Efficient synthesis of alkali borohydrides from mechanochemical reduction of borates using magnesium-aluminum-basedwaste

Lithium borohydride (LiBH4) and sodium borohydride (NaBH4) were synthesized via mechanical milling of LiBO2, and NaBO2 with Mg-Al-based waste under controlled gaseous atmosphere conditions. Following this approach, the results herein presented indicate that LiBH4 and NaBH4 can be formed with a high conversion yield starting from the anhydrous borates under 70 bar H2. Interestingly, NaBH4 can also be obtained with a high conversion yield by milling NaBO2·4H2O and Mg-Al-based waste under an argon atmosphere. Under optimized molar ratios of the starting materials and milling parameters, NaBH4 and LiBH4 were obtained with conversion ratios higher than 99.5%. Based on the collected experimental results, the influence of the milling energy and the correlation with the final yields were also discussed.Fil: Le, Thi Thu. Helmholtz Zentrum Geesthacht GmbH. Institute of Materials Research, Materials Technology; AlemaniaFil: Pistidda, Claudio. Helmholtz Zentrum Geesthacht GmbH. Institute of Materials Research, Materials Technology; AlemaniaFil: Puszkiel, Julián Atilio. Helmholtz Zentrum Geesthacht GmbH. Institute of Materials Research, Materials Technology; Alemania. Comisión Nacional de Energía Atómica. Centro Atómico Bariloche; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Milanese, Chiara. Universita Degli Studi Di Pavia; ItaliaFil: Garroni, Sebastiano. University of Sassari; ItaliaFil: Emmler, Thomas. Helmholtz Zentrum Geesthacht GmbH. Institute of Materials Research, Materials Technology; AlemaniaFil: Capurso, Giovanni. Helmholtz Zentrum Geesthacht GmbH. Institute of Materials Research, Materials Technology; AlemaniaFil: Gizer, Gökhan. Helmholtz Zentrum Geesthacht GmbH. Institute of Materials Research, Materials Technology; AlemaniaFil: Klassen, Thomas. Helmholtz Zentrum Geesthacht GmbH. Institute of Materials Research, Materials Technology; Alemania. Helmut Schmidt University; Alemania. University of the Federal Armed Forces Hamburg; AlemaniaFil: Dornheim, Martin. Helmholtz Zentrum Geesthacht GmbH. Institute of Materials Research, Materials Technology; Alemani

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

Using intermolecular interactions to crosslink PIM-1 and modify its gas sorption properties

The intermolecular interactions between the “polymer of intrinsic microporosity” PIM-1 and polycyclic aromatic hydrocarbons (PAHs) have been investigated with the aim of modifying the gas sorption and physical properties. Mixing PIM-1 with selected PAHs resulted in rapid precipitation of polymer. Blending PIM-1 with pyrene had a significant effect of the gas sorption properties of the resulting films; dramatically reduced N2 uptake (77 K), whilst CO2 uptake at 298 K was only slightly reduced. A gate-opening behaviour was also observed for the N2 gas sorption (77 K), which was related to the pyrene content of the blend. Using an electron-donating PAH as the additive resulted in a stronger interaction. By exploiting a post-modification strategy after PIM-1 film formation, the absorption of either pyrene or 1-aminopyrene produced films with higher elastic moduli and greatly improved CO2/N2 gas sorption selectivities (293 K). Single gas permeability measurements revealed that while the 1-aminopyrene modified film possessed reduced CO2 permeability, it possessed enhanced CO2/N2 selectivity. Importantly, the ageing of the permeability was halted over the 50 days tested, likely due to the physical crosslinking of the polymer chains by 1-aminopyrene

Neugestaltung des Ostaueparks Karlsruhe

Bei der Planung des Ostaueparks, habe ich versucht den Park so zu gestalten, dasser vielfältig nutzbar ist, und für alle Bevölkerungsgruppen etwas zu bieten hat.Besonderes Augenmerk habe ich auch auf die Durchführbarkeit der baulichenAnlagen gelegt und deshalb weitgehend auf Einrichtungen verzichtet, von denen ichnicht sicher war ob sie ausführbar sind.Bei der Modellierung des Geländes habe ich darauf geachtet, dass sich Aushub desSees und Aufschüttung der Hügel weitgehend die Waage hält.Die Entwurfsgestaltung soll einen Eindruck des Parks vermitteln können und auch fürLaien gut nachvollziehbar sein. Deswegen habe ich mich für Perspektivenentschieden, die sehr zeitintensiv sind, und auf technische Zeichnungen verzichtet.Ich hoffe dieser Entwurf kann einen Anstoß zur Gestaltung des Parks geben, da er inseiner jetzigen Form kaum angenommen wird, trotz der eigentlich guten Lage undreizvollen Kulisse

Plasmon-Mediated Embedding of Nanoparticles in a Polymer Matrix: Nanocomposites Patterning, Writing, and Defect Healing

Plasmonics, as an emerging field, aims to exploit the unique optical properties of metallic nanostructures to enable routing and active manipulation of light on the nanoscale. Plasmonic heating is a phenomenon, which is recently recognized for its potential in photothermal therapy. Here we show the first proof-of-concept experiment based on plasmonic heating for selective and precise embedding of nanoparticles in a polymeric matrix. We demonstrate a unique way for in situ fabrication of nanocomposites in different forms including patterning, writing, and defect healing in a controlled manner along with crystallinity control through light irradiation