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  • richardmitnick 10:37 am on February 21, 2021 Permalink | Reply
    Tags: , , Einsteinium [Es] chemistry captured, LBNLheavy element chemistry program, Periodic Table, , To date researchers have created more than two dozen synthetic chemical elements that don’t exist naturally on Earth.   

    From Physics Today: “Einsteinium chemistry captured” 

    Physics Today bloc

    From Physics Today

    18 Feb 2021
    Johanna L. Miller

    The creation of a rare molecule offers a glimpse of how atoms behave at the Periodic Table’s outer reaches.

    To date, researchers have created more than two dozen synthetic chemical elements that don’t exist naturally on Earth. Neptunium (atomic number Z = 93) and plutonium (Z = 94), the first two artificial elements after naturally occurring uranium, are produced in nuclear reactors by the thousands of kilograms. But the accessibility of transuranic elements drops quickly with Z: Einsteinium (Z = 99) can be made only in microgram quantities in specialized laboratories, fermium (Z = 100) is produced by the picogram and has never been purified, and all elements after that are made just one atom at a time.

    There are ways to probe the atomic properties of elements produced atom by atom (see, for example, Physics Today, June 2015, page 14). But when it comes to the traditional way of investigating how atoms behave—mixing them with other substances in solution to form chemical compounds—Es is effectively the end of the periodic table.

    Now Rebecca Abergel (head of Lawrence Berkeley National Laboratory’s heavy element chemistry program) and her colleagues have performed the most complicated and informative Es chemistry experiment to date. They chose to react Einsteinium [Es] with a so-called octadentate ligand—a single organic molecule, held together by the backbone shown in blue, that wraps around a central metal atom and binds to it from all sides—to create the molecular structure shown in the figure. In their previous work, Abergel and colleagues used the same ligand to study transition metals, lanthanides, and lighter actinides. When they were fortunate enough to acquire a few hundred nanograms of Es from Oak Ridge National Laboratory, they used it on that as well.

    Credit: Adapted from K. P. Carter et al., Nature 590, 85 (2021)

    Among other useful properties, the ligand acts as an antenna: It absorbs light in the UV and efficiently channels the energy to the central metal atom, which emits light at a range of longer wavelengths. That luminescence spectrum, which can be measured with just a tiny quantity of material, carries information about the central atom’s electronic energy levels.

    Between the luminescence spectroscopy and complementary x-ray absorption measurements, the researchers discovered that Es differs significantly in its behavior from both its upstairs neighbor holmium and the lighter actinides. The difference is almost certainly due to relativistic effects. The more highly charged an atomic nucleus, the faster the electrons whiz around it. When the electron speed is a significant fraction of the speed of light, it affects the atom’s quantum states in a way that’s extraordinarily difficult to model.

    All actinides exhibit relativistic effects, but the heavier ones especially so. Although Es is so scarce that its chemistry is unlikely to be of any technological importance, it could provide a benchmark for better theoretical understanding of the more abundant lighter actinides’ chemical behavior. Abergel and colleagues are especially interested in how those radioactive elements behave inside the human body—with an eye toward both harnessing their radiation as a cancer treatment and designing new drugs to treat radiation poisoning. (K. P. Carter et al., Nature 590, 85, 2021 [above]).

    See the full article here .


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    “Our mission

    The mission of Physics Today is to be a unifying influence for the diverse areas of physics and the physics-related sciences.

    It does that in three ways:

    • by providing authoritative, engaging coverage of physical science research and its applications without regard to disciplinary boundaries;
    • by providing authoritative, engaging coverage of the often complex interactions of the physical sciences with each other and with other spheres of human endeavor; and
    • by providing a forum for the exchange of ideas within the scientific community.”

  • richardmitnick 8:49 pm on February 16, 2021 Permalink | Reply
    Tags: "Experimental tests of relativistic chemistry will update the periodic table", , All chemistry students are taught about the periodic table, , , Having the ability to study the chemistry of superheavy elements could uncover new applications for these elements., However there are deviations from expected periodic trends., Osaka University [大阪大学; Ōsaka daigaku], Periodic Table, Relativistic chemistry, Rutherfordium, Superheavy elements are generally produced one at a time in nuclear fission reactions and deteriorate quickly.   

    From Osaka University [大阪大学; Ōsaka daigaku] via phys.org: “Experimental tests of relativistic chemistry will update the periodic table” 

    From Osaka University [大阪大学; Ōsaka daigaku]

    February 16, 2021

    Fig.1 Brief overview of the present study. Credit: Osaka University [大阪大学; Ōsaka daigaku].

    All chemistry students are taught about the periodic table, an organization of the elements that helps you identify and predict trends in their properties.

    For example, science fiction writers sometimes describe life based on the element silicon because it is in the same column in the periodic table as carbon.

    However, there are deviations from expected periodic trends. For example, lead and tin are in the same column in the periodic table and thus should have similar properties. However, whilst lead-acid batteries are common in cars, tin-acid batteries don’t work. Nowadays we know that this is because most of the energy in lead-acid batteries is attributable to relativistic chemistry but such chemistry was unknown to the researchers who originally proposed the periodic table.

    Relativistic chemistry is difficult to study in the superheavy elements, because such elements are generally produced one at a time in nuclear fission reactions and deteriorate quickly. Nevertheless, having the ability to study the chemistry of superheavy elements could uncover new applications for superheavy elements and for common lighter elements, such as lead and gold.

    In a recent study in Nature Chemistry, researchers from Osaka University studied how single atoms of superheavy rutherfordium metal react with two classes of common bases. Such experiments will help researchers use relativistic principles to better utilize the chemistry of many elements.

    Fig.2 Schematic diagram of online co-precipitation experiment of 261Rf. Credit: Osaka University [大阪大学; Ōsaka daigaku].

    “We prepared single atoms of rutherfordium at RIKEN [理研] accelerator research facility, and attempted to react these atoms with either hydroxide bases or amine bases,” explains Yoshitaka Kasamatsu, lead author on the study. “Radioactivity measurements indicated the end result.”

    Researchers can better understand relativistic chemistry from such experiments. For example, rutherfordium forms precipitate compounds with hydroxide base at all concentrations of base, yet its homologues zirconium and hafnium in high concentrations. This difference in reactivity may be attributable to relativistic chemistry.

    “If we had a way to produce a pure rutherfordium precipitate in larger quantities, we could move forward with proposing practical applications,” says senior author Atsushi Shinohara. “In the meantime, our studies will help researchers systematically explore the chemistry of superheavy elements.”

    Relativistic chemistry explains why bulk gold metal is not silver-colored, as one would expect based on periodic table predictions. Such chemistry also explains why mercury metal is a liquid at room temperature, despite periodic table predictions. There may be many unforeseen applications that arise from learning about the chemistry of superheavy elements. These discoveries will depend on newly reported protocols and ongoing fundamental studies such as this one by Osaka University [大阪大学; Ōsaka daigaku] researchers.

    See the full article here.


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  • richardmitnick 12:52 pm on February 8, 2021 Permalink | Reply
    Tags: "The Stars Within Us", , , , , , , Creation of heavier elements requires more extreme environments usually triggered by the end of a star’s life in a supernova., , How the Elements Inside You and Everything Were Forged., Intense heat and pressure fused hydrogen atoms to form helium and lithium., , , Periodic Table, Within a few hundred million years after the Big Bang clouds of hydrogen gas condensed into the first stars., Within the first three minutes following the Big Bang the fundamental building blocks of matter formed and merged into the first element–hydrogen.   

    From National Science Foundation (US): “The Stars Within Us” 

    From National Science Foundation (US)

    Credit: Nicolle R. Fuller/NSF.

    Humans have always looked to the stars and studied them. Over the past century, science has revealed the fundamental role stars play for nearly everything in existence, including the elements on the Periodic Table.

    Periodic Table from
    International Union of Pure and Applied Chemistry 2019.

    The birth, life and death of every star creates and disseminates the elements of the Periodic Table throughout the universe, a cycle that began nearly 14 billion years ago and repeats continuously today.

    Without it, the Earth and everything on it – air, water, soil, plants, wildlife, and human life – would not exist.

    The Stars Within Us: How the Elements Inside You, and Everything, Were Forged.

    Within the first three minutes following the Big Bang, the fundamental building blocks of matter formed and merged into the first element–hydrogen. Within a few hundred million years after the Big Bang, clouds of hydrogen gas condensed into the first stars. In the cores of those stars, intense heat and pressure fused hydrogen atoms to form helium and lithium.

    Recently, astronomers from several U.S.-based universities detected a signal from the birth of those early stars. Since the stars are too distant to be seen with telescopes, the astronomers searched for indirect evidence, such as a tell-tale change in the background electromagnetic radiation that permeates the universe, called the cosmic microwave background [CMB].

    CMB per ESA/Planck.

    Supported for more than a decade by the U.S. National Science Foundation, researchers placed a radio antenna not much larger than a refrigerator in the Australian desert and found clear evidence of these massive blue stars.

    EDGES telescope in a radio quiet zone at the Murchison Radio-astronomy Observatory in Western Australia.

    More chaos, more elements

    The normal functions of a star—those that make it shine brightly and burn at temperatures of thousands of degrees—create the simplest and lightest elements. Creation of heavier elements requires more extreme environments, usually triggered by the end of a star’s life in a supernova.

