Stories tagged nanoscience

May
22
2014

Scientists at University of California Berkeley have been able to use carbon nanotbues to create light activated "smart curtains" that respond automatically to light without batteries. The curtain material can bend or straighten in response to the flick of a light switch.

To create the smart curtain, carbon nanotubes are layered onto a plastic polycarbonate membrane. The carbon nanotubes absorb light, convert the light into heat, and then transfer the heat to the plastic membrane surface. The plastic responds to the heat by expanding, but the carbon nanotubes do not, causing the two-layered material to bend blocking the light.

To read more about this research visit:
https://newscenter.berkeley.edu/2014/01/09/smart-curtains/

Diagrams of Smart Curtains:
http://www.nature.com/ncomms/2014/140107/ncomms3983/fig_tab/ncomms3983_F...

Link to Smart Curtains YouTube video:

See video

To learn more about nanotechnology, science, and engineering, visit:
www.whatisnano.org

To see other nano stories on Science Buzz tagged #nano visit:
http://www.sciencebuzz.org/buzz_tags/nano

Nov
08
2011

Professor Richard Handy and his team of scientists at Plymouth University in the UK have discovered that nanoparticles of titanium dioxide are causing holes to form (you can call them vacuoles if you want to be fancy), and nerve cells to die, in the brains of living fish. Titanium Dioxide
Titanium DioxideCourtesy Wikimedia Commons

“Gee, that sounds bad,” you might think. “But what does that have to do with me? I can’t say I’ve ever purchased a box of titanium dioxide at the grocery store.” Nope, you haven’t. But what you have purchased at the grocery store is food with titanium dioxide in it (to make your white foods whiter), and you’ve also purchased some makeup and sunblocks made with nanoparticles of titanium dioxide. And you ate your Angel Food Cake. Or you washed the makeup off your face. Or showered after a protected day in the sun. The concern is that those titanium dioxide nanoparticles could make their way through our wastewater treatment systems and ultimately end up in our rivers and streams. And cause holey fish brains.Rainbow Trout
Rainbow TroutCourtesy Timothy Knepp - U.S. Fish and Wildlife Service

In all honesty, it’s less likely that your personal usage will be directly responsible for holey fish brains and more likely that the problem rests with the large-scale manufacturing process of these products…but you’re still a key component because you’re buying what they’re selling. And so they’re making more. And now that we’ve discovered holey fish brains as a result of exposure to an ingredient in products we’re using – what should we do? Heck, holey fish brains should be concerning enough in and of itself – but let’s just take this one step further: If that’s what happens to fish, what might happen to humans?

Luckily, some important questions and conversations have arisen in the public sphere – let’s just hope the decision-makers are listening. From Nanowerk:

“The results of Professor Handy's work and that of other researchers investigating the biological effects of nanoparticles may influence policy regulations on the environmental protection and human safety of nanomaterials.

“‘It is worrying that the effects on the fish brain caused by these nanoparticles have some parallels with other substances like mercury poisoning, and one concern is that the materials may bioaccumulate and present a progressive or persistent hazard to wildlife and to humans,’ says Professor Handy.”

A writer over at Frogheart
posed some thoughtful questions, too:

  • The statement is that nanoparticles cause brain injury in fish but the researchers mention titanium di/oxide nanoparticles only. Did they test other nanoparticles as well?
  • How did they conduct the tests?
  • Did the fish ingest titanium di/oxide from the water? From their food? From both?
  • What concentrations were they exposed to?
  • Were they in an environment similar to what they’d experience naturally? Or were they in special tanks?

Good news, frogheart! Professor Handy and his team aren’t the only scientists doing this kind of research involving nanoparticles in the environment. Duke University’s Center for the Environmental Implications of NanoTechnology (CEINT) have recently shared their work on nanosilver in the environment with NISE Net, who in turn made a fascinating 6-minute video to make it all make sense:

Does Every Silver Lining Have a Cloud? from NISE Network on Vimeo.

