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51.
Elhamzaoui H Jousseaume B Riague H Toupance T Dieudonné P Zakri C Maugey M Allouchi H 《Journal of the American Chemical Society》2004,126(26):8130-8131
Hybrid materials where layers of tin oxide alternate with layers of hydrophobic organic chains were prepared by the hydrolysis of distannylated compounds containing an organic chain alpha,omega-disubstituted by tripropynylstannyl groups. In the case of an aliphatic chain, hydrolysis under microemulsion conditions led to the organization of the corresponding hybrid. These hydrolysis conditions also induced a high surface area and a defined mesoporosity in the hybrid. When a mixed aromatic-aliphatic spacer was used, weak hydrophobic interactions between the spacers were sufficient to generate the same type of organization in the corresponding material. 相似文献
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Sihem Boufas Hocine Merazig Lamia Bendjeddou Georges Dns Adel Beghidja Anna Grazia Moliterni 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(1):i7-i9
Mg2Ru2Cl10O·16H2O {dimagnesium μ‐oxo‐bis[pentachlororuthenate(IV)] hexadecahydrate} crystallizes in the monoclinic system (space group P21/c). The structure consists of layers of [Ru2Cl10O]4− anions, [Mg(H2O)6]2+ cations and water molecules stacked along the a axis. Only the O atom bonded to Ru occupies the 2a site with symmetry. All the other atoms occupy general 4e sites. The crystal structure is stabilized by O—H⋯O and O—H⋯Cl interactions. 相似文献
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The phase diagrams of binary mixtures formed by 1-ethyl-3-methylimidazolium hexafluorophosphate ([emim][PF6]) and 2-phenylimidazole or 4,5-diphenylimidazole or 2,4,5-triphenylimidazole has been established using differential scanning calorimetry. Solutions containing 2,4,5-triphenylimidazole display phase splitting at high temperature range. 相似文献
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A. Hamdi M. Naït Abdelaziz N. Aït Hocine P. Heuillet N. Benseddiq 《Polymer Testing》2006,25(8):994-1005
In this work, we attempt to derive a fracture criterion for filled and unfilled elastomer vulcanizates and thermoplastics from a set of experimental data. Firstly, fracture criteria reported in the literature have been applied to experimental data obtained from tests including various loading modes (simple tension, equal biaxial tension and biaxial tension) and performed on four materials: a natural rubber (NR), a styrene butadiene rubber (SBR), a polyurethane (PU) and a thermoplastic elastomer (TPE).
Then, a new failure criterion based on an equivalent elongation concept is proposed. This equivalent elongation seems to be linearly dependent on a given biaxiality ratio n=(ln(λ2b)/ln(λ1b)), which leads to expressing the principal elongations at break as functions of both the biaxiality n and two experimental parameters. Quite good agreement is highlighted when comparing the failure experimental data with the proposed criterion for the tested elastomers. 相似文献
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The mechanical properties of polyamide-12/Cloisite 30B (PA12/C30B) nanocomposites prepared by melt compounding were studied as a function of clay volume fraction φ under various processing conditions. All measured mechanical characteristics, Young's modulus, yield stress, strain at break and stress at break, exhibit a transition at φp1%, identified with a percolation threshold. Also, the linear and non-linear mechanical properties appeared to depend on the degree of exfoliation of the structure, which can be tuned by the processing conditions. The three-phase Ji's theoretical model was used to predict Young's modulus as a function of clay concentration, focusing on the influence of the degree of exfoliation. Experimental yield stress data were fitted to Pukanszky's model and discussed in terms of PA12/C30B interfacial adhesion. 相似文献
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Spray cooling of heated surfaces is common in many industrial applications, notably steelmaking, because of its high heat
dissipating ability. Control of the surface heat flux rate contributes to better products; it is shown that the heat transfer
rate depends on the mass fraction of liquid. Quantitative information regarding the parameters affecting spray cooling is
relatively scarce. The rate of heat transfer from a plate due to impinging of an array of water jets was investigated numerically
through the solution of heat conduction equation. The simulation is carried out for eight different sprayers, in the range
of ejected fluid pressure between 1 bar and 3 bars. Experimental data are used to study the influence of the function g(x, y), of dispersed water, on heat transfer variations across the surface at the temperature of 600°C. Curves were generated showing
time histories of the steel temperature for the removal of high heat fluxes of the order of 300 W/cm2. It was also observed that for lower temperatures, the predicted local heat transfer coefficient increased significantly.
In memory of H. Mzad’s father Mebrouk. 相似文献
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