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The field of negative stiffness structures has recently seen an increase in attention as a result of advancements in additive manufacturing (AM) technology. These advancements have made it possible to produce materials in a more expedient manner. The purpose of this research is to demonstrate a highly tunable and reusable bistable beam design that is based on a double-ring-shaped deformation element that undergoes pure bending, unlike traditional bistable mechanisms with buckling-based deformation elements. Further, an analytical model is developed and then validated by means of experimental and numerical results to precisely predict the snap-through behavior of a beam. It has been shown that the analytical model that was proposed has accuracy in terms of foreseeing the snap-through transition. A detailed study is conducted to explore the influence of geometric parameters on the snap-through characteristics. By carefully modifying these geometric properties, the required mechanical behavior of negative stiffness metamaterial (NSM) may be achieved for specific applications. [ABSTRACT FROM AUTHOR]

Space-coiling acoustic metamaterials dominated by the Fano resonance are being widely exploited for simultaneous control of sound isolation and air ventilation, and they usually achieve complete sound mitigation at multiple isolated frequencies. Here, we theoretically discover and experimentally demonstrate the low-transmission flat-band phenomenon in channeling-type acoustic metamaterials. The metamaterial is constructed with coupled coiling and straight channels, both working in acoustic resonant states. An analytic coupled-mode model is established to capture the coupling interaction between resonant states supported by two channels. A critical coupling condition is derived from the model, which can lead to sextremely low sound transmission in a finite band rather than at isolated frequencies, as validated by both numerical simulations and experiments. We then demonstrate the generality of the flat-band behavior of low transmission by a systematic survey of the coupling of different order resonant modes. Finally, the flat-band effect is also found to exist in the extended model with the side-loaded coiling channel as verified experimentally. [ABSTRACT FROM AUTHOR]

The primary goal of the current work is to investigate how wave propagation influences the performance of surface acoustics wave (SAW) macro- and nano-sensors. Therefore, shear horizontal (SH) waves use the surface piezoelectricity theory to explore SH waves in an orthotropic piezoelectric quasicrystal (PQC) layer overlying an elastic framework (Model I), a piezoelectric substrate, and an orthotropic PQC substrate (model II). This study employs a variable-separable technique. The theoretical forms are constructed and used to present the wavenumber of surface waves in any direction of the piezoelectric medium, based on the differential equations and matrix formulation. In addition, we take into account the surface elasticity theory in order to obtain the phase velocity equation. Two configurations are examined: an orthotropic piezoelectric material layer over an elastic framework and a piezoelectric material half-space with a nanosubstrate. Analytical expressions for frequency equations are derived for both symmetric and antisymmetric waves. This study investigates the effects of surface elastic constants, surface density, anisotropic piezoelectric constant, and symmetric and antisymmetric modes on phase velocity. This study is confined to only linear wave propagation. Additionally, the analysis is based on idealized material properties, surface properties, and characteristic length of the material. [ABSTRACT FROM AUTHOR]

Reaction of lanthanoid tris(3,5‐dimethylpyrazolate) compounds, [Ln(Me2pz)3(thf)]2 (Ln=La 1 a, Ce, Pr, Dy 1 b, Yb, Lu) with potassium or lithium bistrimethylsilylamide and with or without added 3,5‐dimethylpyrazole, or of lanthanoid tris(bistrimethylsilyl)amide complexes with potassium bistrimethylsilylamide and 3,5‐dimethylpyrazole have yielded a variety of oxide centred Ln3 or Ln4/(K or Li)1–3 multinuclear cages, namely, [La4O(Me2pz)11 K(thf)2] (2 a), [La4O(Me2pz)11Li(Me2pzH)]⋅0.5Hexane (2 b), [La4O(Me2pz)10(Me2pzH)] (2 c) (from heating 1 a in toluene), [Ce3O(Me2pz)9K2(dme)2] (3 a), [Ce3O(Me2pz)9Li2(thf)2]⋅0.5Hexane (3 b) and [Ce(Me2pz)5Li2(thf)3] (3 c), which crystallized together, [Ce3O(Me2pz)10K3(thf)3] (3 d), [Pr3O(Me2pz)10K3(thf)3] (4), [Dy3O(Me2pz)9K2(thf)2]⋅THF (5), [Yb3O(Me2pz)9K2(thf)2]⋅THF (6), and [Lu3O(Me2pz)9K2(thf)2]⋅THF (7). Crystals of {[K8(Me2pz)8(thf)2]⋅THF}∞ (8) were also obtained from the preparation of 7. From reaction of [Ce(Me2pz)3(thf)]2 with potassium tert‐butoxide in toluene, the cerium(IV) heterobimetallic polymer [Ce2(Me2pz)6(OtBu)4K2]∞ (9) was isolated. In the Ln3O and the Ln4O cages, the Ln atoms have triangular and distorted tetrahedral arrangements about the central oxygen, respectively. The relationship of the alkali metals to the central oxygen varies considerably. Thus in 2 a, 2 b, there is no bonding, in 3 a, both K atoms interact weakly, in 3 b one of the two Li atom is bound, in 3 d, 4, one of three K atoms in bound, whilst in 5–7, both K atoms are bound. All metals are bound to the cages by a variety of pyrazolate binding modes, with up to five different exhibited in some structures, and a new coordination mode, μ4‐1κ(N):2κ(N′):η5:η5, was observed in two complexes. In the structure of 2 c, the coordinated Me2pzH ligand binds to two metals through a single nitrogen, the first time this has been observed for a pyrazole donor. The complex 9 is polymeric with all metals bridged by butoxide donors as well as by Me2pz groups. [ABSTRACT FROM AUTHOR]

