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Lithium tetrahydridoboranate (LiBH 4 ) may be a potentially interesting material for hydrogen storage, but in order to absorb and desorb hydrogen routinely and reversibly, the kinetics and thermodynamics need to be improved significantly. A priori, this material has one of the highest theoretical gravimetric hydrogen contents, 18.5 wt %, but unfortunately for practical applications, hydrogen release occurs at too high temperature in a non-reversible way. By means of in situ synchrotron radiation powder X-ray diffraction (SR-PXD), the interaction between LiBH 4 and different additivessSiO 2 , TiCl 3 , LiCl, and Ausis investigated. It is found that silicon dioxide reacts with molten LiBH 4 and forms Li 2 SiO 3 or Li 4 SiO 4 at relatively low amounts of SiO 2 , e.g., with 5.0 and 9.9 mol % SiO 2 in LiBH 4 , whereas, for higher amounts of SiO 2 (e.g., 25.5 mol %), only the Li 2 SiO 3 phase is observed. Furthermore, we demonstrate that a solid-state reaction occurs between LiBH 4 and TiCl 3 to form LiCl at room temperature. At elevated temperatures, more LiCl is formed simultaneously with a decrease in the diffracted intensity from TiCl 3 . Lithium chloride shows some solubility in solid LiBH 4 at T > 100°C. This is the first report of substituents that accommodate the structure of LiBH 4 by a solid/solid dissolution reaction. Gold is found to react with molten LiBH 4 forming a Li-Au alloy with CuAu 3 -type structure. These studies demonstrate that molten LiBH 4 has a high reactivity, and finding a catalyst for this H-rich system may be a challenge.

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Kosovo 1 har siden juni 1999 vaeret et internationalt protektorat. Den 10. juni 1999 vedtog FN's sikkerhedsråd således en resolution, der midlertidigt tilsidesatte Jugoslaviens suveraenitet og overdrog administrationen af Kosovo til en FN-styret provisorisk administration. Kosovo befinder sig derfor i øjeblikket mellem selvstaendighed og integration i en eksisterende stat, og territoriet kan på denne baggrund betegnes som en kvasistat. Inden Kosovo opnåede den nuvaerende status af protektorat, har befolkningen i territoriet levet som en mere eller mindre undertrykt minoritet. Denne artikel analyserer baggrunden for Kosovos status som protektorat og kvasistat og diskuterer, hvilke problemer og muligheder der er for områdets fremtidige status. KvasistaterStaten opfattes saedvanligvis som den primaere enhed i det internationale samfund (Jackson 2000: 130). Det vaesentligste karakteristikum ved en stat er suveraenitet. En internationalt anerkendt stat besidder suveraenitet, dels med hensyn til interne forhold såsom ret til suveraent at bestemme over territoriet og folket, dels eksternt Kosovo: Fra undertrykt provins