Waxing Innovative: Researchers Pump Up Artificial Muscles Using Paraffin

Artificial muscles have mostly been flaccid as a replacement for motors. Could carbon nanotube yarns soaked in paraffin wax change this?


carbon nanotube,muscle,waxSPINNING A YARN: This scanning electron microscope image depicts a highly coiled, wax-filled carbon nanotube yarn that maximizes tensile contraction during actuation. Image: Courtesy of Science/AAAS

When Scientific American heard from chemist Ray Baughman a year ago, he and his international team of nanotechnologists had taken artificial-muscle technology to the next level. Their innovation relied on spinning lengths of carbon nanotubes into buff yarns whose twisting and untwisting mimicked natural muscles found in an elephant's trunk or a squid's tentacles.
?
Now the researchers are reporting a new artificial muscle?building technique that makes their carbon nanotube yarns several times faster and more powerful. These qualities could help deliver on the technology's promise of developing compact, lightweight actuators for robots, exoskeletons and other mechanical devices, although several challenges remain.
?
The latest breakthrough comes from infusing the carbon nanotube yarns with paraffin wax that expands when heated, enabling the artificial muscles to lift more than 100,000 times their own weight and generate 85 times more mechanical power during contraction than mammalian skeletal muscles of comparable size, according to the researchers, whose latest work is published in the November 16 issue of Science.
?
The previous-generation artificial muscles were electrochemical and functioned like a supercapacitor. When a charge was injected into the carbon nanotube yarn, ions from a liquid electrolyte diffused into the yarn, causing it to expand in volume and contract in length, says Baughman, director of the University of Texas at Dallas's Alan G. MacDiarmid NanoTech Institute. Unfortunately, using an electrolyte limited the temperature range in which the muscle could function. At colder temperatures the electrolyte would solidify, slowing down the muscle; if too hot, the electrolyte would degrade. It also needed a container, which added weight to the artificial-muscle system.
?
The wax eliminates the need for an electrolyte, making the artificial muscle lighter, stronger and more responsive. When heat or a light pulse is applied to a wax-impregnated yarn about 200 microns in diameter (roughly twice that of a human hair), the wax melts and expands. In about 25 milliseconds this expansion creates pressure causing the yarn's individual nanotube threads to twist and the yarn's length to contract. Any weightlifter will tell you that the success of any muscle?artificial or natural?depends in part on the degree of this contraction. Depending on the force exerted, the Baughman team's muscle strands could contract by up to 10 percent.
?
Muscles are also judged by the weight they can lift relative to their size. "Our muscles can lift about 200 times the weight of a similar-size natural muscle," Baughman says, adding that the wax-infused artificial muscles can also generate 30 times the maximum power of their electrolyte-powered predecessors.
?
The researchers' latest artificial muscles move the technology closer to commercialized products such as environmental sensors, aerospace materials and even textiles that take can take advantage of nanoscale actuators, University of Cincinnati mechanical engineering professor Mark Schulz, wrote in a related Science Perspectives article. This new artificial muscle outperforms existing ones, allowing possible applications such as linear and rotary motors; it also might replace biological muscle tissue if biocompatibility can be established, he adds.
?
However, Schulz points out?and Baughman is quick to acknowledge?that even this new crop of artificial muscles faces many challenges before they can be a practical alternative to mini?electric motors in many of the products we buy. Despite their improvements, the latest artificial muscles are for the most part inefficient and limited in the combinations of force, motion and speed they can generate, according to Schulz.
?
Indeed, these new artificial muscles operate at about 1 percent efficiency, a number Baughman and his colleagues want to increase at least 10-fold. An option for improving efficiency is to use a chemical fuel rather than electricity to power the muscles. "One way to compensate for a lack of efficiency is to use fuel like methanol instead of a battery," he says. "You could store more than 20 percent more energy in a fuel like methanol than you can in a battery."
?
Another challenge is that the artificial muscles must be heated and cooled to contract and release, respectively. Short lengths of yarn can cool on their own in a matter of seconds, but longer pieces would need to be actively cooled using water or air, otherwise the muscle would not relax. "Or you'd need [to use a] material that doesn't require thermal actuation," Baughman says. "If you keep making the [carbon nanotube] yarn longer and longer, your cooling rate increases."
?
This issue of scale poses perhaps the greatest challenge. A one-millimeter length of artificial muscle can lift about 50 grams, according to Baughman. That means lifting several tons would require a greater length of carbon nanotube yarn than is practical. "We'd like our artificial muscles to be used in exoskeletons that help workers or soldiers lift objects weighing tons," he says. But the researchers are still working out ways to pack enough yarn to perform such tasks into the length of an exoskeletal limb.
?
Carbon nanotube artificial muscles are more likely to first appear in products requiring only short lengths. Baughman envisions artificial muscles used in a catheter for minimally invasive surgery, "where you want to have lots of functionality on the end of the catheter to do surgical manipulations." Another application with flex appeal?"smart" fabrics that can automatically react to their environments, becoming more or less porous when they detect heat or harmful chemicals in the air.

