ACS Award in Nuclear Chemistry
Previous ACS Nuclear Chemistry Award
Recipients
Although radiochemistry programs have been dwindling at universities
across the U.S., exploration of the field is expanding at the
University of Missouri, Columbia, largely because of the efforts of
chemistry professor Silvia S. Jurisson.
When Jurisson
arrived at the university in 1991, attracted by its research reactor,
she was the department's only radiochemist.
''We now have four in the
chemistry department," she says.
"Regretfully, there has been a
precipitous decline in the number of academic nuclear and
radiochemistry programs in the U.S. over the last
25 years," says J. David
Robertson, a professor of chemistry and associate director of the
research reactor at the University of Missouri.
"Professor Jurisson provided
both the vision and the leadership that persuaded the university to
buck the national trend and invest in this area of critical national
need."
In addition, Jurisson sees teaching
-
to enable graduate and undergraduate students to spread their wings in
radiochemistry
-
as vital to her mission. "It is
really important to train the next generation of students in
radiochemistry and nuclear chemistry," she says.
"It is a field not as many
folks go into anymore."
Radioenvironmental chemistry and
radiopharmaceutical chemistry are two of Jurisson's main areas of
research. Her work in radioenvironmental chemistry has focused on
technetium-99, an isotope produced in the nuclear fuel cycle that has
a long half-life. Nuclear sites
that were active during the Cold War, such as Savannah River in South
Carolina and Hanford in Washington, have been contaminated with
99Tc. The most common
chemical form of the isotope, pertechnetate, isn't absorbed by most
clays in soil and thus tends to migrate in the environment.
Jurisson has sought to find a way to make 99Tc stop
migrating. She has attempted to
do this by reducing the pertechnetate with iron(II) sulfide.
''When we reacted that with the
pertechnetate, the technetium incorporated onto the surface of the
iron sulfide and bound there quite nicely," she recalls.
In radiopharmaceuticals, Jurisson's work has mostly been involved
with radiotherapy. There, the
objective Jurisson is to chelate radioactive metals such as rhenium,
rhodium, and radio-lanthanides and covalently link the chelates onto
antibodies or peptides. Rhenium
and technetium can directly cyclize peptides by coordinating to
cysteine thiolates from reduced disulfide bonds, as in the case of
a-melanocyte-stimulating
hormone or octreotide analogs. A
successful radiopharmaceutical will bind to the receptors of cancer
cells and, in Jurisson's words, "stay there long enough to irradiate
and hopefully kill them."
Recently, Jurisson's group has
been working on processing, separating, and complexing rhodium-105,
rhenlum-186, and arsenic-72. Her
group is now working on conjugating these radionuclides with peptides.
Jurisson, who is 55, says she has always been interested in math
and science and that her interest in chemistry in particular emerged
when she received a chemistry set as a child.
She earned a B.S. degree in
chemistry from the University of Delaware in 1978 and a Ph.D. in
inorganic chemistry from the University of Cincinnati in 1982.
She has authored 103 papers.
Jurisson will present the award address before the ACS Division of
Nuclear Chemistry & Technology.
ALEX TULLO,
Chemical & Engineering News, January 16, 2012, 90, 40-41.
2011 Glenn T.
Seaborg Nuclear Chemistry Award
David J. Morrissey has made a career of studying exotic, rare, and
short-lived nuclei and developing techniques to separate these nuclei
from thousands of other nuclear reaction products.
Morrissey
is one of the most important early leaders who recognized the
potential of the projectile fragmentation technique to produce and
study rare isotopes, colleagues say.
The University
Distinguished Professor of Chemistry and associate director of the
National Superconducting Cyclotron Laboratory (NSCL) at Michigan State
University, Morrissey is an expert in the mechanics of
intermediate-energy, heavy-ion reactions; the production of rare
isotopes from such reactions; and the application of those isotopes
for spectroscopic studies.
Most
recently, he has made significant contributions to the chemistry and
physics involved in stopping fast-moving heavy ions in gases.
“In a way, the production of
new or previously unobserved isotopes goes back to the earliest work
of nuclear scientists, the Curies and Rutherford,” he notes.
“Over
the past 100 years, the original 300 or so stable isotopes were
rapidly identified by mass spectrometry and then reacted with one
another to produce new nuclei.
These
studies have now progressed to the point that we have begun to firmly
establish upper and lower limits to the mass numbers for chemical
elements. The
task now is to investigate the reaction mechanism or develop new
instruments for separation and detection of the most exotic nuclei.”
Morrissey, 57,
received a B.S. in chemistry with distinction from Pennsylvania State
University in 1975 and a Ph.D. in chemistry in 1978 from the
University of California, Berkeley.
