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The advanced synthetic and natural materials, such as piezoelectric ceramics, electroactive polymers and biological soft tissues, exhibit the multi‐physical or physicochemical coupling behaviors. The coupling behavior involves the thermal‐mechanical, electric‐mechanical and electrochemicalmechanical interactions. The coupling phenomena can be modeled in the microscopic and macroscopic levels. In the microscale, the material consists of the solid, fluid and ions. The domain FE technique can be used to model the deformation of the solid and the flow of the fluid. In the macroscale, the mixture theory can be applied to description of the coupled response of the continuum under coupled thermal, electrical, chemical and mechanical loadings. A weak form of the governing equations is established by means of variational principle and a multi‐field finite element (MFE) method is developed for numerical modeling of the coupling behavior of advanced materials.

Urban beekeeping is spreading as an answer to promote bee conservation and to develop local economies. This study aims to highlight nutritional properties of polyfloral honeys produced in urban landscape and to compare them to the countryside counterparts.

This research has examined polyfloral urban honeys from a restricted area in Central Italy, for antioxidant capacity, total phenolic content and 15 polyphenols profile. Physicochemical parameters have been also determined to assess the overall quality of the samples. Results were compared with polyfloral honeys produced in surrounding countryside and monitored in two harvest years, 2018 and 2019. Principal component analysis was applied to the data to disclose significant differences among honeys and harvest years.

Urban honeys revealed up to threefold higher total amount of polyphenols with respect to rural honeys, and in the 2019 harvest, despite water scarcity that affected the national production, demonstrated 50% higher antioxidant capacity and total phenolic content. The majority of the 15 polyphenols studied resulted in more abundant urban honeys, in particular in the 2019 harvest. The multivariate analysis evidenced how honeys could be successfully separated according to their production area and harvest year by their different polyphenols profile.

Limited data are available on nutritional properties of urban honeys and on their content in antioxidants. The present results suggest that the cultivated urban environment, with its large floral biodiversity, can provide extra nutrition for bees, resulting in the production of a honey rich in nutraceutical compounds.

Studies on the surface modification of sodium‐aluminium silicate P‐820 using silane coupling agents are described. The best modifiers were selected, which induced a change of the silicate surface from hydrophilic to hydrophobic. Physicochemical analyses of the modified silicate were performed. The methods of evaluating silicate surface modification degree were presented. The degree of hydrophobization of silicate surface was determined by a calorimetric method. Near infra‐red spectroscopy (NIR) was used to determine the degree of condensation of the silicate surface silanol groups. Studies on morphology and microstructure using transmission electron microscopy (TEM) were performed. Attempts were made to apply the unmodified and modified sodium‐aluminium silicate P‐820 as filler and pigment in silicate and dispersion paints.

An attempt was made to precipitate highly dispersed carbonate‐silicate fillers from solutions of metasilicate sodium and calcium hydroxide using gaseous carbon dioxide. Optimum conditions were defined for precipitating these powders. Carbonate‐silicate fillers were subjected to surface modification employing two techniques: the wet one, applied in the course of precipitation, and the dry one. For the modification, silane coupling agents were used. The carbonate‐silicate fillers were subjected to physicochemical analysis. Moreover, particle size distribution was determined using the DLS technique and their surface morphology was examined using SEM. The modified carbonate‐silicate filler was applied as a substitute of titanium white and a filler in acrylic paints.i

In this study, titanium white was investigated, covered with aluminium oxide and silica. The titanium white was produced by Chemical Works Police S.A. under the catalogue symbol of R‐210. Surface of titanium white was modified with silane coupling agents, such as 3‐methacryloxypropyltrimethoxysilane (A‐174), vinyltrimethoxysilane (U‐611) and N‐2‐(aminoethyl)‐3‐aminopropyltrimethoxysilane (U‐15D). The unmodified and the modified titanium white was subjected to physicochemical analysis. Moreover, tests were performed aiming at defining morphology, surface structure, and dispersion of the particles as related to, first of all, the type of applied modifier. Product evaluation took advantage of modern investigative techniques, including SEM and DLS. Modified and unmodified titanium whites were applied as pigments in acrylic paints. The modified Titanium dioxide in particular improved strength and utility properties of studied paints.

The surface character of titanium dioxide (rutile) was altered by surface modification. Silane coupling agents were used as modifiers. Physicochemical properties of the obtained products were evaluated. Effects of the modifier concentration on changes in hydrophilic/hydrophobic properties of the surface were estimated. The tendency to form primary and secondary agglomerate structures was defined using dynamic light scattering and examining morphology and surface structure with the use of scanning electron microscopy. Specific surface area and pore volume were also measured in unmodified and modified titanium white.

Surface of precipitated silica was modified with 3‐aminopropyltriethoxysilane. The optimum solvent was selected, in which the silane coupling agent was deposited on silica surface. Basic physicochemical properties of the modified silica were estimated. Methods of evaluating silica surface modification extent were presented, taking advantage first of all of its altered hydrophilicity and of differences in condensation extent of surface silanol groups. The modified silica was used as adsorbent capable of trapping water soluble organic amines.

Studies were carried out on the modification of silica with 3‐aminopropyltriethoxysilane in various solvents. The modified silica obtained was subjected to comprehensive evaluations of physicochemical properties, including the bulk density and the capacities to absorb water, dibutyl phthalate and paraffin oil. Particle size, particle size distribution, uniformity of the particles, tendency to form agglomerates, as well as particle surface morphology, were also examined using SEM and dynamic light scattering (DLS) techniques. The properties of the modified silica obtained were compared to evaluate the effects of the solvents used during the surface modification of the silica.

The surface of pyrogenic silica was modified with silane coupling agent, such as N‐2‐(aminoethyl)‐3‐aminopropyltrimethoxysilane. Pigments were obtained by attaching different organic dyes, to a modified silica surface. The adsorption process was conducted in an aqueous suspension of the modified silica in the presence of the dye. In order to determine effect of silane on the dye adsorption process various amounts of the modifying compound was used. The microscopic properties, colour and particle size distribution were examined for the modified silicas and the obtained pigments.

Presents the outcome of intensive research into highly dispersed sodium‐aluminium silicate. Optimal conditions of the precipitation process of sodium‐aluminium silicates of high dispersion degrees from the solution of sodium metasilicate were given. In the precipitation process water soluble aluminium salts were used. A physicochemical analysis and microscopic structure of the obtained silicates were performed. The products obtained are characterized by parameters comparable to those of the sodium‐aluminium silicate P‐820 (Degussa).