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Positron annihilation and ion beam analysis of ion-bombardment-induced hydrogen release and oxidation of ultra high molecular weight polyethylene
(
Elsevier
, 2007 , Article)
Ultra high molecular weight polyethylene was bombarded with He+ and Ar+ ions to fluences ranging from 1013 to 2×1016 ions/cm2. Rutherford backscattering and nuclear reaction analysis were applied to study mechanism of ...
The effect of gamma irradiation and shelf aging in air on the oxidation of ultra-high molecular weight polyethylene
(
Elsevier
, 2006 , Article)
This study has investigated the effect of shelf aging, for up to one year in air, on the properties of gamma-irradiated ultra-high molecular weight polyethylene (UHMWPE). A variety of techniques were used to characterize ...
Radon concentration determination in some dwellings of Doha city of Qatar
(
Elsevier
, 1997 , Article)
Yearly average radon concentrations have not been reported yet in Qatar. Only few measurements on indoor radon concentrations have been conducted during the autumn season in 1992. To complete these measurements a determination ...
Thermalization times of positrons in molecular gases
(2000 , Article)
The time that a particle takes to reach thermal equilibrium in gas is a gross measure of the efficiency with which such particle can exchange its kinetic energy with the medium. The time taken for positrons to reach thermal ...
Positron annihilation lifetime study of pure and treated polyvinyl chloride
(
scientific.net
, 1997 , Article)
Positron annihilation lifetime technique (PAL) has been applied to investigate the behavior of the free volume in pure and doped polyvinyl chloride (PVC) as a function of Pb concentration and temperature. It is noticed ...
Three-body effects in the annihilation of positrons on molecules
(
APS
, 2002 , Article)
The three body effects in the annihilation of positrons on molecules were discussed. The positron annihilation in ethylene gas at room temperature and at densities below one amagat, showed that the mean free positron ...
Assessing spatial confounding in cancer disease mapping using R
(
Blackwell Publishing Ltd
, 2020 , Article)
Background: Exploring spatial patterns in the context of cancer disease mapping (DM) is a decisive approach to bring evidence of geographical tendencies in assessing disease status and progression. However, this framework ...
On the Investigation of Monthly River Flow Generation Complexity Using the Applicability of Machine Learning Models
(
Hindawi Limited
, 2021 , Article)
Streamflow is associated with several sources on nonstationaries and hence developing machine learning (ML) models is always the motive to provide a reliable methodology to understand the actual mechanism of streamflow. ...
Causes of Undergraduate Students' Underachievement in a Gulf Cooperation Council Country (GCC) University
(
SAGE Publications Inc.
, 2022 , Article)
UNESCO reports enrollment in higher education in the Arab and Gulf Cooperation Council region doubled from 5.1 million in 2000 to 10.7 million in 2015. Despite significant budgets and the world's lowest teacher-to-student ...
Estimation of health-related quality of life in the presence of missing Values in EQ-5D
(
Hindawi Limited
, 2021 , Article)
One of the notes worthy problems in analysis of clinical and observational studies is missing data and nonresponse from patients. Turning a blind eye to the missing behavior may provide biased results with overestimated ...