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In this study, combined technique of solid-phase extraction based on multi-walled carbon nanotubes with bio-coacervation extraction (SPE-MWCNT-BCAE) has been developed as a new sample preparation method for the determination of atrazine from water samples. The proposed method involves two steps: analyte enrichment on the solid sorbent and subsequently elution of the analyte by an appropriate solvent. Multi-walled carbon nanotubes (MWCNTs) were used as the sorbent. They have high specific surface area, nano-scale structure and high diffusion rate. The second step is based on the use of bioaggregates for analyte re-enrichment, which consists of biosurfactants and ionic liquid. This method follows the principles of green chemistry. Parameters affecting the extraction efficiency were optimized. Under optimum conditions, the enrichment factor was 176. The linear dynamic range (LDR) and limit of detection (LOD) were 2–100 µg L?1 and 0.66 µg L?1, respectively. The relative standard deviation (RSD) for six replicate measurements was 3.8%. The method was applied to the determination of ultratrace levels of atrazine in environmental water samples with satisfactory results. 相似文献
104.
Sajjad Abbasi Ali Sarafraz-Yazdi Amirhassan Amiri Ferial Ghaemi 《Journal of the Iranian Chemical Society》2018,15(1):153-161
We describe a magnetic nanocomposite that consists of Fe3O4/carbon nanosphere/polypyrrole (Fe3O4/CNS/PPy). The synthesized nanocomposites were characterized by scanning electron microscopy, transmission electron microscopy, and Fourier transform infrared spectroscopy. The nanocomposite was successfully applied to extract of the polycyclic aromatic hydrocarbons (PAHs) from water samples. Compared to Fe3O4/PPy, the Fe3O4/CNS/PPy nanocomposite exhibits improved properties in terms of extraction. The amount of adsorbent, salt effect, extraction time, desorption time, type, and the volume of desorption solvent were optimized. Following the desorption of the extracted analytes, the PAHs (i.e., naphthalene, 2-methylnaphthalene, 2-bromonaphthalene, fluorene, and anthracene) were quantified by gas chromatography–flame ionization detector. The PAHs can be determined in 0.05–100.00 ng mL?1 concentration range, with limits of detection (at an S/N ratio of 3) ranging from 0.01 to 0.05 ng mL?1. The repeatability of the method was investigated with relative standard deviations of lower than 9.9% (n = 5). Also, the recoveries from spiked real water samples were in the range of 88.9–99.0%. The results indicate that the novel material can be successfully applied for the extraction and analysis of PAHs from water samples. 相似文献
105.
An efficient strategy for the synthesis of benzamides from acetamides and aryl iodides using 1 mol% Pd (OAc)2 as catalyst and Cr (CO)6 as CO‐precursor is described. This new synthetic methodology displays high functional group tolerance on both substrates and avoids the need for ligands, reducing agents, or other additives. The corresponding products were obtained in good to excellent yields at atmospheric pressure under mild reaction conditions. 相似文献
106.
Enhanced properties of photovoltaic devices tailored with novel supramolecular structures based on reduced graphene oxide nanosheets grafted/functionalized with thiophenic materials
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Samira Agbolaghi Sara Ebrahimi Bakhshali Massoumi Saleheh Abbaspoor Raana Sarvari Farhang Abbasi 《Journal of Polymer Science.Polymer Physics》2017,55(24):1877-1889
For verifying the influence of donor–acceptor supramolecules on photovoltaic properties, different hybrids were designed and used in organic solar cells. In this respect, reduced graphene oxide (rGO) was functionalization with 2‐thiophene acetic acid (rGO‐f‐TAA) and grafted with poly(3‐dodecylthiophene) (rGO‐g‐PDDT) and poly(3‐thiophene ethanol) (rGO‐g‐PTEt) to manipulate orientation of poly(3‐hexylthiophene) (P3HT) assemblies. Face‐on, edge‐on, and flat‐on orientations were detected for assembled P3HTs on rGO and its functionalized and grafted derivatives, respectively. Alteration of P3HT orientation from face‐on to flat‐on enhanced current density (J sc), fill factor (FF), and power conversion efficiency (PCE) and thus J sc = 7.11 mA cm?2, FF = 47%, and PCE = 2.14% were acquired. By adding phenyl‐C71‐butyric acid methyl ester (PC71BM) to active layers composed of pre‐designed P3HT/rGO, P3HT/rGO‐f‐TAA, P3HT/rGO‐g‐PDDT, and P3HT/rGO‐g‐PTEt hybrids, photovoltaic characteristics further improved, demonstrating that supramolecules appropriately mediated in P3HT:PC71BM solar cells. Phase separation was more intensified in best‐performing photovoltaic systems. Larger P3HT crystals assembled onto grafted rGOs (95–143 nm) may have acted as convenient templates for the larger and more intensified phase separation in P3HT:PCBM films. The best performances were reached for P3HT:P3HT/rGO‐g‐PDDT:PCBM (J sc = 9.45 mA cm?2, FF = 54%, and PCE = 3.16%) and P3HT:P3HT/rGO‐g‐PTEt:PCBM (J sc = 9.32 mA cm?2, FF = 53%, and PCE = 3.11%) photovoltaic systems. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2017 , 55 , 1877–1889 相似文献
107.
