Saturday, July 20, 2013

Mobile skate park stops off in Beaconsfield (From Bucks Free Press)

Mobile skate park stops off in Beaconsfield

SKATEBOARDERS in Beaconsfield can get their fix this summer as a mobile skate park rolls into town.

South Bucks District Council is running its ?Skate Weekz? project over the holidays, with the mobile ramps coming to the Beacon Sports Centre for a week from August 26.

This comes after progress on a permanent skate park at Holtspur Way Recreation Ground stalled last month?following a disagreement among Beaconsfield town councillors over the best location to build the mooted course.

Councillor Anita Cranmer, SBDC's portfolio holder for community said: ?This is a great way to avoid those boredom blues and at the same time keep children physically active during the long summer break.?

The movable skate park comes to Beaconsfield after a two-week stay at Burnham Grammar School, with ramps and jumps for skaters and BMX riders.

?Skate Weekz? includes skateboarding competitions, prizes, tuition plus music and time for skaters to enjoy the ramps in their own way.

It is open to children aged 8 to 16 years. Activities run from 10am to 3pm, priced at ?4 per day and no prior booking is needed.

Helmets are compulsory and will be provided to all users, with water freely available and a limited number of skateboards can be hired for ?2 per day.

Under eights with some experience of using ramps are welcome, but will need to be accompanied by an adult for the duration of their stay.

Beaconsfield Town Council has set up a working group to look at the possibility of a permanent park for the town.

A plan to build it in Holtspur was drafted up, but councillors insisted alternative sites must be investigated before any decision is reached.

For more information please call the Sports Development Officer on 01895 837348 or email culturalandyouth@southbucks.gov.uk

?

Source: http://www.bucksfreepress.co.uk/news/10560705.Mobile_skate_park_stops_off_in_Beaconsfield/

redbox Nemo Storm weather forecast Rivals weather channel Kaepernick Eddie Vanderdoes

Roller coaster death at Six Flags Over Texas Under Investigation

A spokesperson for the park confirmed that the woman died while riding the Texas Giant roller coaster, but would not conform how she died. Witnesses however, told local news media that the woman tumbled over the side of the car, and screamed as the coaster made a sudden maneuver.

?Our thoughts and prayers are with the family. The investigation into the death at Texas Giant is still ongoing. We are working closely with authorities to determine the cause of the accident. The ride will remain closed. In addition, we have canceled the concert that was scheduled for today.?

According to the Dallas Morning News, other passengers on the ride were hysterical as they waited to disembark

John Putman told USA Today that he was in line awaiting his turn on the ride when the car from which the woman fell returned to the ground. Putman said a man and woman got out.

?They were screaming, ?My mom! My mom! Let us out, we need to go get her!? ? Putman said.

?She goes up like this. Then when it drops to come down, that?s when it (the safety bar) released and she just tumbled,? Carmen Brown of Arlington told The Dallas Morning News. Brown said she was waiting in line to get on the ride when the accident happened. She witnessed the woman being strapped into the ride.

?They didn?t secure her right. One of the employees from the park ? one of the ladies ? she asked her to click her more than once, and they were like, ?As long you heard it click, you?re OK.? Everybody else is like, ?Click, click, click.?? Brown told the newspaper.

?Hers only clicked once. Hers was the only one that went down once, and she didn?t feel safe, but they let her still get on the ride,? Brown said.

The ride, The New Texas Giant, won The Golden Ticket Award for best new ride of 2011 by Amusement Today magazine. It reaches 4 stories high and can carry up to 24 riders. It opened in 1990 as an all-wooden coaster and underwent renovation in 2010 to install steel hybrid rails.

The park clarified that the investigation is ?internal? and no other park attractions will be closed because of the accident.

Friday?s accident marked the second guest fatality since the park opened in 1961. The park?s first fatality happened in 1999. A 28-year-old Arkansas woman drowned and 10 other passengers were injured when a raft-like boat on the Roaring Rapids ride overturned in 2 to 3 feet (60 to 90 centimetres) of water.

