The thermogravimetric analysis (TGA) and the differential thermal analysis (DTA) were applied to investigations of aging processes in some electroinsulating polymeric materials (glass reinforced epoxy resin, NBR ( two sorts), styrenated unsatured polyester resin, hydrogenated NBR (T80), polychloroprene rubber , EPR) and to the measurement of aging reaction rates. It is shown that thermal analys...

aging coefficient (ac) or aged-child ratio or age composition; takes into account the numbers and areas at both ends of the age distribution simultaneously. ac is the total number of individuals aged 65 years and more, divided by the total number of individuals aged 14 years, multiplied by 100. herein, age composition in iranian popu1ations, according to different provinces, place of residence ...

background osteoarthritis (oa) is a multifactorial, disabling and degenerative disease that worsens with age and affects patient’s health-related quality of life (hrqol). objectives the current study aimed to assess if age and comorbidities have an influence on knee oa and knee replacement outcome before and after the surgery. methods a quasi-experimental intervention study was conducted on a s...

results men had significantly higher quality of life in all dimensions and components compared to women (p < 0.01), while there was no sex difference in the hei scores. the hei scores were positively correlated with the qol total score (p < 0.05) and its physical health dimensions (p < 0.01); the significant correlation was eliminated after adjusting the data for age and gender. the hei and qol...

Purpose: The purpose of the current study was to examine the effect of accelerated aging on color stability of the In-Ceram and Cergogold ceramic materials. Materials and Methods: Ceramic samples with 1.0 mm in diameter and 1.5 mm in thickness were prepared in three commonly used shades. CIE Lab readings were recorded with a spectrophotometer prior to experiments and after 100-hour accelerated ...

An adsorption-desorption (or parking-lot) model can reproduce qualitatively the densification kinetics and other features of a weakly vibrated granular material. Here we study the the two-time correlation and response functions of the model and demonstrate that their behavior is consistent with recently observed memory effects in granular materials. Although the densification kinetics and hyste...