While he was
studying at Penn State, his interest shifted between chemistry and
physics, eventually settling on nuclear chemistry and conducting
undergraduate research with nuclear chemist Warren Miller.
Morrissey's
Ph.D. work was completed under the direction of Glenn T. Seaborg.
“Seaborg was a true pioneer in the discovery of both unknown chemical
elements and isotopes,” Morrissey notes.
“He
was always optimistic about going beyond what had already been
achieved, and it is interesting that only today we are beginning to
see real limits to the sizes of nuclei and distribution of neutrons
and protons in a nucleus.”
Morrissey
continued at UC Berkeley as a postgraduate fellow working with Luciano
G. Moretto.
Morrissey
began his faculty appointment at Michigan State and his association
with NSCL in 1981.
He
played a leading role in the evolution of NSCL into a world-leading
facility for the production and study of rare isotopes.
Morrissey was also
a member of the education team that developed the Computer-Assisted
Personalized Approach (CAPA) for assignments and examinations at
Michigan State, where he adapted CAPA to large freshman chemistry
classes. CAPA
has evolved and expanded to many U.S. universities.
Morrissey
is also coauthor of “Modern Nuclear Chemistry,” the text used in most
U.S. undergraduate nuclear chemistry courses.
One of Morrissey's
favorite activities has been what he calls “cosmopolitan travel”
-visiting large cities in Europe, Japan, Canada, and the U.S and
sampling their museums and sights, an attractive “side benefit,” he
notes, of the international nature of nuclear science.
Morrissey will
deliver the award address before the Division of Nuclear Chemistry &
Technology. – JEFF JOHNSON
C&EN, 89, February 7, 2011, 40-41
2010
Glenn T. Seaborg Nuclear Chemistry Award
|
 |
Lee Sobotka
Department of Chemistry
Washington University in St. Louis
Campus Box 1134
One Brookings Drive
St. Louis, MO 63130-4899 |
On
his departmental Web page, Lee G. Sobotka, 54, professor of chemistry and
physics at Washington University in St. Louis, describes his research focus as
"understanding, detecting and innovative uses of God's Quantum Dots." Those who
nominated the award winner get more down to Earth
when describing his development of novel technologies to attack important and
difficult problems in basic nuclear science.
For example, Sobotka and
D.G.
Sarantites developed the Dwarf-Ball and DwarfWall devices that allowed
the first measurement with full an coverage for the emitted charged particles,
for example, protons, deuterons, tritons, and
a particles, that didn't require forfeiting the ability to measure
photons or neutrons in a surrounding device. This accomplishment required
Sobotka to advance both detector technology and signal-processing electronics.
Another example resulted from his recognition that the existing microcircuits
built on Si chips for analog pulse-processing designed for high-energy physics
applications did not have the necessary features for their work. Sobotka and
coworkers Jon Elson and George Engel set to work making some that did. These
microelectronics facilitate the operation of 1,000+ element Si arrays for the
detection of ionizing radiation. This technology enabled Sobotka and his close
collaborator Robert Charity to perform many-particle correlation experiments and
thereby study the continuum structure oflight nuclei by particle-decay
spectroscopy. This includes, for example, the continuum structure or resonances
of very exotic nuclei such as JOC and, he reports most recently,
8e. Half a dozen groups around the
world are gearing up to use this technology.
These successes motivated Sobotka's team to develop another generic chip for
pulse-shape analysis, one with the ability to tell the type ofimpinging
radiation as well as its energy for certain scintillators. Although this chip is
still undergoing testing, groups at Michigan State University and Los Alamos
National Laboratory are planning to use it for basic nuclear science experiments
and for homeland security applications, respectively. Sobotka also has a
long-standing interest in the density of states (DoS) of the nuclear "quantum
dot." His interest focuses on how the DoS increases with excitation energy and
is affected by the neutron-proton asymmetrywith the attendant change in the
in-medium (nucleon-nucleon) correlations with changing neutron-to-proton ratio.
Sobotka received a bachelor's degree in chemistry from the University of
Michigan -c in 1977 joined the faculty of Washington University in St. is Louis
in 1984 and has made it his professional home. A colleague sums up Sobotka's
attributes: "While many scientists meld technology, experimentation, and nuclear
modeling, Sobotka has spliced these together to an unrivaled degree. He
attributes this to a mind-set of doing what has to be done, when it has to be
done, with the resources one can realistically expect to have, while engaging
like-minded collaborators who enjoy, as he does, all aspects of the science of
discovery." Sobotka will present the award address before the Division of
Nuclear Chemistry & Technology.-LlNDA RABER
2009 Glenn T.
Seaborg Nuclear Chemistry Award
|
 |
Kenton (Ken) J. Moody
Lawrence Livermore National Laboratory
7000 East Avenue
Livermore, CA 94550 |
from Chemical & Engineering News, February 2, 2009 - Volume 87, Number
5, p. 40
Mitch Jacoby
For chemists who work in heavy-element
synthesis, discovering a new element can be
the highlight of a scientific career.
