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Human milk provides bioactive compounds such as milk fat globules (MFGs), which promote brain development, modulate the immune system, and hold antimicrobial properties. To ensure microbiological safety, donor milk banks apply heat treatments. This study compares the effects of heat treatments and homogenization on MFGs physicochemical properties, bioactivity, and bioavailability. Vat pasteurization (Vat-PT), retort (RTR), and ultra-high temperature (UHT) were performed with or without homogenization. UHT, RTR, and homogenization increased the colloidal dispersion of globules, as indicated by increased zeta potential. The RTR treatment completely inactivated xanthine oxidase activity (a marker of MFG bioactivity), whereas UHT reduced its activity by 93%. Interestingly, Vat-PT resulted in less damage, with 28% activity retention. Sialic acid, an important compound for brain health, was unaffected by processing. Importantly, homogenization increased the in vitro lipolysis of MFG, suggesting that this treatment could increase the digestibility of MFG. In terms of color, homogenization led to higher L* values, indicating increased whiteness due to finer dispersion of the fat and casein micelles (and thus greater light scattering), whereas UHT and RTR increased b* values associated with Maillard reactions. This study highlights the nuanced effects of processing conditions on MFG properties, emphasizing the retention of native characteristics in Vat-PT-treated human milk.

This study develops a thermal homogenization model for an aluminum honeycomb panel using the representative volume element (RVE) concept, considering the orthotropic nature of the structure. The RVE thermal homogenization method is a numerical approach for analyzing heterogeneous materials. It employs a constitutive model based on RVE performance to represent thermal behavior. Effective parameters are determined through averaging techniques, and the finite element method solves the thermal problem, accounting for structure topology and material behavior. The resulting heat conduction problem is solved using the finite element method (FEM) to evaluate the effective thermal characteristics. A 3D RVE is generated based on the honeycomb panel's geometry, evaluating thermal conductivity tensor and describing the medium's thermal performance. Numerical tests validate the model by comparing it with the real honeycomb structure under sinusoidal heat flux. Results show good correlation, with maximum temperatures of 1101.9 °C in the real structure and 1096.4 °C in the medium. The homogeneous medium is further used to investigate thermal performance under convective conditions with varying panel thicknesses, achieving over 77 °C temperature reduction with the thickest panel. Natural vibration behavior is considered, demonstrating strong correlation between modal responses and natural frequencies. This modeling approach efficiently analyzes thermal behavior in large honeycomb structures, reducing computational time significantly.

Herein, an efficient homogenization procedure is extended based on a Haydock representation of the microscopic wave operator for the calculation of the retarded macroscopic dielectric response of a binary periodic composite to the case of an arbitrary number of components of arbitrary composition. As a test, this numerical procedure is applied to the calculation of the optical properties of a Bouligand structure, made up of a large number of anisotropic layers stacked on top of each other and progressively rotated. This system constitutes a photonic crystal with circularly polarized electromagnetic normal modes, naturally occurring in the cuticle of several arthropods. It presents a gap for one helicity, which corresponds to the observation of circularly polarized strong metallic like reflections. This numerical procedure is validated through its good agreement with the results of alternative formulations, including an analytical solution for this simple chiral system. [ABSTRACT FROM AUTHOR]

While direct homogenisation approaches such as the FE 2$$ {}^2 $$ method are subject to the assumption of scale separation, the mesh‐in‐element (MIEL) approach is based on an approach with strong scale coupling, which is based on a discretization with finite elements. In this contribution we propose a two‐scale MIEL scheme in the framework of the theory of porous media (TPM). This work is a further development of the MIEL method which is based on the works of the authors A. Ibrahimbegovic, R.L. Taylor, D. Markovic, H.G. Matthies, R. Niekamp (in alphabetical order); where we find the physical and mathematical as well as the software coupling implementation aspects of the multi‐scale modeling of heterogeneous structures with inelastic constitutive behaviour, see for example, [Eng Comput, 2005;22(5‐6):664‐683.] and [Eng Comput, 2009;26(1/2):6‐28.]. Within the scope of this contribution, the necessary theoretical foundations of TPM are provided and the special features of the algorithmic implementation in the context of the MIEL method are worked out. Their fusion is investigated in representative numerical examples to evaluate the characteristics of this approach and to determine its range of application. [ABSTRACT FROM AUTHOR]

A numerical technique for the homogenization of the thermal conductivity properties of woven composites using a two-level approach was developed. At the microscale level, the averaged thermal conductivity characteristics of a strand were calculated based on the given properties of carbon fibers and epoxy matrix. At the macroscale level, a representative volume of the woven composite was homogenized, and components of the thermal conductivity tensor of equivalent homogeneous material were determined. In this case, the effective thermal conductivity characteristics of the strands found at the first level of homogenization were used. The finite element method was applied for the solution of stationary heat conduction problems. For a composite based on plain weave fabric, economical representative volumes were constructed, and systems of boundary conditions required at each level of modeling were formulated. Numerical results were presented for different packing densities of fibers in strands. [ABSTRACT FROM AUTHOR]

The causes of the formation of bumps on metallographic specimens of sheets and strips subject to inspection are established by analyzing the components of Kovar alloy (trademarked name of Fe29%Ni18%Co precision alloy; named 29NK-VI in Russia) and identifying possible deviations from its manufacturing process, starting from the preparation of the initial melt. It was found out that the formation of bumps is a manifestation of leading diffusion of some alloy components into others, mainly cobalt into nickel. Such a phenomenon may occur in case of significant chemical inhomogeneity of the metallic material caused by the segregation of the components of its initial melt according to their magnetic susceptibility and the refusal to homogenize the resulting ingot. It is argued that bumps on specimens should be considered as a rejection criterion for a material intended for the manufacture of precision parts of vacuum electronic devices, as they are indicative of its unbalanced composition. The residual diffusion phenomena contribute to the change in the phase state of the material, followed by embrittlement, change in precise dimensions, and loss of vacuum in parts of vacuum electronic devices. It is assumed that residual diffusion is one of the causes of the γ→α phase transformation in Kovar at low temperatures. [ABSTRACT FROM AUTHOR]