    After the hydrogen in a star’s core is exhausted, the star fuses helium to form progressively heavier elements, such as carbon and iron. As this fuel runs out, the star either explodes into a supernova, seeding the universe with those elements, or violently collapses, creating neutron stars and black holes. In such violent implosions, star collisions, and the extreme environments around black holes, the heavier elements are forged and then spread far across interstellar space.

    Artist’s now iconic illustration of two merging neutron stars. The beams represent the gamma-ray burst while the rippling space-time grid indicates the isotropic gravitational waves. Credit: A. Simonnet/National Science Foundation/LIGO/Sonoma State University.

    In 2017, for the first time in history, researchers using the twin detectors of NSF’s Laser Interferometer Gravitational-Wave Observatory detected gravitational waves created by the collision of two neutron stars.

    Localizations of gravitational-wave signals detected by LIGO in 2015 (GW150914, LVT151012, GW151226, GW170104), more recently, by the LIGO-Virgo network (GW170814, GW170817). After Virgo (IT) came online in August 2018.

    The researchers worked with the Europe-based Virgo gravitational wave detector and some 70 ground- and space-based telescopes across the globe to track and record the gamma radiation, X-rays, light, and radio waves that cascaded from the explosion.

    MIT /Caltech Advanced aLigo at Hanford, WA (US), Livingston, LA, (US) and VIRGO Gravitational Wave interferometer, near Pisa, Italy.

    The observations revealed signatures of recently synthesized elements, including gold and platinum, solving a decades-long mystery of how nearly half of all elements heavier than iron are produced.

    Some of the heaviest elements, such as uranium, are forged near black holes and in the powerful jets that can emanate from them, such as those that surge away from “feeding” black holes, like blazars, an active galactic nucleus with a relativistic jet composed of ionized matter.

    The timeline of the universe, with the first stars emerging by 180 million years after the Big Bang and black holes another 70 millions years after. Photo Credit: N.R.Fuller/National Science Foundation.

    The NSF-supported Event Horizon Telescope presented the first direct visual evidence of a supermassive black hole in 2019, and NSF’s Ice Cube detector has worked with collaborating observatories to trace a cosmic neutrino to its blazar source.

    EHT map.

    Messier 87*, The first image of the event horizon of a black hole. This is the supermassive black hole at the center of the galaxy Messier 87. Image via JPL/ Event Horizon Telescope Collaboration released on 10 April 2019.

    These extreme environments in space are where the heaviest elements are formed, but because they have such short half-lives, scientists have yet to directly witness their formation, and they have not survived to be found on Earth today.

    This is where researchers in the laboratory have built upon what we have learned from studying the cosmos.

    Filling the Periodic Table

    On Earth, ancient cultures were first to isolate a handful of elements, such as copper and mercury, though in recent centuries, scientists have identified and isolated more than 100 more. They are categorized using the Periodic Table—first published in 1869 by Russian chemist Dmitri Mendeleev. The initial Periodic Table contained 28 elements, and Mendeleev predicted the existence of unidentified elements, leaving gaps for future scientists to fill.

    Laboratory experiments have expanded the Periodic Table to include 118 known elements. For some, particularly the heaviest, they were only discovered when physicists crafted them from the fusion of lighter elements. The heaviest known element is oganesson, which holds 118 protons in its nucleus, although only for fractions of a millisecond.

    Like the stars that constantly recycle and distribute elements throughout space, researchers in all disciplines continue their efforts to expand the Periodic Table and deepen the understanding of the atoms from which we are constructed. This is an ongoing process, and future generations of scientists are just now making their initial observations or conducting their first experiments that will expand the knowledge about the universe and ourselves.

    See the full article here .


    Please help promote STEM in your local schools.

    Stem Education Coalition
    The National Science Foundation (NSF) (US) is an independent federal agency created by Congress in 1950 “to promote the progress of science; to advance the national health, prosperity, and welfare; to secure the national defense…we are the funding source for approximately 24 percent of all federally supported basic research conducted by America’s colleges and universities. In many fields such as mathematics, computer science and the social sciences, NSF is the major source of federal backing.

    We fulfill our mission chiefly by issuing limited-term grants — currently about 12,000 new awards per year, with an average duration of three years — to fund specific research proposals that have been judged the most promising by a rigorous and objective merit-review system. Most of these awards go to individuals or small groups of investigators. Others provide funding for research centers, instruments and facilities that allow scientists, engineers and students to work at the outermost frontiers of knowledge.

    NSF’s goals — discovery, learning, research infrastructure and stewardship — provide an integrated strategy to advance the frontiers of knowledge, cultivate a world-class, broadly inclusive science and engineering workforce and expand the scientific literacy of all citizens, build the nation’s research capability through investments in advanced instrumentation and facilities, and support excellence in science and engineering research and education through a capable and responsive organization. We like to say that NSF is “where discoveries begin.”

    Many of the discoveries and technological advances have been truly revolutionary. In the past few decades, NSF-funded researchers have won some 236 Nobel Prizes as well as other honors too numerous to list. These pioneers have included the scientists or teams that discovered many of the fundamental particles of matter, analyzed the cosmic microwaves left over from the earliest epoch of the universe, developed carbon-14 dating of ancient artifacts, decoded the genetics of viruses, and created an entirely new state of matter called a Bose-Einstein condensate.

    NSF also funds equipment that is needed by scientists and engineers but is often too expensive for any one group or researcher to afford. Examples of such major research equipment include giant optical and radio telescopes, Antarctic research sites, high-end computer facilities and ultra-high-speed connections, ships for ocean research, sensitive detectors of very subtle physical phenomena and gravitational wave observatories.

    Another essential element in NSF’s mission is support for science and engineering education, from pre-K through graduate school and beyond. The research we fund is thoroughly integrated with education to help ensure that there will always be plenty of skilled people available to work in new and emerging scientific, engineering and technological fields, and plenty of capable teachers to educate the next generation.

    No single factor is more important to the intellectual and economic progress of society, and to the enhanced well-being of its citizens, than the continuous acquisition of new knowledge. NSF is proud to be a major part of that process.

    Specifically, the Foundation’s organic legislation authorizes us to engage in the following activities:

    Initiate and support, through grants and contracts, scientific and engineering research and programs to strengthen scientific and engineering research potential, and education programs at all levels, and appraise the impact of research upon industrial development and the general welfare.
    Award graduate fellowships in the sciences and in engineering.
    Foster the interchange of scientific information among scientists and engineers in the United States and foreign countries.
    Foster and support the development and use of computers and other scientific methods and technologies, primarily for research and education in the sciences.
    Evaluate the status and needs of the various sciences and engineering and take into consideration the results of this evaluation in correlating our research and educational programs with other federal and non-federal programs.
    Provide a central clearinghouse for the collection, interpretation and analysis of data on scientific and technical resources in the United States, and provide a source of information for policy formulation by other federal agencies.
    Determine the total amount of federal money received by universities and appropriate organizations for the conduct of scientific and engineering research, including both basic and applied, and construction of facilities where such research is conducted, but excluding development, and report annually thereon to the President and the Congress.
    Initiate and support specific scientific and engineering activities in connection with matters relating to international cooperation, national security and the effects of scientific and technological applications upon society.
    Initiate and support scientific and engineering research, including applied research, at academic and other nonprofit institutions and, at the direction of the President, support applied research at other organizations.
    Recommend and encourage the pursuit of national policies for the promotion of basic research and education in the sciences and engineering. Strengthen research and education innovation in the sciences and engineering, including independent research by individuals, throughout the United States.
    Support activities designed to increase the participation of women and minorities and others underrepresented in science and technology.

    At present, NSF has a total workforce of about 2,100 at its Alexandria, VA, headquarters, including approximately 1,400 career employees, 200 scientists from research institutions on temporary duty, 450 contract workers and the staff of the NSB office and the Office of the Inspector General.

    NSF is divided into the following seven directorates that support science and engineering research and education: Biological Sciences, Computer and Information Science and Engineering, Engineering, Geosciences, Mathematical and Physical Sciences, Social, Behavioral and Economic Sciences, and Education and Human Resources. Each is headed by an assistant director and each is further subdivided into divisions like materials research, ocean sciences and behavioral and cognitive sciences.

    Within NSF’s Office of the Director, the Office of Integrative Activities also supports research and researchers. Other sections of NSF are devoted to financial management, award processing and monitoring, legal affairs, outreach and other functions. The Office of the Inspector General examines the foundation’s work and reports to the NSB and Congress.

    Each year, NSF supports an average of about 200,000 scientists, engineers, educators and students at universities, laboratories and field sites all over the United States and throughout the world, from Alaska to Alabama to Africa to Antarctica. You could say that NSF support goes “to the ends of the earth” to learn more about the planet and its inhabitants, and to produce fundamental discoveries that further the progress of research and lead to products and services that boost the economy and improve general health and well-being.

    As described in our strategic plan, NSF is the only federal agency whose mission includes support for all fields of fundamental science and engineering, except for medical sciences. NSF is tasked with keeping the United States at the leading edge of discovery in a wide range of scientific areas, from astronomy to geology to zoology. So, in addition to funding research in the traditional academic areas, the agency also supports “high risk, high pay off” ideas, novel collaborations and numerous projects that may seem like science fiction today, but which the public will take for granted tomorrow. And in every case, we ensure that research is fully integrated with education so that today’s revolutionary work will also be training tomorrow’s top scientists and engineers.

    Unlike many other federal agencies, NSF does not hire researchers or directly operate our own laboratories or similar facilities. Instead, we support scientists, engineers and educators directly through their own home institutions (typically universities and colleges). Similarly, we fund facilities and equipment such as telescopes, through cooperative agreements with research consortia that have competed successfully for limited-term management contracts.