Kenton J. Moody, a staff
chemist at Lawrence Livermore National
Laboratory, enjoys the distinction of having
discovered not one, but five new elements.
As a founding member of the collaboration
between the heavy-element research groups at
Livermore and the Flerov Laboratory of
Nuclear Reactions, in Dubna, Russia, Moody
served as a senior member of the teams that
discovered elements 113, 114, 115, 116, and
118. Those seminal investigations also led
to the first observations of more than 30
isotopes of various heavy elements.
"There are very few people who can claim
to have participated in the discovery of
even one new chemical element," says Dawn A.
Shaughnessy, a staff chemist at Livermore.
"Playing an active role in the discovery of
five new elements is a remarkable
accomplishment."
Shaughnessy points out that Moody was a
graduate student with the late chemistry
Nobel Laureate Glenn T. Seaborg and that,
like his mentor, Moody dedicated his career
to nuclear chemistry. In particular, Moody
helped collect a growing body of
experimental evidence for the existence of
the "island of stability," a region on the
chart of nuclides in which certain
superheavy nuclei are predicted to be
especially stable. Verifying the island's
existence was critically important to
Seaborg.
Moody's contributions to the field are
memorialized on new periodic tables and will
be recognized in textbooks used by future
chemistry students, Shaughnessy says. All of
those accomplishments, she comments, make
Moody's receipt of the Seaborg Award "most
appropriate."
Moody, 54, has focused on research in
nuclear chemistry since the 1970s. He has
investigated a wide range of topics in
nuclear and radiochemistry, including
heavy-element synthesis and detection,
characterization of actinide and
transactinide elements, and measurement of
nuclear reaction cross sections
(probabilities). He has also developed
methods for chemical separations and
analysis of most of the elements in the
periodic table.
Among Moody's more recent contributions
to nuclear science is his creation of the
new discipline of nuclear forensics, for
which he is coauthor of the field's
definitive textbook. To help set this new
area of science on solid ground, Moody
developed the methodology needed to deduce
the history of samples of nuclear materials.
This technique is now routinely used by the
Department of Homeland Security and
law-enforcement agencies to identify illicit
nuclear materials.
Moody graduated in 1977 with a bachelor's
degree in chemistry from the University of
California, Santa Barbara, and received a
Ph.D. in nuclear chemistry from UC Berkeley
in 1983. After conducting postdoctoral
research in the Nuclear Science Division of
Lawrence Berkeley National Laboratory, Moody
moved to Germany, where he was appointed
staff scientist at the Institute for Heavy
Ion Research, in Darmstadt. In 1985, he
returned to the U.S. to begin a position as
a nuclear chemist at Livermore and has
continued to conduct research there for
nearly 25 years.
Moody has published more than 100 papers
in scientific journals and has mentored
numerous summer research interns and
graduate students. He has also served as an
instructor for the ACS summer school in
nuclear chemistry, lecturing on
heavy-element science, fundamentals of
radiochemistry, and nuclear forensics.
Moody's commitment to nuclear science
education has recently led to his
appointment as adjunct professor in the
newly formed radiochemistry program at the
University of Nevada, Las Vegas.
Moody will present the award address
before the Division of Nuclear Chemistry &
Technology
2008 Glenn T.
Seaborg Nuclear Chemistry Award
from Chemical & Engineering News, January 21, 2008 - Volume 86, Number
3
Romualdo T. de Souza, the son of an American oil company engineer, was
born in India in 1963. When he was six, his family relocated to Dubai, United
Arab Emirates, where they lived for four years before immigrating to the U.S. De
Souza grew up in the late 1960s, and his passion for science and engineering was
ignited by the Apollo space program and the race to put a man on the moon.
De Souza, professor of chemistry at Indiana University, Bloomington, is now a
leading researcher in the field of nuclear reaction dynamics. The award winner
has been selected for his work in elucidating the nature of nuclear
multifragmentation through the use of fragment-fragment velocity correlations
and developing key instrumentation enabling research in nuclear chemistry.
