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201.
Design of a novel optical sensor for determination of trace amounts of copper by UV–visible spectrophotometry in real samples
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Eslam Pourbasheer Somayeh Morsali Zhila Azari Mohammad Ali Karimi Mohammad Reza Ganjali 《应用有机金属化学》2018,32(3)
A new optical chemical sensor is established for sensitive and selective spectrophotometric detection of copper based on the immobilization of 3‐(2‐methyl‐2,3‐dihydro‐1,3‐benzothiezol‐2‐yl)‐2H‐chromen‐2‐one on a triacetylcellulose membrane. Copper ions react with the immobilized ligand and cause an increase in the absorption of the membrane at 550 nm in universal buffer solution at pH = 6. The effects of pH, indicator concentration and reaction time on the immobilization of the ligand were studied. This optode exhibits a linear range of 7.0 × 10?7 to 1 × 10?4 mol l?1 of copper ion concentration with a limit of detection of 3.0 × 10?7 mol l?1. The response time of the newly designed optode is within 3 min. The effect of different possible interfering species was investigated and it was found that the sensor has very good selectivity. The proposed sensor benefits from advantages such as low cost, high stability, low detection limit, fast response time, reproducibility, relatively long lifetime, and good selectivity for Cu2+ ion determination among a large number of alkali, alkaline earth, transition and heavy metal ions. The sensor can readily be regenerated with thiourea solution and its response is reversible and reproducible (relative standard deviation < 1.4%). The proposed optode was applied successfully for the determination of Cu(II) in various samples. 相似文献
202.
Reza Ranjbar-Karimi Somayeh Hashemi-Uderji Roghayeh Danesteh 《Journal of the Iranian Chemical Society》2012,9(5):747-755
Novel [6,6,6] ring fused tricyclic systems can be readily synthesized in one-pot annulation reaction of pentafluoropyridine or 4-phenylsulfonyl tetrafluoropyridine with appropriate difunctional nitrogen and oxygen nucleophiles attached to aromatic rings. Reaction of 4-phenylsulfonyl tetrafluoropyridine with 2,6-diaminopyridine gave [6,5,6] ring fused systems arising from a tandem SNAr and cyclisation process. From this investigation, di- and trifluorinated quinoxaline and dioxine scaffolds were synthesized. 相似文献
203.
A novel carbon paste electrode modified with graphene nanosheets and an ionic liquid (n-hexyl-3-methylimidazolium hexafluoro phosphate) was fabricated and used for the electrochemical study of mangiferin for the first time. This modified electrode offers a considerable improvement in voltammetric sensitivity toward mangiferin, compared to the bare electrode. Square wave voltammetry (SWV) exhibits a linear dynamic range from 5.0?×?10?8 to 2.0?×?10?4 M and a detection limit of 20.0 nM for mangiferin. Finally, the proposed method was successfully applied to the determination of mangiferin in real samples such as serum and urine. 相似文献
204.
Ali Darehkordi Mahmood Javanmiri Somayeh Ghazi Shokrollah Assar 《Journal of fluorine chemistry》2011,132(4):263-268
N-substituted trifluoroacetimidoyl chlorides were used for the synthesis of new piperazinylquinolone derivatives. These reactions provided N-aryl-2,2,2-trifluoroacetimidoyl piperazinylquinolone derivatives in good yields. Two selected compounds were evaluated for their antibacterial activities. These compounds displayed good antibacterial activities. 相似文献
205.
Akbari N Daneshjoo S Akbari J Khajeh K 《Applied biochemistry and biotechnology》2011,165(3-4):785-794
A novel extracellular lipase with organic solvent tolerance was isolated from a local Pseudomonas species. The lipase gene was cloned and expressed in Escherichia coli as a heterologous host and purified by affinity chromatography. The activity of purified lipase was investigated in the presence of imidazolium-based ionic liquids (ILs) such as EMIM[Cl], BMIM[Cl], and HMIM[Cl]. It has been found that the activity of treated lipase with ILs was higher than untreated control in the hydrolysis reaction. Also, the results indicated that the enzymatic activity strongly depends on IL concentration in reaction media. The best concentration of the IL was 30%, 45%, and 50% (v/v) for HMIM[Cl], BMIM[Cl], and EMIM[Cl], respectively. Additionally, the enzyme exhibited excellent stability in the presence of 25% of n-hexane, toluene, acetone, and t-butanol. The optimum values of pH and temperature were determined 10 and 55 °C, respectively. The K (m) and V (max) values were calculated 0.4 mM and 1.92 U/ml, respectively, using p-nitrophenyl palmitate as substrate. With respect to the biochemical properties of the newly isolated lipase such as high-level stability and noticeable activity in the presence of organic solvents and ionic liquids, the newly isolated lipase seems to be a good candidate for environmental and industrial processes carried out in non-aqueous media. 相似文献
206.
