How graphene and friends could harness the Sun's energy hitting walls

May 1, 2013 ? Combining wonder material graphene with other stunning one-atom thick materials could create the next generation of solar cells and optoelectronic devices, scientists have revealed.

University of Manchester and National University of Singapore researchers have shown how building multi-layered heterostructures in a three-dimensional stack can produce an exciting physical phenomenon exploring new electronic devices.

The breakthrough, published in Science, could lead to electric energy that runs entire buildings generated by sunlight absorbed by its exposed walls; the energy can be used at will to change the transparency and reflectivity of fixtures and windows depending on environmental conditions, such as temperature and brightness.

The isolation of graphene, by University of Manchester Nobel Laureates Professor Andre Geim and Professor Kostya Novoselov in 2004, led to the discovery of the whole new family of one-atom-thick materials.

Graphene is the world's thinnest, strongest and most conductive material, and has the potential to revolutionise a huge number of diverse applications; from smartphones and ultrafast broadband to drug delivery and computer chips. The isolation of graphene also led to the discovery of a whole new family of one-atom-thick materials.

Collectively, such 2D crystals demonstrate a vast range of superlative properties: from conductive to insulating, from opaque to transparent. Every new layer in these stacks adds exciting new functions, so the heterostructures are ideal for creating novel, multifunctional devices.

One plus one is greater than two -- the combinations of 2D crystals allow researchers to achieve functionality not available from any of the individual materials.

The Manchester and Singapore researchers expanded the functionality of these heterostructures to optoelectronics and photonics. By combining graphene with monolayers of transition metal dichalcogenides (TMDC), the researchers were able to created extremely sensitive and efficient photovoltaic devices. Such devices could potentially be used as ultrasensitive photodetectors or very efficient solar cells.

In these devices, layers of TMDC were sandwiched between two layers of graphene, combining the exciting properties of both 2D crystals. TMDC layers act as very efficient light absorbers and graphene as a transparent conductive layer. This allows for further integration of such photovoltaic devices into more complex, more multifunctional heterostructures.

Professor Novoselov said: "We are excited about the new physics and new opportunities which are brought to us by heterostructures based on 2D atomic crystals. The library of available 2D crystals is already quite rich, covering a large parameter space.

"Such photoactive heterostructures add yet new possibilities, and pave the road for new types of experiments. As we create more and more complex heterostructures, so the functionalities of the devices will become richer, entering the realm of multifunctional devices."

University of Manchester researcher and lead author Dr Liam Britnell added: "It was impressive how quickly we passed from the idea of such photosensitive heterostructures to the working device. It worked practically from the very beginning and even the most unoptimised structures showed very respectable characteristics"

Professor Antonio Castro Neto, Director of the Graphene Research Centre at the National University of Singapore added: "We were able to identify the ideal combination of materials: very photosensitive TMDC and optically transparent and conductive graphene, which collectively create a very efficient photovoltaic device.

"We are sure that as we research more into the area of 2D atomic crystals we will be able to identify more of such complimentary materials and create more complex heterostructures with multiple functionalities. This is really an open field and we will explore it."

Dr Cinzia Casiraghi, from The University of Manchester, added: "Photosensitive heterostructures would open a way for other heterostructures with new functionalities. Also, in future we plan for cheaper and more efficient heterostructure for photovoltaic applications."

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The above story is reprinted from materials provided by Manchester University, via AlphaGalileo.

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

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Journal Reference:

1. L. Britnell, R. M. Ribeiro, A. Eckmann, R. Jalil, B. D. Belle, A. Mishchenko, Y.-J. Kim, R. V. Gorbachev, T. Georgiou, S. V. Morozov, A. N. Grigorenko, A. K. Geim, C. Casiraghi, A. H. Castro Neto, and K. S. Novoselov. Strong Light-Matter Interactions in Heterostructures of Atomically Thin Films. Science, 2 May 2013 DOI: 10.1126/science.1235547

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/N8nsPsaCo7U/130502142506.htm

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Immigration debate gives life to annual rallies