"Professor de Souza is a true scholar doing cutting-edge research in the
field of nuclear chemistry," says David F. Clemmer, Robert & Marjorie Mann Chair
of Chemistry at Indiana University. "The insight, ambition, and energy that
Professor de Souza brings to his science are remarkable," Clemmer says.
Receiving this horror, however, was a bit of a surprise for de Souza. "It is
gratifying to have the work that you feel so passionately about recognized by
colleagues in the field," he says. He adds that winning this award is
particularly meaningful as many of his scientific role models arc former Seaborg
Award recipients.
De Souza's research deals with nuclear reactions involving a single collision
of two nuclei. The collision yields a highly excited nuclear system that rapidly
decays into multiple protons, neutrons, and larger clusters. This phenomenon is
known as multifragmentation.
"This technique of fragment-fragment correlations utilizes the interaction
between the particles themselves to assess the spatial and temporal extent of
the decaying source on the timescale of less than 10-21 seconds," de
Souza explains. With this approach, his group has been able to show that
multifragmentation is an evolutionary process and does not involve an
instantaneous breakup of a highly excited system into multiple fragments as
previously thought.
De Souza's research also included the development of sophisticated
instrumentation capable of yielding high isotope and angular resolution.
Specifically, he has played a key role in developing 4p detectors and silicon
strip arrays.
In addition to his research contributions, de Souza has been active in
improving chemical education. For example, in 1996, he developed the Computer
Assisted Learning Method (calm.indiuna.edu), which is a Web-based learning
environment that is now being used by more than 2,000 first-year chemistry
students at Indiana University’s Bloomington campus.
"Professor de Souza brings to his research an energy and intellect that has
enriched not only our knowledge of the interactions between complex nuclei but
also the broader scientific community through his initiatives in instrumentation
and chemical education," says Claus-Konrad Gelbke, director of the National
Superconducting Cyclotron Laboratory (NSCL) at Michigan State University.
Prior to joining Indiana University in 1991, de Souza, 44, completed a
postdoc appointment at the University of Rochester and a research assistantship
at NSCL. He holds Ph.D. and M.S. degrees from the University of Rochester 1988
and 1985, respectively and an A.B. from Washington University, St. Louis (1983).
De Souza was an SBC Fellow in 2003 and an Ameritech Fellow in 2002. He is a
member of ACS, the American Association for the Advancement of Science, the
American Physical Society, and Sigma Xi.
The award address will be presented before the Division of Nuclear Chemistry
& Technology at the fall 2008 national meeting in Philadelphia.--SUSAN
MORRISSEY
2007 Glenn T.
Seaborg Nuclear Chemistry Award
from Chemical & Engineering News, February 15, 2007 - Volume 85, Number
3
Norbert G. Trautmann, 67, had the benefit of professional contact with
Glenn T. Seaborg and Otto Hahn at formative stages in his career. While working
for his Ph.D. in nuclear chemistry at Johannes Gutenberg University, Mainz, in
Germany, Trautmann was part of a group that discovered the heaviest isotopes of
protactinium. Hahn, who discovered protactinium with Lise Meitner, took an
interest in this work when he occasionally visited his partner in splitting the
atom, Fritz Strassmann, Trautmann still at Mainz in the 1960s. "He also dropped
in on my lab and asked what was going on with protactinium," Trautmann recalls.
After receiving his Ph.D., Trautmann initiated work on fast chemical
separation methods, mainly based on solvent extractions. The methods had to
separate a single element from a mixture 30 or more elements in fission product
mixtures and perform the separation quickly enough to accommodate the sometimes
subsecond half-lives of the isotopes of the isolated elements. In 1970, Seaborg
became interested in the fast-separation techniques that Trautmann was
developing and invited him to come to Lawrence Berkeley National Laboratory
(LBNL), where he worked in 1970 and 1971 under Seaborg and Albert Ghiorso.
Trautmann recalls Seaborg fondly. "At that time, you could ask him more or less
anything about the heaviest elements," Trautmann says. "I admired him very
much."
Gerhardt Friedlander, a retired senior chemist with Brookhaven National
Laboratory, says Seaborg himself would be impressed by Trautmann's body of work,
noting that "Trautmann coauthored several publications with him and has
contributed significantly to the field closest to Seaborg's heart: production
and properties of the heaviest elements."
Following his fellowship at LBNL, Trautmann returned to Mainz, where he
became the deputy manager of the Research Reactor TRIGA Mainz at the Institute
for Nuclear Chemistry (INC). He became the manager of the research reactor in
1991, a position he gave up only a few months ago.