Source: http://rss.sciam.com/click.phdo?i=f19f71a6df34d1d35739e9b62a5cb314

Jael Strauss Alison Pill gizmodo cnet britney spears sprint Sam Bacile

Mark Titus says government gave assurances for cooperation in ...

Mark Titus testified Wednesday morning that the federal government assured him it would not seize his property in exchange for his cooperation against River Birch Inc. executive Dominic Fazzio. Titus again cited a 2011 pre-sentencing report that said the government did not intend to seize or force him to forfeit his properties.

"I had it in writing from the government,'' Titus testified. "Why else would I think otherwise?''

The testimony came in U.S. District Court in New Orleans during a hearing on Fazzio's motion to dismiss an indictment against both men. Fazzio alleges that Titus, his brother-in-law and a co-defendant, had a secret deal with prosecutors to testify against him.

In his testimony, Titus also said he wore his own recording device when he secretly recorded a conversation with Fazzio in June 2011, as part of his cooperation with prosecutors. The testimony suggested the government was not aware that Titus was wearing his own device, but that prosecutors confiscated the device afterward.

Titus said prosecutors told him his device had not recorded anything.

His testimony continues Wednesday.


Source: http://www.nola.com/crime/index.ssf/2012/11/titus_government_gave_assuranc.html

Nick Foles Auguste Rodin Breaking Amish Indianapolis explosion jay cutler applebees jeff gordon

After Launching It In SF, eBay Brings Same Day Delivery Service To New York

eBay NowAfter launching its same day delivery service in San Francisco a few weeks ago, eBay is debuting 'eBay Now' to to New York City. Users in the area can download the new app here.

Source: http://feedproxy.google.com/~r/Techcrunch/~3/lg_yVYgKXh0/

dalai lama tamera mowry slow jam the news madden cover obama slow jams the news metta world peace ron artest

Rachael Ray shares her home recipes | MNN - Mother Nature Network

?

I usually bring cookbooks to your attention that have more of a local/seasonal/organic theme than Rachael Ray?s ?My Year in Meals? that released today, but when I was asked if I?d like a review copy of her latest cookbook, I said "yes" for a few reasons.

?

Earlier this year when the New York Times ran a piece about celebrity cookbooks being ghostwritten, Ray?s name was mentioned specifically. She defended herself on Twitter saying she?s proud to be the author of all her cookbooks. Then Bobby Flay said the following publically on ?Today? about Rachael Ray?s cookbooks.

?

I know for a fact that Rachael Ray writes her own recipes. I've seen her do it in between her shows, in the segments in a corner, writing her recipes away.

?

The fact that Flay singled Ray out during the controversy stayed with me and made me think that I should check out one of her cookbooks. When I learned that her newest cookbook would contain the recipes she cooked in her own home for friends and family over the course of a year, I thought, ?I want to have that cookbook.? So I accepted the review copy I was offered.

?

