511 research outputs found

    Rotational Bands and Electromagnetic Transitions of some even-even Neodymium Nuclei in J-Projected Hartree-Fock Model

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    Rotational structures of even-even 148−160^{148-160}Nd nuclei are studied with the self-consistent deformed Hartree-Fock (HF) and angular momentum (J) projection model. Spectra of ground band, recently observed K=4−K=4^{-}, K=5−K=5^{-} and a few more excited, positive and negative parity bands have been studied upto high spin values. Apart from these detailed electromagnetic properties (like E2, M1 matrix elements) of all the bands have been obtained. There is substantial agreement between our model calculations and available experimental data. Predictions are made about the band structures and electromagnetic properties of these nuclei. Some 4-qasiparticle K-isomeric bands and their electromagnetic properties are predicted.Comment: 20 page

    High-spin parity doublets in the nucleus 151 Pm

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    The high-spin-level structure of the nucleus 151Pm has been investigated by in-beam γ-ray spectroscopy using the 150Nd(α, p2N) 151Pm reaction. The observed enhanced E1 transitions with B(E1) of the order of 10-3 W.u. and parity doubling, both features characteristic of a reflection-asymmetric mean field, suggest an octupole deformation in 61151P

    DSAM lifetime measurements for the chiral pair in 194Tl

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    Most important for the identification of chiral symmetry in atomic nuclei is to establish a pair of bands that are near-degenerate in energy, but also in B(M1) and B(E2) transition probabilities. Dedicated lifetime measurements were performed for four bands of 194Tl, including the pair of four-quasiparticle chiral bands with close near-degeneracy, considered as a prime candidate for best chiral symmetry pair. The lifetime measurements confirm the excellent near-degeneracy in this pair and indicate that a third band may be involved in the chiral symmetry scenario

    Coexistence of 'alpha+ 208Pb' cluster structures and single-particle excitations in 212Po

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    Excited states in 212Po have been populated by alpha transfer using the 208Pb(18O,14C) reaction at 85MeV beam energy and studied with the EUROBALL IV gamma multidetector array. The level scheme has been extended up to ~ 3.2 MeV excitation energy from the triple gamma coincidence data. Spin and parity values of most of the observed states have been assigned from the gamma angular distributions and gamma -gamma angular correlations. Several gamma lines with E(gamma) < 1 MeV have been found to be shifted by the Doppler effect, allowing for the measurements of the associated lifetimes by the DSAM method. The values, found in the range [0.1-0.6] ps, lead to very enhanced E1 transitions. All the emitting states, which have non-natural parity values, are discussed in terms of alpha-208Pb structure. They are in the same excitation-energy range as the states issued from shell-model configurations.Comment: 21 pages, 19 figures, corrected typos, revised arguments in Sect. III

    Managing the Life Cycle to Reduce Environmental Impacts

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    Reasoning with heuristics

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    Which rules should guide our reasoning? Human reasoners often use reasoning shortcuts, called heuristics, which function well in some contexts but lack the universality of reasoning rules like deductive implication or inference to the best explanation. Does it follow that human reasoning is hopelessly irrational? I argue: no. Heuristic reasoning often represents human reasoners reaching a local rational maximum, reasoning more accurately than if they try to implement more “ideal” rules of reasoning. I argue this is a genuine rational achievement. Our ideal rational advisors would advise us to reason with heuristic rules, not more complicated ideal rules. I argue we do not need a radical new account of epistemic norms to make sense of the success of heuristic reasoning

    Stable triaxiality at the highest spins in 138 Nd and 139 Nd

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    The nuclei 138Nd{}^{138}\mathrm{Nd} and 139Nd{}^{139}\mathrm{Nd} have been studied at very high spins via the 48Ca+94Zr{}^{48}\mathrm{Ca}{+}^{94}\mathrm{Zr} reaction. Several new rotational bands were observed, four in 138Nd{}^{138}\mathrm{Nd} and two in 139Nd.{}^{139}\mathrm{Nd}. The J(2){J}^{(2)} moments of inertia calculated from the observed \ensuremath{\gamma}-ray energies are very small and almost constant, indicating that these bands are triaxial. Cranked Nilsson-Strutinsky calculations reproduce the general behavior of the bands, supporting this interpretation and suggesting an approximately constant \ensuremath{\gamma} value of \ensuremath{\sim}+35\ifmmode^\circ\else\textdegree\fi{} over a large spin range up to the highest observed spins. These bands and a few similar bands in other nuclei of the N\ensuremath{\approx}80 region are a unique example of almost undisturbed triaxial bands

    Relating industrial symbiosis and circular economy to the sustainable development debate

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    Industrial Symbiosis (IS) is a business-focused collaborative approach oriented towards resource efficiency that has been theorised and studied mainly over the last twenty-five years. Recently, IS seems to have found a renewed impetus in the framework of the Circular Economy (CE), a novel approach to sustainability and Sustainable Development (SD) that has been rapidly gaining momentum world-wide. This opening chapter of the book provides an introduction to the concepts of IS, CE and SD, and summarizes their complex evolutionary paths, recalling the rel-evant developments and implementation challenges. In addition, the authors point out the divergences and interrelations of these concepts, both among themselves and with other related concepts and research fields, such as industrial ecology, eco-logical modernization and the green economy. Furthermore, the potential contribu-tion of IS and the CE to SD is briefly discussed, also highlighting critical issues and trade-offs, as well as gaps in research and application, especially relating to the so-cial component of sustainability. Particular attention is given to the potential role of IS in the achievement of targets connected to the Sustainable Development Goals set in the UN Agenda 2030. The recent advances in the IS and CE discussion in the context of the SD research community are further explored, with particular empha-sis on the contribution of the International Sustainable Development Research So-ciety (ISDRS) and its 24th annual conference organised in Messina, Italy, in 2018. The programme of that conference, indeed, included specific tracks on the above-mentioned themes, the contents of which are briefly commented on here, after an overview on the whole conference and the main cross-cutting concepts emerged. In the last part of the chapter, a brief description of the chapters collected in the book is presented. These contributions describe and discuss theoretical frameworks, methodological approaches and/or experiences and case studies where IS and the principles of CE are applied in different geographical context and at different scales to ultimately improve the sustainability of the current production patterns
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