السجلات المعروضة 301 -- 320 من 3563

    • Mechanical and thermal properties of gamma-ray irradiated polyethylene blends 

      Mariam, Al-Ali; Madi, N.K; Al Thani, Nora J.; El-Muraikhi, M.; Turos, A. ( Elsevier , 2003 , Conference Paper)
      In this work, the results obtained by gamma-ray irradiation of polyethylene (PE) blends are presented. The blends were produced by injection molding at 220°C with different compositional ratios, i.e. 100/0, 15/85, 25/75, ...
    • Compositional transformations in ion implanted polymers 

      A.M., Abdul-Kader; Turos, A.; Grambole, D.; Jagielski, J.; Piątkowska, A.; ... more authors ( Elsevier , 2005 , Conference Paper)
      Changes of surface layer composition produced by ion bombardment of polyethylene and polypropylene samples were studied. These materials are under consideration for load bearing surfaces in biological and technical ...
    • Study on ferroelastic characteristics of gamma irradiated lithium potassium sulfate crystal 

      N.K, Madi; Kassem, M.E; El-Muraikhi, M; El-Khatib, A.M ( Elsevier , 1999 , Article)
      A detailed study of the optical absorption vs. γ-irradiation dose for lithium potassium sulfate crystal, LiKSO4 cut out perpendicular to x, y and z directions is presented. The optical density was measured within the ...
    • Temperature and electric field effects on the dielectric dispersion of modified polyvinyl chloride 

      M.E., Bassiouni; Al-Shamy, F.; Madi, N.K.; Kassem, M.E. ( Elsevier , 2003 , Article)
      The effect of electric field on the dielectric dispersion of modified polyvinyl chloride (PVC) has been investigated. The applied direct current (DC) field strength was ranging from 0 to 104 V cm−1. The complex permitivity ...
    • Surface layer modification of ion bombarded HDPE 

      D., Bielinski; Lipinski, P.; Slusarski, L.; Grams, J.; Paryjczak, T.; ... more authors ( Elsevier , 2004 , Article)
      Press-moulded, high density polyethylene (HDPE) samples were subjected to ion bombardment and effects of the modification studied. He+ ions of energy 100 keV or Ar+ ions of energy 130 keV were applied in the range of dose ...
    • The effects of ion bombardment of ultra-high molecular weight polyethylene 

      A., Turos; Abdul-Kader, A.M.; Grambole, D.; Jagielski, J.; Piątkowska, A.; ... more authors ( Elsevier , 2006 , Article)
      Ion bombardment is a suitable tool to improve tribological properties of polymers. In this study UHMWPE samples were bombarded with 130keV He ions to the fluences ranging from 1×1014 to 2×1016cm−2. RBS and NRA techniques ...
    • Effectiveness of two and three doses of COVID-19 mRNA vaccines against infection, symptoms, and severity in the pre-omicron era: A time-dependent gradient 

      Layan, Sukik; Chemaitelly, Hiam; Ayoub, Houssein H.; Coyle, Peter; Tang, Patrick; ... more authors ( Elsevier , 2024 , Article)
      BackgroundVaccines were developed and deployed to combat severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. This study aimed to characterize patterns in the protection provided by the BNT162b2 and ...
    • Eutrophication in the coastal waters of Alexandria following the increase in phosphorus load 

      Abdel-Moati, M. A.R. ( Parlar Scientific Publications , 1996 , Article)
      Samples from the coastal waters of Alexandria during 1991-1993 indicate a remarkable increase in the phosphorus load from 870 to 1140 kg y-1 compared to 567 kg y-1 in 1986 raising the average phosphorus from 1.01 to 1.47 ...
    • Dissolved copper, cadmium and lead in the coastal waters of Qatar, Arabian Gulf 

      Abdel-Moati, M. A.R.; Kureishy, T. W. ( National Institute of Science Communication and Information Resources (NISCAIR) , 1997 , Article)
      The concentrations of Cu, Pb and Cd have been determined in the exclusive economic zone of Qatar, Arabian Gulf during December 1993. Cathodic stripping voltammetry (CSV) was used both before and after UV destruction of ...
    • A Comprehensive Machine and Deep Learning Approach for Aerosol Optical Depth Forecasting: New Evidence from the Arabian Peninsula 

      Alban, Ahmad Qadeib; Abulibdeh, Ammar; Charfeddine, Lanouar; Abulibdeh, Rawan; Abuelgasim, Abdelgadir ( Springer Nature , 2024 , Article)
      Accurate forecasting of environmental pollution indicators holds significant importance in diverse fields, including climate modeling, environmental monitoring, and public health. In this study, we investigate a wide range ...
    • Addressing bias in the definition of SARS-CoV-2 reinfection: implications for underestimation 

