Silica–wollastonite xerogel composites (xerocomposites) with different wollastonite filler content were obtained after classical drying of silica–wollastonite gels. Two different silica precursors were used, TEOS and colloidal LUDOX, for composites named TW and LW, respectively. We utilized SAXS experiments, N2 adsorption–desorption, and SEM techniques to determine the textural and structural properties of these porous materials. For both the TW and LW composites, it was shown that a macroporosity and a mesoporosity coexist. We argue that the proportion of macroporosity directly depends on the proportion of wollastonite fillers in the composite. We propose a unique two-stage drying mechanism to explain the formation of macropores. We additionally found that the surface of wollastonite fillers was covered by a dense multilayer packing of silica colloids in LUDOX LW xerocomposites. We believe that these surface-modified wollastonite fillers could improve the carbonation kinetics of wollastonite when used as a precursor for aqueous mineral carbonation, a promising route for safe and durable carbon sequestration.

Silica-wollastonite xerogel composites (xerocomposites) with different wollastonite filler content were obtained after classical drying of silica-wollastonite gels. Two different silica precursors were used, TEOS and colloidal LUDOX, for composites named TW and LW, respectively. We utilized SAXS experiments, N2 adsorption-desorption, and SEM techniques to determine the textural and structural properties of these porous materials. For both the TW and LW composites, it was shown that a macroporosity and a mesoporosity coexist. We argue that the proportion of macroporosity directly depends on the proportion of wollastonite fillers in the composite. We propose a unique two-stage drying mechanism to explain the formation of macropores. We additionally found that the surface of wollastonite fillers was covered by a dense multilayer packing of silica colloids in LUDOX LW xerocomposites. We believe that these surface-modified wollastonite fillers could improve the carbonation kinetics of wollastonite when used as a precursor for aqueous mineral carbonation, a promising route for safe and durable carbon sequestration.

Microfluidics is one of the most fascinating fields that researchers have been trying to apply in a large number of scientific disciplines over the past two decades. Among them, the discipline of food and pharmaceutical formulation encountered several obstacles when combining microfluidics with aqueous media. Indeed, the physical properties of liquids at micrometric volumes being particular, the droplet generation within microfluidic devices is a big challenge to be met. This focus review is intended to be an initiation for those who would like to generate microdroplets in microfluidic systems involving aqueous continuous phases. It provides a state-of-the-art look at such systems while focusing on the microfluidic devices used, their applications to form a wide variety of emulsions and particles, and the key role held by the interface between the device channels and the emulsion. This review also leads to reflections on new materials that can be used in microfluidic systems with aqueous continuous phases.

We calculate the trajectory of a moving object on earth and the trajectory of the earth around the sun in a fourdimensional space (x, y, z, t). We see that the trajectory has a mass: this is what is called dark matter which mass depends on the mass of the moving object. Indeed the deformation of space, the track, deviates light as we are at the hypersurface of the universe, and that is the method of measurement of the ’mass’ of the universe.

This work reports on the effect of substituting Al2O3 for P2O5 and substituting CaO for (Na2O+K2O) in the ternary 0,46 (K2O + Na2O) 0,54 P2O5 glass system, certain of these compositions being eventually of interest for bio-medical applications. Different properties are analysed here. When CaO replaces (Na2O+K2O) (constant O/P ratio) or when Al2O3 replaces P2O5 (increasing O/P ratio), it is shown that the density of the glasses increased, the coefficient of thermal expansion decreased and the glass transition temperature increased. A partial and limited study of dissolution behaviour in water indicates that the dissolution rates decreased by orders of magnitude with the introduction of CaO or Al2O3, in agreement with the trends reported in the literature. The pH values of the dissolution solutions were also measured. The pH quickly decreased and saturated to around 2.5 for glasses with no alumina, i.e with the highest P2O5 content. On another hand, when Al2O3 was substituted for P2O5 (i.e. when P2O5 content decreased and O/P increased), the pH initially increased to more basic values (around 7) and always remained above 5. Some interpretation of the structural role of CaO and Al2O3 are proposed to explain these properties change with composition.

A comprehensive characterization of physical-chemical properties and biological interactions of ca. 200-nm-thick hybrid films based on silylated (inorganic part) castor oil (organic part) is proposed. A series of such nanofilms was fabricated and cross-linked by a sol-gel procedure, and their properties such as hydrophilicity, hardness and water vapour transmission rate were systematically studied as a function of the ratio of silylated agent to castor oil. It was found that the nanofilms have contact angles always below 90°, tunable Young modulus and hardness in the MPa range. Moreover, their water vapour transmission rates are increased by decreasing the silica ratio. The protein adsorption and cytocompatibility were evaluated using model proteins and cells. The adsorption of the proteins bovine serum albumin (BSA) and lysozyme was characterized using a quartz crystal microbalance in energy dissipation mode (QCM-D), and atomic force microscopy (AFM). The combination of the latter provided evidence for the different affinities of the proteins with the films. It was found that BSA and lysozyme form rigid layers on the surface with surface coverage close to 30%, and that both protein layers decrease their thickness after their dehydration. Finally, cell culture experiments exhibited a good viability of the fibroblasts compared to ultra-low adhesion surfaces, which makes them potential candidates for biomedical applications.