Tetrahydroborates: development and potential as hydrogen storage medium

The use of fossil fuels as an energy supply becomes increasingly problematic from the point of view of both environmental emissions and energy sustainability. As an alternative, hydrogen is widely regarded as a key element for a potential energy solution. However, different from fossil fuels such as oil, gas, and coal, the production of hydrogen requires energy. Alternative and intermittent renewable sources such as solar power, wind power, etc., present multiple advantages for the production of hydrogen. On one hand, the renewable sources contribute to a remarkable reduction of pollutants released to the air. On the other hand, they significantly enhance the sustainability of energy supply. In addition, the storage of energy in form of hydrogen has a huge potential to balance an effective and synergetic utilization of the renewable energy sources. In this regard, hydrogen storage technology presents a key roadblock towards the practical application of hydrogen as “energy carrier”. Among the methods available to store hydrogen, solid-state storage is the most attractive alternative both from the safety and the volumetric energy density points of view. Because of their appealing hydrogen content, complex hydrides and complex hydride-based systems have attracted considerable attention as potential energy vectors for mobile and stationary applications. In this review, the progresses made over the last century on the development in the synthesis and research on the decomposition reactions of homoleptic tetrahydroborates is summarized. Furthermore, theoretical and experimental investigations on the thermodynamic and kinetic tuning of tetrahydroborates for hydrogen storage purposes are herein reviewed.CONICET (Consejo Nacional de Invetigaciones Científicas y Técnicas), ANPCyT—(Agencia Nacional de Promoción Científica y Tecnológica) and CNEA (Comisión Nacional de Energía Atómica). The authors also acknowledge Alexander von Humboldt Foundation (J. Puszkiel fellowship holder, No. 1187279 STP

KNH2 - KH: a metal amide - hydride solid solution

We report for the first time the formation of a metal amide-hydride solid solution. The dissolution of KH into KNH2 leads to an anionic substitution, which decreases the interaction among NH2 - ions. The rotational properties of the high temperature polymorphs of KNH2 are thereby retained down to room temperature.Fil: Santoru, Antonio. Helmholtz-zentrum Geesthacht; Alemania. Università di Torino; ItaliaFil: Pistidda, Claudio. Helmholtz-zentrum Geesthacht; AlemaniaFil: Sørby, Magnus H.. Institute for Energy Technology. Physics Department; NoruegaFil: Chierotti, Michele R.. Università di Torino; ItaliaFil: Garroni, Sebastian. University of Sassari; ItaliaFil: Pinatel, Eugenio. Università di Torino; ItaliaFil: Karimi, Fahim. Helmholtz-zentrum Geesthacht; AlemaniaFil: Cao, Hujun. Helmholtz-zentrum Geesthacht; AlemaniaFil: Bergemann, Nils. Helmholtz-zentrum Geesthacht; AlemaniaFil: Le, Thi T.. Helmholtz-zentrum Geesthacht; AlemaniaFil: Puszkiel, Julián Atilio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte; Argentina. Comisión Nacional de Energía Atómica. Gerencia del Área de Energía Nuclear. Instituto Balseiro; ArgentinaFil: Gobetto, Roberto. Università di Torino; ItaliaFil: Baricco, Marcello. Università di Torino; ItaliaFil: Hauback, Bjorn C.. Institute for Energy Technology. Physics Department; NoruegaFil: Klassen, Thomas. Helmholtz-zentrum Geesthacht; AlemaniaFil: Dornheim, Martín. Helmholtz-zentrum Geesthacht; Alemani

