Stories tagged Physical Science
Nano at home!: Forget those super-sterile clean rooms. The DIY Nano app lets you explore nanoscale science in the comfort of your own home!Courtesy NISE NetworkWhen things get really really small (nanoscale small), they behave completely differently! For example, gold at the nanoscale can look purple, orange, or red; static electricity has a greater effect on nanoparticles than gravity; and aluminum (the stuff your benign soda cans are made of) is explosive at the nanoscale!
If you want to experience some of these nanoscale phenomena first-hand, check out whatisnano.org, or download the DIY Nano app. The website and the app were both created by the Nanoscale Informal Science Education Network (NISE Net for short), and have videos and activity guides, complete with instructions and material lists, so you can do some nano experiments at home! The app was a Parents' Choice award winner for 2012, and was featured in Wired Magazine's review of apps. Definitely worth a look!
Have fun exploring nanoscale properties!
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Spooky action: not just for Halloween anymore.Courtesy Photo and graphic by author plus Wikimedia CommonsThis is a perfect post for Halloween. A really scary story involving quantum physics. Let me begin by saying that this stuff is absolutely mind-boggling. I’m not even sure I can explain it. Albert Einstein himself – the bravest theoretical physicist there ever was - called it “Spooky action at a distance”, that’s how much it scared him. What’s even more disturbing is that scientists now are reporting that this spooky action has gotten even spookier! I’m talking back-from-the-dead-zombie spooky! Let me feebly try to explain.
One dark and stormy night there were two sub-atomic particles – photons, let’s say – that are joined together like a two-headed freak show turtle. Wait, probably a bad analogy – how about this: like a set of identical twins? That works. Think of twins, Larry and Ralph. They’ve interacted with each other since birth, acting exactly the same way no matter where they were. If Larry ate a cheeseburger for lunch, Ralph had one, too. Anyway, in the world of quantum mechanics, this joining of two particles is called entanglement.
At quantum levels all rules of physics are thrown out like a rotting pumpkin on All Saints Day. As I understand it, particles don’t really exist in one particular spot or state on the time-space continuum –but rather in all their probable states at the same time. It has to do with a deal called superposition, and is all about probability. Which means until they’re measured or observed in some way, they live in a constant state of uncertainty. Once one of them gets measured, and a value is placed on it, the uncertainty is eliminated, and at that point it locks into some sort of “existence”. I think so anyway. But – and this is a really big but – just by measuring it, the particle dies. Or it’s state of uncertainty dies– I’m not sure which. Something gets killed. Does this make any sense? Not to me, but I’ll continue anyway.
So, with an entangled pair of particles, things get kind of weird. When two particles are entangled – i.e. physically interacting - with some sort of correlation (or anti-correlation), – that interaction remains no matter where they are located in relation to each other. You measure a value in one of the entangled particles, you can be certain the other particle instantly has the same value. In a correlated pair, if you see that one particle has an up spin, you’ll know right away the other has an up spin, too. In a normal world analogy, if you see Larry bobbing for apples at a party tonight, you’ll know Ralph is somewhere with a wet head.
This theory has been successfully tested several times on pairs of entangled photons separated by 80 some miles. It would matter not a whit if they were separated by a 100 billion lightyears, some unexplained force tying them together, would give the same results.
Now here comes the really scary part. Quantum physicists are now predicting that the same kind thing can happen when the two entangled particles don't even exist at the same time. This is called an entanglement swap. It involves removing a particle from one entangled pair, and using it to create a new pair with another particle removed from a different entangled pair. I know. Blah, blah, blah. But let’s see if I can help you (and me) understand.
Let’s start with an entangled pair of photons, our old pals “Larry and Ralph” again. You decide to measure Larry’s spin. It’s a down spin. So far so good. But unfortunately, your measurement leaves his twin Ralph, all alone. “You’re dead to me!” Ralph screams! And Larry is dead because you gave him a value (his spin). Ralph now wanders about by himself (with the same down spin as Larry of course). This is called disengagement. A little later, you create another entangled pair of photons, this time named “Jane and Sally”. They’re not very happy– always bickering, always fighting over whether they’re actually particles or packets of waves – you know, the usual photon sibling stuff. Anyway, after a while they become disengaged (somehow evidently without measuring and killing one – I’m confused here). Anyway, Jane leaves in a huff and eventually ends up hooking up with the very lonely Ralph. They’ve now done the old entanglement swap.
This leaves us with one dead photon, Larry, and one abandoned photon, Sally. They come from two different disengaged pairs and couldn’t be more unrelated. But, thanks to the screwy world of quantum mechanics Larry has somehow returned from the dead and is suddenly now entangled with Sally. They are an entangled pair. Sally wasn’t even alive when Larry died! But now she’s stuck in a paired entanglement with a stupid zombie. Now that's frightening. I’m sure Einstein is spinning in his grave.
If my telling of this bizarre quantum tale hasn’t scrambled your brains, or made the hairs on the back of your neck stand up, you can try to learn more at the below links.
