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21.
Removal of heavy metals and bacteria from aqueous solution by novel hydroxyapatite/zeolite nanocomposite,preparation, and characterization 总被引:1,自引:0,他引:1
Mojgan Zendehdel Bahareh Shoshtari-Yeganeh Giuseppe Cruciani 《Journal of the Iranian Chemical Society》2016,13(10):1915-1930
In this study, a HAp/NaP nanocomposite was prepared by adding a synthesized nano-hydroxyapatite to zeolite NaP gel in the hydrothermal condition and used for the removal of lead(II) and cadmium(II) ions from aqueous solution. HAp/zeolite nanocomposite was then characterized by Fourier transform infrared spectroscopy, X-ray diffraction and Rietveld method, scanning electron microscope, energy-dispersive X-ray analysis, and surface area and thermal analyses. Results suggested that the nanocomposite crystals of HAp were dispersed onto the zeolite external surface and/or encapsulated within the zeolite channels and pores. The potential of the composite in adsorption of heavy metals was investigated by using batch experiment. The metal concentration in the equilibrium C e (mg/g) after adsorption with nanocomposite of HAp/NaP was analyzed using flame atomic adsorption spectrometry. The adsorption experiments were carried out at pH of 3–9. The influences of contact time, initial concentration, dose, and temperature on the adsorption of lead and cadmium ions were also studied. Results show that these nanocomposites have further adsorption related to NaP and HAp. They have great potential (about 95 %) for Pb(II) and Cd(II) adsorption at room temperature. The equilibrium process was described by Frendlich, Langmuir, Temkin, and Dubinin–Radushkevich (D-R) models. The kinetics data were successfully fitted by a pseudo-second-order model. The in vitro antibacterial activity of these composites was evaluated against Bacillus subtilis (as Gram-positive bacteria) and Pseudomonas aeruginosa (as Gram-negative bacteria) and compared with standard drugs that show inhibition on bacterial growth. 相似文献
22.
Today the synthesis of silver nanoparticles is very common due to their numerous applications in various fields. Silver nanoparticles have unique properties such as: optical and catalytic properties, which, depend on the size and shape of the produced nanoparticles. So, today the production of silver nanoparticles with different shapes which have various uses in different fields such as medicine, are noted by many researchers. This article, is an attempt to present an overview of the shape-controlled synthesis of silver nanoparticles using various methods. 相似文献
23.
Farough Nasiri Morteza Bidar Bahareh Atashkar 《Monatshefte für Chemie / Chemical Monthly》2009,140(4):463-466
Abstract The reaction between dibenzoylacetylene and enol systems, such as acetylaceton or cyclohexane-1,3-dione in the presence of
triphenylphosphine in THF/H2O, leads to 4-acetyl-3-benzoyl-1-phenyl-1,5-hexanedione and 2-hydroxy-3-(2-oxo-2-phenylethyl)-2-phenyl-3,5,6,7-tetrahydro-1-benzofuran-4(2H)-one. Subsequently, these compounds undergo cyclization and elemination reactions in acidic dichloromethane at room temperature
to produce known highly functionalized furan derivatives.
Graphical abstract
相似文献
24.
Hamid Reza Farmani Mohammad Hossein Mosslemin Bahareh Sadeghi 《Molecular diversity》2018,22(3):743-749
Rapid, efficient, simple and green procedure for the synthesis of 4,5-dihydro-1H-pyrazole-1-carbothioamides via the multicomponent reaction of aryl aldehydes, acetophenones and thiosemicarbazide in water in the presence of tetrabutylammonium hydroxide under microwave irradiation is reported. 相似文献
25.
Mohammad Bagher Majnooni Bahareh Mohammadi Ronak Jalili Gholamreza Bahrami 《液相色谱法及相关技术杂志》2016,39(19-20):877-881
A new high-performance liquid chromatographic method is described for the determination of fatty acids in seed oils. The method was based on precolumn derivatization with 9-fluorenylmethyl chloroformate as a labeling agent and fluorescence detection. Fatty acids were extracted from the samples and subjected to derivatization with the reagent at 60°C for 10?min. The chromatographic separation of 14 fatty acids (C10–C22) was achieved on a combined loading compression octadecyl sulfate (CLC-ODS) column with a run time of 30?min. Three-step gradient elution of a mobile phase consisted of acetonitrile and water was used, and the signal was monitored at excitation and emission wavelengths of 265 and 315?nm, respectively. The method indicated favorable sensitivity and reproducibility for fatty acids’ derivatives. The detection limits, at a signal-to-noise ratio of 3, were 0.01–0.05?µg/ml and relative standard deviations (RSDs) were less than 0.27%. Excellent linear responses were observed with coefficients of 0.9995. This method was applied to quantify fatty acids in white, brown, and black sesame seeds’ oil. 相似文献
26.