The boron nitrides as excellent sensors are adopted to detect some harmful gases. The adsorption sites and lengths of the boron nitrides are very important to improve the adsorption capacity. The structures, stabilities and electronic properties of the COBmNm and CO@BmNm (m = 4 8 , 96 and 144) nanotubes with different lengths have been investigated by using density functional theory. The longer BmNm, COBmNm and CO@BmNm clusters are more stable. The adsorption of the CO molecules at the ends of BmNm nanotubes competes with the insertion of the CO molecules in the BmNm nanotubes. The COBmNm clusters exhibit higher chemical reactivity than the CO@BmNm clusters. The lengths of the BmNm nanotubes have little effect on the chemical reactivity of the nanotubes. The charge transfer amounts of the O atoms increase while those of the C atoms of the COBmNm and CO@BmNm clusters are almost the same with the increase of cluster lengths. The CO molecules lose fewer electrons (0. 1 7 4 | e | , 0. 1 6 4 | e | , 0. 1 5 8 | e |) to the BmNm nanotubes of the COBmNm clusters while the CO molecules obtain fewer electrons (− 0. 0 2 8 | e | , − 0. 0 4 5 | e | , − 0. 0 4 5 | e |) from the BmNm nanotubes of the CO@BmNm clusters. [ABSTRACT FROM AUTHOR]

The viscosity of CaO‐SiO2‐MgO‐Al2O3‐BaO‐MnO slag with a varying MnO content of 0–8 wt% is continuously measured, and the polymerized network changes are clarified by Fourier transform infrared reflection spectroscopy and X‐ray photoelectron spectroscopy. Thermodynamic calculation and X‐ray diffraction analysis are conducted to determine crystal phases variations. Finally, the relationship between viscosity and different structural parameters is discussed. The results indicate that an increase in MnO content decreases the viscosity from about ≈0.55 to 0.41 Pa·s at 1500 °C, and from 1.3 to 0.87 Pa·s at 1400 °C. The free running temperature also decreases. Ba2+ and Ca2+ are used for charge compensation of [AlO4], and Mn2+ mainly connects nonbridging oxygen to depolymerize the silicate network. The precipitation of crystal phases significantly increases the viscosity of the slag, and Mn2+ is mainly involved in the formation of silicate phases. Structure analyses suggest that an increase in MnO leads to a decrease in the amount of bridging oxygen, which reduces the degree of polymerization. In the composition range of blast furnace slag, the structural parameters change within a narrow range, and the viscosity has a negative correlation with NBO/T and optical basicity, yet a positive correlation with Q. [ABSTRACT FROM AUTHOR]

Endohedral metallo-borospherenes M@B40 have received considerable attention since the discovery of B40 in 2014. However, the coordination bonding nature of most of actinide-doped endohedral An@B40 still remains in dispute or unexplored. Extensive and systematic first-principles theory calculations performed herein unveil the ground states of triplet U@B40 (1, C2v, 3A2), quartet U@B40− (2, C2v, 4B1), quintet Np@B40+ (3, C2v, 5A1), sextet Np@B40 (4, C2, 6A), septet Pu@B40 (5, C2v, 7A2), octet Am@B40 (6, C2v, 8A2), and octet Cm@B40+ (7, C2v, 8A2) at the coupled-cluster with triple excitations CCSD(T) level. Detailed principal interacting spin orbital (PISO) and adaptive natural density partitioning (AdNDP) analyses reveal their coordination bonding patterns and show that, with the numbers of unpaired α-electrons in parallel spins varying from nα = 2, 3, 4, 5, 6, 7, to 7 in these complexes, the percentage contribution of the An 5f-involved PISO pairs to overall coordination bonding interactions decreases monotonously from 41% to 1%, and the contribution of An 6d-involved PISO pairs increases monotonously from 47% to 72%, while the marginal contribution of An 7s-involved PISO pairs remains basically unchanged (4~7%). The IR, Raman, and photoelectron spectra of the most concerned species are computationally simulated to facilitate their characterizations in future experiments. [ABSTRACT FROM AUTHOR]

Based on a combination of hexagonal honeycomb and re-entrant honeycomb cells, the concept of novel hybrid cell structures was developed. Experimental studies and numerical analyses of the behaviour of the analysed structures under in-plane compression in two compression directions were carried out. Explicit finite element analyses with an explicit integration scheme, incorporating plastic deformation and ductile damage evolution models, were employed to analyse the entire deformation process, including plastic and damage stages. Good agreement was obtained between the results of the numerical analyses and the experimental studies. [ABSTRACT FROM AUTHOR]