Mechanically activated metathesis reaction in NaNH2–MgH2 powder mixtures

The present work addresses the kinetics of chemical transformations activated by the mechanical processing of powder by ball milling. In particular, attention focuses on the reaction between NaNH2 and MgH2, specific case studies suitably chosen to throw light on the kinetic features emerging in connection with the exchange of anionic ligands induced by mechanical activation. Experimental findings indicate that the mechanical treatment of NaNH2–MgH2 powder mixtures induces a simple metathetic reaction with formation of NaH and Mg(NH2)2 phases. Chemical conversion data obtained by X-ray diffraction analysis have been interpreted using a kinetic model incorporating the statistical character of the mechanical processing by ball milling. The apparent rate constant measuring the reaction rate is related to the volume of powder effectively processed during individual collisions, and tentatively connected with the transfer of mechanical energy across the network formed by the points of contact between the powder particles trapped during collisions.H2020-MSCA-IF-2015 Grant Number #70795

Design of a Nanometric AlTi Additive for MgB2-Based Reactive Hydride Composites with Superior Kinetic Properties

Solid-state hydride compounds are a promising option for efficient and safe hydrogen-storage systems. Lithium reactive hydride composite system 2LiBH4 + MgH2/2LiH + MgB2 (Li-RHC) has been widely investigated owing to its high theoretical hydrogen-storage capacity and low calculated reaction enthalpy (11.5 wt % H2 and 45.9 kJ/mol H2). In this paper, a thorough investigation into the effect of the formation of nano-TiAl alloys on the hydrogen-storage properties of Li-RHC is presented. The additive 3TiCl3·AlCl3 is used as the nanoparticle precursor. For the investigated temperatures and hydrogen pressures, the addition of ∼5 wt % 3TiCl3·AlCl3 leads to hydrogenation/dehydrogenation times of only 30 min and a reversible hydrogen-storage capacity of 9.5 wt %. The material containing 3TiCl3·AlCl3 possesses superior hydrogen-storage properties in terms of rates and a stable hydrogen capacity during several hydrogenation/dehydrogenation cycles. These enhancements are attributed to an in situ nanostructure and a hexagonal AlTi3 phase observed by high-resolution transmission electron microscopy. This phase acts in a 2-fold manner, first promoting the nucleation of MgB2 upon dehydrogenation and second suppressing the formation of Li2B12H12 upon hydrogenation/dehydrogenation cycling.Fil: Le, Thi-Thu. Helmholtz Zentrum Geesthacht; AlemaniaFil: Pistidda, Claudio. Helmholtz Zentrum Geesthacht; AlemaniaFil: Puszkiel, Julián Atilio. Helmholtz Zentrum Geesthacht; Alemania. Comisión Nacional de Energía Atómica. Centro Atómico Bariloche; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte; ArgentinaFil: Castro Riglos, Maria Victoria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte; Argentina. Helmholtz Zentrum Geesthacht; Alemania. Comisión Nacional de Energía Atómica. Centro Atómico Bariloche; ArgentinaFil: Karimi, Fahim. Helmholtz Zentrum Geesthacht; AlemaniaFil: Skibsted, Jørgen. University Aarhus; DinamarcaFil: Gharibdoust, Seyedhosein Payandeh. University Aarhus; DinamarcaFil: Richter, Bo. University Aarhus; DinamarcaFil: Emmler, Thomas. Helmholtz Zentrum Geesthacht; AlemaniaFil: Milanese, Chiara. Università di Pavia; ItaliaFil: Santoru, Antonio. Helmholtz Zentrum Geesthacht; AlemaniaFil: Hoell, Armin. Helmholtz Zentrum Berlin für Materialien und Energie; AlemaniaFil: Krumrey, Michael. Physikalisch Technische Bundesanstalt; AlemaniaFil: Gericke, Eike. Universität zu Berlin; AlemaniaFil: Akiba, Etsuo. Kyushu University; JapónFil: Jensen, Torben R.. University Aarhus; DinamarcaFil: Klassen, Thomas. Helmholtz Zentrum Geesthacht; Alemania. Helmut Schmidt University; AlemaniaFil: Dornheim, Martin. Helmholtz Zentrum Geesthacht; Alemani