Alma Banuelos, left, with Emilia Hernandez shout slogans during a rally in downtown Los Angeles Wednesday, May 1, 2013. In celebration of May Day thousands have gathered for an immigration reform rally in downtown Los Angeles. (AP Photo/Nick Ut)

Alma Banuelos, left, with Emilia Hernandez shout slogans during a rally in downtown Los Angeles Wednesday, May 1, 2013. In celebration of May Day thousands have gathered for an immigration reform rally in downtown Los Angeles. (AP Photo/Nick Ut)

Thousands of people march during a May Day rally in downtown Los Angeles on Wednesday, May 1, 2013. In celebration of May Day, people have gathered across the country to rally for various topics including immigration reform. (AP Photo/Damian Dovarganes)

Thousands of people march during a May Day rally in downtown Los Angeles on Wednesday, May 1, 2013. In celebration of May Day, people have gathered across the country to rally for various topics including immigration reform. (AP Photo/Damian Dovarganes)

Thousands of people march during a May Day rally in downtown Los Angeles on Wednesday, May 1, 2013. In celebration of May Day, people have gathered across the country to rally for various topics including immigration reform. (AP Photo/Damian Dovarganes)

Oregon Gov. John Kitzhaber waits for his introduction at a May Day rally during which he went on to sign Senate Bill 833 into law on the steps of the State Capitol in Salem, Ore. on Wednesday, May 1, 2013. The bill authorizes driver's cards for those without the documents to obtain regular driver's licenses. (AP Photo/The Oregonian, Beth Nakamura)

LOS ANGELES (AP) ? Demonstrators demanded an overhaul of immigration laws Wednesday in an annual, nationwide ritual that carried a special sense of urgency as Congress considers sweeping legislation that would bring many of the estimated 11 million people living in the U.S. illegally out of the shadows.

Thousands joined May Day rallies from Concord, N.H., to Los Angeles, where scores of marchers gathered downtown. In Salem, Ore., Gov. John Kitzhaber was cheered by about 2,000 people on the Capitol steps as he signed a bill to allow people living in Oregon without proof of legal status to obtain drivers licenses.

In Vermont, more than 1,000 people assembled on the Montpelier Statehouse lawn. And in New York, paper rats on sticks bobbed along Sixth Avenue as about 200 protesters set off from Bryant Park, chanting: "What do we want? Justice! When do we want it? Now!" The rats were intended to symbolize abused migrant workers.

The May Day crowds paled in comparison to the massive demonstrations of 2006 and 2007, during the last serious attempt to introduce major changes to the U.S. immigration system. Despite the large turnouts six years ago, many advocates of looser immigration laws felt they were outmaneuvered by opponents who flooded congressional offices with phone calls and faxes at the behest of conservative talk-radio hosts.

Now, immigrant advocacy groups are focusing heavily on calling and writing members of Congress, using social media and other technology to target specific lawmakers. Reform Immigration for America, a network of groups, claims more than 1.2 million subscribers, including recipients of text messages and Facebook followers.

Many of Wednesday's rallies featured speakers with a personal stake in the debate. Naykary Silva, a 26-year-old Mexican woman in the country illegally, joined about 200 people who marched in Denver's spring snow, hoping for legislation that would ensure medical care for her 3-year-old autistic son.

"If you want to do something, you do it no matter what," Silva said. "There's still more work to do."

Police in New York restrained several demonstrators, but the marches were peaceful. In downtown Seattle, dozens gathered under heavy police presence, one year after some protesters broke windows and set fires.

Gabriel Villalobos, a Spanish-language talk radio host in Phoenix, said many of his callers believe it is the wrong time for marches, fearful that that any unrest could sour public opinion on immigration reform. Those callers advocate instead for a low-key approach of calling members of Congress.

"The mood is much calmer," said Villalobos, who thinks the marches are still an important show of political force.

In Los Angeles, a band playing salsa classics from the back of a truck led a march up Broadway.

