Search Results (64)

This study introduces and validates a miniaturized testing methodology for the complete orthotropic characterization of structural plywood, including out-of-plane directions that are typically difficult to access. Novel small-scale geometries were developed for tension and shear configurations, with compliance corrections applied to ensure accurate stress–strain responses. The method proved reliable and sensitive to mechanical differences arising from veneer architecture, adhesive type, and interfacial bonding. Two sets of 18 mm structural plywood panels—manufactured with distinct adhesive systems, one bio-based (F1) and one phenol-formaldehyde (F2)—were systematically tested under tensile, compressive, and shear loading in ten orthogonal configurations (T_x, T_y, T_z, C_x, C_y, C_z, τ_xy, τ_yx, τ_xz, τ_yz), following standards NCh 3617, EN 789, and ASTM B831. Tensile moduli were approximately twice the corresponding compressive values, while out-of-plane moduli reached only 6–11% of in-plane values. F1 exhibited higher stiffness in both tension and compression, particularly in transverse directions, due to thicker perpendicular veneers enhancing bending restraint and shear coupling. In contrast, F2 achieved greater peak shear strength owing to its more uniform veneer structure, which improved stress distribution and delayed interlaminar failure. Observed asymmetry between tension and compression reflected microstructural mechanisms such as fiber alignment and cell-wall buckling. The miniature-specimen data provide reliable input for constitutive calibration and finite-element modeling, while revealing clear links between veneer-thickness distribution, shear-transfer efficiency, and macroscopic performance. The proposed framework enables efficient, reproducible orthotropic characterization for optimized, lightweight, and carbon-efficient timber systems. Full article

The consequent-pole interior permanent-magnet (CPM) motor is a promising alternative for minimizing rare-earth magnet usage while supporting high-speed operation. However, rotor flux asymmetry often leads to distorted back-electromotive force waveforms and increased torque ripple. This study investigated a flared-type CPM motor that employs ferrite magnets arranged in a flared configuration to enhance flux concentration within a compact rotor. To address waveform distortion, structural modifications such as bridge removal and an asymmetric air-gap design were implemented. Three rotor parameters—polar angle, asymmetric air-gap length, and rotor opening length—were optimized using Latin hypercube sampling combined with an evolutionary algorithm. Finite element method analyses conducted under no-load and rated-load conditions showed that the optimized model achieved a 77.8% reduction in torque ripple, a 43.4% decrease in cogging torque, and a 0.5% improvement in efficiency compared with the basic model. Stress analyses were performed to examine the structural bonding strength and rotor deformation of the optimized model under high-speed operation. The results revealed a 5.5× safety margin at four times the rated speed. The proposed approach offers a cost-effective and sustainable alternative to rare-earth magnet machines for high-efficiency household appliances, where vibration reduction, cost stability, and energy efficiency are critical. Full article

Based on data from Chinese corporate bonds issued between 2014 and 2023, this study examines how ESG rating disagreement affects credit spreads. The results indicate that such disagreement significantly increases spreads through financial risk and information asymmetry channels, though this effect is mitigated by higher bond ratings. The impact is more pronounced in developed regions, highly marketized areas, less polluted and less competitive industries, non-Big Four audited firms, small enterprises, and state-owned enterprises. Increases in credit spreads are mainly driven by environmental and social rating disagreements, with the governance dimension playing a limited role. Full article

Understanding and controlling thermal rectification is pivotal for designing phononic devices that guide heat flow in a preferential direction. This study investigates one-dimensional atomic chains with binary mass asymmetry and nonlinear interatomic potentials, focusing on how energy propagates under thermal and wave excitation. Two potential models—the β-FPU and Morse potentials—were employed to examine the role of nonlinearity and bond softness in energy transport. Simulations reveal strong directional energy transport governed by the interplay of mass distribution, nonlinearity, and excitation type. In FPU chains, pronounced rectification occurs: under “cold-heavy” conditions, energy in the left segment increases from ~1% to over 63%, while reverse (“hot-heavy”) cases show less than 4% net transfer. For wave-driven excitation, the rectification coefficient reaches ~0.58 at 100:1. In contrast, Morse-based systems exhibit weaker rectification (∆E < 1%) and structural instabilities at high asymmetry due to bond breaking. A comprehensive summary and heatmap visualization highlight how system parameters govern rectification efficiency. These findings provide mechanistic insights into nonreciprocal energy transport in nonlinear lattices and offer design principles for nanoscale thermal management strategies based on controlled asymmetry and potential engineering. Full article

