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81.
Chin Ren Jie Lai Sai Hin Ibrahim Shaliza Wan Jaafar Wan Zurina Elshafie Ahmed Hussein Kamel Ahmed 《Engineering with Computers》2019,35(4):1409-1418
Engineering with Computers - The presence of wall slip in concentrated suspensions affect the rheological measurements such as shear stress, shear rate, and viscosity. The measured shear rate will... 相似文献
82.
Radiochemistry - The uranium removal from radioactive liquid waste using expanded perlite (EP) was studied. The influence of the contact time, solution pH, initial uranium concentration, sorption... 相似文献
83.
A. E. Saba A. E. El Sherif E. M. Elsayed 《JOM Journal of the Minerals, Metals and Materials Society》2007,59(10):53-57
Copper is usually present in concentrations less than 5 g/L−1 in dilute waste solutions. The low concentrations make these solutions unsuitable for the electro-flow owinning processes
via conventional electrolysis cells. Unconventional, two-and three-dimensional electrode cells with relatively large cathodic
area are essential for such treatment. Different types of cells are mentioned in the literature. Among these cells, the two-dimensional
Swiss-roll cell (SR) is considered in this study. The effects of cathodic current densities, initial copper concentrations,
free sulfuric acid concentration, the presence of iron and zinc cations, and the rate of flow of the solution on both the
cathodic current efficiency and power consumption were studied. Copper was removed from synthetic and industrial mixtures
of Cu/Fe/Zn sulfate solutions to less than 5 ppm with power consumptions of 10.326 kWh/kg−1 and 8.61 kWh/kg−1, respectively. The correlation between the SR cell and packed-column cell on such treatment was also considered. 相似文献
84.
Lisa Biasetto Rachele Bertolini Hamada Elsayed Andrea Ghiotti Stefania Bruschi 《Ceramics International》2019,45(5):5941-5951
Rods of commercially pure titanium were machined using standard oil-based emulsion and cryogenic cooling, and were then coated with sphene (CaTiSiO5) bioceramic by spray coating using an automatic airbrush. The sphene bioceramic was synthesized in-situ starting from a suspension of polysiloxane that used as SiO2 precursor, CaCO3 and TiO2 nanoparticles. The suspension was deposited on the machined substrates, which were heat treated up to 950?°C in order to promote the formation of sphene ceramic. The produced coated prototypes were characterized to evaluate the effect of the machining conditions on surface roughness and microstructure of the substrate, and thereby their effect on coating adhesion. Nanoindentation tests were employed to determine the hardness and elastic modulus of the coating through its thickness. Results showed that the reduced amount of defects on the surface of the cryo-machined substrates, contributed to increase the hardness, elastic modulus and adhesion strength of the coating-substrate interfaces compared to standard machined samples, therefore improving adhesion of the coating to the underlying substrate. 相似文献
85.
86.
Magdy W. Sabaa Nadia A. Mohamed Riham R. Mohamed Soliman M. Abd El Latif 《Polymer Bulletin》2011,67(4):693-707
A novel super absorbent polymer was prepared by graft copolymerization of 4-vinyl pyridine (4VP) onto the chains of carboxymethyl
chitosan in aqueous solution using potassium persulphate (KPS) as initiator. The effect of monomer and initiator concentration,
reaction temperature, and time on the grafting yield has been investigated. The maximum grafting yield was achieved at [KPS] = 4 × 10−2 mol/L, [M] = 2.5 mol/L at reaction temperature = 60 °C within reaction time = 3 h. The molecular structure of the graft copolymer
was confirmed by FTIR, surface morphology before and after the polymerization was examined by SEM. Different analyses were
done for the graft copolymer such as X-ray diffraction, solubility tests, and thermal analysis. Different applications were
done on the graft copolymer such as swell ability in different pH solutions, dye, and metal uptake. 相似文献
87.
Synthesis,Characterization and Surface Activity of New Eco-friendly Schiff Bases Vanillin Derived Cationic Surfactants 总被引:1,自引:0,他引:1
Nabel A. Negm Nadia G. Kandile Mohamad A. Mohamad 《Journal of surfactants and detergents》2011,14(3):325-331
Three eco-friendly cationic surface active agents were synthesized from the chemical modification of vanillin. The chemical
structures of these surfactants were confirmed using elemental analysis, IR and NMR spectra. The surface activity measurements
showed their high tendency towards adsorption and micellization and their good surface tension reduction, low interfacial
tension. The emulsion stability measurements showed acceptable efficiency as emulsifying agents for short term emulsions.