Solid state hydrogen storage in alanates and alanate-based compounds: a review

The safest way to store hydrogen is in solid form, physically entrapped in molecular form in highly porous materials, or chemically bound in atomic form in hydrides. Among the different families of these compounds, alkaline and alkaline earth metals alumino-hydrides (alanates) have been regarded as promising storing media and have been extensively studied since 1997, when Bogdanovic and Schwickardi reported that Ti-doped sodium alanate could be reversibly dehydrogenated under moderate conditions. In this review, the preparative methods; the crystal structure; the physico-chemical and hydrogen absorption-desorption properties of the alanates of Li, Na, K, Ca, Mg, Y, Eu, and Sr; and of some of the most interesting multi-cation alanates will be summarized and discussed. The most promising alanate-based reactive hydride composite (RHC) systems developed in the last few years will also be described and commented on concerning their hydrogen absorption and desorption performanc

Abandonment/Reuse. Some Reflections on the Reactivation Potentiality of Abandoned Heritage in Inner Areas

Il movimento e lo spostamento sono sempre stati una caratteristica della condizione umana. Quando gli eventi naturali costringono all’abbandono, oltre alla distruzione del patrimonio costruito le persone sperimentano lo sradicamento e la perdita di identità. In Calabria, questi fenomeni sono evidenti nella costellazione di “doppi” nati negli ultimi decenni. Una volta trasferiti gli abitanti, i vecchi centri sono lasciati al loro destino di oblio e condanna alla marginalità. Quale possibile futuro per questi luoghi? Il contributo vuole riflettere sul potenziale di riattivazione del patrimonio abbandonato nelle aree interne. Partendo dalla premessa che è impossibile ripopolare tutte le aree marginali, discutere intorno al riuso o abbandono di questi luoghi implica riflettere su diversi livelli. Molti fattori influenzano quello che Mioni ha definito “l’indice di vitalità dei luoghi”, e la loro considerazione è essenziale per comprendere le reali possibilità di rigenerazione. La costruzione di un modello metodologico di valutazione di questa potenzialità, che considera l’apporto di risorse endogene ed esogene, potrebbe essere uno strumento efficace per aiutare i professionisti e le amministrazioni ad indirizzare gli interventi e a orientare correttamente i finanziamenti.Movement and displacement have always been a feature of the human condition. When natural events force abandonment, in addition to the built heritage destruction, people experiment with eradication and loss of identity. In Calabria, these phenomena are evident by the constellation of “doubles” born in the last decades. Once the inhabitants have moved, the old centers are left to their fate of inevitable oblivion and condemnation to marginality. What possible future for these places? The contribution reflects on the reactivation potentiality of abandoned heritage in inner areas. Starting from the premise that it is impossible to repopulate all the marginal areas, questioning the reuse or abandonment of these places implies reflecting on different levels. Many factors influence, as Mioni stated, the “vitality index” of places, and their consideration is essential to understanding the real possibilities of regeneration. The methodological construction of an assessment model of this potentiality, which considers endogenous and exogenous resources, could be an effective tool to help professionals and administrations target the interventions and correctly orient funding

Application of a New Method for GWAS in a Related Case/Control Sample with Known Pedigree Structure: Identification of New Loci for Nephrolithiasis

In contrast to large GWA studies based on thousands of individuals and large meta-analyses combining GWAS results, we analyzed a small case/control sample for uric acid nephrolithiasis. Our cohort of closely related individuals is derived from a small, genetically isolated village in Sardinia, with well-characterized genealogical data linking the extant population up to the 16th century. It is expected that the number of risk alleles involved in complex disorders is smaller in isolated founder populations than in more diverse populations, and the power to detect association with complex traits may be increased when related, homogeneous affected individuals are selected, as they are more likely to be enriched with and share specific risk variants than are unrelated, affected individuals from the general population. When related individuals are included in an association study, correlations among relatives must be accurately taken into account to ensure validity of the results. A recently proposed association method uses an empirical genotypic covariance matrix estimated from genome-screen data to allow for additional population structure and cryptic relatedness that may not be captured by the genealogical data. We apply the method to our data, and we also investigate the properties of the method, as well as other association methods, in our highly inbred population, as previous applications were to outbred samples. The more promising regions identified in our initial study in the genetic isolate were then further investigated in an independent sample collected from the Italian population. Among the loci that showed association in this study, we observed evidence of a possible involvement of the region encompassing the gene LRRC16A, already associated to serum uric acid levels in a large meta-analysis of 14 GWAS, suggesting that this locus might lead a pathway for uric acid metabolism that may be involved in gout as well as in nephrolithiasis

