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Abbas Afkhami Farzaneh Soltani-Felehgari Tayyebeh Madrakian Hamed Ghaedi Majid Rezaeivala 《Analytica chimica acta》2013
A new chemically modified carbon paste electrode was constructed and used for rapid, simple, accurate, selective and highly sensitive simultaneous determination of cadmium, copper and mercury using square wave anodic stripping voltammetry (SWASV). The carbon paste electrode was modified by N,N′-bis(3-(2-thenylidenimino)propyl)piperazine coated silica nanoparticles. Compared with carbon paste electrode, the stripping peak currents had a significant increase at the modified electrode. Under the optimized conditions (deposition potential, −1.100 V vs. Ag/AgCl; deposition time, 60 s; resting time, 10 s; SW frequency, 25 Hz; pulse amplitude, 0.15 V; dc voltage step height, 4.4 mV), the detection limit was 0.3, 0.1 and 0.05 ng mL−1 for the determination of Cd2+, Cu2+ and Hg2+, respectively. The complexation reaction of the ligand with several metal cations in methanol was studied and the stability constants of the complexes were obtained. The effects of different cations and anions on the simultaneous determination of metal ions were studied and it was found that the electrode is highly selective for the simultaneous determination of Cd2+, Cu2+ and Hg2+. Furthermore, the present method was applied to the determination of Cd2+, Cu2+ and Hg2+ in water and some foodstuff samples. 相似文献
44.
Hassan Keypour Ahmad Ali Dehghani-Firouzabadi Majid Rezaeivala Sadegh Salehzadeh 《合成通讯》2013,43(7):1136-1142
A new Schiff base cryptand (L) has been prepared via [2 + 2] condensation of 1,3,5-tris(2-formylphenoxymethyl)benzene (1) with 1,3,5-tris(aminomethyl)benzene trishydrochloride (2) in the presence of Ba(II) ion. The analytical data show that the Ba(II) cation is not retained by the product. Thus it seems that the role of the Ba(II) ion is to organize the transition state preceding the formation of the cryptand. 相似文献
45.
Thiols can be readily converted to their corresponding nitrosothiols with a combination of oxalic acid and sodium nitrite in t-butanol at room temperature (26-30°C). The reaction mixture could be solidified with decreasing its temperature to, 15°C and was stored for several days without any destruction of the nitrosothiols. 相似文献
46.
Mohammad Ali Zolfigol Maryam Kiany-borazjani Majid M. Sadeghi Hamid Reza Memarian Iraj Mohammadpoor-baltork 《合成通讯》2013,43(16):2945-2950
A combination of NaHSO4.H2O and NaNO2 in the presence of wet SiO2 was used as an effective oxidizing agent for the oxidation of dihydropyridines to their corresponding pyridine derivatives at room temperature with excellent yields. 相似文献
47.
Melamine trisulfonic acid, which is easily prepared by the reaction of melamine with neat chlorosulfonic acid, is able to efficiently catalyze the chemoselective methoxymethylation of alcohols with dimethoxymethane (DMM). All reactions were performed under mild and completely heterogeneous reaction conditions in good to high yields. 相似文献
48.
《Comptes Rendus Chimie》2014,17(2):118-123
Poly(N-bromo-N-ethyl-benzene-1,3-disulfonamide) [PBBS] and N,N,N’,N’-tetrabromobenzene-1,3-disulfonamide [TBBDA] were used as efficient catalysts for the one-pot synthesis of 3-substituted indoles in good to high yields from indole, aldehydes, and arylamines under solid-state conditions at room temperature. 相似文献
49.
Tayyebeh Madrakian Abbas Afkhami Nahid Rezvani-jalal Mazaher Ahmadi 《Journal of the Iranian Chemical Society》2014,11(2):489-498
The potential removal and preconcentration of lead(II), cadmium(II), and chromium(III) ions from wastewaters were investigated and explored. Magnetite nanoparticles were chemically modified with p-nitro aniline. The aniline-coated magnetite nanoparticles (ANMNPs) were fully characterized by FT-IR, XRD, SEM, and TEM measurements. Batch studies were performed to address various experimental parameters for the removal and determination of these ions. ANMNPs showed high tendency to investigated metal ions, in this order: Cr(III) > Cd(II) > Pb(II), owing to the strong contribution of surface loaded aniline. The potential applications of ANMNPs adsorbent for removal and preconcentration of Pb(II), Cr(III), and Cd(II) from wastewaters as well as drinking tap water samples were successfully accomplished giving recovery values of (98–101 %), without any noticeable interference of the wastewater or drinking tap water matrices. 相似文献
50.
Ghoorchian Arash Madrakian Tayyebeh Afkhami Abbas Bagheri Hasan 《Journal of Solid State Electrochemistry》2021,25(4):1217-1229
Journal of Solid State Electrochemistry - The increasing efforts devoted to fabricating electrochromic (EC) devices have motivated a lot of studies to develop new EC materials. Herein, we introduce... 相似文献