This study leverages emotional arc modeling along with close reading to examine the Chinese Ye Xian, Perrault’s Cendrillon, and two Grimm versions. While computational modeling suggests that Cinderella tales share similar “recognition scaffolds,” their emotional architectures reflect distinct moral universes. Story peaks and valleys vary according to individual narrative resolutions to a universal problem of virtue unrecognized. Ye Xian descends to maximum negative sentiment when sacred bonds rupture, aligning with Buddhist-Daoist ethics in which divine-human reciprocity supersedes other bonds. Perrault’s arc offers surprising asymmetry: linguistic violence (Culcendron) defines every valley, while material transformation marks every peak. The 1812 Grimm tale oscillates between degradation and elevation with peaks and valleys suggestive of a syncretism between folk magic and Protestant theology. The 1857 version flattens into a rough semblance of Perrault’s emotional architecture, but peaks and valleys reflect Protestant, rather than aristocratic, values. These many shapes of Cinderella suggest fairy tales may serve as a flexible emotional technology. Themes of good and evil are key features of these emotional architectures, but how they are expressed vary from tale to tale. Full article

Aquaglyceroporins, including human AQP7, AQP10, and E. coli GlpF, are known to facilitate movements of glycerol, water, and some other uncharged molecules across the cell membrane. In this study we focused on the transport of water molecules in the absence of glycerol for AQP7, AQP10 and GlpF using the Transition State Theory for the novel application of permeability and kinetics studies. We conducted around 500 ns of in silico simulations of the aquaglyceroporins embedded in lipid bilayer membranes with intracellular-extracellular asymmetries in leaflet lipid compositions. For the water permeability analysis, we computed the transition rate constant with correction for recrossing events where the water molecules do not completely traverse the protein channel from one side of the membrane to the other side. We also studied the hydrogen bond distributions of the single-file waters and channel residues and linear water densities along the pores of the aquaglyceroporins. Interestingly, we found that there was an inverse correlation between the number of single-file water molecules in the channel and osmotic permeability. Full article

Friction Stir Welding (FSW) is widely used for high-strength aluminum alloys due to its solid-state bonding, which ensures superior weld quality and service stability. However, thermo-mechanical interactions during welding can induce complex residual stress distributions, compromising joint integrity. Previous studies have primarily focused on thermal load-driven stress evolution, often neglecting mechanical factors such as the shear force generated by the stirring pin. This study develops a three-dimensional thermo-mechanical coupled finite element model based on a moving heat source. The model incorporates axial pressure from the tool shoulder and torque-derived shear force from the stirring pin. A hybrid surface–volumetric heat source is applied to represent frictional heating, and realistic mechanical boundary conditions are introduced to reflect actual welding conditions. Simulations on AA6061-T6 aluminum alloy show that under stable welding, the peak temperature in the weld zone reaches approximately 453 °C. Residual stress analysis indicates a longitudinal tensile peak of ~170 MPa under thermal loading alone, which reduces to ~150 MPa when mechanical loads are included, forming a characteristic M-shaped distribution. Further comparison with a Coupled Eulerian–Lagrangian (CEL) model reveals stress asymmetry, with higher tensile stress on the advancing side. This is primarily attributed to the directional shear force, which promotes greater plastic deformation on the advancing side than on the retreating side. The consistency between the proposed model and CEL results confirms its validity. This study provides a reliable framework for residual stress prediction in FSW and supports process parameter optimization. Full article

Structural microheterogeneity arising from the cooperative nature of hydrogen bonding is a critical yet often overlooked factor in the mechanistic understanding of physicochemical and biological processes occurring in aqueous environments. MD simulations using a potential that accounts for molecular flexibility and directional interactions revealed inhomogeneity arising from patches of continuously connected, four-bonded molecules embedded within a less ordered, space-filling hydrogen-bond network. The size of these patches follows a statistical distribution that is strongly temperature-dependent. With increasing temperature, the average size of the patches decreases, whereas the contribution of molecules forming the inter-patch zones becomes more pronounced. The nature of microheterogeneity is evidenced by temperature-dependent changes in the asymmetry of calculated power spectra as well as in the measured IR absorption within the stretching, bending, and combination band regions. A novel method for band analysis incorporates the calculation of skewness and a mirroring procedure for more accurate determination of FWHM of asymmetric bands. Discontinuities in the temperature dependence of spectral parameters observed within the 5–80 °C range correspond to the thermodynamic anomalies of liquid water. We show that structural microheterogeneity persists near 100 °C, suggesting that aqueous processes are better described by statistical distributions than by uniform models. Molecular simulations and IR spectroscopy offer key insights into these distributions. Full article