Maasoumeh Jafarpour Abdolreza Rezaeifard Somayeh Gazkar Maryam Danehchin 《Transition Metal Chemistry》2011,36(7):685-690
Eight Schiff base compounds were prepared by condensation of 1-amino-2-propanol with different benzaldehydes in water. One
of the Schiff bases, (z)-N-bezylidene-2-hydroxypropane-1-amine (HL1), was used as a bidentate ligand for preparation of a zirconium complex (Zr(L1)2Cl2). The complex has been used as a catalyst for efficient synthesis of wide variety of indole derivatives in EtOH under mild
conditions. The turnover number and reusability of the catalyst indicate that it has high efficiency and is fairly stable
under the reaction conditions. 相似文献
207.
Alireza Salabat Rahmat Sadeghi Somayeh Tiani Moghadam Bahman Jamehbozorg 《The Journal of chemical thermodynamics》2011,43(10):1525-1529
The partitioning behavior of l-methionine has been studied in aqueous two-phase systems of (poly(propylene glycol) + sodium phosphate salts + H2O) at different temperatures. The salts used were sodium di-hydrogen phosphate (NaH2PO4), di-sodium hydrogen phosphate (Na2HPO4) and tri-sodium phosphate (Na3PO4). The effects of tie line length, salt type, and temperature on the partition coefficient of this amino acid have been studied. In addition, thermodynamic parameters (ΔH°, ΔS° and ΔG°) as a function of temperature were calculated. The results showed that increasing tie line length led to decreasing of the partition coefficient. We also showed that the partition coefficients of the amino acid in the systems containing Na3PO4 are greater than the other two salts. Moreover, it is verified that increasing temperature led to decreasing the partition coefficient. The experimental partition coefficient data are correlated using a modified virial-type model. 相似文献
208.
Somayeh Karimi Navid Mostoufi Rahmat Sotudeh-Gharebagh 《Journal of Optimization Theory and Applications》2014,160(3):1020-1026
The honey bee mating optimization (HBMO) algorithm is presented and tested with various test functions, and its performance is compared with the genetic algorithm (GA). It is shown that the HBMO algorithm can overcome the weaknesses of the GA. The HBMO converges faster than the GA. Even when the HMBO starts from a more improper initial condition than the GA, it can reach a better solution in a smaller number of function evaluations. Furthermore, in some cases, the GA was not able to reach the global minimum. 相似文献
209.
Akbar Mobinikhaledi Naser Foroughifar Somayeh Faghihi 《Phosphorus, sulfur, and silicon and the related elements》2013,188(7):1837-1842
Treatment of 2-aminopyridine ( 1 ) with chloroacetyl chloride in dry benzene gave 2-chloro-N-(pyridin-2-yl)acetamide ( 3 ), which on further reaction with potassium thiocyanate gave 2-imino-3-(pyridin-2-yl)thiazolidin-4-one ( 4 ) as an intermediate compound for the synthesis of pyridin-2-yl substituted 2-imino-thiazolidine-4-one derivatives. Cyclocondensation reaction of ( 4 ) with a series of aromatic aldehydes gave 5-arylidene derivatives of pyridin-2-yl substituted 2-imino-thiazolidine-4-ones 5a–j . 1 H and 13C NMR spectroscopy, as well as elemental analyses, were used for the identification of these new compounds. 相似文献
210.
Pirsaheb Meghdad Mohammadi Somayeh Khodarahmi Reza Hoseinkhani Zohreh Mansouri Kamran Payandeh Mehrdad 《Journal of fluorescence》2022,32(5):1733-1741
Journal of Fluorescence - In this research, DNA-modified carbon dots (CDs) were exploited to construct a fluorescence assay for breast cancer genes (BRCA1, a potential marker for cancer diagnosis)... 相似文献