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Adsorption performance and mechanism analysis of hydrotalcite derived CaFe-bimetal materials for highly efficient Cd<sup>2+</sup> removal process from kinetic and isotherm aspects
Get PDFThe removal of toxic and soluble Cd2+ is facing challenges in developing low-cost materials with retention stability and high capacity. To solve this problem, the CaFe-bimetal hydrotalcite (LDH) and its oxide (LDO) were adopted due to their integrated excellent ion exchange and isomorphic substitution property. The influencing factors, including Ca/Fe mole ratio, calcination temperature, the initial Cd2+ concentration and the adjustable ion kinds, were considered to obtain better adsorption performance. Similar ion size of Ca2+ and Cd2+ and the calcined LDOs with expanded channels promoted the Ca2+ dissolution and the mass transfer of Cd2+ entering into the laminate, and thus the isomorphic substitution sufficiently improved the high efficiency of Cd2+ removal of about 1079 mg/g in 20 min with Ca4Fe1-LDO-300. Based on the characterization and DFT results, LDOs exposed more active sites and enhanced the isomorphic substitution of Cd2+ for Ca2+ process. The thermodynamic and kinetic results revealed that the abundant –OH sites in hydrotalcite were beneficial for Cd2+ removal through surface adsorption, electrostatic attraction, and other interactions. The obtained adsorption mechanism offers guidance for the highly efficient Cd2+ removal in an aqueous solution system.</p
The Dynamic Response of Ti521, a Titanium Alloy for Impact Containment:Rate Dependency and the Influence of Cooling Processes
Get PDFTi521, a titanium alloy with a tailored composition that provides an excellent balance of strength and ductility, was developed and manufactured. The effects of cooling rate on both quasi-static and dynamic mechanical behaviour were investigated. An extensive experimental campaign was undertaken to characterise the rate dependent properties of Ti521 and to evaluate the influence of manufacturing parameters on its mechanical performance. The alloy exhibited the highest yield strength under rapid cooling conditions, with values exceeding those of Ti6Al4V. Furthermore, the analysis of the energy dissipated during plastic deformation indicates that Ti521 has strong potential to outperform Ti6Al4V in impact containment applications.A novel experimental methodology, incorporating multiple camera setups, was introduced and employed to characterise anisotropy induced by variations in cooling rates and rolling directions. This approach enabled the accurate evaluation of the true stress-strain response in the presence of anisotropy and, consequently, the influence of rolling direction on the mechanical performance of the alloy. Cross rolled specimens exhibited no measurable anisotropic behaviour, whereas unidirectionally rolled material showed slight differences in mechanical properties between the rolling and transverse directions
Experimental assessment of stiffening geometries for thin-walled structural steel plates made by wire arc additive manufacturing
Get PDFAn innovative strategy of imposing geometric sinusoidal waves has been proven effective in enhancing the local buckling resistance of steel plates made by selective laser melting (SLM). However, its efficiency on wire arc additively manufactured (WAAM) steel, which is a more economically and environmentally viable alternative, remains unexplored, particularly given the manufacturing defects such as material anisotropy and geometric inaccuracy associated with WAAM. This work presents an experimental investigation into the stiffening effect of sinusoidal wave patterns on WAAM-fabricated steel plated sections. Stub column tests and geometric measurements were conducted on square hollow sections (SHS) and I-sections fabricated in 316 L stainless steel. The specimens incorporated the sinusoidal wavy geometries previously validated in equal-leg angle sections under external plate boundary conditions. The present study extends their application to internal plate elements in SHS stub columns and examines the combined behaviour of internal and outstanding plate elements in I-sections with sinusoidal stiffening. The obtained results demonstrate a normalised strength enhancement of up to 9% with equal or even less material consumption (0.2% to -4.5%). Comparisons are made with conventionally manufactured and existing WAAM-fabricated stainless steel plated elements, as well as with current Eurocode 3 design equations and provisional design rules proposed for SLM-fabricated stiffened plates. Based on the findings, design recommendations for such structures have been made.</p
