Seismic wave Seismic wave Seismic waves are waves of energy that travel through the Earth's layers, and are a result of earthquakes, volcanic eruptions, magma movement, large landslides and large man-made explosions that give out low-frequency acoustic energy. Many other natural and anthropogenic sources create low-amplitude waves commonly referred to as ambient vibrations. Seismic waves are studied by geophysicists called seismologists. Seismic wave fields are recorded by a seismometer, hydrophone (in water), or accelerometer. The propagation velocity of the waves depends on density and elasticity of the medium.Velocity tends to increase with depth and ranges from approximately 2 to 8 km/s in
Antioxidant effect of polyphenols and natural phenols in the prevention or treatment of skin aging in humans are absent. Experiments on linoleic acid subjected to 2,2′-azobis (2-amidinopropane) dihydrochloride-induced oxidation with different combinations of phenolics show that binary mixtures can lead to either a synergetic effect or to an antagonistic effect. Antioxidant levels of purified anthocyanin extracts were much higher than expected from anthocyanin content indicating synergistic effect of anthocyanin mixtures. Antioxidant effect of polyphenols and natural phenols A polyphenol antioxidant is a type of antioxidant containing a polyphenolic substructure and studied in vitro. Numbering over 4,000 distinct species mostly from plants, many of these compounds have antioxidant