Recent studies have focused on the development of bio-based products from sustainable resources using green extraction approaches, especially nanocellulose, an emerging nanoparticle with impressive properties and multiple applications. Despite the various sources of cellulose nanofibers, the search for alternative resources that replace wood, such as Lygeum spartum, a fast-growing Mediterranean plant, is crucial. It has not been previously investigated as a potential source of nanocellulose. This study investigates the extraction of novel cellulose micro/nanofibers from Lygeum spartum using a two-step method, including both alkali and mechanical treatment as post-treatment with ultrasound, as well as homogenization using water and dilute alkali solution as a solvent. To determine the structural properties of CNFs, a series of characterization techniques was applied. A significant correlation was observed between the Fourier transform infrared (FTIR) spectroscopy and X-ray diffraction (XRD) results. The FTIR results revealed the elimination of amorphous regions and an increase in the energy of the H-bonding modes, while the XRD results showed that the crystal structure of micro/nanofibers was preserved during the process. In addition, they indicated an increase in the crystallinity index obtained with both methods (deconvolution and Segal). Thermal analysis based on thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) confirmed improvement in the thermal properties of the isolated micro/nanofibers. The temperatures of maximum degradation were 335 °C and 347 °C. Morphological analysis using a scanning electron microscope (SEM) and atomic force microscope (AFM) showed the formation of fibers along the axis, with rough and porous surfaces. The findings indicate the potential of Lygeum spartum as a source for producing high-quality micro/nanofibers. A future direction of study is to use the cellulose micro/nanofibers as additives in recycled paper and to evaluate the mechanical properties of the paper sheets, as well as investigate their use in smart paper. [ABSTRACT FROM AUTHOR]

Starting from the seminal works of Toupin, Mindlin and Germain, a wide class of generalized elastic models have been proposed via the principle of virtual work, by postulating expressions of the elastic energy enriched by additional kinematic descriptors or by higher gradients of the placement. More recently, such models have been adopted to describe phenomena which are not consistent with the Cauchy-Born continuum, namely the size dependence of apparent elastic moduli observed for micro and nano-objects, wave dispersion, optical modes and band gaps in the dynamics of heterogeneous media. For those structures the mechanical response is affected by surface effects which are predominant with respect to the bulk, and the scale of the external actions interferes with the characteristic size of the heterogeneities. Generalized continua are very often referred to as media with microstructure although a rigorous deduction is lacking between the specific microstructural features and the constitutive equations. While in the forward modelling predictions of the observations are provided, the actual observations at multiple scales can be used inversely to integrate some lack of information about the model. In this review paper, generalized continua are investigated from the standpoint of inverse problems, focusing onto three topics, tightly connected and located at the border between multiscale modelling and the experimental assessment, namely: (i) parameter identification of generalized elastic models, including asymptotic methods and homogenization strategies; (ii) design of non-conventional tests, possibly integrated with full field measurements and advanced modelling; (iii) the synthesis of meta-materials, namely the identification of the microstructures which fit a target behaviour at the macroscale. The scientific literature on generalized elastic media, with the focus on the higher gradient models, is fathomed in search of questions and methods which are typical of inverse problems theory and issues related to parameter estimation, providing hints and perspectives for future research. [ABSTRACT FROM AUTHOR]

Over the past decade, nanocomposites with polymer matrices have garnered significant attention for their ability to enhance properties with minimal inclusion volume, thanks to nanoscale reinforcement. The key factor distinguishing them from microcomposites is the interphase, an area of interaction where matrix properties are influenced by the reinforcement. This induces a dependence on particle size that sets nanocomposites apart. Observation of the interphase is achieved through experimental methods like atomic force microscopy (AFM) and numerical approaches such as molecular dynamics (MD) modeling. Indirect determination involves the comparison of experimental results with predictive models, which may be numerical or analytical homogenization schemes. The widely used double inclusion scheme focuses on nanocomposites, but for a comprehensive mechanical behavior prediction, elastic behavior alone is not sufficient. Factors in the matrix (plasticity, viscosity, temperature) and morphology (dispersion, surface treatment, bonding) must be considered. This review explores various methods in the literature that address these aspects. [ABSTRACT FROM AUTHOR]

This paper deals with the periodic unfolding for sequences defined on one dimensional lattices in R N . In order to transfer the known results of the periodic unfolding in R N to lattices, the investigation of functions defined as interpolation on lattice nodes play the main role. The asymptotic behavior for sequences defined on periodic lattices with information until the first and until the second order derivatives are shown. In the end, a direct application of the results is given by homogenizing a 4th order Dirichlet problem defined on a periodic lattice. [ABSTRACT FROM AUTHOR]

Keywords: Attractors; homogenization; reaction-diffusion system; nonlinear equations; weak convergence; randomly perforated domains; random porous medium; topological space; compactness.GraphBy Kuanysh A. Bekmaganbetov; Gregory A. Chechkin and Vladimir V. ChepyzhovReported by Author; Author; Author [Extracted from the article]

We investigate the homogenization of second-order elliptic systems with singular fourth-order perturbations in a perforated domain, in which the holes are distributed periodically with period $ \varepsilon $ throughout a bounded domain $ \Omega $ in $ \mathbb{R}^{d} $. The asymptotic behaviour of solutions and convergence rates, which depend on the scale $ \varepsilon^\alpha $ that represents the strength of the singular perturbations and on the length scale $ \varepsilon $ of the heterogeneities, are obtained. [ABSTRACT FROM AUTHOR]

Herein, an improved mechanical metamaterial is proposed, which is derived from the decomposition, rotation, and reassembly of reentrant structures. The structure is parametric, allowing for rapid redesign. The study focuses on the variations in equivalent stiffness and Poisson's ratio of the structure within the linear elastic range when internal rib angle θ changes. First, based on homogenization simulation analyses, it has been verified that this design achieves the tailorable equivalent elastic modulus and Poisson's ratio over a wide range, meanwhile, maintaining equal elastic properties in the orthogonal direction at all times. Second, to reduce future repetitive experiments, an interpolation model is established to expand the design domain. The fitting formula indicates that by modifying θ and relative wall thickness t/L0, the elastic performance of the structures can be tailored. Additionally, the impact of boundary conditions is discussed to minimize experimental costs. Finally, the accuracy of the simulations is validated through uniaxial compression tests. [ABSTRACT FROM AUTHOR]

