James Andrew Harris
|Born||March 26, 1932|
|Died||December 12, 2000 68)(aged|
|Co-discovery of rutherfordium and dubnium|
James Andrew Harris (March 26, 1932 – December 12, 2000) was a nuclear chemist who was involved in the discovery of elements 104 and 105 (rutherfordium and dubnium, respectively). Harris is known for being the first African American to contribute to the discovery of new elements.
James A. Harris was born on March 26, 1932 in Waco, Texas.Harris' parents divorced when he was young, after which he moved to Oakland, California with his mother and attended high school. Harris met his wife Helen at Huston-Tillotson College, where they were both completing their undergraduate studies; they were married in 1957 and had five children, Cedric, Keith, Hilda, Kimberly, and James II. Between the time of his graduation from college and his marriage, Harris served in the Army. His hobbies included golf, traveling, and community activities. James A. Harris died of a sudden illness on December 12, 2000.
James A. Harris attended McClymond High School in Oakland, California. After high school, Harris returned to Texas where he attended Huston-Tillotson College in Austin.He studied chemistry and received a bachelor of science degree in 1953. In 1975, Harris received a master's degree in Public Administration at California State University, Hayward. Harris was awarded an honorary doctorate from Huston-Tillotson College in 1973 for his co-discovery of rutherfordium and dubnium. Harris was also a brother of Alpha Phi Alpha fraternity.
Harris' first job in chemical research was at Tracerlab Inc. as a radiochemist; he worked there for five years. After that time, Harris left Tracerlab Inc. to work on the Nuclear Chemistry department of the Lawrence Radiation Laboratory at University of California-Berkeley working on isotope division.In 1977, Harris was promoted to head of the Head of Engineering and Technical Services Division at Lawrence. Harris retired from his work in the lab in 1988.
Harris worked in the Heavy Isotopes Production Group. His job was to design and purify targets that would be used to discover elements 104 and 105. These targets needed minimal impurities of elements such as lead to work.Harris' colleagues praised his work, saying that it was high quality and good for elemental research.
Two research teams were simultaneously working to discover elements 104 and 105. One was Harris's team at the University of California-Berkeley and the other was a team of Russian scientists. Both teams successfully isolated the two elements around the same time, so there is dispute over which team was actually the first to isolate the elements. To ease the dispute, element 104 was given the name suggested by the American research team, rutherfordium, after the influential British physicist. Element 105 was subsequently given the name dubnium, representing the city where the Russian team worked.
Harris worked on the following organizations:
Bohrium is a synthetic chemical element with the symbol Bh and atomic number 107. It is named after Danish physicist Niels Bohr. As a synthetic element, it can be created in a laboratory but is not found in nature. All known isotopes of bohrium are extremely radioactive; the most stable known isotope is 270Bh with a half-life of approximately 61 seconds, though the unconfirmed 278Bh may have a longer half-life of about 690 seconds.
Dubnium is a synthetic chemical element with the symbol Db and atomic number 105. Dubnium is highly radioactive: the most stable known isotope, dubnium-268, has a half-life of about 28 hours. This greatly limits the extent of research on dubnium.
Glenn Theodore Seaborg was an American chemist whose involvement in the synthesis, discovery and investigation of ten transuranium elements earned him a share of the 1951 Nobel Prize in Chemistry. His work in this area also led to his development of the actinide concept and the arrangement of the actinide series in the periodic table of the elements.
Lawrencium is a synthetic chemical element with the symbol Lr and atomic number 103. It is named in honor of Ernest Lawrence, inventor of the cyclotron, a device that was used to discover many artificial radioactive elements. A radioactive metal, lawrencium is the eleventh transuranic element and is also the final member of the actinide series. Like all elements with atomic number over 100, lawrencium can only be produced in particle accelerators by bombarding lighter elements with charged particles. Thirteen isotopes of lawrencium are currently known; the most stable is 266Lr with a half-life of 11 hours, but the shorter-lived 260Lr is most commonly used in chemistry because it can be produced on a larger scale.
Rutherfordium is a synthetic chemical element with the symbol Rf and atomic number 104, named after New Zealand physicist Ernest Rutherford. As a synthetic element, it is not found in nature and can only be created in a laboratory. It is radioactive; the most stable known isotope, 267Rf, has a half-life of approximately 1.3 hours.