Friedlander recalls, from visits to INC, Trautmann's boundless energy. "He
really seems to be the one who keeps all the wheels in the institute turning,"
he says. "His nonstop work habits are legendary. Time and time again, I have
seen experiments and projects on the verge of foundering until Trautmann came to
the rescue and led them to success."
Trautmann's work at the research reactor was also seminal. Guenter F.
Herrmann, his thesis adviser at Mainz, rates Trautmann's development of rapid
chemical separation techniques and resonance ionization mass spectrometry (RIMS)
of actinide elements as major accomplishments. "Trautmann was the first to
master complicated separation schemes involving several steps on a time scale of
seconds," Herrmann says. "This made numerous new nuclides in the complex fission
product mixture accessible for study." Trautmann says these methods enabled
measurements of the fission properties of short-lived isotopes. Using a
centrifuge system developed with international partners, Trautmann then focused
on chemical properties of transactinide elements with atomic numbers of 104 or
greater.
RIMS was used by Trautmann and coworkers to determine the first ionization
potential of the elements americium through einsteinium for the first time and
for the ultratrace analysis of transuranium elements, particularly plutonium.
Trautmann has authored or coauthored more than 300 papers. He won the
Fritz-Strassmann Award of the German Chemical Society in 1984, the Helmholtz
Award of the Physikalisch-Technische Bundesanstalt Braunschweig in 1990, and the
Otto Hahn Award of the City of Frankfurt in 1998. The award address will be
presented before the Division of :Nuclear Chemistry & Technology at Fall 2007
ACS National Meeting in Boston.-ALEX
TULLO
from Chemical & Engineering News, February 6, 2006 -
Volume 84, Number 6
Glenn T. Seaborg Award for Nuclear Chemistry
Sponsored by the ACS Division of Nuclear Chemistry & Technology
Steven W. Yates, professor of chemistry, physics, and astronomy
and currently chair of the Department of Chemistry at the University of
Kentucky, has made contributions in all areas of his profession as a
researcher and an educator, as an editor and a writer, and as a member of
government and private-sector science panels. This award recognizes him for
his groundbreaking studies of multi-phonon excitations in atomic nuclei and
for the development of techniques for measuring very short nuclear
lifetimes.
Yates, 59, received a B.S. degree in chemistry from the University of
Missouri, Columbia, in 1968 and a Ph.D. in nuclear chemistry from Purdue
University in 1973, where he studied with Patrick Daly.
Following his dissertation work at Purdue, during which he characterized
a new class of negative-parity states in transitional nuclei and explained
them in terms of the semidecoupled model, he accepted a two-year
postdoctoral fellowship at Argonne National Laboratory. While there, he
investigated the properties of actinide nuclei, primarily by
light-ion-scattering and transfer reactions. These investigations led to
meaningful predictions, based on single-particle energies, of the ultimate
stability of superheavy elements. In 1975, Yates moved to the University of
Kentucky, where he initiated a program of nuclear structure studies. His
early work, with measurements performed at Oak Ridge National Laboratory,
included the first observation of the backbending phenomenon in the
y-vibrational band of a deformed nucleus. This discovery was key in
describing backbending in terms of rotational hand interactions and band
crossings.
In the late 1970s, Yates began the experiments for which he is best known
at the University of Kentucky's Van de Graaff accelerator. Although the
inelastic neutron-scattering reaction, first characterized by Glenn T.
Seaborg and his colleagues, had been used by others, Yates can be credited
with recognizing and developing the spectroscopic power of this reaction and
exploiting its potential.
Yates's studies of multiphonon excitations in spherical and deformed
nuclei are his most enduring contributions. The identification of both the K
= 0 and K = 4 two-phonon g-vibrational
excitations in a deformed nucleus is a remarkable achievement; however,
Yates's efforts to understand the octupole excitations are even more
significant. In nuclei near the 82-neutron shell closure, he found early
evidence for complete multiplets of quadrupole-octupole coupled states, and
his search for two-phonon octupole states led to the identification of the
0+ member of the long-sought two-phonon quartet in 208Pb.
This result provided a textbook example of collective excitations in
nuclei and must be regarded as confirming the existence of two-phonon
octupole vibrations. His group later provided candidates for two additional
members of this quartet. Because these identifications rely on knowledge of
electric dipole transition rates, his group then launched a study to
understand these transitions in spherical nuclei. This work led to the
characterization of perhaps thefinest example of weak coupling in nuclei.
Yates's most recent work has focused on determining how persistent
quadrupole vibrations are in nuclei. He and his colleagues have
characterized complete three-phonon multiplets in several nuclei, and, if
four-phonon multiplets still retain their collective character, his group
holds promise for identifying these excitations as well.
