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Welcome to the Nanoworld! A live demonstration of the new Scanning Electron Microscope in Aberdeen

Dr Alex Brasier and John Still

The limits of understanding commonly depend on what we can see with our eyes. In our daily lives, small objects measure millimetres, and large objects metres or kilometres.
But what we can see with our naked eyes is insufficient to understand many important aspects of the Earth and life: without basic optical microscopes we would never have seen the cells that we are all made of, or have any idea of the complexity of the eyes of a common housefly. One of the first to describe this Microworld was Robert Hooke, with his book “Micrographia” published in 1665. Optical microscopes are much improved since the days of Robert Hooke, and we can get some remarkable images with modern computer-aided optical microscopes with automated stages. But light can only be used to see objects on scales of millimetres to microns (millionths of a meter). There are many processes, such as the initial stages of crystal growth, that take place on scales of nanometers (billions of a meter) to microns. If we want to observe and understand these then we need to use a modern electron microscope equipped with a ‘Field Emission Gun’. Using electrons has some additional advantages. By using different detectors, we can get fabulous images of the topography of three dimensional specimens, or analyse their elemental compositions, or measure crystal structures and grain orientations. This talk will begin with an introduction to microscopy, with lots of nice pictures, though will mostly comprise a live demonstration of the new ACEMAC CarlZeiss GeminiSEM 300 VP (Schottky) FEG equipped with SE, BSE, CL, EDS and EBSD detectors. Acronyms will be explained as each feature is demonstrated! This new SEM can resolve objects measuring less than a nanometre in size, telling us both what samples look like and what they are made of. We will load an interesting selection of geological and non-geological specimens into the electron microscope, and while John Still operates the equipment down in the ACEMAC lab in the basement of the Meston Building, the live images will be shown on the screen in the lecture theatre.

Lecture and Christmas Party - Thursday December 7th, Meston Lecture Theatre 1 at 6:30pm.

We will adjourn to Room G05A after the lecture for drinks, nibbles and a Christmas raffle.