Taymour Hamdallah

Dr. Taymour Hamdallah


Research Focus & Metrics

Academic Career Length

21Years (2006-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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14 February 2022 in Optical Materials
Verified
Journal Article
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SKSyed Khasim
Syed Khasim
APApsar Pasha
Apsar Pasha
MLMohana Lakshmi
Mohana Lakshmi
PCPanneerselvam Chellasamy
Panneerselvam Chellasamy
MKMurugan Kadarkarai
Murugan Kadarkarai
SAS. Alfadhli
S. Alfadhli

1 January 2015 in Journal of Spectroscopy
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Journal Article
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THTaymour Hamdallah
Taymour Hamdallah
THTaha A. Hanafy
Taha A. Hanafy
ABAshraf E. Bekheet
Ashraf E. Bekheet
Polyvinyl alcohol (PVA) films doped with erbium chloride (ErCl3) have been prepared by casting from their aqueous solutions. The structure of the doped samples as well as the interactions between the host PVA and Er+3was investigated using FTIR spectroscopy. The optical measurement was recorded at room temperature in the range from 200 nm to 2000 nm. FTIR measurements revealed that Er+3forms complex configuration within the PVA structure. PVA doped with 9 wt% of ErCl3exhibits energy gap and refractive index of 5.1 eV and 1.72, respectively. The effect of the doping increment of ErCl3on the optical parameters has been discussed.

29 November 2016 in Phase Transitions
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Journal Article
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SNSherif S. Nafee
Sherif S. Nafee
THTaymour Hamdallah
Taymour Hamdallah
SSSalem A. Shaheen
Salem A. Shaheen
There are various chemical and physical changes caused when polymers are exposed to a source of radiation. In the present work, four films of polyvinyl alcohol (PVA) doped with 2, 4, 6 and 8 wt% of gadolinium chloride (GdCl3) have been irradiated by low-dose fast neutrons using Am-241/Be-9. The structural properties of the synthesized films have been investigated pre- and post-irradiation on the basis of Fourier transform infrared technique. The optical properties of the PVA–GdCl3 films have been investigated for doses up to 1.2 KGy. The energy gap of the synthesized films showed a neutron dose dependence and was decreased by 0.81 eV after exposing to 1.2 kGy. At a wavelength of 1000 nm, the refractive index of the PVA doped with 8 wt% GdCl3 has been increased by nearly 16%. The results suggested the possible use of PVA--GdCl3 as a dosimeter for the neutron beams.

15 December 2023 in Scientific Reports
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MAMarwah Ahmed Alsharif
Marwah Ahmed Alsharif
AAAishah Alatawi
Aishah Alatawi
THTaymour Hamdallah
Taymour Hamdallah
SAS. Alfadhli
S. Alfadhli
ADA. A. A. Darwish
A. A. A. Darwish
The present analysis aims to use existing resources to lower the cost of electrodes and reduce environmental pollution by utilizing waste materials like green algae. In the present research, the hydrothermal carbonization technique was utilized to synthesize a nano sized CuO mixed with activated biochar (CuO@BC) extracted from red sea algae (Chlorophyta). The CuO@BC sample was extensively examined using several advanced physical techniques, such as UV/Visible spectroscopy, FTIR, XED, HRTEM, SEM, EDX, BET, and TGA. The HRTEM indicated that the size of the particles is 32 nm with a larger surface area and without aggregations. The BET analysis of CuO@BC indicates that the material contains pores of a relatively large size and with a pore diameter of about 42.56 A°. The electrochemical analysis of CuO@BC modified glassy carbon electrode CuO@BC/GCE has been investigated using CV, GCD, and EIS techniques. This CuO@BC/GCE shows excellent electrochemical features that are significant for energy storage applications. The CuO@BC/GCE showed a specific capacitance of approximately 353 Fg−1 which is higher compared to individual materials. Overall, the research outcomes suggest that the CuO@BC/GCE shows potential for use in high-performance supercapacitors as energy storage systems that are eco-friendly and sustainable.

19 April 2019 in Phase Transitions
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Journal Article
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THTaymour Hamdallah
Taymour Hamdallah
THTaha A. Hanafy
Taha A. Hanafy
SSSeleim M. Seleim
Seleim M. Seleim
Rare-earth elements (REEs) as Tm+3, Er+3, Yb+3 and Nd+3 have a significant optical photon emission. Therefore, Films of PMMA doped with 5 wt.% of NdCl3, TmCl3, ErCl3 or YbCl3 were prepared using the casting technique. FTIR of the prepared films has been studied. The optical and dispersion behavior of all doped samples have been investigated. The reflectance (R) and the transmittance (T) were measured in the wavelength range of 200–2500 nm. FTIR of all PMMA reveals that, REEs addition to PMMA samples creates new transmission peaks C=O groups and a decrease in the intensity of the absorption band of C–O groups has been obtained. The results showed the dependency of the refractive index and energy gap on the REE electronic transitions nature. The obtained results suggest strongly the applicability of these PMMA derivatives in improving the performance of the polymer optical fiber (POF).

18 November 2024 in Processes
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Journal Article
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NDNourhane A. Darwich
Nourhane A. Darwich
MMMalak Mezher
Malak Mezher
AAAlaa M. Abdallah
Alaa M. Abdallah
Ahmed Fikry El-sayedAhmed Fikry El-sayed
Ahmed Fikry El-sayed
RHRana El Hajj
Rana El Hajj
Mahmoud Ibrahim KahlilMahmoud Ibrahim Kahlil
Mahmoud Ibrahim Kahlil
The current study focused on the synthesis of doped silver nanoparticles (doped AgNPs) with yttrium (Y), gadolinium (Gd), and chromium (Cr) from pine needle leaf extract (PNLE). X-ray diffraction (XRD) was performed to assess the phase formation, detecting 61.83% from Ag and 38.17% for secondary phases of AgCl, AgO, Y, Cr-, and Gd phases. The size and shape of the NPs were determined by transmission electron microscopy (TEM), showing a spherical shape with an average particle size of 26.43 nm. X-ray photoelectron spectroscopy (XPS) detected the oxidation state of the presented elements. The scanning electron microscope (SEM) and the energy-dispersive X-ray analysis (EDX) determined the morphology and elemental composition of the NPs, respectively. Fourier transform infrared spectroscopy (FTIR) determined the different functional groups indicating the presence of Ag, Y, Gd, Cr, and other groups. Photoluminescence (PL) spectroscopy showed the optical properties of the NPs. A vibrating sample magnetometer (VSM) revealed the ferromagnetic behavior of the doped AgNPs. The antibacterial activity of the doped AgNPs was tested against six uro-pathogenic bacteria (Staphylococcus aureus, Staphylococcus haemolyticus, Enterococcus faecalis, Escherichia coli, Klebsiella pneumonia, and Pseudomonas aeruginosa) using the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) microdilution assays, agar well diffusion assay, time–kill test, and antibiofilm screening assays, revealing significant activity, with MICs ranging between 0.0625 and 0.5 mg/mL and antibiofilm activity between 40 and 85%. The antioxidant activity was determined by the 1,1, diphenyl 1-2 picrylhydrazyl (DPPH) radical scavenging assay with a potential of 61.3%. The docking studies showed that the doped AgNPs had the potential to predict the inhibition of crucial enzymes such as penicillin-binding proteins, LasR-binding proteins, carbapenemase, DNA gyrase, and dihydropteroate synthase. The results suggest that the doped AgNPs can be applied in different medical domains.