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Encapsulation revolutionizes industries through enhanced stability, controlled release, and targeted performance of active ingredients. The novel aspect of this study explores the impact of the wall material-to-active (WM:A) ratio on the stability of ascorbic acid (AA) encapsulated in a maltodextrin (MD) and gum arabic (GA) blend (2:1 w/w ). Microparticles were spray-dried and analyzed using SEM, TGA, DSC, thermal stability, and antioxidant activity assessments. Stability tests under different conditions revealed that a higher WM:A ratio (7:1) improved the active stability and antioxidant activity during storage, highlighting its importance in the encapsulation process. SEM analysis confirmed particles with no cracks, and the particles demonstrated excellent thermal stability up to 200 °C with minimal degradation. These findings underscore the critical role of the WM:A ratio in determining the stability of encapsulated AA within a carbohydrate matrix, offering valuable insights for advancing encapsulation technologies.

Hypothesis: The temperature dependence of the static contact angle could a priori be predicted by using surface tension partitioning. An original model based on the transition state theory is also introduced. This model considers thermocapillary fluctuations on the droplet surface near the triple line and the self-affine pinning of this triple line against a solid substrate modeled with a pseudo-periodic distribution of adsorption sites., Experiments: The temperature dependence of the static contact angle was studied for a representative range of liquids with different polarities and on a wide array of solid substrates for temperatures ranging from 25 to 240 °C. Atomic force microscopy (AFM) was also used to quantify the surface roughness of the solid substrates., Findings: Whereas the surface tension partitioning failed to bring consistent results above room temperature, the transition state model proved very useful, thereby opening a way to yield predictive contact angle values with temperature variations. The introduction of a topological dimension in the equations yields a unified model that covers normal wetting (perfectly bonded liquids on smooth surfaces) but also the onset of Cassie-Baxter and Wenzel states on real surfaces. Moreover, the model encompasses the transition to complete wetting., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier Inc. All rights reserved.)

A cotransport study of heavy metals and kaolinite particles in sand column with and without flax geotextiles was carried out. The objectives were to evaluate the potential role of kaolinite in heavy metals transfer and to analyse the influence of flax geotextiles on the transfer of these pollutants. The adsorption rates of heavy metals on the kaolinite particles were, respectively, 53%, 65% and 25% for copper, lead, and zinc. The injection of kaolinite with heavy metals resulted in a significant decrease in the retention efficiency of copper and lead in the filter. The presence of kaolinite in the injected solution has virtually no influence on the effectiveness of zinc fixation in the filter. The retention of heavy metals is in the order of Zn > Cu > Pb with a significant drop of retention efficiency of 34% for copper, 67% for lead, and less than 1% for zinc. The presence of kaolinite in the injected solution reversed the retention order of heavy metals when metals solution was injected alone. Flax geotextiles increase the ability of the filter to retain soluble and attached heavy metals. It improves the sand retention capacity and it retains soluble and attached metals in its structure.

Cellulose nanocrystals (CNC) and xyloglucan (XG) were used to construct new aerogels inspired by the hierarchical organization of wood tissue, i.e., anisotropic porous cellular solid with pore walls containing oriented and stiff cellulose nanorods embedded in hemicellulose matrix. Aerogels with oriented or disordered pores were prepared by directional and non-directional freeze-casting from colloidal dispersions of XG and CNC at different ratios. XG addition induced a clear improvement of the mechanical properties compared to the CNC aerogel, as indicated by the Young modulus increase from 138 kPa to 610 kPa. The addition of XG changed the pore morphology from lamellar to alveolar and it also decreased the CNC orientation (the Hermans' orientation factor was 0.52 for CNC vs 0.36-0.40 for CNC-XG). The aerogels that contained the highest proportion of XG also retained their structural integrity in water without any chemical modification. These results open the route to biobased water-resistant materials by an easy and green strategy based on polymer adsorption rather than chemical crosslinking., (Copyright © 2020. Published by Elsevier Ltd.)