    NSF’s job is to determine where the frontiers are, identify the leading U.S. pioneers in these fields and provide money and equipment to help them continue. The results can be transformative. For example, years before most people had heard of “nanotechnology,” NSF was supporting scientists and engineers who were learning how to detect, record and manipulate activity at the scale of individual atoms — the nanoscale. Today, scientists are adept at moving atoms around to create devices and materials with properties that are often more useful than those found in nature.

    Dozens of companies are gearing up to produce nanoscale products. NSF is funding the research projects, state-of-the-art facilities and educational opportunities that will teach new skills to the science and engineering students who will make up the nanotechnology workforce of tomorrow.

    At the same time, we are looking for the next frontier.

    NSF’s task of identifying and funding work at the frontiers of science and engineering is not a “top-down” process. NSF operates from the “bottom up,” keeping close track of research around the United States and the world, maintaining constant contact with the research community to identify ever-moving horizons of inquiry, monitoring which areas are most likely to result in spectacular progress and choosing the most promising people to conduct the research.

    NSF funds research and education in most fields of science and engineering. We do this through grants and cooperative agreements to more than 2,000 colleges, universities, K-12 school systems, businesses, informal science organizations and other research organizations throughout the U.S. The Foundation considers proposals submitted by organizations on behalf of individuals or groups for support in most fields of research. Interdisciplinary proposals also are eligible for consideration. Awardees are chosen from those who send us proposals asking for a specific amount of support for a specific project.

    Proposals may be submitted in response to the various funding opportunities that are announced on the NSF website. These funding opportunities fall into three categories — program descriptions, program announcements and program solicitations — and are the mechanisms NSF uses to generate funding requests. At any time, scientists and engineers are also welcome to send in unsolicited proposals for research and education projects, in any existing or emerging field. The Proposal and Award Policies and Procedures Guide (PAPPG) provides guidance on proposal preparation and submission and award management. At present, NSF receives more than 42,000 proposals per year.

    To ensure that proposals are evaluated in a fair, competitive, transparent and in-depth manner, we use a rigorous system of merit review. Nearly every proposal is evaluated by a minimum of three independent reviewers consisting of scientists, engineers and educators who do not work at NSF or for the institution that employs the proposing researchers. NSF selects the reviewers from among the national pool of experts in each field and their evaluations are confidential. On average, approximately 40,000 experts, knowledgeable about the current state of their field, give their time to serve as reviewers each year.

    The reviewer’s job is to decide which projects are of the very highest caliber. NSF’s merit review process, considered by some to be the “gold standard” of scientific review, ensures that many voices are heard and that only the best projects make it to the funding stage. An enormous amount of research, deliberation, thought and discussion goes into award decisions.

    The NSF program officer reviews the proposal and analyzes the input received from the external reviewers. After scientific, technical and programmatic review and consideration of appropriate factors, the program officer makes an “award” or “decline” recommendation to the division director. Final programmatic approval for a proposal is generally completed at NSF’s division level. A principal investigator (PI) whose proposal for NSF support has been declined will receive information and an explanation of the reason(s) for declination, along with copies of the reviews considered in making the decision. If that explanation does not satisfy the PI, he/she may request additional information from the cognizant NSF program officer or division director.

    If the program officer makes an award recommendation and the division director concurs, the recommendation is submitted to NSF’s Division of Grants and Agreements (DGA) for award processing. A DGA officer reviews the recommendation from the program division/office for business, financial and policy implications, and the processing and issuance of a grant or cooperative agreement. DGA generally makes awards to academic institutions within 30 days after the program division/office makes its recommendation.

  • richardmitnick 11:24 am on October 25, 2019 Permalink | Reply
    Tags: "The final piece in the puzzle of the origin of the elements", , , , , , , , , Periodic Table   

    From Niels Bohr Institute: “The final piece in the puzzle of the origin of the elements” 

    University of Copenhagen

    Niels Bohr Institute bloc

    From Niels Bohr Institute

    23 October 2019

    Darach Watson
    Cosmic Dawn Center (DAWN)
    Niels Bohr Institute
    University of Copenhagen
    Mobile: +45 24 80 38 25
    Email: darach@nbi.ku.dk

    Maria Hornbek
    SCIENCE Communication
    University of Copenhagen
    Mobile: +45 22 95 42 83
    Email: maho@science.ku.dk

    The first unequivocal evidence of where the heaviest elements were forged has now been found by a research group led by the University of Copenhagen. For the first time, an element heavier than iron has been clearly detected in the collision of two neutron stars, resolving one of the fundamental questions about the history of the universe.

    Artist’s impression of merging neutron stars. Credit: University of Warwick/Mark Garlick

    Since the 1950s, we have known that hydrogen and helium were formed during the Big Bang, and that heavier elements up to iron are created by nuclear fusion in stars and when stars explode as supernovae. But iron is only no. 26 out of about 90 naturally occurring elements in the periodic table. Where the other elements heavier than iron came from has long been a mystery. For some time now we have known that some of them form in the envelopes of low-mass stars, so-called AGB stars. But only half of the elements heavier than iron are created this way. So where do the rest come from?

    Now a research team led by astrophysicist Darach Watson of the Niels Bohr Institute has, for the first time, found spectroscopic evidence that heavy elements are created in the explosion that happens when two neutron stars collide. The researchers have identified the metal strontium in a spectrum from a neutron star collision observed in 2017. The result is published in the scientific journal Nature.

    “Before this we were unable to identify any specific element created in a neutron star merger. There were strong indications and good circumstantial evidence that heavy elements were created in these events, but the unequivocal evidence was missing until now,” says astrophysicist Darach Watson of the Niels Bohr Institute at the University of Copenhagen, adding:

    “One of the most fundamental questions about the universe has been: where do the elements of the periodic table come from? You could say that this is the last piece of the puzzle of the formation of the elements.”

    Grundstoffet strontium as synthetic crystals. Credit: Heinrich Pniok

    Unique stellar crash in 2017 helped the researchers.

    The only way to create substances heavier than iron is by a process called neutron capture, where neutrons penetrate an atomic nucleus – for example, an iron atom – which absorbs the neutrons, creating a new, heavier atomic nucleus and thus a new element. Neutron capture can be either fast or slow, in the so-called r-process (rapid) or s-process (slow). About half of the substances created by neutron capture are primarily formed by the r-process. Elements formed almost exclusively by the r-process are typically very heavy and near the end of the periodic table: gold, platinum, uranium.

    It is this rapid process whose location has never been established. In recent years, the scientific consensus has evolved toward the idea that much of the r-process happens when two neutron stars collide – but the definitive evidence has thus far been missing. The neutron star collision triggers a phenomenon called a kilonova, where a fraction of the neutron stars’ combined mass is released and spread into the universe in a giant explosion.

    The only time the phenomenon was well-observed was in August 2017, when two neutron stars collided in a galaxy approx. 140 million light years from Earth; a collision first discovered through its gravitational wave signature and then followed-up by observatories such as the European Southern Observatory (ESO) in the Atacama desert in Chile.

    ESO VLT at Cerro Paranal in the Atacama Desert, •ANTU (UT1; The Sun ),
    •KUEYEN (UT2; The Moon ),
    •MELIPAL (UT3; The Southern Cross ), and
    •YEPUN (UT4; Venus – as evening star).
    elevation 2,635 m (8,645 ft) from above Credit J.L. Dauvergne & G. Hüdepohl atacama photo,

    The spectra gathered back then at ESO are what Darach Watson and his colleagues have been analyzing ever since. However, no one at the time was able to identify any specific elements. Using a so-called black body spectrum, Darach Watson and colleagues succeeded in reproducing the early spectra of that kilonova, in which the element strontium is prominent. Curiously, strontium is one of the lighter of the heavy elements, and this in itself is important:

    “It was thought that perhaps only the heaviest elements, such as uranium and gold, formed in neutron star mergers. Now we know that the lighter of the heavy elements are also created in these mergers. And so it tells us that neutron star collisions produce a broad range of the heavy elements, from the lightest to the very heaviest,” says astrophysicist and co-author Jonatan Selsing, who until recently was a postdoc at the Niels Bohr Institute.

    The researchers’ next step is to try to identify more elements in the spectra of the kilonova. If successful, they expect to find elements heavier than strontium – possibly barium and lanthanum.