AbstractThe lattice structure has great application prospects in the field of energy absorption, but the high cost of numerical analysis makes it difficult to carry out related structural designs. Therefore, this article studies the feasibility of the homogenization analysis technique for the analysis of energy absorption processes in lattice-filled structures. In the study, compression experiments and numerical simulations were conducted for four different types of unit cells (including periodic truss-lattice cells and triply periodic minimal surface (TPMS cells). In the experiments, two compression samples with different numbers of periods were designed for the same unit cell structure. The research shows that the homogenized numerical model takes a lot less time to run than the classical beam and shell element models. The results of the simulation are also in line with the data from the experiments. On the other hand, the material curve constructed based on a small number of unit cell samples has excellent analytical accuracy. This means that relevant research can obtain the material experimental data required for homogenized analysis using lattice samples with low manufacturing costs. Understanding these phenomena can provide a basis for the design of energy absorption structures. [ABSTRACT FROM AUTHOR]

ABSTRACT This study aims to evaluate homogenization techniques and conditions for producing stable, small droplet‐size water‐in‐oil (W/O) emulsions intended for incorporation into casein hydrolysate–loaded double emulsions. Three commonly used homogenization methods; rotor–stator, ultrasonic, and high‐pressure homogenization were individually optimized utilizing response surface methodology. Instances of over‐processing were observed, particularly with the rotor–stator and ultrasonic homogenizers under specific conditions. Nevertheless, optimal conditions were identified for each technique: 530 s at 17,800 rpm agitation speed for the rotor–stator homogenizer, 139 s at 39% amplitude for the ultrasonic homogenizer, and 520 s at 1475 bar for the high‐pressure homogenizer. Subsequently, the W/O emulsions produced under optimal conditions and their respective W1/O/W2 double emulsions were compared. The rotor–stator and high‐pressure homogenized W/O emulsions exhibited comparable narrow droplet‐size distributions, as indicated by similar Span values. However, high‐pressure homogenization failed to sufficiently minimize droplet size. Ultrasonic homogenization resulted in droplets at the 1‐μm scale but yielded more polydisperse droplet‐size distribution. According to TOPSIS analysis, an emulsion with a viscosity of 93.1 cP (centiPoise), a stability index of 93.8%, a D(90) of 0.67 μm (0th day), and a D(90) of 0.75 μm (30th day) produced using a rotor–stator was selected. Additionally, double emulsions containing primary emulsions prepared with the rotor–stator method demonstrated higher viscosity, narrower droplet‐size distribution, and lower creaming compared to other samples. This investigation sheds light on the influence of homogenization techniques on emulsion properties, providing valuable insights for optimizing double emulsion formulations. [ABSTRACT FROM AUTHOR]

The expansion of northern Pike Esox lucius outside its native range into the western states of North America is a growing problem due to their negative effects on fish communities. Illegally introduced E. lucius were first detected in Box Canyon Reservoir in northeast Washington in 2004. By 2010, the E. lucius population was estimated at more than 10,000 individuals. Between 2012 and 2019, a gillnet suppression programme was conducted, which reduced the E. lucius catch per unit effort in Box Canyon Reservoir by 97% and their biomass by 98%. Between 2004 and 2019, four standardized surveys were conducted to characterize changes in the Box Canyon Reservoir fish community. Even after E. lucius were effectively suppressed, native species showed no signs of recovery during the study. The relative abundance of all native species decreased 82% in total number and 56% in total biomass between 2004 and 2019. Conversely, the relative abundance of non‐native species increased 26% in total number and 33% in total biomass over the same period. As an apex predator, E. lucius had a significant impact on the fish community in Box Canyon Reservoir over a relatively short period of time (7 years), and appeared to act as a catalyst to increase the rate of replacement of native species with non‐native species, which likely increased the pace of taxonomic homogenization in the reservoir. [ABSTRACT FROM AUTHOR]

The distorted spots induced by atmospheric turbulence significantly degrade the spot position detection accuracy of the quadrant detector (QD). In this paper, we utilize angular measurement and homogenization characteristics of non-imaging microlens array (NI-MLA) systems, effectively reducing the distortion degree of the spots received on the QD target surface, thereby significantly enhancing the spot detection accuracy of the QD. First, based on the principles of geometric optics and Fourier optics, it is proved that the NI-MLA system possesses the angular measurement characteristic (AMC) within the paraxial region while deriving and verifying the focal length of the system. Then, the QD computation curve characteristics of the system under non-turbulence are explored. This study further elucidates the mathematical principle of the NI-MLA system for mitigating the spot position detection random error of QD (SPDRE-QD) and discusses in depth the relationship between the NI-MLA system's capability to mitigate the SPDRE-QD and the system's parameters under various turbulence intensities. Finally, it is experimentally verified that the root-mean-square error (RMSE) of the QD computation values using the NI-MLA system are reduced by a significant improvement of at least 2.44 times and up to 17.36 times compared with that of the conventional optical system of QD (COS-QD) under turbulence conditions ranging from weak to strong. [ABSTRACT FROM AUTHOR]

In this work we develop a homogenization methodology to upscale mathematical descriptions of microcirculatory blood flow from the microscale (where individual vessels are resolved) to the macroscopic (or tissue) scale. Due to the assumed two-phase nature of blood and specific features of red blood cells (RBCs), mathematical models for blood flow in the microcirculation are highly nonlinear, coupling the flow and RBC concentrations (haematocrit). In contrast to previous works which accomplished blood-flow homogenization by assuming that the haematocrit level remains constant, here we allow for spatial heterogeneity in the haematocrit concentration and thus begin with a nonlinear microscale model. We simplify the analysis by considering the limit of small haematocrit heterogeneity which prevails when variations in haematocrit concentration between neighboring vessels are small. Homogenization results in a system of coupled, nonlinear partial differential equations describing the flow and haematocrit transport at the macroscale, in which a nonlinear Darcy-type model relates the flow and pressure gradient via a haematocrit-dependent permeability tensor. During the analysis we obtain further that haematocrit transport at the macroscale is governed by a purely advective equation. Applying the theory to particular examples of two- and three-dimensional geometries of periodic networks, we calculate the effective permeability tensor associated with blood flow in these vascular networks. We demonstrate how the statistical distribution of vessel lengths and diameters, together with the average haematocrit level, affect the statistical properties of the macroscopic permeability tensor. These data can be used to simulate blood flow and haematocrit transport at the macroscale. [ABSTRACT FROM AUTHOR]

