The photocatalysis research community is intensely focused on developing materials that offer a perfect blend of affordability, efficiency, and durability. Herein, novel hybrid Cu 2 FeSnS 4 -ZnO (CFTS-ZnO) hetero-structured nanocomposites in three different mass ratios and CFTS were designed by a microwave-assisted solvothermal method, while ZnO nanorods were synthesized via a hydrothermal method. The CFTS-ZnO (CFZN1, CFZN2 and CFZN3) nanocomposites, CFTS and ZnO were characterized for their crystal structure, surface morphology, and composition by XRD, HRSEM, TEM, and EDS, while UV–visible spectroscopy was employed to assess their optical properties and photocatalytic performance. XRD confirmed a tetragonal stannite crystal structure for CFTS, a hexagonal wurtzite crystal structure for ZnO and a mixture of hexagonal wurtzite and tetragonal stannite crystal structures for CFTS-ZnO (CFZN1, CFZN2 & CFZN3) nanocomposites. The average crystallite sizes were found to be 5.1, 54.9, 58.3, 51.3 and 56.4 nm for CFTS, ZnO, CFZN1, CFZN2 and CFZN3, respectively. Morphological analyses revealed nearly spherical morphology for CFTS, well-defined nanorods for ZnO, and uniformly anchored CFTS spheres onto the surfaces of well-defined ZnO nanorods for CFZN1, CFZN2 and CFZN3. The band gaps of CFTS, ZnONRs, CFZN1, CFZN2 and CFZN3 were found to be 1.47, 3.47, 2.51, 2.43 and 2.35 eV, respectively. The nanostructures were studied as photocatalysts for degrading malachite green (MG) dye under sunlight illumination. CFTS degraded about 54%, ZnONRs degraded about 51%, whereas CFZN1, CFZN2 and CFZN3 degraded about 47%, 58% and 98% of the initial MG dye within 120 min of exposure to sunlight. The photocatalytic degradation of MG proceeded via first-order kinetics, with rate constants (k) found to be 0.0071, 0.0060, 0.0048, 0.0067, and 0.0127 min − 1 for CFTS, ZnONRs, CFZN1, CFZN2 and CFZN3, respectively. The findings suggest that the nanomaterials, particularly the CFZN3 nanocomposites, are effective and economical photocatalysts for wastewater treatment, offering a promising solution for organic dye degradation.
The photocatalysis research community is intensely focused on developing materials that offer a perfect blend of affordability, efficiency, and durability. Herein, novel hybrid Cu2FeSnS4-ZnO (CFTS-ZnO) hetero-structured nanocomposites in three different mass ratios and CFTS were designed by a microwave-assisted solvothermal method, while ZnO nanorods were synthesized via a hydrothermal method. The CFTS-ZnO (CFZN1, CFZN2 and CFZN3) nanocomposites, CFTS and ZnO were characterized for their crystal structure, surface morphology, and composition by XRD, HRSEM, TEM, and EDS, while UV–visible spectroscopy was employed to assess their optical properties and photocatalytic performance. XRD confirmed a tetragonal stannite crystal structure for CFTS, a hexagonal wurtzite crystal structure for ZnO and a mixture of hexagonal wurtzite and tetragonal stannite crystal structures for CFTS-ZnO (CFZN1, CFZN2 & CFZN3) nanocomposites. The average crystallite sizes were found to be 5.1, 54.9, 58.3, 51.3 and 56.4 nm for CFTS, ZnO, CFZN1, CFZN2 and CFZN3, respectively. Morphological analyses revealed nearly spherical morphology for CFTS, well-defined nanorods for ZnO, and uniformly anchored CFTS spheres onto the surfaces of well-defined ZnO nanorods for CFZN1, CFZN2 and CFZN3. The band gaps of CFTS, ZnONRs, CFZN1, CFZN2 and CFZN3 were found to be 1.47, 3.47, 2.51, 2.43 and 2.35 eV, respectively. The nanostructures were studied as photocatalysts for degrading malachite green (MG) dye under sunlight illumination. CFTS degraded about 54%, ZnONRs degraded about 51%, whereas CFZN1, CFZN2 and CFZN3 degraded about 47%, 58% and 98% of the initial MG dye within 120 min of exposure to sunlight. The photocatalytic degradation of MG proceeded via first-order kinetics, with rate constants (k) found to be 0.0071, 0.0060, 0.0048, 0.0067, and 0.0127 min−1 for CFTS, ZnONRs, CFZN1, CFZN2 and CFZN3, respectively. The findings suggest that the nanomaterials, particularly the CFZN3 nanocomposites, are effective and economical photocatalysts for wastewater treatment, offering a promising solution for organic dye degradation.
