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So we fix our eyes not on what is seen, but on what is unseen, since what is seen is temporary, but what is unseen is eternal.
The Profile Zanzibar Age. 39 Gender. Female Ethnicity. that of my father and his father before him Location Altadena, CA School. Other » More info. The Weather The World The Link To Zanzibar's Past
This is my page in the beloved art community that my sister got me into: Samarinda Extra points for people who know what Samarinda is. The Phases of the Moon Module CURRENT MOON Writings
Poetry The Tree and the Telephone Pole The Spider I Do Not Know Their Names The Mouse Blindness La Plante The Moon Today I am Young A Night Poem Celestial Wandering Siren of the Sea If I Were a Dragon To the Dreamers Leave the Sky The Honor of the Oyster Return From San Diego War My Study Defeat A Late Summer's Night Of Dragons and Men Erebus The Edge of the World The Race Dragon's Spirit The Snake's Terror Spirit Island Metaphysics Metaphysica Transponderae Metaphysics and the Middaymoon Of Adventures in Foreign Lands The Rogue Wave: The Unedited Version Adventures in the PRC Voyage of Discovery Drinking the Blood of Goats Ticket for a Phantom Bus Os peixes nadam o mar Three Villages Far Away The River Weser Children I Should Have Kidnapped, Part I Let's Get You Out of Those Clothes Radishes Three-Piece-Lawsuit If Underwear Could Speak Croc Hunter/Combat Wombat
My hero(s) Only My Favorite Baseball Player EVER Aw, Larry Walker, how I loved thee. The Schedule
M: Science and Exploration T: Cook a nice dinner W: PARKOUR! Th: Parties, movies, dinners F: Picnics, the Louvre S: Read books, go for walks, PARKOUR Su: Philosophy, Religion The Reading List
This list starts Summer 2006 A Crocodile on the Sandbank Looking Backwards Wild Swans Exodus 1984 Tales of the Alhambra (in progress) Dark Lord of Derkholm Do Androids Dream of Electric Sheep? The Lost Years of Merlin Harry Potter a l'ecole des sorciers (in progress) Atlas Shrugged (in progress) Uglies Pretties Specials A Long Way Gone (story of a boy soldier in Sierra Leone- met the author! w00t!) The Eye of the World: Book One of the Wheel of Time From Magma to Tephra (in progress) Lady Chatterley's Lover Harry Potter 7 The No. 1 Lady's Detective Agency Introduction to Planetary Volcanism A Child Called "It" Pompeii Is Multi-Culturalism Bad for Women? Americans in Southeast Asia: Roots of Commitment (in progress) What's So Great About Christianity? Aeolian Geomorphology Aeolian Dust and Dust Deposits The City of Ember The People of Sparks Cube Route When I was in Cuba, I was a German Shepard Bound The Golden Compass Clan of the Cave Bear The 9/11 Commission Report (2nd time through, graphic novel format this time, ip) The Incredible Shrinking Man Twilight Eclipse New Moon Breaking Dawn Armageddon's Children The Elves of Cintra The Gypsy Morph Animorphs #23: The Pretender Animorphs #25: The Extreme Animorphs #26: The Attack Crucial Conversations A Journey to the Center of the Earth A Great and Terrible Beauty The Absolutely True Diary of a Part-Time Indian Dandelion Wine To Sir, With Love London Calling Watership Down The Invisible Alice in Wonderland Through the Looking Glass 20,000 Leagues Under the Sea The Host The Hunger Games Catching Fire Shadows and Strongholds The Jungle Book Beatrice and Virgil Infidel Neuromancer The Help Flip Zion Andrews The Unit Princess Quantum Brain The Immortal Life of Henrietta Lacks No One Ever Told Us We Were Defeated Delirium Memento Nora Robopocalypse The Name of the Wind The Terror Sister Tao Te Ching What Paul Meant Lao Tzu and Taoism Libyan Sands Sand and Sandstones Lost Christianites: The Battles for Scripture and the Faiths We Never Knew The Science of God Calculating God Great Contemporaries, by Winston Churchill City of Bones Around the World in 80 Days, by Jules Verne Divergent Stranger in a Strange Land The Old Man and the Sea Flowers for Algernon Au Bonheur des Ogres The Martian The Road to Serfdom De La Terre � la Lune (ip) In the Light of What We Know Devil in the White City 2312 The First Fifteen Lives of Harry August Red Mars How to Be a Good Wife A Mote in God's Eye A Gentleman in Russia The Fatal Conceit: The Errors of Socialism Seneca: Letters from a Stoic | How to Cut Diamonds with Scissors Made of Water Saturday. 2.16.08 12:49 pm So in fluid mechanics we were learning about carbon nanotubes. These tiny cylinders (about 10E-09 m in diameter, hence the name) are likely to revolutionize many sectors of industry. They are made out of carbon, with a unique chemical structure making them extremely strong. Like diamonds, they are made of carbon, and their bond structure makes them even stronger than diamonds, depending on which way you try and break them. They tend to aggregate into ropes, and you can fuse them together, creating the possibility of making them into extremely strong wires. They are also good at conducting heat. So. How does this have to do with a pair of water scissors? Well, given that carbon nanotubes are so strong, they are exceedly difficult to cut. Engineers would like to cut them to whatever length they desire for their projects, but now they have to deal with the fact that they're going to be whatever length they grow to be (perhaps a couple microns). Thus the problem was put to researchers: How can we cut a micron-scale nanotube accurately when its bonds are stronger than a diamond's? We must make a pair of nanoscissors! One group