994 research outputs found

    Magnetocatalytic Adiabatic Spin Torque Orbital Transformations for Novel Chemical and Catalytic Reaction Dynamics: The Little Effect

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    In this manuscript the theory and phenomena associated with the Little Effect are introduced as the spin induced orbital dynamics of confined fermions under strong magnetic and thermal environments. This Little Effect is considered in details for the electron transfer reactions associated with redox processes of Cu-Ag alloy within deionized water and for the orbital dynamics during the iron catalyzed covalent bond rearrangements associated with amorphous carbon conversion to diamond. Furthermore, prolong extreme conditions of 74,000 amps, 403 V, strong Lorentz compression, and thermal stresses upon this Cu-Ag- H2O system on the basis of the Little Effect of high spin, thermally induced orbital dynamics are predicted and demonstrated to cause the magnetically organized reverse beta, electron capture, proton capture and neutron capture processes for various infrequent pycnonuclear transmutations within the Cu-Ag coil. The general experimental verification and the broad implications of this Little Effect on chemistry are demonstrated within these two ideal systems: an ionic case and a molecular case. The Little Effect is contrasted with the Hedvall Effect as a dynamical phenomenon causing the kinematics of the Hedvall Effect. The compatibility of the Little Effect with the Woodward-Hoffmann Rule is demonstrated. The Little Effect provides greater understanding of order in systems far from equilibrium. The implications of the Little Effect for other interesting phenomena such as ferromagnetism, unconventional magnetism, superparamagnetism, superconductivity, and pycnonuclear effects are concluded

    Rotating stars

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    A Transient Thermal and Structural Analysis of Fuel in the Annular Core Research Reactor

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    The health of a nuclear reactor’s fuel is essential to the operational longevity of the reactor. The health of the fuel in the Annular Core Research Reactor (ACRR) is a topic of increased interest due to both a proposed new facility that would include the ACRR and the recent resurfacing of contradictory reports regarding thermal stresses in its fuel pellets. Unlike other reactor fuels, which are widely used and well-characterized, the fuel in the ACRR is unique. The ACRR’s fuel elements consist of UO­2-BeO fuel pellets, fluted niobium refractory liners, and stainless-steel cladding. The purpose of this thesis is to examine the thermal stresses in the ACRR’s peak fuel pellets under maximum pulse conditions. Because the properties are not well-characterized, the material properties of the fresh fuel pellets were first determined using approximations including the rule of mixtures and the Voigt-Reuss-Hill approximation. Then the material properties were adjusted to account for the effects of burnup and radiation. Next a transient thermal analysis was performed using the commercial finite element code ANSYS Mechanical 19.2. The temperature gradients calculated in the transient thermal analysis were used to calculate the thermal stresses in the fuel pellets. The thermal stresses were also calculated using ANSYS Mechanical 19.2. Using the same process, a material sensitivity study was performed to examine the sensitivity of the thermal stresses to the material properties. Finally, the effects of the thermal stresses were examined from a fracture mechanics perspective. The analyses showed that the fuel pellets experience large thermal stresses that are caused by the fuel element’s unique geometry. Despite the large thermal stresses, it was concluded that the thermal stresses are unlikely to cause fracture

    Stellar structure and compact objects before 1940: Towards relativistic astrophysics

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    Since the mid-1920s, different strands of research used stars as "physics laboratories" for investigating the nature of matter under extreme densities and pressures, impossible to realize on Earth. To trace this process this paper is following the evolution of the concept of a dense core in stars, which was important both for an understanding of stellar evolution and as a testing ground for the fast-evolving field of nuclear physics. In spite of the divide between physicists and astrophysicists, some key actors working in the cross-fertilized soil of overlapping but different scientific cultures formulated models and tentative theories that gradually evolved into more realistic and structured astrophysical objects. These investigations culminated in the first contact with general relativity in 1939, when J. Robert Oppenheimer and his students George Volkoff and Hartland Snyder systematically applied the theory to the dense core of a collapsing neutron star. This pioneering application of Einstein's theory to an astrophysical compact object can be regarded as a milestone in the path eventually leading to the emergence of relativistic astrophysics in the early 1960s.Comment: 83 pages, 4 figures, submitted to the European Physical Journal

    The methods of natural inquiry during the sixteenth-century: Bartolomeo Maranta and Ferrante Imperato

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    The present dissertation focuses on the examination of the methods of natural inquiry during the sixteenth-century. The historico-epistemological analysis of the different methodologies, which naturalists used to read the book of nature, shows that natural history, medicine, and alchemy were closely interconnected during the sixteenth-century. How did the naturalist thinkers justify and validate their knowledge? The present dissertation answers this question by means of two relevant historical examples of the pharmaceutical domain: Maranta’s theriac and Imperato’s philosophical medicine. They both show the way in which experience and authority actually interacted within the naturalistic discourse of the sixteenth-century. In other words, the dissertation shows how experience aided naturalist philosophers to interpret correctly authorities and vice versa; more importantly, it shows under which circumstances experience could dethrone authority. In this manner, one can understand how the methods of natural inquiry justify and validate the pharmaceutical agenda of the sixteenth-century

    Cosmology

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    Meteorites and a Young Earth

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    Major advance in relating a young-earth creationist viewpoint to scientific data has come from recognition that radioisotope age may be a significant characteristic of an object and yet not have direct real-time significance in the history of that object. Igneous and !\u3eedimentary material may have a radioisotope age that is an inherited characteristic and not related to its present placement. It is more difficult to accommodate a young-earth perspective to extraterrestrial objects. High energy atomic nuclei from outer space - cosmic rays - produce cosmogenic nuclides in meteorites and on the surface of the Moon. The accumulation of identifiable cosmogenic nuclides may be related to cosmic-ray intensity to obtain a cosmic-ray exposure age. Cosmic-ray exposure ages that have been determined range from about 900 thousand to about 2.4 billion years. This range has been interpreted to suggest continuing impact of meteoroids on the surface of the Moon, and continuing breakup of large meteoroids into smaller objects. The concepts of cosmic-ray exposure and radioisotope age are particularly well illustrated by the meteorite Asuka-881757, which has been classified as having originated from a meteoroid impact on the Moon. Six independent radioisotope age determinations for Asuka- 881757 average 3843 ±56 (20) million years. Its cosmic-ray exposure age is - 900 thousand years. Five proposals for accommodating these data are considered. At one extreme Asuka-881757 may be classified as an object from outside the Solar System, from a region in the Milky Way galaxy for which 3.9 billion years has the same significance as 4.6 billion years has for radioisotope ages within the Solar System. At the other extreme of the five proposals all radioisotope ages and cosmic-ray exposure ages greater than - 10,000 years are considered to represent initial characteristics that God placed within minerals at their creation

    A study on the use of vocal samples and vocal transformation techniques in the music of Paul Lansky and Trevor Wishart

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    For most, the spoken word holds no more, and no less, an interest other than the implied meaning of the word, while for others, the interest lies in the inherent wealth of sonic substance in that sound. This study is focused on the composers Paul Lansky and Trevor Wishart, their compositions and the compositional processes whereby which they utilise the wealth of sonic possibilities inherent in the human voice in general and in particular the sound of the spoken word in everyday speech and conversations. Focusing in particular on Lansky’s Smalltalk (1988) and Wishart’s Vox 5 (1986), the majority of the content is concentrated on exploring issues of inspiration and origin, contexts of use and compositional aims, and the technology, procedures and techniques related to the electroacoustic compositions of Lansky and Wishart, as well as on the technological developments directly and indirectly brought about by both composers in their efforts to achieve the results that they desired
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