Teacher agency in practiced language policy in higher education in East and Southeast Asia (2010–2025):A systematic review
Get PDFThis paper presents the first systematic review connecting Teacher Agency (TA) and Practiced Language Policy (PLP) in English-medium instruction (EMI) within higher education (HE) across East and Southeast Asia. Following the PRISMA protocol, the review included twenty empirical studies published from 2010 to early 2025. Patterns of TA development and the pathways supporting them were identified through visualized co-occurrence. Findings show that agency is developmental and shaped by institutional arrangements, professional learning, and identity commitment. Classroom outcomes play a critical role in informing TA when implementing translanguaging, reassessing program and institutional contexts. A 3 × 3 Integrated Model was proposed viewing PLP as Context, TA as Action, and practiced policy as Outcomes across macro, meso, and micro levels. This model provides actionable insights for optimizing resource allocation at critical decision points, granting contextual autonomy at the program level, and integrating professional development with the cyclical process of policy interpretation, reframing, and enactment.</p
Marine soundscapes of the Arctic and human impacts:going beyond the “shipping bands”
Get PDFIn the Arctic, amplified climate change enables increased human activity, adding to sounds in the ocean. Future guidelines need to know local baselines and how best to measure anthropogenic impacts. The EU Marine Strategy Framework Directive uses “shipping bands”, third-octave bands centred on 63 Hz and 125 Hz. Addressing the lack of measurements, acoustic models often use satellite recordings of ship tracks, We investigate sound levels in Cambridge Bay (Nunavut, Canada) between 2015 and 2024, comparing May (full ice cover, no shipping) and August (little to no ice, shipping activity). We show “shipping bands” should include frequencies up to several kHz and sounds include snowmobiles, aircraft and small vessels untracked by satellites. This will need addressing in future guidelines. This is particularly important because of the development of Arctic shipping routes, increasing resource exploration and tourism, amplified by current plans for the expansion of mining, drilling and other geostrategic pressures
An intelligent data-driven flow regime recognition method for horizontal air-water two-phase flow
Get PDFFlow regime recognition is very important in the two-phase flow measurement. However, considering that two-phase flow is much more complicated than single-phase flow, flow regime cannot be accurately identified by mechanism model. In this work, a novel intelligent data-driven method based on image encoding and transformer is proposed to recognize typical flow regimes encountered in the horizontal air-water flow. Dynamic experiment is carried out using a ring-shaped conductance sensor to collect voltage signals of bubble flow, bubble-slug flow, slug flow, slug-stratified flow and stratified flow. To highlight the characteristic differences between different flow regimes, the measured signals are encoded into two-dimensional images. To classify the encoded images of the five flow regimes, transformer models are then established. With the encoded images as the input of the model, flow regime identification is implemented by training of the model. The results demonstrate that the characteristics of different flow regimes can be better reflected in the encoded image with Gramian angular field. Meanwhile, the recognition accuracy of Swin Transformer is advantageous to that of Vision Transformer in the classification of the encoded images of the five flow regimes. Comparing with other identification methods, the method which combines Gramian angular field with Swin Transformer shows the best performance in the recognition of the flow regimes. The total accuracy reaches as high as 99.1 % This study offers an alternative for accurate flow regime recognition in two-phase flow measurement
Dataset for "Influence of Block Microstructure on the Interaction of Styrene-Maleic Acid Copolymer Aggregates and Lipid Nanodiscs"