Il Restauro come “traduzione”. Insegnare la disciplina nella classe multiculturale

The term “translate”, from the Latin traducĕre (trans and ducere), refers to the gesture of carrying, transferring something from one side to the other. The ancient Romans used the term vertere to define a particular practice of translating: «[…] A type of translation whose cultural paradigm was constituted by radical mutation and metamorphosis. Translating in the sense of vertere presupposes that the sentence - and often also the person who pronounces it - change the identity to become others» (Bettini 2012, p. XV). These etymological references suggest developing some reflections on the Restoration discipline’s teaching in the multicultural class. Those directly involved in these activities are well aware that they will inevitably be confronted with the "other" and "elsewhere": a rich mix of different origins, educational backgrounds and cultural memories. The contribution intends to reflect on the implications of teaching the discipline in the multicultural classroom, on the difficulties, on the contents, on the communication methods, on the strategies to be implemented for effective teaching and on the intersections between teaching and research. The ability to trigger a rich and constructive debate, but also the role to which we are called as "facilitators" within learning that is not notionism but first of all based on sharing an approach, force us to reflect on a crucial issue: what is the cultural transmission that goes through translation?Il termine tradurre, dal latino traducĕre (trans e ducere), fa riferimento al gesto di trasportare, trasferire qualcosa da una parte all’altra. Gli antichi Romani utilizzavano il termine vertere per definire una pratica particolare del tradurre: «[…] un tipo di traduzione il cui paradigma culturale era costituito dalla mutazione radicale e dalla metamorfosi. Tradurre nel senso di vertere presuppone che l’enunciato – e spesso anche colui che lo pronunzia – mutino la propria identità per diventare altri» (Bettini 2012, p. XV). Queste suggestioni etimologiche forniscono lo spunto per sviluppare alcune riflessioni sull’insegnamento della disciplina del Restauro nella classe multiculturale. Chi è direttamente coinvolto in queste attività ben sa che inevitabilmente sarà messo di fronte all’“altro” e all’“altrove”: una ricca mixité di provenienze e di memorie culturali differenti.Il contributo vuole riflettere sulle implicazioni connesse all’insegnamento della disciplina nella classe multiculturale, sulle difficoltà, sui contenuti, sulle modalità comunicative, sulle strategie da mettere in atto per una didattica efficace e sulle intersezioni tra didattica e ricerca. La capacità di innescare un dibattito ricco e costruttivo, ma anche il ruolo a cui siamo chiamati di “facilitatori” all’interno di un apprendimento prima di tutto basato sulla condivisione di un approccio, ci costringono a riflettere su una questione cruciale: quale trasmissione culturale passa attraverso la traduzione?

“Costruire accoglienza”. Il patrimonio culturale dei centri minori come occasione di rigenerazione urbana e sociale

