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This paper presents findings obtained by evaluating the compressive strength, thermal conductivity, and durability of sand cylinder specimens stabilized with either epoxy emulsion (EM), acrylic polymer aqueous solution (APAS), EM-APAS mixture, or EM-APAS-lime mixture. Given the data obtained from the laboratory test, simulation analysis that uses a heat transfer fluid model of a ground-coupled heat pump (GCHP) system confirms the EM-APAS-lime binder performs best in the compressive strength and thermal conductivity; EM-APAS mixture performs best in the durability. However, the slake durability index of specimens containing EM-APAS-lime is equal to or greater than 80%. In addition, the compressive strength of sand stabilized with the EM-APAS-lime mixture is more than three times that of sand stabilized with cement. The thermal conductivity of sand stabilized with cement and that of sand treated with EM-APAS-lime mixture are 0.1 W/m·K and 0.9-1 W/m·K, respectively. It is confirmed that the heat collection of sand stabilized with EM-APAS-lime outperforms five times over that of sand stabilized with cement. These findings provide admissible evidence that the EM-APAS-lime mixture, which outperforms cement in compressive strength and thermal conductivity, is most suitable for ground improvement binder for GCHP systems.The development of antimicrobial polymers is a priority for engineers fighting microbial resistant strains. Silver ions and silver nanoparticles can assist in enhancing the antimicrobial properties of microcapsules that release such substances in time which prolongs the efficiency of antimicrobial effects. Therefore, this study aimed to functionalize different polymer surfaces with antimicrobial core/shell microcapsules. Microcapsules were made of sodium alginate in shell and filled with antimicrobial silver in their core prior to application on the surface of polymer materials by dip-coating methodology. Characterization of polymers after functionalization was performed by several spectroscopic and microscopic techniques. After the characterization of polymers before and after the functionalization, the release of the active substances was monitored in time. The obtained test results can help with the calculation on the minimal concentration of antimicrobial silver that is encapsulated to achieve the desired amounts of release over time.Wet foam can be used as a carrier in the manufacturing of lightweight materials based on natural and man-made fibers and specific additives. Using a foam forming method and cellulose fibers, it is possible to produce the porous materials with large area of end-using such as protective and cushioning packaging, filtering, hydroponic, thermal and sound absorption insulation, or other building materials. In comparison with the water-forming used for conventional paper products, foam-forming method provides many advantages. In particular, since fibers inside the foam are mostly trapped between the foam bubbles, the formed materials have an excellent homogeneity. This allows for using long fibers and a high consistency in head box without significant fiber flocking. As result, important savings in water and energy consumptions for dewatering and drying of the foam formed materials are obtained. In cushioning packaging, foam-formed cellulose materials have their specific advantages comparing to other biodegradable packaging (corrugated board, molded pulp) and can be a sustainable alternative to existing synthetic foams (i.e., expanded polystyrene or polyurethane foams). This review discusses the technical parameters to be controlled during foam forming of cellulose materials to ensure their performances as cushioning and protective packaging. Y-27632 research buy The focus was on the identification of practical solutions to compensate the strength decreasing caused by reduced density and low resistance to water of foam formed cellulose materials.Every application of a substance results from the macroscopic property of the substance that is related to the substance's microscopic structure. For example, the forged park gate in your city was produced thanks to the malleability and ductility of metals, which are related to the ability of shifting of layers of metal cations, while fire extinguishing powders use the high boiling point of compounds related to their regular ionic and covalent structures. This also applies to polymers. The purpose of this review is to summarise and present information on selected food-related biopolymers, with special attention on their respective structures, related properties, and resultant applications. Moreover, this paper also highlights how the treatment method used affects the structure, properties, and, hence, applications of some polysaccharides. Despite a strong focus on food-related biopolymers, this review is addressed to a broad community of both material engineers and food researchers.The paper presents new value-added composite materials prepared by recycling tire rubber, polyethene terephthalate (PET), high-density polyethene (HDPE), wood sawdust, and fly ash. The composites were manufactured through the compression molding technique for three temperatures (150 °C, 160 °C, and 190 °C) previously optimized. The addition of fly ash as reinforcement in polymer blends is a viable route to improve the composite" properties. The paper aims to assess the effect of fly ash on the mechanical properties and water stability of the new all waste composites considering their applications as outdoor products. The static tensile (stress-strain behavior) and compression properties of the composites were tested. The fly ash composites were characterized