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81.
Olga KOBA UCUN Bahareh MONTAZERI dil ARSLAN ALATON Tuba
LMEZ HANCI 《Turkish Journal of Chemistry》2021,45(2):269
Zero-valent iron (ZVI)- and zero-valent aluminium (ZVA)-activated persulfate (PS) oxidation procedure was applied to remove the industrial pollutants 3,5-dichlorophenol (3,5-DCP; 12.27 µM) and 2,4-dichloroaniline (2,4-DCA; 12.34 µM) from aqueous solutions. The effects of PS concentration and pH were investigated to optimize heterogeneous treatment systems. Negligible removals were obtained for both pollutants by individual applications of nanoparticles (1 g/L) and PS (1.00 mM). PS activation with ZVI resulted in 59% (1.00 mM PS; 1 g/L ZVI; pH 5.0; 120 min) and 100% (0.75 mM PS; 1 g/L ZVI; pH 5.0; 80 min) 3,5-DCP and 2,4-DCA removals, respectively. The ZVA/PS treatment system gave rise to only 31% 3,5-DCP (1.00 mM PS; 1 g/L ZVA; pH 3.0; 120 min) and 47% 2,4-DCA (0.25 mM PS; 1 g/L ZVA; pH 3.0; 120 min) removals. The pH decreases from 5.0 to 3.0 and from 3.0 to 1.5 enhanced contaminant removals for ZVI/PS and ZVA/PS treatments, respectively. Pollutant removal rates were in correlation with the consumption rates of the oxidants. Metal ion (Al, Fe) release increased in the presence of PS and with decreasing pH. 相似文献
82.
Ambrosi A Chee SY Khezri B Webster RD Sofer Z Pumera M 《Angewandte Chemie (International ed. in English)》2012,51(2):500-503
All at C? Graphenes prepared by the top-down exfoliation of graphite are shown to contain metallic impurities (see scheme, metal impurities shown as black dots). These impurities may dominate their properties and can have a negative influence on their potential applications. 相似文献
83.
Bi Bi Fatemeh Mirjalili Mohammad M. Hashemi Bahareh Sadeghi Hamideh Emtiazi 《中国化学会会志》2009,56(2):386-391
Enolizable ketones have been reacted in a one‐pot method with aromatic aldehydes, acetyl chloride and acetonitrile at room temperature in the presence of SnCl4/SiO2 to furnish the corresponding β‐acet‐amidoketones in improved yields. Acetylation of an aromatic hydroxyl group was observed while using 4‐hydroxybenzaldehyde or vanillin and the corresponding β‐acetamidoketones were isolated in an excellent yield. 相似文献
84.
Bahareh?Fahimirad Yalda?Rangraz Ali?Elhampour Firouzeh?NematiEmail authorView authors OrcID profile 《Mikrochimica acta》2018,185(12):560
Diphenyl diselenide was immobilized on chitosan loaded with magnetite (Fe3O4) nanoparticles to give an efficient and cost-effective nanosorbent for the preconcentration of Pb(II), Cd(II), Ni(II) and Cu(II) ions by using effervescent salt-assisted dispersive magnetic micro solid-phase extraction (EA-DM-μSPE). The metal ions were desorbed from the sorbent with 3M nitric acid and then quantified via microflame AAS. The main parameters affecting the extraction were optimized using a one-at-a-time method. Under optimum condition, the limits of detection, linear dynamic ranges, and relative standard deviations (for n?=?3) are as following: Pb(II): 2.0 ng·mL?1; 6.3–900 ng·mL?1; 1.5%. Cd(II): 0.15 ng·mL?1; 0.7–85 ng·mL?1, 3.2%; Ni(II): 1.6 ng·mL?1,.6.0–600. ng·mL?1, 4.1%; Cu(II): 1.2 ng·mL?1, 3.0–300 ng·mL?1, 2.2%. The nanosorbent can be reused at least 4 times. 相似文献
85.
Mohammad M. Mojtahedi Hassan Abassi M. Saeed Abaee Bahareh Mohebali 《Monatshefte für Chemie / Chemical Monthly》2006,37(5):455-458
Solvent-free ring opening of 1,2-epoxides with thiols using catalytic amounts of lithium perchlorate affords high yields of
β-hydroxy sulfides. Nucleophilic attack of the thiols occurs regioselectively at the sterically less hindered side of the
epoxides. 相似文献
86.