His contributions in other areas are also notable. In addition to
receiving both university and student initiated awards for his teaching, he
has been a regular contributor of educational articles in the Journal of
Chemical Education. He has been involved in ACS's Summer Schools in
Nuclear Chemistry since their inception. Ten doctoral and seven master's
students working under his direction have received degrees, and he has
mentored more than a dozen postdocs. The award address will be presented
before the Division of Nuclear Chemistry & Technology.—Linda Raber |
|
2005 Glenn T. Seaborg Nuclear
Chemistry Award
|
 |
Luciano G. Moretto
Department of Chemistry
University of California -Berkeley
|
from Chemical & Engineering News, January 17, 2005 -
Volume 83, Number 3
| Sponsored by the ACS Division of Nuclear Chemistry & Technology
Luciano G. Moretto started out his intellectual life both
inquisitive and adventurous. If his research and reputation as a professor
of chemistry at the University of California, Berkeley, and faculty senior
scientist at Lawrence Berkeley National Laboratory serve as a guide, he
never lost a step since his days as a precocious child.
One colleague calls him "perhaps the most distinguished active scientist
working in the area of complex nuclear reactions." Another colleague adds,
"His contributions to nuclear level densities, fission formalism, complex
fragment emission, deeply inelastic reactions between heavy nuclei,
multifragmentation reactions, and scaling theory," along with his "advanced
arguments for the nuclear liquid-gas phase transition, have made him one--if
not 'the'--world expert in statistical theory as applied to complex nuclear
reactions."
As a schoolboy, Moretto's tedious Greek and Latin grammar classes weren't
enough to keep his curiosity satisfied. He supplemented his studies with
physics and chemistry books from a small local library. He says his
experiments left him with the "yellow stains of nitric acid and the black
stains of silver nitrate." One night he synthesized nitroglycerin. Prompted
by the "sweet and burning" taste a book told him nitroglycerin should have,
he tasted the concoction. The strong vascular dilator left him with the
worst headache of his life.
Later on, Moretto says he earned the best score in all of Italy on that
country's notoriously challenging "esame di maturità classica," an exam
taken at the end of high school. That performance secured him a scholarship
to continue his studies. After receiving his Ph.D. in chemistry from the
University of Pavia, Moretto set to work studying the yields of fission
fragments.
He then received a fellowship to work at Lawrence Berkeley National
Laboratory on slow neutron, fast neutron, and electron-induced fission
yields. He stayed in Berkeley for three years before returning to Italy
temporarily to teach.
In 1971, Moretto returned to Berkeley permanently and focused on the
study of nuclear reactions. He spent the 1970s inducing fission with
high-energy particles to determine, he says, how the shell structure "slowly
fades away" with increasing energy. This work led to influential papers on
nuclear level densities with John R. Huizenga.
In the late 1970s and the 1980s, Moretto's group studied deep-inelastic
collisions between heavy nuclei. The group studied how energy and angular
momentum relax from translational to internal motion.
More recently, Moretto's group was able to interpret multifragmentation
in terms of a liquid-vapor phase diagram. "It turns out that nuclear matter
does behave very much like a van der Waals fluid," he says. He says this
work "closed the circle" on his career in chemistry because of his
familiarity with phase diagrams as a young university student working
endlessly in a lab. "All of a sudden, we took the world of nuclear physics
into a more mundane and human frame of understanding," he says.
Also closing the circle is Moretto's hobby: using those grammar lessons
to read classical Greek and Latin literature, which he enjoys every night.
The award will be presented before the Division of Nuclear Chemistry &
Technology.--ALEXANDER TULLO |
|
2004 Glenn T. Seaborg Nuclear
Chemistry Award
|
 |
Donald Fleming
Department of Chemistry
University of British Columbia
|
from Chemical & Engineering News, January 5, 2004 - Volume 82,
Number 1
| Sponsored by the ACS Division of
Nuclear Chemistry & Technology Donald G.
Fleming is a high-tech ghost hunter. As a nuclear chemist, he
studies minuscule particles that flicker into existence for only tiny
fractions of seconds. But that's long enough for him to co-opt them for
his groundbreaking probes of basic chemistry.
Fleming, a professor of nuclear and physical chemistry
at the University of British Columbia (UBC), Vancouver, is being
recognized for his pioneering uses of muons in the probing of complex
chemical problems.
Modern physics has discovered a bewildering menagerie
of exotic subatomic particles. Fleming's particle of choice, the muon,
is kin to the electron, but with 200 times the mass and a half-life of
only 2 microseconds. A positive muon, though, acts much like a light
proton in matter. When such a particle replaces a hydrogen nucleus,
muonium is formed; at one-ninth the mass, muonium is light enough to
probe chemical reactions with a sensitivity unmatched by more mundane
atoms.