tried to do it chemically, sort of how some people cut DNA. But they had to use extremely strong chemicals, and they always ended up destroying the carbon nanotubes instead of cutting them. Another laboratory decided to cut them physically by mixing them with extremely tiny bits of zircon (a very hard and resilient mineral), and then shaking the container. Unfortunately, this method also usually reduced the carbon nanotubes to bits or damaging them instead of cutting them. Enter the group at Brown. Fluid mechanicians, they decide to cut the carbon nanotubes using water. How? Cavitation, of course! Cavitation is a process by which turbulence or disturbences (pressure waves, what have you) in a liquid cause tiny areas where the pressure is low enough for the liquid to turn into a gas. This is kind like boiling, except boiling is usually accompanied by temperature rising enough to turn the liquid to a gas, because the state of a material is dependent on both temperature and pressure. But even when boiling, the first bubbles usually nucleate on contaminating particles or along the wall of the container, where local pressure is slightly lower. After these bubbles form, they almost immediately collapse after the pressure goes back to normal. They collapse at super-sonic speed, and because the process is adiabatic, as the volume shrinks, the temperature goes way up-- to the tune of some 5000 degrees C. The energy produced very locally by this process is so high that the popping bubbles often give off sparks as they collapse, as well as pressure waves that can be heard as very loud sounds. This aspect of cavitation makes it a huge engineering concern, and a big concern for secret spy nuclear submarines (see: Hunt for the Red October, "We're cavitating!!!") Cavitating makes a huge number of extremely loud pops, which can be easily picked up by the sonar on other vessels (i.e., Commies!!). The skins of submarines are optimized to reduce cavitation as much as possible, but it depends on what maneuvers you are doing. Cavitation can also happen in pistons and pipes and near the propellors of ships. The energy from the popping bubbles wears huge pits into the metal in these systems, incurring a large cost and necessitating the replacement of parts well before they should be worn out. Cavitation is also a concern when using ultrasound on the body, because pressure waves like those used in ultrasound, if it's turned up too high, can induce cavitation in your blood, wreaking havoc on the nanostructures in your vessels. (Don't worry, they never turn it up that high!) Cognizant of the effect of cavitation on nanostructures, the people at Brown decided to see how carbon nanotubes reacted to cavitation. As it turns out, if you put a lot of carbon nanotubes into water, when the bubbles form, the nanotubes are attracted to the low pressure region and in a sense adhere to the surface of the bubble. When it collapses, the surface area over which the nanotubes are spread decreases drastically, and the nanotubes buckle... along eigenmodes! If you imagine pushing a rug from either side, the rug will buckle in a series of folds that are usually evenly spaced. These are the eigenmodes of the rugs, and the spacing between them would be the eigenspacing, as eigen just means "characteristic" in german. But you can change the eigenspacing of your rug by pushing it together with different energies. (It will also have different eigenspacing depending on how stiff a rug it is. You can imagine that a doormat might have only one eigenmode, while a blanket would have a lot.) So, by controlling the size of the bubbles that form (by controlling the kind of sonic waves that initiate the cavitation), you can cut the carbon nanotubes to pretty much any length you want! Using scissors.... MADE OF WATER!!! Anyway, that was a really cool class. 5 Comments. Speaking of diamonds, have you seen... Diamonds in the microwave? » ikimashokie on 2008-02-16 01:52:40 Add that to random's list of ways to die. Death by cativation of the blood. Ew. Did you know that the pistol shrimp uses the same phenomenon to stun or kill prey? Of course you did. » middaymoon on 2008-02-16 02:25:27 The chemical properties of carbon nanotubes (and other carbon nanostructures like fullerenes) are interesting as well. While carbon is normally thought to act more like an insulator than a conductor, carbon nanotubes have pi bond delocalization along their surfaces, making them great conductors. Altering the arrangement of pi bonds over the surface through chemical means can also transform carbon nanotubes into semiconductors. There's a lot of research going into using carbon nanotubes in circuits and other electrical applications. Carbon chemistry is so awesome. All hail the tetravalent element--the basis of all life as we know it (or rather, as we have confirmed exists)! » ranor on 2008-02-16 02:55:29 Oh, and by the way. I've read that microtubials in brain cells give our brains their ability to tap into quantum fluctuations that are too small to normally make any chemical differences. How neat is that? » middaymoon on 2008-02-16 05:59:53 Re:middaymoon That's hotly debated. The idea of quantum consciousness/quantum mind is a fringe theory in modern neuroscience and physics. I think the idea itself is very cool, but we are a LONG way away from a paradigm shift in the direction of quantum consciousness. » ranor on 2008-02-16 10:19:05
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