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  • richardmitnick 1:07 pm on November 12, 2013 Permalink | Reply
    Tags: , , , , Nanotubes   

    From Berkeley Lab: “Taking a New Look at Carbon Nanotubes” 


    Berkeley Lab

    Berkeley Researchers Develop Technique For Imaging Individual Carbon Nanotubes

    November 12, 2013
    Lynn yarris (510) 486-5375 lcyarris@lbl.gov

    Despite their almost incomprehensibly small size – a diameter about one ten-thousandth the thickness of a human hair – single-walled carbon nanotubes come in a plethora of different “species,” each with its own structure and unique combination of electronic and optical properties. Characterizing the structure and properties of an individual carbon nanotube has involved a lot of guesswork – until now.

    Researchers with the U.S. Department of Energy (DOE)’s Lawrence Berkeley National Laboratory (Berkeley Lab) and the University of California (UC) Berkeley have developed a technique that can be used to identify the structure of an individual carbon nanotube and characterize its electronic and optical properties in a functional device.

    “Using a novel high-contrast polarization-based optical microscopy set-up, we’ve demonstrated video-rate imaging and in-situ spectroscopy of individual carbon nanotubes on various substrates and in functional devices,” says Feng Wang, a condensed matter physicist with Berkeley Lab’s Materials Sciences Division. “For the first time, we can take images and spectra of individual nanotubes in a general environment, including on substrates or in functional devices, which should be a great tool for advancing nanotube technology.”

    images
    In this display showing optical imaging and spectroscopy of an individual nanotube on substrates and in devices, (a–c) are schematics of a nanotube on a fused-silica substrate, in a field-effect transistor device with two gold electrodes, and under an alumina dielectric layer; (d–f) are SEM images and (g-i) are direct optical images of these individual nanotubes.

    See the full article here.

    A U.S. Department of Energy National Laboratory Operated by the University of California

    University of California Seal

    DOE Seal


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  • richardmitnick 5:17 pm on August 17, 2012 Permalink | Reply
    Tags: , , , , Computing For Clean Water (C4CW), , Nanotubes,   

    From Computing For Clean Water at WCG Status Update 

    World Community Grid (WCG) brings people together from across the globe to create the largest non-profit computing grid benefiting humanity. It does this by pooling surplus computer processing power. We believe that innovation combined with visionary scientific research and large-scale volunteerism can help make the planet smarter. Our success depends on like-minded individuals – like you.”

    “The Computing for Clean Water (C4CW) project has returned over 90 million results!”

    Mission
    The mission of Computing for Clean Water is to provide deeper insight on the molecular scale into the origins of the efficient flow of water through a novel class of filter materials. This insight will in turn guide future development of low-cost and more efficient water filters.

    Significance
    Lack of access to clean water is one of the major humanitarian challenges for many regions in the developing world. It is estimated that 1.2 billion people lack access to safe drinking water, and 2.6 billion have little or no sanitation. Millions of people die annually – estimates are 3,900 children a day – from the results of diseases transmitted through unsafe water, in particular diarrhea.

    Technologies for filtering dirty water exist, but are generally quite expensive. Desalination of sea water, a potentially abundant source of drinking water, is similarly limited by filtering costs. Therefore, new approaches to efficient water filtering are a subject of intense research. Carbon nanotubes, stacked in arrays so that water must pass through the length of the tubes, represent a new approach to filtering water.

    Approach
    Normally, the extremely small pore size of nanotubes, typically only a few water molecules in diameter, would require very large pressures and hence expensive equipment in order to filter useful amounts of water. However, in 2005 experiments showed that such arrays of nanotubes allow water to flow at much higher rates than expected. This surprising result has spurred many scientists to invest considerable effort in studying the underlying processes that facilitate water flow in nanotubes.

    This project uses large-scale molecular dynamics calculations – where the motions of individual water molecules through the nanotubes are simulated – in order to get a deeper understanding of the mechanism of water flow in the nanotubes. For example, there has been speculation about whether the water molecules in direct contact with the nanotube might behave more like ice. This in turn might reduce the friction felt by the rest of the water, hence increasing the rate of flow. Realistic computer simulations are one way to test such hypotheses.

