The impact of carbon materials on the hydrogen storage properties of light metal hydrides

The safe and efficient storage of hydrogen is still one of the remaining challenges towards fuel cell powered cars. Metal hydrides are a promising class of materials as they allow the storage of large amounts of hydrogen in a small volume at room temperature and low pressures. However, usually the kinetics of hydrogen release and uptake and the thermodynamic properties do not satisfy the requirements for practical applications. Therefore current research focuses on catalysis and the thermodynamic tailoring of metal hydride systems. Surprisingly, carbon materials used as additive or support are very effective to improve the hydrogen storage properties of metal hydrides allowing fast kinetics and even a change in the thermodynamic properties. Even though the underlying mechanisms are not always well understood, the beneficial effect is probably related to the peculiar structure of the carbon materials. This feature article gives an introduction to the different carbon materials, an overview of the preparation strategies to synthesize carbon/hydride nanocomposites, and highlights the beneficial effect of carbon by discussing two important hydrides: MgH(2) and NaAlH(4)

From Lithium-Ion to Sodium-Ion Batteries

The research is mainly motivated by the abundance of sodium and the larger amount of sodium compounds in comparison with lithium

Збалансування інтересів сторін трудових відносин як засада забезпечення договірного регулювання таких відносин з боку держави

Стаття присвячена вивченню збалансування інтересів сторін трудових відносин не як мети договірного регулювання вказаних відносин, а як орієнтира та базисної засади для держави при розробці нового Трудового кодексу України. Визначається сутність такого принципу та його основна спрямованість. Ключові слова: сторони трудових відносин, регулювання трудових відносин, інтерес, договірне регулювання трудових відносин.Статья посвящена изучению сбалансирования интересов сторон трудовых отношений не как цели договорного регулирования указанных отношений, а как ориентира и базисного основания для государства при разработке нового Трудового кодекса Украины. Определяется сущность такого принципа и его основная направленность. Ключевые слова: стороны трудовых отношений, регулирование трудовых отношений, интерес, договорное регулирование трудовых отношений.The article is devoted to the analysis of balancing interests of labour relations parties as not as the purpose of contractual regulation the mentioned relations but as the guideline and basic priority for state with elaborating the new Labour code of Ukraine. The essence of this principle and its leading direction are determined. Key words: labour contracting parties, the regulation of labour relations, the interest, contractual regulation of labour relations

Towards commercial products by nanocasting : characterization and lithium insertion properties of carbons with a macroporous, interconnected pore structure

Carbon materials with defined porosity are prepared using the nanocasting approach. The structural properties of the prepared carbon materials are examined by SEM, XRD, XPS, elemental analysis, nitrogen physisorption and Hg porosimetry. The materials exhibit an interconnected porous network with spherical pores in the macropore range, being a replica of spherical SiO2 particles. The average macropore size (300-700 nm) and surface area (35-470 m2 g-1) can be tailored by the choice of template and carbon precursor. More importantly, based on silica templates prepared by flame pyrolysis, the whole process, including HF etching of the template, can be easily industrialized. Lithium storage measurements are used to demonstrate the beneficial transport properties of the porous carbon materials which are referenced against non-porous carbons. The porous carbon materials exhibit high capacity (550 mA h g-1 at C/5) and excellent rate capability (90 mA h g-1 at 60C). Surprisingly, the excellent lithium storage properties are related to the macroporous framework rather than high surface area and/or micro- and mesoporosity