Most varicose and spider veins appear in the legs due to the pressure of body weight, force of gravity, and task of carrying blood from the bottom of the body up to the heart. Compared with other veins in the body, leg veins have the toughest job of carrying blood back to the heart. They endure the most pressure.
Curing a thermosetting resin transforms it into a plastic, or elastomer by crosslinking or chain extension through the formation of covalent bonds between individual chains of the polymer. Crosslink density varies depending on the monomer or prepolymer mix, and the mechanism of crosslinking:
Curing plays an important role on strength development and durability of concrete. Curing takes place immediately after concrete placing and finishing, and involves maintenance of desired moisture and temperature conditions, both at depth and near the surface, for extended periods of time.he curing period for cold weather concrete is longer than the standard period due to reduced rate of strength gain. Compressive strength of concrete cured and maintained at 50 degrees Fahrenheit is expected to gain strength half as quickly as concrete cured at 73 degrees Fahrenheit.