And I happened to sit in on a panel discussion this very morning about Nanomaterials, Toxicology, and Risk, where Shannon Hanna of the University of California Santa Barbara’s Center for Nanotechnology in Society (CNS UCSB) gave a fascinating presentation about “Impacts of Zinc Oxide Nanoparticles on the Mussel.” In it, he and his team found that chronic exposure to zinc oxide had a negative impact on growth and survival on the Mediterranean Mussel.Mediterranen Mussel
Mediterranen MusselCourtesy uncredited
Nanoparticles of zinc oxide are in a whole slew of products, including the paint on boats. Boats which tend to congregate near docks. Where mussels also like to congregate. And it turns out mussels are basically Filters of the Ocean. They accumulate metals and pollutants. And then pretty much every other thing in the ocean and around the ocean (birds, us) like to eat them. Add too much zinc oxide to the mix? Runty and short-lived mussels. Hmmmm. Anyone hungry?

The studies seem to be piling up, and it’s increasingly apparent to me that nanoparticles and environment don’t play nice. Perhaps its time to start talking seriously about regulation? What do you think?

Jun
02
2011

Some ultra-warm, yet ultra-cool company, called Nanoayegh, makes “nanotechnology insulation” (ultra-warm/ultra-cool/insulation – get it? GET IT?) Anyway, the unpronounceable Nanoayegh has a super-sweet zooming device that allows you to Coffee bean = sooooooooo big!
Coffee bean = sooooooooo big!Courtesy Jeff Kubina
zoom in and out between a coffee bean and a single carbon atom. On the journey between the two, you’ll pass such earthly delights HIV virus = soooooooo small!
HIV virus = soooooooo small!Courtesy Wikimedia Commons
as a human skin cell, E. Coli bacterium, and the HIV virus.

So that was kind of awesome, right? But why should you care about stuff that small? Well, in a nutshell, because it’s really important and will change the world we live in. No small peanuts, right? Swing on over to www.whatisnano.org for all sorts of cool nano-related videos and photos that make it all make sense; ‘cause there’s nothing like a blue human to put it all into perspective.

WHAT ARE YOU STILL DOING HERE? Go play a little! (nano/little – get it? GET IT?)

May
10
2011

Sometimes we here at Nano Headquarters grow weary of reading and attempting to decipher scientific papers in ways that make them easy to understand.

Take, for example, this sentence:

“The as-prepared gold particles showed good catalytic activity for the reduction of 4-nitrophenol to 4-aminophenol by excess NaBH4, and a surface-enhanced Raman scattering (SERS) study suggested that the gold nanoparticles exhibited a high SERS effect on the probe molecule Rhodamine 6G.”

Here’s what we were able to immediately comprehend:

“The as-prepared gold particles showed good BEEEEEEEP for the reduction of BEEEEEEEP to BEEEEEEEP by excess BEEEEEEEP, and a surface-enhanced BEEEEEEEP BEEEEEEEP BEEEEEEEP study suggested that the gold nanoparticles exhibited a high BEEEEEEEP effect on the probe molecule BEEEEEEEP BEEEEEEEP”

On days like this, we like to practice what we call "selective avoidance" and seek out pretty images instead. Pretty nano-related images, mind you – but pretty images nonetheless. They soothe our bleeding brains. And so, for your BEEEEEEEP-free pleasure, we offer you this here compendium of pretty nano images:

Pretty!: Pollen Grains
Pretty!: Pollen GrainsCourtesy Dartmouth Electron Microscope Facility

NOVA - The Art of Nanotech
Remember our friends over at NOVA who made the nanorrific Making Stuff series? This here slideshow was a little buried treasure accompanying it. The images are originally from the Materials Research Society - Science as Art competition. We’re a little partial to the Starry Night knockoff. Van Gogh would be impressed. And if not, then we wouldn’t have wanted to be his friend anyway because apathy gets boring fast and huffy, stuffy artists are tedious.