"I've held the same job for six years, but I don't have papers," said Mario Vasquez, a supermarket butcher who brought his two Chihuahuas. "Immigration reform would help me and my family and for everybody here."

May Day rallies began in the United States in 2000 during a labor dispute with a restaurant in Los Angeles that drew several hundred demonstrators, said Angelica Salas, executive director of the Coalition for Humane Immigrant Rights of Los Angeles. Crowds grew each year until the House of Representatives passed a tough bill against illegal immigration, sparking a wave of enormous, angry protests from coast to coast in 2006.

The rallies, which coincide with Labor Day in many countries outside the U.S., often have big showings from labor leaders and elected officials.

Demonstrators marched in countries around the world, with fury in Europe over austerity measures and rage in Asia over relentlessly low pay, the rising cost of living and hideous working conditions that have left hundreds dead in recent months alone.

The New York crowd was a varied bunch of labor groups, immigrant activists and demonstrators unaffiliated with any specific cause. Among them was 26-year-old Becky Wartell, who was carrying a tall puppet of the Statue of Liberty.

"Every May Day, more groups that have historically considered themselves separate from one another come together," she said.

In Brea, a Los Angeles suburb, a small group opposed to the legislation stood on a freeway bridge waving signs at motorists. One read, "No Amnesty."

___

Spagat reported from San Diego. Associated Press writers contributing to this report include Meghan Barr in New York, Morgan True in Concord, N.H., Lauren Gambino in Salem, Ore., Gene Johnson in Seattle and Alexandra Tilsley in Denver.

Associated Press

Source: http://hosted2.ap.org/APDEFAULT/495d344a0d10421e9baa8ee77029cfbd/Article_2013-05-01-Immigration%20Marches/id-b968f2807138491eb5b42696ced59b2c

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Samsung starts production of 20nm 4Gb LPDDR3 mobile DRAM

What is it that you want to know about the RAM in your mobile device? Usually, how much of it there is, and if you're a little more demanding of your hardware, maybe what type it is, too. Well, folk in the latter category might interested to know that Samsung has started production of 20nm 4Gb LPDDR3 mobile DRAM. As is the nature of smaller, more efficient components, the new chips promise to be faster (2,133 Mbps per pin, over LPDDR2's 800 Mbps), and -- so claims Samsung -- a 20 percent drop in power consumption. With just four of these new chips, OEMs can have a 2GB offering that's still just a slick 0.8mm in height.

Filed under: Cellphones, Tablets, Mobile

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Source: http://feeds.engadget.com/~r/weblogsinc/engadget/~3/UIW7l481Ysw/

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Hasselblad stops production of V System cameras after 17 years

Almost by definition, Hasselblad is a company steeped in tradition -- it's hard to be ultra-trendy when your camera systems cost as much as a new car. We shouldn't be surprised, then, that the company is only just getting around to halting production on its last V System camera, the 503CW, 17 years after the first models rolled off the assembly line. Interest has simply dropped off quickly in the past five years, the company says. Support will continue, and accessories will sell while they last, but the emphasis from now on will be squarely on digital-first H System cameras like the H5D. Whether or not you're mourning the loss, there's no question that the V System has survived a lot during its lifetime, including the transition to digital shooting and new management. We'd say it's worth pouring one out for a true veteran of medium format photography.

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Source: Hasselblad (1), (2)

Source: http://feeds.engadget.com/~r/weblogsinc/engadget/~3/1k2jCJ5qBQE/

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Marriage Proposal Ad: Guy Pops Question With Full-Page Newspaper "Story"!

Source: http://www.thehollywoodgossip.com/2013/05/marriage-proposal-ad-guy-pops-question-with-full-page-newspaper/

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Hunting, NYC style: Owners set dogs on alley rats

NEW YORK (AP) ? Bodies tensed and noses twitching, the dogs sniff the hunting ground before them: a lower Manhattan alley, grimy, dim and perfect for rats. With a terse command ? "Now!" ? the chase is on.

Circling, bounding over and pawing at a mound of garbage bags, the four dogs quickly have rodents on the run.