To overcome water scarcity issues in arid and semi-arid regions, Managed Aquifer Recharge (MAR) remains a viable and suitable solution to manage and restore aquifers. However, clogging represents a major issue that can affect the durability and efficiency of MAR structures. The aim of this study was to evaluate the extent of clogging in MAR sites (Berrechid, Morocco). To achieve this objective, two field-based studies were undertaken: the first one consists of implantation of sand-filled columns in the recharge sites to evaluate the surface and subsurface clogging. The second one consists of the implantation of pickets over a 750 m 2 area in each recharge site to measure the extent of deposit thickness on the surface of the wadi bed. Results show that, despite the low rainfall (<1.4 mm/day) and the short period (91 days) of the study, the deposits thickness exceeds 3 cm in a large part of the MAR. The suspended solids concentrations measured in recharge sites ranged from 1.1 to 1.4 g/L. Due to the particles retention, the estimation of the saturated hydraulic conductivity (k) of the sand declines over 90% in the immediate entrance of the columns. The k values measured in situ during the drying period ranged from 10 -5 to 10 -6  m/s. The k values of the cake formed, without cracks, was about 10 -8  m/s. The presence of cracks drives the entire infiltration. However, due to the high plasticity index of the MAR soil, a slight reduction of cracks opening during wetting cycles is observed. In addition, particles deposited in these cracks, would contribute actively to the reduction of infiltration. The results of this study clearly showed the MAR sites vulnerability in semi-arid regions due to physical clogging., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Filtration tests were carried out in laboratory columns filled with crushed sand with and without flax geotextiles to study the transfer and retention of soluble heavy metals. Divalent cations of copper, zinc and lead were simultaneously and continuously injected in filtration columns. Results show that, when geotextiles discs are present the retention of metals in sand is favoured and retention profiles are modified. In addition, and unlike synthetic geotextiles, flax fibres geotextiles contribute to the retention of a significant fraction of the cationic metal pollutants in their own structure. The overall metals retention efficiency of the filter is improved. Competition between cationic metals for adsorption on retention sites occurs in the column in the order Pb > Cu > Zn. Most of the lead is retained in the inlet of the column while copper and even more zinc migrate deeper in the column.

In this work, the properties of cellulose (CE)/xyloglucan (XG) biopolymer blends are investigated, taking inspiration from the outstanding mechanical properties of plant cell walls. CE and XG were first co-solubilized in an ionic liquid, 1-ethyl-3-methylimidazolium acetate, in order to blend these biopolymers with a varying CE:XG ratio. The biopolymers were then regenerated together using water to produce solid blends in the form of films. Water-soluble XG persisted in the films following regeneration in water, indicating an attractive interaction between the CE and XG. The final CE:XG ratio of the blends was close to the initial value in solutions, further suggesting that intimate mixing takes place between CE and XG. The resulting CE/XG films were found to be free of ionic liquid, transparent and with no evidence of phase separation at the micron scale. The mechanical properties of the blend with a CE:XG ratio close to one revealed a synergistic effect for which a maximum in the elongation and stress at break was observed in combination with a high elastic modulus. Atomic force microscopy indicates a co-continuous nanostructure for this composition. It is proposed that the non-monotonous variation of the mechanical performance of the films with XG content is due to this observed nanostructuration., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

In Morocco, wheat production shows a high inter-annual variability due to uncertain rainfall. In view of the importance of this resource to the country's economy, it is important to gain a better understanding of the natural large-scale climate oscillation governing this variability. In this study, we analyzed de-trended (1) time series of common wheat yields (1983-2008) from 11 agricultural provinces that account for 80% of national wheat production; (2) monthly rainfall and 10-day temperature from ten meteorological stations; (3) 10-day normalized difference vegetation index (NDVI) from the AVHRR sensor; (4) monthly atmospheric climate indices [North Atlantic Oscillation (NAO) and Scandinavian Pattern (SCA)] and monthly 500 hPa geopotentials fields; and (5) monthly sea surface temperature (SST) fields and indices (NIÑO3, Tropical North Atlantic and Tropical South Atlantic). The relationship between rainfall and temperature during tillering in early winter and grain filling in early spring and wheat yields already observed at the plot scale was also found to be significant at the provincial scale. The linkages between wheat yields and large scale climate have been analyzed for the first time over Morocco. In agreement with previous studies, results show a complex and competing influence of different climate phenomena. The NAO is found to be significantly related to yields during the early stage of wheat growth in December, whereas the SCA correlates with yields later in the season, in January and February. Interesting lagged correlations with higher lead time are also highlighted, with the leading modes of SST variability in the equatorial Atlantic during October (the "Atlantic Niño" mode) and in the North Atlantic (the "Atlantic tripole" mode) in February. Our conclusion is that regional climate indices and variables represent valuable information with which to increase lead time and skill regarding wheat yield predictions in Morocco.