Ion counting efficiencies at the IGISOL facility

At the IGISOL-JYFLTRAP facility, fission mass yields can be studied at high precision. Fission fragments from a U target are passing through a Ni foil and entering a gas filled chamber. The collected fragments are guided through a mass separator to a Penning trap where their masses are identified. This simulation work focuses on how different fission fragment properties (mass, charge and energy) affect the stopping efficiency in the gas cell. In addition, different experimental parameters are varied (e. g. U and Ni thickness and He gas pressure) to study their impact on the stopping efficiency. The simulations were performed using the Geant4 package and the SRIM code. The main results suggest a small variation in the stopping efficiency as a function of mass, charge and kinetic energy. It is predicted that heavy fragments are stopped about 9% less efficiently than the light fragments. However it was found that the properties of the U, Ni and the He gas influences this behavior. Hence it could be possible to optimize the efficiency.Comment: 52 pages, 44 figure

The dynamics of two-phase flow in vapour generators

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Characterization of a Be(p,xn) neutron source for fission yields measurements

We report on measurements performed at The Svedberg Laboratory (TSL) to characterize a proton-neutron converter for independent fission yield studies at the IGISOL-JYFLTRAP facility (Jyv\"askyl\"a, Finland). A 30 MeV proton beam impinged on a 5 mm water-cooled Beryllium target. Two independent experimental techniques have been used to measure the neutron spectrum: a Time of Flight (TOF) system used to estimate the high-energy contribution, and a Bonner Sphere Spectrometer able to provide precise results from thermal energies up to 20 MeV. An overlap between the energy regions covered by the two systems will permit a cross-check of the results from the different techniques. In this paper, the measurement and analysis techniques will be presented together with some preliminary results.Comment: 3 pages, 3 figures, also submitted as proceedings of the International Conference on Nuclear Data for Science and Technology 201

Solidarity bridges: alternative food economies in urban Greece

Εστιάζοντας στο αστικό-περιφερειακό συνεχές στο χώρο της Θεσσαλονίκης, αυτή η μελέτη διερευνά τις απτές κοινωνικές δραστηριότητες ορισμένων ομάδων που έχουν αφοσιωθεί στο χτίσιμο μιας «κοινωνικής οικονομίας» διανομής τροφής χωρίς μεσάζοντες. Τα εθνογραφικά δεδομένα (που συνέλεξα μεταξύ 2013-2015), αφορούν τις από-τα-κάτω απαντήσεις προς τις δυσκολίες που ζουν οι άνθρωποι σε ζητήματα των τα προς το ζην τους ζητημάτων. Στο φως αυτών των δεδομένων, προτείνω να ανοίξουμε τα εννοιολογικά όρια της αμοιβαιότητας, έτσι ώστε να συμπεριλάβουμε την αλληλεγγύη, ως ημική έννοια με πολιτισμικές συμπαραδηλώσεις συγκυριακές της κρίσης. Η «οικονομία αλληλεγγύης» μπορεί να ιδωθεί ως μια εννοιακή και πολιτική γέφυρα που συμβολικά, αλλά και υλικά, φέρνει κοντά κοινότητες παραγωγής και κατανάλωσης τροφής. Η έννοια του «χωριού» είναι μια πρωτότυπη μετωνυμία που χρησιμοποιούν οι αστοί ακτιβιστές στα συστήματα διανομής τους, για να δηλώσουν μια συγκεκριμένη κοσμολογία σχέσης με το φαγητό και τα υλικά διατροφής. Η έννοια επικαιροποιείται με σημαίνοντες τρόπους, στην παρούσα συγκυρία λιτότητας στη χώρα.    Set in the urban-rural continuum of Thessaloniki, this paper explores the grounded social activities of certain groups, committed to building a social economy of distributing food without intermediaries. In the light of new ethnographic data from grassroots responses to livelihoods’ hardship, I propose to expand reciprocity's conceptual boundaries, extended to include a local concept rampant in crisis-ridden Greece: solidarity. The solidarity economy can be seen as a conceptual and political bridge that symbolically as well as materially brings together communities of food production and consumption. The cosmology of the horio (village) is an unexpected urban activist metonym in the food distribution systems that have emerged amidst austerity measures in Greece

Alison Sánchez Hall, All or none: Cooperation and sustainability in Italy’s red belt, New York-Oxford, Berghahn, 2018, pp. 300

Book review of Alison Sánchez Hall, All or none: Cooperation and sustainability in Italy’s red belt, New York-Oxford, Berghahn, 2018, pp. 300.Recensione di Alison Sánchez Hall, All or none: Cooperation and sustainability in Italy’s red belt, New York-Oxford, Berghahn, 2018, pp. 300

On divisionism and cypriotism: the civic languages of the Cyprus Problem

This article analyses the two main vernacular poles through which the Greek-Cypriot population engages with statehood, and thus the Cyprus Problem. Using ethnography, I dissect two versions of “nationalist” cultural ethos, which, while pertinent to the post-colonial condition generally, are largely unknown outside Cyprus. These concern on the one hand the idea of divisionism and on the other that of cypriotism. I specifically show how the bicommunal nature of the state in Cyprus finds emic continuity among certain Greek-Cypriots that adhere to a non-nation-bound loyalty glossed as cypriotism, while I illustrate how dividing techniques of conventional nationalist rhetoric operate among other Greek-Cypriots. I also briefly discuss how such vernacular experiences of nationhood and statehood reverberate among Turkish-Cypriots and Turks (the state’s “Others”) and consider the ways this affects the Republic. The article therefore contributes to understanding the political vernacular in the post-colonial and post-conflict context of Cyprus, and highlights from below the local “languages” pertaining to the Cyprus Problem