    Ultimately, the scientists hope to use the insights they glean from the simulations in order to optimize the underlying process that is enabling water to flow much more rapidly through nanotubes and other nanoporous materials. This optimization process will allow water to flow even more easily, while retaining sources of contamination. The simulations may also reveal under what conditions such filters can best assist in a desalination process.”

    C4CF had its origin in the Center for Nano and Micro Mechanics at Tsinghua University, Beijing, China

    From CNMM

    “The Computing for Clean Water (C4CW) project is a joint project between CNMM and several international research institutions [The University of Sydney, Monash University, The National Centre of Nanoscience and Technology, Chinese Academy of Sciences, Institute of High Energy Physics, The Citizen Cyberscience Centre, with the support of IBM’s World Community Grid, and thousands of volunteers.

    The team at CNMM is investigating how water flows in nanotubes, using a computer-based simulation technique known as molecular dynamics. The ultimate goal of this research is deeper insight into how nanotubes and other porous nanomaterials can be used to build a new generation of cheap water filters, to alleviate the pressing demand for clean water in large parts of China and many other parts of the developing world.

    To do these simulations with the sort of accuracy we need takes a lot of computing power, far more than is accessible to us currently. Volunteers provide this computing power by allowing some simulations to run using the idle time of the processor chips in their laptops and PCs, for example while they are writing emails or surfing the web. Indeed, when doing these common tasks, the processor is idle often more than 90% of the time, and using some of that idle time turns out to be energetically very efficient, since it only adds a few percent extra power to what the computer would otherwise consume.

    The results from each simulation, when combined together statistically for millions of runs, help us create a pool of necessary data that can be analyzed to understand why recent experiments show that water flows much more easily in nanotubes than standard hydrodynamical considerations would normally lead us to believe. Understanding this process is a first step to optimizing it for practical purposes, in particular to make cheaper filters that do not require so much pressue to filter water through them.
    This is an exciting project, but it is also complicated and will run over some time. World Community Grid enables scientists and volunteers to co-operate in a very simple and powerful way. We are grateful for the continuing support of every one of our volunteers and will post our progress here to keep you updated.”

    WCG projects run on BOINC software from UC Berkeley.

    BOINC is a leader in the field(s) of Distributed Computing, Grid Computing and Citizen Cyberscience.BOINC is more properly the Berkeley Open Infrastructure for Network Computing.

    CAN ONE PERSON MAKE A DIFFERENCE? YOU BETCHA!!

    “Download and install secure, free software that captures your computer’s spare power when it is on, but idle. You will then be a World Community Grid volunteer. It’s that simple!” You can download the software at either WCG or BOINC.

    Please visit the project pages-

    Say No to Schistosoma
    sch

    GO Fight Against Malaria
    mal

    Drug Search for Leishmaniasis
    lish

    Computing for Clean Water
    c4cw

    The Clean Energy Project
    cep2

    Discovering Dengue Drugs – Together
    dengue

    Help Cure Muscular Dystrophy
    md

    Help Fight Childhood Cancer
    hccf

    Help Conquer Cancer
    hcc

    Human Proteome Folding
    hpf

    FightAIDS@Home
    faah

    Computing for Sustainable Water

    World Community Grid is a social initiative of IBM Corporation
    IBM Corporation
    ibm

    IBM – Smarter Planet
    sp


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    • richardmitnick 12:16 pm on September 5, 2012 Permalink | Reply

      Jefferson- Thanks for the vote of confidence. WCG projects are direct ed at immediate problems for life around the globe.

