All posts by Kevin J

Failed Experiment Leads to Serendipity

How Algae is Converted into Energy
How Algae is Converted into Energy

As many of you know, The IB Group 4 project was not too long ago for us. Our goal was to investigate how to help better the fight against poverty; so, my group decided to investigate a renewable source of energy, more specifically, algae. Now algae had already been known as a bio-fuel, but there are some difficulties in cultivating and growing enough algae for this to be a sufficient substitute for more commonly used fuels. We were to determine what pH value of water would the algae growth rate be the greatest. After much investigation, we determined that it would be best to test pH levels of 8-12. We took 5 different samples of the same species of algae and placed them into 5 different containers of different pH levels (from 8 to 12). Each container had the same variables affecting the algae growth; the humidity was constant, the amount of sunlight was constant, the amount of nutrients was constant. Naturally, it is our duty as scientists to ensure that the variables are controlled to ensure the data we collect retain its integrity.

But when deciding how to determine which algae had grown the fastest, we were stumped. We could not take the mass of the algae because algae absorb water and we do not want water masses and we could not measure the volume of the algae because it does not take a rigid shape. We had met our first roadblock.

Finally, Mr. Smith suggested that we use a bomb calorimeter to measure the energy given off when the algae are burned. Theoretically, the more massive the algae, the more energy will be given off. So we were back into action mode. We extracted the algae from their containers and placed each sample into an incubator to evaporate any remaining water.

The next day, all the water had evaporated from the algae. We promptly set up the calorimeter, stuck a needle into a cork, prepped a stopwatch, prepared the distilled water and lit the algae. It did not burn. We poked and prodded for minutes at a time but the algae refused to catch fire. We had failed. Lost in a world of our own misery my team looked down, ashamed of our brief role as scientists as I continued to light the algae without reward. And then something clicked. I could see the heads of my group mates slowly rise up as they realized what we have created. Algae that does not burn! More excited than ever, we decided to test our flame resistant plant by placing it on a stack of very flammable paper towels and lighting it. What we found was astounding. Not only, were the algae flame resistant, but it also helps preserve what was underneath. The paper towel surrounding the algae were all burnt, but the paper towel directly underneath was untouched.

asbestos

But why is this important? How does it help fight poverty? Usually, a substance known as Asbestos is integrated into building material to give that object a fire resistive property, but what my group 4 had done was create an organic substitute for asbestos. Though we do not know any side effects from using the algae to retard flames, we do understand that long term exposure to asbestos causes cancerous diseases as well as non-cancerous diseases to the throat, lungs and in some cases, the heart (shown above). We also must reinforce the fact that Algae is an organic substance, meaning it is both easily accessed and environmentally friendly. Hopefully, our findings are significant enough to call for further investigation such as determining how to reproduce such algae, and determining possible health risks from exposure. Perhaps in the future, houses will be lined with algae instead of asbestos.

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“Algae Growing Conditions.” Growing Algae. Web. 25 Sept. 2011. <http://www.growing-algae.com/algae-growing-conditions.html>.

Kriscenski, Ali. “POWER YOUR CAR WITH ALGAE: Algae Biocrude by LiveFuels.”Inhabitat – Green Design Will Save the World. 22 Oct. 2007. Web. 25 Sept. 2011. <http://inhabitat.com/power-your-car-with-algae-algae-biocrude-by-livefuels/>.

“What Are Asbestos-Related Lung Diseases?.” National Heart Lung and Blood Institute. U.S. Department of Health & Human Services, May 01, 2011. Web. 25 Sept 2011. <http://www.nhlbi.nih.gov/health/health-topics/topics/asb/>.

With a Flick of the Wand…

The first time I saw it, I was amazed. The comforting warm that radiated from it, the welcoming hue that overflowed the room, the occasional snap that filled the silence of the night. Of course, I am speaking of fire.  And with any good fire, there is always an accompanying pale of water. Knowing that water puts out flame is one of the first things that we learn; yet the same simple principle is applied today to combat wildfires and house fires. However, this often causes water damage to the environment, not to mention the need for large amounts of water to be available. But what if there was a way to extinguish such fires with just a flick of a wand?

http://www.ericksonaircrane.com/firefighting.php
http://www.ericksonaircrane.com/firefighting.php

No, I am not speaking of Harry Potter’s magic wand. Scientists at Harvard have developed their own “wand” that can extinguish flame, using electric fields. The “wand” generates an electrical field that can suppress flames very quickly and at a distance as well. Researcher Ludovico Cademartiri demonstrated at the 241st National Meeting of American Chemical Society how such a device worked. He plugged in a 600-watt amplifier and attached the “wand” to the amplifier. With the power of 600 watts, the “wand” was able to generate an electric field of about 1 million volts per meter. While that seems like an absurd amount of energy, 1 million volts per meter is “approximately the field necessary to generate a spark in dry air”, and is therefore, not dangerous to a healthy human. The scientists proceeded to move the rod towards an open flame, about 50 centimeters tall, and almost instantly, the flame died.

A phenomenon like this deems the word “wand” almost fitting, but the concepts behind it are actually quite simple. Inside of any flame, there are electrons, Ions and soot, which all respond to electric fields. By generating a current through the “wand” an electrical field is created and like opposite sides of a magnet, the field generated by the wand repels the electrons, ions and soot inside of the fire. This resulted in the fire being, “pushed” away from its fuel source, and without fuel, the fire will die.

