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61.
Pezhman Kazemi Mohammad Peydayesh Alireza Bandegi Toraj Mohammadi Omid Bakhtiari 《Chemical Papers》2013,67(7):722-729
An experimental study on the pertraction of methylene blue (MB) through a supported liquid membrane (SLM) using a mixture of mono-(2-etylhexyl) ester of phosphoric acid (M2EHPA) and bis-(2-etylhexyl) ester of phosphoric acid (D2EHPA) and sesame oil as the liquid membrane (LM) was performed. Parameters affecting the pertraction of MB such as initial MB concentration, carrier concentration, feed phase pH, and stripping phase concentration were analyzed. Optimal experimental conditions for MB pertraction (permeability of 5.63 × 10?6) were obtained after a 7 h separation with the MB concentration in the feed phase of 80 mg L?1, D2EHPA/M2EHPA concentration in membrane phase of 40 vol. %, feed pH of 6, and acetic acid concentration in the stripping phase of 0.4 mol L?1. Kinetics of transport and stability of the SLM system were also studied and the mass transfer coefficient for this system was evaluated. Scanning electron microscopy (SEM) was used to morphologically characterize the membrane surface. 相似文献
62.
Ghodsi Mohammadi Ziarani Sakineh Faramarzi Negar Lashgari Alireza Badiei 《Journal of the Iranian Chemical Society》2014,11(3):701-709
Sulfonic acid functionalized SBA-15 (SBA-Pr-SO3H) as a new nanoporous solid acid catalyst was applied in the green one-pot synthesis of spiro[indole-tetrahydropyrano(2,3-d)pyrimidine] derivatives via three-component reaction of isatins, malononitrile or cyanoacetic esters and barbituric acids under solvent-free conditions. SBA-Pr-SO3H was proved to be an efficient heterogeneous nanoporous solid acid catalyst with a pore size of 6 nm, which could be easily handled and removed from the reaction mixture by simple filtration and can be recovered and reused several times without any loss of activity. The advantages of this methodology are high product yields, being environmentally benign, short reaction times, and easy handling. 相似文献
63.
Ranjbarzadeh Ramin Akhgar Alireza Taherialekouhi Roozbeh DOrazio Annunziata Mohammad Sajadi S. Ghaemi Ferial Baleanu Dumitru 《Journal of Thermal Analysis and Calorimetry》2022,147(13):7509-7521
Journal of Thermal Analysis and Calorimetry - In this research, the effect of using GO/ water nanofluid as a coolant fluid in an isothermal heat transfer system was studied. At first, to evaluate... 相似文献
64.
Olga Koba-Ucun Tuba
lmez Hanci Idil Arslan-Alaton Samira Arefi-Oskoui Alireza Khataee Mehmet Kobya Yasin Orooji 《Molecules (Basel, Switzerland)》2021,26(2)
The application of layered double hydroxide (LDH) nanomaterials as catalysts has attracted great interest due to their unique structural features. It also triggered the need to study their fate and behavior in the aquatic environment. In the present study, Zn-Fe nanolayered double hydroxides (Zn-Fe LDHs) were synthesized using a co-precipitation method and characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), and nitrogen adsorption-desorption analyses. The toxicity of the home-made Zn-Fe LDHs catalyst was examined by employing a variety of aquatic organisms from different trophic levels, namely the marine photobacterium Vibrio fischeri, the freshwater microalga Pseudokirchneriella subcapitata, the freshwater crustacean Daphnia magna, and the duckweed Spirodela polyrhiza. From the experimental results, it was evident that the acute toxicity of the catalyst depended on the exposure time and type of selected test organism. Zn-Fe LDHs toxicity was also affected by its physical state in suspension, chemical composition, as well as interaction with the bioassay test medium. 相似文献
65.
Mazloum-Ardakani Mohammad Sabaghian Fariba Khoshroo Alireza Abolhasani Mahboobe Naeimi Hossein 《Ionics》2015,21(1):239-250
Ionics - A novel carbon paste electrode (CPE) modified with 2,2′-[1,7–heptanediylbis(nitrilomethylidene)]-bis(4-hydroxyphenol) (DHB) and carbon nanotubes (CNTs) was prepared. At first,... 相似文献
66.
