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Synergistic VO and VN dual vacancies in homometallic Co3O4/CoN heterojunction boosting built-in electric field for efficient hydrogen production
Feng, Yufa; Tian, Jingjing; Shao, Youxiang; Dyosiba, Xoliswa Lindokuhle; Ren, Jianwei; Xiong, Jiageng; Gao, Qingsheng; Li, Hao (Elsevier, 2026-02)
Please read abstract in the article.
A carbon subsidy framework for coordinated low-carbon operation in industrial park with multiple users
Ren, Zhiling; Chen, Xi; Zhao, Boya; Dong, Yun (Elsevier, 2026-05)
As the global impacts of carbon emissions intensify, power markets are shifting from profit-driven models to frameworks that integrate economic performance and carbon mitigation. Current low-carbon approaches commonly exhibit insufficient user response, elevated abatement costs, complex implementation, and limited flexibility. To bridge this gap, we propose a carbon subsidy framework for industrial parks. In this framework, the Industrial Park Operator (IPO) announces real-time shared electricity, carbon, and subsidy prices, while users optimize load scheduling and market participation. The interaction is formulated as a Stackelberg game and solved using a Differential Evolution-Mixed-Integer Quadratic Programming (DE-MIQP) approach. Case studies demonstrate that, compared with a baseline without subsidies, the IPO provides a total subsidy of 1,295.57 CNY, the proposed framework reduces industrial-park CO2 emissions by 40.13 %, and the IPO’s profit decreases by 217.39 CNY, while the users’ aggregate profit increases by 608.3 CNY. Finally, two sensitivity analyses are conducted: one investigates parameter sensitivity, and the other is a ten-user case study that exhibits emission-reduction behavior similar to that of the four-user case. These findings confirm that the carbon subsidy framework effectively incentivizes user participation, reduces emissions, and offers a practical pathway for coordinated low-carbon operation in multi-user industrial parks. HIGHLIGHTS • Carbon subsidy framework for coordinated low-carbon industrial park operation. • Stackelberg game with DE-MIQP preserves user privacy while finding equilibrium. • Subsidy cuts park CO2 emissions by 40.13 % and SPP output by 47.01 % versus baseline. • Profit shifts: IPO -217.39 CNY, users +608.3 CNY, subsidies total 1,295.57 CNY. • Sensitivity and ten-user studies confirm robustness and scalability of the scheme.
DNA barcoding and anti-tyrosinase activities of three species-representative populations of the genus Greyia Hook & Harv
Botha, Ine; De Canha, Marco Nuno; Oberlander, Kenneth Carl; Botes, Jana; Lall, Namrita; Berger, David Kenneth (Elsevier, 2026-02)
The tree genus Greyia is endemic to South Africa and Eswatini. The Eastern Cape species Greyia flanaganii Bolus is confined to a limited range west of the Kei River. Greyia radlkoferi Szyszyl. occurs in Limpopo Province, whereas Greyia sutherlandii Hook. & Harv. is associated with KwaZulu-Natal Province, but the ranges of these two species overlap in Mpumalanga Province. Greyia trees are of value to the bioeconomy as leaf extracts from G. flanaganii and G. radlkoferi possess anti-tyrosinase activity and low toxicity and are being developed in herbal formulations for the treatment of skin hyper-pigmentation. The main active compound is 2’,4’,6’ trihydroxydihydrochalcone. However, there are no reports of medicinal assays from Greyia trees growing in their natural habitat, it is not known whether the third species - G. sutherlandii - has activity, and DNA barcode data is limited. To address these knowledge gaps, we sampled five trees per Greyia species that matched morphological descriptions and were from sites close to type specimen collection records. Leaf ethanolic extracts from G. sutherlandii had similar average anti-tyrosinase activity (IC50 = 84 µg/mL ± 18 [SD]) when compared to G. radlkoferi (58 µg/mL ± 21) and G. flanaganii (72 µg/mL ± 11). High Performance Thin Layer Chromatography showed the presence of the active compound in all three species, although it was below the detection limit of 4.4 µg/10 mg extract in two of the G. flanaganii samples. Considering the difficulty in differentiating G. sutherlandii from G. radlkoferi morphologically in the field and production orchards, we investigated DNA barcoding as a method of species-specific authentication. Phylogenetic analysis using Bayesian Inference from combined ITS, trnL-F, matK and psbA-trnH barcodes from the 15 Greyia trees plus Genbank sequences indicated (i) clear differentiation from other lineages in the order Geraniales, but (ii) extremely short internal branches within Greyia and poor discrimination between Greyia species and individuals. Our study has shown that natural populations of all three species sampled in late summer exhibit consistent leaf anti-tyrosinase activity between biological replicate trees. We have demonstrated activity from G. sutherlandii for the first time, indicating that this species can also be deployed in production orchards. However, alternative phylogenetically informative SNP markers need to be developed to provide species-specific authentication of Greyia extracts in herbal products. HIGHLIGHTS • First report of anti-tyrosinase activity of leaf extracts from wild-growing Greyia spp. • Greyia sutherlandii leaf extracts shown to have anti-tyrosinase activity for the first time. • HPTLC method developed to quantify the active compound 2′,4′,6′-trihydroxydihydrochalcone. • DNA barcoding (ITS, matK, trnL-F, psbA-trnH) conducted on core populations of three Greyia spp. • DNA barcode phyogeny discriminates Greyia spp. from other Geraniales genera. • G.sutherlandii and G.radlkoferi not resolved phylogenetically with DNA barcodes. • G. sutherlandii and G. radlkoferi hard to differentiate in the field morphologically.