The progressive depopulation that has affected many small historic centers in last years has triggered heavy repercussions on the landscape, on the built heritage and on the identity of these places. Following the abandonment, the processes of “care” and protection of the territory, which are necessary condition for the conservation and transmission of places, are interrupted: the buildings gradually degrades, the nature reconquers spaces and those that once were vital places are transformed into fragile and vulnerable landscapes. Which strategies can be implemented to reserve this phenomenon? The contribution presents some reflections resulting from the research FARB 2016 developed by the authors at the Department of Architecture and Urban Studies of Politecnico di Milano. “Building hospitality” means on the one hand acting on cultural heritage to enhance the places, protecting the identity elements but at the same time looking at contemporary models and, on the other hand, working on “communities”, to create long lasting economies. The paper wants to give back centrality to the built heritage, starting from the idea that the regeneration process must start precisely from the places, by considering the heritage of the small centers as a dynamic resource that, if properly reactivated, may be able to generate the transformation. “Costruire accoglienza”. Il patrimonio culturale dei centri minori come occasione di rigenerazione urbana e sociale Il progressivo spopolamento che ha interessato molti centri storici minori negli ultimi anni ha innescato pesanti ricadute sul paesaggio, sul patrimonio costruito e sul tessuto identitario di questi luoghi. In seguito all’abbandono si interrompono quei processi di “cura” e presidio del territorio che sono condizione necessaria per la conservazione e trasmissione dei luoghi. Quali strategie si possono mettere in atto per invertire questo fenomeno? Il contributo presenta alcune riflessioni frutto della ricerca FARB 2016 sviluppata dagli autori presso il Dipartimento di Architettura e Studi Urbani del Politecnico di Milano. “Costruire accoglienza” significa da un lato agire sul patrimonio culturale per andare a ri-significare i luoghi, proteggendone le invarianti ma guardando allo stesso tempo a modelli contemporanei e dall’altro lato lavorare sulle “comunità”, per dare vita ad economie di lunga durata. Il contributo vuole ridare centralità al costruito, partendo dalla convinzione che il processo di rigenerazione debba ripartire proprio dai luoghi, considerando il patrimonio dei piccoli centri come una risorsa dinamica che, se opportunamente riattivata, può essere in grado di generare la trasformazione. Il progressivo spopolamento che ha interessato molti centri storici minori negli ultimi anni ha innescato pesanti ricadute sul paesaggio, sul patrimonio costruito e sul tessuto identitario di questi luoghi. In seguito all’abbandono si interrompono quei processi di “cura” e presidio del territorio che sono condizione necessaria per la conservazione e trasmissione dei luoghi. Quali strategie si possono mettere in atto per invertire questo fenomeno? Il contributo presenta alcune riflessioni frutto della ricerca FARB 2016 sviluppata dagli autori presso il Dipartimento di Architettura e Studi Urbani del Politecnico di Milano. “Costruire accoglienza” significa da un lato agire sul patrimonio culturale per andare a ri-significare i luoghi, proteggendone le invarianti ma guardando allo stesso tempo a modelli contemporanei e dall’altro lato lavorare sulle “comunità”, per dare vita ad economie di lunga durata. Il contributo vuole ridare centralità al costruito, partendo dalla convinzione che il processo di rigenerazione debba ripartire proprio dai luoghi, considerando il patrimonio dei piccoli centri come una risorsa dinamica che, se opportunamente riattivata, può essere in grado di generare la trasformazione.  "Building hospitality".  The cultural heritage of small centers as opportunity for urban and social regeneration The progressive depopulation that has affected many small historic centers in last years has triggered heavy repercussions on the landscape, on the built heritage and on the identity of these places. Following the abandonment, the processes of “care” and protection of the territory, which are necessary condition for the conservation and transmission of places, are interrupted: the buildings gradually degrades, the nature reconquers spaces and those that once were vital places are transformed into fragile and vulnerable landscapes. Which strategies can be implemented to reserve this phenomenon? The contribution presents some reflections resulting from the research FARB 2016 developed by the authors at the Department of Architecture and Urban Studies of Politecnico di Milano. “Building hospitality” means on the one hand acting on cultural heritage to enhance the places, protecting the identity elements but at the same time looking at contemporary models and, on the other hand, working on “communities”, to create long lasting economies. The paper wants to give back centrality to the built heritage, starting from the idea that the regeneration process must start precisely from the places, by considering the heritage of the small centers as  dynamic resource that, if properly reactivated, may be able to generate the transformation.