No full textCopolymers between styrene and maleic acid are able to extract membrane proteins directly from cells, reconstituting lipid membranes into nanodiscs. RAFT copolymerisation was used to generate copolymers of equivalent molecular mass but inverted block sequences and end group termini. This dataset contains characterisation data for the copolymers (GPC, NMR, FTIR, UV-vis), included deuterated variants for neutron scattering experiments, as well as the structures formed in solution. Aggregates were assed by a combination of DLS and surface tension measurements, and nanodisc formation kinetics through UV-vis using both model DMPC vesicle and E.coli membrane suspensions. It was found that mismatched hydrophilic and hydrophobic end groups on the respective styrene block and alternating block, impeded membrane solubilisation. This highlights not only how the amphiphilic balance of these blocks is important for efficient nanodisc formation, but also how end groups influence these and may be optimised towards the extraction of more challenging MPs
Procurement Scheduling for Assemble-to-Order Systems
Get PDFDue to the increasing complexity and diversity of customer demand, assemble-to-order (ATO) systems should account for more realistic factors in their procurement decisions. The classical literature offers analytical elegance but oversimplifies reality. This study bridges this gap by developing a multiperiod procurement problem for multi-product ATO systems under scenario-based demand uncertainty, considering realistic factors like varying product prices, bill of materials (BOM) structures, multiple suppliers with different lead times and costs, and contract options provided by suppliers with different discount prices. A multi-stage stochastic programming model is formulated to maximize the profit ofthe ATO system by optimally making decisions on (i) pre-stocked inventory, (ii) supplier selection, (iii) contract signing with options, and (iv) assembly planning. To solve the model efficiently, we propose an exact Benders decomposition algorithm with tailored subproblem (SP) relaxation, valid inequalities, and Pareto-optimal cuts. Experiments based on real data validate the exact algorithm’s effectiveness. For large-scale instances, the proposed algorithm improves the objective value by 13.7% over Gurobi’s best-found solution within a one-hour time limit. To further accelerate the algorithm, we introduce an efficient scenario reduction method based on forward-looking distance matrices. The proposedreduction method is proven to be more effective than traditional approaches, improving solution quality by up to 15.4% while accelerating computation by a factor of 3.5. This study also provides managerial insights for contract design, pre-stocking strategies, and supplier selection. For example, decisionmakers should negotiate with suppliers for more contract options in volatile markets, prioritize slow suppliers while maintaining a pool of fast suppliers as backups, and increase pre-stocked inventory for those with high and very high commonality
Mafia Expansion: The 'Ndrangheta in Established Democracies by Z. L. Hauser Oxford, Oxford University Press, 2025, 288 pp., £100 (hardback), ISBN: 9780198895541
Get PDFEffective acid recovery from rare earth stripping solution by diffusion dialysis
Get PDFThe consumption of substantial alkali and emission of high-salinity wastewater during the precipitation step of stripping solutions in rare earth (RE) element extraction processes remain critical challenges. This study proposes an energy-efficient and environmentally benign diffusion dialysis (DD) process for separating H+ and rare earth ions (RE3+) in simulated rare earth stripping solutions. Six commercial anion exchange membranes (AEMs) were first evaluated for separating RECl3/HCl mixtures. The dense AEM with single polyethylene terephthalate string structure (M6) demonstrated the optimal DD performance for H+ and RE3+ separation. Among three typical RE3+ ions with different radii (i.e., Y3+, La3+, and Yb3+), the M6 AEM exhibited the lowest selectivity between H+ and La3+, which is correlated with the higher tendency of La3+ hydrated ions to dehydrate during transmembrane transfer. Under optimized operation conditions (feed solution: 0.2 mol L−1 HCl and 0.25 mol L−1 La3+), the DD process using the M6 AEM achieved an H+ recovery rate of 69.77 % and a La3+ leakage rate of 0.05769 % with a H+/La3+ selectivity of 5519.2. Importantly, the M6 AEM maintained consistently stable DD performance for separation of H+ and RE3+ ions over a 30-cycle consecutive operation in the stimulated rare earth stripping solution containing typical organic pollutants (i.e., P507 and sulfonated kerosene), showing an impressive antifouling property. This study provides an insightful guideline for practical acid recovery from the rare earth stripping solutions.</p
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