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991.
Hamid Heshmati Hossein Ghanadzadeh Gilani Amir Haidary 《Journal of Dispersion Science and Technology》2014,35(4):501-509
In this study, an amidoximated chelating ion exchange resin was prepared by poly-acrylonitrile (PAN) grafted potato starch. The adsorbent characterizations such as specific surface area, pore volume, average pore radius, and Fourier transform infrared (FTIR) spectrum of the resin were measured. The effects of pH, adsorbent dosage, contact time, initial concentration of thorium ion, and temperature on adsorption of thorium ion from aqueous solutions were investigated. Four isotherm models including Langmuir, Freundlich, Dubinin-Radushkevich, and Temkin were applied to analyze the equilibrium isotherm data. The results showed that Langmuir and Temkin models had a good agreement with experimental data. The maximum capacity of the adsorbent using the Langmuir isotherm model was 227.27 mg · g?1. The kinetic models like pseudo-first-order, pseudo-second-order, Elovich, and intraparticle were examined to describe the adsorption process. The kinetics of the adsorption process was found to follow the pseudo-second-order kinetic model. The thermodynamic parameters (ΔG°, ΔH°, ΔS°) were also calculated using equilibrium constant values at various temperatures (25, 35, 45, 55°C) and the positive value for ΔH° showed an endothermic adsorption process. The study suggests that the prepared adsorbent has promising potential for the removal of thorium from wastewaters. 相似文献
992.
Mohammad R. Davarpanah Hossein A. Khoshhosn Mohsen Harati S. Attar Nosrati Masoumeh Zoghi Mohammad Mazidi M. Ghannadi Maragheh 《Journal of Radioanalytical and Nuclear Chemistry》2014,302(1):69-77
Hydroxyapatite was applied as a carrier adsorbing 90Y3+ ions for 90Y-HA colloid production. The radiopharmaceutical colloid was prepared by adding an acidic solution of 90YCl3 to HA suspension in saline solution. Effective parameters on labeling of 90Y-HA were evaluated. Adsorption and cation-exchange properties were studied using inductively coupled plasma elemental analysis and N2 adsorption–desorption isotherm method. Radionuclidic purity was over 99.9 %. Labeling yield and radiochemical purity were >99 %. Radiochemical purity was evaluated also in human albumin for 7 days at 37 °C. Biodistribution studies have shown complete retention of injected radioactivity at the administration site up to 72 h. 相似文献
993.
绿色可磁性分离二氧化硅包裹镍铁尖晶石负载硫酸氢铁纳米粒子催化剂用于合成1,8-二氧十氢吖啶合成Amir Khojastehnezhad,Mohammad Rahimizadeh,简 总被引:1,自引:0,他引:1
Amir Khojastehnezhad Mohammad Rahimizadeh Hossein Eshghi Farid Moeinpour Mehdi Bakavoli 《催化学报》2014,35(3):376-382
A new magnetically separable catalyst consisting of ferric hydrogen sulfate supported on silica-coated nickel ferrite nanoparticles was prepared. The synthesized catalyst was characterized using vibrating sample magnetometry, X-ray diffraction, transmission electron microscopy, scanning electron microscopy, and Fourier transform infrared spectroscopy. This new magnetic catalyst was shown to be an efficient heterogeneous catalyst for the synthesis of 1,8-dioxodecahydroacridines under solvent-free conditions. The catalyst is readily recovered by simple magnetic decantation and can be recycled several times with no significant loss of catalytic activity. 相似文献
994.
A carbon paste electrode modified with 2‐((7‐(2,5-dihydrobenzylideneamino)heptylimino)methyl) benzene‐1,4‐diol(DHB) and carbon nanotubes were used to simultaneously determine the concen-trations of isoproterenol(IP), uric acid(UA), and folic acid(FA) in solution. First, cyclic voltammetry was used to investigate the redox properties of the modified electrode at various scan rates. Next, the mediated oxidation of IP at the modified electrode is described. At the optimum pH of 7.0, the oxidation of IP occurs at a potential about 90 mV less than that of an unmodified carbon paste elec-trode. Based on the results of differential pulse voltammetry(DPV), the oxidation of IP showed a dynamic range between 10 and 6000 μmol/L, and a detection limit of 1.24 μmol/L. Finally, DPV was used to simultaneously determine the concentrations of IP, UA, and FA in solution at the modified electrode. 相似文献
995.
Amir Hossein Haghighi Milad Sheydaei Ahmad Allahbakhsh Marzieh Ghatarband Fatemeh Sadat Hosseini 《Journal of Thermal Analysis and Calorimetry》2014,117(2):525-535
In this study, the influences of expanded graphite oxide (EG) nanosheets presence with and without surfactant on structural and thermal performance of poly(ethylene disulfide) (PEDS)-based nanocomposites are investigated. Sodium dodecylbenzenesulfonate (SDBS) is used as a surfactant for the preparation of modified-EG nanosheets. The structural, morphological, and thermal properties of prepared nanocomposites are studied using X-ray diffraction (XRD), scanning electron microscopy, and differential scanning calorimetry techniques, respectively. XRD patterns of nanocomposites reveal that a high degree of expanded graphite nanosheets dispersion is achieved with and without surface modification using in situ polymerization method. Moreover, the presence of immobilized polysulfide chains near the interface region of nanosheets is suggested as a possible reason for the observed increase in the number of semi-crystalline organic fractions in the structure of PEDS via EG nanosheets incorporation. In addition, the morphology of SDBS-modified-EG loaded nanocomposite shows a smoother fracture surface than unmodified-nanosheets reinforced nanocomposite. Therefore, more interactions between nanosheets and polysulfide chains are expected in the structure of unmodified-EG reinforced nanocomposite. Moreover, thermal resistance and degradation kinetics of prepared nanocomposites are studied using thermogravimetric analysis results and degradation activation energy calculations, respectively. The required activation energy for the degradation process of SDBS-EG loaded nanocomposite is about 140 kJ mol?1 lower than the required degradation activation energy of unmodified-nanosheets reinforced nanocomposite. 相似文献
996.
