1,176 research outputs found

    Gamma ray production cross sections in proton induced reactions on natural Mg, Si and Fe targets over the proton energy range 30 up to 66 MeV

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    Gamma-ray excitation functions have been measured for 30, 42, 54 and 66 MeV proton beams accelerated onto C + O (Mylar), Mg, Si, and Fe targets of astrophysical interest at the separate-sector cyclotron of iThemba LABS in Somerset West (Cape Town, South Africa). A large solid angle, high energy resolution detection system of the Eurogam type was used to record Gamma-ray energy spectra. Derived preliminary results of Gamma-ray line production cross sections for the Mg, Si and Fe target nuclei are reported and discussed. The current cross section data for known, intense Gamma-ray lines from these nuclei consistently extend to higher proton energies previous experimental data measured up to Ep ~ 25 MeV at the Orsay and Washington tandem accelerators. Data for new Gamma-ray lines observed for the first time in this work are also reported.Comment: 11 pages, 6 figures. IOP Institute of Physics Conference Nuclear Physics in Astrophysics VII, 28th EPF Nuclear Physics Divisional Conference, May 18-22 2015, York, U

    Second T = 3/2 state in 9^9B and the isobaric multiplet mass equation

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    Recent high-precision mass measurements and shell model calculations~[Phys. Rev. Lett. {\bf 108}, 212501 (2012)] have challenged a longstanding explanation for the requirement of a cubic isobaric multiplet mass equation for the lowest A=9A = 9 isospin quartet. The conclusions relied upon the choice of the excitation energy for the second T=3/2T = 3/2 state in 9^9B, which had two conflicting measurements prior to this work. We remeasured the energy of the state using the 9Be(3He,t)^9{\rm Be}(^3{\rm He},t) reaction and significantly disagree with the most recent measurement. Our result supports the contention that continuum coupling in the most proton-rich member of the quartet is not the predominant reason for the large cubic term required for A=9A = 9 nuclei

    Jellyfish stings trigger gill disorders and increased mortality in farmed sparus aurata (linnaeus, 1758) in the mediterranean sea

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    Jellyfish are of particular concern for marine finfish aquaculture. In recent years repeated mass mortality episodes of farmed fish were caused by blooms of gelatinous cnidarian stingers, as a consequence of a wide range of hemolytic, cytotoxic, and neurotoxic properties of associated cnidocytes venoms. The mauve stinger jellyfish Pelagia noctiluca (Scyphozoa) has been identified as direct causative agent for several documented fish mortality events both in Northern Europe and the Mediterranean Sea aquaculture farms. We investigated the effects of P. noctiluca envenomations on the gilthead sea bream Sparus aurata by in vivo laboratory assays. Fish were incubated for 8 hours with jellyfish at 3 different densities in 300 l experimental tanks. Gill disorders were assessed by histological analyses and histopathological scoring of samples collected at time intervals from 3 hours to 4 weeks after initial exposure. Fish gills showed different extent and severity of gill lesions according to jellyfish density and incubation time, and long after the removal of jellyfish from tanks. Jellyfish envenomation elicits local and systemic inflammation reactions, histopathology and gill cell toxicity, with severe impacts on fish health. Altogether, these results shows P. noctiluca swarms may represent a high risk for Mediterranean finfish aquaculture farms, generating significant gill damage after only a few hours of contact with farmed S. aurata. Due to the growth of the aquaculture sector and the increased frequency of jellyfish blooms in the coastal waters, negative interactions between stinging jellyfish and farmed fish are likely to increase with the potential for significant economic losses

    Electrodeposition of nanocrystalline Ni-Mo alloys from alkaline glycinate solutions

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    The induced electrodeposition of nanocrystalline Ni-Mo alloys was investigated using two different molar ratios of Ni:Mo in sodium glycinate solution at pH 9.3. The chemical nature of the Ni2+ and MoO4 2- in alkaline glycinate solution was studied using UV-Vis absorption spectroscopy. The composition of the coating layer was determined using EDX. The crystallinity of electrodeposits was examined using XRD, whereas, the morphology and topography were investigated using SEM and AFM, respectively. The corrosion resistance of Ni-Mo alloys compared to pure Ni was studied in 3.5 % NaCl solution using potentiodynamic polarization and electrochemical impedance techniques. Ni-Mo alloy electrodeposited from the solution containing [MoO4 2-]/[Ni2+] molar ratio of 0.2 show higher corrosion resistance compared to plating solutions of molar ratio 0.1 and pure Ni.NPRP Grant 4-306-2-111 from the Qatar National Research Fund (a Member of The Qatar Foundation).Scopu

    Analysis of component-based approaches toward componentized 5G

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    5G is expected to be modular by design toward autonomic and agile networks. In this regards, the 5G functional architecture is designed as service-based seeking to support the concept of Network Slicing. This leads us to the question: what componentization approach to implement this modular architecture? Is there a componentization approach that is suitable for all the network functions? Which design approach will help to have autonomic and cognitive networks? In this paper we shed the light on the different component-based approaches. In addition, we reviewed the state of the art addressing the applicability of component-based approaches to build autonomic networks. Therefore, we present discussion, comparison and synthesis as input to 5G related activities

    Perspectives on utilization of edible coatings and nano-laminate coatings for extension of postharvest storage of fruits and vegetables

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    It is known that in developing countries, a large quantity of fruit and vegetable losses results at postharvest and processing stages due to poor or scarce storage technology and mishandling during harvest. The use of new and innovative technologies for reducing postharvest losses is a requirement that has not been fully covered. The use of edible coatings (mainly based on biopolymers) as a postharvest technique for agricultural commodities has offered biodegradable alternatives in order to solve problems (e.g., microbiological growth) during produce storage. However, biopolymer-based coatings can present some disadvantages such as: poor mechanical properties (e.g., lipids) or poor water vapor barrier properties (e.g., polysaccharides), thus requiring the development of new alternatives to solve these drawbacks. Recently, nanotechnology has emerged as a promising tool in the food processing industry, providing new insights about postharvest technologies on produce storage. Nanotechnological approaches can contribute through the design of functional packing materials with lower amounts of bioactive ingredients, better gas and mechanical properties and with reduced impact on the sensorial qualities of the fruits and vegetables. This work reviews some of the main factors involved in postharvest losses and new technologies for extension of postharvest storage of fruits and vegetables, focused on perspective uses of edible coatings and nano-laminate coatings.María L. Flores-López thanks Mexican Science and Technology Council (CONACYT, Mexico) for PhD fellowship support (CONACYT Grant Number: 215499/310847). Miguel A. Cerqueira (SFRH/BPD/72753/2010) is recipient of a fellowship from the Fundação para a Ciência e Tecnologia (FCT, POPH-QREN and FSE Portugal). The authors also thank the FCT Strategic Project of UID/ BIO/04469/2013 unit, the project RECI/BBB-EBI/0179/2012 (FCOMP-01-0124-FEDER-027462) and the project ‘‘BioInd Biotechnology and Bioengineering for improved Industrial and AgroFood processes,’’ REF. NORTE-07-0124-FEDER-000028 Co-funded by the Programa Operacional Regional do Norte (ON.2 – O Novo Norte), QREN, FEDER. Fundação Cearense de Apoio ao Desenvolvimento Científico e Tecnológico – FUNCAP, CE Brazil (CI10080-00055.01.00/13)
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