Atom Probe Tomography (APT) analysis and hardness measurements were used to characterize the early stages of precipitation in an Al-0.51 at%Mg-0.94 at%Si alloy as reported in the accompanying Acta Materialia paper [1]. The changes in microstructure were investigated after single-stage or multi-stage heat treatments including natural ageing at 298 K (NA), pre-ageing at 353 K (PA), and automotive...

Since ancient times, human beings have been trying to protect their skin against the adverse effects of the sun. From the first mineral sunscreens used by Egyptians, to the current more sophisticated ultraviolet (UVA/UVB) organic sunscreens, progress has been made in terms of sun protection and deeper knowledge of skin physiology has been acquired in the process. The solar spectrum is composed ...

the effect of t6 heat treatment on the microstructure and wear behavior of al-332 piston alloy containing 1.2wt% iron was investigated. the results showed that the t6 heat treatment changed the morphology of acicular eutectic si particles to a more spherical form. the heat treatment also reduced the average length and blunted the needle-like ?- phase intermetallics through dissolution and fragm...

The effects of chronic sun exposure on skin are readily apparent when skin not typically exposed to the sun and skin regularly exposed to the sun are compared. While the sun is not the only aetiological factor in the dynamic process of skin ageing, it is the primary exogenous cause among several internal and environmental elements. Thus, photo-ageing, the main focus of this article, is a subset...

The SiC particles (SiCp, mass fraction 30 %) reinforced with the Al-Si-Cu-Mg matrix composite have been prepared using one-way press method, sintering, and hot extrusion. The composite was subjected to solid solution treatment at temperatures of 470 °C, 485 °C, 500 °C, 515 °C, and 530 °C for 4 h. The sample was then subjected to ageing treatment at temperatures of 160 °C and 180 °C during diffe...

apparent rise in the incidence of infertility in females and the trend shifting towards delayed child bearing brought up the concept of ovarian ageing. women in their early thirties show poor ovarian reserve which is an entity named as early ovarian ageing. early ovarian ageing is mostly genetically determined, but acquired modifiable factors like smoking, or ovarian surgery have some roles. in...

ageing is a complex process and a broad spectrum of physical, psychological, and social changes over time. accompanying diseases and disabilities, which can interfere with cancer treatment and recovery, occur in old ages. micrornas (mirnas) are a set of small non-coding rnas, which have considerable roles in post-transcriptional regulation at gene expression level. in this review, we attempted ...

The influence of Zr additions (in the form ZrH2 particles) on microstructure and mechanical properties IN718 Ni-based superalloy manufactured by selective laser melting was explored. Fully dense alloys could be obtained careful selection processing parameters. addition did not modify alloy but introduced a dispersion Zr-rich globular particles approximately 50 nm in diameter which increased str...

In this work the effect of microstructural homogenization and solution annealing prior to ageing on mechanical properties fatigue resistance 18Ni300 maraging steel parts processed by laser powder bed fusion (L-PBF), using two different feedstock powders with N O contents is investigated. The static are not significantly affected selection powders. This ascribed extremely fine size nonmetallic i...