While social work education can provide students with rewarding and satisfying experiences, there can also be stressful and demanding requirements from academic and placement work and personal circumstances. Self-care encourages students to give more attention to their own needs in order to prepare themselves for potentially demanding careers in social work organizations, where they can continue self-care practices. Self-care activities can be taken for granted. They can be defined in diverse ways; they may involve physical, psychological, emotional, spiritual, personal, and professional elements. There are dangers that self-care activities can become excessively individualized, but they take place within structural, organizational, institutional, collective, and family contexts. The aims of this article are to explore definitions of self-care, to present recent international research findings about self-care in social work education and among social work students, to locate self-care in a wider organizational and societal context, to consider strengths, to critically evaluate some of the weaknesses of the concept, and to explore possible future development of self-care in social work education in the UK. [ABSTRACT FROM AUTHOR]

Cu2+‐ion‐doped cobalt ferrites with the chemical formula Co1–xCuxFe2O4 (0 < x ≤ 0.20) are prepared using the citrate–nitrate autocombustion method. The structural properties of the synthesized samples are examined by X‐ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and Raman spectroscopy. The XRD studies reveal the formation of a single‐phase spinel cubic structure. A slight variation in the peak position is observed with the addition of Cu2+ ions. The proposed cation distribution is supported by X‐ray relative intensity calculations. FTIR and Raman spectroscopy studies also confirm the formation of a single‐phase cubic structure. Field‐emission scanning electron microscopy (FESEM) is used to measure the surface properties of the samples. The FESEM images reveal nearly uniform‐sized grains with the addition of Cu2+ ions. The DC electrical resistivity is determined using the conventional two‐probe technique and is typically found within the range of 106 Ω cm−1. Dielectric measurements are performed using an impedance analyzer with 100 Hz–10 MHz frequency range and the variations in the dielectric properties are discussed. The magnetic properties are measured using a vibrating sample magnetometer conducted the magnetic measurements. The uneven variations in the magnetic properties are explained based on Neel's two‐sublattice model. [ABSTRACT FROM AUTHOR]

A self-oscillating system can harness energy from the external environment to sustain its continuous motion, making it highly suitable for applications in soft robotics, military industry, energy, and other fields. This article introduces a system composed of a light-responsive liquid crystal elastomer fiber, a baffle, and a spring, capable of achieving self-oscillation under stable lighting conditions. Considering the established dynamic model of light-responsive liquid crystal elastomers (LCEs), a nonlinear dynamic model is introduced and used as the basis for exploring its dynamic characteristics. Numerical computations reveal that the coupled system exhibits two distinct motion states: self-oscillation and static states. The behavior of the system is sustained through the interaction of light energy and damping dissipation. Furthermore, a detailed investigation is conducted on the key system parameters affecting the frequency and amplitude of self-oscillation. In contrast to the complexity of current self-oscillating systems, this particular self-oscillating system features simplicity in structure, ease of manufacture, and strong adaptability. These advantages are expected to provide broader design possibilities for micro-machines and mechanical production processes. [ABSTRACT FROM AUTHOR]

The paper presents the results of computer simulating the structure formation in nanodisperse magnetic fluids and the influence of this process on the kinetics of their magnetization reversal. The work considers a system of identical spherical single-domain ferromagnetic particles suspended in a Newtonian fluid with magnetic moments "frozen" into the particle bodies. The particles are involved in intense Brownian motion. The magnetic interactions of all particles with each other, as well as of the particles with an external magnetic field, are considered. The results have shown that the evolution of the internal structures upon a change in the external field can greatly, by several orders of magnitude, change the characteristic time of ferrofluid magnetization reversal. The results obtained may be useful for the development of both the general theory of these systems and many methods for their high-tech applications. [ABSTRACT FROM AUTHOR]

This article explores the urgent need for transformative change toward provisioning systems that align with staying as close as possible to the Paris Agreement's 1.5 °C limit for climate change. Despite historical awareness of the need for change, current unsustainable patterns of production and consumption persist, prompting an examination of the role of societal structures in hindering transformative change. Using the framework of provisioning systems, this study analyses expert and stakeholder views on structural barriers and steps to overcome them. Based on 36 expert interviews and Stakeholder Thinking Labs with 113 participants in five European Union case countries, the study identifies and discusses seven key structural barriers that affect the sustainability of provisioning systems for food, mobility, housing, and leisure. These barriers include the economic growth paradigm, policy incoherence, vested interests, the externalization of environmental costs, dominant narratives of the good life, inequality, and an insufficient integration of environmental concerns in educational systems. When considering the actualization of these structures in concrete provisioning systems, stakeholders emphasize the need for welfare provision with improved resource efficiency; argue for radical measures such as bans, limits, and taxes to address these challenges; and highlight governance challenges related to participation and power. The analysis underlines the complexity of promoting transformative structural change and the interplay of structures in different provisioning systems, emphasizing the need for a holistic approach to achieve sustainable provisioning systems and 1.5° lifestyles. [ABSTRACT FROM AUTHOR]

