Sorption equilibria of CO2 on silica-gels in the presence of water

The sorption equilibria of carbon dioxide on three types of silica gel (SG) with different pore size distributions in the presence of water were studied experimentally using a volumetric method at 275?K with pressures from 0 to 3.7?MPa. Both the pore size distribution of the silica gel and the quantity of pre-sorbed water impact the formation of the CO₂ hydrates. For wet silicon gel A(SG-A) with water loading ratio of 0.75, the highest CO₂ sorption was about 2.5?mmol of CO₂ per gram of dry sorbent at 275?K. Similarly, the highest sorption was about 2.7?mmol for wet SG-B with R _w =0.81. However, CO₂ hydrate did not form on the wet surface of SG-C due to its large pore sizes.     

New heterogeneous catalytic systems based on highly porous ceramic materials modified with immobilized d-metal cage complexes for H2 production from CH4

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Accurate evaluation of the 1s wave functions of kaonic hydrogen

Kaonic hydrogen is studied with realistic potentials in an accurate numerical approach based on Sturmian functions. It is found that the ground-state wave function of the exotic atom with realistic strong interactions is considerably different from the hydrogen-like ones at small distances. The K ^???p scattering length extracted from the 1s energy shift of the kaonic hydrogen by applying the Deser-Trueman formula is severely inconsistent with the one derived directly by solving the Schödinger equation. We pay special attention to the recent measurement of the energy shift and decay width of the 1s kaonic hydrogen state by the DEAR Collaboration. Our work strongly supports the argument that the DEAR data of the K ^???p scattering length extracted with the Deser-Trueman formula from the measured 1s energy shift and decay width are not accurate, if not to say, unreliable.     

Three coordination polymers of 5-aminoisophthalic acid with similar benzimidazole derivative ligands: synthesis,structure and DNA-binding studies

Three novel coordination polymers, [Co(NH₂-Aip)(H₂Bibim)] _n (1), [Co(NH₂-Aip)(HBibimop)] _n  √ nH₂O (2) and [Mn(NH₂-Aip) √ H₂O] _n  √ 2nH₂O (3) with NH₂-Aip and similar benzimidazole derivative ligands (NH₂-Aip = 5-aminoisophthalic acid, H₂Bibim = 2,2′-bibenzimidazole and HBibimop = 1,3-bis(benzimidazol-2-yl)-2-oxapropane), have been synthesised under hydrothermal conditions and structurally characterised by single-crystal X-ray diffraction analysis, elemental analysis and IR spectroscopy. 5-Aminoisophthalic acid ligand adopts μ₂-, μ₃- and μ₄-bridge coordination fashion and benzimidazole derivatives exist as terminal- and bridge-mode in complexes 1–3. The intricate hydrogen bonds and π–π stacking interactions in supramolecular framework are discussed. Using the combination of ultraviolet–visible absorption titration and fluorescence spectra, the experimental results show that complexes 1 and 2 bind to DNA in an intercalative mode and their DNA-binding constants (K _b ) are also found.     

Effective synthesis of benzyl halides triggered by in situ prepared hypervalent halides

An effective approach for the direct benzylhalogenation with in situ generation of hypervalent halides has been developed.A variety of benzyl halides are produced in moderate to excellent yields(up to 99%) with high regioselectivities.UV absorption spectrum is employed to detect the formation of ferr-butyl hypoiodite.