Harold G. Richter

Last updated
Harold G. Richter
Born
Harold Gene Richter

(1925-03-05)March 5, 1925
Fontanet, Indiana
DiedJuly 19, 2001(2001-07-19) (aged 76) [1]
Chapel Hill, North Carolina
NationalityAmerican
Alma mater Massachusetts Institute of Technology
Known forNuclear chemistry, Air and water quality measurement methods
Spouse(s)Marjorie Richter
Scientific career
Institutions Research Triangle Institute, United States Atomic Energy Commission, Environmental Protection Agency
Doctoral advisor Charles D. Coryell

Harold Gene Richter (March 5, 1925 - July 19, 2001) was an American chemist noted for his development of new analytical techniques for determination of water and air quality. Much of his career was spent at the Research Triangle Institute in Durham, North Carolina. Richter conducted research involving radioisotopes for the United States Atomic Energy Commission. He was a project officer for the Environmental Protection Agency, specializing in techniques for monitoring water and air quality. Richter developed new methods of analysis and monitoring during his tenure with both agencies.

Contents

Post-2000 sources suggesting that Richter had a role in the discovery of the element promethium in 1945 may be inaccurate. Earlier records, including Richter's own curriculum vitae of 1966, make no mention of such a connection. [2]

Childhood

Harold Gene Richter was born on March 5, 1925 in Fontanet, Indiana. [3] His parents were Leslie Earl Richter and Ola Rozella (Chandler) Richter.

Education

After serving in World War II, Richter attended Franklin College in Franklin, Indiana. He earned his B.A. in 1947. [3]

During 1947–1948, Richter worked as a Junior physicist with Nathan Sugarman at Argonne National Laboratory, resulting in the publication of works on the natural radioactivity of rhenium and short‐lived fission products of iodine, rubidium and cesium. [2] [4] [5]

From 1948 to 1952, Richter attended Massachusetts Institute of Technology (MIT), [2] completing his M.Sc. in 1950 and his Ph.D. in 1952, in the chemistry department. [6] Harold Richter studied with Charles D. Coryell at MIT, investigating nuclear chemistry. [2] He wrote his Ph.D. thesis on The Photofusion of Uranium (1952). [7] He published a scientific paper with Coryell on "Low-Energy Photofission Yields for U238" (1954). [8]

Career

In 1952 Richter joined the faculty of the University of Oregon in Eugene, Oregon, as an assistant professor of chemistry. [6]

In 1954–1955, Richter did classified work at the U. S. Naval Radiological Defense Laboratory, [2] at the Hunter's Point Naval Shipyard in San Francisco, California. [9] From 1955 to 1959, Richter worked for the Nuclear Science and Engineering Corporation in Pittsburgh, Pennsylvania [2] (later the International Chemical and Nuclear Corporation). At Nuclear Science and Engineering Corporation, he "developed new methods of radiochemical analysis and of low-level radioactivity techniques." [9]

In 1959 [2] Richter moved to the Isotope Development Laboratory of the Research Triangle Institute (RTI) in Durham, North Carolina, which was founded in 1958. Some of his work at RTI was carried out under contract to the Division of Isotopes Development of the United States Atomic Energy Commission. [10]

In 1964–1965, Richter received a Fulbright Award to conduct further scientific investigations at laboratories outside of the United States. [11] He was then in residence with the Section d’Application des Radioelements of the Centre d'Études Nucléaires in Grenoble, France. There he conducted radioisotope research and developed radio-release methods for tracing contaminants in stream flows. [12] [13]

Richter also served as a project officer for the Environmental Protection Agency of the United States. In the 1970s and 1980s, a major focus of his investigations was the development of techniques for analysis of water and air quality and subsequent use of the methods for investigation of water and air quality. [14]

Promethium

Early in the 20th century, Czech chemist Bohuslav Brauner, and later English physicist Henry Mosely, predicted the existence of an element with atomic weight 61, situated between neodymium and samarium on the periodic table. Various scientists had attempted to isolate the predicted element without success since the time of Mosely's and Brauner's predictions. [15]

Working in 1945, Charles D. Coryell, Lawrence E. Glendenin and Jacob A. Marinsky carried out experiments on isolation of the missing element. These experiments were conducted at Clinton Laboratories in Oak Ridge, Tennessee (officially renamed Oak Ridge National Laboratory in 1947). They obtained element 61 by two means, including as a nuclear fission product of uranium and the neutron bombardment of neodymium, all conducted in graphite reactors. This element was subsequently named "promethium", an inherently unstable element in all of its isotopic forms. [15]

