Microscopy as a Means for Nano-Characterization .


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Microscopy as a Means for Nano-Characterization. By Thomas Williams Phys 3500. What is Microscopy?. Microscopy is any technique for producing visible images of structures or details too small to otherwise be seen by the human eye. What is Nano Characterization?. What does it look like?
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Microscopy as a Means for Nano-Characterization By Thomas Williams Phys 3500

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What is Microscopy? Microscopy is any strategy for creating noticeable pictures of structures or points of interest too little to generally be seen by the human eye.

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What is Nano Characterization? What does it resemble? Measurements, structure, What is it made of? Atoms, natural extents What are it\'s properties? Physical, concoction, electromagnetic

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Why Microscopy? Keeping in mind the end goal to successfully consider something or assemble something it is critical to see precisely what it is we\'re doing. As the things we are occupied with get littler and littler we require all the more better, which means all the more capable microscopy. In the end this will require propels in the material science.

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The Origens of Microscopy In the primary century AD Romans created glass and started exploring different avenues regarding different shapes, discovering the merging focal point. In approx. 1590 Dutch eyeglass creators Hans and Zacharias Jensonn makes a compound magnifying instrument. Mid seventeenth century Anton Van Leeuwenhoek utilizes an enhanced single focal point magnifying lens to see and portray microorganisms, protozoan, and so on http://www.cas.muohio.edu/~mbi-ws/magnifying lens/history.html

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Age of the Optical Microscope In the late seventeenth century Robert Hooke included a third focal point, extraordinarily enhancing contrast issues and solace. Throughout the following two hundred years optical microscopy reforms science, particularly science. Amid this time upgrades are persistently made, including rectifications for chromatic round abnormalities. In the late nineteenth century, Ernst Abbe demonstrated that the change of the amplification of optical magnifying instruments was on a very basic level constrained by the wavelength of light. http://www.microscope-microscope.org/pictures/BWScope.jpg

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History of Electron Microscopy 1931-Ernst Ruska co-concocts the electron magnifying lens. 1938-10nm determination came to. 1940-2.4 nm determination. 1945-1.0nm determination accomplished. 1981-Gerd Binning and Heinrich Rohrer develop the examining burrowing electron magnifying instrument (STM). 1986-The Atomic Force Microscope was created in coordinated effort amongst IBM and Stanford University.

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Transmission Electron Microscope (TEM) Same rule as optical magnifying lens yet with electrons. Condenser opening stops high point electrons, initial phase in enhancing contrast. The target opening and chose region gap are discretionary yet can improve differentiate by blocking high point diffracted electrons Advantages: we can take a gander at non leading specimens, i.e. polymers, pottery, and natural examples. http://www.unl.edu/CMRAcfem/temoptic.htm

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TEM Images http://www.abdn.ac.uk/emunit/emunit/temcells/index.htm

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Scanning Electron Microscope (SEM) The SEM capacities much like an optical magnifying instrument however utilizes electrons rather than obvious light waves. The SEM utilizes an arrangement a progression of EM loops as focal points to center and control the electron bar. Tests must be got dried out and made conductive. Pictures are back and white. http://www.mos.org/sln/SEM/works/slideshow/semmov.html

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SEM Images http://www.mos.org/sln/SEM/works.html

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Scanning Tunneling Electron Microscope (STM) Basic rule is burrowing. Burrowing current streams amongst tip and test when isolated by under 100nm. The burrowing current gives us nuclear data about the surface as the tip checks. http://www.iap.tuwien.ac.at/www/surface/STM_Gallery/index.htmlx

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What is burrowing? The likelihood that the electron will exist outside the hindrance in the vacuum is non zero. On the off chance that these break out waves cover and a little inclination voltage is connected between the tip and the specimen, a burrowing current streams. The extent of this burrowing current does not give the atomic position specifically, but rather is straightforwardly relative to the electron thickness of the example at a point. http://www.chembio.uoguelph.ca/educmat/chm729/STMpage/stmdet.htm

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What does piezo-electric mean? In 1880 Pierre Curie found that by applying a weight to specific precious stones he could incite a potential over the gem. The STM turns around this procedure. Accordingly, by applying a voltage over a piezoelectric gem, it will prolong or pack. A regular piezoelectric material utilized as a part of a STM is Lead Zirconium Titanate.

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http://www.iap.tuwien.ac.at/www/surface/STM_Gallery/index.htmlx

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STM Images http://www.almaden.ibm.com/vis/stm/gallery.html

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Atomic Force Microscopy (AFM) AFM is performed by examining a sharp tip on the end of an adaptable cantilever over the example while keeping up a little drive. Run of the mill tip radii are on the request of 1nm to 10nm. AFM has two modes, tapping mode and contact mode. In checking mode, steady cantilever avoidance is kept up. In tapping mode, the cantilever is wavered at its reverberation recurrence. http://www.nanoscience.com/instruction/AFM.html http://www.azom.com/details.asp?ArticleID=3278

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AFM Images http://www.azom.com/details.asp?ArticleID=3278 http://www.nanoscience.com/index.html

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AFM Video http://www.nanoscience.com/training/gallery.html

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Future/Conclusions regardless we have far to go before we\'ve depleted the points of confinement of electron wavelength determination restrict. The wave length of a high vitality electron is on the request of .001nm or 1.0pm, our present best determination with a STM is just around .1nm. Restricting elements incorporate, aberations, differentiate,

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References Wikipedia - http://en.wikipedia.org/wiki/Main_Page History of the Microscope - http://www.cas.muohio.edu/~mbi-ws/magnifying lens/history.html Molecular Expressions - http://microscopy.fsu.edu/preliminary/exhibition hall/hornyolddissecting1920.html Dictionary.com - http://dictionary.reference.com/Micro-transport - http://www.microscope-microscope.org/magnifying lens home.html BBC H2G2 - http://www.bbc.co.uk/dna/h2g2/About.com - http://about.com/MOS - http://www.mos.org/sln/SEM/works/slideshow/semmov.html UNL - http://www.unl.edu/CMRAcfem/temoptic.htm IBM - http://www.ibm.com/us/AZOM.com - http://www.azom.com/default.asp Nanonscience Instruments - http://www.nanoscience.com/index.html

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Special Thanks Dr. Tapas Kar & the Fall 06 Nano-Chemistry Crew. Google, and their astonishing database of assets. Utah State, for seeing the developing need to offer classes in nanotechnology.

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