An initial boundary value problem for the in situ leaching is considered. We describe physical processes at the microscopic level with a pore size e « 1 by model Ae, where dynamics of the incompressible solid skeleton is described by the Lamé equations and the physical process in the pore space by the Stokes equations for the incompressible fluid with diffusion equations for the concentration of acid and product of chemical reactions. Since the solid skeleton changes its geometry upon dissolution, the "pore space - solid skeleton" boundary is a free boundary. The goal of the present manuscript is a model H, which is the homogenization of the model Ae. That is, the limit as e tend to zero, of the model Ae. As usual, free boundary problems are only solvable locally in time. On the other hand, in situ leaching has a very long process duration and there is still no correct microscopic model that describes this process for an arbitrary time interval. To avoid this contradiction, we propose correct approximate microscopic models Be(r) for this process with a given solid skeleton structure depending on some function r from the set M(0,T). Problem Be(r) is the model Ae without an additional boundary condition at the free boundary that defines this boundary, but with some additional terms in the Stokes and Lame equations that depend linearly on the velocities and disappear upon homogenization. To derive a macroscopic mathematical model H(r) and separately the additional boundary condition at free boundary we use Nguenseng's two-scale convergence method as e tends to zero. As a result, we obtain a homogenized model H(r) and an additional equation, possesses construct an operator, which fixed point uniquely defines function r * from the set M(0,T) and prove the existence and uniqueness theorem for the macroscopic mathematical model H. [ABSTRACT FROM AUTHOR]

Several studies have demonstrated potential of cellulose nanofibers (CNF) in various applications. However, no protocols are available for the production of spray-dried CNF with high water redispersibility; interfibrillar hydrogen bonding that occurs during spray drying is believed to be responsible for such lack of redispersibility. The present study therefore aimed to develop a protocol that can be used to prepare CNF powders from Centella asiatica via spray drying, with maltodextrin (MD) at CNF-to-MD ratios of 1:0, 1:1, 1:1.5, 1:2 and 1:2.5 as the drying aid. Chlorophylls within such plant were also complexed with zinc in order to allow the resulting redispersed CNF to exhibit thermally stable green color. The resulting powders were analyzed for their morphology, XRD pattern and FTIR spectra to confirm the interaction between CNF and MD. Appropriate CNF-to-MD ratios were determined based on the sedimentation behavior, morphology, fiber sizes and viscoelasticity of the redispersed suspensions. Only spray-dried powders with CNF-to-MD ratios of 1:2 and 1:2.5 showed no sedimentation during the entire storage period. Suspensions prepared from the powders produced at these ratios were also capable of regaining morphology and nanofibrous widths (19–20 nm) comparable to those of freshly prepared CNF suspension, with gel-like behavior and viscoelasticity remained unchanged. Zinc-chlorophylls complex possessed thermal stability under the employed spray drying condition, as confirmed by the retention of chlorophylls in the powders. Green color of redispersed CNF suspensions was similar to that of freshly prepared CNF suspension. [ABSTRACT FROM AUTHOR]

In this work, we present a new two-scale finite-strain plate theory for highly heterogeneous plates described by a repetitive periodic microstructure. Two scales exist, the macroscopic scale is linked to the entire plate and the microscopic one is linked to the size of the heterogeneity. This work aims to propose such a theory for thick plates in a nonlinear setting when the thickness and the size of heterogeneities are of the same order of magnitude. The homogenization theory for large deformation with growth is suitable for the modelization of nearly incompressible plant tissue. This model is suitable for wavy leaves. For thick plates, the transverse normal stress and transverse shearing are modelized at both microscopic and macroscopic levels. At the macroscopic level, we consider a nonlinear Cosserat plate model. At the microscopic level, we impose that the average of contribution of the microscopic displacement to rotation angles is equal to zero. We also deal with the problem of boundary layer problem near the lateral boundary. The model recently proposed by Pruchnicki is valid for thin heterogeneous plates; we present an extension for thick plates that takes into account both transverse normal stress and shearing. This model is equivalent to the first model presented but it involves a second-order derivative of the macroscopic displacement field. [ABSTRACT FROM AUTHOR]

Predicting the physical property of a class of microstructures is crucial in material design, structural simulation, and design. Property prediction may be conducted millions of times in these studies and is better derived instantly for computational efficiency. This issue is addressed in this study via building a mapping from a 3D microstructure to its effective material property, or called structure–property mapping, using a 3D convolutional neural network (CNN). Unlike the direct approach using labeled simulation data, the mapping is based on the physical knowledge of the structure–property relationship determined by its underlying PDE equations. The knowledge is embedded in the loss function of the CNN framework, which is designed and tested under several different formulations to improve its training convergence. Ultimately, the derived structure–property mapping can instantly predict the associated material property for a given microstructure and has far better generalization ability than the data-labeled approach, as demonstrated via numerical examples. [ABSTRACT FROM AUTHOR]

We propose a homogenized supremal functional rigorously derived via L p -approximation by functionals of the type ess-sup x ∈ Ω f (x , D u) , when Ω is a bounded open set of ℝ n and u ∈ W 1 , ∞ (Ω ; ℝ d). The homogenized functional is also deduced directly in the case where the sublevel sets of f (x , ⋅) satisfy suitable convexity properties, as a corollary of homogenization results dealing with pointwise gradient constrained integral functionals. [ABSTRACT FROM AUTHOR]