Richter is not mentioned in contemporary sources that discuss the 1945 work on promethium conducted by Coryell, Marinsky, and Glendenin at Clinton Laboratories. [16] [17] According to Richter's 1966 curriculum vitae (published in a government report), his connection to MIT dated to 1948, after the discovery was made. Richter's cv does not mention Oak Ridge National Laboratory, Coryell, or promethium. His description of his Ph.D. work reads: [2]

"1948-1952. Massachusetts Institute of Technology, Cambridge,. Massachusetts. The Ph.D. degree required a detailed knowledge of radiochemical analytical techniques. At the same time, it afforded an opportunity to work with the high-energy accelerators then available at MIT (linear accelerator, synchrotron and cycloytron)." Harold Richter, 1966

Richter is listed as a co-discoverer of promethium in some post-2000 internet and print sources on the history of the elements and the discovery of promethium. [18] [19] [20] At least one of these sources has been criticized by reviewers for inaccuracies. [21] Encyclopædia Britannica notes that the existence of promethium was proved by Marinsky, Glendenin, and Coryell in 1945, but not publicly announced until 1947. [15] A photograph of Richter with Coryell, Glendenin and Marinsky, available on the internet, is undated and may reflect the period when Richter was a graduate student (1948-1952) rather than the 1945 discovery. [22]

Death

Harold G. Richter lived in Chapel Hill, North Carolina, with his wife Marjorie Richter. He died on July 19, 2001 [23] and is buried at Chapel Hill Memorial Cemetery. [1]

