With the aim of providing reliable benchmark values, we have measured the Soret, thermodiffusion and molecular diffusion coefficients for the ternary mixture formed by 1,2,3,4-tetrahydronaphthalene, isobutylbenzene and n-dodecane for a mass fraction of 0.8-0.1-0.1 and at a temperature of 25°C. The experimental techniques used by the six participating laboratories are Optical Digital Interferometry, Taylor Dispersion technique, Open Ended Capillary, Optical Beam Deflection, Thermogravitational technique and Sliding Symmetric Tubes technique in ground conditions and Selectable Optical Diagnostic Instrument (SODI) in microgravity conditions. The measurements obtained in the SODI installation have been analyzed independently by four laboratories. Benchmark values are proposed for the thermodiffusion and Soret coefficients and for the eigenvalues of the diffusion matrix in ground conditions, and for Soret coefficients in microgravity conditions.

This work deals with the study of dredged marine sand (DMS) from the Port of Sant Carles de la Ràpita (Tarragona, Spain) as construction material. The analysis of its\ud influence on paste, mortar and concrete production is described. Two experimental phases were carried out after the chemical and physical characteristics of DMS were determined. Firstly, pastes and mortars were made using CEM II/A-M 42.5R cement, different\ud percentages of DMS in replacement of raw sand and plasticizer additive in order to obtain the fresh and hardened properties of the mixes studied. After that, DMS was used for the production of concretes as fine aggregates. A pilot study was carried out with harbor concrete pavements produced at industrial scale. The results were compared to those of the control mixes and proved the satisfactory behavior of DMS as construction material when incorporated into concrete as granular corrector.Postprint (published version

We present a new type of thermogravitational (TG) column, a so-called TG microcolumn with transparent windows and a very small sample volume of less than 50 μL. The TG microcolumn has a planar geometry with a thickness of 0.523 ± 0.004 mm, a height of 30 mm, and a width of 3 mm. The concentration difference between two points at different heights is measured with an interferometer using active phase control. From the concentration difference we can determine the thermal diffusion coefficient, D(T), using the refractive index variation with concentration, which has to be determined independently. We studied the three binary mixtures of dodecane, isobutylbenzene, and 1,2,3,4-tetrahydronaphthalene with a concentration of 50 wt % at a temperature of 298 K. The thermal diffusion coefficients agree within a few percent with the proposed benchmark values. In addition we investigated also the binary mixture toluene/n-hexane and compare the results with literature values. For the investigated mixtures the typical measurement times were between 30 min and 2 h with an applied temperature difference of ΔT = 6 K.

In this work, the transport coefficients of the ternary mixtures of the diffusion coefficient measurements in ternary mixtures 1 project were determined. The analyzed ternary mixtures are formed by 1,2,3,4-tetrahydronaphthalene, isobutylbenzene, and dodecane (nC12) at different compositions. In all cases, the analysis was carried out at 25 °C. The thermodiffusion coefficients were measured by a new thermogravitational column, and the molecular diffusion coefficients were determined by the sliding symmetric tubes technique. Finally, the Soret coefficients were ascertained from the measurements of the thermodiffusion and molecular diffusion coefficients. In addition, two new quantitative correlations which enable the prediction of the thermodiffusion and Soret coefficients of a ternary mixture are presented. The comparison between the experimental and the predicted data shows a good agreement. The presented results help to complete the lack of experimental data in ternary mixtures. In addition, this work improves the fundamental understanding of multicomponent mixtures.

A new analytical methodology has been developed to determine the diagonal and cross-diagonal molecular diffusion coefficients in ternary mixtures by the Sliding Symmetric Tubes technique. The analytical solution is tested in binary mixtures obtaining good agreement with the results of the literature. Results are presented for the ternary mixture formed by tetralin, isobutylbenzene, and dodecane with an equal mass fraction for all the components (1-1-1) which is held at 25 °C. Diagonal and cross-diagonal coefficients are determined for the three possible orders of components, in order to compare the results with those available in the literature. A comparison with published results shows a good agreement for the eigenvalues of the diffusion matrix, and a reasonable agreement for the diagonal molecular diffusion coefficients.