In this paper, we study the nonlinear wave propagation of the fractional Joseph-Egri equation by means of the modified Sardar sub-equation method. The non-linear model under consideration includes Riemann-Liouville fractional derivatives, which are efficient in reflecting memory and heredity phenomena that are often present in complex physical media, such as polymers, gels, and biological tissues. With the aid of a proper traveling wave transformation, we reduce the non-linear partial differential equation to an ordinary differential equation. Finally, we use the modified Sardar sub-equation method to obtain various non-linear solutions, including bright soliton, dark soliton, dark singular soliton, periodic singular, and rational waves. By means of graphical analysis, we examine the effect of the fractional parameters alpha and beta on the non-linear solutions. In order to further validate the accuracy of the analytical results, numerical approximations of the solution have been carried out by employing the differential transform method, which has revealed an excellent agreement between the exact and numerical results with very small absolute errors. Moreover, an analysis of modulation instability is carried out in order to validate the stability of the background wave. The results have shown that the perturbation frequency is real for the considered parameter condition, thus validating that the system is modulationally stable. The results have revealed that fractional derivatives play an important role in governing wave attenuation, dispersion, and localization in viscoelastic media, thus providing more insight into nonlinear wave propagation in complex systems. The novelty of the study lies in the application of the modified Sardar sub-equation method, which provides a systematic and efficient framework for generating a wide variety of exact nonlinear wave solutions. Unlike many conventional analytical techniques that yield limited solution structures, the proposed approach enables the construction of bright, dark, singular, periodic, and rational wave solutions within a unified formulation.
This study reports the synthesis and characterization of a new tetradentate dioxime ligand (H2L) and its cobalt(III) complexes, [CoHLCl2], [CoHLBr2], and [CoLpyBr]Br. The complexes were fully characterized by elemental analysis, mass spectrometry, FTIR, UV-Vis, NMR, PXRD with Rietveld refinement, cyclic voltammetery, SEM, and zeta potential measurements, complemented by DFT calculations. The axial ligand significantly influences the structural, electronic, and catalytic properties. All complexes adopt a distorted octahedral geometry (triclinic, P-1 space group) with the dioxime ligand occupying equatorial positions. The HOMO-LUMO gap increases as [CoHLpyBr]Br (5.424 eV) < [CoHLBr2] (5.619 eV) < [CoHLCl2] (6.032 eV), correlating with chemical hardness and electrophilicity. The complexes exhibit efficient oxidase-mimetic catalytic activity for the aerobic oxidation of catechol derivatives (3,5-DTBCH2, 4-TBCH2, pyrocatechol, and 4-nitrocatechol) to the corresponding quinones. Catalytic activity follows the order [CoHLpyBr]Br > [CoHLCl2] > [CoHLBr2], with turnover frequencies reaching 21.84 h(-1) for 3,5-DTBCH2 under homogeneous conditions. The pyridine-containing complex demonstrates excellent recyclability over five cycles (<1.5% activity loss) due to its hierarchical porous morphology (SEM) and optimal surface charge (zeta potential = 19.5 mV). Kinetic stopped-flow studies reveal a two-step mechanism involving substrate binding followed by O-2 activation, with the thermodynamic driving force (Delta G degrees) for the 2Co & sup3;(+)/2Co & sup2;(+) couple being the key predictor of catalytic efficiency. Negative Delta G degrees values (-48.24 to -47.27 kJ mol(-1) V-1) for 3,5-DTBCH2 enable high activity, whereas positive Delta G degrees (45.63-47.56 kJ mol(-1) V-1) for 4-nitrocatechol suppresses quinone formation despite strong substrate binding. DFT-derived global reactivity descriptors (Delta E, eta, S, omega) successfully rationalize the experimental activity trend, establishing a predictive framework for designing efficient biomimetic oxidation catalysts.
Fossil fuel reserves depletion necessitates the generation of sustainable energy through hydrogen from water splitting, with efforts focusing on optimizing bifunctional electrocatalysts for improved efficiency. In this study the Fe-doped (1%, 5%, 10%) CoCu2Se4 mesoporous nanosheet array on a Ni foam substrate with varying concentrations using a hydrothermal synthesis. Fe doping in CoCu2Se4 lattice results in structural distortions and electronic modifications. The study discloses the insights of Fe+3 doping in CoCu2Se4 lattice sites lead to electronic modulation, improve conduction and catalytic mechanisms. Fe+3 higher electronegativity facilitates electron redistribution, modulating the band structure and reducing charge recombination losses. The study found that the optimized 5% Fe-doped CoCu2Se4 electrode demonstrated exceptional OER performance with a 216 mV of low overpotential along with a minimal 69.65 mV dec-1 Tafel slope. Additionally, remarkable HER activity having a minimal overpotential of 122 mV along with low Tafel slope up to 89 mV dec-1 was succeeded. Assembled device demonstrated exceptional stability for 40 h, indicating its potential for sustainable water splitting applications. Hence, for sustainable hydrogen production via water splitting, the Fe-doped CoCu2Se4 metals are a promising candidate.
The demand for clean water is rapidly growing, which has prompted further development of nanomaterials for environmental purification and biomedical research. Photocatalysis is a highly promising oxidation method for the removal of organic and biological pollutants. It is quite evident that there is a serious and pressing demand to design economic treatment techniques, which are cheap and energy independent. In this study, we described the fabrication of Z-scheme heterostructure Er doped ZrO2/Bi2WO6 that effectively enhances visible-light-driven charge separation and redox ability, leading to superior photocatalytic degradation and antibacterial performance. The dual-functionality and high mineralization efficiency demonstrated in this study highlight the potential of the developed photocatalyst for sustainable wastewater treatment and biomedical-related environmental applications. The composite and its constituents were synthesized by hydrothermal approach and characterized in terms of their structural, optical, functional, morphological, photocatalytic and antibacterial properties. The optimized Er-doped ZrO2/Bi2WO6 nanocomposite exhibited excellent photocatalytic performance, achieving 97.02% degradation of the moxifloxacin (MOX) drug under visible light and showed good antibacterial capability against four bacterial strains the order of Escherichia coli > Bacillus fortis > Staphylococcus aureus > Streptococcus canis. Reactive-species scavenging analysis proved that the role of superoxide radicals (center dot O-2(-)) and hydroxyl (center dot OH) plays a significant role in the photocatalytic degradation of MOX. The current study highlights the enhanced photocatalytic and antibacterial activity of the Z-scheme Er doped ZrO2/Bi2WO6 heterostructure due to their design and engineering, with applications in multifunctional industries, particularly environmental cleaning and biomedical research.
Workplace avoidance behavior represents a subtle yet pervasive form of employee disengagement that undermines continued performance and organisational functioning. Understanding how organizations can effectively curb such behavior remains an important yet underexplored issue in the human resource management (HRM) literature. Drawing on self-determination theory, this study examines how developmental human resource (HR) practices reduce workplace avoidance behavior. We propose that developmental HR practices indirectly reduce workplace avoidance behavior through two parallel mechanisms: the use of signature strengths and harmonious passion. Furthermore, we propose that developmental leadership functions as a boundary condition that strengthens the negative indirect effect of developmental HR practices on workplace avoidance behavior. Using a three-wave, multi-source research design, data were collected from 327 supervisor–subordinate dyads in service-sector organizations in China. The results provide empirical support for the proposed model. This study contributes to the developmental HR practices and avoidance behavior literature by illustrating the mechanisms by which developmental HR practices operate and highlighting the importance of HR–leadership alignment in reducing employee workplace avoidance behavior. Limitations and directions for future research are discussed.