This research aimed to examine innovative concepts and introduce design advancements rooted in Tensegrity structures, commonly used in the fields of architecture and engineering. The inherent characteristics of structures, associated with the operational principles of compressive and tensile forces, lead to interconnected tensile elements, thereby forming a network. This network generates internal compressive forces in the transmission structures, without directly connecting the compressive or tensile components. Consequently, the potential of tensegrity structures lies in the robust, lightweight, flexible, adjustable, and adaptable nature, thereby making the structures suitable for diverse design applications. The main objective of this research is to investigate, hypothesize, and experiment to scrutinize and categorize design works across various domains, including architecture, interior design, and furniture design. The aim is to incorporate identified principles and properties to suit specific requirements. The specific objectives of this research are as follows: 1) investigate the historical evolution of tensegrity structures; 2) categorize structures based on their properties, facilitating their appropriate application in design; 3) develop products derived from the conceptual framework of tensegrity structures, with potential applications spanning various contexts, including furniture such as tables and chairs. A combination of computer simulations and physical models was also used to understand proportions and practical applications. The result showed that furniture design derived from the concept of tensegrity structures have the potential and capacity for further development into a variety of design expressions. This research provides an extensive background on tensegrity structures, covering definitions, classifications, properties, and applications. This research serves as a fundamental resource and a vital information repository for the proficient application, advancement, and design of comprehensive tensegrity structures. [ABSTRACT FROM AUTHOR]

Construction of infrastructures in cold regions and the Arctic has grown rapidly since the 2000s, including railways, platforms, bridges, roads, and pipelines. However, the harsh low temperatures significantly influence the mechanical behaviors of construction materials, and bring safety and durability challenges to these engineering structures. This study made a state‐of‐the‐art review on materials and structures exposed to low temperatures. This review started from constructional‐material mechanical properties, including concrete, steel reinforcement, mild/high‐strength steel plate, and steel strand at low temperatures. It reflected that low temperatures improved the strength of construction materials. However, the freeze–thaw cycles (FTCs) had a detrimental effect on the modulus and strength of concrete. Furthermore, it was revealed that low temperatures increased the interfacial bonding strength between the steel reinforcements (or shear connectors) and concrete. Moreover, low temperatures improved the bending, shear, and compression resistances of reinforced concrete (RC) or prestressed concrete structures, but reduced the ductility of RC columns under lateral cyclic loads. Finally, reviews also found that low temperatures improved the compression resistance of concrete‐filled steel tubes using mild, high‐strength, and stainless steels, whereas FTCs and erosion reduced their compression capacity. In addition, low temperatures increased the bending resistance of steel–concrete composite structures, but the FTCs reduced it. The low temperatures bring challenges to the safety and resilience of engineering constructions, which requires careful further studies. Continuous further studies may focus on the durability of materials and the resilience of structures under diverse hazards, including earthquakes, impacts, and even blasts. [ABSTRACT FROM AUTHOR]

This state-of-the-art innovatory overview essentially debates practical worth of three-dimensional printed composites/nanocomposites (especially carbon fiber designs) for aerospace sector. Recently, three-dimensional printing (additive manufacturing) has competently transpired for designing high performance space structures. The manuscript systematically frameworks fundamentals of three-dimensional printing approach, ensuing high-tech aeronautical carbon fiber composites/nanocomposite systems, and space components/structural applications. Amongst carbonaceous fillers, short/continuous carbon fibers were inspected as outperforming reinforcements for aerospace. Additionally, surface modified/composited carbon fibers with nanocarbons (carbon nanotube, graphene) have been reported. Accordingly, polyamide, poly(lactic acid), poly(ether ether ketone), epoxies, etc. have been documented as substantial thermoplastic/thermosetting matrices. Ensuing radical polymer/carbon fiber or polymer/carbon fiber/nanocarbon hybrids have benefits regarding low-cost manufacturing, structural precision, complex geometries, high efficiency, least structural defects/voids, superior tensile and shear strength/modulus, compression strength, interlaminar strength, wear properties, thermo-dimensional constancy, and heat stability features, under extreme space environments. Consequently, cutting-edge three-dimensional printed carbon fiber hybrids offered myriad of promising opportunities for mechanically robust (nozzle wearing, strengthened wing spar/ribs, resilient rotating components, interlaminar strength/dimensional stability) and high temperature stable (cryogenic fuel storage, lower earth orbital stability, thermal-dimensional steadiness, thermal conductivity) for aerospace modules. Henceforth, three-dimensional printing owns enormous engineering potential to meet aeronautical manufacturing demands by overcoming challenges of traditional techniques. [ABSTRACT FROM AUTHOR]

The objective of this study was to develop a type of glued laminated timber (Glulam) element from solid eucalyptus wood residues. The hybrid wood Eucalyptus urophylla × Eucalyptus grandis was used and characterized regarding its physical and mechanical properties to determine density, moisture content and dimensional stability. Glulam elements were manufactured from whole blades and residues, glued with resorcinol-formaldehyde adhesive and polyurethane. Non-destructive tests of free transverse vibration, longitudinal vibration and stress wave were conducted in Glulam elements, plus tests of compressive strength, parallel compressive strength, and shear strength in wood and glue joints under two moisture conditions (dry and saturated). Wood residues of the E. urophylla × E. grandis hybrid have good physical and mechanical properties that allow its use for the manufacture of Glulam elements. Adhesives showed high resistance when tested in dry condition but performed differently in saturated condition. The type of adhesive used did not differ in the resistance of Glulam. Glulam elements with residues showed satisfying results when compared to elements with whole blades, demonstrating that small pieces are useful for manufacture. [ABSTRACT FROM AUTHOR]