The elastic properties of dilute solid suspensions with imperfectly bonded inclusions of ellipsoidal shape are estimated. The imperfect bonding is regarded as a sharp interface across which the displacement jumps in proportion to the surface traction. Elastic compliances of the matrix and inclusion phases can exhibit arbitrary anisotropy while that of the bonding exhibits an anisotropy that depends on the interface normal only. A variational framework is employed to generate pairs of elementary bounds, asymptotically exact results, and approximations for the effective elasticity tensor. Each member of the pair differs in the way the bonding compliance is averaged over the interfacial surface: an 'arithmetic' mean in one case and a 'harmonic' mean in the other case. The results are used to infer the most convenient approximation for a given range of material parameters. [ABSTRACT FROM AUTHOR]

We study the effective properties of a linear elastic or perfectly viscoplastic composite consisting of a soft matrix reinforced by possibly very stiff fibers. The effective material is characterized by the emergence of a discrepancy between the displacement in the fibers and the overall averaged displacement, giving rise to a concentration strain in the matrix. The effective energy stored in the fibers is a combination of stretching, bending and torsional energies. This work completes and corrects results previously obtained by the author and coworkers, who failed to notice the torsional contribution. [ABSTRACT FROM AUTHOR]

A multi-scale framework is constructed for the computation of the stiffness tensors of an elastic strain-gradient continuum endowed with an anisotropic microstructure of arbitrarily-shaped particles. The influence of microstructural features on the macroscopic stiffness tensors is demonstrated by comparing the fourth-order, fifth-order and sixth-order stiffness tensors obtained from macro-scale symmetry considerations to the stiffness tensors deduced from homogenizing the elastic response of the granular microstructure. Special attention is paid to systematically relating the particle properties to the probability density function describing their directional distribution, which allows to explicitly connect the level of anisotropy of the particle assembly to local variations in particle stiffness and morphology. The applicability of the multi-scale framework is exemplified by computing the stiffness tensors for various anisotropic granular media composed of equal-sized spheres. The number of independent coefficients of the homogenized stiffness tensors appears to be determined by the number of independent microstructural parameters, which is equal to, or less than, the number of independent stiffness coefficients following from macro-scale symmetry considerations. Since the modelling framework has a general character, it can be applied to different higher-order granular continua and arbitrary types of material anisotropy. [ABSTRACT FROM AUTHOR]

Pea proteins have garnered attention as a viable alternative to animal proteins, offering health, and sustainability benefits. However, their functional limitations, such as poor solubility, hinder their application in plant‐based food products. This review details the specific physical, chemical, and biological methods employed to enhance pea protein functionality. Chemical methods have been the most effective, particularly in improving solubility, emulsification, and foaming properties, which are essential for food applications like dairy alternatives and meat analogues. Biological methods significantly enhance water and oil retention, contributing to better food texture. Physical methods, including ultrasound and heat treatment, also show promise but require careful application to avoid protein denaturation. While chemical methods are efficacious, they raise concerns about cost‐effectiveness and environmental impact. The review identifies combined treatment approaches as a fertile area for future research, suggesting that a multi‐faceted strategy may provide comprehensive improvements to pea protein functionality. [ABSTRACT FROM AUTHOR]

In this paper, we study the asymptotic behaviour of solutions of a coupled system of partial differential equations in a thin domain with oscillating boundary and varying order of thickness. In such a thin domain, our model describes the solute concentration of two different biochemical species (metabolites). The coupling between the concentrations of the metabolites is realized through reaction terms even nonlinear, appearing on the oscillating upper wall. Moreover nonlinear reaction terms appear also in the thin domain. The reaction catalyzed by the upper wall is simulated by a Robin-type boundary condition depending on a small parameter ε . Hence, taking into account that α > 1 and β > 0 , we analyze the coupled system by comparing the magnitude of the reaction coefficient ε β on the upper boundary with the compression order of our thin domain, which can be ε or ε α , depending on the sub-regions with different order of thickness. Comparing the exponents 1, α and β , we obtain different cases for the limit problem which could appear coupled or uncoupled and allow us to identify the effects of the geometry and the physical process on the problem. Moreover it arises a critical value, i.e. β = α - 2 , leading the reaction effects entering in the diffusion matrix. [ABSTRACT FROM AUTHOR]

This study focuses on determining the optimum external operating parameters of algal cell lysis for extraction of bio-oil from Chlorella biomass. Response surface methodology has been applied to a regression analysis model for optimizing solvent ratios, i.e., ethyl acetate to ethanol (E.A.:E) ratio for maximum extraction of bio-oil and aqueous deep eutectic solvent to biomass (aDES:biomass) ratio for algal pretreatment for the enhanced yield of bio-oil. Optimized process conditions were 15 min of homogenization combined with ultrasonication (hybrid method). The aDES:biomass ratio of 8.25 caused the highest cell disruption efficiency to liberate bio-oil from encapsulated cells. The solvent ethyl acetate to ethanol ratio (E.A.:E) was optimum at 0.8 for maximum extraction of bio-oil, and studies indicated a maximum bio-oil yield of 94.0% using this hybrid pretreatment process combined with ultrasonication and homogenization. The GC–MS characterization technique was used to analyze the bio-oil, which showed it consisted of 67.93% Di-ethyl phthalate (DEP) and 32.07% esters compounds (C12–C40 hydrocarbons range). The produced DEP from Chlorella biomass using this sustainable green approach is very promising. The estimated cost was around Rs 49 per gm (equivalent to Rs 664.56 for 13.58 gm), which indicates the potential for a cost-effective method to produce pure DEP from Chlorella biomass. [ABSTRACT FROM AUTHOR]

A reduced-order homogenization framework is proposed, providing a macro-scale-enriched continuum model for locally resonant acoustic metamaterials operating in the subwavelength regime, for both time and frequency domain analyses. The homogenized continuum has a non-standard constitutive model, capturing a metamaterial behaviour such as negative effective bulk modulus, negative effective density and Willis coupling. A suitable reduced space is constructed based on the unit cell response in a steady-state regime and the local resonance regime. A frequency domain numerical example demonstrates the efficiency and suitability of the proposed framework. This article is part of the theme issue 'Current developments in elastic and acoustic metamaterials science (Part 2)'. [ABSTRACT FROM AUTHOR]

