Agro-industrial valorization of Satsuma mandarin peels is typically limited to pectin or essential oils, often neglecting valuable non-volatile bioactives. This study investigates high-pressure homogenization (HPH) as an intensive microstructural disruption strategy to recover matrix-bound bioactives and obtain physically stable multi-phase plant-derived fluid systems using water or oil-in-water (o/w) mixtures. HPH treatment (up to 10 passes) effectively disrupted the cellular matrix, achieving a similar to 2.6-fold particle size reduction. In aqueous systems, 5 passes maximized the recovery of total polyphenols and carotenoids. Remarkably, this water-only process achieved total carotenoid analytical accessibility statistically comparable to exhaustive conventional solvent extraction with acetone, indicating that intense physical disruption can effectively liberate sequestered lipophilic compounds without the primary use of organic solvents. In o/w systems, processing enabled a passive physical partitioning of compounds driven by their respective chemical polarities. Mass balance tracking across the physical fractions indicated that lipophilic carotenoids and polymethoxylated flavones (PMFs) preferentially partitioned into the lipid-rich cream phase, while hydrophilic flavonoids (e.g., narirutin) remained in the continuous serum layer. Chromatographic phase profiles and serum depletion data supported these distinct distribution trends for PMFs (e.g., nobiletin) and carotenoids. Isothermal calorimetry validated the functional protective capacity of the resulting colloidal system: the incorporation of 1% HPH-treated peel powder significantly delayed lipid autooxidation in exogenous linseed oil model, yielding an induction time superior to a purified resveratrol standard. These findings demonstrate that HPH effectively releases and distributes mandarin peel bioactives into distinct, multi-phase fluid matrices, offering a sustainable, solvent-free processing pathway for the valorization of citrus by-products.
Polymer nanocomposites incorporating electrically conductive nanostructured fillers are increasingly investigated as multifunctional materials capable of addressing functional requirements across a broad range of applications, from biomedical devices to industrial load-bearing materials and structures. Recent studies have suggested that this class of nanocomposites can be designed to exhibit electrically activated healing, restoring electrical percolation and mechanical integrity. This research focuses on this peculiar self-healing process, evaluating both its general applicability, even to polymers whose molecular structures were not designed to be "healed", and its effectiveness in restoring electrical, mechanical, and structural continuity in polymer nanocomposites. The restoration occurs through a sort of migration of nanoparticles with attached polymer chains toward the damaged region, thereby restoring the functional and molecular nanocomposite architecture. The electric-field-assisted nanofiller redistribution in the damaged region following restoration is experimentally verified by Tunneling Atomic Force Microscopy (AFM-TUNA). The recovery of the mechanical integrity of the polymer nanocomposites after the electro-healing process is further evaluated through dedicated airtightness tests performed before and after damage and subsequent healing. To enable electro-healing, multiwalled carbon nanotubes (MWCNTs) were used as conductive nanofillers. Three polymer matrices, poly(ethylene-co-methacrylic acid) (EMAAc), thermoplastic vulcanizate polypropylene (TVPP), and acrylonitrile butadiene styrene (ABS), were selected to investigate the generality of electro-healing behavior and to assess its potential applicability across diverse material systems and application fields. The results highlight that electro-healing can repair damage initiation up to spatial scales of micrometers or several millimeters and can be successfully applied to load-bearing composite structures.
This study evaluates the potential of Advanced Wet Friction Milling (AWFM) as a high-throughput and high-concentration alternative to High-Pressure Homogenization (HPH) for the micronization and cell disruption of recalcitrant biomass. HPH industrial scalability is fundamentally restricted by low solid loading boundaries, high clogging risk, and thermal degradation over extended cycles. To demonstrate the efficiency of AWFM, this work evaluated the fluid-mechanical disruption of spent coffee grounds (SCG) as a highly cross-linked biomass model system. AWFM processed SCG at 1:1 w/w wet SCG-to-water ratio (19.5 wt% dry matter), compared with 1:4 w/w wet basis (7.8 wt% dry matter) for HPH. Particle size distribution and morphological analyses revealed that the synchronized compression, intense spatial shear, and rolling friction generated between the adjustable non-porous discs of the AWFM platform achieved accelerated structural breakdown; notably, after pretreatment and two zero-gap passes (AWFM-P2), D[3,2] and D[4,3] were comparable to those after high-shear mixing and five HPH passes.Peak extraction was achieved after four AWFM passes, yielding a total phenolic content (TPC) of 27.09 ± 0.41 mg GAE/g SCG and total flavonoid content (TFC) of 35.34 ± 0.30 mg QE/g SCG. Furthermore, DPPH and FRAP were higher for AWFM-P4 than for HPH-5, TPC was comparable and TFC was lower. These findings indicate AWFM as a promising high-solids option with a low temperature rise; scalability requires further validation.
In this paper, we analyze a linearized model for incompressible transversely isotropic dispersive fiber-reinforced materials in which both the elastic and dispersive properties depend on the direction of the fibers. We investigate the motions in bodies made of these materials that are subjected to prescribed shear or normal action on part of the rigid boundaries. In the case where the motion is induced by shear stresses acting at the boundary, we provide the analytical solution for the displacement field from which we derive the components of the stress tensor. In the case where the motion is due to the action of normal stresses at the boundary, the initial and boundary value problem is solved using a projection algorithm based on spectral methods. In both cases, we quantify how anisotropic dispersion and material stiffness affect the displacement field.
