Jordan University of Science and Technology

About: Jordan University of Science and Technology is a education organization based out in Irbid, Irbid, Jordan. It is known for research contribution in the topics: Population & Health care. The organization has 7582 authors who have published 13166 publications receiving 298158 citations. The organization is also known as: JUST.

X-band EMI shielding mechanisms and shielding effectiveness of high structure carbon black/polypropylene composites

Abstract: The electromagnetic interference (EMI) shielding effectiveness (SE) and EMI shielding mechanisms of high structure carbon black (HS-CB)/polypropylene (PP) composites in the X-band frequency range were studied. Composite plates with three different thicknesses and five different electrical conductivities were studied. The reflection loss and absorption loss of the composites were quantified based on the electromagnetic radiation power balance. The results showed that for HS-CB/PP composites, absorption loss contribution to the overall attenuation is more than the contribution of the reflection loss. The ability of the theoretical model to predict the EMI shielding by reflection and absorption was found to be a function of the shielding plate thickness and conductivity.

Fly ash based geopolymer for heavy metal removal: A case study on copper removal

Abstract: This work aims to evaluate the effectiveness of an amorphous geopolymer, synthesized from waste fly ash, as sorbent material for copper from aqueous solutions. The obtained geopolymer was found to be highly amorphous in structure due to the dissolution of fly ash glass phases. It has much higher removal efficiency compared to the raw fly ash. The removal efficiency was affected by solid/liquid ratio, temperature, reaction time, and Cu2+ initial concentration (C0). The highest Cu2+ removal capacity was obtained at pH 6. The kinetic data were found fit to the pseudo second order kinetic model. Furthermore, it was found that Langmuir model is better than Freundlich model within the temperature range (25–45 °C). The maximum sorption capacity (qm) occurred at 45 °C, reaching a value of 152 mg/g. The sorption process by the obtained geopolymer is endothermic in nature and more favorable at higher temperatures with enthalpy of adsorption of 39.49 kJ/mol. The activation energy of the sorption process at the optimum conditions was found to be 34.9 kJ/mol.

Antibacterial Activity of Jordanian Medicinal Plants

Abstract: The antibacterial activity of ethanol extracts of 15 plant species used in the traditional medicine in Jordan and other Middle East countries were tested. Extracts of certain parts of these plants were tested in vitro against 14 pathogenic bacterial species and strains using the agar diffusion method. Results evaluated as the diameter of inhibition zone of bacterial growth showed that 25 mg/well of 12 plant extracts have antibacterial activity on one or more of the tested bacteria. Three plants exhibited broad spectrum antibacterial activity: Punica granatum L., Quercus infectoria Olive., and Rhus coriaria L. The most susceptible bacteria were Pseudomonas aeruginosa, Bacillus cereus and Streptococcus pyogenes (ATCC 12351), and the most resistant species were Escherichia coli (ATCC 25922 and clinical isolates), Klebsiella pneumoniae, Shigella dysentriae (ATCC 49345), and Yersinia enterocolitica (ATCC 9610). The minimum inhibitory concentrations (MIC) of active extracts ranged from 4‐32 mg/ml while the minimum bactericidal concentrations (MBC) were exerted at higher doses 8‐62 mg/ml.