(Z)-2-(4-Nitro­benzyl­idene)-1-benzofuran-3(2H)-one

In the crystal structure of the title compound, C15H9NO4, weak C—H⋯O inter­actions generate rings with R 2 2(8) motifs. The supra­molecular aggregation is completed by the presence of C—H⋯O and van der Waals inter­actions

(Z)-2-(2-Hy­droxy-4-meth­oxy­benzyl­idene)-1-benzofuran-3(2H)-one

In the title compound, C16H12O4, the 1-benzofuran­one unit is in a planar conformation [C—C—C—C = 179.69 (12)°]. The conformation around the C=C double bond [1.3370 (17) Å] is Z. In the crystal, the mol­ecules are stabilized by O—H⋯O (running parallel to the bc plane) and C—H⋯O hydrogen bonds

High Proton Conductivity in a Flexible, Cross-Linked, Ultramicroporous Magnesium Tetraphosphonate Hybrid Framework

Multifunctional materials, especially those combining two or more properties of interest, are attracting immense attention due to their potential applications. MOFs, metal organic frameworks, can be regarded as multifunctional materials if they show another useful property in addition to the adsorption behavior. Here, we report a new multifunctional light hybrid, MgH6ODTMP·2H2O(DMF)0.5 (1), which has been synthesized using the tetraphosphonic acid H8ODTMP, octamethylenediamine-N,N,N′,N′-tetrakis(methylenephosphonic acid), by highthroughput methodology. Its crystal structure, solved by Patterson-function direct methods from synchrotron powder Xray diffraction, was characterized by a 3D pillared open framework containing cross-linked 1D channels filled with water and DMF. Upon H2O and DMF removal and subsequent rehydration, MgH6ODTMP·2H2O (2) and MgH6ODTMP·6H2O (3) can be formed. These processes take place through crystalline−quasi-amorphous−crystalline transformations, during which the integrity of the framework is maintained. A water adsorption study, at constant temperature, showed that this magnesium tetraphosphonate hybrid reversibly equilibrates its lattice water content as a function of the water partial pressure. Combination of the structural study and gas adsorption characterization (N2, CO2, and CH4) indicates an ultramicroporous framework. High-pressure CO2 adsorption data are also reported. Finally, impedance data indicates that 3 has high proton conductivity σ = 1.6 × 10−3 S cm−1 at T = 292 K at ∼100% relative humidity with an activation energy of 0.31 eV.Proyecto nacional MAT2010-15175 (MICINN, España

Les alios humiques des podzols tropicaux du Congo : constituants, microet ultra-structure

Les podzols développés sur sables Batéké sont caractérisés par d'épais horizons spodiques indurés en alios qui accumulent d'importantes quantités de substances humiques à C/N élévé. Dans cet article les auteurs présentent les caractéristiques chimiques et physiques d'un profil situé à Gangolingalo (région de Brazzaville); la matière organique est, dans l'ensemble des horizons spodiques, monomorphe, elle tapisse les grains du squelette et comble les pores. Les traits ultra-structuraux observés au microscope électronique à balayage ou à transmission différencient deux horizons B22h et B23