Sciencescapes Speaking of the Science as Art competition – here are a few more images from competitions in years past. From likenesses of spaghetti and meatballs to a decaying Santa to a creepy Pac-Man to a dotted-dude walking off a cliff to his ultimate doom, there’s a little something here for everyone.
Also Pretty!: Water Droplet on Nasturtium Leaf
Also Pretty!: Water Droplet on Nasturtium LeafCourtesy Stephan Herminghaus

International Science and Engineering Visualization Challenge
A video from the National Science Foundation wherein they invite us to “discover the artistry behind the 2010 International Science & Engineering Visualization Challenge winners as they explain the processes, techniques and thoughts behind their entries.” SPOILER ALERT: The very first fellow we meet tells us right out that there’s “no message” to his work. Awesome.

Silver Saver – nanotech in art preservation Think that the old, old artifacts you see in museums just stay that way because they’re in a fancy, climate-controlled case? Think again!
Equally Pretty!: Silicon Nanomembrane
Equally Pretty!: Silicon NanomembraneCourtesy S. Scott, University of Wisconsin-Madison

NISE Net Viz Lab All the pretty, pretty pictures you’ve seen in this post thus far are from the NISE Net Viz Lab. And guess what? They’re in the public domain! That means you can use them however you like without going through all sorts of crazy legal hoops! Whee! Just remember to give credit where credit it due – ‘cause we’re pretty sure you don’t have a scanning electron microscope at home.

SPECIAL NOT-NECESSARILY-NANO BONUS:
The Periodic Table Printmaking Project We could look at these for DAYS. In fact, we have. Take the Periodic Table of the elements, mix in a few block-print makers, and what do you get? Some seriously killer prints that provide visual intrigue for such favorites as Promethium and Fluorine. We will admit to getting a little googley-eyed over these.

Okay kids, stop swooning. Back to work.

Nov
02
2007

Nanotechnology sometimes borrows from nature.

Morpho butterfly: Pigments don’t cause these butterflies’ intense colors. Instead, super-small lattice-like structures on the wings reflect only certain wavelengths of light (or color). And the colors shift with your perspective. (Photo courtesy Lionoche, through Flickr)
Morpho butterfly: Pigments don’t cause these butterflies’ intense colors. Instead, super-small lattice-like structures on the wings reflect only certain wavelengths of light (or color). And the colors shift with your perspective. (Photo courtesy Lionoche, through Flickr)

Super-small, light-reflecting structures—instead of pigments—create a morpho butterfly's intense, iridescent wing color. Scientists are developing nanomaterials with similar properties.

Zoom in on a butterfly's wing
Zoom in on a butterfly's wing

If you used a special microscope to look at these butterfly wings, you’d see tiny scales made up of thin layers of transparent wing material with nanoscale gaps between them. Light waves bouncing off the bottom surfaces interfere with waves reflecting from the tops. Most light waves are cancelled and only certain wavelengths—or colors—bounce back to your eyes. The more light in the environment, the brighter the color.

Wing structures: These complicated structures on butterfly wings manipulate light to control the color that we see.
Wing structures: These complicated structures on butterfly wings manipulate light to control the color that we see.

How do transparent thin films create color?: Scientists haven't yet created materials that work exactly like the butterfly wings. But layers and layers of transparent, super-thin films--each with a different index of refraction--can be tuned so that they only reflect specific wavelengths of light (o
How do transparent thin films create color?: Scientists haven't yet created materials that work exactly like the butterfly wings. But layers and layers of transparent, super-thin films--each with a different index of refraction--can be tuned so that they only reflect specific wavelengths of light (o

Scientists are developing all sorts of products that, like the butterfly wings, use layers of transparent materials with nanoscale spacing between them to manipulate light and create color. With them, we can create computer and cell phone displays, fabrics and paints that change color, optical devices that improve telecommunications systems, and films that reflect much more light than glass mirrors. Can you imagine other uses?