination of Hg(II) in environmental water samples by ionic liquid based dispersive liquid–liquid microextraction (IL-DLLME). In the method, 1-heptyl-3-methylimidazolium hexafluorophosphate (250 µL) as extraction solvent, acetonitrile (750 µL) as dispersive solvent and Triton X-100 (200 µL) as anti-sticking agent were used. After the extraction of the Hg(II) complex (Hg(II):q-Fe(II)-Pc) into thin droplets of ionic liquid, the sample was centrifuged for 4 min at 2000 rpm. The upper aqueous phase was removed and the residue diluted to 250 µL with methanol and transferred to a 250 µL cell for spectrophotometric detection at 280 nm. The linear range of the method is 0.05–1 µg/mL. The limits of detection and quantification is 0.01 and 0.03 µg/mL, respectively. The RSD for the developed method was calculated as 0.78% at 0.50 µg/mL Hg(II). 相似文献
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Incorporation of different conjugated linkers into low band gap polymers based on 5,6‐Bis(octyloxy)‐2,1,3 benzooxadiazole for tuning optoelectronic properties
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Seza Goker Gonul Hizalan Seda Kutkan Yasemin Arslan Udum Ali Cirpan Levent Toppare 《Journal of polymer science. Part A, Polymer chemistry》2016,54(16):2459-2467
Four new 2,1,3‐benzooxadiazole‐based donor–acceptor conjugated polymers, namely poly{9‐(9‐heptadecanyl)‐9H‐carbazole‐alt‐5,6‐bis(octyloxy)‐4,7‐di(selenophen‐2‐yl)benzo[c][1,2,5]oxadiazole)}(PSBSC), poly{9‐(9‐heptadecanyl)‐9H‐carbazole‐alt‐5,6‐bis(octyloxy)‐4,7‐di(furan‐2‐yl)benzo[c][1,2,5]oxadiazole)}(PFBFC), poly{9,9‐dioctyl‐9H‐fluorene‐alt‐5,6‐bis(octyloxy)‐4,7‐di(selenophen‐2‐yl)benzo[c][1,2,5]oxadiazole)}(PSBSFL), and poly{9,9‐dioctyl‐9H‐fluorene‐alt‐5,6‐bis(octyloxy)‐4,7‐di(furan‐2‐yl)benzo[c][1,2,5]oxadiazole)}(PFBFFL), were synthesized via Stille polycondensation reaction. All polymers were found to be soluble in common organic solvents such as chloroform, tetrahydrofuran, and chlorobenzene. Their structures were verified by 1H‐NMR and the molecular weights were determined by gel permeation chromatography (GPC). The polymer films exhibited broad absorption bands. Among all polymers, photovoltaic cells based on the device structure of ITO/PEDOT:PSS/PSBSC:PC71BM(1:3, w/w)/LiF/Al revealed an open‐circuit voltage of 0.62 V, a short circuit current of 7.63 mA cm?2 and a power conversion efficiency of 1.89%. This work demonstrates a good example for tuning absorption range, energy level, and photovoltaic properties of the polymers with different spacers and donor units can offer a simple and effective method to improve the efficiency of PSCs. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 2459–2467 相似文献
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Erhan Zor Yasemin Oztekin Lina Mikoliunaite Jaroslav Voronovic Almira Ramanaviciene Zilvinas Anusevicius Haluk Bingol Arunas Ramanavicius 《Journal of Solid State Electrochemistry》2014,18(6):1529-1536
In this study, two ortho-quinoidal compounds, 1,10-phenanthroline-5,6-dione (PD) and 9,10-phenanthrenequinone (PQ), were examined as electron transfer mediators suitable for amperometric glucose biosensors. The dependences of the electrochemical responses of PD- and PQ-based amperometric glucose biosensors on varied concentrations of glucose were investigated under aerobic and anaerobic conditions. The PD-modified graphite rod (GR) electrode revealed a current response seven times higher than that of the PQ-modified GR electrode. The reactivity indices of ortho-quinoidals assessed by means of B3LYP functional method applying 6-311G(D) basis set showed that the electron-accepting potency for PD was markedly higher as compared with that of PQ. Compared to PQ, considerably higher reactivity of PD has been defined in the reactions with NADP+-ferredoxin reductase (FNR, EC 1.18.1.2) as a model single-electron transfer FAD-dependent enzyme, which provided an additional evidence for PD as a more efficient mediator compared to PQ. This study illustrates that PD can be applied as a redox mediator for glucose oxidase and it could be more suitable for a reagent-less biosensor design than PQ. 相似文献
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Binnur Aydogan Yasemin Yuksel Durmaz Muhammet U. Kahveci Mustafa Uygun M. Atilla Tasdelen Yusuf Yagci 《Macromolecular Symposia》2011,308(1):25-34
Summary: New photoiniting systems for cationic polymerization acting at near UV and visible range are described. The applicability of acylgermanes as a new class of free radical promoters for photoinitiated cationic polymerization is demonstrated. Moreover, the use of substituted vinyl halides as source for readily oxidizable free radicals is presented. The polymerization of vinyl ethers can be initiated by the irradiation of substituted vinyl halides in the presence of Lewis acids such as zinc halide. Furthermore, possibilities for conducting cationic polymerization at visible range by using highly conjugated thiophene derivatives are demonstrated. Mechanistic aspects of all initiating systems are discussed. 相似文献
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Kemal Sancak Yasemin Ünver Hasan Tanak Ismail Değirmencioğlu Esra Dügdü Mustafa Er Şamil Işik 《Journal of inclusion phenomena and macrocyclic chemistry》2010,67(3-4):325-334
A series of new N′-3-(1H-imidazol-1-yl)propylcarbamoyl-4-halogenebenzo hydrazonate (3a–b) were obtained by reaction Ethyl 2-((4-halogene phenyl) (ethoxy) methylene) hydrazinecarboxylate (1) and N-(3-aminopropyl)imidazole (2) at 120–140 °C. Compounds (4a–b) were obtained by the reaction compound 1 and N-(3-aminopropyl)imidazole (2) at 160–180 °C. The structures of compounds 3,4 have been inferred through UV–Vis, IR, 1H/13C NMR, mass spectrometry, elemental analyses, and X-ray crystallography. DFT level 6-31G (d) calculations provided structural information. The electronic structure of compound 3a has been studied by DFT level 6-31G (d) calculations using the X-ray data. The results are accordance with X-ray data. 相似文献