One of the greatest impediments to use polymer-matrix composites is their susceptibility to degradation when exposed to the elevated temperatures and the limited knowledge on the thermal and mechanical properties of these composites at such temperatures. The objective of this study is to evaluate the effects of accelerated heat aging on the tensile properties of the Woven Basalt/Phenolic (WBP) ...

an experiment was conducted to determine the aging mechanism in safflower seed using natural aging treatment (storing seed at room temperature for six years) and accelerated aging ( incubating the seed at 41?c and close to 100% relative humidity for 4 ,8 and 12 days). the results indicated that both natural and accelerated aging reduced germination percentage, seed vigor and activity of catalas...

to evaluate the effects of accelerated aging and cold stress on seed germination and seedling growth indices in five oilseed rape cultivars (hyola330, hyola401, hyola420, syn3 and pr401/15e), an experiment was carried out in a completely randomized design of three replications. results indicated that the cultivars were significantly different in germination percentage, seed vigour, germination ...

objectives : the aim of this study was to assess the effect of artificial accelerated aging (aaa) on color change of direct and indirect fiber-reinforced composite (frc) restorations. materials and methods: direct (z250) and indirect (gradia) composite resins were reinforced with glass (gf) and polyethylene fibers (pf) based on the manufacturers’ instructions. forty samples were fabricated and ...

hutchinson-gilford progeria syndrome (hgps) is a rare premature ageing disorder that is characterized by accelerated degenerative changes of the cutaneous, musculoskeletal and cardiovascular systems. mean age at diagnosis is 2.9 years and generally leading to death at approximately 13 years of age due to myocardial infarction or stroke. orthopedic manifestations of hgps are multiple and shoulde...

This study is aimed at evaluating the performance of tetrakismethylene-3-3,5-di-tert-butyl-4-hydroxyphenyl propionate methane S1010, tris2,4-di-tert-butylphenyl phosphite S1680 and ascorbic acid AA antioxidants in stabilization of hydroxypropyl cellulose HPC. For this purpose, a number of films with weight percent ratios of 0.4 w/w were prepared in a 1 isopropanol solution w/v. Then, the films ...

the old newsprint, as an important grade of waste papers, usually has been produced from chemicalmechanical pulp (cmp). although the effect of paper aging on different properties of recycled pulp has been investigated from long time ago; but, few studies have been observed about the effect of this phenomenon on recycling of cmp paper. in this study, accelerated aging was applied on hardwood cmp...