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991.
David G Calatayud Teresa Jardiel Marco Peiteado Amador C Caballero Daniel Fernández-Hevia 《Nanoscale research letters》2014,9(1):273
The fabrication of hierarchical anatase microspheres with potential photocatalytic properties eventually comprises a consolidation step in which a high degree of crystalline order is typically achieved through conventional electric heating treatments. This however entails a substantial reduction in the specific surface area and porosity of the powders, with the consequent deterioration in their photocatalytic response. Here, we have tested the employ of microwave heating as an alternative energy-saving sintering method to promote fast crystallization. The results obtained suggest that under the microwave radiation, the TiO2 hierarchical structures can effectively crystallize in a drastically reduced heating time, allowing the specific surface area and the porosity to be kept in the high values required for an improved photocatalytic performance. 相似文献
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Dr. Camille Decroocq Dr. Antoine Joosten Raphaël Sergent Teresa Mena Barragán Prof. Carmen Ortiz Mellet Prof. Philippe Compain 《Chembiochem : a European journal of chemical biology》2013,14(15):2038-2049
In view of recent reports of a strong multivalent effect in glycosidase inhibition, a library of β‐CD‐based multivalent iminosugars has been efficiently synthesized by way of CuI‐catalyzed azide–alkyne cycloaddition (CuAAC). In combination with the first application of isothermal titration calorimetry (ITC) experiments to the study of multivalent iminosugar–enzyme interactions, the inhibition properties of these click clusters were evaluated on a panel of glycosidases. The structural parameters that were varied include valency, peripheral ligand structure, and topology. The inhibition results obtained with the iminosugar clusters further highlight the importance of multivalency in the inhibition of α‐mannosidase. Generally, the evaluated multivalent iminosugars displayed comparable thermodynamic signatures of binding towards α‐mannosidase (Jack bean): that is, large negative enthalpies of complexation coupled with small entropies of either sign. In addition, the enthalpy–entropy compensation observed in all tested cases may be attributed to a common mechanism of dissociation for the enzyme–multivalent iminosugar interactions. The measured binding stoichiometries indicated that each iminosugar cluster interacts with no more than one protein molecule. 相似文献
996.
The synthesis and characterization of copper-based metal–organic framework/graphite oxide composites
New composites of a copper-based metal–organic framework and graphite oxide were synthesized with different ratios of HKUST-1 (also called MOF-199) and graphite oxide. These compounds, as well as the parent materials, were characterized by X-ray diffraction, sorption of nitrogen, FT-IR spectroscopy, thermal analyses, scanning electron microscopy, and sorption of hydrogen. The composites exhibit features similar to HKUST-1 as well as an increased porosity compared to the parent materials. The formation of new small pores is demonstrated by an increase in the hydrogen uptake. The results suggest that the building process of the composites occurs via the reaction/binding of the copper dimers from the HKUST-1 with/to the functional groups in graphite oxide (epoxy, carboxylic, hydroxylic, sulfonic). 相似文献
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