Synthesis, Infra-red, Raman, NMR and structural characterization by X-ray Diffraction of [C12H17N2]2CdCl4 and [C6H10N2]2Cd3Cl10 compounds

The synthesis, infra-red, Raman and NMR spectra and crystal structure of 2, 4, 4- trimethyl-4, 5- dihydro-3H-benzo[b] [1, 4] diazepin-1-ium tetrachlorocadmate, [C12H17N2]2CdCl4 and benzene-1,2-diaminium decachlorotricadmate(II) [C6H10N2]2Cd3Cl10 are reported. The [C12H17N2]2CdCl4 compound crystallizes in the triclinic system (P-1 space group) with Z = 2 and the following unit cell dimensions: a = 9.6653(8) angstrom, b = 9.9081(9) angstrom, c = 15.3737(2) angstrom, alpha = 79.486(1)degrees, beta = 88.610(8)degrees and gamma = 77.550(7)degrees. The structure was solved by using 4439 independent reflections down to R value of 0.029. In crystal structure, the tetrachlorocadmiate anion is connected to two organic cations through N-H...Cl hydrogen bonds and Van Der Waals interaction as to build cation-anion-cation cohesion. The [C6H10N2]2Cd3Cl10 crystallizes in the triclinic system (P-1 space group). The unit cell dimensions are a = 6.826 (5)angstrom, b = 9.861 (7)angstrom, c = 10.344 (3)angstrom, alpha = 103.50 (1)degrees, beta = 96.34 (4)degrees and gamma = 109.45 (3)degrees, Z=2. The final R value is 0.053 (Rw=0.128). Its crystal structure consists of organic cations and polymeric chains of [Cd3Cl10]4- anions running along the [011] direction, In The [C6H10N2]2Cd3Cl10 compounds hydrogen bond interactions between the inorganic chains and the organic cations, contribute to the crystal packing. PACS Codes: 61.10.Nz, 61.18.Fs, 78.30.-jComment: 19 pages, 10 figure

Caractéristiques des réactions endothermiques d'interface. Recherche des états thermodynamiques d'interface en relation avec les écarts à l'équilibre t. 292, pp. 49 52.

International audienceL'endothermicité de la vaporisation peut donner des propriétés particulières à l'interface. L'exploration de la carte thermique du système associée à un modèle permet d'accéder aux profils thermiques dans chaque phase et d'établir les températures à l'interface; ses différents états thermodynamiques sont en relation avec l'écart à l'équilibre du système : équilibre interfacial près de l'équilibre, puis apparition d'une discontinuité de température, enfin déséquilibre de température et de potentiel chimique

Étude thermodynamique du polymère super absorbant X10 vis–à–vis de l’eau vapeur

The organic polymers super absorbents present values of specific surface lower than 2m2/g. The isobars of adsorption of water vapor on studied polymer are of type III at ambient temperature with the hysterisis phenomena. For temperatures lower than ambient, the isobars become deformed because of an effect of chains. This type of polymer is characterized by a multi-layer adsorption which occurs before the full-course one is complete. During reactions of adsorption, the polymer undergoes rearrangement polymeric network which results from a co-operative diffusion of the water molecules and from a spacing of chain followed by an expansion of the polymeric network. Three types of water molecules adsorbed on polymer were identified: strongly dependent water, adsorbed water and the water only trapped between the macromolecular chains

Caractéristiques des réactions endothermiques d'interface: lois d'évolution en relation avec les états thermodynamiques d'interface

Note de Cinétique-transmise par Adolphe Pacault.-C.R. Acad. SC. Paris, t.292 (16 février 1981). Remise le 5janvier 1981, acceptée le 9 février 1981.International audienceThe knowledge of the different thermodynamic states of an evaporative interface leads us to propose a formulation of the evolution laws (evaporation rate vs pressure) adapted to each regime (interfacial equilibrium or non equilibrium). Starting from fluid dynamics and irreversible thermodynamics, the model is able to determine the interface flux-forces relations which express the transport coefficients and the thermodynamic coupling effects. The theoretical results are compared to experimental data relative to water evaporation al T =313 K. Taking into account the different regimes arising for the deviation from equilibrium, the model reproduces quantitatively the experimental kinetic curves for precise values of the phenomenological coefficients. These coefficients deduced from the experiments verify all the thermodynamic theoretically established relations.Caractéristiques des réactions endothermiques d'interface : lois d'évolution en relation arec les états thermodynamiques d'interface 1 Gilles Bertrand, Michel Lallemant, Ahdelkader Mokhlisse et Roger Prud'homme La connaissance des différents états thermodynamiques d'une interface évaporative conduit à proposer une formulation des lois d'évolution (vitesse d'évaporation en fonction de la pression) adaptée à chaque régime(équilibre ou déséquilibre interfacial). Ces prévisions théoriques sont confrontées aux données expérimentales relatives à l'évaporation de l'eau â Te=313 K

The adsorption of water vapor on super absorbent product at low temperatures and low mass.

The adsorption isotherms of water vapor on super absorbent product have the same form of type III isotherm at ambient temperature with the hysteresis phenomena. For temperatures lower than ambient, the isotherms become deformed because of the chains effect. The polymer is characterized by a multilayer adsorption, which occurs before a full-course is complete. During adsorption reactions, the polymer undergoes rearrangement polymeric network, which results from a cooperative diffusion of the water molecules and from a chain spacing followed by an expansion of the polymeric network. Three types of water molecules adsorbed on polymer were identified: strongly dependent water, adsorbed water, and the water only trapped between the macromolecular chains

Étude Thermodynamique Du Polymère Super Absorbant X10 Vis-à-vis De L\u27eau Vapeur

The organic polymers super absorbents present values of specific surface lower than 2m 2/g. The isobars of adsorption of water vapor on studied polymer are of type III at ambient temperature with the hysterisis phenomena. For temperatures lower than ambient, the isobars become deformed because of an effect of chains. This type of polymer is characterized by a multi-layer adsorption which occurs before the full-course one is complete. During reactions of adsorption, the polymer undergoes rearrangement polymeric network which results from a co-operative diffusion of the water molecules and from a spacing of chain followed by an expansion of the polymeric network. Three types of water molecules adsorbed on polymer were identified: strongly dependent water, adsorbed water and the water only trapped between the macromolecular chains. © EDP Sciences

Diagramme polythermique du système H2_2O-(NH4_4)2_2HPO4_4-(NH4_4)2_2SO4_4

The polythermal diagram of the ternary system H$_2$O-(NH$_4$)$_2$HPO$_4$-(NH$_4$)$_2$SO$_4$ has been completed with two isotherms obtained at –15°C and 40°C by conductimetric analysis.One eutectic and one transitional transformation have been observed at –26°C and 6°C respectively