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81.
Sedigheh Kashian Ali Asghar Fathivand Reza Pourimani 《Journal of Radioanalytical and Nuclear Chemistry》2018,317(1):87-91
In this study, five of popularly used medicinal plants as Cichorium intybus, Anethum graveolens seed, Thymus vulgaris, Fumaria officinalis and Hibiscus sabdariffa Syn: Hibiscus gossypifolius were prepared from Herbal Pharmacies in Tehran. The amounts of Al, Br, Ca, Cl, Cr, Fe, K, Mg, Mn, Na, V and Zn in samples were determined using instrumental neutron activation analysis. In this method, Tehran research reactor as a neutron source and relative INAA have been used as the analysis procedure. Highest levels of Cr (5 mg/kg), Ca (28316 mg/kg) and Mg (4134 mg/kg) were detected in Thymus vulgaris and F1umaria officinalis, respectively. 相似文献
82.
Nahid?TavakkoliEmail author Nasrin?Soltani Faezeh?Shahdost-fard Mahbobeh?Ramezani Hossein?Salavati Mohammad?Reza?Jalali 《Mikrochimica acta》2018,185(10):479
A highly selective electrochemical sensor was fabricated based on a modified carbon paste electrode with zinc ferrite nanoparticles (ZnFe2O4 NPs). The nanocomposite has attractive properties such as high surface-to-volume ratio and good electrocatalytic activity towards the drugs acetaminophen (AC), epinephrine (EP), and melatonin (MT), best at working voltages of 0.35, 0.09 and 0.55 V (vs. Ag/AgCl), respectively. The linear ranges (and detection limits) are 6.5–135 (0.4) μmol L?1 for AC, 5–100 (0.7) μmol L?1 for EP, and 6.5–145 (3) μmol L?1 for MT. 相似文献
83.
Mahmoud Roushani Zahra Saedi Fatemeh Hamdi Hamid Reza Rajabi 《Journal of the Iranian Chemical Society》2018,15(10):2241-2249
In this study, a new Cr(III)-imprinted polymer (Cr(III)-IIP) is prepared from CrCl3·6H2O, methacrylic acid functional monomer, ethyleneglycoldimethacrylate cross-linking agent, 2,2?-azobisisobutyronitrile radical initiator and 2,2-(azanediylbis (ethane-2,1-diyl))bis(isoindoline-1,3-dione) ligand. To obtain the maximum adsorption capacity, the optimum condition was studied through pH, type and concentration of eluent, IIP weight, sample volume as well as the adsorption and desorption times. The Cr(III) ion content was determined via flame atomic absorption spectrometer. In optimum conditions, the adsorption capacity of the IIP for Cr(III) was obtained to be 74.65 mg g?1, using 50 mg of IIP and the initial pH solution of 3.0. Both the adsorption and desorption times for quantitative analyses of Cr(III) ions were 15 and 5 min; respectively. After elution of the adsorbed ions by 3 mL of 4 mol L?1 HNO3 aqueous solution, the established IIP-based SPE procedure provides a reasonable pre-concentration factor of 100. The IIP-based pre-concentration method provides a low detection limit of 1.7 µg L?1 with good repeatability (RSD?=?3.22%). Reusability studies confirmed that synthesis IIP is reusable and recoverable up to six cycles. According to the selectivity experiments, it was concluded that the prepared sorbent possesses more affinity toward Cr(III) ions than other ions such as Al3+, Pb2+, Cu2+, Mn2+, Fe2+, Zn2+, and Ni2+ ions. To evaluate the potential applicability of the proposed separation method, the pre-concentration and determination of trace amounts of Cr(III) were performed successfully in food samples with complex matrices, a bestial sample (i.e. cow liver) and an herbal product (i.e., broccoli) as real samples. 相似文献
84.
Ali Reza Ghiasvand Sana Abdolhosseini Nahid Heidari Brett Paull 《Journal of the Iranian Chemical Society》2018,15(11):2585-2592
The unique features of nanostructured polypyrrole, conductivity enhancement effect of silver nanoparticles and high polar adsorptivity of polyethylene glycol were merged into polypyrrole/silver/polyethylene glycol (PPy/Ag/PEG) nanocomposite. It was synthesized and simultaneously coated on the surface of a stainless-steel fiber using an amended electropolymerization procedure. Before coating, the fiber substrate was made porous and sticky by allocating platinum dots on the surface of the stainless-steel fiber using the electrophoretic method. The prepared fiber was applied for the extraction of carvacrol and thymol (the most important antioxidants in medicinal plants) through an electroenhanced direct-immersion solid-phase microextraction (EE-DI-SPME) sampling strategy, followed by GC-FID quantification. To achieve the best efficiency, the effectual experimental variables including pH of sample solution, applied voltage, extraction temperature and time, stirring rate, and ionic strength were investigated. Under the optimal experimental conditions, the calibration curves were linear over the range of 0.5–30 µg mL?1 for thymol and 0.01–30 µg mL?1 for carvacrol. The detection limits (3Sb) and relative standard deviation (RSD%, n?=?6) were obtained to be 0.15, 0.003 µg mL?1 and 10.2, 8.7% for thymol and carvacrol, respectively. The results demonstrated the priority of the proposed fiber compared with polypyrrole and polyacrylate fibers, in terms of extraction efficiency, durability and stability. The developed method was successfully employed for the analysis of thymol and carvacrol in medicinal plants. 相似文献
85.
