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  1. Abstract

    The 20th century started with the realization that working together and collaborating expedites new discoveries. The Solvay Conference in 1911 brought together scientists to try to understand the real nature of matter, the new elements, and their properties. Through global conflicts, the scientists stayed in communication and organized IUPAC and IUPAP to stay current in advances internationally in chemistry and physics, respectively. The outcomes include the discovery and naming of the elements that complete the periodic table of elements and the chart of nuclides with the heavy atoms and all of their isotopes. Mary Lowe Good forged new directions in developing tools in the field of radiochemistry. She exemplified cooperation and collaboration nationally and internationally. Now the advances in the heavy elements by Yuri Ts. Oganessian and colleagues staying close to the principles of international cooperation and sharing the new information about the connection of the production of super heavy elements to the main part of the chart of nuclides. The future lies in determining whether there are more elements to be discovered and what are their chemical properties.

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    Free, publicly-accessible full text available October 5, 2024
  2. Free, publicly-accessible full text available November 1, 2024
  3. Abstract

    The nucleus is a complex many-body system with some remarkable emergent collective properties of multiple nucleons acting together. Bohr and Mottelson [1] provided a description of collective motion in nuclei based on geometrical shapes with superimposed oscillations around those shapes. Later, Lie algebras and symmetries were used to describe nuclear dynamics [2], followed by advances in the shell model approach [3] with new effective nucleon-nucleon two- and three-body interactions, and more recently with Hartree-Fock-Bogoliubov approximations within the extended generator coordinate method [4]. Yet, the underlying science question has remained the same. In nuclei, where there is explicit deformation in the ground state, “are the low-lying 0+states collective vibrations built on the ground state or are they minima of a coexisting shape?” Ref. [4] has shown that for a significant percentage ofK= 0+excitations built on the deformed ground state (g.s.) should, in fact, be a collective vibration. The question has remained open due to sufficiently convincing experimental data with lifetimes, transfer reaction cross sections, andE0 transitions [5]. This paper summarizes the experimental situation regarding the lifetimes of 0+states.

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    Free, publicly-accessible full text available October 1, 2024
  4. Free, publicly-accessible full text available October 1, 2024
  5. Free, publicly-accessible full text available July 1, 2024
  6. Benjamin Franklin was a preeminent proponent of the new colonial and Continental paper monetary system in 18th-century America. He established a network of printers, designing and printing money notes at the same time. Franklin recognized the necessity of paper money in breaking American dependence on the British trading system, and he helped print Continental money to finance the American War of Independence. We use a unique combination of nondistractive, microdestructive, and advanced atomic-level imaging methods, including Raman, Infrared, electron energy loss spectroscopy, X-ray diffraction, X-ray fluorescence, and aberration-corrected scanning transmission electron microscopy, to analyze pre-Federal American paper money from the Rare Books and Special Collections of the Hesburgh Library at the University of Notre Dame. We investigate and compare the chemical compositions of the paper fibers, the inks, and fillers made of special crystals in the bills printed by Franklin’s printing network, other colonial printers, and counterfeit money. Our results reveal previously unknown ways that Franklin developed to safeguard printed money notes against counterfeiting. Franklin used natural graphite pigments to print money and developed durable “money paper” with colored fibers and translucent muscovite fillers, along with his own unique designs of “nature-printed” patterns and paper watermarks. These features and inventions made pre-Federal American paper currency an archetype for developing paper money for centuries to come. Our multiscale analysis also provides essential information for the preservation of historical paper money.

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    Free, publicly-accessible full text available July 25, 2024
  7. Schumann, D. ; Stodel, C. ; Gott, M. (Ed.)

    A simple and efficient target preparation method is developed combining spin coating and solution combustion synthesis. Multiple smooth and uniform UO2targets have been prepared using this method on a variety of backings (aluminium, carbon, silicon) used in nuclear physics experiments. The thicknesses of the targets can be precisely tuned by changing the number of coatings within the range of ~50-1000 µm/cm2. These targets are highly uniform (<5% deviation), robust, and remain strongly adherent to their backings even after being irradiated by high doses (1017ions/ cm2) of 1.7 MeV Ar2+ions.

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