The biodegradability tests revealed that these compounds are eco-friendly and had completely degraded in 30 days. 相似文献
88.
Muhammad J. Khan Abdulhadi A. Al‐Juhani Anwar Ul‐Hamid Reyad Shawabkeh Ibnelwaleed A. Hussein 《应用聚合物科学杂志》2011,122(4):2486-2496
In this study, the effect of oil fly ash (OFA), a by‐product of oil fuel power plants, on the rheological and morphological behavior of low‐density polyethylene (LDPE) is investigated. As received and acid‐functionalized OFA (COOH‐OFA) are used to examine the effect of surface modification of OFA on polymer–filler composites. LDPE/OFA composites were prepared by melt mixing with filler loading in the range 1–10 wt %. The results are compared with pure LDPE. The effect of polyethylene‐grafted‐maleic anhydride (PE‐g‐MA) as a compatibilizer was also studied. Both viscous and elastic properties of composites increased with OFA loading especially at low frequency. The surface modification of OFA has influenced the properties of OFA. As‐received OFA showed some agglomeration at high loading that resulted in two‐phase system as described by scanning electron microscopy (SEM) and Cole–Cole plot. Field emission‐SEM (FE‐SEM) images showed improvement in the dispersion of COOH‐LDPE/OFA composites. In addition, the surface modification reduced the size of agglomeration. In general, the COOH modification of OFA improved both the dispersion and rheological properties of OFA. With chemical modification, the concentration of the filler can be increased to 10% without compromising the properties of the composites. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011. 相似文献
89.
Mahmoud A. Hussein Reda M. El-Shishtawy Abdullah Y. Obaid Mohamed Abdel Salam 《Polymer-Plastics Technology and Engineering》2018,57(11):1150-1163
The present work is aimed to fabricate a new set of composite materials containing conducting poly(azomethine-ether) reinforced with single-walled carbon nanotubes in the form of single-walled carbon nanotube/poly(azomethine-ether)1–5 for excellent enhanced thermal as well as conducting behavior of poly(azomethine-ether). Single-walled carbon nanotubes of variable loading have been embedded into conducting poly(azomethine-ether) using in situ polymerization technique. Before attempting the polymerization, 1,3-thiazole established poly(azomethine-ether) and its conformable monomers have been prepared and their chemical structures have been correlated by spectral analyses. Furthermore, ηinh and Mw values for poly(azomethine-ether) were found 0.89?dL?g?1 and 39723.6, respectively. The fabricated single-walled carbon nanotube/poly(azomethine-ether)1–5 composites were specified and characterized by wide-angle X-ray diffraction patterns, Fourier transform infrared spectroscopy, thermal behavior, scanning electron microscopy, and transmission electron microscopy characterization techniques. A perfect indicative response for this composite material was estimated by Fourier transform infrared spectra and X-ray diffraction as well. Both techniques displayed all intensive characteristic peaks regarding single-walled carbon nanotubes and poly(azomethine-ether) in the spectra or diffraction pattern for single-walled carbon nanotube/poly(azomethine-ether)1–5. The role of single-walled carbon nanotubes on the performance of poly(azomethine-ether) was considerably examined. Single-walled carbon nanotube/poly(azomethine-ether)1–5 showed relatively higher thermal stability. Single-walled carbon nanotube/poly(azomethine-ether)1 displayed the lowest final composite degradation temperature value (552°C), whereas single-walled carbon nanotube/poly(azomethine-ether)5 displayed the highest value (621°C). T10 and T25 values showed a gradual temperature increased while single-walled carbon nanotubes increased. Single-walled carbon nanotube/poly(azomethine-ether)1 showed the lowest thermal stability and single-walled carbon nanotube/poly(azomethine-ether)5 showed the highest thermal stability between all fabricated products. Furthermore, transmission electron microscopy images showed a prominent increase in single-walled carbon nanotubes diameters (40–60?nm). The conductivity values were significantly increased while single-walled carbon nanotubes content was increased and reached to the semiconductors. ε′ values were also increased in both single-walled carbon nanotube/poly(azomethine-ether)4,5 which have higher single-walled carbon nanotubes content. 相似文献
90.