New Texas Giant REAL POV Six Flags Over Texas Roller Coaster

Source:

Witness: Six Flags coaster victim concerned about seat

http://www.usatoday.com/story/news/nation/2013/07/19/women-dies-six-flags/2570527/

Texas Giant to remain closed as Six Flags investigates woman?s fall

http://www.dallasnews.com/news/metro/20130719-woman-falls-to-her-death-from-six-flags-texas-giant-roller-coaster.ece

Woman killed riding Texas Giant roller coaster at Six Flags

http://www.thespec.com/news-story/3902686-woman-killed-riding-texas-giant-roller-coaster-at-six-flags/


Source: http://www.dbtechno.com/curiosity/2013/07/20/roller-coaster-death-at-six-flags-over-texas-under-investigation/

supreme court ellen page Lisa Robin Kelly Jodi Arias Jane Wicker Snowden Nik Wallenda

Friday, July 19, 2013

South Africa Sri Lanka seek one-day revival

  • Reuters - Friday 19th July, 2013

    Fri Jul 19, 2013 8:06am EDT (Repeat for additional subscribers) July 19 (Reuters) - (The following statement was released by the rating agency) Fitch Ratings has assigned Sri Lanka-based Hatton National Bank PLC's (HNB; AA-(lka)/Stable) issue of unsecured, redeemable debentures of up to LKR3bn a final National Long-Term rating of 'AA-(lka)'. The assignment of the final rating follows ...

  • Not only Dayasiri I too will represent govt ? Harsha

    Ada Derana - Friday 19th July, 2013

    While continuously increasing taxes imposed on the public, the government has completely removed the income taxes on casino owners for a period of 10 years, the United National Party (UNP) charged today. UNP parliamentarian Dr Harsha de Silva stated that the government had issued the gazette notification at 12 midnight yesterday, providing sweeping tax concessions for Australian billionaire and ...

  • European lawmakers press Sri Lanka to probe war crimes

    General Sources - Friday 19th July, 2013

    COLOMBO (AFP) - European parliamentarians Friday asked Sri Lanka to deliver on promises to investigate allegations of war crimes and ensure ethnic reconciliation more than four years after crushing Tamil separatists.A delegation of EU lawmakers requested Colombo ensure accountability in the face of what the UN calls "credible allegations" of up to 40,000 civilians killed in the final ...

  • Sri Lanka stocks close at 1-week high

    Reuters - Friday 19th July, 2013

    COLOMBO, July 19 (Reuters) - Sri Lankan shares closed at their one-week high on Friday as investors bought diversified shares including in market heavyweight John Keells Holdings . The main share index ended 0.93 percent, or 55.61 points, firmer at 6,041.06, its highest closing since July 11. Foreign investors sold net 184 million rupees ($1.40 million) in shares. But the bourse has seen a net ...

  • Puducherry Govt warns fishermen from venturing into Sri Lankan waters

    Ada Derana - Friday 19th July, 2013

    The Puducherry government has warned fishermen against crossing the International Maritime Boundary Line and venturing into Sri Lankan waters and said action would be taken against violating the order.A notification of the Fisheries Department said the fishermen would face a penalty of INR 5000 and suspension of all kinds of financial and other benefits extended by the government if the penalty ...

  • Australia to send all asylum seekers arriving by boat to PNG

    Ada Derana - Friday 19th July, 2013

    Australian Prime Minister Kevin Rudd (right) and Papua New Guinea prime minister Peter ...

  • Eid Al Fitr Short Holiday in Sri Lanka

    Dubai Chronicle - Friday 19th July, 2013

    Many Dubai residents are planning to visit their families and distant relatives during the 3-day holiday marking the Eid Al-Fitr in August. If you wonder how to spend the celebration at the end ...

  • Trade between Sri Lanka and Malaysia to reach US$1 billion by 2015

    Asia News Network - Friday 19th July, 2013

    The 19th Annual General Meeting (AGM) of the Sri Lanka-Malaysia Business Council (SLMBC) was held on July 4 at the Ceylon Chamber of Commerce, Colombo. The council, which focuses on the objectives of "promoting investment, trade and joint venture between Sri Lanka and Malaysia", is one of the most dynamic bilateral business councils that function under the aegis of the Ceylon Chamber ...