Seaborgium is a synthetic chemical element with the symbol Sg and atomic number 106. It is named after the American nuclear chemist Glenn T. Seaborg. As a synthetic element, it can be created in a laboratory but is not found in nature. It is also radioactive; the most stable known isotope, 269Sg, has a half-life of approximately 14 minutes.
A synthetic element is one of 24 chemical elements that do not occur naturally on Earth: they have been created by human manipulation of fundamental particles in a nuclear reactor or particle accelerator, or explosion of an atomic bomb; thus, they are called "synthetic", "artificial", or "man-made". The synthetic elements are those with atomic numbers 95–118, as shown in purple on the accompanying periodic table: these 24 elements were first created between 1944 and 2010. The mechanism for the creation of a synthetic element is to force additional protons onto the nucleus of an element with an atomic number lower than 95. All synthetic elements are unstable, but they decay at a widely varying rate: their half-lives range from 15.6 million years to a few hundred microseconds.
The transuranium elements are the chemical elements with atomic numbers greater than 92, which is the atomic number of uranium. All of these elements are unstable and decay radioactively into other elements.
The names for the chemical elements 104 to 106 were the subject of a major controversy starting in the 1960s, described by some nuclear chemists as the Transfermium Wars because it concerned the elements following fermium on the periodic table.
Copernicium is a synthetic chemical element with the symbol Cn and atomic number 112. Its known isotopes are extremely radioactive, and have only been created in a laboratory. The most stable known isotope, copernicium-285, has a half-life of approximately 28 seconds. Copernicium was first created in 1996 by the GSI Helmholtz Centre for Heavy Ion Research near Darmstadt, Germany. It is named after the astronomer Nicolaus Copernicus.
Albert Ghiorso was an American nuclear scientist and co-discoverer of a record 12 chemical elements on the periodic table. His research career spanned six decades, from the early 1940s to the late 1990s.
Group 4 is a group of elements in the periodic table. It contains the elements titanium (Ti), zirconium (Zr), hafnium (Hf) and rutherfordium (Rf). This group lies in the d-block of the periodic table. The group itself has not acquired a trivial name; it belongs to the broader grouping of the transition metals.
Huston–Tillotson UniversityHTU) is a private historically black university in Austin, Texas. Established in 1875, Huston–Tillotson University was the first institution of higher learning in Austin. The university is affiliated with the United Methodist Church, the United Church of Christ, and the United Negro College Fund. Huston–Tillotson University awards bachelor's degrees in business, education, the humanities, natural sciences, social sciences, science, and technology and a Master's degree in educational leadership. The university also offers alternative teacher certification and academic programs for undergraduates interested in pursuing post-graduate degrees in law and medicine.
In chemistry, superheavy elements, also known as transactinide elements, are the chemical elements with atomic numbers greater than 103. The superheavy elements are located immediately beyond the actinides in the periodic table; the heaviest actinide is lawrencium.
Rutherfordium (104Rf) is a synthetic element and thus has no stable isotopes. A standard atomic weight cannot be given. The first isotope to be synthesized was either 259Rf in 1966 or 257Rf in 1969. There are 16 known radioisotopes from 253Rf to 270Rf and 4 isomers. The longest-lived isotope is 267Rf with a half-life of 2.5 hours, and the longest-lived isomer is 261mRf with a half-life of 81 seconds.
Dubnium (105Db) is a synthetic element, thus a standard atomic weight cannot be given. Like all synthetic elements, it has no stable isotopes. The first isotope to be synthesized was 261Db in 1968. The 13 known radioisotopes are from 255Db to 270Db, and 1–3 isomers. The longest-lived known isotope is 268Db with a half-life of 29 hours.
Larned (Larry) Brown Asprey was an American chemist noted for his work on actinide, lanthanide, rare-earth, and fluorine chemistry, and for his contributions to nuclear chemistry on the Manhattan Project and later at the Los Alamos National Laboratory.
Dawn Angela Shaughnessy is an American radiochemist and principal investigator of the heavy element group at the Lawrence Livermore National Laboratory. She was involved in the discovery of five superheavy elements with atomic numbers 114 to 118.
Pirkko Eskola is a Finnish physicist. She discovered the chemical elements Rutherfordium and Dubnium whilst working at the Lawrence Berkeley National Laboratory.