This study investigates the development and characterization of a novel composite material for structural applications, aiming to address the growing demand for lightweight, durable and versatile materials. The composite integrates aramid fibre reinforced with sawdust particulates within an epoxy matrix. Methodologically, the composite was fabricated using a hand layup process, ensuring even distribution and strong adhesion between components. Mechanical testing revealed significant enhancements in tensile strength (up to 135.29 MPa) and flexural strength (up to 136.92 MPa) with the inclusion of sawdust particulates, optimizing stress distribution and impact resistance. Hardness was also improved, peaking at a Rockwell hardness number of 94. Thermal analysis demonstrated moderate thermal conductivity (1.92 W mK−1) and a high heat deflection temperature (109 °C), indicating excellent thermal stability. SEM provided insights into the composite's microstructure, confirming uniform sawdust distribution and robust fibre–matrix adhesion. These findings underscore the potential of this composite for lightweight, durable and thermally stable structural applications. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

AbstractAuxetic materials and structures have been largely regarded because of their superior mechanical properties compared to other structures. These materials and structures contract (expand) laterally under uniaxial compression (tension). In this study, we have investigated different types of auxetic cells such as reentrant, chiral and non-chiral, rotating polygonal, and etc. Also, we have described their mechanical properties in a separate section. The applications of these cells were also investigated in various fields of automotive, medical and etc. In this study, in addition to previous works, recent works have also been introduced. Being a comprehensive reference for different types of auxetic cells, this study helps researchers design various auxetic structures. [ABSTRACT FROM AUTHOR]

In this study, LiGaCr4−xFexO8 (x = 0, 0.2, 0.4, 0.6) ceramics are synthesized using the solid‐phase reaction method. The effects of Fe doping on the lattice structure and dielectric properties are systematically examined using X‐ray diffraction (XRD), scanning electron microscopy (SEM), Raman spectroscopy, and dielectric measurements. It is found from XRD analysis that the evolution of lattice constant decreases from 8.2552 Å at x = 0 to 8.2449 Å at x = 0.6, demonstrating a lattice contraction with doping. SEM shows a grain size reduction and irregular structures with higher Fe doping levels developed. The grain size decreases from 1.716 μm at x = 0 to 1.155 μm at x = 0.6. Due to Fe doping, the Raman spectroscopy obviously changes in high‐frequency phonon modes. The F2g1 and A1g modes shift to higher frequencies due to the reduction in lattice constant, while the F2g2, F2g3, and Eg modes shift to lower frequencies due to the increased ionic mass caused by the heavier Fe ions. Notably, Fe doping increases the dielectric constant and reduces the dielectric loss, especially at higher doping level. In these results, it is suggested that moderate Fe doping improves dielectric properties, offering potential applications in microwave and high‐frequency devices. [ABSTRACT FROM AUTHOR]

During continuous casting process of high‐Mn high‐Al steel, soluble Al in the steel typically reacts with SiO2 in the mold flux, resulting in a decrease in SiO2 content and an increase in Al2O3 contents in the flux. The structure of slags with varying CaO/SiO2 and Al2O3/SiO2 mass ratio is investigated using Raman spectroscopy and nuclear magnetic resonance (NMR) spectroscopy. In the deconvolution results of Raman and NMR spectra, it is shown that the relative fractions of QSi0$Q_{\text{Si}}^{0}$ and QSi1$Q_{\text{Si}}^{1}$ significantly increase, while QSi2$Q_{\text{Si}}^{2}$ and QSi3$Q_{\text{Si}}^{3}$ gradually decrease with an increase in the CaO/SiO2 mass ratio from 0.52 to 1.02, resulting in depolymerization of the bridge oxygen structure. The silicon–oxygen tetrahedron transforms into aluminum–oxygen tetrahedron when the Al2O3/SiO2 mass ratio increased from 0.05 to 1.01. The viscosity of the slags with varying composition from 1573 to 1373 K is investigated. In the results, it is shown that with an increase in the CaO/SiO2 mass ratio, the viscosity decreases, and the complex SiO network structure is depolymerized. The viscosity decreases first as the Al2O3/SiO2 mass ratio increases from 0.05 to 0.24 and then increases as the mass ratio from 0.24 to 1.01, with the network formers transfer from SiO to SiAlO structures. [ABSTRACT FROM AUTHOR]

In order to understand the effect of different tube structures on the heat transfer characteristics of supercritical CO2 in heating serpentine micro‐tubes, five structures are investigated. At the same inlet Reynolds number, because the periodic disturbance frequency of boundary layer and centrifugal force decrease with the increase of curvature radius and the boundary layer thickens with the increase of tube diameter, the comprehensive heat transfer performance of serpentine micro‐tubes decreases with the increase of curvature radius and tube diameter. Gravitational buoyancy is independent of curvature radius but increases with the increase of tube diameter. Centrifugal force and centrifugal buoyancy decrease with the increase of curvature radius and tube diameter. [ABSTRACT FROM AUTHOR]

