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531.
Mehmet Hakan Morcali Asli Baysal 《International journal of environmental analytical chemistry》2013,93(14):1397-1414
ABSTRACTIn the present study, novel bioconjugated sorbents (peptide and oligo-nucleotide on the cobalt aluminate nanomaterials) were used to remove lead through miniaturised process and the concentration of lead was measured by inductively coupled plasma mass spectrometry. For this aim, lead was collected on sorbent in mini tube, and the influences of experimental conditions (e.g. pH of sample, amount of sorbent, concentration of eluent, foreign ions) and retention parameters on the recovery of the lead element were examined. After the optimisation of experimental parameters, a successful separation was obtained at pH 7.5 with high (>95%) quantitative recovery and high precision (<10% relative standard deviation). Using the proposed bioconjugated sorbents, the lead in sea water and tap water samples could be practically and easily removed with 95% confidence level. The detection limits of this method for lead using oligonucleotide and peptide on the cobalt aluminate nanomaterials were 0.14 and 0.12 µg/L (3σ, N = 10) with sample-matched blanks. This method can be widely used as promising and cost-effective nanomaterials to remove lead from water systems. 相似文献
532.
Tuğba Alp Arıcı Simge Metinoğlu Örüm Yasemin Süzen Demircioğlu Adnan Özcan 《Phosphorus, sulfur, and silicon and the related elements》2013,188(11):721-730
AbstractInorganic–organic hybrid cyclomatrix type polyphosphazene microspheres (poly[cyclotriphosphazene-co-(4,4′-diaminodiphenylmethane)]) (HDMS) and poly[cyclotetraphosphazene-co-4,4′-diaminodiphenylmethane)] (ODMS) were prepared to investigate their possible use as alternative adsorbents for the comparative study on Pb(II) ions removal from aqueous solutions. The structures of the microspheres were elucidated by Fourier Transform Infrared (FTIR) spectroscopy and Dynamic Light Scattering (DLS) measurements, and the surface morphologies were also observed by Scanning Electron Microscopy (SEM). The adsorption of Pb(II) ions onto HDMS and ODMS from aqueous solutions was examined by means of pH, temperature, contact time and concentration. Furthermore, adsorption kinetics and isotherm models were applied and the experimental data fitted well with Langmuir isotherm and pseudo-second-order kinetic models. The maximum adsorption capacities of HDMS and ODMS for Pb(II) ions were obtained as 157.8 and 308.0?mg g?1 at 20?°C and pH 5.5, respectively. 相似文献
533.
Ş. Hakan Üngören Mustafa Saçmacı Cengiz Arıcı Ertan Şahin Taner Arslan Fatma Kandemirli 《Phosphorus, sulfur, and silicon and the related elements》2013,188(11):2877-2890
Novel alkyl substituted 3-(4-benzoyl-1,5-diphenyl-2,3-dihydro-1H-pyrazol-3-yl)-3-oxo-2-(triphenylphosphoranylidene) propanoates (3) were synthesized from 4-benzoyl-1,5-diphenyl-1H-pyrazole-3-carbonylchloride (1) and alkyl (triphenylphosphoranylidene) acetates (2a–b). The synthesized compounds were characterized by elemental analysis, spectroscopic studies (3a–b), and single crystal X-ray diffraction (3a). The mechanism of the reaction between (1) and (2a) was studied by AM1, and the geometrical parameters of the studied molecules were also carried out in B3LYP methods with the standard 6–31G (d,p) basis set. NBO analysis were studied for 1 and 2a B3LYP methods with the standard 6–31G (d,p) basis set. 相似文献
534.
In this study, the radical cyclization reactions of cyclic 1,3-dicarbonyl compounds (1a–c) and α,β-unsaturated alcohols (2a–d) through Mn(OAc)3 were performed. A series of biologically interesting dihydropyrans (3–5) and dihydrofurans (6–18) were synthesized as a result of these reactions. Spiro compounds (19–20) were obtained from the reactions of 1,3-dicarbonyl compounds and (E)-2,4-diphenyl-but-3-en-2-ol (2e). The unique structure of compound 19 was also confirmed by X-ray crystallography. In addition, the antibacterial activities of synthesized compounds were screened against some bacteria. Their zone diameters showed better results than some known antibiotics. 相似文献
535.
Hakan Kandemir 《合成通讯》2013,43(22):2583-2591
A simple and efficient synthesis of novel 3-(benzimidazol-2-yl)- and 3,6-di(benzimidazol-2-yl)-9-ethyl-9H-carbazoles is described. The synthetic approach for the preparation of 2-substituted benzimidazoles 4–8 and bis-benzimidazoles 9–12 was achieved by the condensation of carbazole-3-carbaldehyde 2 and carbazole-3,6-dicarbaldehyde 3 with o-phenyldiamines in dimethylformamide or dimethylsulfoxide in moderate to excellent yield. The identities of synthesized compounds were confirmed using 1H NMR, 13C NMR, infrared (IR), and high-resolution mass spectrometry (HRMS). 相似文献
536.
Apuhan T Terzi EH Kükner A Gök U 《Journal of photochemistry and photobiology. B, Biology》2011,105(1):94-97
Allergic rhinitis is a high-incidence allergic inflammation of the nasal airways that impacts quality of life. Of the numerous therapies used to treat allergic rhinitis, intranasal phototherapy has emerged as a promising new treatment modality for inflammatory airway disease. Phototherapy is widely used for the treatment of immune-mediated skin diseases because its profound immunosuppressive effect inhibits hypersensitivity reactions in the skin. Intranasal phototherapy using a combination of Ultraviolet-A (UVA) and Ultraviolet-B (UVB) plus Visible light (VIS) has been shown to suppress the clinical symptoms of allergic rhinitis, but limited data regarding its adverse effects on the nasal mucosa currently exists. In this study, we demonstrate that UV displays no harmful effects on the nasal mucosa cells of rabbits following 2 weeks of intranasal phototherapy. 相似文献
537.
Three Co(II), Ni(II) and Zn(II) complexes of orotate with the N-methylimidazole ligand were synthesized and characterized by means of elemental and thermal analysis, magnetic susceptibilities, IR, UV-Vis spectroscopic and antimicrobial activity studies. The crystal structures of [Co(HOr)(H2O)2(Nmeim)2]3·H2O (1), [Ni(HOr)(H2O)2(Nmeim)2] (2) and [Zn(HOr)(H2O)(Nmeim)2] (3) were determined by the single crystal X-ray diffraction technique (H3Or = orotic acid and Nmeim = N-methylimidazole). In complexes 1 and 2, the Co(II) and Ni(II) ions have distorted octahedral geometries with two Nmeim, one orotate and two aqua ligands. Complex 3 has a distorted trigonal bipyramidal geometry with two N-methylimidazole, one orotate and one aqua ligands. In the complexes, the orotate is coordinated to the metal(II) ions through the deprotonated nitrogen atom of the pyrimidine ring and the oxygen atom of the carboxylate group as a bidentate ligand. The complexes form a three-dimensional framework by hydrogen bonding, C-H?π and π?π stacking interactions. The MIC values of the complexes against selected microorganisms were determined to be in range 300-2400 μg/mL. 相似文献
538.