Adsorptive removal of Carbamazepine from synthetic wastewater using Moringa oleifera seed coat
Azeh, Peace S.; Jimoh, Monsurat Omolola; Masitha, Mabafokeng; Iwarere, Samuel Ayodele; Daramola, Michael Olawale (Elsevier, 2026-01)
Biosorption has demonstrated effectiveness in eliminating contaminants of emerging concern (CECs) that lack inclusion in current water quality standards. These pollutants impede progress towards UN Sustainable Development Goals 6 and 14, pertaining to clean water accessibility and marine life preservation. This research investigated the adsorption potential of the persistent pharmaceutical pollutant, carbamazepine, using Moringa oleifera (MO) seed coat. This research investigated the adsorption potential of the persistent pharmaceutical pollutant, carbamazepine, using MO seed coat biochar. Acid hydrolysis and subsequent carbonization produced a biochar with superior properties for adsorption as confirmed by FTIR, SEM, EDX, CHNOS, and XRD analyses. The influence of agitation speed (200 rpm, 300 rpm, and 400 rpm), adsorption duration (0 to 180 min), and adsorption temperature (30 °C, 40 °C, and 50 °C) on CBZ removal in synthetic wastewater were studied. The quadratic regression model obtained from Box Behnken experimental design (BBD) with Response surface methodology (RSM) showed a strong predictive ability with R² = 0.9754 and adjusted-R² = 0.9015. Agitation speed significantly influenced the adsorption capacity as evidenced by a p-value of 0.02848. The optimum conditions for CBZ adsorption were 400 rpm, 30 °C, and 2.15 h at which a maximum adsorption capacity of 51.87 mg/g was anticipated. The adsorption behaviour was best described by pseudo-second order kinetics and the Temkin isotherm model. The study confirmed that MO seed coat biochar as a promising green adsorbent for pharmaceutical contaminant removal in wastewater treatment. HIGHLIGHTS • Adsorption of carbamazepine (CBZ) by Moringa Oleifera seed coat biochar is presented. • Acid hydrolysis with 85 % H3PO4 followed by carbonisation increased the surface area from 1.160 m2/g in the raw biosorbent to 237.3 m2/g in the biochar. • 93.3 % of CBZ was removed from 50 ppm solution within 3 hours of agitation at 200 rpm. • Agitation speed significantly affected adsorption capacity for CBZ unlike adsorption temeprature and time • Pseudo second-order kinetics and Temkin isotherm model adequately described the adsorption of CBZ on MO.
Uncovering cultural regularities underpinning the pedagogy of learners with disabilities
Kumador, David Kwame; Muthivhi, Azwihangwisi Edward (AOSIS, 2026-01)
BACKGROUND : Fear of disability tends to influence teachers’ pedagogical practices in early childhood education in Ghana. Deeply rooted in socio-cultural beliefs, this fear hinders inclusive education and perpetuates exclusionary practices. AIM : This article explores the fear of disability within Ghanaian early childhood education, as an instance of Ghanaian and West African cultural practices manifesting in and through teachers’ classroom activities, which constrain the effective learning and development of learners with disabilities. Setting: The research was conducted with teachers from seven early childhood education centres in Accra, Ghana. METHOD : We applied focus group interviews, integrating a local conversational approach to enhance the effectiveness of our Vygotsky-inspired authentic questioning method. Using an approach that embodies respect, mutual acknowledgement, and affirmation of each other’s humanity, the first author was able to uncover the profound cultural meanings of the teachers’ practices, which would otherwise have been difficult to reveal through a rigid application of formal methods. RESULTS : The findings promote cultural contingency of methods as tools for uncovering the dynamic structure of cultural processes, such as fear of disability, that underpin complex social practices of the pedagogy of learners with disabilities. CONCLUSION : The article provides an analysis of the data and the process through which data was produced, leading to the uncovering of the underlying culturally situated regulatory processes vis-à-vis the teachers’ relationship with learners with disabilities. CONTRIBUTION : The paper contributes to the application of informal methods of inquiry, informed by both theory and practice in cultural psychology and education.