Selected works

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References

  1. 1 2 "077 CHAPEL HILL MEMORIAL CEMETERY [NEW] (CA. 1949) - Surname starts with R". Cemetery Census. Retrieved 28 December 2018.
  2. 1 2 3 4 5 6 7 8 Hansen, Richard Lee; Schuster, Jack C. (1966). Discharge Measurement Using Radioisotopes in High Head Turbines and Pumps. U.S. Atomic Energy Commission. p. 143. Retrieved 6 May 2020.
  3. 1 2 Alumni Association (2003). "MIT Class of 1950 The MidCentury Class". MIT. Retrieved 28 December 2018. In an earlier edition we noted the passing of Harold Gene Richter, SM on July 19, 2001 ... Born in Fontanet, IN, Harold served in World War II for two years before returning to Franklin College on Franklin, IN to obtain a BA in 1947. He worked in the Department of Chemistry at the University of Oregon for several years, before working in San Francisco at the Office of Naval Research at Hunters Point. His career lead him to the Research Triangle Institute in North Carolina, then later to CERN in Grenoble where he worked on radio isotopic research. He is survived by his wife, Marjorie; daughter, Melanie; sons Jeff, Kyle, and Tad, as well as five grandchildren.
  4. ↑ Sugarman, Nathan; Richter, Harold (1 June 1948). "Note on the "Natural Radioactivity of Rhenium"". Physical Review. 73 (11): 1411–1412. doi:10.1103/PhysRev.73.1411.2. hdl: 2027/mdp.39015086446500 . Retrieved 6 May 2020.
  5. ↑ Sugarman, Nathan; Richter, Harold (February 1950). "Short‐Lived Fission Products. II. Cs and Cs". The Journal of Chemical Physics. 18 (2): 174–178. doi:10.1063/1.1747582.
  6. 1 2 University of Oregon Bulletin Catalog Issue 1954-55-55 (PDF). Eugene, Oregon: University of Oregon. May 29, 1954. p. 107.
  7. ↑ Richter, Harold G. (1952). The photofusion of uranium (Dissertation, Ph. D. ed.). Cambridge, MA: Massachusetts Institute of Technology, Dept. of Chemistry.
  8. ↑ Richter, Harold G; Coryell, Charles D (1954). "Low-Energy Photofission Yields for U238" (PDF). Physical Review. 95 (6): 1550–1553. Bibcode:1954PhRv...95.1550R. doi:10.1103/PhysRev.95.1550.
  9. 1 2 Ely, Ralph L.; Richter, Harold G.; Gardner, Robin P. (1964). "Production and Use of Short-Lived Radioisotopes from Reactors, Volumes I and II". Nuclear Science and Engineering. 19 (2): 255–257. doi:10.13182/NSE64-A28922. Each of the reviewers is a member of the technical staff of the Research Triangle Institute, Durham, North Carolina ... Harold Richter was at the US Naval Radiological Defense Laboratory and at Nuclear Science and Engineering Corporation where he developed new methods of radiochemical analysis and of low-level radioactivity techniques.
  10. ↑ Richter, H. G.; Gillespie, A. S. (1965). "Radio Release Determination of Dichromate Ion in Natural Waters". Anal. Chem. 37 (9): 1146–1148. doi:10.1021/ac60228a019 . Retrieved 28 December 2018. RECEIVED for review April 15, 1965. Accepted May 24, 1965. Part of the work was carried out at the Research Triangle Institute, Durham, N. C., under U. S. Atomic Energy Commission, Division of Isotopes Developments Contract No. AT-(40-1)-2513. The remainder of the work was performed at le Centre d’Etudes Nucleaires de Grenoble, in the Section d’Application des Radioelements, where one of us (H. G. R.) was given the freedom to pursue the study, and records here his appreciation of the cooperation from that group. H. G. Richter also expresses his appreciation for a 1964-65 Fulbright Grant.
  11. ↑ Bureau of Educational and Cultural Affairs (1964). U. S. Grantee Directory (PDF). Washington, D.C.: Department of State. pp. 65, 258. Retrieved 29 December 2018.
  12. ↑ Richter, H. G. A Radiometric Method for Determination of Iodide In Natural Waters. Grenoble, France: Commissariat A l 'Energie Atomique, Centre d 'Etudes Nucleaires de Grenoble, Department des Radioelements. pp. 1–18.
  13. ↑ Richter, H. G. (May 1966). "A Radiometric Method for Determination of Iodide in Natural Waters". Analytical Chemistry. 38 (6): 772–774. doi:10.1021/ac60238a025.
  14. ↑ Dodge, Marcia C.; Richter, Harold G. (1991). "CHAPTER 3. PROPERTIES AND PRINCIPLES OF FORMATION OF CARBON MONOXIDE". U.S. EPA. Air Quality Criteria for Carbon Monoxide (Final Report, 1991) EPA/600/8-90/045F. Washington, DC: U.S. Environmental Protection Agency. p. xxviii.
  15. 1 2 3 Gregersen, Erik. "Promethium". Encyclopædia Britannica. Retrieved 6 May 2020.
  16. ↑ Marinsky, J. A.; Glendenin, L. E.; Coryell, C. D. (1947). "The chemical identification of radioisotopes of neodymium and of element 61". Journal of the American Chemical Society. 69 (11): 2781–5. doi:10.1021/ja01203a059. hdl: 2027/mdp.39015086506477 . PMID   20270831.
  17. ↑ "Discovery of Promethium" (PDF). Oak Ridge National Laboratory Review. 36 (1): 3. 2003. Retrieved 2018-06-17.
  18. ↑ Saunders, Nigel (2004). Uranium and the rare earth metals . Heinemann Library. p.  61. ISBN   9781403455000 . Retrieved 29 December 2018.
  19. ↑ Cobb, Harold M. (2012). Dictionary of metals. ASM International. p. 176. ISBN   9781615039784 . Retrieved 29 December 2018.
  20. ↑ Ede, Andrew (2006). The chemical element : a historical perspective. Westport, CT: Greenwood Press. ISBN   978-0313333040. Appendix 2 it was isolated in 1945 by the team of Charles D. Coryell, Jacob (Jack) A. Marinsky, Lawrence E. Glendenin, and Harold G. Richter. They identified promethium as one of the by-products of uranium fission
  21. ↑ Scerri, Eric R. (January 2007). "The Chemical Element: A Historical Perspective (Greenwood Guides to Great Ideas in Science) (Andrew Ede)". Journal of Chemical Education. 84 (1): 42. Bibcode:2007JChEd..84...42S. doi: 10.1021/ed084p42 .
  22. ↑ Trapp, Dave (16 June 2007). "Origins of the Element Names". The Chemical Elements. Retrieved 6 May 2020.
  23. ↑ Alumni Association (2002). "MIT Class of 1950 The MidCentury Class". MIT. Retrieved 28 December 2018. Two other classmates not listed in the Reunion Book who have passed away are Dr. Harold G. Richter on July 19. 2001 ... Harold's address is 8601 Little Creek Farm Road Chapel Hill, NC 27516 where he lived with his wife Marjorie Richter. He received both his MS and PhD from Course 5.
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