A novel organic-inorganic hybrid optical sensor (SBA-NCO) was designed and synthesized through immobilization of isocyanatopropyl-triethoxysilane and 1-amino-naphthalene onto the surface of SBA-15 by post-grafting method. The characterization of materials using XRD, TEM, N2 adsorption-desorption, and FT-IR techniques confirmed the successful attachment of organic moieties and preserving original structure of SBA-15 after modification step. Fluorescence experiments demonstrated that SBA-NCO was a highly selective optical sensor for the detection of Fe3+ directly in water over a wide range of metal cations including Na+, Mg2+, Al3+, K+, Ca2+, Cr3+, Mn2+, Fe2+, Co2+, Ni2+, Cu2+, Zn2+, Cd2+, Hg2+, and Pb2+ in a wide pH values. 相似文献
67.
68.
This paper presents the oil uptake of porous sorbent polymer sheets consisting of ultra‐high molecular weight polyethylene. A comprehensive set of experiments are performed showing the saturation contact time, retention value, mechanical properties, oil pick‐up ratio, pick‐up density, and dynamic dripping profile. Kinetic modeling of the oil sorption is also provided. The experimental results show a good correlation with the pseudo‐second order model. The sheets exhibit high oil uptake speeds, requiring less than 2 min in contact with the oil to reach saturation. The sheets fulfill the criteria of high uptake kinetics, high sorption capacity, and high mechanical strength simultaneously. Those characteristics enable their use in practical spill response. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
69.
Alireza Najafi Chermahini Mehdi Rezapour Abbas Teimouri 《Journal of inclusion phenomena and macrocyclic chemistry》2014,79(1-2):205-214
A density functional theory based on interaction of alkali metal cations (Li+, Na+, K+, Rb+ and Cs+) with cyclic peptides constructed from 3 or 4 alanine molecule (CyAla3 and CyAla4), has been investigated using mixed basis set (C, H, O, Li+, Na+ and K+ using 6-31+G(d), and the heavier cations: Rb+ and Cs+ using LANL2DZ). The minimum energy structures, binding energies, and various thermodynamic parameters of free ligands and their metal cations complexes have been determined with B3LYP and CAM-B3LYP functionals. The order of interaction energies were found to be Li+ > K+ > Na+ > Rb+ > Cs+ and Li+ > Na+ > K+ ? Rb+ > Cs+, calculated at CAM-B3LYP level for the M/CyAla3 and M/CyAla4 complexes, respectively. Their selectivity trend shows that the highest cation selectivity for Li+ over other alkali metal ions has been achieved on the basis of thermodynamic analysis. The main types of driving force host–guest interactions are investigated, the electron-donating O offers lone pair electrons to the contacting LP* of alkali metal cations. 相似文献
70.
Use of citric acid as a chelating agent and fuel, ammonium nitrate as fuel, boric acid as flux material and silica as supports, CaWO4:Ln3+@SiO2 (Ln = Er and Tm) nanoparticles were synthesized via a combustion reaction at 800 °C. Characterization of the samples was performed by X-ray diffractometer (XRD), reflectance UV–Vis spectrophotometer, fluorescence spectrophotometer (PL) and transmission electron microscope (TEM). XRD patterns showed that tetragonal crystalline structure of scheelite and silica supports were formed, and that the formation of a silica support could enhance the luminescence intensity of CaWO4:Ln3+. The reflectance UV–Vis and PL spectra indicated the broad absorption band of WO4 2? groups about 240 nm, the WO4 2? wide excitation band with maximum at 240 nm, a broad emission band of WO4 2? with maximum about 420 nm, and characteristic emissions of Ln3+ ions. According to the TEM analysis, CaWO4:Er3+@SiO2 and CaWO4:Tm3+@SiO2 nanoparticles have almost the same morphology with average particle sizes about 50 nm. 相似文献