SOURCES AND LINKS
New Scientist story
Scientific American story
Niels Bohr – the genius responsible for this stuff
Quantum entanglement
Uncertainty principal
Schrodinger’s Cat A cat's both dead and alive until you look inside the box.
Graphene fixes itself: Graphene uses loose carbon atoms to re-knit its damaged structure.Courtesy ksoAs a happy accident, scientists from the University of Manchester learned that graphene (sheets of carbon atoms arranged in a honeycomb crystal lattice, just one atom thick – think chicken wire) can repair itself spontaneously. Graphene is a semi-metal that conducts electricity very easily. It has potential uses in not only electronics, but also DNA sequencing, desalination, and it has been found to be a great antimicrobial.
The Manchester researchers were originally trying to understand how metals react with graphene, which will be an important part of incorporating it into everyday electronic devices. They found, much to their dismay, that some metals actually damaged graphene’s structure by punching holes in its neatly-arranged lattice. This is not a good thing if you’re trying to create a graphene-based device. However, quite unexpectedly, the graphene started to mend itself spontaneously, using nearby loose carbon atoms! As stated by the Scientific Director at the Daresbury Laboratory, Dr. Quentin Ramasse, this could mean the “difference between a working device and a proof of concept with no real application.” It also means that graphene just jumped to the top of my “baller carbon allotropes” list.
Sprayable Battery: Move over spray-tan, there's a new aerosol in town.Courtesy Alex WalkerResearchers from Rice University have rethought the battery. Typically, batteries are made up of 5 layers: a positive and negative electrode, each with a metal current collector, and a polymer separator. These layers are manufactured in sheets and then rolled into cylinders. Rice researchers realized that each of these layers were available, or could be created, in sprayable form. They used lithium titanium oxide and lithium cobalt oxide for the anode and cathode, existing metallic paints and carbon nanotube mixtures for the current collectors, and a chemical hodge-podge with a very lengthy name for the separator layer. The result is an ultra thin (a fraction of a millimeter thick) lithium ion battery.
In their first experiment, researchers sprayed each consecutive layer onto nine bathroom tiles, topped with a solar cell. The resulting batteries were able to power 40 LEDs for six hours.
In its current state, this method is too toxic to be used outside a controlled environment, but with a little tweaking, a safe alternative will be found. At that point, any surface could be a battery!
Ferrofluid + Watercolor= Purty: Photographer Fabian Oefner captures the beautiful effects of combining watercolor and ferrofluid.Courtesy Fabian OefnerEver wonder what adding watercolor to ferrofluid might look like? Yeah, me neither. But photographer Fabian Oefner did, and this is the result – cool, psychedelic, maze-like images!
Ferrofluid is a colloidal liquid that’s made up of nanoparticles of iron, suspended in a fluid (usually water). Because it’s basically liquid iron, it becomes magnetized when exposed to a magnetic field, and ends up looking like a spiky mound. What Fabian did to create these cool images was to inject watercolors into a magnetized puddle of ferrofluid. The nanoparticles of iron then rearrange themselves into channels and pools to accommodate the paint, creating these colorful labyrinths. I highly recommend watching the video that demonstrates this process – it’s mesmerizing!
Sensing Strain: This new system will allow you to detect strain anywhere, in any direction, and at any time.Courtesy Bruce WeismanScientists at Rice University developed a new type of paint, infused with carbon nanotubes, that can detect strain in bridges, buildings, and airplanes before the signs of deformation become visible to the naked eye.
This is how it works: The paint is applied to the desired structure and allowed to dry. A laser beam is then focused on the structure, which excites the carbon nanotubes, and in turn, causes them to fluoresce in a way that indicates strain. Finally, a handheld infrared spectrometer is used to measure this fluorescence.
The advantage of strain paint over conventional strain gauges is that the gauge (the paint, in this case) and the read-out device don't have to be physically connected. Also, strain paint allows you to measure strain anywhere on the structure, and along any direction. This product is not yet on the market, but it will benefit all of us, as I'm sure we all find the structural integrity of our planes, bridges, and buildings to be pretty important.
Electricity from Viruses: Berkeley Lab scientists generate electricity using viruses.Courtesy Courtesy ksoScientists from the Berkeley Lab have developed a way to generate electricity from viruses! Their method is based on the piezoelectric properties of the virus, M13 bacteriophage. Piezoelectricity is the charge that accumulates in certain solids when a mechanical stress is applied to them (squeezing, pressing, pushing, tapping, etc.) The scientists realized that the M13 virus would be a great candidate for their research because it replicates extremely rapidly (no supply problems here), it’s harmless to humans (always a good thing), and it assembles itself into well-organized films (think chopsticks in a box). It was these films that they layered and sandwiched between gold-plated electrodes to create their nearly paper-thin generator. When this postage stamp-sized generator was tapped, it created enough electricity to flash a “1” on a liquid crystal screen.
The potential here is that someday we could put these super-thin generators in any number of places, and harness electricity by doing normal, everyday tasks like walking or closing doors. I propose putting them in the shoes of marathon runners and then have cell phone charging stations along the route. Nothing is more maddening than waiting all day in the rain to get an action shot of your runner, only to find that your battery has since died by the time your slow-poke reaches the finish line. There’s always next year.
