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Full 3-D image of nanocrystals' interior created by shining X-rays through them
July 06, 2006A vital step towards the ultimate goal of being able to take 'photographs' of individual molecules in action has been achieved by an international team led by UCL (University College London) researchers at the London Centre for Nanotechnology.
They report in the journal Nature on a novel method of obtaining a full 3-D image of the interior of nanocrystals. Using a process known as coherent X-ray diffraction imaging, they were able to build a picture of the inside of nanocrystals by measuring and inverting diffraction patterns.
Ultimately, the technique will help in the development of X-ray free-electron lasers, which will allow single-molecule imaging. It will also allow researchers to more accurately assess the defects in any given material which gives them specific properties.
Professor Ian Robinson, of the UCL Department of Physics & Astronomy and the London Centre for Nanotechnology, who led the study, says: "This new imaging method shows that the interior structure of atomic displacements within single nanocrystals can be obtained by direct inversion of the diffraction pattern. We hope one day this will be applied to determine the structure of single protein molecules placed in the femtosecond beam of a free-electron laser.
"Coherent X-ray diffraction imaging emerged from the realisation that over-sampled diffraction patterns can be inverted to obtain real space images. It is an attractive alternative to electron microscopy because of the better penetration of the electromagnetic waves in materials of interest, which are often less damaging to the sample than electrons.\\\
University College London
Professor Ian Robinson, of the UCL Department of Physics & Astronomy and the London Centre for Nanotechnology, who led the study, says: "This new imaging method shows that the interior structure of atomic displacements within single nanocrystals can be obtained by direct inversion of the diffraction pattern. We hope one day this will be applied to determine the structure of single protein molecules placed in the femtosecond beam of a free-electron laser.
"Coherent X-ray diffraction imaging emerged from the realisation that over-sampled diffraction patterns can be inverted to obtain real space images. It is an attractive alternative to electron microscopy because of the better penetration of the electromagnetic waves in materials of interest, which are often less damaging to the sample than electrons.\\\
University College London
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A team of engineers from the University of Pennsylvania has transformed simple nanowires into reconfigurable materials and circuits, demonstrating a novel, self-assembling method for chemically creating nanoscale structures that are not possible to grow or obtain otherwise.
Gold Solution for Enhancing Nanocrystal Electrical Conductance
In a development that holds much promise for the future of solar cells made from nanocrystals, and the use of solar energy to produce clean and renewable liquid transportation fuels, researchers with the U.S. Department of Energy's Lawrence Berkeley National Laboratory (Berkeley Lab) have reported a technique by which the electrical conductivity of nanorod crystals of the semiconductor cadmium-selenide was increased 100,000 times.
Building better bone replacements with bacteria
Bacteria that manufacture hydroxyapatite (HA) could be used to make stronger, more durable bone implants. Professor Lynne Macaskie from the University of Birmingham this week (7-10 September) presented work to the Society for General Microbiology's meeting at Heriot-Watt University, Edinburgh.
Pitt researchers harness carbon nanomaterials for drug delivery systems, oxygen sensors
Two nanoscale devices recently reported by University of Pittsburgh researchers in two separate journals harness the potential of carbon nanomaterials to enhance technologies for drug or imaging agent delivery and energy storage systems, in one case, and, in the other, bolster the sensitivity of oxygen sensors essential in confined settings, from mines to spacecrafts.
Growth Spurts: Berkeley Lab Researchers Record First Real-Time Direct Observations of Nanocrystal Growth in Solution
The veil is being lifted from the once unseen world of molecular activity. Not so long ago only the final products were visible and scientists were forced to gauge the processes behind those products by ensemble averages of many molecules.
Jet-propelled Imaging for an Ultrafast Light Source
John Spence, a physicist at Arizona State University, is a longtime user of the Advanced Light Source at Lawrence Berkeley National Laboratory, where he has contributed to major advances in lensless imaging.
More Than Meets the Eye: New Blue Light Nanocrystals
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Nanocrystals Reveal Activity Within Cells
Researchers at the U.S. Department of Energy's (DOE) Lawrence Berkeley National Laboratory have created bright, stable and bio-friendly nanocrystals that act as individual investigators of activity within a cell.
Major Breakthrough in Early Detection and Prevention of AMD
A team of researchers led by Dr. Jayakrishna Ambati at the University of Kentucky has discovered a biological marker for neovascular age-related macular degeneration (AMD), the leading cause of blindness in older adults.
Discovery of non-blinking semiconductor nanocrystals advances their applications
Substantial advances for applications of nanocrystals in the fields requiring a continuous output of photons and high quantum efficiency may soon be realized due to discovery of non-blinking semiconductor nanocrystals.
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