Clarence Edward Larson (September 20, 1909 – February 15, 1999) was an American chemist, nuclear physicist and industrial leader. He was involved in the

Manhattan Project The Manhattan Project was a research and development undertaking during World War II that produced the first nuclear weapons. It was led by the United States with the support of the United Kingdom and Canada. From 1942 to 1946, the project w ...

, and was later director of

Oak Ridge National Laboratory Oak Ridge National Laboratory (ORNL) is a U.S. multiprogram science and technology national laboratory sponsored by the U.S. Department of Energy (DOE) and administered, managed, and operated by UT–Battelle as a federally funded research and ...

and commissioner of the

U.S. Atomic Energy Commission The United States Atomic Energy Commission (AEC) was an agency of the United States government established after World War II by U.S. Congress to foster and control the peacetime development of atomic science and technology. President ...

Early life and education

Larson was born in

Cloquet, Minnesota Cloquet ( ) is a city in Carlton County, Minnesota, United States, at the junction of Interstate 35 and Minnesota State Highway 33. Part of the city lies within the Fond du Lac Indian Reservation and serves as one of the reservation's three admi ...

, in 1909. As a teenager he was involved in church groups and the local

YMCA YMCA, sometimes regionally called the Y, is a worldwide youth organization based in Geneva, Switzerland, with more than 64 million beneficiaries in 120 countries. It was founded on 6 June 1844 by George Williams in London, originally ...

, and occasionally acted as a substitute minister at nearby parishes. In his primary education, Larson was selected for a class that combined both

seventh Seventh is the ordinal form of the number seven. Seventh may refer to: * Seventh Amendment to the United States Constitution * A fraction (mathematics), , equal to one of seven equal parts Film and television *"The Seventh", a second-season e ...

and eighth grades which meant he entered high school a year younger than his peers. In high school he created his own

telegraph Telegraphy is the long-distance transmission of messages where the sender uses symbolic codes, known to the recipient, rather than a physical exchange of an object bearing the message. Thus flag semaphore is a method of telegraphy, whereas p ...

network between his neighbors' houses by collecting discarded parts from the

Bell telephone company The Bell Telephone Company, a common law joint stock company, was organized in Boston, Massachusetts, on July 9, 1877, by Alexander Graham Bell's father-in-law Gardiner Greene Hubbard, who also helped organize a sister company – the New Englan ...

. He had not intended to attend university as very few high school graduates in his home town did so. Larson studied chemistry and chemical engineering at the

University of Minnesota The University of Minnesota, formally the University of Minnesota, Twin Cities, (UMN Twin Cities, the U of M, or Minnesota) is a public university, public Land-grant university, land-grant research university in the Minneapolis–Saint Paul, Tw ...

, graduating in 1932, and obtained a Ph.D. at the

University of California, Berkeley The University of California, Berkeley (UC Berkeley, Berkeley, Cal, or California) is a public land-grant research university in Berkeley, California. Established in 1868 as the University of California, it is the state's first land-grant u ...

, studying blood clotting. While there, Larson designed a

glass electrode A glass electrode is a type of ion-selective electrode made of a doped glass membrane that is sensitive to a specific ion. The most common application of ion-selective glass electrodes is for the measurement of pH. The pH electrode is an example ...

in order to measure the acidity of flowing solutions. His later work focused on isotopes produced by a

cyclotron A cyclotron is a type of particle accelerator invented by Ernest O. Lawrence in 1929–1930 at the University of California, Berkeley, and patented in 1932. Lawrence, Ernest O. ''Method and apparatus for the acceleration of ions'', filed: Janu ...

, invented by his future colleague

Ernest Lawrence Ernest Orlando Lawrence (August 8, 1901 – August 27, 1958) was an American nuclear physicist and winner of the Nobel Prize in Physics in 1939 for his invention of the cyclotron. He is known for his work on uranium-isotope separation f ...

. His study of the behavior of ions in electric fields gave him a good understanding of

electrochemistry Electrochemistry is the branch of physical chemistry concerned with the relationship between electrical potential difference, as a measurable and quantitative phenomenon, and identifiable chemical change, with the potential difference as an outco ...

, which he would later come to use in the Manhattan Project. From 1939 to 1942 Larson chaired the Chemistry Department at the College of the Pacific, where he continued his cyclotron research, which led to his recruitment into the Manhattan Project.

Y-12 National Security Complex

Larson was senior chemist from 1942 to 1945 on Ernest Lawrence's team that oversaw the construction and operation of the

Y-12 National Security Complex The Y-12 National Security Complex is a United States Department of Energy National Nuclear Security Administration facility located in Oak Ridge, Tennessee, near the Oak Ridge National Laboratory. It was built as part of the Manhattan Proje ...