?My Year in Meals? is not a theme cookbook. The dishes are all over the place when it comes to types of cuisine, just like the dishes people cook at home are. Most of our home menus look like this - one night you cook spaghetti, the next morning you wake up and make eggs, and that evening you roast a chicken. That?s what Ray?s home meals look like, too, except she?s Rachael Ray so she makes Aglio e Olio with lemon flavored pasta, Baked Polenta with Eggs, and Poached Tarragon Creamed Chicken.

?

There?s a bonus with this book, too. Flip it over, and there are more than 100 cocktail recipes by Ray?s husband, John Cusimano. He seems like a very handy man to have around when entertaining. He shares his personal cocktail creations in the book, and there?s a nice variety of creative drinks.

?

?

The only thing I'd change about Ray's Buffalo Chicken Meatball recipe is the size of the meatballs. The recipe uses a pound of ground chicken for 16 meatballs. They would be fine if they were beef meatballs to serve with spaghetti, but I thought they were too big for appetizer portions. Next time, I?ll make 24 meatballs instead of 16 out of the mixture and adjust the cooking time appropriately.

?

I was speaking with some other food writers lately about how it?s almost impossible to get a cookbook deal these days unless you?re very specialized. For a new cook to get published, they need to specialize in something very specific like ?gluten-free, vegetarian overnight breakfast casseroles to be served on holidays that fall on even-numbered years.?

?

Fortunately, that?s not the case for someone like Rachael Ray. She can publish a book with a wide variety of foods that?s enjoyable to flip through and tag recipes that need to be made. They aren?t so different from what you usually make in your own kitchen, but they?re changed up just enough to make you want to try them. I think next I?ll be trying the White Coq au Vin.?

?

Source: http://www.mnn.com/food/recipes/blogs/rachael-ray-shares-her-home-recipes

Earthquake Costa Rica Clinton speech Michael Strahan Griselda Blanco Michelle Obama Speech eva longoria Rihanna

Montenegro train crash kills 2, injures 28

{ttle}

{cptn}","template_name":"ss_thmb_play_ttle","i18n":{"end_of_gallery_header":"End of Gallery","end_of_gallery_next":"View Again"},"metadata":{"pagination":"{firstVisible} - {lastVisible} of {numItems}","ult":{"spaceid":"84962389","sec":""}}},{"id": "hcm-carousel-1040283237", "dataManager": C.dmgr, "mediator": C.mdtr, "group_name":"hcm-carousel-1040283237", "track_item_selected":1,"tracking":{ "spaceid" : "84962389", "events" : { "click" : { "any" : { "yui-carousel-prev" : { "node" : "a", "data" : {"sec":"HCMOL on article right rail","slk":"prev","itc":"1" }, "bubbles" : true, "test": function(params){ var carousel = params.obj.getCarousel(); var pages = carousel._pages; // if same page, don't beacon if(("_ult_current_page" in carousel) && carousel._ult_current_page==pages.cur) return false; // keep track of current position within this closure carousel._ult_current_page = pages.cur; return true; } }, "yui-carousel-next" : { "node" : "a", "data" : {"sec":"HCMOL on article right rail","slk":"next","itc":"1" }, "bubbles" : true, "test": function(params){ var carousel = params.obj.getCarousel(); var pages = carousel._pages; // no more pages, don't beacon again // if same page, don't beacon if(("_ult_current_page" in carousel) && carousel._ult_current_page==pages.cur) return false; // keep track of current position within this closure carousel._ult_current_page = pages.cur; return true; } } } } } } })); }); Y.later(10, this, function() {(function() { try{ if (Math.floor(Math.random()*10) == 1) { var loc = window.location, decoded = decodeURI(loc.pathname), encoded = encodeURI(decoded), uri = loc.protocol + "//" + loc.host + encoded + ((loc.search.length > 0) ? loc.search + '&' : '?') + "_cacheable=1", xmlhttp; if (window.XMLHttpRequest) xmlhttp = new XMLHttpRequest(); else xmlhttp = new ActiveXObject("Microsoft.XMLHTTP"); xmlhttp.open("GET",uri,true); xmlhttp.send(); } }catch(e){} })(); }); Y.later(10, this, function() {Y.namespace("Media").ywaSettings = '"projectId": "10001256862979", "documentName": "", "documentGroup": "", "ywaColo" : "vscale3", "spaceId" : "84962389" ,"customFields" : { "12" : "classic", "13" : "story" }'; Y.Media.YWA.init(Y.namespace("Media").ywaSettings); }); Y.later(10, this, function() {if(document.onclick===YAHOO.Media.PreventDefaultHandler.newClick){document.onclick=YAHOO.Media.PreventDefaultHandler.oldClick;} }); }); });

