BEGIN:VCALENDAR VERSION:2.0 PRODID:-//Talks.cam//talks.cam.ac.uk// X-WR-CALNAME:Talks.cam BEGIN:VEVENT SUMMARY:"\;In situ liquid phase electron microscopy\, 3D imaging and H e ion microscopy"\; - Richard Langford\, Head of Cavendish Electron Mi croscopy Suite\, University of Cambridge\, UK. DTSTART:20191122T113000Z DTEND:20191122T123000Z UID:TALK135022@talks.cam.ac.uk CONTACT:Andrzej Szewczak-Harris DESCRIPTION:The Cavendish electron microscope suite houses a range of elec tron microscopes and auxiliary equipment. It is an SRF providing services and support across the University. The aim of this overview talk is to hig hlight and discuss some of the techniques the Suite can provide support fo r\, such as in situ nanoindentaion. Richard Langford\, the Facility Manage r will highlight the capabilities of the Suite using examples of his own r esearch to stimulate ideas and possible use into other projects. \n\nRicha rd’s current research focuses on the study of dentinal tubule occlusion using bioactive glasses. Bioactive glasses were originally developed for b one regeneration in war trauma injuries. The glass is a very open network structure which on contract with body fluids undergoes dissolution and dri ves the formation of hydroxyapatite like material. Part of Richard talk wi ll focus on the techniques he has been using and developing to quantify th e dentinal tubule occlusion when different toothpaste formulations are use d. The techniques presented will include focused ion beam slice and view\, X-ray tomography and in situ serial block microtoming. The relative advan tages and disadvantages of the techniques in terms of volumes that can be analysed\, time and spatial resolution will be discussed. Richard will als o discuss the methodology he has been involved in developing for cryo-TEM site specific specimen preparation and the cryo FIB/SEM possibilities with in the Suite which complement the cryo-TEM capabilities in the Biochemistr y Department. \n\nThe main part of Richard’s talk will focus on in situ liquid phase electron microscopy (LPEM) and the newly installed He ion ele ctron microscope. In situ LPEM enables a material system or process to be studied in real time in its native hydrated state at nm and atomic resolu tion while undertaking electrochemistry measurement using nanoelectrodes. It has been used to study battery processes\, cellular activities and corr osion. Richard will highlight this technique using his students’ studies on the dissolution of bioactive glasses. In this work we have been able t o visualise the dissolution of the bioglass and the repolymerised silica a cting as a centre for calcium phosphate nucleation. The Helium ion microsc ope is very similar to a SEM except it scans a beam of He ions. These can be used for imaging and nanomachining for example machining sub 3 nm pores . Differences in the He beam solid angles (relative to an electron beam) a nd sample interactions results in this imaging technique having a relative ly large depth of field and sub nm imaging. This tool is also equipped wit h a cryo stage and it is hoped that it can also be used for preparing site specific cryo-TEM samples with less damage to the side walls than would r esult when using a Ga beam. \n LOCATION:Department of Biochemistry\, Sanger Building\, Thomas Lecture The atre END:VEVENT END:VCALENDAR