Anxiety disorders are associated with prefrontal dysfunction, yet their impact on neural mechanisms underlying skilled motor learning remains poorly understood. We examined movement-readiness potentials (MRPs) using electroencephalography during a visuomotor adaptation task in 31 young adults (13 with clinically diagnosed anxiety disorders, 18 controls). MRPs were analyzed across three temporal components: early motor preparation (− 1500 to − 500 ms), late motor preparation (− 500 to − 100 ms), and movement execution (− 100 to + 100 ms). Individuals with anxiety disorders showed significantly reduced MRP amplitudes during late motor preparation (p = 0.033) and movement execution (p = 0.047) compared to controls, while early motor preparation remained intact. Despite these neural alterations, both groups demonstrated equivalent behavioral performance, with similar learning and retention of a visuomotor rotation task. Anxiety disorders selectively disrupt late-stage cognitive-motor integration processes during movement preparation and execution. The dissociation between impaired neural activity and preserved behavioral performance suggests compensatory mechanisms that maintain motor learning despite underlying neural inefficiencies. These findings reveal that anxiety affects integrated systems of cognition and action, providing new insights into their functional neurophysiological impact.
Efficient, effective, and equitable disaster response is critical yet challenging due to uncertainties, particularly those in vehicle travel times caused by infrastructure damage. To address this, current study proposes a scenario-based robust optimisation social cost vehicle routing problem (SRO-SCVRP) that minimises three objectives: (1) social cost, balancing logistics and deprivation costs, with the latter quantifying survivors' suffering from delayed access to critical supplies; (2) the variation in expected deprivation cost across travel time scenarios, reflecting solution robustness; and (3) penalties for exceeding service coverage windows (SCW), which are thresholds set by decision-makers to ensure timely deliveries, thereby enhancing model robustness. Logistics and deprivation costs operationalise efficiency and effectiveness, respectively, while the second and third objectives promote equity by reducing disparities in access and ensuring the timely fulfilment of demand. Numerical results from the SRO-SCVRP highlight a trade-off wherein gains in robustness and equity are achieved with only a modest impact on logistics cost. To assess robustness and equity, a Time and Inventory Service-Level Metric (TISM) is developed and applied to alternative water distribution strategies. Among them, the hybrid strategy yields the highest overall TISM, making it the most robust and equitable option across varied SCW thresholds and resource availability.
.-Precise demographic data are needed to model population dynamics, design management and recovery strategies, and answer questions in ecology and evolution, but for many species, accurate information on age and frequency of reproduction is lacking. Using data from a 10-year capture-mark-recapture study, I describe demographic analyses of sympatric populations of three natricine snakes, Dekay's Brownsnakes (Storeria dekayi), Red-bellied Snakes (S. occipitomaculata), and Common Gartersnakes (Thamnophis sirtalis), focusing on age and frequency of reproduction. I examined cloacal smears from males for sperm and palped females for enlarged follicles and embryos to infer minimum size at maturity and used logistic regression to relate sperm positivity and gravidity to size. I determined minimum age of maturation and first reproduction from known-age von Bertalanffy growth equations. I estimated female reproductive frequency from reproductive histories, proportion gravid, and relationship between size and gravidity. Using this information, I constructed matrix projection models to compare the effect of accelerated or delayed reproduction on the population growth parameter, ). In all three species, a small proportion of females reproduced when just one year old but for most females, and for males, age of first reproduction was 2 years. Accelerating reproduction by a year resulted in rapid population growth (lambda = 1.08-1.18), and delaying reproduction resulted in rapid population decline (lambda= 0.86-0.91) relative to baseline (lambda= 1.00). Further quantification of demographic traits and associated trade-offs could improve population projection models and provide a clearer understanding of life history variation.
