Ongoing discussion for students in Chemistry III

Please abide by the following when posting to this blog:
1) no profanity & no attacking another's perspectives
2) for each claim or idea that you put forth, justify your idea with at least two SOLID pieces of evidence & coherent reasoning (more evidence presents a stronger argument)
3) feel free to disagree and/or agree with each other, however know that you need to justify why you feel or think the way you do
4) any questionable content will not be posted
5) feel free to add topic-specific or claim-specific links, URLs, and images in your posts

Wednesday, October 12, 2011

Luminescence

Luminescence is defined as the emission of light from a source that has not been heated. Luminescent light can be found all around us and is produced through chemical reactions, the breaking of crystals, or electric energy. There are many different types of luminescence:

- Chemiluminescence: Perhaps the most common is chemiluminescence. When two reactants respond to one another, the result is a product and light.

- Bioluminescence: Falling within the same category is bioluminescence, which is the emission of light by a living organism. It is a type of chemiluminescence because organisms that emit bioluminescence produce luciferin. The luciferin that these organisms produce reacts with oxygen to create light, so it is therefore a chemical. This classifies bioluminescence as a sect of chemiluminescence.

- Triboluminecence: Triboluminecence is the production of light when material is pulled apart or crushed. The breaking of certain chemical bonds and the separation of electric charges produce light. This can be seen in the breaking of sugar crystals (like Life Savers) or the peeling back of tape.

If I were to redesign New York City using one type of photoemitter, I would choose bioluminescence hands down. Out of the three types of luminescence that I have mentioned, it is by far the most efficient.

Chemiluminescence requires an external chemical reaction to occur which wouldn’t exactly be effective in lighting up the city. Even if you were to place these chemicals in some sort of case or tube, there would still be the question of where to put the materials once the chemical reaction occurs and they can no longer be used for light. The chemicals used in chemiluminescence are often times very dangerous and toxic (definitely not something that could be left unattended to light a street corner). Once used, they would add to New York’s already-abundant supply of waste. In addition, if one were to use chemiluminescence, constant chemical reactions would have to occur in order for there to be enough light for a person to get done what they need to. This means that this would not be a renewable energy source because it would require a steady supply of chemicals. In short, chemiluminescence would not be efficient because it requires sometimes-dangerous chemicals, would not be renewable, and would produce an abundance of waste.

Triboluminescence would also prove to be very ineffective. To begin with, the amount of light produced in triboluminescence is around 1% of the light produced from a standard 60-watt light bulb (and that is if the mass of the bulb were equal to the mass of the substance being used in triboluminescence). Since the particles being crushed or broken are often no larger than a grain of sugar, it would require a lot of salt to get anywhere near producing as much light as one light bulb. In addition to it not being a useful amount of light, it is also not efficient. Triboluminescence requires the breaking or crushing of certain particles. Machines, of course, could be made to crush particles like sugar, but they would end up using the same amount of electricity and energy (if not more). In short, triboluminecence does not produce enough light to be effective and requires too much effort to produce light.

Therefore, bioluminescence would be the best way to light New York City. It most commonly occurs in marine animals. Some use bioluminescence as a way of attracting prey. Contrastingly, others use it as a way of distracting or confusing their attacker. Unlike chemiluminescence or triboluminescence, bioluminescence is produced naturally in organisms. Therefore, it would not require cumbersome crushing and it would not involve chemicals or chemical disposal. What is nice about bioluminescence is that the animals create the light with a chemical that they possess naturally. This makes it a renewable light source because luciferin does not need to be synthesized or purchased. If we can harness the luciferin in animals that use bioluminescence, lighting would not be an issue. The luciferin would simply be reacting with the air. This would be particularly effective in areas such as central park. Trees could become a source of light if luciferin could be infused and reacted with the air. Lampposts would no longer be necessary. This would also add to the aesthetic of the city. Instead of streets being lined with ugly lampposts, they could be lined with trees that double as lights. Any area where a person desires light could be infused with luciferin. Therefore, that area would be a natural light.

In addition, the use of bioluminescence would decrease New York’s electricity use and therefore carbon footprint. Reducing our emission of carbon into the atmosphere is vital for the future and the preservation of our planet. If we could use bioluminescence, so much energy could be saved.

On a slightly less practical note, recent AIDS research has led to the development of glowing-cats. Scientists modified genes in the cats in an attempt to create a cat that is resistant to feline AIDS. They succeeded in doing so and marked the altered genes with bioluminescence. This made it easy for them to see which gene had to be altered. These cats literally glow. What if we utilized cats like this? Imagine getting up in the middle of the night and, instead of flipping on light after light on your way to the bathroom, you just grabbed your cat. Domesticated cats are the second most popular pets in the United States. So why not have your best friend double as a source of light? Electricity bills would decrease dramatically!

Thousands of organisms use bioluminescence. They use it to get food, to distract predators, and as a form of communication. If they can use it, and use it effectively, then why can’t we?



Sources:

http://en.wikipedia.org/wiki/Triboluminescence

http://en.wikipedia.org/wiki/Chemiluminescence

http://en.wikipedia.org/wiki/Bioluminescence

http://www.candyblog.net/blog/item/lifesavers_pep-o-mint_wint-o-green/

http://en.wikipedia.org/wiki/File:Chemoluminescent_reaction.jpg

http://www.msnbc.msn.com/id/44476309/ns/health-aids/t/green-glowing-cats-are-new-tool-aids-research/#.TpZAzk8YUxY

http://www.writers-free-reference.com/10pets.htm

http://www.metrolic.com/wp-content/uploads/2011/02/firefly1.jpg

http://www.202020diet.com/Images/CheckMark.jpg

2 comments:

Anonymous said...

(This is from Emma)
Hi Katie! I agree that bioluminescene would reduce our carbon footprint. Although it seems silly use biolumiescene to light animals, if we used biolumiescene to light pigeons it would be really beneficial considering pigeons are everywhere... NY would never be in the dark. - Emma

Anonymous said...

Although the use of Bioluminescence is certainly interesting, the notion of harnessing the chemicals from an organism to satisfy our need for light is unsettling. How exactly could we extract enough luciferase from organisms in order to illuminate the entire city?