Obituaries

James L. Krevel, 70, a retired industrial chemist, died on Jan. 21 in West Chester, Pa.

Krevel received a bachelor's degree in mathematics from Franklin & Marshall College, in Lancaster, Pa., in 1959. He later earned master's degrees in mathematics and chemistry from Villanova University in Pennsylvania. He served in the Marine Corps and Marine Corps Reserves.

He spent his career as a chemist for Foote Mineral, in Exton, Pa., and in Charlotte, N.C., until his retirement in 1996. He joined ACS in 1965.

He is survived by his brother, Gerald, and his companion, Marthena Scollon. Krevel's wife, Harriet, and brother, Donald, predeceased him.

Sister Rita Marie Mueller, 90, a retired professor of chemistry at Thomas More College, in Crestview Hills, Ky., died on Sept. 6, 2008, in Covington, Ky.

Born in Cincinnati, Mueller entered the order of the Sisters of Notre Dame in 1936, taking the name Sister Mary Casimira until the order permitted a return to given names in the 1980s.

She enrolled at Villa Madonna College (now Thomas More College) in 1937, earning bachelor's degrees in both physics and mathematics. Subsequently, she earned an M.S. degree from Catholic University of America and a Ph.D. from the University of Cincinnati, both in chemistry.

Mueller taught general chemistry, physical chemistry, and quantum mechanics for many years at Thomas More. She was the chair of its chemistry department for 15 years. Under her leadership, the department established a co-op program for chemistry students. She later obtained a grant to extend co-op opportunities to the entire college and served as the first director of the expanded program.

Mueller also served as director of institutional research for the college. She retired in 2004, after being associated with the college for more than 67 years. She celebrated the 70th jubilee of religious profession the month before she died.

She was an emeritus member of ACS, joining in 1959.

Survivors include her brother, Jerome, and two sisters, Theresa Miller and Sister Ellen Mueller.

Luis G. Roldan, 83, a research chemist, died at home on Feb. 1 in Greer, S.C., after a battle with Alzheimer's disease.

Roldan was born in GarafÍa, on the Canary Islands, and raised in Seville, Spain, where he obtained his doctorate degree in chemistry and crystallography at the University of Seville in 1957.

He moved to the U.K. to begin work in industrial research at British Rayon; he later worked for Allied Chemical, in Morristown, N.J. In 1968, he began an 18-year stint at J. P. Stevens, working first in Garfield, N.J., and then at the company's Greenville, S.C., research and development facility.

After retiring from J. P. Stevens in 1986, Roldan worked for the National Institute of Standards & Technology, certifying laboratories for asbestos testing. He also worked as a professor and dean at the University of Beira Interior, in Covilhã, Portugal, and as an adjunct professor at North Carolina State University.

An expert in using X-ray diffraction and electron microscopy in the field of material science, Roldan published more than 40 articles in scientific journals. He joined ACS in 1962.

He is survived by his wife of 48 years, Carmen; four children, José, Luis, Mary, and Carlos; and three grandchildren.

Donald E. Woessner, 78, a renowned nuclear magnetic resonance spectroscopist, died on Nov. 3, 2008, in Dallas as a result of a stroke suffered in May.

"No one knows more about nuclear magnetic resonance relaxation than Don Woessner," the late Nobel Laureate Paul C. Lauterbur once said. Woessner was an expert in that area, which refers to the time it takes for excited nuclei to return to the ground state.

Born in Milledgeville, Ill., Woessner received an A.B. degree in chemistry in 1952 from Carthage College, in Kenosha, Wis. He then earned a Ph.D. in physical chemistry in 1957 at the University of Illinois, Urbana-Champaign, working with NMR pioneer Herbert Gutowski.

After a one-year postdoctoral stint with Gutowski, he began a long career in the Field Research Laboratory of Mobil Research & Development, in Dallas.

In his early work, Woessner helped to build ground-breaking equipment and develop theory to measure and understand NMR relaxation. His 1962 Journal of Chemical Physics paper focusing on what are now known as the Woessner equations (1962, 37, 647) was later recognized as a Science Citation Classic, a highly cited publication as identified by the Science Citation Index. Woessner often collaborated with visiting scientists in the areas of biological, biochemical, and medical research.

After retiring from Mobil in 1992, Woessner served as an adjunct professor at the Advanced Imaging Research Center at the University of Texas Southwestern Medical School, Dallas.

He was the author of 84 scientific publications in chemistry and biology. He served on the editorial boards of the Journal of Chemical Physics and the Journal of Magnetic Resonance.

He was an emeritus member of ACS, joining in 1962. He received the ACS Dallas-Fort Worth Section's Wolfred T. Doherty Award in 1971 and the ACS Southwest Regional Award in 1991. He also served the Dallas-Fort Worth Section as secretary, treasurer, and chair.

He is survived by his wife of 50 years, Rebecca; a son, Richard; and two grandchildren.

John T. Yoke III, 80, professor emeritus of chemistry at Oregon State University, died on Feb. 12.

Yoke received a B.S. from Yale University in 1948 and a Ph.D. in inorganic chemistry from the University of Michigan. He served in the Army Chemical Corps before working for Procter & Gamble as a research chemist. He was on the faculties of University of North Carolina and the University of Arizona before joining Oregon State in 1964. His research emphasized phosphorus chemistry and reactions of phosphorus and nitrogen ligands in metal complexes. He retired in 1990.

Yoke was an emeritus member of ACS, joining in 1949. He served as chair of the ACS Southern Arizona Section in 1964.

He is survived by his wife, Mary Alice; three children, John, James, and Mary; and three grandchildren.