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231.
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
232.
Somayyeh Piri Farideh Piri Bahare Rajabi Sahar Ebrahimi Abbasali Zamani Mohammad Reza Yaftian 《中国化学会会志》2015,62(11):1045-1052
Aluminum oxide/polyaniline nanocomposite is prepared by a new and one‐pot method including in situ electrooxidation of aluminum and electropolymerization of aniline. The product has been characterized by elemental analysis, FT‐IR spectroscopy, X‐ray diffraction (XRD), Field Emission Scanning Electron Micrographs (FESEM), and Transmission Electron Micrographs (TEM) techniques. ICP‐OES was used for determination of aluminum in the prepared nanocomposite. A porous structure of the prepared composite has been shown by FESEM images. TEM of the product confirms the presence of exfoliated aluminum oxide nanofibers. The adsorption potentials of the prepared nanocomposite towards Cu2+, Pb2+, Zn2+, Cd2+, Ni2+ and Co2+ ions were evaluated in batch adsorption experiments. The results show that the adsorption efficiency is controlled by aqueous phase pH. The experimental data was well interpreted by considering the Langmuir model. The kinetics of the adsorption processes can be well interpreted by pseudo‐second‐order equation. 相似文献
233.
Peyman Salehi Mahdi Ayyari Morteza Bararjanian Samad Nejad Ebrahimi Atousa Aliahmadi 《Journal of the Iranian Chemical Society》2014,11(3):607-613
A series of novel 2,3-dihydroquinazolin-4(1H)-ones was synthesized by a three-component reaction between dehydroabietylamine (DHA) diterpene, isatoic anhydride and different aromatic aldehydes in the presence of a catalytic amount of p-toluenesulfonic acid (13 mol%). Diastereomeric products were separated by preparative thin-layer chromatography and their structures were characterized by 1H and 13C NMR, HMQC, IR and HR-ESI-MS. Antioxidant activities of the synthesized compounds were assessed by two different methods including DPPH and β-carotene-linoleic acid bleaching assays. Antibacterial activities of the compounds were also evaluated against two Gram-positive and one Gram-negative bacterial strains and in the case of Bacillus cereus a considerable inhibitory effect (MIC 4–16 μg/ml) was observed. 相似文献
234.
Fast Quantitation of Target Analytes in Small Volumes of Complex Samples by Matrix‐Compatible Solid‐Phase Microextraction Devices 下载免费PDF全文
Dr. Hamed Piri‐Moghadam Fardin Ahmadi MSc. German Augusto Gómez‐Ríos Dr. Ezel Boyacı MSc. Nathaly Reyes‐Garcés Dr. Ali Aghakhani Dr. Barbara Bojko Prof. Janusz Pawliszyn 《Angewandte Chemie (International ed. in English)》2016,55(26):7510-7514
Herein we report the development of solid‐phase microextraction (SPME) devices designed to perform fast extraction/enrichment of target analytes present in small volumes of complex matrices (i.e. V≤10 μL). Micro‐sampling was performed with the use of etched metal tips coated with a thin layer of biocompatible nano‐structured polypyrrole (PPy), or by using coated blade spray (CBS) devices. These devices can be coupled either to liquid chromatography (LC), or directly to mass spectrometry (MS) via dedicated interfaces. The reported results demonstrated that the whole analytical procedure can be carried out within a few minutes with high sensitivity and quantitation precision, and can be used to sample from various biological matrices such as blood, urine, or Allium cepa L single‐cells. 相似文献
235.
Somayeh Tajik Hadi Beitollahi Zahra Dourandish Peyman Mohammadzadeh Jahani Iran Sheikhshoaie Mohammad Bagher Askari Parisa Salarizadeh Fariba Garkani Nejad Dokyoon Kim Soo Young Kim Rajender S. Varma Mohammadreza Shokouhimehr 《Electroanalysis》2022,34(7):1065-1091
Non-precious transition metal oxide nanomaterials offer numerous opportunities for various cost-effective electrochemical applications. This review article features the design and advancement of such nanomaterials with unique features applied for the fabrication of electrochemical devices. Also, it discusses various new syntheses of transition metal oxide nanoparticles (TMO NPs) via multiple chemicophysical and biological procedures. Further, the novel appliances of the TMO NPs with varying sizes and morphologies are appraised. The advantages and challenges of a number of investigations on the TMO NPs towards electrochemical applications are addressed with their standpoint of cost-effectiveness, applicability, and the efficiency of the introduced nanostructures for the industrial applications. 相似文献
236.
Mohammad Foad Abazari Navid Nasiri Fatemeh Nejati Mina Kohandani Nazanin Hajati‐Birgani Solmaz Sadeghi Peyman Piri Fatemeh Soleimanifar Mostafa Rezaei‐Tavirani Vahid Mansouri 《先进技术聚合物》2021,32(1):272-281
After about three decades of experience, tissue engineering has become one of the most important approaches in reconstructive medical research to treat non‐self‐healing bone injuries and lesions. Herein, nanofibrous composite scaffolds fabricated by electrospinning, which containing of poly(L‐lactic acid) (PLLA), graphene oxide (GO), and bone morphogenetic protein 2 (BMP2) for bone tissue engineering applications. After structural evaluations, adipose tissue derived mesenchymal stem cells (AT‐MSCs) were applied to monitor scaffold's biological behavior and osteoinductivity properties. All fabricated scaffolds had nanofibrous structure with interconnected pores, bead free, and well mechanical properties. But the best biological behavior including cell attachment, protein adsorption, and support cells proliferation was detected by PLLA‐GO‐BMP2 nanofibrous scaffold compared to the PLLA and PLLA‐GO. Moreover, detected ALP activity, calcium content and expression level of bone‐related gene markers in AT‐MSCs grown on PLLA‐GO‐BMP2 nanofibrous scaffold was also significantly promoted in compression with the cells grown on other scaffolds. In fact, the simultaneous presence of two factors, GO and BMP2, in the PLLA nanofibrous scaffold structure has a synergistic effect and therefore has a promising potential for tissue engineering applications in the repair of bone lesions. 相似文献