Ali Nemati Kharat Fereshteh Rajabi Kouchi Bahareh Tamaddoni Jahromi 《Journal of Coordination Chemistry》2016,69(1):12-19
Rhodium-catalyzed hydroformylation of 1-octene in the presence of different phosphine and phosphine oxide ligands has been investigated. The molecular structure of new phosphine ligand, fluorenylidine methyl phenyl diphenylphosphine, was determined by single-crystal X-ray crystallography. Parameters such as different ligands, molar ratio of ligand to rhodium complex, ratio of olefin to rhodium complex, pressure of CO : H2 mixture, and time of the reaction were studied. The linear aldehyde was the main product when the phosphine ligands were used as auxiliary ligands while the selectivity was changed to the branched products when the related phosphine oxide ligands were used. Under optimized reaction conditions, in the presence of [Rh(acac)(CO)(Ph3P)]-di(1-naphthyl)phenyl phosphine oxide, conversion of 1-octene reached 97% with 87% selectivity of branched aldehyde. 相似文献
87.
Diphenyl vinyl sulfonium salt and chiral amido-ketones undergo highly diastereoselective epoxy-annulation reactions in good yield. The use of a chiral vinyl sulfonium salt dominates the stereochemical outcome of the annulation reaction (reagent control is greater than substrate control), and this has allowed the kinetic resolution of racemic amido-ketones to be achieved. 相似文献
88.
Silica-supported boron trifluoride (BF3·SiO2) is an efficient, readily available and reusable catalyst for the synthesis of 1,2,4,5-tetrasubstituted imidazoles using benzil, an aromatic aldehyde and an amine in the presence of ammonium acetate. This one-pot procedure is very simple, affording good to excellent yields. 相似文献
89.
Saira Khatoon Aggeliki Vgenopoulou Muhammad Moazzam Naseer Bahareh Shirinfar Benson M. Kariuki Necmi Dege Nisar Ahmed 《Journal of heterocyclic chemistry》2019,56(4):1388-1392
Several indoline derivatives with specific geometries are biologically active and have inhibitor properties. Many indolines are a key part of natural products. Much attention has been focused on the development of synthetic routes for their easy access. Current synthesis depends largely on metal catalysis, iodine reagents, and Oxone. To date, no synthetic route has been established that is metal‐free, reagent‐free, and environmentally friendly and provides a base for green chemistry. Here, we report the first facile metal‐free and reagent‐free synthesis of indoline derivatives, which could potentially be influential in the design of new biologically active compounds. The synthesis proceeds through intramolecular amination between a urea nucleophile and unactivated alkene. The ring closure occurs in a few hours in the presence of pre‐dried silica gel and gives good yields of indolines products, but in the absence of silica gel, the ring closure occurred overnight with stirring in dry solvent. An electron withdrawing group at the substituted aryl moiety of ureas increases the hydrogen bond donor ability of substrates that mediate the internal proton transfer at the terminal alkene and results in facile amination to give the indoline product with an “in plane” orientation of the carbonyl group and aromatic part of indoline framework. Such orientation in indolines is important for potent biological activities. 相似文献
90.
Kinetics and related studies of the formation of 2,3‐dihydroquinazolin‐4(1H)‐ones in the presence of different benzaldehyde derivatives 下载免费PDF全文
Bahareh Mostafa Mehdi Shahraki Sayyed Mostafa Habibi‐Khorassani 《Journal of Physical Organic Chemistry》2018,31(3)
The kinetics and activation parameters for the reaction between 2‐amino‐benzamide and some benzaldehyde derivatives in the presence of formic acid have been reported and discussed. A linear plot of lnk vs l/T showed that the reactions obey the Arrhenius equation. Both the Arrhenius and the Eyring equations were used to calculate the activation energy. The effect of nitro groups was studied on different positions of benzaldehyde. For all substituents, the reactions followed second‐order kinetics, and the partial orders of reactions were recognized with respect to each reactant. Comparisons between the magnitudes of ΔH? and TΔS?showed that the reactions were enthalpy controlled. The validity of the isokinetic relationship and the compensation effect was tested, and the isokinetic temperature (β) was obtained. A linear enthalpy‐entropy plot (ΔH?versusΔS?) showed that the compensation effect is established, and this process occurs via a same mechanism across a series of reactions. From the Van't Hoff and Exner's plots, the isokinetic temperature was obtained. 相似文献