  • Chinese tourist arrivals to Sri Lanka increasing steadily

    Asia News Network - Friday 19th July, 2013

    Chinese tourist arrivals to Sri Lanka is on a steady rise, with Sri Lanka having received 16,582 tourists from China during the first six months of this year, compared to 9,622 visitors received during the same period last year. This is a 72.3 percent year-on-year growth, and the jump is encouraging, as the Sri Lankan government has been working hard to capture a slice of the growing number of ...

  • Cricket Pakistan to host South Africa and Sri Lanka in UAE this year

    KeralaNext - Friday 19th July, 2013

    Cricket News: Karachi: A senior official of the PCB on Tuesday said that due to shortage of time the PCB had decided not to waste time and confirmed the Pakistan's upcoming series against South Africa and Sri Lanka in the ...

  • Cricket South Africa-Sri Lanka five-match ODI series starting on Saturday

    KeralaNext - Friday 19th July, 2013

    Cricket News: COLOMBO: Both South Africa and Sri Lanka were knocked out in the semi-finals of the Champions Trophy in the United Kingdom despite being rated as two of the strongest contenders in the eight-nation ...

  • Vaas Gunawardena further remanded till Aug 1

    Ada Derana - Friday 19th July, 2013

    Seven suspects in the murder of Bambalapitiya-based businessman Mohamed Siyam, including the former DIG Western Province (North) Vass Gunawardena, have been further remanded until August 01.The suspects were produced at the Colombo ...

  • Police bust fake money printing racket 8 arrested

    Ada Derana - Friday 19th July, 2013

    Eight persons including 2 women and 3 children were arrested after police raided a residence in the Poddala area in Galle after uncovering information regarding a counterfeit money printing operation.The raid was carried out by a team of officers from the Poddala Polcie Station who also discovered 9 fake Rs 1000 notes, 8 fake Rs 500 noted, a computer and various other equipment used for printing ...

  • SLFP central committee to meet for final decision

    Ada Derana - Friday 19th July, 2013

    The central committee of the Sri Lanka Freedom Party (SLFP) is scheduled to meet today to take a final decision regarding the candidates it will nominate to contest for the elections in the North, Central and North Western provinces. The party has already conducted interviews for the nominations while it has been reported that the selection of candidates has also ...

  • SA Sri Lanka seek ODI revival

    General Sources - Friday 19th July, 2013

    Colombo - South Africa and Sri Lanka are hoping to recover from recent setbacks in one-day cricket when they contest a five-match series starting in Colombo on Saturday.Both teams were knocked out in the semi-finals of the Champions Trophy in the United Kingdom despite being rated as two of the strongest contenders in the eight-nation tournament.The Proteas lived up to their reputation as ...

  • Sri Lankan government bans film on country?s civil war

    wsws.org - Friday 19th July, 2013

    (Flying Fish), by film director Sanjeewa Pushpakumara, and shut down a French film festival in Colombo where it was being screened. Government authorities and the state media have also made a series of chauvinist denunciations of Pushpakumara and film's ...

  • Karunanidhi seeking political mileage on Katchatheevu issue

    Ada Derana - Friday 19th July, 2013

    Lashing out at her arch rival and DMK president M Karunanidhi for moving the Supreme Court seeking retrieval of Katchatheevu island from Sri Lanka, Tamil Nadu Chief Minister J Jayalalithaa today termed it as ...

  • Tourist arrivals to Sri Lanka cross half-million mark

    eTN - Thursday 18th July, 2013

    COLOMBO, Sri Lanka - Aided by a healthy 13 percent improvement in June, tourist arrivals to post-war Sri Lanka in the first half of this year have crossed the half-a-million mark, latest data showed on Thursday. According to latest data released by the Sri Lanka Tourism Development Authority (SLTDA), arrivals between January and June amounted to 512,281, up by 13.1 percent over the first half ...

  • Cannot risk a parallel army in North - Basil

    Ada Derana - Thursday 18th July, 2013

    Basil Rajapaksa, Minister for Economic Development has told The Hindu newspaper that Sri Lanka would never risk a provincial government forming its ...