Source: http://news.yahoo.com/montenegro-train-crash-kills-2-injures-28-195152718.html

jerry sandusky raul ibanez completely wrong Duck Dynasty hayden panettiere mila kunis stacey dash

Microsoft And Vodafone Group Among Most Active Stocks In ...

MINYANVILLE ORIGINAL The three most active funds and stocks in pre-market trading on the Nasdaq (INDEXNASDAQ:.IXIC) were Microsoft Corporation (NASDAQ:MSFT), Vodafone Group (NASDAQ:VOD), and PowerShares QQQ Trust (NASDAQ:QQQ) as of 9:00 a.m. EST.

Investors traded 5,532,306 shares of Microsoft, which was down $1.06, or 3.79%. Steve Sinofsky has left Microsoft. He headed the Windows unit and worked with Microsoft for 23 years. Julie Larson-Green will replace him and oversee all software and related hardware.

Investors exchanged 764,634 shares of Vodafone, which was down $0.95, or 3.60%. According to the New York Times, Vodafone wrote down the value of its network businesses in Spain and Italy by 5.9 billion British pounds, or $9.3 billion.

Investors also traded 286,734 shares of PowerShares QQQ Trust, which was down $0.43, or 0.68%.

(See also: Pre-Market Primer: Bonds Rally on Fiscal Cliff Worries.)

Twitter: @ChrisWitrak

The author has a position in Microsoft.

Source: http://www.minyanville.com/trading-and-investing/stocks/articles/stocks-trading-equities-investing-investments/11/13/2012/id/45788

doomsday clock nate robinson sharia law sharia law new hampshire primary results molly sims hostess brands

Hinesville PD to Hold Breast Cancer 5K - Fort Stewart, GA Patch

Breast Cancer 5K

The Hinesville Police Department is inviting the community to participate in the Gift of Giving to Life 5K Run/Walk Nov. 17. The event will benefit the Susan G. Komen for the Cure breast cancer organization.

Cost is $20 per person, or $15 per person in groups of four or more. Registration begins at 8 a.m., and the race starts at 8:30 a.m. For more information, call Officer James Williams at 912-368-8211.

Water Outage

There will be a water outage from 9 a.m. to 3 p.m. Wednesday on Fort Stewart to install a new backflow preventer. The outage will affect buildings 212, 213 and 215, and possibly 216 and 218.

For more information, contact Jim Shurling at 912-320-0472.

Orlando Resort Trip

Fort Stewart Leisure Travel will hold an Orlando resort trip Nov. 23-25. Join Leisure Travel for a trip to Worldgate Resort in Kissimmee, Fla. The resort features three outdoor pools, spa tubs, a fitness room, tennis and basketball courts and an arcade. There are free shuttles to SeaWorld, Disney World and Universal Studios.

Cost is $350 per room (1-4 people) and includes transportation to Orlando. There is a $50 charge for a fifth person. For more information, call 912-767-2841 or 912-315-3674.

?

?

?

Source: http://fortstewart.patch.com/articles/hinesville-pd-to-hold-breast-cancer-5k

cleveland browns minnesota twins bobby abreu 2012 draft colt mccoy arbor day mike adams

The energy of stunt kites

ScienceDaily (Nov. 12, 2012) ? It may seem as though the German plains are all but tapped out when it comes to wind energy production. To refute this theory researchers are sending stunt kites into the skies to harness the wind and convert the kinetic energy generated into electricity.