Three-dimensional metamaterials endowed with two-dimensional in-plane periodicity exhibit peculiar thermoelastic behaviour when heated or cooled. By proper design of the unit cell, the equivalent thermal expansion coefficient can be programmed and can also reach negative values. The heterogeneity in the third direction of such metamaterials also causes, in general, a thermal-induced deflection. The prediction of the equivalent thermal properties is important to design the metamaterial suitable for a specific application. Under the hypothesis of small thickness with respect to the global in-plane dimensions, we make use of asymptotic homogenization to describe the thermoelastic behaviour of these metamaterials as that of an equivalent homogenous plate. The method provides explicit expressions for the effective thermal properties, which allow for a cost-effective prediction of the thermoelastic response of these metaplates. [ABSTRACT FROM AUTHOR]

The technology of manufacturing aluminum alloy workpieces using additive friction stir deposition (AFS‐D) has been thoroughly investigated. The ambiguous influence of deformation processing modes on the material density was found. Examination of the microstructure in the central zone of the specimens reveals the absence of microdefects typically associated with workpieces obtained through casting or powder metallurgy methods. It has been observed that the distribution of microhardness is significantly affected by the direction of specimen construction, with approximately a 20% difference in values between the periphery and the central part of the specimen. Specimens produced using the AFS‐D method exhibit a homogeneous microstructure characteristic of deformable aluminum alloys. Notably, a uniform distribution of intermetallides on the specimen surface has been identified. This outcome is likely a result of the alloy undergoing recrystallization during the severe plastic deformation process, leading to the formation of an ultradisperse structure. It is important to emphasize that the selection of technological parameters for AFS‐D should consider not only the magnitude of pressure and deformation but also the deformation speed. [ABSTRACT FROM AUTHOR]

We present an efficient approach to evaluate the size dependency of elastic and plastic properties of metallic polycrystalline materials. Specifically, we consider different volume fractions of ferrite and martensite phases for the construction of three macroscopic domains. Statistical Volume Elements (SVEs) of different sizes are extracted from these domains using the moving window method. Linear and Crystal Plasticity (CP) simulations provide elastic and plastic properties of the SVEs such as the bulk and shear moduli, yield strength, and hardening modulus. We use a variation-based criterion to determine the Representative Volume Element (RVE) size of these properties. This RVE size corresponds to a size beyond which the given property can be idealized as homogeneous. We also use anisotropy indices and an additional RVE size criterion to determine the size limits beyond which these properties can be idealized as isotropic. Numerical results show that the plastic properties often reach their homogeneity and isotropy limits at larger sizes compared to elastic properties. This effect is more pronounced for the hardening modulus compared to the yield strength. [ABSTRACT FROM AUTHOR]

A theoretical model is used to study water waves propagating into and through a region containing thin floating ice, for ice covers transitioning from consolidated (large floe sizes) to fully broken (small floe sizes). The degree of breaking is simulated by a mean floe length. The model predicts deterministic limits for consolidated and fully broken ice covers where the wave fields do not depend on the particular realization of the ice cover for a given mean floe length. The consolidated ice limit is consistent with classic flexural-gravity wave theory, and the fully broken limit is well-modelled by Bloch waves in a periodic ice cover. In the transition between the limits, the wave field depends on the ice cover realization, as multiple wave scattering is a dominant process. The effects of the ice cover on the wave field are quantified using a wavelength, an attenuation rate and a transferred amplitude (measuring the amplitude drop at the ice edge). The model predicts that as the ice cover breaks up (mean floe size gets smaller), the wavelength and amplitude drop decrease (transferred amplitude increases) and the attenuation rate increases. The results provide an interpretation of field observations. [ABSTRACT FROM AUTHOR]

Captured by relatively low energy consumption and harmful gas‐emission, direct regeneration has captured numerous attention, but still suffers from different particle sizes and diverse doping hetero‐elements, hardly meeting the market demand. Herein, assisted by the crush‐sinter regeneration from element to grain further to particle, homogenized recovery of hetero spent LiCoO2 is successfully carried out. More interestingly, after tailoring Li/Co anti‐sites ratio, the redox activity of Co‐ions is remarkably enhanced, effectively inhibiting the irreversible escape of O‐atoms under high voltage, bringing about the fascinating electrochemical performance and structural stability. As anticipated, the regenerated LiCoO2 delivered a considerable capacity of 175.2 mAh g−1 at 1.0 C, whilst its capacity retention can remain at 88.86% even after 500 cycles at 5.0 C, better than that of commercial materials. Assembling regenerated materials versus. graphite pouch cell, their considerable practical capacity retention can be kept at ≈91.4% even after 500 cycles. Supported by in situ XRD, electronic structure analysis, and detailed DFT calculations, the excellent high voltage stability of optimized samples mainly comes from the alleviating of phase conversion and oxygen redox. This work is expected to shed light on the potential value of homogenized regenerations, and offer effective strategies of upcycling about spent LCO. [ABSTRACT FROM AUTHOR]

BACKGROUND RESULT CONCLUSION Plant‐based beverages have recently seen a significant increase in market demand. However, many of these products suffer from poor emulsion stability and low protein content. Gums have commonly been used to enhance emulsion stability but they do not improve the amino acid profile. This study investigated the use of multiples plant proteins to enhance both the stability and nutritional value of plant‐based beverages.Pea and rice bran proteins both enhanced emulsion stability. Pea protein enhanced the viscosity of the continuous phase whereas rice bran protein lowered interfacial tension. When applied synergistically, competitive adhesion occurred. Rice bran protein gradually displaced pea protein from the oil droplet surface as its concentration increased, leading to emulsion destabilization due to the displaced pea protein. The use of high‐pressure homogenization further enhanced the stability of the emulsion by unfolding protein partially. However, increasing homogenization pressure (>500 Bar) and homogenization cycle (>2 cycles) led to protein aggregation due to excessive exposure of its hydrophobic core. The emulsion formed was resistant to coalescence at 4 °C for 28 days and was stable under high pH and low ionic conditions.The synergistic combination of plant proteins and the effective utilization of co‐processing (homogenization) can enhance the functionality of the individual proteins significantly, leading to the formation of a stable emulsion. The use of plant protein mixture as a stabilizer not only improved the emulsion stability but also ensured a plant‐based beverage with a complete amino acid profile for the vegan community. © 2024 The Author(s). Journal of the Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