  • Govt. hospital doctors in Central Province launch token strike

    Ada Derana - Thursday 18th July, 2013

    Doctors of all government hospitals in the Central Province commenced a token strike today at 8am, the GMOA said. Accordingly the strike would be in effect for 24 hours from 8am, GMOA spokesman Dr. Naveendra Soysa told Ada ...

  • The Elders slam Sri Lanka for lacking reconciliation

    Sify - Thursday 18th July, 2013

    'The Elders', a council of retired global leaders led by Desmond Tutu has slammed Sri Lanka, based on its report, for lacking post-war reconciliation. They also expressed their disappointment over its slow pace of improvement in allowing "proper media reporting". "The ongoing persecution and disappearances of human rights activists, journalists and government opponents ...

  • Sri Lanka - Doubts as Sri Lanka says Commonwealth meeting open to media

    IFEX - Thursday 18th July, 2013

    The following is a CPJ Blog post by Sumit Galhotra, CPJ Asia Program Research Associate.As Sri Lanka prepares to host the biennial Commonwealth Heads of Government Meeting (CHOGM) in Colombo in November 2013, some journalists have wondered whether they will be able to access the summit given the island nation's abysmal press freedom record.On Saturday 13 July 2013, a subcommittee of the ...

  • Source: http://www.srilankannews.net/index.php/sid/215928260/scat/119937e494dd663e

    Isaac Hurricane earthquake san diego Hurricane Isaac Sam Claflin Tony Farmer West Nile virus symptoms snooki

    Strong 2Q Earnings for Dover

    Dover Corporation (DOV) reported second-quarter 2013 adjusted earnings from continuing operations of $1.36 per share, beating the Zacks Consensus Estimate of $1.29 and also exceeding the prior-year quarter?s earnings of $1.10 per share.

    On a reported basis, earnings from continuing operations were $1.70 per share, up 55% from $1.10 per share earned in the prior-year quarter. Earnings in the reported quarter include tax benefit of 36 cents per share and a charge of 2 cents per share related to the Knowles spin off. However, there were no adjustments in the prior-year quarter.

    Revenues and Margins
    ?
    Total revenue was $2.2 billion in reported quarter, up 9% year over year. The result was in line with the Zacks Consensus Estimate. The year-over-year rise includes an organic growth of 5%, a 4% contribution from acquisitions as well as a minor impact from foreign exchange.

    Dover witnessed solid growth from its businesses serving the consumer electronics and refrigeration markets along with contribution from energy and fluids businesses. Furthermore, Dover?s strategic decision to spin off certain parts of its communication technologies businesses also contributed to the growth. Additionally, revenues were driven by completion of four synergistic acquisitions.

    Cost of sales increased 8.8% to $1.37 billion in the quarter from $1.26 billion in the year-ago quarter. Gross profit went up 10% year over year to $856 million. Consequently, gross margin expanded 30 basis points (bps) to 38.4% in the quarter.

    Selling, general and administrative expenses increased 8.5% year over year to $505 million. Operating profit in the reported quarter increased 12.6% to $350 million. Operating margin also expanded 45 bps to 15.7% in the quarter.

    Segmental Performance

    Revenues in the Communication Technologies segment rose 11% year over year to $401 million in the reported quarter. The segment?s income also increased 3% year over year to $51.7 million.

    Energy revenues went up 6% to $573 million in the quarter. The segment?s operating income, however, decreased to $132.9 million from $133.9 million in the prior year quarter.

    Revenues in the Engineered Systems segment increased 13% to $1003.8 million in the quarter. The segment?s income also improved 23% to $165 million.

    Printing & Identification segment revenues were $250.6 million in the quarter compared with $251.8 million in the prior-year quarter. The segment reported an operating income of $35.9 million, increasing 24% from $28.9 million a year ago.

    Bookings and Backlog

    The company ended the second quarter with bookings worth $2.204 billion versus $2.038 billion at the end of the second quarter of 2012. Backlog increased year over year to $1.62 billion at end of the reported quarter compared with $1.61 million in the year ago quarter.