    The research article is written by:

    Darach Watson (Niels Bohr Institute & Cosmic Dawn Center, University of Copenhagen, Denmark),
    Camilla J. Hansen (Max Planck Institute for Astronomy, Heidelberg, Germany),
    Jonatan Selsing (Niels Bohr Institute & Cosmic Dawn Center, University of Copenhagen, Denmark),
    Andreas Koch (Center for Astronomy of Heidelberg University, Germany),
    Daniele B. Malesani (DTU Space, National Space Institute, Technical University of Denmark, & Niels Bohr Institute & Cosmic Dawn Center, University of Copenhagen, Denmark),
    Anja C. Andersen (Niels Bohr Institute, University of Copenhagen, Denmark),
    Johan P. U. Fynbo (Niels Bohr Institute & Cosmic Dawn Center, University of Copenhagen, Denmark),
    Almudena Arcones (Institute of Nuclear Physics, Technical University of Darmstadt, Germany & GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt, Germany),
    Andreas Bauswein (GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt, Germany & Heidelberg Institute for Theoretical Studies, Germany),
    Stefano Covino (Astronomical Observatory of Brera, Italy’s National Institute for Astrophysics, Milan, Italy),
    Aniello Grado (Capodimonte Astronomical Observatory, Italy’s National Institute for Astrophysics, Naples, Italy),
    Kasper E. Heintz (Centre for Astrophysics and Cosmology, Science Institute, University of Iceland, Reykjavík, Iceland & Cosmic Dawn Center, Niels Bohr Institute University of Copenhagen, Denmark),
    Leslie Hunt (Arcetri Astrophysical Observatory, Italy’s National Institute for Astrophysics, Florence, Italy),
    Chryssa Kouveliotou (Physics Department, The George Washington University, Washington DC, USA & Astronomy, Physics and Statistics Institute of Sciences Washington DC, USA),
    Giorgos Leloudas (DTU Space, National Space Institute, Technical University of Denmark, & Niels Bohr Institute, University of Copenhagen, Denmark),
    Andrew Levan (Radboud University, Nijmegen, the Netherlands & Department of Physics, University of Warwick, UK),
    Paolo Mazzali (Astrophysics Research Institute, Liverpool John Moores University, UK & Max Planck Institute for Astrophysics, Garching, Germany),
    Elena Pian (Astrophysics and Space Science Observatory of Bologna, Italy’s National Institute for Astrophysics, Bologna, Italy).

    See the full article here .


    Stem Education Coalition

    Niels Bohr Institute Campus

    Niels Bohr Institute (Danish: Niels Bohr Institutet) is a research institute of the University of Copenhagen. The research of the institute spans astronomy, geophysics, nanotechnology, particle physics, quantum mechanics and biophysics.

    The Institute was founded in 1921, as the Institute for Theoretical Physics of the University of Copenhagen, by the Danish theoretical physicist Niels Bohr, who had been on the staff of the University of Copenhagen since 1914, and who had been lobbying for its creation since his appointment as professor in 1916. On the 80th anniversary of Niels Bohr’s birth – October 7, 1965 – the Institute officially became The Niels Bohr Institute.[1] Much of its original funding came from the charitable foundation of the Carlsberg brewery, and later from the Rockefeller Foundation.[2]

    During the 1920s, and 1930s, the Institute was the center of the developing disciplines of atomic physics and quantum physics. Physicists from across Europe (and sometimes further abroad) often visited the Institute to confer with Bohr on new theories and discoveries. The Copenhagen interpretation of quantum mechanics is named after work done at the Institute during this time.

    On January 1, 1993 the institute was fused with the Astronomic Observatory, the Ørsted Laboratory and the Geophysical Institute. The new resulting institute retained the name Niels Bohr Institute.

    The University of Copenhagen (UCPH) (Danish: Københavns Universitet) is the oldest university and research institution in Denmark. Founded in 1479 as a studium generale, it is the second oldest institution for higher education in Scandinavia after Uppsala University (1477). The university has 23,473 undergraduate students, 17,398 postgraduate students, 2,968 doctoral students and over 9,000 employees. The university has four campuses located in and around Copenhagen, with the headquarters located in central Copenhagen. Most courses are taught in Danish; however, many courses are also offered in English and a few in German. The university has several thousands of foreign students, about half of whom come from Nordic countries.

    The university is a member of the International Alliance of Research Universities (IARU), along with University of Cambridge, Yale University, The Australian National University, and UC Berkeley, amongst others. The 2016 Academic Ranking of World Universities ranks the University of Copenhagen as the best university in Scandinavia and 30th in the world, the 2016-2017 Times Higher Education World University Rankings as 120th in the world, and the 2016-2017 QS World University Rankings as 68th in the world. The university has had 9 alumni become Nobel laureates and has produced one Turing Award recipient

  • richardmitnick 8:53 am on July 2, 2019 Permalink | Reply
    Tags: A team of scientists from Lawrence Livermore National Laboratory (LLNL) and Russia that discovered five elements from 1989 to 2010., “Astrophysicists also are interested in these types of reactions because of NIF’s ability to duplicate the conditions at the interior of stars” Shaughnessy said., , , , Periodic Table, , Synthetic elements- flerovium (atomic number 114) moscovium (115) livermorium (116) tennessine (117) and oganesson (118)   

    From Lawrence Livermore National Laboratory: Women in STEM- “Stellar reactions in a galaxy not so far, far away” Dawn Shaughnessy 

    From Lawrence Livermore National Laboratory

    July 1, 2019
    Anne M Stark

    Dawn Shaughnessy examines a sample plate used to collect the nuclear reaction products produced when neutrons from fusion during a NIF shot bombard research materials. Photo by Jason Laurea/LLNL

    Few people over the course of history have had a hand in discovering an atomic element. Yet nuclear chemist Dawn Shaughnessy joined a team of scientists from Lawrence Livermore National Laboratory (LLNL) and Russia that discovered five elements from 1989 to 2010.

    Now she leads the Nuclear and Radiochemistry Group of the Physics and Life Sciences Directorate at LLNL and uses the National Ignition Facility (NIF) to generate some of the most extreme conditions in our solar system for high energy density experiments.


    Russian scientist Alexander Yeremin (left), Dawn Shaughnessy, and former LLNL scientist John Wild stand in front of a particle separator from the U400 cyclotron at Russia’s Flerov Laboratory of Nuclear Reactions in 2003. The experiments by these researchers and their colleagues were used to investigate the nuclear properties of elements copernicium (atomic number 112) and flerovium (114). Courtesy of Dawn Shaughnessy

    “NIF is the brightest neutron source in the world, and we use it to produce nuclear reactions that are relevant to stockpile stewardship and nuclear forensics programs. The reactions cannot be done by using accelerators or other means,” said Shaughnessy, who also is serving a one-year appointment as scientific editor of the Laboratory’s Science & Technology Review.

    National Ignition Facility at LLNL

    Her first experience with NIF came before it was even operational. She joined a working group to determine whether nuclear science could be performed at NIF, and, if so, what types of diagnostics would be needed for making the measurements.

    “I was fascinated,” she said. “It was really cutting-edge stuff. You could make measurements in a plasma. No one else in the world was able to do that.”

    She began investigating how to make experimental platforms for studying the nuclear reactions of materials of interest, such as the elements nickel, yttrium and zirconium (see “Providing Data for Nuclear Detectives”). But only over the last couple of years did her team develop a technique capable of doping target capsules with these elements.

    Serving as the NIF target is a 2-millimeter-diameter capsule lined on the inner surface with extremely small amounts of the material (about 1016 atoms) and filled with deuterium and tritium (DT) gas. The neutrons produced by the DT fusion during the shot bombard the material and cause nuclear reactions to occur. The fusion energy blows the products of the reaction outward, and the resulting solid debris is collected by specialized diagnostic instruments so that important radiochemical characteristics, such as rates of reactions, can be evaluated back inside a laboratory.

    “Astrophysicists also are interested in these types of reactions because of NIF’s ability to duplicate the conditions at the interior of stars,” Shaughnessy said.

    By studying nuclear reactions within the star-like plasma generated by NIF, researchers can better explore nuclear synthesis, the stellar process that eventually creates heavier elements by fusing together lighter elements and particles. Sometimes this process, which is a progression of different nuclear reactions, must first create lighter elements before heavier ones can be created.

    One such nuclear reaction under investigation occurs inside a class of stars that have masses on the order of the sun. It has boron absorbing a proton to form beryllium and an alpha particle. This nuclear reaction illustrates the type of interactions between atoms and particles that interest nuclear chemists.

    As is true for so many of the projects at LLNL, the search for basic science understanding can yield big returns for other programs. Through the Discovery Science program, about 8 percent of NIF’s shots each year are dedicated to these types of experiments.

    “Everything we’ve done for Discovery Science ties exactly into the platforms that we are developing for the Stockpile Stewardship Program,” Shaughnessy said. “It has helped teach us how to dope capsules with materials, how to collect materials coming out of a shot and how to conduct various analyses.”

    But it is not just in the stellar cauldrons of stars in other galaxies where atomic concoctions are brewed. It happens right here in our solar system, without even having to escape Earth’s gravitational force. And from early on, this attracted Shaughnessy.

    “Einsteinium is my favorite element,” she said. “It doesn’t get enough credit because its chemistry is relatively ordinary. But I think it is really cool.”

    Her affinity toward einsteinium wells from her Ph.D. research at the University of California, Berkeley, into the fission of this synthetic, radioactive element. But after graduation, she turned in the opposite direction at Lawrence Berkeley National Laboratory by studying environmental factors of plutonium, which she feels is one of the most interesting elements because it has many oxidation states and forms, and neptunium, plutonium’s next-door neighbor on the periodic table.

    This radioactive background is what led Shaughnessy to join LLNL’s Stockpile Radiochemistry Group in 2002, which is the same year she began hunting for elements that had never been observed before. The five elements that the team discovered were forged in a particle accelerator at Flerov Laboratory of Nuclear Reactions in Russia.

    “The heavy element program at the Lab was very small,” said Shaughnessy, who became the team’s principal investigator in 2005. “It was a team effort by people who were really dedicated to the science. Most of us had a background in it from somewhere else.”

    They filled out the bottom row of the periodic table by co-discovering the heavy elements flerovium (atomic number 114), moscovium (115), livermorium (116), tennessine (117) and oganesson (118) (see “Collaboration Expands the Periodic Table, One Element at a Time”).

