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371.
A simple and one-pot method for the synthesis of octahydroquinazolinone is reported.Cu/SiO2 in refluxing ethanol catalyzes this three-component condensation reaction to afford the corresponding quinazolinones in good yields. 相似文献
372.
A chelating resin based on modified poly (styrene‐alt‐maleic anhydride) with 3‐aminobenzoic acid was synthesized. This modified resin was further reacted by 1,2‐diaminoethane or 1,3‐diaminopropane in the presence of ultrasonic irradiation to prepare tridimensional chelating resin for the removal of heavy metal ions from aqueous solutions. The adsorption behavior of Fe(II), Cu(II), Zn(II) and Pb(II) ions was investigated by synthesized chelating resins in various pH. Among the synthesized resins, CSMA‐AB1 and CSMA‐AB2 demonstrated a high affinity for the selected metal ions compared to SMA‐AB, and the order of removal percentage changes as follow: Fe(II) > Cu(II) > Zn(II) > Pb(II). The adsorption of all metal ions in acidic medium was moderate, and it was favored at the pH value of 6 and 7. Also, the prepared resins were examined for removal of metal ions from industrial wastewater and were shown to have a very efficient adsorption in the case of Cu(II), Fe(II) and Pb(II); however, the adsorption of Zn(II) was lower than others. The resin was characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, X‐ray diffraction analysis and thermogravimetric analysis/derivative thermogravimetry. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
373.
Karim Asadpour‐Zeynali Mir Reza Majidi Parvaneh Najafi‐Marandi Zinalabedin Norysaray 《中国化学会会志》2013,60(10):1253-1259
We report a new and simple approach based on an experimental design method for the preparation of pencil‐lead electrode modified with bismuth thin film. The fabrication process consists of reduction of bismuth on the surface of electrode with potentiostate method. Response surface methodology was developed as experimental strategies for modeling and optimization of the influence of some variables on the performance of modified electrode. The electrocatalytic behavior of this modified electrode was exploited as a sensitive detection system for the mercury‐free reduction and determination of metronidazole in pharmaceutical and biological samples by using differential pulse voltammetry and amperometry methods. 相似文献
374.
Leili Jalili‐Baleh Narges Mohammadi Mehdi Khoobi Leila Ma'mani Alireza Foroumadi Abbas Shafiee 《Helvetica chimica acta》2013,96(8):1601-1609
Various monospiro‐2‐amino‐4H‐pyran derivatives have been synthesized in high yields (via three‐component coupling of ninhydrin or different isatins with malononitrile and 1,3‐dicarbonyl compounds) in the presence of catalytic amount of propane‐1‐sulfonic acid‐modified magnetic hydroxyapatite nanoparticles in H2O. Due to easy magnetic removal of nanocatalyst and applying of H2O as solvent, this protocol enhanced product purity, and promised economic as well as environmental benefits, exemplifying a waste‐free chemistry. More importantly, the catalyst could be easily recycled for more than five times without loss of activity. 相似文献
375.
Majid M. Heravi Masoumeh Zakeri Narges Karimi Mina Saeedi Hossien A. Oskooie Niloofar Tavakoli-Hosieni 《合成通讯》2013,43(13):1998-2006
2,4,5-Trisubstituted imidazoles have been synthesized in excellent yields (85–95%) in the presence of 5 mol% of [(CH2)4SO3HMIM][HSO4] as a Brønsted acidic ionic liquid. 相似文献
376.
Alireza Najafi Chermahini Abbas Teimouri Alireza Salimi Beni 《Structural chemistry》2011,22(1):175-181
Detailed investigation of the tautomerism of all possible forms of tetrazole thion (A and E) and its tetrazole forms (B–D) induced by proton transfer in the gas phase, in a continuum solvent, and in a microhydrated environment with 1 explicit
water molecule was carried out by calculations at MP2, QCISD, CBS-Q, CBS-QB3, and density functional theory (DFT). It was
found that in the gas phase and solvent tetrazole thion (form A) is the most stable isomer. In addition variation of dipole moments was studied in the gas phase and in the solvent. Water
molecule was gradually put in different regions in the vicinity of five isomers. It was found that water can forms different
hydrogen bonding with molecule. 相似文献
377.
In this work, we use the most recent publicly available type Ia supernova (SNIa) compilations and H(z) data. A well formulated cosmological model based on Bianchi type I (BI) metric is implemented in the presence of the Ricci dark energy model. Using the maximum likelihood technique, we estimate the present value of Hubble's constant H0 = 70.339 ± 0.743, matter density parameter ${{\rm{\Omega }}}_{{m}_{0}}=0.297\pm 0.031$, anisotropy parameter ${{\rm{\Omega }}}_{{\sigma }_{0}}=\,$−0.004 01 ± 0.001 07 within $1\sigma ^{\prime} $ confidence level by bounding our derived model with recent joint Pantheon and H(z) data. We have constrained the present value of the equation of state parameter as ωde = −1.17 joint with the observational data. The present value of the deceleration parameter of the Universe in the derived model is obtained as ${q}_{0}=-{0.749}_{-0.086}^{+0.076}$. Transition redshift is also derived as ${z}_{\mathrm{tr}}\sim 0.551$ with the recent observations (Pantheon + H(z)) datasets. Finally, we compare the anisotropy effects on the evolution of H(z) for the proposed model under consideration with different observational datasets. 相似文献
378.
Rastegari Arezoo Safavi Maliheh Vafadarnejad Fahimeh Najafi Zahra Hariri Roshanak Bukhari Syed Nasir Abbas Iraji Aida Edraki Najmeh Firuzi Omidreza Saeedi Mina Mahdavi Mohammad Akbarzadeh Tahmineh 《Molecular diversity》2022,26(1):409-428
Molecular Diversity - Alzheimer’s disease (AD) is now ranked as the third leading cause of death after heart disease and cancer. There is no definite cure for AD due to the multi-factorial... 相似文献
379.
In this paper, we study three different space-time fractional models of the Schrödinger equation. By using the properties of conformable derivative and fractional complex transform, the bright, dark and singular optical solitons for conformable space–time fractional nonlinear \((1+1)\)-dimensional Schrödinger models are determined. 相似文献
380.
A.R. Najafi M.R. Rahimpour A.H. Jahanmiri R. Roostaazad D. Arabian M. Soleimani Z. Jamshidnejad 《Colloids and surfaces. B, Biointerfaces》2011,82(1):33-39
The potential of an indigenous bacterial strain isolated from an Iranian oil field for the production of biosurfactant was investigated in this study. After isolation, the bacterium was characterized to be Paenibacillus alvei by biochemical tests and 16S ribotyping. The biosurfactant, which was produced by this bacterium, was able to lower the surface tension of media to 35 mN/m. Accordingly, thin layer chromatography (TLC) and FT-IR has been carried out to determine compositional analysis of the produced biosurfactant. After all the tests related to characterization of the biosurfactant produced by the isolated bacterium, it was characterized as lipopeptide derivative. The combination of central composite rotatable design (CCRD) and response surface methodology (RSM) was exploited to optimize biosurfactant production. Therefore, variations of four impressive parameters, pH, temperature, glucose and salinity concentrations were selected for optimization of growth conditions. The empirical model developed through RSM in terms of effective operational factors mentioned above was found to be adequate to describe the biosurfactant production. A maximum reduction in surface tension was obtained under the optimal conditions of 13.03 g/l glucose concentration, 34.76 °C, 51.39 g/l total salt concentration and medium pH 6.89. 相似文献