Milani Saeideh Ghaemimanesh Fatemeh Salimi Ali Hadavi Reza Bayat Ali Ahmad Alirezapour Behrouz Rabbani Hodjattallah 《Journal of Radioanalytical and Nuclear Chemistry》2018,316(1):267-273
Journal of Radioanalytical and Nuclear Chemistry - Receptor tyrosine kinase Ror1 is widely expressed during embryogenesis but it is absent within most mature tissues. However, expression of Ror1... 相似文献
86.
Atieh Khosravi Mohammad Reza Khani Elham Dejban Goy Babak Shokri 《Plasma Chemistry and Plasma Processing》2018,38(2):365-378
In present paper, an atmospheric-pressure low-temperature plasma treatment of pyrolysis fuel oil (PFO) was investigated in dielectric barrier discharge plasma torch reactor. The effect of the applied voltage and the volume of feedstock, as the main parameters, on the cracking of PFO were studied. By increasing the applied voltage from 10 to 16 kV, the production rate of hydrocarbons containing methane, ethylene, acetylene, propane, propylene, and C4 rise 18 times. In this case, the production rate of hydrogen increases by approximately 14 times and reaches 7.27 × 10?3 mol/min for 16 kV. In the feedstock volume investigation, based on limitation of reactor volume, the production rate of hydrocarbons decreased from 0.44 × 10?3 to 0.15 × 10?3 mol/min by increasing volume of feedstock from 1 to 5 cc. 相似文献
87.
Morteza Hosseini Mehdi Khoobi Roghayeh Tarasi Mohammad Reza Ganjali 《Research on Chemical Intermediates》2018,44(9):5031-5042
A rhodamine-conjugated coumarin (L) was used in designing a selective fluorescence chemosensor for the determination of trace amounts of Cr3+ ions in acetonitrile–water (MeCN/H2O (90:10, %v/v) solutions. The intensity of the fluoresce emission of the chemosensor is intensified upon addition of Cr3+ ions in MeCN/H2O (90:10, %v/v) solutions, due to the formation of a selective 1:1 complex between L and Cr3+ ions. The fluorescence enhancement versus Cr3+ concentration has been found to be linear from 1.0?×?10?7 to 1.8?×?10?5 M and a detection limit of 7.5?×?10?8 M. The proposed fluorescent probe proved to be highly selective towards Cr3+ ions as compared to other common metal ions and could be successfully applied to the determination of Cr3+ concentrations in some water and wastewater samples. 相似文献
88.
Fe3O4@SiO2@propyltriethoxysilane@o‐phenylendiamine as an environmentally‐benign functionalized silica‐coated magnetic organometallic nanomaterial has been synthesized and characterized by Fourier transforms infrared (FT‐IR) spectroscopy, scanning electron microscopy (SEM) images and energy dispersive X‐ray (EDX) and vibrating sample magnetometer (VSM) analyses. Then, its catalytic activity was investigated for the one‐pot three‐component condensation reaction between dimedone, malononitrile and various substituted aromatic aldehydes to afford the corresponding 2‐amino‐4H‐chromene derivatives under mild reaction conditions. This nanocatalyst can be easily recovered from the reaction mixture by using a magnet and reused for at least five times without significant decrease in catalytic activity. 相似文献
89.
Ahmad Reza Bagheri Mehrorang Ghaedi Kheibar Dashtian Shaaker Hajati Ali Akbar Bazrafshan 《应用有机金属化学》2018,32(1)
TiO2 nanoparticles deposited on activated carbon (TiO2–NP–AC) was prepared and characterized by XRD and SEM analysis. Subsequently, simultaneous ultrasound‐assisted adsorption of Cu2+ and Cr3+ ions onto TiO2‐NPs‐AC after complexation via eriochrome cyanine R (ECR) has been investigated with UV–Vis and FAA spectrophotometer. Spectra overlapping of the ECR‐Cu and ECR‐Cr complex was resolve by derivative spectrophotometric technique. The effects of various parameters such as initial Cu2+ (A) and Cr3+ (B) ions concentrations, TiO2‐NPs‐AC mass (C), sonication time (D) and pH (E) on the removal percentage were investigated and optimized by central composite design (CCD). The optimize conditions were set as: 4.21 min, 0.019 mg, 20.02 and 13.22 mg L?1 and 6.63 for sonication time, TiO2–NP–AC mass, initial Cr3+ and Cu2+ ions concentration and pH, respectively. The experimental equilibrium data fitting to Langmuir, Freundlich, Temkin and Dubinin–Radushkevich models show that the Langmuir model is a good and suitable model for evaluation and the actual behavior of adsorption process and maximum adsorption capacity of 105.26 and 93.46 mg g?1 were obtained for Cu2+ and Cr3+ ions, respectively. Kinetic evaluation of experimental data showed that the adsorption processes followed well pseudo second order and intraparticle diffusion models. 相似文献
90.
Arefeh Dadras M. Reza Naimi‐Jamal Firouz Matloubi Moghaddam Seyed Ebrahim Ayati 《应用有机金属化学》2018,32(2)
Aryl halides and especially inactive aryl chlorides were coupled to benzenoid aromatic rings in a Suzuki–Miyaura coupling reaction in the absence of organic solvents and toxic phosphine ligands. The reaction was catalysed by a recoverable magnetic nanocatalyst, Pd@Fe3O4, in aqueous media. This method is green, and the catalyst is easily removed from the reaction media using an external magnetic field and can be re‐used at least 10 times without any considerable loss in its activity. The catalyst was characterized using scanning and transmission electron microscopies, thermogravimetric analysis, inductively coupled plasma spectroscopy, Fourier transform infrared spectroscopy, CHN analysis, X‐ray diffraction and vibrating sample magnetometry. 相似文献