    If any of these short-lived, synthetic elements have familiar sounding names, like livermorium, it might be because many elements that appear in the latter part of the periodic table are given names to honor people and places connected to important achievements in science.

    Periodic table Sept 2017. Wikipedia

    Shaughnessy recalls that the name davincium was tossed around during this period of discovery, and she hopes it will be used one day in commemoration of the early days of scientific investigation.

    It is hard not to envision Leonardo da Vinci, sketching his latest invention on a table while his Italian robe flowed around him. Shaughnessy, however, looked in a much more futuristic direction for her wardrobe inspiration: she owns a custom-made Jedi robe from a Jedi robe shop in England.

    “I am an enormous fan of ‘Star Wars,’” she said — no surprise to anyone who has worked with her. “I’ve been a fan since it first came out in 1977, when I saw it in a theater and connected with it at a young age. ‘Star Wars’ has always been a part of me. I still have my Star Wars figures. And now that we have new Star Wars movies again, I can get to share it with my daughter. I’ve probably seen the movies hundreds of times by this point.”

    Even at NIF, the force is strong with Shaughnessy. The influence runs deep. When trying to name a newly developed solid debris collecting diagnostic — which happens to look spaceship-like — she came up with Vast Area Detector for Experimental Radiochemistry, or VADER. She quickly points out, though, that she is of course aligned with the light side of the force — or, as in this case, the “laser light side.”

    Shaughnessy’s passion for this epic science fiction saga has helped propel her to transcend real-world boundaries, where science is fact and breakthroughs bring distant worlds much closer to home.

    —Dan Linehan

    See the full article here .


    Please help promote STEM in your local schools.

    Stem Education Coalition

    LLNL Campus

    Operated by Lawrence Livermore National Security, LLC, for the Department of Energy’s National Nuclear Security Administration
    Lawrence Livermore National Laboratory (LLNL) is an American federal research facility in Livermore, California, United States, founded by the University of California, Berkeley in 1952. A Federally Funded Research and Development Center (FFRDC), it is primarily funded by the U.S. Department of Energy (DOE) and managed and operated by Lawrence Livermore National Security, LLC (LLNS), a partnership of the University of California, Bechtel, BWX Technologies, AECOM, and Battelle Memorial Institute in affiliation with the Texas A&M University System. In 2012, the laboratory had the synthetic chemical element livermorium named after it.
    LLNL is self-described as “a premier research and development institution for science and technology applied to national security.” Its principal responsibility is ensuring the safety, security and reliability of the nation’s nuclear weapons through the application of advanced science, engineering and technology. The Laboratory also applies its special expertise and multidisciplinary capabilities to preventing the proliferation and use of weapons of mass destruction, bolstering homeland security and solving other nationally important problems, including energy and environmental security, basic science and economic competitiveness.

    The Laboratory is located on a one-square-mile (2.6 km2) site at the eastern edge of Livermore. It also operates a 7,000 acres (28 km2) remote experimental test site, called Site 300, situated about 15 miles (24 km) southeast of the main lab site. LLNL has an annual budget of about $1.5 billion and a staff of roughly 5,800 employees.

    LLNL was established in 1952 as the University of California Radiation Laboratory at Livermore, an offshoot of the existing UC Radiation Laboratory at Berkeley. It was intended to spur innovation and provide competition to the nuclear weapon design laboratory at Los Alamos in New Mexico, home of the Manhattan Project that developed the first atomic weapons. Edward Teller and Ernest Lawrence,[2] director of the Radiation Laboratory at Berkeley, are regarded as the co-founders of the Livermore facility.

    The new laboratory was sited at a former naval air station of World War II. It was already home to several UC Radiation Laboratory projects that were too large for its location in the Berkeley Hills above the UC campus, including one of the first experiments in the magnetic approach to confined thermonuclear reactions (i.e. fusion). About half an hour southeast of Berkeley, the Livermore site provided much greater security for classified projects than an urban university campus.

    Lawrence tapped 32-year-old Herbert York, a former graduate student of his, to run Livermore. Under York, the Lab had four main programs: Project Sherwood (the magnetic-fusion program), Project Whitney (the weapons-design program), diagnostic weapon experiments (both for the Los Alamos and Livermore laboratories), and a basic physics program. York and the new lab embraced the Lawrence “big science” approach, tackling challenging projects with physicists, chemists, engineers, and computational scientists working together in multidisciplinary teams. Lawrence died in August 1958 and shortly after, the university’s board of regents named both laboratories for him, as the Lawrence Radiation Laboratory.

    Historically, the Berkeley and Livermore laboratories have had very close relationships on research projects, business operations, and staff. The Livermore Lab was established initially as a branch of the Berkeley laboratory. The Livermore lab was not officially severed administratively from the Berkeley lab until 1971. To this day, in official planning documents and records, Lawrence Berkeley National Laboratory is designated as Site 100, Lawrence Livermore National Lab as Site 200, and LLNL’s remote test location as Site 300.[3]

    The laboratory was renamed Lawrence Livermore Laboratory (LLL) in 1971. On October 1, 2007 LLNS assumed management of LLNL from the University of California, which had exclusively managed and operated the Laboratory since its inception 55 years before. The laboratory was honored in 2012 by having the synthetic chemical element livermorium named after it. The LLNS takeover of the laboratory has been controversial. In May 2013, an Alameda County jury awarded over $2.7 million to five former laboratory employees who were among 430 employees LLNS laid off during 2008.[4] The jury found that LLNS breached a contractual obligation to terminate the employees only for “reasonable cause.”[5] The five plaintiffs also have pending age discrimination claims against LLNS, which will be heard by a different jury in a separate trial.[6] There are 125 co-plaintiffs awaiting trial on similar claims against LLNS.[7] The May 2008 layoff was the first layoff at the laboratory in nearly 40 years.[6]

    On March 14, 2011, the City of Livermore officially expanded the city’s boundaries to annex LLNL and move it within the city limits. The unanimous vote by the Livermore city council expanded Livermore’s southeastern boundaries to cover 15 land parcels covering 1,057 acres (4.28 km2) that comprise the LLNL site. The site was formerly an unincorporated area of Alameda County. The LLNL campus continues to be owned by the federal government.


    DOE Seal

  • richardmitnick 1:23 am on March 5, 2019 Permalink | Reply
    Tags: Deuterium and tritium- called heavy hydrogen have been used to make hydrogen bombs, Fusion Technology-when burned in a controlled way hydrogen offers the cleanest fuel producing only water as the waste product, , Periodic Table, Protons also are the key component of fuel cells. Rather than burn the hydrogen fuel cells convert it to electricity and are seen as the way of the future. They do this by splitting the hydrogen gas i, , With rapid advances in chemistry and engineering hydrogen stations could start to appear soon becoming as commonplace as gasoline filling stations are today.   

    From The Conversation: “Lightweight of periodic table plays big role in life on Earth” 

    From The Conversation

    Nicholas Leadbeater

    Periodic table Sept 2017. Wikipedia

    Although hydrogen is the lightweight of the chemical elements, it packs a real punch when it comes to its role in life and its potential as a solution to some of the world’s challenges. As we celebrate the 150th anniversary of the periodic table, it seems reasonable to tip our hat to this, the first element on the table.

    One oxygen atom is connected to two hydrogen atoms to make water. Liaskovskaia Ekaterina/SHutterstock.com

    Hydrogen is the most abundant element in the universe, but not on Earth due to its light weight, which allows the gas to just float off into space. Hydrogen is essential to our life – it fuels the sun, which converts hundreds of million tons of hydrogen into helium every second. And two hydrogen atoms are attached to one oxygen atom to make water. Both these things make our planet habitable.

    Not only does hydrogen enable the sun to warm the Earth and help create the water that sustains life, but this simplest of all the elements may also provide the key to finding a clean fuel source to power the planet.

    Hydrogen’s yin and yang as an energy source

    Like many other chemical elements, although hydrogen is of immense value to us, it also has a darker side. Being lighter than air, it makes things float, which is why is was used in early airships. But hydrogen is highly explosive, and in 1937 the German airship the Hindenburg exploded on its attempt to dock with its mooring mast after a transatlantic journey, killing 36 people.

    Isotopes of hydrogen: protium, deuterium and tritium. Designua/Shutterstock.com

    Hydrogen’s cousins, deuterium and tritium, called heavy hydrogen, have been used to make hydrogen bombs. Here, the heavy hydrogen atoms merge together in a process called nuclear fusion to make helium, a bit like the reaction that takes place in the sun. The amount of energy produced by this process is greater than any other known process – the area at the center of the explosion is essentially vaporized, generating shock waves that destroy anything in their way. The bright white light produced can blind people many miles away. It also produces radioactive products that are carried in the air and cause widespread contamination of the environment.

    Taming the beast, however, could be the solution to the energy problems of the future. When burned in a controlled way, hydrogen offers the cleanest fuel, producing only water as the waste product. That’s refreshing when compared with a gasoline engine that produces climate change-inducing carbon dioxide and a range of other nasty gases. When stored under high pressure and very low temperature of -400 degrees Fahrenheit, hydrogen exists as a liquid, and its combustion with oxygen is used for propelling rockets into space.

    However, a car with a tank of highly explosive hydrogen rocket fuel doesn’t sound like a safe bet. There’s currently lots of research focused on solving the storage problem. Large numbers of scientists are trying to develop chemical compounds that safely hold and release hydrogen. This is actually a hard nut to crack and is something that will take time and many great minds to solve.