Reza Omidyan Maryam Abbasi Gholamhassan Azimi 《International journal of quantum chemistry》2019,119(3):e25793
New platinum(II) complex with picolinate (pic) and 2-phenyl naphtothiazole (pntl) ligand as the guest material has been designed and its capability for OLED applications have been examined. Also, we have studied the effects of different substitutions (ie, electron-withdrawing and electron donating groups) on naphtothiazole moiety on optovoltaic characters. We have employed density functional theoretical (B3LYP/DFT) methods to reveal the photophysical and structure properties relationships with the typical host material. The valence MO energies, vertical and adiabatic triplet energy, reorganization energy, and triplet exciton generation fraction (χ T) have been extensively studied to exploring high phosphorescence efficiency in OLEDs. It has been predicted that substituted systems are good candidates for OLED applications as well as their parent system. 相似文献
108.
Abbasi Malek Kruger Alexander Y. Théra Michel 《Set-Valued and Variational Analysis》2021,29(3):701-719
Set-Valued and Variational Analysis - This paper proposes three enlargements of the conventional Moreau–Rockafellar subdifferential: the sup-, sup?- and symmetric subdifferentials. They... 相似文献
109.
Batoul Arabsorkhi Hassan Sereshti Alireza Abbasi 《Journal of separation science》2019,42(8):1500-1508
A new composite nanofiber of polyacrylonitrile doped with copper benzene‐1,3,5‐tricarboxylate metal‐organic framework was fabricated by electrospinning and used as a microsorbent in the solid‐phase extraction of trace tetracycline. The chemical structure of the adsorbent was studied by X‐ray diffraction, scanning electron microscopy, Fourier transform infrared spectroscopy, Brunauer–Emmett–Teller surface area analysis, and Barrett‐Joyner‐Halenda pore size and volume analysis techniques. The significant parameters of the method including desorption solvent kind and volume, adsorbent mass, pH, and salt percentage were investigated. At the optimized conditions, the linear range was 8–1000 μg/L with a determination coefficient (R2) of 0.9954. The limits of detection and quantification were 2.40 and 8.00 μg/L, respectively. The inter‐ and intraday precisions were 4.7 and 3.4%, respectively. The developed extraction method was followed by high‐performance liquid chromatography and applied for the determination of tetracycline in human blood plasma, and good relative recoveries (97.3‐104.5%) were obtained. 相似文献
110.
Effect of Partially Hydrolyzed Kappa-Casein on Physicochemical and Sensory Properties of Heated Milk
Marjan Nouri Soleiman Abbasi Mehdi Aminafshar Homa Behmadi 《Journal of Dispersion Science and Technology》2013,34(8):1204-1209
The chemical, physical, and sensory characteristics of renneted skim milk (RSM) containing partially hydrolyzed κ-casein were assessed and compared with skim milk (control). Rennet was added to heated milk (60°C for 15 minutes) at seven concentrations from 0.1 to 0.7 mL rennet/100 mL milk followed by heating to 63°C for 30 minutes in order to inactivate the rennet. The RSM samples had higher viscosity as well as whiter, yellower, and greener color in comparison with control sample. The range of size distribution of casein aggregates was larger than that of skim milk, while being within the range of fat mimetics. 相似文献