"Come on ... I mean, 'tally ho!' says one of their owners, Susan Friedenberg. In a whirl of barks, pants and wagging tails, dogs tunnel among the bags and bolt down the alley as their quarry tries to scurry away.

Within five minutes, the city has two fewer rats.

In a scrappy, streetwise cousin of mannerly countryside fox hunts, on terrain far from the European farms and fields where many of the dogs' ancestors were bred to scramble after vermin and foxes, their masters sport trash-poking sticks instead of riding crops and say it's just as viable an exercise for the animals' centuries-old skills.

"It's about maintaining the breed type through actual work," says Richard Reynolds, a New Jersey-based business analyst and longtime dog breeder who might be considered the group's organizer ? if it would accept being called organized.

Known with a chuckle as the Ryders Alley Trencher-fed Society ? parse the acronym ? the rodent-hunters have been scouring downtown byways for more than a decade, meeting weekly when weather allows.

On a couple of recent nights, an eclectic group of ratters converged on an alley near City Hall about an hour after sunset. The lineups included two border terriers; a wire-haired dachshund; a Jack Russell terrier/Australian cattle dog mix; a Patterdale terrier, an intense, no-nonsense breed that's uncommon in this country; and a feist, a type of dog developed in the American South to tree squirrels.

"Get 'im! Go!" Serge Lozach yelled as his cairn terrier, Hudson, streaked down an alley after a fleeing rat. Unlike many of the other owners, Lozach doesn't breed or show dogs, but he has taken Hudson to several alley hunts.

"I like watching him have fun," Lozach said.

Although the dogs have hunting instincts, it takes training to capitalize on them. Just because your pet runs after backyard squirrels doesn't mean it could ever catch one.

When at its best, the alley pack works together. One dog will sniff out a rat and signal its whereabouts, often by barking. Another leaps at the hideaway to rout the quarry, and then a third lurches to catch it as it flees. A rat that scuttles into the open might get caught in a rundown, or even a tug of war, between dogs that circle and flank it.

After making a kill with a bite or a shake, the hunters trot back, rat in mouth, and allow their owners to take it from their jaws. The night's kill ends up in a trash bin.

There's no official estimate of how many rats rove the city's streets, basements, parks and subways. But there are plenty.

Officials have tried a number of innovative tactics to rout them, including a 2007 city Health Department initiative that sent inspectors with hand-held computers to map infestations in a Bronx neighborhood and then followed up with owners to address the problems.

Recently, the Metropolitan Transportation Authority agreed to let an Arizona-based company test a form of rat birth control by setting out bait in some subway stations this summer.

But the terrier forays are an unofficial undertaking, and participants say they're less about killing rats than giving dogs the experience of chasing them. The Health Department declined to comment on the hunts.

The idea has a long history. A noted 1851 examination of working-class life in London describes rat-catchers working the city's streets with ferrets and terriers. More recently, a rat-catching dachshund got attention in Seattle when its owner happened by while City Councilman Tom Rasmussen was checking out a downtown cleanup program in 2010. Rasmussen snapped a picture of the dog, rat in mouth, and posted the photo on his website.

There's even an American dog breed called a rat terrier, though its origins lie on farms.

Rat-tracking recently became an official canine sport, called "barn hunt." Dogs get two minutes to sniff around a hay-bale maze and indicate where they smell a rat concealed in a crush-proof, aerated tube; the dog never catches the quarry. Dozens of dogs competed in the first trials this past month in Columbia, Mo.

While dog owners may see it as time-honored pursuit, rat-hunting riles animal-rights advocates. People for the Ethical Treatment of Animals, which opposes hunting in general, expressed outrage after video of a dog snatching rats in a New York City park surfaced online two years ago. PETA Spokesman Martin Mersereau calls the alley rat quests "a twisted blood sport masquerading as rodent control."

Reynolds counters that "there are lots of worse things that people do to rats," noting that poisons can sicken the animals for hours.