In this article we study the homogenization and uniform decay rates estimates of the energy associated to the damped nonlinear wave equation ∂ t t u ε − Δ u ε + f (u ε) + a (x) g (∂ t u ε) = 0 in Ω ε × (0 , ∞) where Ω ε is a domain containing holes with small capacity (i.e. the holes are smaller than a critical size). The homogenization's proofs are based on the abstract framework introduced by Cioranescu and Murat [14] for the study of homogenization of elliptic problems. The main goal of this article is to prove, in one shot, uniform decay rate estimates of the energy associated to solutions of the problem posed in the perforated domain Ω ε as well as for the limit case Ω when ε → 0 by using refined arguments of microlocal analysis. [ABSTRACT FROM AUTHOR]

This paper is devoted to studying the null internal controllability of a Kirchoff--Love thin plate with a middle surface having a comb-like shaped structure with a large number of thin fingers described by a small positive parameter ε. It is often impossible to directly approach such a problem numerically, due to the large number of thin fingers. So an asymptotic analysis is needed. In this paper, we first prove that the problem is null controllable at each level ε. We then prove that the sequence of the respective controls with minimal L² norm converges, as ε vanishes, to a limit control function ensuring the optimal null controllability of a degenerate limit problem set in a domain without fingers. [ABSTRACT FROM AUTHOR]

This paper presents a numerical study of the influence of geometry and orientation of fibres on the mechanical behaviour of a hemp fibre reinforced polypropylene, obtained with injection. Tensile tests and multiplexing mode Dynamic Mechanical Analysis (DMA) were carried out in order to determine the mechanical behaviour of the neat and reinforced material. A numerical homogenization was then performed with the elastic hemp fibres for aligned and random orientation as well as a reconstructed microstructure obtained with injection simulation to correlate with tensile tests. The simulations were performed for sphero-cylinder and curved fibres and the results were compared to FFT results obtained directly on micro-tomography images as well as experimental data. The results showed that the complex geometry of the fibres can be approximated with a random 3D orientation of sphero-cylinder shaped fibres, a reasonable hypothesis leading to a simplification of the problem and an easier process of design of parts made with such materials. [ABSTRACT FROM AUTHOR]

Thermal and mechanical treatments may affect the structure of hydrolyzed proteins, thus influencing the obtaining of peptides with improved bioactivity. In this work, tilapia muscle was treated by thermal sterilization or homogenization with ultra‐turrax (UT) and hydrolyzed with alcalase to obtain FPHs with antioxidant properties in salad dressing. To evaluate the bioactive potential of FPHs, the acetylcholinesterase inhibition assay was applied, resulting in up to 45.87% inhibition for the UT sample (60 mg/mL). Also, no cytotoxicity was detected by Allium cepa model for all FPHs. The emulsifying activity index and emulsifying stability index of FPHs indicated better emulsifying capacity in basic pH. As a proof of concept, FPHs were used as an emulsifying/antioxidant agent to prepare a salad dressing. FPHs increased the formulation's protein content, pseudoplastic behavior, color, and texture. In addition, FPHs aided the oxidative stability of salad dressing (evaluated by oil's extinction coefficient), demonstrating potential application in emulsified foods by acting on the elimination of radicals generated in lipid oxidation. Practical applications: Fish protein hydrolysates (FPHs) offer diverse bioactive properties such as antioxidant, antimicrobial, anticancer, antihypertensive, and acetylcholinesterase (associated with Alzheimer's disease) inhibitory effects. However, optimizing their technological properties poses a challenge, affecting applicability and bioactivity. Industrial processes such as thermal and mechanical treatments can alter protein structures, influencing peptide bioactivity post enzymatic hydrolysis. This study investigates the impact of substrate pre‐treatments, sterilization via thermal heating, and homogenization using a rotor‐stator system (ultra‐turrax) on FPHs' technological properties after hydrolysis with alcalase, including emulsifying capacity and acetylcholinesterase inhibitory capacity. In addition, it explores the application of pre‐treated FPHs in a real food system (French salad dressing), assessing rheological properties, texture, and oxidative stability. Such evaluations are crucial for ensuring the feasibility of industrial FPHs production and their application. [ABSTRACT FROM AUTHOR]

The purpose of the work is to study by experimental analysis and finite element methods the mechanical response of a packaging, consisting of a corrugated cardboard container, used for the transport of fruit and vegetables. During the container design, three different configurations were selected which differ both in the choice of liner and in the type of wave. In particular, the type E, F and N microwaves were chosen. They are characterized by a lower amplitude than the high and medium waves commonly used in corrugated cardboard packaging, making it possible to reduce material consumption and, consequently, costs. In the initial phase of the study, experimental tests were performed to evaluate the mechanical strength of the liners. In addition, edge compression tests (ECTs) were performed to determine the stacking resistance of the structure. The break‐in resistance of the structures was analysed using a test conducted according to an internal standard, called strength packaging test (SPT). Subsequently, a parametric study was set up with the finite element method for the simulation of the mechanical behaviour of the three structures, using the homogenization technique. The comparison between the maximum total deformations, measured experimentally and calculated numerically, has highlighted the need to introduce corrective coefficients to improve the homogenization of the wave structure. In this way, it was possible to improve the matching of the results obtained on the structures simulated by the homogenization technique and those obtained on the corresponding real structures. [ABSTRACT FROM AUTHOR]