Of course, in real life, firefighters are faced with much larger flames, so a small wand would not be much help. However, scientists are working to increase the distance that the field affects flames, and increase the power of the field generated, so large scale fires can be combated. As this technology develops, the size of the “wand” will decrease, as will the wattage it uses. It seems that only a tenth of what Cademartiri used in his demonstration is needed to put out a that same 50 centimeter flame. Nonetheless, adapting this electrical “wand” for the use of firefighters would be very beneficial to both the economic and environmental aspects of firefighting. Advancements in the “wand” technology will allow firefighters to potentially replace their use of water to put out flames, effectively removing the issue of water damage to the building as well as their reliance of an available water source. Cademartiri also reported that the “wand” could be used to control the heat distribution of flames, so this technology would not be limited to just firefighters. Any technology that requires constant care for overheating can benefit from this technology, as the “wand” and redistribute the heat to prevent overheating.

Works Cited
Choi, Charles. “Electric Wand Makes Fire Disappear.” Daily Nature and Science News and Headlines | National Geographic News. 29 Mar. 2011. Web. 6 Apr. 2011. <http://news.nationalgeographic.com/news/2011/03/110329-electric-wands-fire-firefighters-extinguish-science-harvard-chemical/>.
Melville, Kate. “Electrical “wand” Extinguishes Fires.” Science News, Research And Discussion. 28 Mar. 2011. Web. 6 Apr. 2011. <http://www.scienceagogo.com/news/20110227210048data_trunc_sys.shtml>.

The “Journey” of Music to Your Ears

Recorded music has gone a long way since its beginning as phonographs (1877) to the era of vinyl records, to CDs, and finally mp3 files. As a teen and an international student in today’s world, I am constantly plugging into my music. Hardly ever do I leave the house without my Ipod in hand. Whether I am just on my way to school, or on a plane, my headphones never leave my ears. Only recently have I questioned how a digital file can be transformed into audible noise.

In order to begin to understand the process, we must first understand how MP3 files work.

The MP3, first introduced by German company Fraunhofer-Gesellshaft, is a digital audio file format, which most of us use to store our audio files. It uses “lossy data compression” in order to replicate a large amount of data (the original sound file) into a smaller amount of space (the mp3 file) but still retain sound quality like the original. The replicate file, when played, still sounds the same as the original, but uses a smaller amount of bits. This is because “lossy data compression” does not make an exact copy of the original. Instead, it only copies certain pieces of data, and discards the rest. Luckily, MP3 files have been configured so that only the sounds that are outside our hearing spectrum are not replicated. This proves to be much more efficient because even if that sound were to be included in the MP3 file, none of us would be able to hear it.

Typically, human ears can only hear sounds within the frequencies of 20 Hz to 20,000 kHz.
Typically, human ears can only hear sounds within the frequencies of 20 Hz to 20,000 kHz.

Now that we have a basic understanding of how MP3 files work, all that is left is to determine how MP3 files are converted back into audible noise through your earphones.

The set up of a standard pair of earphones is quiet simple actually. The earpiece consists of one magnet, one copper wire attached to a thin sheet of plastic and a front and back cover. The pictures below show each part and how they fit together.

from left to right.* back case, front cover, earphone jack (top), copperwire attached to a plastic sheet, magnet
from left to right.* back case, front cover, earphone jack (top), copper wire attached to a plastic sheet, magnet
The magnet fits in the center of the back case. The copper wire is then fitted around the magnet. The front cover (right) fits infront of the plastic sheet
The magnet fits in the center of the back case. The copper wire is then fitted around the magnet. The front cover (right) fits in front of the plastic sheet

When you plug in your headset and press play, you feel a small vibration on the earpieces. This is because the headphones are actually vibrating in order to produce noise. Your music player reads the mp3 files and converts that file into an electric current, an audio current, if you will. This current runs through the length of the wire, and reaches the earpiece. The wires are actually attached to the copper coil, meaning the audio current moves directly through it. The copper coil is in suspended in a static magnetic field, which is produced by the magnet it surrounds. But when an audio current passes through the coil, it produces an alternating magnetic field, which causes both the copper wire and its attached plastic film to vibrate. This vibration also moves the air around it, producing sound.

With little over 100 years of development, Recorded audio has moved from a stylus moving across a series of groves and progressed into the digital age, where audio is read as a series of codes. In a time where technology is constantly progressing and top of the line products from only 3 years ago, are rendered useless in the face of today’s technology, there is no guessing how audio files will be recorded in the future.

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Works Cited:

Bellis, By Mary. “History of MP3.” Inventors. Web. 31 Oct. 2010. <http://inventors.about.com/od/mstartinventions/a/MPThree.htm>.

Brain, Marshall. “HowStuffWorks “How MP3 Files Work”” HowStuffWorks – Learn How Everything Works! Dec. 2006. Web. 31 Oct. 2010. <http://www.howstuffworks.com/mp3.htm>.

Explainthatstuff.com. “How Headphones Work: A Simple Introduction from Explain That Stuff!” Explain That Stuff! Science and Technology Made Simple. 7 May 2007. Web. 31 Oct. 2010. <http://www.explainthatstuff.com/headphones.html>.

Wikipedia. “Headphones.” Wikipedia, the Free Encyclopedia. 4 Mar. 2003. Web. 31 Oct. 2010. <http://en.wikipedia.org/wiki/Earphones>.

Wikipedia. “MP3.” Wikipedia, the Free Encyclopedia. 30 Sept. 2001. Web. 31 Oct. 2010. <http://en.wikipedia.org/wiki/MP3>.