Kite surfing has risen to become a fashionable sporting activity, with the number of enthusiasts participating in this cross between wind surfing and stunt kite flying growing at a tremendous pace. When the wind catches the kite, the surfer is carried meters into the air; and the greater the leap, the bigger the thrill. But a modern stunt kite is capable of being much more than a mere piece of sporting equipment -- it has the potential to become a valuable energy producer. A stunt kite's aerial movements can be used to drive a generator, which in turn converts this kinetic energy into electricity. This dynamic idea came to the founders of Berlin-based wind energy developer NTS GmbH. To make their concept a reality, they brought in the Fraunhofer Institute for Manufacturing Engineering and Automation IPA in Stuttgart. The project partners intend to use their new method to harness the power of strong winds at altitudes of up to 500 meters.

Joachim Montnacher, an engineer at the IPA, explains how a "kite power station" works thus: "The kites fly at a height of 300 to 500 meters, perfectly positioned to be caught by strong winds. Cables, about 700 meters in length, tether the kites to vehicles and pull them around a circuit on rails. A generator then converts the kinetic energy of the vehicles into electricity. The control and measuring technology is positioned on the vehicles." Compared to conventional wind farm technology that relies on rotors, this technology offers a wide range of advantages. Wind speeds at ground level tend to zero, but they increase dramatically the higher you go. At a height of 100 meters wind speeds are around 15 meters a second; at 500 meters they exceed 20 meters a second. "The energy yield of a kite far exceeds that of a wind turbine, whose rotor tips turn at a maximum height of 200 meters. Doubling the wind speed results in eight times the energy," says Montnacher. "Depending on wind conditions, eight kites with a combined surface area of up to 300 square meters can equate to 20 conventional 1-megawatt wind turbines."

More consistent winds at 500 meters

Kites do not have to struggle with the constancy of the wind the way turbines do, because the higher you go, the windier things get. Figures for the past year show that at a height of 10 meters, there is only about a 35 percent chance of wind speeds reaching 5 meters a second, but at 500 meters that likelihood goes up to 70 percent. This makes any number of new lowland sites viable for the production of wind energy. Another advantage is that it costs considerably less to build a system that, among other things, does not require towers each weighing hundreds of tons.

The project partners have clearly divided up responsibilities: NTS GmbH will design the kites and construct the high-altitude wind farm, and the researchers from the IPA will be in charge of developing the control and measuring technology, which includes the cable winching mechanism and cable store. One of the jobs of the control unit is to transmit the measuring signals to the cable control and kite regulation mechanisms. A horizontal and vertical angle sensor located in each cable line and a force sensor within the cable distributor guarantee precise control of the kite's movements as it follows either a figure-of-eight or sine-wave flight path up above. These flight maneuvers generate a high pulling power of up to 10 kilonewtons (kN) -- meaning that a 20-square-meter kite has the capacity to pull one ton. Each vehicle is pulled by a different flight system.

At a test site in Mecklenburg-West Pomerania, IPA researchers and NTS GmbH have already been able to send a kite on its maiden voyage along a 400-meter-long straight track. A remote control similar to those used to fly model planes was used to manually control the kite. The experts now want to reconfigure the test track making it into a loop. Computers will eventually be used to achieve fully automatic control of the kites.

"According to our simulations, we could use an NTS track running a total of 24 kites to generate 120 gigawatt hours a year (GWh/year). To put this into perspective, a 2-megawatt wind turbine produces around 4 GWh/year. So an NTS system could replace 30 2-megawatt turbines and supply power to around 30,000 homes," says Guido L?tsch, managing director of NTS GmbH. After successful test flights on the demonstration track, the project partners are confident that their computer simulations will hold up in reality. The first investors are already on board.

Share this story on Facebook, Twitter, and Google:

Other social bookmarking and sharing tools:


Story Source:

The above story is reprinted from materials provided by Fraunhofer-Gesellschaft.

Note: Materials may be edited for content and length. For further information, please contact the source cited above.


Note: If no author is given, the source is cited instead.

Disclaimer: Views expressed in this article do not necessarily reflect those of ScienceDaily or its staff.

Source: http://feeds.sciencedaily.com/~r/sciencedaily/most_popular/~3/I9yUfqMOg-s/121112090515.htm

Movember USC shooting halloween camilla belle chipotle lsu football lsu football