    The power of hydrogen

    Hydrogen atoms also give things like lemon juice and vinegar their distinctive tart taste. Positively charged hydrogen atoms, called protons, having been stripped of their only electron, float around in these solutions and are the key component of acids. The chemistry of these protons is also responsible for driving photosynthesis, the process whereby plants turn light energy into chemical energy, and powering many processes in the human body.

    This is the symbol and electron diagram for hydrogen. BlueRingMedia/Shutterstock.com

    Protons also are the key component of fuel cells. Rather than burn the hydrogen, fuel cells convert it to electricity and are seen as the way of the future. They do this by splitting the hydrogen gas into protons and electrons on one side of the fuel cell. The positively charged protons move over to the other side of the cell, leaving behind the negatively charged electrons. This creates a flow of electricity between the sides of the cell when connected with an external circuit. This current can power an electric motor placed in this circuit. Hydrogen-powered trains are already in operation in Germany, and several international car manufacturers are developing fuel-cell powered cars. Again, the only byproduct of the process is water.

    In the future, I think we will see increasing use of hydrogen as a fuel. For it to be useful, there are two major challenges. A big one is the storage issue. Engineers need to figure out how to store hydrogen safely and start to build places where people can fill up. With rapid advances in chemistry and engineering, hydrogen stations could start to appear soon, becoming as commonplace as gasoline filling stations are today. This sort of infrastructure is going to be essential. You don’t want run out of fuel on a journey because, unlike a gas-powered car, you can’t call a friend to bring you a canister of hydrogen.

    Hydrogen fuel pump at Shell station, for automobiles running on pollution-free hydrogen-powered fuel cells. Rob Crandall/Shutterstock.com

    See the full article here .


    Please help promote STEM in your local schools.

    Stem Education Coalition

    The Conversation launched as a pilot project in October 2014. It is an independent source of news and views from the academic and research community, delivered direct to the public.
    Our team of professional editors work with university and research institute experts to unlock their knowledge for use by the wider public.
    Access to independent, high quality, authenticated, explanatory journalism underpins a functioning democracy. Our aim is to promote better understanding of current affairs and complex issues. And hopefully allow for a better quality of public discourse and conversation.

  • richardmitnick 9:18 am on February 28, 2019 Permalink | Reply
    Tags: An element is defined by the number of protons it contains, At the far edge of the periodic table elements decay within instants of their formation offering very little time to study their properties, , , Each element comes in a variety of types known as isotopes distinguished by the number of neutrons in the nucleus, For superheavy atoms chemistry gets weird, Periodic Table, , Scientists are hoping to stretch the periodic table even further beyond tennessine and three other recently discovered elements (113 115 and 118) that completed the table’s seventh row.   

    From Science News: “Extreme elements push the boundaries of the periodic table” 

    From Science News

    February 27, 2019
    Emily Conover

    For superheavy atoms, chemistry gets weird.

    SMASH HIT To create new elements and study the chemistry of the periodic table’s heaviest atoms, researchers at the GSI Helmholtz Center for Heavy Ion Research in Darmstadt, Germany, use the apparatus above to create beams of ions that scientists then smash into other elements.

    GSI Helmholtz Centre for Heavy Ion Research GmbH, Darmstadt, Germany,

    The rare radioactive substance made its way from the United States to Russia on a commercial flight in June 2009. Customs officers balked at accepting the package, which was ensconced in lead shielding and emblazoned with bold-faced warnings and the ominous trefoil symbols for ionizing radiation. Back it went across the Atlantic.

    U.S. scientists enclosed additional paper work and the parcel took a second trip, only to be rebuffed again. All the while, the precious cargo, 22 milligrams of an element called berkelium created in a nuclear reactor at Oak Ridge National Laboratory in Tennessee, was deteriorating. Day by day, its atoms were decaying. “We were all a little frantic on our end,” says Oak Ridge nuclear engineer Julie Ezold.

    On the third try, the shipment cleared customs. At a laboratory in Dubna, north of Moscow, scientists battered the berkelium with calcium ions to try to create an even rarer substance. After 150 days of pummeling, the researchers spotted six atoms of an element that had never been seen on Earth. In 2015, after other experiments confirmed the discovery, element 117, tennessine, earned a spot on the periodic table (SN: 2/6/16, p. 7).

    Scientists made radioactive berkelium at the High Flux Isotope Reactor at Oak Ridge National Laboratory in Tennessee (shown), and shipped it to Russia to be bombarded with a beam of calcium-48 to yield the superheavy element tennessine. ORNL/Flickr (CC BY 2.0)

    ORNL High Flux Isotope Reactor

    Scientists are hoping to stretch the periodic table even further, beyond tennessine and three other recently discovered elements (113, 115 and 118) that completed the table’s seventh row. Producing the next elements will require finessing new techniques using ultrapowerful beams of ions, electrically charged atoms. Not to mention the stress of shipping more radioactive material across borders.

    But questions circulating around the periodic table’s limits are too tantalizing not to make the effort. It’s been 150 years since Russian chemist Dmitrii Mendeleev created his periodic table. Yet “we still cannot answer the question: Which is the heaviest element that can exist?” says nuclear chemist Christoph Düllmann of the GSI Helmholtz Center for Heavy Ion Research in Darmstadt, Germany.

    At the far edge of the periodic table, elements decay within instants of their formation, offering very little time to study their properties. In fact, scientists still know little about the latest crew of newfound elements. So while some scientists are hunting for never-before-seen elements, others want to learn more about the table’s newcomers and the strange behaviors those superheavy elements may exhibit.

    For such outsized atoms, chemistry can get weird, as atomic nuclei, the hearts at the center of each atom, bulge with hundreds of protons and neutrons. Around them swirl great flocks of electrons, some moving at close to the speed of light. Such extreme conditions might have big consequences — messing with the periodic table’s tidy order, in which elements in each column are close chemical kin that behave in similar ways.

    In Russia, scientist Vladislav Shchegolev inspects a package of berkelium after its overseas flight in 2009. The material was later used to create element 117, tennessine.
    Courtesy of ORNL.

    Scientists keep pushing these superheavy elements further as part of the search for what’s poetically known as the island of stability. Atoms with certain numbers of protons and neutrons are expected to live longer than their fleeting friends, persisting perhaps for hours rather than fractions of a second. Such an island would give scientists enough time to study those elements more closely and understand their quirks. The first glimpses of that mysterious atoll have been spotted, but it’s not clear how to get a firm footing on its shores.

    Driving all this effort is a deep curiosity about how elements act at the boundaries of the periodic table. “This might sound corny, but it’s really just [about] pure scientific understanding,” says nuclear chemist Dawn Shaughnessy of Lawrence Livermore National Laboratory in California. “We have these things that are really at the extremes of matter and we don’t understand right now how they behave.”

    Assembling atoms

    An element is defined by the number of protons it contains. Create an atom with more protons than ever before, and you’ve got yourself a brand new element. Each element comes in a variety of types, known as isotopes, distinguished by the number of neutrons in the nucleus. Changing the number of neutrons in an atom’s nucleus alters the delicate balance of forces that makes a nucleus stable or that causes it to decay quickly. Different isotopes of an element might have wildly different half-lives, the period of time it takes for half of the atoms in a sample to decay into smaller elements.

    Mendeleev’s periodic table, presented to the Russian Chemical Society on March 6, 1869, contained only 63 elements (SN: 1/19/19, p. 14). At first, scientists added to the periodic table by isolating elements from naturally occurring materials, for example, by scrutinizing minerals and separating them into their constituent parts. But that could take scientists only so far. All the elements beyond uranium (element 92) must be created artificially; they do not exist in significant quantities in nature. Scientists discovered elements beyond uranium by bombarding atoms with neutrons or small atomic nuclei or by sifting through the debris from thermonuclear weapons tests.

    But to make the heaviest elements, researchers adopted a new brute force approach: slamming beams of heavy atoms into a target, a disk that holds atoms of another element. If scientists are lucky, the atoms in the beam and target fuse, creating a new atom with a bigger, bulkier nucleus, perhaps one holding more protons than any other known.

    Researchers are using this strategy to go after elements 119 and 120. Scientists want to create such never-before-seen atoms to test how far the periodic table goes, to satisfy curiosity about the forces that hold atoms together and to understand what bizarre chemistry might occur with these extreme atoms.


    How the periodic table went from a sketch to an enduring masterpiece
    150 years ago, Mendeleev perceived the relationships of the chemical elements
    REVOLUTIONARY Russian chemist Dmitrii Mendeleev (shown around 1880) was the first to publish a periodic table, which put the known elements into a logical order and left room for elements not yet discovered. Heritage Image Partnership Ltd/Alamy Stock Photo.

    An ordered vision

    Mendeleev’s periodic table, published in 1869, was a vertical chart that organized 63 known elements by atomic weight. This arrangement placed elements with similar properties into horizontal rows. The title, translated from Russian, reads: “Draft of system of elements: based on their atomic masses and chemical characteristics.”

    The periodic table’s lineup

    The search is gearing up for the next superheavy elements, 119 and 120 (red boxes in the table below). Meanwhile, scientists are studying the known superheavy elements (blue) to better understand how such large atoms behave.


    Coaxing nuclei to combine into a new element is done only at highly specialized facilities in a few locations across the globe, including labs in Russia and Japan. Researchers carefully choose the makeup of the beam and the target in hopes of producing a designer atom of the element desired. That’s how the four newest elements were created: nihonium (element 113), moscovium (115), tennessine (117) and oganesson (118) (SN Online: 11/30/16).

