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MicroscopyPioneers


Pioneers in in situ Electron Microscopy: Lawrence (Larry) Allard, Oak Ridge National Laboratory


Cameron Varano Te Pennsylvania State University, 201 Old Main, University Park, PA 16802 cvarano@psu.edu


Lawrence (Larry) Allard (born 1943)


While it is true that the story of


Dr. Lawrence (Larry) Allard begins with his birth on October 28, 1943, the first 18 years were unremarkable in regard to microscopy. Te story of how he came to be a pioneer in the field of in situ microscopy begins in the summer of 1961, aſter he graduated high school in Grand Rapids, Minnesota, and moved to Detroit. In Detroit, his aim was to live frugally and work long hours in a meat-packing facility to earn enough money for college, which he accomplished in 15 months. His scholastic aptitude also earned him a scholarship to Michigan State University, which would have covered nearly four semesters of tuition. However, his cousin was a graduate of the University of Michigan and intervened to redirect Allard to Michigan where he began in the fall of 1962. The money earned at the meat-packing plant should


Lawrence (Larry) Allard


have been enough to get him through most of his under- graduate training. However, it seems that the freshman year of college has a universal effect on young students, and after his first year at the University of Michigan, he was in need of employment. As a freshman in his sec- ond semester, he was wandering the halls of a university engineering building and passed a door labeled “Elec- tron Microscope.” The phrase piqued his interest, so he entered and found someone sitting in the dark looking into the glowing window of a “wonderful instrument.” After promising not to ask questions, he was allowed to watch. The experience bewitched him, although he did not have a clue about any of it. Shortly afterwards, he attended an information session run by Professor Wil- bur Bigelow. Each student was asked to write their inter- ests on a card. Allard wrote of one interest: “the electron microscope.” This ignited a relationship with Professor Bigelow in the fall of 1963, which continues in collabo- ration to this day. After proving his interests and wits,


52 doi:10.1017/S1551929520000267


Allard earned a paying position in the Bigelow lab as a research assistant where he was able to earn enough to cover his tuition and discover his passion. In 1965 Prof. Bigelow and Prof. Lawrence Brockway


were collaborating on a new project funded by the Oak Ridge Gaseous Diffusion Plant (ORGDP) to study gas reactions on single crystals of copper, and they wanted to do it using in situ electron microscopy. Brockway and Bigelow built a top-entry heating stage and gas-handling manifold for the JEOL JEM-6A 100 kv electron micro- scope. Allard was tasked with building the heaters and the daily operation of


the microscope. The platform,


while rudimentary compared to today’s instrumentation, had the capability to heat to ∼500°C, with reaction gas fed directly into the column. The experiments began by annealing single-crystal foils with hydrogen gas. Then hydrogen was exchanged with oxygen at pressures test- ing the limit of the microscope’s vacuum. The oxygen had the inconvenient side effect of burning out the tungsten filament every few days. Yet, it worked, and the formation of copper oxide grains was recorded using a 16 mm cine


Figure 2: Dr. Larry Allard at the JEOL JEM-6A TEM during the summer of 1965. The gas manifold included hard coupling to the column, gas purification capability, and reasonable pressure measurement with BA and Pirani gauges.


www.microscopy-today.com • 2020 March


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