This study comparatively examines the determinants of yield spreads for Sukuk and conventional bonds, with a particular focus on the role of firms’ environmental, social, and governance (ESG) performance. Using a dataset comprising 744 bond-year observations from issuers in countries with prominent dual financial systems—namely, Saudi Arabia, UAE, Turkey, Malaysia, and Indonesia—over the period 2008 to 2022, this analysis identifies distinct mechanisms that influence yield spreads in these asset classes. For robustness, the sample excludes financial institutions to prevent industry-weight distortion and to account for their distinct risk–return profiles, which require differentiated valuation approaches for conventional bonds and Sukuk. Drawing primarily on decoupling, information asymmetry, and legitimacy theories, our empirical results reveal that robust ESG performance is significantly associated with lower yield spreads for both Sukuk and conventional bonds. Moreover, the study explores the moderating effect of investment horizons on the ESG–yield spreads relationship, uncovering evidence of differentiated investor behavior in relation to yield curve positioning. These findings, robust across various regression specifications, underscores the pivotal role of ESG factors as firm-level drivers of financing costs, offering new insights for scholars, policymakers, and practitioners in the sustainable finance domain. Full article

Financial stability analysis requires volatility modeling, especially in emerging nations where pension fund systems are very vulnerable to macrofinancial risks. In order to examine the volatility dynamics of Romania’s private pension system, this study uses daily net asset value (NAV) data from 2012 to 2024 to evaluate four GARCH-type models: standard GARCH (sGARCH), exponential GARCH (EGARCH), Glosten–Jagannathan–Runkle GARCH (GJR-GARCH), and component GARCH (C-GARCH). The analysis includes domestic and international equity indices (BET, STOXX), government bond yields (ROMGB 10Y, ROMANI 5Y), short-term interbank rates (ROBOR ON), and exchange rate fluctuations (RON/EUR). Current findings indicate that EGARCH captures asymmetric fluctuations in pension fund performance, where positive shocks generate larger increases in volatility than negative ones, highlighting an atypical asymmetry pattern. Furthermore, the stabilizing effects of government bonds are overshadowed by stock market behavior, which becomes the primary driver of risk. Fluctuations in exchange rates further increase volatility, especially in markets vulnerable to external disturbances. The findings offer empirical evidence for the necessity of more cautious risk management approaches and highlight the importance of regulatory oversight in maintaining market confidence. The study underscores the importance of customized allocation frameworks that reduce vulnerability to disruptive events while maintaining prospects for sustained growth. This new dataset contributes to enhancing the comprehension of pension fund volatility within the context of emerging markets. These insights can assist managers and policymakers seeking to fortify retirement outcomes. Full article

Nonverbal connection is an important aspect of everyday communication. For romantic partners, nonverbal connection is essential for establishing and maintaining feelings of closeness. EEG hyperscanning offers a unique opportunity to examine the link between nonverbal connection and neural synchrony among romantic partners. This current study used an EEG hyperscanning paradigm to collect frontal alpha asymmetry (FAA) signatures from 30 participants (15 romantic dyads) engaged in five different types of nonverbal connection that varied based on physical touch and visual contact. The results suggest that there was a lack of FAA while romantic partners were embracing and positive FAA (i.e., indicating approach) while they were holding hands, looking at each other, or doing both. Additionally, partners’ FAA synchrony was greatest at a four second lag while they were holding hands and looking at each other. Finally, there was a significant association between partners’ weekly negative feelings and FAA such that as they felt more negative their FAA became more positive. Taken together, this study further supports the idea that fleeting moments of interpersonal touch and gaze are important for the biological mechanisms that may underlie affiliative pair bonding in romantic relationships. Full article