Natural biopolymers from plant sources contain many impurities (e.g., fat, protein, fiber, natural pigment and endogenous enzymes), therefore, an efficient purification process is recommended to minimize these impurities and consequently improve the functional properties of the biopolymer. The main objective of the present study was to investigate the effect of different purification techniques on the yield, protein content, solubility, water- and oil-holding capacity of a heteropolysaccharide-protein biopolymer obtained from durian seed. Four different purification methods using different chemicals and solvents (i.e., A (isopropanol and ethanol), B (isopropanol and acetone), C (saturated barium hydroxide), and D (Fehling solution)] to liberate the purified biopolymer from its crude form were compared. In most cases, the purification process significantly (p < 0.05) improved the physicochemical properties of heteropolysaccharide-protein biopolymer from durian fruit seed. The present work showed that the precipitation using isopropanol and acetone (Method B) resulted in the highest purification yield among all the tested purification techniques. The precipitation using saturated barium hydroxide (Method C) led to induce the highest solubility and relatively high capacity of water absorption. The current study reveals that the precipitation using Fehling solution (Method D) most efficiently eliminates the protein fraction, thus providing more pure biopolymer suitable for biological applications. 相似文献
27.
Gholam Hossein Rounaghi Bahareh Nouri Somayeh Tarahomi 《Journal of inclusion phenomena and macrocyclic chemistry》2012,72(3-4):331-338
The complexation reaction of N-phenylaza-15-crown-5 (PhA15C5) with UO2 2+ cation was studied in acetonitrile–methanol (AN–MeOH), acetonitrile–butanol (AN–BuOH), acetonitrile–dimethylformamide (AN–DMF) and methanol–propylencarbonate (MeOH–PC) binary solutions, at different temperatures by conductometry method. The conductance data show that the stoichiometry of the complex formed between PhA15C5 with UO2 2+ cation in most cases is 1:1 [M:L], but in some solvent systems a 1:2 [M:L2] complex is formed in solutions. The results revealed that, the stability constant of (PhA15C5·UO2)2+ complex in the binary mixed solvents varies in the order: AN–BuOH>AN–MeOH>AN–DMF. In the case of the pure organic solvents, the sequence of the stability of the complex changes as: AN>PC>BuOH>DMF. A non-linear relationship was observed for changes of logKf of (PhA15C5·UO2)2+ complex versus the composition of the binary mixed solvents. The corresponding standard thermodynamic parameters (ΔHc°, ΔSc°) were obtained from temperature dependence of the stability constant. The results show that the values and also the sign of these parameters are influenced by the nature and composition of the mixed solvents. 相似文献
28.
Ahmed N Suresh V Shirinfar B Geronimo I Bist A Hwang IC Kim KS 《Organic & biomolecular chemistry》2012,10(10):2094-2100
Cyclo-bis-(urea-3,6-dichlorocarbazole) (1) forms a 1 : 2 complex with CH(3)CO(2)(-) and H(2)PO(4)(-) through hydrogen bonding with the two urea moieties, resulting in fluorescence enhancement via a combined photoinduced electron transfer (PET) and energy transfer mechanism. The binding mechanism involves a conformational change of the two urea receptors to a trans orientation after binding of the first anion, which facilitates the second interaction. 相似文献
29.
An insight to the molecular interactions of the FDA approved HIV PR drugs against L38L↑N↑L PR mutant
Zainab K. Sanusi Thavendran Govender Glenn E. M. Maguire Sibusiso B. Maseko Johnson Lin Hendrik G. Kruger Bahareh Honarparvar 《Journal of computer-aided molecular design》2018,32(3):459-471
The aspartate protease of the human immune deficiency type-1 virus (HIV-1) has become a crucial antiviral target in which many useful antiretroviral inhibitors have been developed. However, it seems the emergence of new HIV-1 PR mutations enhances drug resistance, hence, the available FDA approved drugs show less activity towards the protease. A mutation and insertion designated L38L↑N↑L PR was recently reported from subtype of C-SA HIV-1. An integrated two-layered ONIOM (QM:MM) method was employed in this study to examine the binding affinities of the nine HIV PR inhibitors against this mutant. The computed binding free energies as well as experimental data revealed a reduced inhibitory activity towards the L38L↑N↑L PR in comparison with subtype C-SA HIV-1 PR. This observation suggests that the insertion and mutations significantly affect the binding affinities or characteristics of the HIV PIs and/or parent PR. The same trend for the computational binding free energies was observed for eight of the nine inhibitors with respect to the experimental binding free energies. The outcome of this study shows that ONIOM method can be used as a reliable computational approach to rationalize lead compounds against specific targets. The nature of the intermolecular interactions in terms of the host–guest hydrogen bond interactions is discussed using the atoms in molecules (AIM) analysis. Natural bond orbital analysis was also used to determine the extent of charge transfer between the QM region of the L38L↑N↑L PR enzyme and FDA approved drugs. AIM analysis showed that the interaction between the QM region of the L38L↑N↑L PR and FDA approved drugs are electrostatic dominant, the bond stability computed from the NBO analysis supports the results from the AIM application. Future studies will focus on the improvement of the computational model by considering explicit water molecules in the active pocket. We believe that this approach has the potential to provide information that will aid in the design of much improved HIV-1 PR antiviral drugs. 相似文献
30.
A facile method for the synthesis of various propargylamines derivatives with different structural parts has been reported. The reaction has consisted of one-pot coupling between aldehydes, secondary amines and terminal alkynes using CuCl as a catalyst and choline chloride/urea DES as a cheap and biocompatible reaction media. The procedure is free of using toxic solvents and used CuCl as an available, inexpensive and non-toxic catalyst. Using this methodology, 15 different propargylamine derivatives were successfully synthesized at 60 °C in 15 hr, mostly in good yields. 相似文献