    To create tennessine, for example, scientists combined beams of calcium with a target made of berkelium — once the berkelium finally made it through customs in Russia. The union makes sense when you consider the number of protons in each nucleus. Calcium has 20 protons and berkelium has 97, making for 117 protons total, the number found in tennessine’s nucleus. Combine calcium with the next element down the table, californium, and you get element 118, oganesson.

    Using calcium beams — specifically a stable calcium isotope with a combined total of 48 protons and neutrons known as calcium-48 — has been highly successful. But to create bigger nuclei would take increasingly exotic materials. The californium and berkelium used in previous efforts are so rare that the target materials had to be made at Oak Ridge, where researchers stew materials in a nuclear reactor for months and carefully process the highly radioactive product that comes out. All that work might produce just milligrams of the material.

    To discover element 119 using a calcium-48 beam, researchers would need a target made of einsteinium (element 99) which is even rarer than californium and berkelium. “We can’t make enough einsteinium,” says Oak Ridge physicist James Roberto. Scientists need a new approach. They’ve switched to relatively untested techniques relying on different beams of particles.

    Decay parade

    To discover oganesson-294 (with 294 protons and neutrons), scientists slammed calcium ions into a californium target and observed the chain of radioactive decays initiated by the new element.



    But any new approach would have to produce new elements often enough to be worthwhile. It took almost nine years for a Japanese experiment to prove the existence of nihonium. In that time, researchers spotted the element only three times.

    To avoid such long waits, scientists are carefully choosing their tactics and revving up improved machines to quicken the search.

    A team at the RIKEN Nishina Center for Accelerator-Based Science near Tokyo uses beams of vanadium (element 23), rather than calcium, slamming them into curium (element 96) in the quest to grab elemental glory and find element 119. The group is starting with an existing accelerator and will soon switch to an accelerator upgraded to pump out ion beams that pack more punch. That revamped accelerator could be ready within a year, says RIKEN nuclear chemist Hiromitsu Haba.

    Meanwhile, a new laboratory at the Joint Institute for Nuclear Research, or JINR, in Dubna called the Superheavy Element Factory boasts an accelerator that will crank out ion beams that pummel the target at 10 times the rate of its predecessor. In an upcoming experiment, scientists plan to crash beams of titanium (element 22) into berkelium and californium targets to attempt to produce elements 119 and 120.

    Once JINR’s new experiment is up and running, 119 might be discovered after a couple of years, says JINR nuclear physicist Yuri Oganessian, for whom oganesson, one of several elements discovered there, was named.

    Scientists in Russia have built a new accelerator facility, the Superheavy Element Factory, to search for elements 119 and 120. JINR.

    Relativity rules

    Simply detecting an element, however, doesn’t mean scientists know much about it. “How would one kilogram of flerovium behave, if I had it?” Düllmann asks, referring to element 114. “It would be unlike any other material.”

    The known superheavy elements — those beyond number 103 on the table — are too short-lived to create a chunk big enough to hold in the palm of your hand. So scientists are limited to studying individual atoms, getting to know each new element by analyzing its properties, including how easily it reacts with other substances.

    One big question is whether the periodicity the table is named for applies to superheavy elements. In the table, elements are ordered according to their number of protons, arranged so that the elements in each column have similar properties. Lithium, sodium and others in the first column react violently with water, for example. Elements in the last column, known as noble gases, are famously inert (SN: 1/19/19, p. 18). But for the newest, heaviest elements at the periodic table’s outer reaches, that long-standing rule of chemistry may unravel; some superheavy elements may behave differently from neighbors sitting above them in the table.

    For nuclei crammed with 100-plus protons, a special type of physics takes center stage. Electrons zip around these giant nuclei, sometimes surpassing 80 percent the speed of light. According to Einstein’s special theory of relativity, when particles move that fast, they seem to gain mass. That property changes how closely the electrons hug the nucleus, and as a result, how easily the atoms share electrons to produce chemical reactions. In such atoms, “relativity rules, and standard common wisdom breaks down,” says nuclear physicist Witold Nazarewicz of Michigan State University in East Lansing. “We have to write new textbooks on those atoms.”

    Getting heavy

    The nucleus of superheavy oganesson has 118 protons and many neutrons (blue and red). Its 118 electrons (green) surround the nucleus. Carbon, which is much lighter, contains just six protons and six electrons (not to scale).

    T. Tibbitts

    Some of the periodic table’s more familiar elements are already affected by special relativity. The theory explains why gold has a yellowish hue and why mercury is liquid at room temperature (SN: 2/18/17, p. 11). “Without relativity, a car would not start,” says theoretical chemist Pekka Pyykkö of the University of Helsinki. The reactions that power a car battery depend on special relativity.

    Relativity’s influence may surge as scientists progress along the periodic table. In 2018 in Physical Review Letters, Nazarewicz and colleagues reported that oganesson could be utterly bizarre (SN Online: 2/12/18). The table’s heaviest element, oganesson sits among the reclusive noble gases that shun reactions with other elements. But oganesson bucks the trend, theoretical calculations suggest, and may instead be reactive.

    Oganesson’s chemistry is a hot topic, but scientists haven’t yet been able to directly probe its properties with experiments because oganesson is too rare and fleeting. “All the theoreticians are now running around this element trying to make spectacular predictions,” says theoretical chemist Valeria Pershina of GSI. Similarly, some calculations suggest that flerovium might lean in the opposite direction, being relatively inert, even though it inhabits the same column as more reactive elements such as lead.

    Chemists are striving to test such calculations about how superheavy elements behave. But there is nothing traditional about these chemistry experiments. There are no scientists in white coats wielding flasks and Bunsen burners. “Because we make these things one atom at a time, we can’t do what most people think of as chemistry,” Lawrence Livermore’s Shaughnessy says.

    The experiments can run for months with only a few atoms to show for it. Scientists put those atoms in contact with other elements to see if the two react. At GSI, Düllmann and colleagues are looking at whether flerovium sticks to gold surfaces. Likewise, Shaughnessy and colleagues are testing whether flerovium will glom on to ring-shaped molecules, chosen so that the heavy element could fit inside the molecule’s ring. These studies will test how easily flerovium bonds with other elements, revealing whether it behaves as expected based on its place on the periodic table.

    It’s not just chemical reactions that can get wacky for superheavy elements. Atomic nuclei can be warped into various shapes when packed with protons. Oganesson may have a “bubble” in its nucleus, with fewer protons in its center than at its edges (SN: 11/26/16, p. 11). Still more extreme nuclei may be doughnut-shaped, Nazarewicz says.

    Even the most basic properties of these elements, such as their mass, need to be measured. While scientists had estimated the mass of the various isotopes of the latest new elements using indirect measurements, the arguments supporting those mass estimates weren’t airtight, says Jacklyn Gates of Lawrence Berkeley National Laboratory in California. “They hinge on physics not throwing you a curveball.”

    Jacklyn Gates and Ken Gregorich of the FIONA experiment at Lawrence Berkeley National Laboratory made the first measurements of the masses of recently discovered elements 113 and 115.
    Marilyn Chung/Berkeley Lab

    So Gates and colleagues directly measured the masses of isotopes of nihonium and moscovium using an accelerator at Lawrence Berkeley. An apparatus called FIONA helped researchers measure the masses, thanks to electromagnetic fields that steered an ion of each element onto a detector. The location where each ion hit indicated how massive it was.

    The nihonium isotope the researchers detected had a mass number of 284, meaning its nucleus had a combined total of 284 protons and neutrons. Moscovium had a mass number of 288. Those masses were as predicted, the scientists reported in November in Physical Review Letters. It took about a month just to find one atom of each element.
    Island views

    If researchers could coax these fleeting elements to live longer, studying their properties might be easier. Scientists have caught enticing visions of increasing life spans lying just out of reach — the fabled island of stability (SN: 6/5/10, p. 26). Scientists hope that the isotopes on that island, which would be packed with lots of neutrons, may live long enough that their chemistry can be studied in detail.

    When the idea of an island of stability was proposed in the 1960s, scientists had suggested that the isotopes on its shores might live millions of years. Advances in theoretical physics have since knocked that time frame down, Nazarewicz says. Instead, nuclear physicists now expect the island’s inhabitants to stick around for minutes, hours or maybe even a day — a pleasant eternity for superheavy elements.

    To reach the island of stability, scientists must create new isotopes of known elements. Researchers already know which direction they need to row: They must cram more neutrons into the nuclei of the superheavy elements that have already been discovered. Currently, scientists can’t make atoms with enough neutrons to reach the island’s center, where isotopes are expected to be most stable. But the signs of this island’s existence are already clear. The half-lives of superheavy elements tend to shoot up as scientists pack more neutrons into each nucleus, approaching the island. Flerovium’s half-life increases by almost a factor of 700 as five more neutrons are added, from three milliseconds to two seconds.

    Long life

    Each row below is an element, and each column a different isotope. Atoms are expected to be more stable on the island of stability (predicted location shown). As isotopes of elements (gray squares) approach the island, they tend to live longer, as more neutrons fill the nucleus. Flerovium’s half-life, for example, increases from 0.003 to two seconds.