As for the dogs, they have sometimes gotten stuck in waste bins or tumbled into holes, and a recent night left two with scrapes. But Reynolds says none has ever been seriously hurt or fallen ill.

In one recent foray, the dogs dispatched 13 rats within about a half-hour.

The dogs prowled and prodded for about 90 more minutes before the group gave up for the night. But not to worry, said dachshund owner Trudy Kawami.

"There will always be a million rats in the naked city."

___

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Source: http://news.yahoo.com/hunting-nyc-style-owners-set-dogs-alley-rats-062823011.html

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Visitors help Boston shops bounce back after Marathon attacks

By Ross Kerber

BOSTON (Reuters) - One tourist wanted to eat at a restaurant as close to the Boston Marathon finish line as possible. Other well-wishers made a point of buying shoes at the running store just a few steps away from a bomb blast site.

With their dining and shopping dollars, throngs of visitors to Boston's Boylston Street are helping small businesses recover quickly from millions of dollars in losses after the Boston Marathon bombing attacks on April 15.

"The support has been incredible," said Colin Peddie, owner of Marathon Sports, of the customers who have flooded his running goods store close to the racecourse finish - and the site of the first of two blasts that killed three people and injured 264.

Unlike the September 11, 2001 attacks, the last comparable event on U.S. soil, the low-tech bombing of the Boston Marathon left relatively little property damage.

Still, a number of businesses in the area were forced to temporarily close to repair minor damage or wait for police to complete their investigation of crime scene.

Meg Mainzer-Cohen, president of the 500-member local Back Bay Association trade group, said about half of them lost at least some money due to the bombings and their aftermath. She estimated losses total tens of millions of dollars.

Many retailers and restaurants now hope to make up their losses through increased foot traffic from visitors, runners and locals coming to the site of the attacks, she said.

At Marathon Sports, where the blasts blew apart the shopfront, Peddie credited his local insurer with helping him reopen quickly and said the store is on track to recoup the losses as visitors return to the area.

"It's for all the wrong reasons, but for now when someone comes to Boston they're going to take that walk down Boylston Street," Peddie said.

Mark Shapiro, a doctor who had just arrived from San Diego on Friday and was taking pictures outside a packed Marathon Sports, said he and his wife made it one of their first stops.

"We both agreed we wanted to pay our respects, but it was nothing like I expected. I had no idea it would be so crowded," Shapiro said.

Representatives for several investment fund companies and other professional businesses in the area said most employees were able to work remotely during the days much of the area was closed off as a crime scene - including during a citywide shutdown on April 19 as police searched for one of the bombing suspects.

These included International Data Group, the technology research firm whose headquarters are in an office building just next to the site of the first blast.

SEEKING RESTAURANT NEAR FINISH LINE

Some retailers and businesses were less fortunate.

At The Tannery, a fashionable footwear and clothing store at the corner of Boylston and Exeter streets, general manager Gerardo Defabritiis estimated lost sales of more than $100,000 for his store, which has 15 employees.

"We're talking about six figures," he said. Still, only one window was slightly damaged in the attacks and nobody was injured, he said. "We're OK, thank God," he said.

Those likely to wind up hit hardest are doctors, hair salons and other service providers who charge by the visit and cannot easily make up sales such as by staying open later, said Mainzer-Cohen of the Back Bay Association.

"There are only so many hours in the day," she said.

The U.S. Small Business Administration said on Monday it would make available low-interest disaster loans of up to $2 million to help those impacted by the attack. Not all business-interruption insurance covers losses tied to terror attacks.

Mike Ross, a Boston city councilman whose district includes the area, said he has gotten a flood of contacts from out-of-town visitors looking to stop in after the attacks. One man from New York, Ross said, e-mailed for help finding a restaurant as close to the Boston Marathon's finish line as possible.

"We're really pumped," Ross said of visitors' new enthusiasm for the area.

(Reporting By Ross Kerber; Editing by Paul Thomasch and Cynthia Osterman)

Source: http://news.yahoo.com/visitors-help-boston-shops-bounce-back-marathon-attacks-212025839.html

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