Composite explosives containing aluminum/ammonium perchlorate (Al/AP) are widely used for blasting cut of old warship, blasting droll and decoupled charge of blast underwater. The available complex computer codes and empirical methods cannot usually provide a reliable estimation of detonation velocities of explosives containing Al/AP. This work introduces a reliable method for the desk calculation of detonation velocity. The percent of the reacted Al with detonation products and decomposition of AP, as well as composition of the detonation products, are specified according to the distribution of oxygen atoms between Al, C(s), CO(g) and H2(g). The values of the mean absolute percentage error (MAPE) of the new model are lower than one of the best available methods for CHNO explosives (260 experimental data) and CHNOFCl explosives (50 measured data). For composite explosives, CHNOFClAl and CHNOFClAlAP, the MAPE value of the new model is 3.50, corresponding to 55 experimental data, which is much smaller than the MAPE values of the BKW computer code (8.37) and the comparative empirical model (14.20). 相似文献
997.
An Efficient Method for Chemoselective Reduction of Nitro Compounds Using Bimetallic Fe‐Ni NPs/H3PW12O40.×H2O System 下载免费PDF全文
Soodabeh Rezazadeh Batool Akhlaghinia Elaheh K. Goharshadi Hossein Sarvari 《中国化学会会志》2014,61(10):1108-1114
The selective reduction of nitro compounds by treatment with bimetallic Fe‐Ni nanoparticles (NPs) and tungestophosphoric acid hydrate (H3PW12O40.×H2O) in H2O is reported. The method has been applied to a broad range of nitro compounds with different sensitive functionalities, including halides, carbonyl, hydroxyl, aldehyde, methyl, acetyl, nitrile, and ester substituents with excellent yields. The reaction yielded single product in all cases with very high yield. The simple experimental procedure and easy purification make the protocol advantageous. 相似文献
998.
Efficient and Eco‐friendly Syntheses of 1,5‐Benzothiazepines and 1,5‐Benzodiazepines Catalyzed by [Hmim][NO3] under Mild Conditions 下载免费PDF全文
Hossein Loghmani‐Khouzani Panteha Tamjidi Iraj Mohammadpoor‐Baltork Marzieh Yaeghoobi Noorsaadah Abd. Rahman Ahmad Reza Khosropour Majid Moghadam Shahram Tangestaninejad Valiolah Mirkhani Mohammad Hossein Habibi Ayana Kashima Takayoshi Suzuki 《Journal of heterocyclic chemistry》2014,51(1):138-150
This article presents a synthetic method and reaction mechanism of the 1,5‐benzothiazepines and 1,5‐benzodiazepines derivatives. In this research, 36 thiazepines and diazepines (mostly new) with a new method have been prepared and their structures have been characterized by spectroscopic methods. Crystal structures of a new thiazepine and diazepine (seven‐membered rings) have also been determined and compared with thiazine (six‐membered ring). In this method, N‐methylimidazolium nitrate [Hmim][NO3] has been used as a catalyst that acts as an environmental friendly system. 相似文献
999.
We have explored the feasibility of using a magnetite-doped eggshell membrane as a magnetic solid phase extraction sorbent for the separation of aluminum ion from aqueous solutions. The sorbent was characterized by powder X-ray diffraction, Fourier transform infrared spectroscopy, and scanning electron microscopy. A fast, simple and non-expensive method was then developed for the determination of trace quantities of Al(III) in water and food samples by combining magnetic solid phase extraction with fluorometric quantitation via its highly fluorescent complex with 8-hydroxyquinoline. The effects of pH value, amount of sorbent, sample volume, elution conditions and interfering ions on extraction were optimized. Under optimum conditions, the calibration graph extends from 0.5 to 65.0 μg L?1, the limit of detection is 0.2 μg L?1, and the enrichment factor is 84. The method was validated by the successful analysis of a standard reference material (NIST SRM 1549; nonfat milk powder) and applied to the determination of Al(III) in several waters, black tea, tomato paste and cocoa powder samples. Figure
Synthesis and application of magnetite-doped eggshell membrane for the separation of aluminum(III) ions from aqueous solutions is shown. After extraction for 5 min, the sorbent was gathered under an external magnetic field and the clear supernatant was directly decanted. The enriched analyte was then eluted from the sorbent prior to determination. 相似文献
1000.
Nanofiltration membranes based on blend of polysulfone-g-poly(tert-butylacrylate) copolymer and polysulfone were prepared by phase inversion technique. ATRP grafting of tert-butylacrylate from chloromethylated polysulfone was used for the grafted polymer synthesis. The copolymer was characterized with FTIR, NMR, DSC and TGA. The prepared membranes were characterized in terms of pure water flux, water contact angle, cut off molecular weight, salt rejection and scanning electron microscopy. 相似文献