Pea (Pisum sativum) protein, as a pulse protein second only to soy protein, has shown increasing popularity in the plant-based food market. Numerous studies have shown the desirable techno-functionalities of pea protein for emulsifying, gelling, and foaming. Nevertheless, poor digestibility and unpleasant beany flavors of pea protein lower consumer acceptance. The current state of understanding on digestibility and beany attributes of pea proteins could help pave the way for pea protein-based food formulation with improved quality. This paper covers recently reported studies to modulate the digestibility and beany notes of pea protein by many processing techniques, and highlights the influence of non-protein components and food matrix structures while formulating pea protein-based food systems. Several modification techniques could alter the digestibility and improve the flavor of pea proteins by reorienting the protein structures or forming protein-based complexes. Precise tailoring the digestibility/flavor of pea proteins is promising based on current research, though further investigation is still required to reduce adverse effects or side products. In addition, more studies on simulated pea protein-based food systems are required to mimic the actual food comprising multi-components and specific structures to narrow the gap between lab-scale research and food industry applications. [ABSTRACT FROM AUTHOR]

Utilizing the flexible carboxylic acid ligand, tri (4‐carboxybenzyl) amine (H3L), three new metal organic frameworks Na[Cd(L)]n ⋅ 3nH2O (1), [Cd(HL)(4,4'‐bipy)0.5(H2O)]n (2) (4,4'‐bipy=4,4'‐bipyridine) and [Cd(HL)(2,2'‐bipy)]n (3) (2,2'‐bipy=2,2'‐bipyridine) have been successfully synthesized. Compounds 1 and 2 are 2D structures with (3,6) 2‐nodal as kgd topology, while compound 3 is a 1D chain structure. The powder X‐ray diffraction and thermal stability of 1–3 were studied. In addition, the solid‐state luminescence properties of compounds 1–3 at room temperature were also tested, indicating their application prospects in fluorescent materials. [ABSTRACT FROM AUTHOR]

Background: Thyroid dysfunction and frontal lobe gray matter volume (GMV) alterations are associated with violence in schizophrenia (SCZ); however, little is known about the relationship between thyroid dysfunction and frontal lobe GMV. This study aimed to evaluate whether thyroid hormone levels were associated with frontal lobe GMV in male patients with schizophrenia and violence. Methods: Fifty-five male patients with SCZ underwent triiodothyronine (T3), thyroxine (T4), thyroid-stimulating hormone (TSH), free triiodothyronine (fT3), and free thyroxine (fT4) tests and structural magnetic resonance imaging (sMRI) scans. The sMRI data were processed using the FreeSurfer version 5.0. Multiple linear stepwise regression analysis was used to investigate the relationship between frontal lobe GMV and thyroid hormone levels in all patients. Results: Patients with SCZ and violence exhibited lower GMV of the left frontal pole and higher TSH levels than those without violence. After controlling for potential covariates, the frontal pole GMV was negatively associated with TSH levels in all participants. Conclusion: These findings expand our understanding of the influence of TSH on frontal pole GMV in patients with schizophrenia and violence. [ABSTRACT FROM AUTHOR]

The 28 cooling towers of the French Nuclear Power Plants (NPP) fleet have been studied using a digital twin automated approach that allows a better understanding of their behaviour and includes on-site measurements such as settlement displacements and predicted corrosion as inputs in a linear Finite Element Model (FEM). Advanced simulations are then built upon this digital twin, providing a more precise simulation of the ultimate mechanical behaviour of the tower, with a non-linear FEM allowing steel and concrete damage. Finally, increasing wind load is applied until the structure reaches a near-collapse state, allowing us to conclude on the mechanical margin and the need for reinforcement. [ABSTRACT FROM AUTHOR]

Materials and structures with tunable mechanical properties are essential for numerous applications. However, constructing such structures poses a great challenge since it is normally very complicated to change the properties of a material after its fabrication, particularly in pure force fields. Herein, we propose a multistep and elastically stable 3D mechanical metamaterial having simultaneously tunable effective Young's modulus and auxeticity controlled by the applied compressive strain. Metamaterial samples are fabricated by 3D printing at the centimetric scale, with selective laser sintering, and at the micrometric scale, with two-photon lithography. Experimental results indicate an elementary auxeticity for small compressive strains but superior auxeticity for large strains. Significantly, the effective Young's modulus follows a parallel trend, becoming larger with increasing compressive strain. A theoretical model explains the variations of the elastic constants of the proposed metamaterials as a function of geometry parameters and provides a basic explanation for the appearance of the multistep behavior. Furthermore, simulation results demonstrate that the proposed metamaterial has the potential for designing metamaterials exhibiting tunable phononic band gaps. The design of reusable elastically stable multistep metamaterials, with tunable mechanical performances supporting large compression, is made possible thanks to their delocalized deformation mode. [ABSTRACT FROM AUTHOR]