      Chemaitelly, Hiam; Ayoub, Houssein H.; Tang, Patrick; Yassine, Hadi M.; Al Thani, Asmaa A.; ... more authors ( Frontiers Media , 2024 , Article)
      Introduction: Reinfections are increasingly becoming a feature in the epidemiology of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. However, accurately defining reinfection poses methodological ...
    • Antibody-dependent enhancement (ADE) of SARS-CoV-2 in patients exposed to MERS-CoV and SARS-CoV-2 antigens 

      Thomas, Swapna; Smatti, Maria K.; Alsulaiti, Haya; Zedan, Hadeel T.; Eid, Ali H.; ... more authors ( Wiley , 2024 , Article)
      This study evaluated the potential for antibody-dependent enhancement (ADE) in serum samples from patients exposed to Middle East respiratory syndrome coronavirus (MERS-CoV). Furthermore, we evaluated the effect of severe ...
    • Prevalence of hepatitis B and C viruses among migrant workers in Qatar. 

      Nasrallah, Gheyath K; Chemaitelly, Hiam; Ismail, Ahmed I A; Nizamuddin, Parveen B; Al-Sadeq, Duaa W; ... more authors ( Springer Nature , 2024 , Article)
      Limited data exist on viral hepatitis among migrant populations. This study investigated the prevalence of current hepatitis B virus (HBV) infection and lifetime hepatitis C virus (HCV) infection among Qatar's migrant craft ...
    • Enhancement of photovoltaic module performance by thermal management using shape-stabilized PCM composites 

      Safna, Nishad; Ahmad, Zubair; Krupa, Igor ( Elsevier , 2024 , Article)
      Thermal management of photovoltaic (PV) panels is crucial due to the deterioration of their electrical efficiency at elevated operating temperatures. Therefore, thermal protection of PV against overheating is highly required. ...
    • Ether, sulfide and sulfone derivatives of cinnamaldehyde: Insights into synthesis, structural elucidation and solvatochromism 

      Jawaher S., Al-Marri; Shraim, Amjad M.; Salih, Kifah S.M. ( Elsevier , 2024 , Article)
      Symmetric ether, sulfide and sulfone derivatives based on Schiff base functionalized group (3a-c) were synthesized via classical condensation of 4,4′-diaminodiphenyl precursors (1a-c) and cinnamaldehyde (2) in methanol at ...
    • Environmental Drivers of Habitat Use by Hawksbill Turtles (Eretmochelys imbricata) in the Arabian Gulf (Qatar) 

      Marshall, Christopher D.; Cullen, Joshua A.; Al-Ansi, Mehsin; Hamza, Shafeeq; Abdel-Moati, Mohamed A.R. ( Frontiers Media SA , 2020 , Article)
      Understanding the environmental drivers of movement patterns are critical to the protection, management and recovery of endangered species. The Arabian Gulf is considered to be the hottest marine system in the world and ...
    • Pinctada radiata (pearl oyster): A bioindicator for metal pollution monitoring in the Qatari waters (Arabian Gulf) 

      Al-Madfa, H.; Abdel-Moati, M. A.R.; Al-Gimaly, F. H. ( Springer Nature , 1998 , Article)
      Bivalves are extensively used in monitoring programmes in the marine environment due to their ability to concentrate pollutants to several orders of magnitude above ambient levels in sea water. Commonly, the levels of ...
    • Beach tar contamination on the Qatari coastline of the Gulf 

      H., Al-Madfa; Abdel-Moati, M.A.R.; Al-Naama, A. ( Elsevier , 1999 , Article)
      Beach tar concentrations were measured along the Qatari coastlines. Tar concentrations, collected from 11 locations, varied in space and time with values ranging between 2 and 1132 g m−1 (average 290 g m−1) of beach front. ...
    • The effect of graphene on the activation energy of grain growth for the nanocrystalline thermoelectric n-type Bi2Te2.7Se0.3 

      El-Makaty, Farah M.; Pothuvattil, Nandagopal S.; Hamouda, Abdelmagid; Youssef, Khaled M. ( Springer Nature , 2022 , Article)
      Even though bismuth telluride is frequently produced by mechanical alloying for thermoelectric materials, no data has been published addressing the thermal behavior and activation energy of the milled n-type Bi2Te2.7Se0.3 ...
    • Acute effect of toe cap choice on toe deviation angle and perceived pain in female professional ballet dancers 

      Salzano, Annamaria; Camuso, Fabiana; Sepe, Mario; Sellami, Maha; Ardigò, Luca P.; ... more authors ( Hindawi Limited , 2019 , Article)
      Several classical dance complex movements, such as pointe, require body weight to be supported properly to avoid risk of foot injury. Regarding the choice of toe cap for pointe shoes, it is unclear which type can better ...