"As such, the muonium atom is the light isotope of
hydrogen and provides for unique measurements of kinetic isotope effects
at the most sensitive end of the mass scale," Fleming says. "Our study
of the chemical reaction rates of the muonium atom impacts directly on
theoretical understanding of quantum mass effects in chemical
reactivity, and these data have provided truly stringent tests of
chemical reaction rate theories."
Most of Fleming's data come from UBC's TRIUMF
cyclotron, where physicists smash accelerated protons into nuclear
targets such as beryllium or carbon nuclei. One possible outcome of the
resulting nuclear minestrone is production of short-lived particles
called pions, which subsequently decay into the muons Fleming uses.
He then has to work fast; a positive muon quickly
decays into a positron and a pair of neutrinos. Fleming has used those
short windows of time to study muonium in matter, particularly in
low-pressure gases, simultaneously testing basic theories of chemical
reactivity and molecular interaction. The technique he uses--and helped
develop--is µSR, which can be thought of as a form of muon-based
spectroscopy.
"The acronym was coined years ago to suggest analogies
with magnetic resonance and stands for 'muon spin relaxation' or
'resonance' or 'rotation' or even 'research,'" Fleming explains. "It
derives from the fact that the muon is produced 100% spin-polarized as a
result of the nuclear weak interaction in pion decay." When a muon
decays, the positron is emitted preferentially along the muon spin,
"thus endowing muon decay with a sensitive indicator of the interaction
of the muon spin with its environment, whether as the nucleus of the
muonium atom or in some other environment."
In addition to his work in the gas phase, Fleming has
also used µSR to study the spin relaxation and hyperfine coupling
constants of stabilized polyatomic radicals, as well as the motional
dynamics of free radicals in zeolites, heterogenous catalysts with a
ubiquitous presence in the petrochemical industry.
Fleming, 65, received a bachelor's degree in 1961 and
a master's in physical organic chemistry in 1963 from the University of
British Columbia and a Ph.D. in nuclear chemistry from the University of
California, Berkeley, in 1967. Two postdoctoral fellowships followed:
the first at the Nuclear Structure Laboratory at the University of
Rochester, N.Y.; the other at Niels Bohr Institute for Nuclear Physics
at the University of Copenhagen. He returned to UBC in 1971, when TRIUMF
was not much more than a hole in the ground, and has been a full
professor of chemistry there since 1981.
The award address will be presented before the
Division of Nuclear Chemistry & Technology.--AALOK MEHTA |
|
from Chemical & Engineering News, January 27, 2003 - Volume 81,
Number 04
|
2003 GLENN T. SEABORG
AWARD FOR NUCLEAR CHEMISTRY |
|
Demetrios G. Sarantites |
 |
If there's one area of chemistry that requires heavy
instrumental artillery, it's nuclear chemistry. To probe an atom's guts,
scientists need accelerators to split or fuse nuclei and blast them into new
energy states. And a whole science of sophisticated detector systems arose from
the need to examine the complex trails of gamma rays spit out by rapidly
spinning and highly excited (hot) nuclei.
Over the past several decades, chemistry professor
Demetrios G. Sarantites, at Washington University, in St. Louis, has
invented some of the most important such detectors used by nuclear scientists.
And thanks to these instruments, not only has Sarantites himself been able to
gain major insights into nuclear structures and processes, but hosts of other
scientists have been able to make important discoveries as well.
Sarantites was born in 1933 in Athens, Greece. He received a
B.S. in chemical engineering and an M.S. in chemistry from the Technical
University of Athens in 1956. After a three-year service at the Greek Naval
Academy, he went to Massachusetts Institute of Technology, where he was awarded
a Ph.D. in nuclear and inorganic chemistry in 1963.
After postdoc positions at MIT and at Washington University,
in 1964, Sarantites became an assistant professor at Washington University,
where he has been ever since. Now a full professor, he has also held visiting
professorships at the Nobel Institute of Physics in Stockholm; Niels Bohr
Institute in Roskilde, Denmark; and Lawrence Berkeley National Laboratory (LBNL)
in Berkeley, Calif.
During the 1960s and '70s, Sarantites pioneered the use of
germanium detectors for probing the nuclear structure of medium-sized atoms. In
the early 1980s, he was responsible for the creation of the spin spectrometer, a
groundbreaking spherical detector array installed at the Holifield Heavy Ion
Research Facility at Oak Ridge National Laboratory. The spin spectrometer was
the first to examine in great detail the gamma ray decay of excited nuclei.
