Metal-Substituted Microporous Aluminophosphates

This chapter aims to present the zeotypes aluminophosphates (AlPOs) as a complementary alternative to zeolites in the isomorphic incorporation of metal ions within all-inorganic microporous frameworks as well as to discuss didactically the catalytic consequences derived from the distinctive features of both frameworks. It does not intend to be a compilation of either all or the most significant publications involving metal-substituted microporous aluminophosphates. Families of AlPOs and zeolites, which include metal ion-substituted variants, are the dominant microporous materials. Both these systems are widely used as catalysts, in particular through aliovalent metal ions substitution. Here, some general description of the synthesis procedures and characterization techniques of the MeAPOs (metal-contained aluminophosphates) is given along with catalytic properties. Next, some illustrative examples of the catalytic possibilities of MeAPOs as catalysts in the transformation of the organic molecules are given. The oxidation of the hardly activated hydrocarbons has probably been the most successful use of AlPOs doped with the divalent transition metal ions Co2+, Mn2+, and Fe2+, whose incorporation in zeolites is disfavoured. The catalytic role of these MeAPOs is rationalized based on the knowledge acquired from a combination of the most advanced characterization techniques. Finally, the importance of the high specificity of the structure-directing agents employed in the preparation of MeAPOs is discussed taking N,N-methyldicyclohexylamine in the synthesis of AFI-structured materials as a driving force. It is shown how such a high specificity could be predicted and how it can open great possibilities in the control of parameters as critical in catalysis as crystal size, inter-and intracrystalline mesoporosity, acidity, redox properties, incorporation of a great variety of heteroatom ions or final environment of the metal site (surrounding it by either P or Al)

Legal Technologies of Primitive Accumulation: Judicial Robbery and Dispossession‐by‐Restitution in Warsaw

© 2019 Urban Research Publications Limited Among the ‘extra-economic means’ that facilitate primitive accumulation, or accumulation by dispossession, the law plays a prominent role. But works on neoliberal urban restructuring rarely engage with concrete legal technologies. Analysing judicial property restitution (‘reprivatization’) in Warsaw, this article grasps the machine of accumulation by dispossession at a moment of faltering and exposes the distinctive legal technologies behind its troubleshooting. It makes three contributions to critical urban studies. First, it demonstrates how judicial systems can steal political conflicts that obstruct the cycle of accumulation by dispossession. It thus introduces the notion of ‘judicial robbery’, a non-legislated expropriation of common property through judicial engineering that simultaneously deprives the public of political agency. Second, it shows that seemingly neutral legal technicalities, usually sheltered from political debate, can become a key locus of urban politics. Third, it examines the agency, scope and spatial patterns of ‘dispossession by restitution’, the term I use for a locally specific form of accumulation by dispossession in Warsaw. Lastly, I raise the question of political struggle against primitive accumulation. Is the judicial robbery reversible? If we can reclaim property, can we also reclaim political conflicts that have been stolen by the law?

Self-assembled nanoreactors

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