Supported metals are traditionally prepared by impregnating a support material with the metal precursor solution, followed by reduction in hydrogen at elevated temperatures. In this study, a polymeric support has been considered. Polypyrrole (PPy) has been chemically synthesized using FeCl 3 as a doping agent, and it has been impregnated with a H 2 PtCl 6 solution to prepare a catalyst precursor. The restricted thermal stability of polypyrrole does not allow using the traditional reduction in hydrogen at elevated temperature, and chemical reduction under mild conditions using sodium borohydride implies environmental concerns. Therefore, cold RF plasma has been considered an environmentally friendly alternative.Ar plasma leads to a more effective reduction of platinum ions in the chloroplatinic complex anchored onto the polypyrrole chain after impregnation than reduction with sodium borohydride, as has been evidenced by XPS. The increase of RF power enhanced the effectiveness of the Ar plasma treatment.A homogeneous distribution of platinum nanoparticles has been observed by TEM after the reduction treatment with plasma. The Pt/polypyrrol catalyst reduced by Ar plasma at 200 watts effectively catalyzed the aqueous reduction of nitrates with H 2 to yield N 2 , with a very low selectivity to undesired nitrites and ammonium by-products. † Electronic supplementary information (ESI) available. See

Purpose – The aims of this paper are: to identify the dimensions of knowledge management (KM), and to propose a model for KM that will be useful for future researchers in carrying out KM measurement. Design/methodology/approach – The paper is based on a literature review of theoretical and empirical contributions to KM. Findings – The results obtained show that the creation, transfer and storage, and implementation and use are dimensions of the concept of KM. On the basis of these dimensions, this study proposes a model integrating these dimensions and operationalizes it using selected items, so that future researchers may carry out measurements using the proposed model. Practical implications – The study implies that companies and researchers use a smaller time in theoretical checks and can devote to measurements which develop improvements. Originality/value – The present model differs from other, previous models in that it integrates various approaches to the study of KM.

[1] Mean sea level observations from an historical tide gauge located in Cadiz (Southern Spain) spanning the period 1880-1924 were recovered from national archives. Daily sea level averages stored in handwritten log books were digitized, quality controlled, and referred to the same benchmark. A careful analysis of all the high precision leveling surveys available in the area of the tide gauge enabled the establishment of a common datum with a modern record starting in 1961 from another tide gauge located only 2.5 km apart, with accuracy better than 5 mm. As a result, a consistent daily mean sea level record from 1880 to 2009 was constructed. The 20th century relative mean sea level rise in Cadiz is 0.7 AE 0.1 mm yr À1, which becomes 1.0 AE 0.2 mm yr À1 once corrected for vertical land movement with high precision GPS data, in agreement with nearby records. The analysis of the seasonal sea level cycle indicated that the amplitude of the annual cycle has increased during the 20th century. This work evidences the significance of sea level data rescue for present-day climate research.

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Pt and Pt/Sn catalysts supported on polypyrrole (PPy) have been prepared using Ar plasma to reduce the metal precursors dispersed on the polymer. The PPy support was synthesized by chemical polymerization of pyrrole with FeCl 3 $6H 2 O, this leading to the conducting form of the polymer (conductimetric measurements). The Ar plasma treatment produced a partial reduction of platinum ions, anchored as platinum chloro-complexes to the PPy chain, into metallic platinum. A homogeneous distribution of Pt and Sn nanoparticles was observed by TEM. Activity of the PPy-supported catalysts was evaluated in the reduction of aqueous nitrate with H 2 at room temperature. Nitrate concentration in water below the maximum acceptable level of 50 mg L À1 was achieved with all catalysts. However, considering not only efficiency in nitrate reduction, but also minimized concentrations of undesired nitrite and ammonium, the monometallic Pt catalyst seems to be the most promising one.