    Cash Flows

    The company generated cash flow from operating activities of $304.7 million in the reported quarter, up from $243.3 million in the prior-year quarter. Free cash flow was $251.4 million compared with $170.6 million in the prior-year quarter.

    Outlook for 2013

    Dover reiterated full year revenue growth in the range of 7%-9% in 2013. This assumes an organic revenue improvement of 3%-5% and a 4% contribution from acquisitions. However, the company raised its previous earnings guidance of $5.05-$5.35 per share. Dover now expects its new range for earnings to be $5.56-$5.71 per share for 2013.

    Our View

    Dover will continue to benefit from its active acquisition pipeline, bookings and orders growth. However, volatile semiconductor market and weak industrial market might weigh on the Printing and Identification segment and lower North American rig count will constrain growth in the Energy segment.

    Dover currently retains a short-term Zacks Rank #3 (Hold).

    Dover retains a short-term Zacks #3 Rank (Hold). Chart Industries Inc. (GTLS) and Gardner Denver Inc. (GDI) also belong to the diversified machinery industry; carrying a Zacks Rank #2 (Buy). One of Dover?s peers, Applied Industrial Technologies, Inc. (AIT) is slated to announce its fourth quarter and full year fiscal 2013 results on Aug 14.

    Read the Full Research Report on DOV

    Read the Full Research Report on GDI

    Read the Full Research Report on GTLS

    Zacks Investment Research

    More From Zacks.com

    Source: http://news.yahoo.com/strong-2q-earnings-dover-142944562.html

    Tim Curry amanda bynes bridge collapse Fast And Furious 6 Tony Kanaan Hangover 3 earthquake

    Google misses on earnings, stock drops

    Preeti Upadhyaya, Silicon Valley Business Journal

    Google Inc. posted net income of $3.3 billion for the second quarter, up 17 percent from a year ago thanks to growth in the company's advertising business. But the Mountain View company didn't perform as well as analysts had anticipated, and the stock dropped 5 percent in after-hours trading.

    Here's how the numbers break down:

    EPS

    Google pulled in earnings per share of $9.54, compared to $8.42 a year earlier.

    Revenue

    Revenue came in at $14.1 billion, compared to $11.8 billion a year prior.

    Missed estimate

    Analysts polled by Yahoo Finance and Thompson Reuters were expecting earnings of $10.78 a share on revenue of $14.4 billion.

    Tasty bits

    Total ad revenue jumped 15 percent to $13.1 billion. Read more about Google's Q2 results here and here.

    Source: http://feeds.bizjournals.com/~r/bizj_phoenix/~3/J8s4mvedPdg/google-misses-on-earnings-stock-drops.html

    drew brees usps Ola Ray Ginobili miley cyrus miley cyrus game 7

    Thursday, July 18, 2013

    Graphene 'onion rings' have delicious potential

    Graphene 'onion rings' have delicious potential [ Back to EurekAlert! ] Public release date: 18-Jul-2013
    [ | E-mail | Share Share ]

    Contact: David Ruth
    david@rice.edu
    713-348-6327
    Rice University

    Rice University lab grows 'bottom-up' nanoribbons for the first time

    Concentric hexagons of graphene grown in a furnace at Rice University represent the first time anyone has synthesized graphene nanoribbons on metal from the bottom up -- atom by atom.

    As seen under a microscope, the layers brought onions to mind, said Rice chemist James Tour, until a colleague suggested flat graphene could never be like an onion.

    "So I said, 'OK, these are onion rings,'" Tour quipped.

    The name stuck, and the remarkable rings that chemists marveled were even possible are described in a new paper in the Journal of the American Chemical Society.

    The challenge was to figure out how such a thing could grow, Tour said. Usually, graphene grown in a hot furnace by chemical vapor deposition starts on a seed -- a speck of dust or a bump on a copper or other metallic surface. One carbon atom latches onto the seed in a process called nucleation and others follow to form the familiar chicken-wire grid.

    Experiments in Tour's lab to see how graphene grows under high pressure and in a hydrogen-rich environment produced the first rings. Under those conditions, Tour, Rice theoretical physicist Boris Yakobson and their teams found that the entire edge of a fast-growing sheet of graphene becomes a nucleation site when hydrogenated. The edge lets carbon atoms get under the graphene skin, where they start a new sheet.