In this study, we investigate the volatility spillover effects across uncertainty indices (Infectious Disease Equity Market Volatility Tracker (IDEMV) and Geopolitical Risk Index (GPR)), carbon emissions, crude oil, natural gas, and green assets (green bonds and green stock) under extreme market conditions based on the quantile connectedness approach. The empirical findings reveal that the total and directional connectedness across green assets and other variables in extreme market conditions is much higher than that in the median, and there is obvious asymmetry in the connectedness measured at the extreme lower and upper quantiles. Our findings suggest that the uncertainty caused by COVID-19 has a more significant impact on green assets than the uncertainty related to the Russia–Ukraine war under normal and extreme market conditions. Furthermore, we discover that the uncertainty indices are more important in predicting green asset volatility under extreme market conditions than they are in the normal market. Finally, we observe that the dynamic total spillover effects in the extreme quantiles are significantly higher than those in the median. Full article

This paper presents the efficient reduction of phosphinoylacetic acid esters and 3-phosphorylated coumarin to their corresponding phosphino-boranes using BH₃-THF complexes. Optimized conditions for the reduction of phosphinoylacetic acid esters resulted in high yields of phosphinoborates. The straightforwardness and efficiency of the process were demonstrated for diarylphosphinoylacetic acid ethyl esters, as well as P-stereogenic L-menthyl esters, where the simultaneous reduction of the strong P=O bond and the ester group was exclusively observed for the first time. The study also highlighted the significant influence of steric effects with bulky substituents, such as the menthol group or the 1-naphthyl substituent at phosphorus, on the reduction efficiency. However, the reduction of 3-phosphorylated coumarins produced an unexpected reaction product: a 2,3-dihydrobenzofuran derivative. The present findings provide valuable information on the direct reduction of phosphine oxides and related compounds, demonstrating the versatility of borane complexes in synthetic chemistry, and provide new perspectives for studying the problems of symmetry and asymmetry in the chemistry of such transformations. Full article

This paper’s objective is to examine the asymmetric cointegration and asymmetric effects of financial development and monetary policy on monetary transmission mechanisms in the Nigerian context using annual data spanning the period from 1986 to 2023. This study pushes the frontiers of knowledge by providing information on the nonlinear impacts of monetary policy and financial sector innovations on monetary transmission mechanisms in Nigeria to help policymakers tailor their strategies to local conditions, enhancing the effectiveness of monetary interventions in the economy. To achieve this, this paper adopted nonlinear ARDL models to understand how changes in the direction of monetary policy and developments in the financial system induce changes in the transmission of monetary policy. The findings document the existence of asymmetries in both the short and long run, revealing that the impacts of financial development and monetary policy on the different monetary policy channels are not uniform. These asymmetries indicate that the responses of various economic variables to monetary policy actions differ depending on the level of financial development. These findings underscore the complexity of the monetary transmission mechanism and the necessity for a nuanced understanding of how financial development and monetary policy interact in different contexts. Consequently, this finding is symptomatic of some characteristics of those financial markets on their way toward advanced developments. As the financial system matures, monetary policy may have a greater impact on the cost of short-term funding for banks without having any discernible effect on the rates at which businesses and households access funding. Therefore, this paper recommends focusing on the policies that will foster the financial system across the banking sector, capital market, bond market, and overall financial sector to improve the efficiency of the monetary transmission process. Full article

In the case of certain chemical compounds, especially organic ones, electrons can be delocalized between different atoms within the molecule. These resulting bonds, known as resonance bonds, pose a challenge not only in theoretical descriptions of the studied system but also present difficulties in simulating such systems using molecular dynamics methods. In computer simulations of such systems, it is often common practice to use fractional bonds as an averaged value across equivalent structures, known as a resonance hybrid. This paper presents the results of the analysis of five forms of C₆₀ fullerene polymorphs: one with all bonds being resonance, three with all bonds being integer (singles and doubles in different configurations), one with the majority of bonds being integer (singles and doubles), and ten bonds (within two opposite pentagons) valued at one and a half. The analysis involved the Shannon entropy value for bond length distributions and the eigenfrequency of intrinsic vibrations (first vibrational mode), reflecting the stiffness of the entire structure. The maps of the electrostatic potential distribution around the investigated structures are presented and the dipole moment was estimated. Introducing asymmetry in bond redistribution by incorporating mixed bonds (integer and partial), in contrast to variants with equivalent bonds, resulted in a significant change in the examined observables. Full article