Xu Guangxian (Chinese: 徐光宪; November 7, 1920 – April 28, 2015), also known as Kwang-hsien Hsu, was a Chinese chemist. He was an academician of the Chinese Academy of Science who is respected for his contributions in both theoretical and experimental chemistry.[3][4] He is a former president of the Chinese Chemical Society, and is known as "The Father of Chinese Rare Earths Chemistry".[5][4]
In 1940 Xu entered Jiaotong University in Shanghai (now known as Shanghai Jiao Tong University, SJTU).[7] Again, there was disruption at the university because of the war.[8] Xu received his B.Sc. in 1944.[7] In 1945, Xu Guangxian worked as a teaching assistant at SJTU, with professor Gu Jidong.[7]
He married one of his classmates, chemist Gao Xiaoxia in 1946.[9]
Xu and Gao passed national examinations for studying abroad in 1946. Xu traveled to the United States in 1948 to attend the graduate school of Washington University in St. Louis. After ranking first in a probationary summer class at Columbia UniversityinNew York City, he was able to transfer to Columbia.[2] There he studied quantum chemistry with a minor in physics from 1948 to 1951.[3] He also worked as a teaching assistant, enabling Gao Xiaoxia to join him and study analytical chemistryatNew York University.[2]
Xu received his MS in 1949 and his PhD in 1951[10][11] working with Charles O. Beckmann.[12] His thesis in quantum chemistry was "Optically Active Quantum Chemical Theory".[2] In February 1949, he became a member of the Phi Lambda Upsilon National Honorary Chemical Society (ΦΛΥ). In October 1950, Xu became a member of Sigma Xi (ΣΞ).[2]
Meanwhile, in China, the Chinese Civil War resulted in the formation of the People's Republic of China in 1949. The Korean War broke out in June, 1950. Soon after, the United States government passed an act forbidding Chinese citizens who were studying in America from returning to China.[13] Concerned that they might not be allowed to return home if they waited until Gao Xiaoxia received her Ph.D., Xu Guangxian and Gao Xiaoxia applied for short-term visas to China. On April 15, 1951, they left for China on the USS General Gordon, one of the last three cruisers to leave for China before the American ban went into effect.[7]
After returning to China in 1951, Xu became an associate professor at the Department of Chemistry of Peking University. By autumn 1952, he held professorships in both the Department of Chemistry and the Department of Technical Physics. Xu held various directorships at the university. He worked primarily in the areas of quantum chemistry and chemical bonding theory. He studied the bonding characteristics of molecules and proposed a formula relating the order of filling of atomic orbital levels to the grouping of elements into periods in the periodic table. This led to greater understanding of the lanthanides and actinides.[3]
Xu became the department dean in 1956 and directed the department of radiation chemistry.[14] Xu was involved in the Chinese nuclear weapons development program, in which he played a role in separating and extracting elements for nuclear fuels. In particular, he did experimental research on the separation of Uranium-235 and Uranium-238.[14][15] After 1966, when the Cultural Revolution began, Xu's department stopped doing atomic research.[16]
When he returned to Peking University in 1972, Xu was asked to change his field of study to the extraction of praseodymium, a rare earth element.[12][3] During the 1970s, Xu studied the theoretical basis and design for solvent extraction, developed mathematical models, and made important contributions towards the development of separation processes for rare earth elements.[16][17][18] Gao Xiaoxia's development of microanalytical techniques in polarography contributed to the success of Xu's research.[16][12] Xu developed the process of countercurrent extraction (also known as series extraction or cascade extraction)[12][16] and substantially reduced both the time needed to extract materials, and their resulting cost.[14]
Xu founded the Research Center of Rare Earth Chemistry as of 1986 and was essential in establishing the State Key Laboratory of Rare Earth Materials Chemistry and Applications in 1989.[4][3] He served as director and as chairman of its academic committee.[3][19]
In 2005, Xu Guangxian raised concerns about the mining of thorium in the Baotou area, where mine wastes were released into the Yellow River.[16][20] The Yellow River is a source of drinking water for an estimated 150 million people, so radioactive contamination is a very serious issue.[21] Xu has suggested that the Chinese develop stocks of rare earths to stave off shortages of rare earths.[22]
Xu published more than 500 reviewed papers[3] and several books. These included Principle of Extraction Chemistry, Rare Earth Solvent Extraction, The Structure of Matter and The Basic Principles of Quantum Chemistry and Ab-initio Calculation.[3] Xu has supervised hundreds of students.[12]
In 2009, Xu Guangxian, Qian Xuesen, Zhang Guangdou, and Wu Wenjun were honored with the inaugural SJTU Outstanding Alumni Lifetime Achievement Award from Shanghai Jiao Tong University.[23][2]
Vice-president (1980―1999), Chinese Society of Rare Earths (CSRE)[3][28] Honorary vice-president thereafter[3]
Editor-in-chief, Rare Earths (a 3-volume monograph on the science and technology of rare earths in China), Metallurgical Industry Press, Beijing, 1995[29]
^Yelong Han (1993). "An Untold Story: American Policy toward Chinese Students in the United States, 1949–1955". The Journal of American-East Asian Relations. 2 (1 (Special Issue: The Impact of the Korean War)): 77–99. doi:10.1163/187656193X00095. JSTOR23612667.
^Xu Guangxian (October 20, 2005). "An Emergency Call for the Protection of Thorium and Rare Earth Resources at Baiyun Erbo and the Prevention of Radioactive Contamination of the Yellow River and Baotou". Chinese Academy of Sciences. {{cite journal}}: Cite journal requires |journal= (help)