Solidarity bridges: alternative food economies in urban Greece

Εστιάζοντας στο αστικό-περιφερειακό συνεχές στο χώρο της Θεσσαλονίκης, αυτή η μελέτη διερευνά τις απτές κοινωνικές δραστηριότητες ορισμένων ομάδων που έχουν αφοσιωθεί στο χτίσιμο μιας «κοινωνικής οικονομίας» διανομής τροφής χωρίς μεσάζοντες. Τα εθνογραφικά δεδομένα (που συνέλεξα μεταξύ 2013-2015), αφορούν τις από-τα-κάτω απαντήσεις προς τις δυσκολίες που ζουν οι άνθρωποι σε ζητήματα των τα προς το ζην τους ζητημάτων. Στο φως αυτών των δεδομένων, προτείνω να ανοίξουμε τα εννοιολογικά όρια της αμοιβαιότητας, έτσι ώστε να συμπεριλάβουμε την αλληλεγγύη, ως ημική έννοια με πολιτισμικές συμπαραδηλώσεις συγκυριακές της κρίσης. Η «οικονομία αλληλεγγύης» μπορεί να ιδωθεί ως μια εννοιακή και πολιτική γέφυρα που συμβολικά, αλλά και υλικά, φέρνει κοντά κοινότητες παραγωγής και κατανάλωσης τροφής. Η έννοια του «χωριού» είναι μια πρωτότυπη μετωνυμία που χρησιμοποιούν οι αστοί ακτιβιστές στα συστήματα διανομής τους, για να δηλώσουν μια συγκεκριμένη κοσμολογία σχέσης με το φαγητό και τα υλικά διατροφής. Η έννοια επικαιροποιείται με σημαίνοντες τρόπους, στην παρούσα συγκυρία λιτότητας στη χώρα.    Set in the urban-rural continuum of Thessaloniki, this paper explores the grounded social activities of certain groups, committed to building a social economy of distributing food without intermediaries. In the light of new ethnographic data from grassroots responses to livelihoods’ hardship, I propose to expand reciprocity's conceptual boundaries, extended to include a local concept rampant in crisis-ridden Greece: solidarity. The solidarity economy can be seen as a conceptual and political bridge that symbolically as well as materially brings together communities of food production and consumption. The cosmology of the horio (village) is an unexpected urban activist metonym in the food distribution systems that have emerged amidst austerity measures in Greece

Manipulating modern diesel engine particulate emission characteristics through butanol fuel blending and fuel injection strategies for efficient diesel oxidation catalysts

Decoupling the dependences between emission reduction technologies and engine fuel economy in order to improve them both simultaneously has been proven a major challenge for the vehicle research communities. Additionally, the lower exhaust gas temperatures associated with the modern and future generation internal combustion engines are challenging the performance of road transport environmental catalysts. Studying how fuel properties and fuel injection strategies affect the combustion characteristics, emissions formation and hence catalysts performance can unveil synergies that can benefit vehicle emissions and fuel economy and as well as guide the design of next generation sustainable fuels. The experimental work presented here was conducted using a modern single-cylinder, common rail fuel injection system diesel engine equipped with a diesel oxidation catalyst (DOC). The impact of the fuel post-injection strategy that is commonly used as part of the aftertreatment system function (i.e. regeneration of diesel particulate filters or activity in hydrocarbon selective reduction of NOX), combined with butanol-diesel fuel blend (B20) combustion on engine emissions formation, particulate matter characteristics (size distribution, morphology and structure) and oxidation catalyst activity were studied. It was found that post-injection produced lower PM concentration and modified the soot morphological parameters by reducing the number of primary particles (npo), the radius of gyration (Rg), and the fractal dimension (Df). The results were compared with the engine operation on diesel fuel. The increased concentration of HC and CO in the exhaust as a result of the diesel fuel post-injection at the studied exhaust conditions (i.e. T = 300 °C) led in the reduction of the DOC activity due to the increased competition of species for active sites. This effect was improved the combustion of B20 when compared to diesel.Publisher Statement: NOTICE: this is the author’s version of a work that was accepted for publication in Applied Energy. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Applied Energy, [190, (2017)] DOI: 10.1016/j.apenergy.2016.12.102© 2017, Elsevier. Licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International http://creativecommons.org/licenses/by-nc-nd/4.0/<br/

Experimental assessment for instantaneous temperature and heat flux measurements under Diesel motored engine conditions

The main goal of this work is to validate an innovative experimental facility and to establish a methodology to evaluate the influence of some of the engine parameters on local engine heat transfer behaviour under motored steady-state conditions. Instantaneous temperature measurements have been performed in order to estimate heat fluxes on a modified Diesel single cylinder combustion chamber. This study was divided into two main parts. The first one was the design and setting on of an experimental bench to reproduce Diesel conditions and perform local-instantaneous temperature measurements along the walls of the combustion chamber by means of fast response thermocouples. The second one was the development of a procedure for temperature signal treatment and local heat flux calculation based on one-dimensional Fourier analysis. A thermodynamic diagnosis model has been employed to characterise the modified engine with the new designed chamber. As a result of the measured data coherent findings have been obtained in order to understand local behaviour of heat transfer in an internal combustion engine, and the influence of engine parameters on local instantaneous temperature and heat flux, have been analysed. © 2011 Elsevier Ltd. All rights reserved.Torregrosa, AJ.; Bermúdez, V.; Olmeda González, PC.; Figueroa Garcia, OL. (2012). Experimental assessment for instantaneous temperature and heat flux measurements under Diesel motored engine conditions. Energy Conversion and Management. 54(1):57-66. doi:10.1016/j.enconman.2011.10.009S576654