World's smallest giraffe: Scanning electron microscopy (SEM) image depicting a baby giraffeCourtesy Image courtesy of the Materials Research Society Science as Art Competition and Shaahin Amini and Reza Abbaschian, University of California RiversideMaterials science is the study of the relationship between the structure of materials at the atomic or molecular scales and their properties at the macroscale. Materials scientists do a lot of monkeying around at super small scales, and the Materials Research Society (the organization that brings together materials scientists from academia, industry, and government) has given them a creative outlet. At each of their annual meetings, MRS includes a Science as Art competition, where any registered meeting attendee can enter an image they have created. The images are pretty amazing in their own right, but when you think about the methods, medium, and scale used to create them, it's truly mind-boggling! Here are some of the best entries from past meetings, and some video versions of selected works as well.
Smear campaign: climate scientist relates his own experience from anti-science attackCourtesy CECAR - Climate and Ecosystems Change Adaptation R (adapted by Mark Ryan)Several months back there was a lot of hoopla revolving around the so-called "Climategate" scandal. Climate scientists' emails were hacked, posted online and taken out of context as they were disseminated around the internet and through the news channels. Some researchers were charged with manipulating climate data to bolster their own point of view, and indignant investigations were launched against them. As the story fermented in the media, the blogosphere, and political circles, it grew into an over-inflated bag of hot-air. But, eventually, the truth prevailed, and those accused were exonerated by the facts. Michael Mann, a climate change researcher at Pennsylvania State University, was one of key figures in the "scandal", and has written (both here and in a new book) about his experience dealing with the kind of smear campaign that was hurled his way. He terms it the "scientization" of politics. It's involves some of same anti-science tactics used by the tobacco industry and creationists: mainly to cast doubt on the facts, and fabricate controversy where there is none.
This article describes the results of a study conducted by the Australian Government, which says some Australians “may be raising their risk of skin cancer by avoiding sunscreen due to unfounded fears over nanoparticles.” The article went on to say that one third of the people surveyed had heard or read about the possible risks of nanoparticles, and that 13% of these people would be less likely to use sunscreen. At first, this seemed like a very interesting finding – people would rank nanoparticles higher than skin cancer on their personal risk meters! But as I examined the article a little more, I realized I have a few issues with the way it presented the results. 
A Discrete Request for Regulation: The Hoff is on board.Courtesy Friends of the Earth Australia
First, the article makes it sound as if survey-takers were faced with the question, “would you rather risk getting skin cancer or use a sunscreen with nanoparticles in it?” In actuality, they were simply asked if they would be less likely to use a nanoparticle-based sunscreen, given the risks they’d heard about. I realize it is implied that if you don’t use sunscreen your chances of getting skin cancer increase, but when taking a survey, you’re probably just answering the question at hand: Would you be less likely to use a product that you’ve heard could by risky. These answers are also coming from a survey that repeatedly mentions the “possible risks of using sunscreen with nanoparticles” in various questions. It seems to me that hula hooping could start to sound risky by the end of a survey like that. “Have you heard or read about the possible risks of hula hooping? If you have heard or read about the possible risks of hula hooping, do the stories make you any less likely to hula hoop in general? Agree or Disagree: 1.) Hula hooping is risky to my health. 2.) Hula hooping is more risky to my health than not hula hooping 3.) I am scared to hula-hoop.” Ok, I exaggerate a little, but the way a survey is presented has an effect on the answers people provide.
I get that they’re trying to highlight the fact that some people perceive nanoparticle-based sunscreens as dangerous, and that’s an interesting finding- not because they would stop using sunscreen, but because the current weight of evidence suggests that the nanoparticles in sunscreens don’t penetrate the skin - they’re harmless to humans. Which brings me to my point that perhaps a more telling result of the study is the high number of people who said they didn’t know if nanoparticle-based sunscreens are risky, and needed more information before deciding whether to use them. The fact that some people perceive nanoparticle-based sunscreens as dangerous when the current scientific evidence suggests otherwise, supports the idea that people just don’t know enough about nanoparticle-based products.
Now, I’m not suggesting that all nanoparticle-based products are safe, across the board. I’m also not trying to downplay people’s concerns about this relatively new technology. In fact, I think a healthy dose of caution is a good thing when it comes to new technologies. I just think that fear comes from not knowing, and people’s concerns could be alleviated if they had more information. What is concerning is that the information isn’t exactly available. There are no regulations on nano products (though the FDA appears to be working on it), companies are not required to label their products as containing nanoparticles, and there are no standards in defining what a nano product is. What I am suggesting is that maybe we should be demanding that information from the likes of industries, governments, policy makers, etc, instead of focusing on the few that perceive nanoparticles as risky.
The point of the study was to figure out the public’s perception of sunscreens that contain nanoparticles, and I think it did. It showed that the public doesn’t know enough about it to make any real/informed decisions.
What’s your take? How do you feel about nanoparticles being used in products you rely on every day? What do you think about regulating this technology? Creating standards for it? Do you think these regulations and standards would stifle scientific progress, or protect our health? What do you think about hula hooping?