    But because the top graphene grows so fast, it eventually halts the flow of carbon atoms to the new sheet underneath. The bottom stops growing, leaving a graphene ring. Then the process repeats.

    "The mechanism relies on that top layer to stop carbon from reaching the bottom so easily," Tour said. "What we get are a multiple of single crystals growing one on top of the other."

    The Tour lab pioneered the bulk manufacture of single-atom-thick graphene nanoribbons in 2009 with the discovery that carbon nanotubes could be chemically "unzipped" into long, thin sheets. Nanoribbons are being studied for use in batteries and advanced electronics and as heat sinks.

    "Usually you make a ribbon by taking a large thing and cutting it down," Tour said. "But if you can grow a ribbon from the bottom up, you could have control of the edges." The atomic configuration at the edge helps determine graphene's electrical properties. The edges of hexagonal graphene onion rings are zigzags, which make the rings metallic.

    "The big news here," he said, "is that we can change relative pressures of the growth environment of hydrogen versus carbon and get entirely new structures. This is dramatically different from regular graphene."

    Graduate student Zheng Yan, a member of Tour's lab and lead author of the paper, discovered the new route to nanoribbons while experimenting with graphene growth under hydrogen pressurized to varying degrees. The sweet spot for rings was at 500 Torr, he said.

    Further testing found the microscopic rings formed underneath and not on top of the sheet, and Yakobson's lab confirmed the growth mechanism through first-principle calculations. Yan also determined the top sheet of graphene could be stripped away with argon plasma, leaving stand-alone rings.

    The width of the rings, which ranged from 10 to 450 nanometers, also affects their electronic properties, so finding a way to control it will be one focus of continued research, Tour said. "If we can consistently make 10-nanometer ribbons, we can begin to gate them and turn them into low-voltage transistors," he said. They may also be suitable for lithium storage for advanced lithium ion batteries, he said.

    ###

    Co-authors of the paper are Rice graduate students Yuanyue Liu, Zhiwei Peng, Changsheng Xiang, Abdul-Rahman Raji and Errol Samuel; postdoctoral researchers Jian Lin, Gunuk Wang and Haiqing Zhou; Rice alumna Elvira Pembroke; and Professor Ting Yu of Nanyang Technological University. Tour is the T.T. and W.F. Chao Chair in Chemistry as well as a professor of mechanical engineering and materials science and of computer science at Rice. Yakobson is the Karl F. Hasselmann Professor of Mechanical Engineering and Materials Science and professor of chemistry.

    The Singapore National Research Foundation, the Office of Naval Research, the Lockheed Martin LANCER IV program and the Air Force Office of Scientific Research supported the work. Calculations were performed on the National Science Foundation-supported DaVinCI supercomputer at Rice, the National Institute for Computational Sciences' Kraken and the National Energy Research Scientific Computing Center's Hopper.

    Read the abstract at http://pubs.acs.org/doi/abs/10.1021/ja403915m

    Follow Rice News and Media Relations via Twitter @RiceUNews

    Related Materials:

    Tour Group at Rice: http://www.jmtour.com

    Yakobson Group at Rice: http://biygroup.blogs.rice.edu


    [ Back to EurekAlert! ] [ | E-mail | Share Share ]

    ?


    AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert! system.


    Graphene 'onion rings' have delicious potential [ Back to EurekAlert! ] Public release date: 18-Jul-2013
    [ | E-mail | Share Share ]

    Contact: David Ruth
    david@rice.edu
    713-348-6327
    Rice University

    Rice University lab grows 'bottom-up' nanoribbons for the first time

    Concentric hexagons of graphene grown in a furnace at Rice University represent the first time anyone has synthesized graphene nanoribbons on metal from the bottom up -- atom by atom.

    As seen under a microscope, the layers brought onions to mind, said Rice chemist James Tour, until a colleague suggested flat graphene could never be like an onion.

    "So I said, 'OK, these are onion rings,'" Tour quipped.

    The name stuck, and the remarkable rings that chemists marveled were even possible are described in a new paper in the Journal of the American Chemical Society.