With the size reduction of structures into micro/nanoscale, the size-dependent effect arises in mechanical properties. For micro/nanostructures working in transient thermal environment, the thermal relaxation needs to be considered in heat conduction. Functionally graded carbon nanotubes/graphene platelets reinforced composite (FG-CNTRC/GPLRC) materials as new generation of advanced materials have attracted much attention due to their excellent mechanical or thermoelastic performance. Though the mechanical or non-coupled thermoelastic behaviors of beam, plate and shell made of FG-CNTRC/GPLRC materials have been extensively studied, there lacks of investigations on the coupled thermoelastic behaviors of micro/nanostructures of FG-CNTRC/GPLRC in the context of generalized thermoelasticity where both the elastic nonlocality and thermal relaxation need to be considered. To fill this gap, in this work, the Lord–Shulman (L-S) type generalized thermoelasticity incorporating the fractional-order nonlocal theory is applied to investigating the thermoelastic bending wave propagation characteristics of a nanocomposite microbeam reinforced by GPLs and CNTs simultaneously for the first time. The Halpin–Tsai micromechanical model is used to assess the effective elastic modulus and the other properties are evaluated by the rule of mixture. Then, the governing equations are formulated based on the Euler–Bernoulli beam model. By assuming the wave-type solutions, the governing equations are solved and the dispersion relation between frequency and wave number and the relation between phase velocity and wave number are determined, respectively. In calculation, the effects of the thermal relaxation time, the elastic nonlocal parameter, the fractional order parameter and the mass fractions of GPLs and CNTs on the dimensionless frequency and phase velocity are analyzed and discussed in detail. [ABSTRACT FROM AUTHOR]

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Purpose. To develop a method for predicting fractured zones in a massif of sedimentary rocks formed due to the folding, by determining relative linear deformations that exceed those critical ones for discontinuity of rock massif. Methodology. The task of identifying fractured zones is to determine areas in the rock massif where tensile deformations, under the action of tectonic processes, have exceeded the critical limit. The determination requires the map construction of the researched area with the help of trend analysis and a series of mathematical calculations, namely, finding the distance between the selected points of the direction and along the arc connecting them within the interpolating surface. The length of the last curve is found by integration. The coefficient of relative linear deformation is the result of dividing the found distances (the length of the arc by the length of the line). Findings. A new methodology for predicting fractured zones in a massif of sedimentary rocks formed due to the folding is proposed. The methodology was developed based on an algorithm that involves calculating the relative linear deformations of the bed by constructing maps of local structures of the researched area and a series of mathematical calculations. Using the example of the “Chaikino” minefield, the authors present the concrete result of determining the relative linear deformations of the rock massif. An anticlinal local structure (the 2ndorder structure) was identified within the minefield, the parameters of the structure were determined, and calculations were performed according to the appropriate algorithm. The obtained data indicate that the real values of relative linear deformations (1.011 and 1.034) significantly exceed the critical limit for sandstones (1.003–1.004). This indicates the discontinuity of rock massif and the presence of the fractured zone. Originality. For the first time, the methodology has been developed that allows determining the relative linear deformations of rocks between any individual points within the researched area, based on the coordinates of the points’ location in the plan and the hypsometric marking of the bed. Practical value. The proposed methodology can be used to solve several geological problems directly related to the research and detection of fracturing, which was formed under the action of tectonic forces in the process of folding. [ABSTRACT FROM AUTHOR]

This study explores the effectiveness of using comic strips as a psycholinguistic approach to enhance Arabic speaking proficiency (maharat al-kalam) among students. Traditional methods of teaching Arabic often emphasize grammar memorization, which can disengage students and hinder their ability to apply the language in spoken contexts. In contrast, comic strips provide a visual and narrative framework that makes learning more engaging, promoting better vocabulary retention and comprehension of sentence structures. Quantitative data was gathered through pre-tests, post-tests, and speaking tasks, while qualitative data was obtained from questionnaires and semi-structured interviews. The results showed significant improvement in the experimental group in terms of vocabulary retention, sentence structure comprehension, and speaking confidence. The visual and contextual elements of comic strips helped students internalize the language more effectively. Additionally. However, some challenges were noted in understanding cultural contexts within the comic strips. Notably, while comics are typically used to motivate and enhance maharat al-qiro'ah (reading skills), this study found that they can also be effectively applied to improve maharat al-kalam (speaking skills) through the incorporation of Arabic vocabulary and a psycholinguistic approach. This study concludes that comic strips offer a valuable and innovative tool for enhancing Arabic speaking proficiency, providing both cognitive and motivational benefits.

To determine the effect of the embedded Cu, Ag, and Au on the electronic properties of tungsten oxides, the structures, stability, and electronic properties of the TMn@W12O36 (TM = Cu, Ag and Au, n = 1–4) clusters have been investigated by using density functional theory. The results reveal that the embedded TMn clusters decrease the structural stability of the W12O36 cages. The Ag@W12O36 and Ag3@W12O36 clusters exhibit higher structural stability than other TM@W12O36 and TM3@W12O36 (TM = Cu and Au) clusters. The Cu3 clusters prefer to be embedded into the W12O36 clusters. The embedded TMn clusters increase obviously the chemical reactivity of the W12O36 cages. The chemical reactivity of the Ag2@W12O36 and Ag4@W12O36 clusters is similar to that of the Cu2@W12O36 and Cu4@W12O36 clusters. The Au@W12O36, Au2@W12O36, Ag3@W12O36 and Au4@W12O36 clusters display more chemical stability. The charge transfer amounts between the Ag and O atoms of the TMn@W12O36 clusters are larger than those between the Cu (Au) and O atoms of them. [ABSTRACT FROM AUTHOR]

