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131.
Ayman M. Atta Hamad A. Al-Lohedan Abdelrahman O. Ezzat Zuheir A. Issa Ahmad B. Oumi 《Journal of Polymer Research》2016,23(4):69
In this work, we aimed to develop a feasible method for in situ preparation of a magnetite ionic polymer nanocomposite at room temperature. For this purpose, acrylonitrile (AN) and 2-acrylamido-2-methylpropane sulfonic acid (AMPS) monomers were copolymerized and crosslinked using different monomer mol ratios in the presence of N,N-methylenebisacrylamide (MBA) as crosslinker to produce ionic crosslinked polymers P(AN-co-AMPS. The nitrile groups were converted to amine amidoxime by reacting with hydroxylamine to increase the adsorption characteristics of the ionic polymers. The produced polymers were swelled in iron cations produced from the reaction of ferric chloride and potassium iodide, followed by reaction with an ammonium hydroxide solution to produce magnetite nano-polymer composites. We performed FT-IR and XRD analysis to determine the chemical and crystalline structures, and assessed the morphologies and magnetite content using SEM, TEM and TGA analyses. We investigated the adsorption capacity and mechanism of the prepared magnetite nano-composites as adsorbents for methylene blue, Co2+ and Ni2+ cations from water. 相似文献
132.
Zalooli Ahmad Khamehchiyan Mashalah Nikudel Mohammad Reza 《Bulletin of Engineering Geology and the Environment》2019,78(3):1683-1695
Bulletin of Engineering Geology and the Environment - Durability is the most important characteristic of stones in sustainable architecture. Salt crystallization has been known to damage porous... 相似文献
133.
134.
Air pollution is a major health problem in developing countries and has adverse effects on human health and the environment. Non-thermal plasma is an effective air pollution treatment technology. In this research, the performance of a dielectric barrier discharge (DBD) plasma reactor packed with glass and ceramic pellets was evaluated in the removal of SO2 as a major air pollutant from air in ambient temperature. The response surface methodology was used to evaluate the effect of three key parameters (concentration of gas, gas flow rate, and voltage) as well as their simultaneous effects and interactions on the SO2 removal process. Reduced cubic models were derived to predict the SO2 removal efficiency (RE) and energy yield (EY). Analysis of variance results showed that the packed-bed reactors (PBRs) studied were more energy efficient and had a high SO2 RE which was at least four times more than that of the non-packed reactor. Moreover, the results showed that the performance of ceramic pellets was better than that of glass pellets in PBRs. This may be due to the porous surface of ceramic pellets which allows the formation of microdischarges in the fine cavities of a porous surface when placed in a plasma discharge zone. The maximum SO2 RE and EY were obtained at 94% and 0.81 g kWh−1, respectively under the optimal conditions of a concentration of gas of 750 ppm, a gas flow rate of 2 l min−1, and a voltage of 18 kV, which were achieved by the DBD plasma packed with ceramic pellets. Finally, the results of the model's predictions and the experiments showed good agreement. 相似文献
135.
Mirzaei Ahmad Navarchian Amir H. Tangestaninejad Shahram 《Iranian Polymer Journal》2020,29(6):479-491
Iranian Polymer Journal - Gas separation membranes with enhanced performance were developed by the introduction of nanosized palladium particles. In this study, gas separation performance of... 相似文献
136.
137.
Hani Hafeeza Halim Elfy Williams Dee Mohd Sabri Pak Dek Azizah Abdul Hamid Ahmad Ngalim Nazamid Saari 《International Journal of Food Properties》2018,21(1):2378-2389
The present work aimed to compare the main ergogenic attributes of two commercialized stages (young and mature) of coconut water (CW) obtained from four coconut varieties. The changes of electrolytes and sugars in CW upon maturation were quantified by inductively coupled plasma mass spectrophotometer and high-performance liquid chromatography, respectively. Based on the electrolyte profiling, potassium yielded the highest amount (ranging from 237.41 to 361.20 mg/100 mL) followed by sodium, magnesium, calcium, iron, manganese, copper, selenium, and zinc across all the maturity stages tested. For sugars, there were lower amounts of fructose and glucose, but a higher amount of sucrose with the maturation of the fruits. In conclusion, the amount of beneficial nutrients in the form of sugars and minerals was higher than that of young CW, and the ergogenic attributes of mature CW especially from MATAG variety (M-MATAG) were the best to be exploited further in the development of natural energy drinks. 相似文献
138.
Abdul Latif Ahmad Choe Peng Leo Syamsul Rizal Abd. Shukor 《Journal of Porous Materials》2009,16(1):33-40
Porous γ-alumina with well arranged secondary mesopores has been contrived using nanosized templating units. The pore size
of templated mesopores is precisely controlled as the pore shrinkage is insignificant. The primary pore diameter is ca. 4 nm
and the secondary pore diameter is ca. 50 nm. The porous material was characterized using N2 adsorption/desorption, TEM, XRD and FT-IR. γ-alumina with bimodal pore size distribution shows improved intra-particle diffusion
compared to γ-alumina with unimodal pore size distribution in a simple dye adsorption test. γ-alumina with different porous
structures were then impregnated with vanadium oxide for catalytic effect comparison. It was perceived that secondary pores
improve the styrene oxidation rate after the conversion of styrene reaches 30%. 相似文献
139.
Ahmad Rahimirad M. Emami M. Ghoranneviss A. Salar Elahi 《Journal of Fusion Energy》2009,28(4):420-426
We have expressed two different methods to determine the plasma positions in the IR-T1 tokamak. An array of magnetic probes
are placed polidally outside the chamber surface and their signals are plugged in the displacement equation and horizontal
displacement of plasma column is obtained. The results of this measurement are compared with the experimental data obtained
from sensors of multipole moment. It was detected a fluctuation in plasma displacement obtained with discrete magnetic coils,
so the method of multiple moments is better than the discrete magnetic coils for the determination plasma displacement that
used for feed back control. 相似文献
140.
The fast and maximum thermal neutron fluxes from the DD-109 neutron generator at the University of Sharjah were experimentally measured by the activation technique using different neutron reactions. The thermal and fast neutron fluxes were found to be 2.960 × 10~6 and6.186 × 10~7 n/cm~2 s, respectively. This was done to verify the modeling results for the optimum moderator thickness needed to maximize the thermal neutron flux. The optimum moderator thickness was found to be between 3.5 and4 cm. The present data were compared with the detailed MCNP model-based calculation performed in earlier work to simulate the generator. 相似文献