      Like

  • richardmitnick 12:54 pm on July 19, 2012 Permalink | Reply
    Tags: , , , , Nanotubes   

    From MIT News: “Dripping faucets inspire new way of creating structured particles” 

    July 18, 2012
    David L. Chandler

    Researchers at MIT and the University of Central Florida (UCF) have developed a versatile new fabrication technique for making large quantities of uniform spheres from a wide variety of materials — a technique that enables unprecedented control over the design of individual, microscopic particles. The particles, including complex, patterned spheres, could find uses in everything from biomedical research and drug delivery to electronics and materials processing.

    drip
    This illustration shows how a molten fiber, because of a phenomenon known as Rayleigh instability, naturally breaks up into spherical droplets. Researchers from MIT and UCF have figured out how to use this natural tendency as a way to make large quantities of perfectly uniform particles, which can have quite complex structures. Image: Yan Liang/Fink Lab

    See the full article here.

     
  • richardmitnick 9:44 pm on July 17, 2012 Permalink | Reply
    Tags: , , , Nanotubes   

    From Argonne Lab: “Synthetic nanotubes lay foundation for new technology: Artificial pores mimic key features of natural pores” 

    News from Argonne National Laboratory

    July 17, 2012
    No writer credit

    Scientists have overcome key design hurdles to expand the potential uses of nanopores and nanotubes. The creation of smart nanotubes with selective mass transport opens up a wider range of applications for water purification, chemical separation and fighting disease.

    synth
    A snapshot of a helical stack of macryocycles generated in the computer simulation. NO image credit

    Nanopores and their rolled up version, nanotubes, consist of atoms bonded to each other in a hexagonal pattern to create an array of nanometer-scale openings or channels. This structure creates a filter that can be sized to select which molecules and ions pass into drinking water or into a cell. The same filter technique can limit the release of chemical by-products from industrial processes.

    Successes in making synthetic nanotubes from various materials have been reported previously, but their use has been limited because they degrade in water, the pore size of water-resistant carbon nanotubes is difficult to control, and, more critically, the inability to assemble them into appropriate filters.

    An international team of researchers, with help of the Advanced Photon Source at Argonne National Laboratory, have succeeded in overcoming these hurdles by building self-assembling, size-specific nanopores. This new capability enables them to engineer nanotubes for specific functions and use pore size to selectively block specific molecules and ions.”

    See the full article here.

    Argonne is managed by UChicago Argonne, LLC for the U.S. Department of Energy’s Office of Science

     
  • richardmitnick 2:13 pm on July 11, 2012 Permalink | Reply
    Tags: , , , , , , , , Nanotubes   

    From MIT News: “Researchers explain how dye-based nanotubes can help harvest light’s energy” 

    July 6, 2012
    David L. Chandler

    Companies that make commercial solar cells are happy if they can achieve 20 percent efficiency when converting sunlight to electricity; an improvement of even 1 percent is seen as major progress. But nature, which has had billions of years to fine-tune photosynthesis, can do much better: Microorganisms called green sulfur bacteria, which live deep in the ocean where there’s hardly any light available, manage to harvest 98 percent of the energy in the light that reaches them.

    sulfer
    Green sulfur bacteria, whose exceptional light-harvesting capabilities inspired the artificial system analyzed by postdoc Dörthe Eisele and her co-workers, dominate this hot spring at Yellowstone National Park and give it its striking green color.

    Now, researchers led by an MIT postdoc have analyzed an artificial system that models the light-capturing method used by deep-sea bacteria. Further advances in understanding fundamental light-harvesting processes may yield entirely new approaches to capturing solar energy, the researchers say. Their results were reported July 1 in the journal Nature Chemistry.”

    See the full article here.

     
  • richardmitnick 1:38 pm on June 29, 2011 Permalink | Reply
    Tags: , , , Nanotubes   

    From Berkeley Labs: “Splitsville for Boron Nitride Nanotubes” 

    Lynn Yarris
    June 28, 2011

    Berkeley Lab Researchers Find New Way to Mass Produce High Quality Boron Nitride Nanoribbons

    “Scientists with the Lawrence Berkeley National Laboratory (Berkeley Lab) and the University of California (UC) Berkeley, working with scientists at Rice University, have developed a technique in which boron nitride nanotubes are stuffed with atoms of potassium until the tubes split open along a longitudinal seam. This creates defect-free boron nitride nanoribbons of uniform lengths and thickness. Boron nitride nanoribbons are projected to display a variety of intriguing magnetic and electronic properties that hold enormous potential for future devices.

    i1
    Splitting of a boron nitride nanotube to form a boron nitride nanoribbon shows atoms of boron in blue, nitrogen in yellow and potassium in pink. Pressure from potassium intercalation unzips the BNNT and forms layers of BNNRs.