To delve into the microscopic property of the cluster RhSin (n = 6–15), this study employs the CALYPSO structure prediction program and density functional theory. The paper conducts a comprehensive theoretical analysis of the clusters, examining parameters such as structures, relative stabilities, charge transfer, vertical electron affinity, vertical ionization potential, chemical potential, chemical hardness, and infrared and Raman spectra. The optimization process reveals that the rhodium doping has clearly changed the structures of silicon clusters. The ground state geometries favor Rh-linked framework beginning from n = 6, and they favor Rh-encapsulated Si cages when n approach 10. RhSi13 cluster is more stable than its neighbors. The charges transfer within the clusters always transfer from silicon atom to rhodium atom, and there is spd hybridization in RhSin cluster. The analyzed chemical potential and chemical hardness pointed out the RhSi13 cluster has the stronger hardness than other clusters. At last, the infrared and Raman spectrum properties for RhSi13 cluster are analyzed. [ABSTRACT FROM AUTHOR]

Abstract Lately, Saudi Arabia has been developing its mineral exploration. However, comprehensive studies of the collected data are not accessible. Thus, the purpose of this research is to identify and map the hydrothermal alteration zones and structural lineaments that regulate the mineral occurrences in the Nuqrah region of the Kingdom of Saudi Arabia using remote sensing and aeromagnetic data. To achieve the desired goal of the study, ASTER remote sensing data were employed, and they were processed in several ways, including principal component analysis, band ratio, and false color composites to reveal the zones of alteration and structure lineaments. In addition, aeromagnetic data was employed to map the lineaments controlling the mineralization. These datasets were integrated using GIS tools to generate a new mineralization potential map of the Nuqrah area, which was classified into three classes: low, moderate, and high probability mineralization. The results showed thirteen intriguing anomalies (high potential mineralization) dispersed over the research area to be prospected. Additionally, techniques such as residual, regional, first vertical derivative, and tilt derivative were utilized to detect the potential mineral-related geologic structures. The results were validated by plotting known mineralization sites on our maps. Six significant faulting trends have been found, according to the lineament map and rose diagrams from remote sensing: NE–SW, WNW–ESE, N–S, ENE–WSW, NNE–SSW, NW–SE, and E–W. The research region is most affected by the NW–SE, ENE–WSW, E–W, and N–S trends, which are organized in decreasing order of magnitude, according to the rose diagram of the aeromagnetic maps. The applied approach can be employed to map potential mineral deposits in Saudi Arabia and similar zones around the globe.

Introduction. Domestic and foreign experience of full-scale tests is analyzed. The retrospective of development of standards for conducting full-scale tests in Russia and the USSR is presented. The review of the world regulatory documents regarding the requirements for conducting full-scale tests of structures is carried out, which showed insufficient research of this question both in our country and abroad. The obtained review can be the basis for the development of the national standard of the Russian Federation for conducting full-scale tests.Materials and methods. Analytical review.Results. The state of the issue and the application of stress tests (full-scale tests) in our country, as well as in Germany, the USA, Italy, Canada, Australia, Switzerland and other countries are shown. The minimum requirements for the target test load during testing, the loading mode and acceptance criteria for the experimental assessment of the load-bearing capacity of existing load-bearing structures specified in various standards are given. Specialized criteria for the acceptance of load-bearing structures, such as the permanency ratio and deviation from linearity index, mentioned in individual standards, are analyzed.Conclusions. The similarity of common approaches and the lack of unified requirements for conducting this type of research and evaluating their results are noted. The necessity to develop a national standard of the Russian Federation for full-scale tests of erected reinforced concrete structures is considered.

The family is the fundamental pillar of the society and is subject to psychological rules and legal regulations, and with the good implementation of these rules and regulations, it can achieve the excellence of the family members and the consolidation and improvement of its structure. In the event of couple's divorce and the occurrence of the conflict between the duty of mother's custody and the limits of the patriarch's guardianship, by strengthening the extended family structure and paying attention to the participation of different classes of the family, it is possible to benefit from the conditions that have arisen for the benefit of the relationship between generations, and to establish the legal criteria for legislation. Coercive rule was achieved. The current research aims to investigate the psychological impact of the type of family structure and the different states of participation of the members in each of the structures to overcome the legal conflicts that have arisen between the performance of the custodian and the coercive guardian. The results of the investigations show that in the conditions of generation gap and the existence of a significant distance between the family of the first degree and the family of the second and third degrees, the fields of mutual understanding and effective participation have been lost and not only the interaction of the guardian and the forced guardian get into trouble after divorce, but perhaps this emptiness would be one of the causes of divorce. As a result, it is necessary to provide the conditions for the participation of different family classes in different intellectual, cultural, and economic contexts, even when there is no context for changing the family structure, and the threat of alienation of relatives becomes an opportunity for their cooperation and assistance.