    The challenge was to figure out how such a thing could grow, Tour said. Usually, graphene grown in a hot furnace by chemical vapor deposition starts on a seed -- a speck of dust or a bump on a copper or other metallic surface. One carbon atom latches onto the seed in a process called nucleation and others follow to form the familiar chicken-wire grid.

    Experiments in Tour's lab to see how graphene grows under high pressure and in a hydrogen-rich environment produced the first rings. Under those conditions, Tour, Rice theoretical physicist Boris Yakobson and their teams found that the entire edge of a fast-growing sheet of graphene becomes a nucleation site when hydrogenated. The edge lets carbon atoms get under the graphene skin, where they start a new sheet.

    But because the top graphene grows so fast, it eventually halts the flow of carbon atoms to the new sheet underneath. The bottom stops growing, leaving a graphene ring. Then the process repeats.

    "The mechanism relies on that top layer to stop carbon from reaching the bottom so easily," Tour said. "What we get are a multiple of single crystals growing one on top of the other."

    The Tour lab pioneered the bulk manufacture of single-atom-thick graphene nanoribbons in 2009 with the discovery that carbon nanotubes could be chemically "unzipped" into long, thin sheets. Nanoribbons are being studied for use in batteries and advanced electronics and as heat sinks.

    "Usually you make a ribbon by taking a large thing and cutting it down," Tour said. "But if you can grow a ribbon from the bottom up, you could have control of the edges." The atomic configuration at the edge helps determine graphene's electrical properties. The edges of hexagonal graphene onion rings are zigzags, which make the rings metallic.

    "The big news here," he said, "is that we can change relative pressures of the growth environment of hydrogen versus carbon and get entirely new structures. This is dramatically different from regular graphene."

    Graduate student Zheng Yan, a member of Tour's lab and lead author of the paper, discovered the new route to nanoribbons while experimenting with graphene growth under hydrogen pressurized to varying degrees. The sweet spot for rings was at 500 Torr, he said.

    Further testing found the microscopic rings formed underneath and not on top of the sheet, and Yakobson's lab confirmed the growth mechanism through first-principle calculations. Yan also determined the top sheet of graphene could be stripped away with argon plasma, leaving stand-alone rings.

    The width of the rings, which ranged from 10 to 450 nanometers, also affects their electronic properties, so finding a way to control it will be one focus of continued research, Tour said. "If we can consistently make 10-nanometer ribbons, we can begin to gate them and turn them into low-voltage transistors," he said. They may also be suitable for lithium storage for advanced lithium ion batteries, he said.

    ###

    Co-authors of the paper are Rice graduate students Yuanyue Liu, Zhiwei Peng, Changsheng Xiang, Abdul-Rahman Raji and Errol Samuel; postdoctoral researchers Jian Lin, Gunuk Wang and Haiqing Zhou; Rice alumna Elvira Pembroke; and Professor Ting Yu of Nanyang Technological University. Tour is the T.T. and W.F. Chao Chair in Chemistry as well as a professor of mechanical engineering and materials science and of computer science at Rice. Yakobson is the Karl F. Hasselmann Professor of Mechanical Engineering and Materials Science and professor of chemistry.

    The Singapore National Research Foundation, the Office of Naval Research, the Lockheed Martin LANCER IV program and the Air Force Office of Scientific Research supported the work. Calculations were performed on the National Science Foundation-supported DaVinCI supercomputer at Rice, the National Institute for Computational Sciences' Kraken and the National Energy Research Scientific Computing Center's Hopper.

    Read the abstract at http://pubs.acs.org/doi/abs/10.1021/ja403915m

    Follow Rice News and Media Relations via Twitter @RiceUNews

    Related Materials:

    Tour Group at Rice: http://www.jmtour.com

    Yakobson Group at Rice: http://biygroup.blogs.rice.edu


    [ Back to EurekAlert! ] [ | E-mail | Share Share ]

    ?


    AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert! system.


    Source: http://www.eurekalert.org/pub_releases/2013-07/ru-gr071813.php

    bruno mars Hunter Hayes Born Sinner lil wayne Lolo Jones Steve Gleason blake shelton