Sarantites soon developed a spherical detector designed to
measure the spectra of hydrogen and helium isotopes, known as the Dwarf
Ball/Wall. This detector, used in combination with the spin spectrometer, gave
scientists the ability to simultaneously monitor particles and gamma rays.
He also collaborated on the powerful, sophisticated
Gammasphere detector system, an international project system at LBNL. In the
1990s, Sarantites developed the Microball, another small spherical detector that
fit inside the Gammasphere. The two devices combined made for an extremely
powerful, selective system. And with it, Sarantites was able to confirm the
existence of the then-theorized "island of superdeformation" in rapidly spinning
nuclei of around mass 80 and to study them extensively. He was also instrumental
in the discovery and study of superdeformation in nuclei of mass 60, and very
recently in mass 40.
Sarantites' latest device is Hercules, a new detector system
used with the Gammasphere that can identify trans-lead and trans-actinide fusion
products--a task made very difficult by their quick decay into fission products.
Throughout his illustrious 40-year career, Sarantites has also
published over 250 papers and presented numerous lectures.
The award address will be presented before the Division of
Nuclear Chemistry & Technology.--ELIZABETH WILSON
from Chemical & Engineering News, January 27, 2003 - Volume 81,
Number 04
|
2000 Glenn T. Seaborg Nuclear
Chemistry Award
|
 |
Richard G. "Dick" Hahn
Brookhaven National Laboratory
|
ACS Award for Nuclear Chemistry Sponsored by Gordon
& Breach Publishing Group
On a summer day in 1945, 10-year-old RICHARD L. HAHN was riding the subway in
New York City while a nearby commuter read the New York Times. It was a day Hahn
will never forget. "I saw the front page of the paper, and the headline
announced the dropping of the first atomic bomb over Japan," Hahn recalls. "That
was the very moment I became interested in nuclear science, and I've been
interested ever since."
Most recently, Hahn's interests led to his involvement with construction of
the high-profile Sudbury Neutrino Observatory (SNO), near Sudbury, Ontario. The
observatory, located 6,800 feet underground, began operations last summer and is
designed to detect neutrino interactions as they occur in real time. Hahn played
a substantial role in designing the chemical aspects of the neutrino detector
which contains 1,000 tons of pure heavy water, D2O in a 12-meter-wide
transparent acrylic plastic vessel surrounded by 7,000 tons of purified light
water, which acts as shielding.
Hahn also played a major role in designing and operating the international
GALLEX Solar Neutrino Experiment, which operated a neutrino detector containing
30 tons of gallium in a 100-ton aqueous target at the Gran Sasso National
Laboratory in Assergi, Italy. According to Hahn, the experiment which ended in
1997, led scientists to a deeper understanding of how the sun produces energy,
as well as an understanding of the properties of neutrinos.
The results for GALLEX and the world's four other solar neutrino detectors
have provided strong hints that the neutrino has a significant new property:
nonzero mass. This potential for "new science" beyond current physics theories
has generated great interest about neutrinos in the scientific community.
Before becoming interested in neutrinos, Hahn had already established himself
as a prominent nuclear chemist. His areas of research have included the
mechanisms of nuclear reactions induced by accelerated charged particles from
protons to heavy ions up to uranium, charged-particle activation analysis,
nuclear spectroscopy, discovery and characterization of new nuclides, solution
chemistry of lanthanides and actinides, fission studies, and searches for super
heavy elements.
In total, Hahn has published more than 100 articles on these and other
subjects, as well as numerous articles in the World Book Encyclopedia aimed at
students in grades seven through 12.
A native of New York City, Hahn studied nuclear chemistry at Columbia
University where he received a Ph.D. degree in 1960. He left university life in
1960, taking a research associate position at Brookhaven National Laboratory,
Upton, N.Y. After leaving Brookhaven in 1962, Hahn joined the Oak Ridge National
Laboratory in Tennessee, where he worked until 1987, serving in many positions,
one of which was director of the Transuranium Research Laboratory from 1974 to
1984. In 1987, he returned to Brookhaven, where he continues his work today as a
senior chemist.
As a visiting scientist, Hahn has worked in France, Germany, Italy, and
Canada. He is an active member of several professional organizations and served
as chairman of the American Chemical Society's Division of Nuclear Chemistry &
Technology in 1980.
Among his other honors, Hahn was named a scholar in residence in 1983 by
Southwestern University, Georgetown, Texas, and received the Radiation Industry
Award of the American Nuclear Society in 1977 for his research on
charged-particle activation analysis.
Ronald Rogers: from Chemical & Engineering News, January
17, 2000
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