. The plant used electromagnetic

isotope separation Isotope separation is the process of concentrating specific isotopes of a chemical element by removing other isotopes. The use of the nuclides produced is varied. The largest variety is used in research (e.g. in chemistry where atoms of "marker" n ...

to produce most of the

uranium-235 Uranium-235 (235U or U-235) is an isotope of uranium making up about 0.72% of natural uranium. Unlike the predominant isotope uranium-238, it is fissile, i.e., it can sustain a nuclear chain reaction. It is the only fissile isotope that exis ...

for

Little Boy "Little Boy" was the type of atomic bomb dropped on the Japanese city of Hiroshima on 6 August 1945 during World War II, making it the first nuclear weapon used in warfare. The bomb was dropped by the Boeing B-29 Superfortress ''Enola Gay'' p ...

, the nuclear bomb dropped on Hiroshima. Larson suggested and oversaw improvements to the plant that increased the yield of the process. Uranium atoms were buried in the walls of the stainless steel receivers by the

calutron A calutron is a mass spectrometer originally designed and used for separating the isotopes of uranium. It was developed by Ernest Lawrence during the Manhattan Project and was based on his earlier invention, the cyclotron. Its name was derived ...

s, then recovered chemically. Larson's solution was to copper-plate the receivers, which increased the yield as more atoms could be more easily recovered from copper than stainless steel. In 1948, Larson became the director of the Y-12 Complex.

Oak Ridge National Laboratory

In 1950, Larson was appointed director of Oak Ridge National Laboratory. He oversaw a US$20 million (US$255 million in 2013) expansion of the laboratory, the creation of three nuclear reactors at the site, and a partnership with the

U.S. Navy The United States Navy (USN) is the maritime service branch of the United States Armed Forces and one of the eight uniformed services of the United States. It is the largest and most powerful navy in the world, with the estimated tonnage o ...

to design

nuclear-powered ships Nuclear power is the use of nuclear reactions to produce electricity. Nuclear power can be obtained from nuclear fission, nuclear decay and nuclear fusion reactions. Presently, the vast majority of electricity from nuclear power is produced b ...

. He also began an experiment into nuclear-powered aircraft. He served as director until 1955.

Union Carbide

In 1955, Larson left

Oak Ridge, Tennessee Oak Ridge is a city in Anderson and Roane counties in the eastern part of the U.S. state of Tennessee, about west of downtown Knoxville. Oak Ridge's population was 31,402 at the 2020 census. It is part of the Knoxville Metropolitan Area. Oak ...

, to become vice president of the National Carbon Division of

Union Carbide Corporation Union Carbide Corporation is an American chemical corporation wholly owned subsidiary (since February 6, 2001) by Dow Chemical Company. Union Carbide produces chemicals and polymers that undergo one or more further conversions by customers befo ...

. He returned to Oak Ridge from 1961 to 1969, as president of Union Carbide Nuclear Division, when the company was tasked with management of Oak Ridge National Laboratory. He oversaw management of the laboratory, the Y-12 Plant and the K-25 Gaseous Diffusion Plant, and was also responsible for the

Paducah Gaseous Diffusion Plant The Paducah Gaseous Diffusion Plant (PGDP) is a facility located in McCracken County, Kentucky, near Paducah, Kentucky that produced enriched uranium from 1952 to 2013. It is owned by the U.S. Department of Energy (DOE). The PGDP was the only op ...

Atomic Energy Commission

Larson was appointed commissioner of the

thanks to his reputation as a "knowledgeable and judicious administrator". He served as commissioner from 1969 to 1974, a time of great uncertainty for the nuclear industry. He commissioned a series of public hearings on nuclear reactor safety, especially concerning emergency cooling. The AEC turned to Larson's former employer, Oak Ridge National Laboratory, to aid in the formation of reactor regulations.

Personal life

Larson was married twice, first to Jerry and later to Jane Warren. He had three sons. He died in 1999 of pneumonia at a hospital in

Bethesda, Maryland Bethesda () is an unincorporated, census-designated place in southern Montgomery County, Maryland. It is located just northwest of Washington, D.C. It takes its name from a local church, the Bethesda Meeting House (1820, rebuilt 1849), which in ...

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Accolades

Larson was elected to the

National Academy of Engineering The National Academy of Engineering (NAE) is an American nonprofit, non-governmental organization. The National Academy of Engineering is part of the National Academies of Sciences, Engineering, and Medicine, along with the National Academy ...

in 1973 for "the development of processes for recovery and purification of uranium and leadership in nuclear plant design."

Publications

*''The Relation of the Physical-Chemical States of Blood Calcium'', 1937 *''Uranium and Hydrogen Functions of Uranium Glass Electrodes'' - with H. W. Alter, Thomas William Newton, published by U.S. Atomic Energy Commission, Technical Information Branch, 1949 *''The Scientist and Creativity'' - published by U.S. Atomic Energy Commission, 1969 *''Technology and Economy of Light Water Reactors'', 1973

References

External links

1965 Audio Interview with Clarence Larson by Stephane Groueff
Voices of the Manhattan Project
Video interview with Larson
{{DEFAULTSORT:Larson, Clarence Oak Ridge National Laboratory people 20th-century American chemists People from Cloquet, Minnesota University of Minnesota College of Science and Engineering alumni University of California, Berkeley alumni 1909 births 1999 deaths Members of the United States National Academy of Engineering Manhattan Project people