AA 7068 Aluminum alloy is produced via conventional solidification (CS) and controlled diffusion solidification (CDS) processing and homogenized at 450 °C for 6 and 12 h. Optical microscopy (OM) and scanning electron microscopy (SEM) equipped with an energy dispersive x-ray spectroscope (EDS) were used to examine the as-cast and homogenized samples. It was found that although the CS sample is more chemically homogenized in the as-solidified state, the CDS sample exhibits a higher homogenization rate during the treatment. The calculated phase diagram (CALPHAD) methodology was employed to study the effect of silicon and iron on the solidification path and homogenization of the alloy. Silicon consumes magnesium atoms on the surface of the α-Al phase to form the Mg2Si phase. Therefore, the magnesium concentration on the α-Al phase required for the formation of the σ phase must be increased. Calculations shows that all the Mg atoms at this stage are completely supplied from the bulk of the αAl phase. It can be hypothesized that during the last stage of solidification, a solid/liquid diffusion couple can be created between the primary αAl and the remaining liquid for several minutes (4 min at a cooling rate of 0.2 oC/s). As a result of the activation of this couple, the Mg atoms diffuse from the α-Al bulk to its surface, and vacancies diffuse from the surface to the bulk, forming a line of Kirkendall voids. With CDS processing, the surface of the primary phase is less Mg-concentrated than that in the CS process and this significantly reduces the formation of the Mg2Si phase. Conversely, the vacancy and Mg concentration of the αAl phase in CDS is higher than that of CS and this lets other alloying elements other than Mg diffuse to the primary phase, decreasing the homogenization time. The presence of Si in the alloy leads to the formation of the Mg2Si phase, which significantly reduces the final Mg concentration in the α-Al phase after full homogenization. In the pure alloy, the Mg concentration is 2.42 wt%, while in the FeSi-containing alloy, it is reduced to 1.58 wt% due to solid solution and dispersion strengthening mechanisms. Through CDS processing, the negative impact of Si can be reduced by disrupting the mechanism of Mg2Si formation.

Abstract The objective of this study was to assess the impact of incorporating Saccharomyces boulardii yeast (a known probiotic culture) as an adjunct culture on the quality characteristics of Mozzarella cheese, prepared using two different cheesemaking protocols. Protocol I employed unhomogenized milk with cheddaring prior to plasticizing (CUMC), while Protocol II used a blend of homogenized and unhomogenized milk (1:1; BHMC) and obviating cheddaring step. A control cheese (UMC) was produced from unhomogenized milk. The study aimed to determine which cheesemaking protocol better supports S. boulardii survival and produces sensorily satisfactory cheese quality. Key findings showed that cheese made with Protocol II, particularly BHMC4.2 with a higher level of yeast, exhibited the highest yield. Textural properties of cheeses CUMC and BHMC were similar, with UMC and CUMC cheeses demonstrating superior baking characteristics such as shredding, melting, and controlled fat leakage. Sensory evaluation indicated that cheese made with a lower level of adjunct culture scored higher during pizza applications. Furthermore, higher adjunct yeast level produced cheeses having increased S. boulardii as well as Lactic Acid Bacteria counts. The study recommends using cheesemaking Protocol II, as it fosters a S. boulardii count of ~ 105 CFU/g through use of milder cheese curd plasticizing conditions, enhancing the survival of the probiotic yeast. These findings have practical implications for production of Mozzarella cheese having viable probiotic yeast count.

High-strength Al alloys of the 7xxx series are promising candidates for further light-weighting of car bodies. However, they are difficult to process by extrusion: complex geometries in particular pose a major challenge due to high extrusion pressures and tool wear. In addition to process optimization, alloy chemistries can be tailored for properties such as good extrudability or high strength. In this work, several experimental alloys based on EN AW 7108A were investigated with respect to the contents of the main alloying elements Zn and Mg, as well as heat treatment (e.g., homogenization), to achieve good extrudability and favourable mechanical properties. The experimental alloys were initially extruded on a small-scale extrusion press and evaluated with regards to their warm formability, microstructure, extrudability, and mechanical properties in T5 temper. Alloy compositions with Mg contents

Two issues arise in the calculation of the multi-group scattering matrix when employing a continuous-energy Monte Carlo code for generating homogenized multi-group cross-sections. Firstly, the analog estimator is used to evaluate group-to-group elements, which leads to large statistical uncertainty. Secondly, employing the scalar flux as the weighting function in generating the high-order scattering matrix introduces errors in fast reactor calculations. For the first issue, the repeated collision approach and pre-tabulated cross-section approach are adopted to improve the tally efficiency. For the second issue, the average scattering cosine is calculated based on the conservation of the mean square displacement of neutrons, which is then used to correct the first-order self-scattering cross-section. To evaluate the effectiveness of the above approaches, a PWR pin-cell problem and fast reactor core problems are tested. The results demonstrate that: 1) The figure of merit for multi-group scattering matrix calculations was improved by 8–12 times with the pre-tabulated cross-section approach. 2) Biases of keff were reduced from over 500 pcm to less than 300 pcm when using the corrected self-scattering cross-section. 3) The corrected self-scattering cross-section also yielded higher accuracy for the assembly power calculations, where the maximum biases are reduced from 5 % to 1 %.

This work presents a homogenization damage approach for brittle composites based on the concept of Representative Volume Element (RVE) performing complex numerical analysis of the mechanical behavior of materials with individual characteristics of constituent phases. Focusing on concrete material, cement paste and transition zone are modeled as damaged materials using the Mazars' model, while the aggregates are modeled as linear elastic material. A based homogenization damage model technique is obtained and it is applied to describe the damage in the macrostructure. Results for concrete microstructures are presented and the homogenized responses demonstrate the expected behavior, including comparison with experimental test. [ABSTRACT FROM AUTHOR]

In this paper, we study the homogenization of quasilinear elliptic problems with a jump on the interface between the two components proportional to the flux depending on a real parameter γ. The data is presumed to be an $ L^1 $ L 1 function and consequently, we consider the notion of renormalized solutions. In the homogenization process, we employ the periodic unfolding method. The homogenized problem was afterwards identified to be a quasilinear elliptic problem with $ L^1 $ L 1 data for the case that the parameter γ is between $ -1 $ − 1 and 1 and for the case where γ is less than $ -1 $ − 1. [ABSTRACT FROM AUTHOR]