    ‘There has been a significant amount of theoretical work indicating that, depending on the ribbon edges, boron nitride nanoribbons may exhibit ferromagnetism or anti-ferromagnetism, as well as spin-polarized transport which is either metallic or semi-conducting,’ says physicist Alex Zettl, one of the world’s foremost researchers into nanoscale systems and devices who holds joint appointments with Berkeley Lab’s Materials Sciences Division (MSD) and the Physics Department at UC Berkeley, where he is the director of the Center of Integrated Nanomechanical Systems (COINS)”

    i2
    Alex Zettl holds joint appointments with Berkeley Lab and UC Berkeley where he directs the Center of Integrated Nanomechanical Systems.

    See the full article here.

    A U.S. Department of Energy National Laboratory Operated by the University of California

    i1
    i2

     
  • richardmitnick 5:24 am on October 23, 2010 Permalink | Reply
    Tags: , Nanotubes   

    Lawrence Livermore National Laboratory and Carbon Nanotubes 

    So, for the first time in this space, I see an interaction between the publicly funded national research labs and private for profit industry. It does make sense. It is not that scientific research discoveries need to be commercialized, rather it is that in many cases, they do lead us to a better environment, or health, or just good old happy living.

    So, here is the story of LLNL and carbon nanotubes.

    Carbon nanotube research garners Energy Commission funding

    Anne M Stark writes, “Researchers in carbon nanotubes, originally developed at the Laboratory, have been awarded more than $100,000 by the California Energy Commission to apply the technology to curbing industrial pollution.

    Hayward-based Porifera, Inc., headed by former Lab scientist Olgica Bakajin, was awarded $115,397 for a project to research and develop carbon nanotube membranes to efficiently separate carbon dioxide from industrial emissions. The project budget is $1,442,469, with $1,153,975 coming from an American Recovery and Reinvestment Act (ARRA) grant. The company will provide $173,097 in funds for the project.

    olga
    Olgica Bakajin

    The goal of the project is to replace the chemical-based carbon dioxide separation technology with membrane-based technology. Carbon nanotube membranes are comprised of extremely small (about 10,000 times smaller than a human hair) and strong hollow tubes made of graphite carbon atoms. Gas flows through these tubes 100 times faster than the pores in other types of membranes.”

    You know, as I read that, I had to wonder about the letting of this contract to someone not exactly at fully arms length. I remembered the story about someone who started a business while working as a buyer at a large industrial company. He wrote himself a really nice order in moderate five figures and then left his employer to go run his business.

    More of the article: “Bakajin formerly worked at LLNL where she was recruited in 2000 as a Lawrence Fellow and then moved on to become chief scientist on the carbon nanotube project along with LLNL alumnus Aleksandr Noy, another former Lawrence Fellow. The license was awarded through LLNL’s Industrial Partnership Office.”

    It is certainly not up to me to question the relationship and transaction, but boy oh boy, do I wish it was.

    “The goal of the project is to replace the chemical-based carbon dioxide separation technology with membrane-based technology. Carbon nanotube membranes are comprised of extremely small (about 10,000 times smaller than a human hair) and strong hollow tubes made of graphite carbon atoms. Gas flows through these tubes 100 times faster than the pores in other types of membranes.

    If successful, carbon nanotube membranes could potentially deliver better efficiency, lower energy consumption, and provide cheaper carbon dioxide sequestration than the current process. The research team for the project includes scientists and engineers from Porifera, Lawrence Livermore and the University of California at Berkeley.”

    nano
    Artist’s rendering of methane molecules flowing through a carbon nanotube less than two nanometers in diameter. Image by Scott Dougherty

    You can read the complete article here.

    So, another story of saving the environment and saving money, at one of our great national laboratories.

     
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