    T. Tibbitts

    Sources: S. Hofmann et al/Pure and Applied Chemistry 2018; W. Nazarewicz; Y. Oganessian

    Reaching this island “is our big dream,” Haba says. “Unfortunately, we don’t have a very good method to reach the island.” That island is thought to be centered around isotopes that bulge with around 184 neutrons and something like 110 protons. Making such neutron-rich nuclei would demand new, difficult techniques, such as using beams of radioactive particles instead of stable ones. Although radioactive beams can be produced at RIKEN, Haba says, the beams aren’t intense enough to produce new elements at a reasonable rate.

    Still, superheavy element sleuths are keeping at it to learn how these weird atoms behave.

    End of the line

    To fully grasp nature’s extremes, scientists want to know where the periodic table ends.

    “Everybody knows at some point there will be an end,” Düllmann says. “There will be a heaviest element, ultimately.” The table will be finished when we’ve discovered all elements with isotopes that live at least a hundredth of a trillionth of a second. That’s the limit for what qualifies as an element, according to the standards set by the International Union of Pure and Applied Chemistry. More ephemeral nuclei wouldn’t have enough time to gather a crew of electrons. Since the give-and-take of electrons is the basis of chemical reactions, lone nuclei wouldn’t exhibit chemistry at all, and therefore don’t deserve a spot on the table.

    “Where it will exactly end is difficult to say,” Nazarewicz says. Calculations of how quickly a nucleus will decay by fission, or splitting in two, are uncertain, which makes it hard to estimate how long elements might live without actually creating them.

    The linear accelerator at RIKEN in Japan, used to discover element 113*, is being refurbished to probe for element 119. RIKEN

    *According to a statement via email from LLNL, 113, was first found at LLNL; but on 113, Riken published first and so got the credit.

    And the final table may contain holes or other odd features. That could happen if, within a row of elements, there’s one spot for which no isotope persists long enough to qualify as an element.

    Another idiosyncrasy: Elements may not be arranged in sequential order by the number of protons they contain, according to calculations in a 2011 paper by Pyykkö in Physical Chemistry Chemical Physics. Element 139, for example, might sit to the right of element 164 — if such heavy elements indeed exist. That’s because special relativity alters the normal order in which electrons slot themselves into shells, arrangements that define how the electrons swirl about the atom. That pattern of shell filling is what gives the periodic table its shape, and the unusual filling may mean scientists decide to assign elements to spots out of order.

    But additions to the table could dry up before that happens if scientists reach the limit of their ability to create heavier elements. When elements live minuscule fractions of a second, even the atom’s trip to a detector may take too long; the element would decay before it ever had a chance to be spotted.

    In reality, there’s no clear idea of how to search for elements beyond 119 and 120. But the picture has seemed bleak before.

    “We should not underestimate the next generation. They may have smart ideas. They will have new technologies,” Düllmann says. “The next element is always the hardest. But it’s probably not the last one.”

    See the full article here .


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  • richardmitnick 8:39 am on October 24, 2017 Permalink | Reply
    Tags: , , , Periodic Table   

    From Manu Garcia: “Our atoms” 

    Manu Garcia, a friend from IAC.

    The universe around us.
    Astronomy, everything you wanted to know about our local universe and never dared to ask.

    Manu Astrologus

    Where do our atoms?
    The hydrogen that is in your body, present in every molecule of water came from the Big Bang. No other significant sources of hydrogen in the universe. The carbon body formed by nuclear fusion within the stars, like oxygen. Much of the iron body formed during supernovae stars, stellar explosions that occurred long ago and far away. Gold in their jewelery was probably made of neutron stars during collisions that may have been visible as gamma-ray bursts short or events of gravitational waves. Elements such as phosphorus and copper are present in our bodies in small amounts but are essential for the functioning of all known life. It presented the periodic table is color-coded to indicate the best estimate of humanity in terms of nuclear origin of all known elements. Nuclear sites creating some elements, such as copper, are not well known and remain topics of observational and computational research.

    Image Credit & License: Wikipedia : Cmglee ; Data: Jennifer Johnson (OSU) .

    Posted in Astronomy Picture of the Day, APOD on 24 October 2017

    The periodic table.
    Modern periodic table with 18 columns.

    Of Tximitx – Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=52698867

    The periodic table is an arrangement of the chemical elements in a table, ordered by their atomic number (number of protons), its electron configuration and chemical properties. This arrangement shows periodic trends, as elements with similar behavior in the same column.

    In the words of Theodor Benfey, table and periodic law “are the heart of chemistry, comparable to the theory of evolution in biology (which happened to the concept of the Great Chain of Being), and the laws of thermodynamics in classical physics. ”

    The rows of the table are called periods and columns groups. Some groups have names. For example group 17 is the halogens and the group 18 of the noble gases. The table also is divided into four blocks with some similar chemical properties. Because the positions are ordered, the table can be used to obtain relationships between the properties of the elements, or predict properties of new elements yet discovered or synthesized. The periodic table provides a useful tool for analyzing the chemical behavior and is widely used in chemistry and other science framework.

    Dmitri Mendeléyev in 1869 published the first version of the periodic table was widely recognized. The developed to illustrate periodic trends in the properties of the then known elements, to sort the items based on its chemical properties, although Julius Lothar Meyer, working separately conducted an order from the physical properties of atoms . Mendeleev also predicted some properties of then unknown elements anticipated that occupy the empty places in your table. Subsequently it showed that most of his predictions were correct when the items in question were discovered.

    Mendeleev periodic table has since been expanded and enhanced with the discovery or synthesis of new elements and development of new theoretical models to explain the chemical behavior. The current structure was designed by Alfred Werner from the version of Mendeleev. There are also other newspapers arrangements according to different properties and use it as you want to give (didactics, geology, etc.).

    Have been discovered or synthesized all elements of atomic number 1 (hydrogen) to 118 (oganesón); IUPAC confirmed the elements 113, 115, 117 and 118 on December 30, 2015, and their names and official symbols were made public on November 28, 2016. The first 94 exist naturally, although some only found in small amounts and were synthesized in the laboratory before being found in nature. the elements with atomic numbers 95 to 118 only they have been synthesized in laboratories. There were also produced numerous synthetic radioisotopes of elements present in nature. Elements of 95-100 existed in nature in the past but is currently not. The research to find new elements for synthesis of higher atomic numbers continues.

    See the full article here .

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  • richardmitnick 9:13 am on October 28, 2015 Permalink | Reply
    Tags: , Isotopes, , Nuclides, Periodic Table   

    From LLNL: “Lab scientists discover five new nuclei” 

    Lawrence Livermore National Laboratory

    Oct. 27, 2015

    Anne M Stark

    Lawrence Livermore National Laboratory scientists were part of an international team that discovered five new nuclei: U 218, Np 219, Bk 233, Am 223 and Am 229.

    Lawrence Livermore scientists, in conjunction with international researchers, have discovered five new atomic nuclei to be added the chart of nuclides.

    The study, conducted this fall, focuses on developing new methods of synthesis for super heavy elements. The newly discovered, exotic nuclei are one isotope each of heavy elements berkelium, neptunium and uranium and two isotopes of the element americium.

    Other participants include scientists from Manipal University, India; GSI-Giessen, Germany; Justus Liebig University Giessen, Germany; Japan Atomic Energy Agency; and the joint Institute for Nuclear Research in Russia. The results are published in the journal Physics Letters B . The Lab’s Dawn Shaughnessy, Ken Moody, Roger Henderson and Mark Stoyer participated in the experiments.

    Every chemical element comes in the form of different isotopes. These isotopes are distinguished from one another by the number of neutrons in the nucleus, and thus by their mass. The newly discovered isotopes have fewer neutrons and are lighter than the previously known isotopes of the respective elements.

    To date, the known Periodic Table comprises more than 3,000 isotopes of 114 confirmed chemical elements.

    Periodic Table 2014
    Periodic Table of elements, 2014, NIST

    According to scientific estimates, more than 4,000 additional, undiscovered isotopes also should exist. Due to their low number of neutrons, their structure is very exotic and therefore interesting for the development of theoretical models describing atomic nuclei.

    “These results really push what we know about nuclear structure to the extreme, neutron-deficient end of the chart of the nuclides,” Shaughnessy said. “When you realize that naturally occurring uranium has 146 neutrons and this new isotope only has 124 neutrons, it shows how much more we still have yet to learn about nuclear structure and the forces that hold the nucleus together.”

    Scientists at LLNL have been involved in heavy element research since the Laboratory’s inception in 1952 and have been collaborators in the discovery of six elements — 113, 114 (Flerovium), 115, 116 (Livermorium), 117 and 118.

    Apart from discoveries themselves, the discovery is the first proof of the new technique for production of these exotic nuclides.

    For the experiment, the scientists shot at a 300-nanometer-thick foil of curium with accelerated calcium nuclei. In the collisions studied, the atomic nuclei of the two elements touched and formed a compound system for an extremely short time.

    Before the compound system could break apart again, after about a sextillionth of a second, the two nuclei involved exchanged a number of their nuclear building-blocks — protons and neutrons. Different isotopes formed as the end products of this exchange.

    The isotopes of berkelium, neptunium, uranium and americium discovered were created as the end products of such collisions. They are unstable and decay after a few milliseconds or seconds, depending on the isotope. All of the resulting decay products can be separated and analyzed using special filters composed of electrical and magnetic fields. The scientists used all of the decay products detected to identify the new isotope that has been created.

    The current experiments will make it possible to explore previously unknown areas on the isotope chart. The elements 107 to 112 were discovered using the same experimental facility at GSI.

    See the full article here .

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    LLNL Campus

    Operated by Lawrence Livermore National Security, LLC, for the Department of Energy’s National Nuclear Security
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