Caffeine is a
xanthine alkaloid compound that acts as a
stimulant in humans. Caffeine is sometimes called
guaranine when found in
guarana,
mateine when found in
mate, and
theine when found in
tea. It is found in the
leaves and
beans of the
coffee plant, in
tea,
yerba mate, and
guarana berries, and in small quantities in
cocoa, the
kola nut and the
Yaupon Holly. Overall, caffeine is found in the beans, leaves, and fruit of over 60 plants, where it acts as a natural
pesticide that
paralyzes and kills certain
insects feeding upon them.
Caffeine is a central nervous system (CNS) stimulant, having the effect of temporarily warding off men drowsiness and restoring alertness. Beverages containing caffeine, such as coffee, tea, soft drinks and energy drinks enjoy great popularity: caffeine is the world's most widely consumed psychoactive substance. In North America, 90% of adults consume caffeine daily.
Many natural sources of caffeine also contain widely varying mixtures of other xanthine alkaloids, including the cardiac stimulants theophylline and theobromine and other substances such as tannins.
Vitrification is a process of converting a material into a glass-like amorphous solid which is free of any crystalline structure, either by the quick removal or addition of heat, or by mixing with an additive. Vitrification is a proven technique in the disposal and long-term storage of nuclear waste or other hazardous wastes. Waste is mixed with glass-forming chemicals to form molten glass that then solidifies, immobilizing the waste. The final waste form resembles obsidian and is a non-leaching, durable material that effectively traps the waste inside. The above image demonstrates this process.
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