Lava Lamps

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Lava Lamps

• Two ingredients (water and wax) are mutually
  insoluble
• Heat source tweaks the
  density of one component so when warmed, it
  floats to the top
• Upon cooling, it is denser than the other
  component and sinks to the bottom
• Displays random motion

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Beer
A chemical, biological, and physical process
Brewing
Batch Process
Yeast
Sugar
Ethanol CO2
Bottling
Continuous Process
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http//encarta.msn.com
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Peeps

• Candy made from sugar, gelatin, potassium
  sorbate, and wax
• In 1952, it took 28 hours to make one peep
  production is now 1.2 billion/yr (enough to
  circle the Earth twice)
• Researchers at Emory University have confirmed
  that peeps are difficult to destroy
• Peeps have zero fat grams
• Sucrose crystallization, cross-linking of gelatin
  molecules, and glassy formation of sucrose and
  gelatin during processing

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Making Peeps
Squeezed onto a conveyor belt
Peeps get their eyes put on
Taking a ride down the conveyor belt
Dropped into boxes
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Ice Cream

• Water (milk and cream), sweetener (corn syrup or
  sugar), flavorings, emulsifiers, stabilizers, and
  milk fat
• Ice cream contains 20-50 air
• Ice cream has a colloidal structure tiny air
  bubbles and ice crystals are dispersed liquid
  water and destabilized fat molecules
• Ice cream has to be cooled below 0oC ( -16oC)
  because of the freezing point depression, a
  colligative property
• Size of the ice crystals affects quality, and
  crystal size depends on freezing rate

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Jell-O

• Sweetened, flavored and colored gelatin
• Gelatin processed collagen, a structural
  protein derived from pork skin, cattle bones, and
  cattle hide
• Jell-O patented in 1845
• Marketed as an inexpensive dessert during the
  Depression a convenience dessert in the 1950s
  edible entertainment in the 1990s
• Jell-O can be used to dye your hair, clean the
  dishwasher, and deodorize cat litter
• Fresh or frozen pineapple contains an enzyme that
  prevent Jell-O from setting

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Plastic Bags

• Petroleum and natural gas are the sources for the
  key materials in plastic
• Types of plastic depend on degree of branching of
  the polymer chain
• LLDPE thick, glossy shopping bags from the mall
• LDPE garment bags from the dry cleaner
• HDPE grocery bags
• Disposal problems
• Biodegradable bags
• Starch ? lactic acid ? polylactide
• Add a UV-light absorber to the polymer so that it
  degrades when exposed to sunlight

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Sticky Notes

• More than 1 trillion sticky notes have been sold
  worldwide since 1980
• 3M adhesive discovered by accident
• Acrylic co-polymer of microsphere
• When sprayed on a surface, the solvent
  evaporates, forming a sparse monolayer with a
  pebbled surface
• This allows a limited number of touch points,
  which makes the paper removable and restickable
• Banned from libraries, archives because of the
  slight residue left from the adhesive

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Contact Lenses
Materials, diffusion, fluid transport

• Regulated by FDA
• Cornea does not have blood vessels
• Cells get oxygen from air and nutrients from
  fluids

• Previously used PHEMA
• Now use hydrogels / silicones (50 water)
• How do you minimize bacteria, fungus, etc?

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Computer chips
Made primarily by Chemical Engineers! Integrated
circuits are composed of many layers of
semiconductors, conductors, and insulators.
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Step and Repeat Exposure Systems
1/1000th of a human hair