Aqueous dispersions of silane-functionalized laponite clay platelets. A first step towards the elaboration of water-based polymer/clay nanocomposites

International audienc

Possible evidence of the nickel nitrate salt Ni(NO3_3)2_2 . 5.5 H2_2O

In the present work we have focus our care on the controversial intermediate salt : Ni(NO$_3$)$_2$. 5.5H$_2$O To prepare this phase, we have carried out, in the range 60-80°C, a controlled evaporation of a solution of nickel nitrate, hexahydrate resulting from the melting of a 100g Ni(NO$_3$)$_2$. 6H$_2$O batch sample in an isothermal pilot reactor. The proof of its existence is given, for the first time, by powder x-ray diffraction data

STRUCTURAL EFFECTS IN THE ELECTROLYTES GLASS (LiC1) xH2O AND THE NUCLEATION OF METASTABLE PHASES

L'intérêt des électrolytes aqueux pour la compréhension de l'état vitreux est montré par la diffusion ou la diffraction de neutrons et par D.S.C. Sur deux gammes de compositions, le verre formé ne cristallise pas et un verre avec deux Tg différentes est obtenu. L'effet endothermique observé par D.S.C. pendant Tg, est attribué à un réarrangement du verre. L'effet thermique, se produisant dans le liquide très au-dessus de Tg, est probablement dû au réarrangement des molécules d'eau.The interest of aqueous electrolytes for the understanding of the glassy state is shown by neutron scattering or neutron diffraction and Differential Scanning Calorimetry (D.S.C.). In two ranges of composition the formed glass does not crystallize, and a glass with two different Tg is shown. The overshot as observed by D.S.C. during Tg is attributed to a reordering of the glass. The thermal effect occuring in the liquid well above Tg is probably due to a rearrangement of the water molecules

Thermal characteristics of crude oils treated with rheology modifiers

Thermal characteristics of eight crude oils and their treatment with additives were studied by differential scanning calorimetry (DSC), thermomicroscopy, viscometer and pour point tester. Different additives were found as more effective for different type of crude oils depending on the wax content. Crude oils showed a reduced pour point after treatment with additives. Effects of different additives were also discussed by analysing the DSC curves and thermomicroscopy result