in terms of wetting behavior and surface energies (contact angle measurements); chemical structure of the new interface developed between composite" components (FTIR analysis), crystalline structure (XRD analysis), surface morphology and topography (SEM, AFM). The addition of fly ash promoted the development of the hybrid interfaces in the new composites, as FTIR analysis has shown, which, in turn, greatly improved the mechanical and water resistance. The novel all waste composites exhibited lower surface energies, larger contact angles, and smoother morphologies when compared to those with no fly ash. Overall, the study results have revealed that fly ash has improved the mechanical strength and water stability of the composites through the formation of strong hybrid interfaces. The study results show optimal water stability and tensile strength for 0.5% fly ash composites cured at 190 °C and optimal compressive strength with good water stability for 1% fly ash composite cured at 150 °C.This study proposes to use reactive copolymers based on glycidyl methacrylate and fluoroalkyl methacrylates with a low fluorine content in the monomer unit as agents to reduce the surface free energy (SFE). This work reveals the effect of the structure and composition of copolymers on the SFE and water-repellent properties of these coatings. On a smooth surface, coatings based on copolymers of glycidyl methacrylate and fluoroalkyl methacrylates with fluorine atoms in the monomer unit ranging from three to seven are characterized by SFE values in the range from 25 to 13 mN/m, which is comparable to the values for polyhedral oligomeric silsesquioxanes and perfluoroalkyl acrylates. On textured aluminum surfaces, the obtained coatings provide time-stable superhydrophobic properties with contact angles up to 170° and sliding angles up to 2°. The possibility of using copolymers based on glycidyl methacrylate and fluoroalkyl methacrylates for the creation of self-cleaning polymer coatings is shown.Although several sample preparation methods for analyzing microplastics (MPs) in environmental matrices have been implemented in recent years, important uncertainties and criticalities in the approaches adopted still persist. Preliminary purification of samples, based on oxidative digestion, is an important phase to isolate microplastics from the environmental matrix; it should guarantee both efficacy and minimal damage to the particles. In this context, our study aims to evaluate Fenton's reaction digestion pre-treatment used to isolate and extract microplastics from environmental matrices. We evaluated the particle recovery efficiency and the impact of the oxidation method on the integrity of the MPs subjected to digestion considering different particles' polymeric composition, size, and morphology. For this purpose, two laboratory experiments were set up the first one to evaluate the efficacy of various digestion protocols in the MPs extraction from a complex matrix, and the second one to assess the possible harm of different treatments, differing in temperatures and volume reagents used, on virgin and aged MPs. Morphological, physicochemical, and dimensional changes were verified by Scanning Electron Microscope (SEM) and Fourier Transformed Infrared (FTIR) spectroscopy. The findings of the first experiment showed the greatest difference in recovery rates especially for polyvinyl chloride and polyethylene terephthalate particles, indicating the role of temperature and the kind of polymer as the major factors influencing MPs extraction. In the second experiment, the SEM analysis revealed morphological and particle size alterations of various entities, in particular for the particles treated at 75 °C and with major evident alterations of aged MPs to virgin ones. In conclusion, this study highlights how several factors, including temperature and polymer, influence the integrity of the particles altering the quality of the final data.The effects of the type and content of fibers, water to cement ratio (W/C), and content of cementitious materials on the shrinkage and creep of ultra-high performance concrete (UHPC) were investigated. The relationships between curing age, shrinkage, and unit creep of the UHPC were also discussed. The results showed that the shrinkage of the UHPC decreased with the increase in W/C, where there existed a quadratic function between shrinkage and W/C. However, the unit creep of the UHPC increased with W/C. The shrinkage and unit creep of the UHPC increased with the increase in the content of the cementitious materials. The type and content of fibers had different effects on the shrinkage and unit creep of the UHPC, that is, the shrinkage of the UHPC first increased and then decreased with the increase in the content of steel fibers, where there existed a quadratic function between them. There was a linear function between the shrinkage of the UHPC and the content of carbon fibers, but the shrinkage of the UHCP first increased and then decreased with the increase in PVA content. The shrinkage and unit creep of the UHPC at the initial curing age were significant, which tended to be constant with the increase in curing age. Although the steel fibers had a significant inhibiting effect on the unit creep of the UHPC, the carbon fibers and PVA had positive and negative effects on the unit creep of the UHPC. The effects of the type and content of fibers on the shrinkage and unit creep of the UHPC were caused by the slenderness ratio, shape, surface roughness, and elasticity modulus of the fibers. The shrinkage and creep of the UHPC were caused by the chemical autogenous shrinkage and free water evaporation of the UHPC.

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