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A Supply-demand Evaluation Framework for Uncovering Age and Gender Inequities in Urban Green Space Cooling- A Case Study of Fuzhou
No full textRapid urbanization and intensified urban heat island effects have increased the need for effective, equitable cooling strategies. Urban green spaces (UGS), as nature-based solutions, provide critical cooling benefits that support thermal comfort and enhance urban resilience. However, disparities in cooling needs and access persist across gender and age, with vulnerable populations often facing unequal access to UGS resources. Despite growing attention to UGS equity, methods for quantifying demographic-specific mismatches between cooling supply and population demand remain underdeveloped. To address this gap, we developed a supply–demand evaluation framework to examine spatial equity and age- and gender-related environmental injustices in UGS cooling benefits in Fuzhou, China. The results show: 1) UGS cooling benefits supply and demand exhibit broadly similar spatial patterns across demographic groups but divergent patterns between the urban center and periphery. 2) Fuzhou’s main urban area faces pronounced supply–demand mismatches, with elderly and female populations more affected by uneven resource distribution. 3) Significant disparities (p < 0.001) exist across age and gender groups, with children and middle-aged adults experiencing greater mismatches, while men face more severe supply deficits. Although UGS spatially favors vulnerable groups, substantial inequities in cooling access remain. Notably, targeted planning and management strategies were proposed for urban and green space systems, tailored to different population groups and types of supply–demand mismatch. This study highlights the urgent need for age- and gender-responsive UGS planning and offers a transferable approach to reduce cooling inequalities, supporting more equitable and climate-resilient urban environments
Synthesis of new metal oxide sensing materials via the HMT technique for humidity control in the pharmaceutical industry
No full textStringent humidity control is required in the pharmaceutical industry to maintain product stability and prevent adverse impact on drug quality. Exposure to extreme humidity conditions can cause microbial contamination and loss of therapeutic properties of drug products. Various regulations have been established by organizations such as the World Health Organization (WHO), the Food and Drug Administration (FDA), and the US Pharmacopeia (USP) to ensure humidity control stays within defined ranges. Humidity sensing is crucial for maintaining optimal conditions in healthcare facilities, production lines, and sterile storage. Conventional humidity sensing is facing limitations in sensitivity, stability, and measurement range. The hygroscopic materials improve the humidity sensing performance with increased surface area, providing more active sites for water molecule adsorption. This paper explores the synthesis of a novel metal oxide sensing material using hexamethylenetetramine (HMT) and examines the hygroscopicity of the synthesized sensing material. In the study, tin dioxide (SnO2) and zinc oxide (ZnO) were synthesized via the low-temperature hydrothermal method with and without additive-enhanced technique. The sensing materials were evaluated for its potential in humidity sensing improvement by conducting a hygroscopicity test and the linear equation was analyzed to compare the slope of mass uptake ratio under incremental and decremental relative humidity (RH). The result demonstrated humidity sensing enhancement can be achieved with the presence of HMT due to the porous structure and hydrophilic nature. From the hygroscopicity test result, the slope of ZnO-HMT was ~ 2x higher compared to ZnO, while SnO2-HMT was ~ 3x higher compared to the SnO2 counterpart. This result suggests that the additive-enhanced sensing material has the potential for improving humidity sensing in pharmaceutical applications, offering a promising solution for humidity optimization across the industry
Construction and mobility analysis of networks of deployable even-sided equilateral polygons
No full textDeployable planar mechanisms represent a classical category of deployable systems with broad applications in civil engineering, space exploration, metamaterials, and beyond — either as standalone structures or as compositional units. Despite significant progress in recent decades, designing such mechanisms remains challenging due to their overconstrained nature. This paper addresses the construction and mobility analysis of networks of deployable even-sided equilateral polygons (NDEEPs). Two approaches are proposed: the link-connection method and the joint-connection approach. Three classes of one degree-of-freedom (DOF) NDEEPs and one class of 2-DOF NDEEPs are introduced. Since conventional formulas for the mobility analysis are not applicable to NDEEPs derived via the link-connection method, a mobility analysis method based on a minimal set of constraint equations is proposed. The geometric characteristics of these NDEEPs are also identified. Two classes of NDEEPs derived from tessellations differ fundamentally from hinged tessellations. Additionally, two novel tessellations composed of three types of semi-regular equilateral polygons are discovered as a by-product. This work complements existing research on expanding polygon arrays, hinged tessellations, and deployable networks, contributing to the broader study of overconstrained mechanisms
The Effect of Sewer-Derived Airflows on Air Pressure Dynamics in Building Drainage Systems
No full textThe performance of a building drainage system, “BDS”, is determined by the complexity of internal airflow and pressure dynamics, governed by unsteady wastewater flows from randomly discharging appliances such as WCs, sinks, and baths. Designers attempt to optimise system safety by equalising pressure and incorporating ventilation pipes and active devices such as AAVs and positive pressure reduction devices (PPRDs). However, failures within these systems can lead to foul gases and potentially hazardous microbes entering habitable spaces and posing a risk to public health. This study, for the first time, develops a novel model that simulates the effect of air from the sewer on BDS performance, which describes the correlation between system airflow and air pressure under the influence of air from the sewer. A combination of full-scale laboratory experiments representing a 3-storey building and real-world data from a 32-storey test rig configured as a building demonstrated that sewer air significantly modifies airflow and air pressure within a BDS. These findings are crucial for modern urban environments, where the prevalence of tall buildings amplifies the risks associated with air pressure transients. This work paves the way for updating codes to more effectively address real-world challenges
Resource recovery and water reclamation from acid mine drainage: Market analysis, industry trends, and future research directions
No full textAcid mine drainage (AMD) is a highly recalcitrant wastewater matrix that is typically generated from coal and metal mining activities and contains elevated levels of (heavy) metals and sulfates, along with rare earth elements (REEs) and radionuclides in some instances. This review seeks to elucidate the physicochemical characteristics of AMD and potential resource recovery avenues that can grossly underpin circularity and introduce the waste-to-resource paradigm. Specifically, opportunities for major metals (e.g., iron (Fe), aluminum (Al), and manganese (Mn)) and critical minerals, such as cobalt (Co), nickel (Ni), and notably, REEs recovery, along with other minor constituents, such as radionuclides, were explored. Other valorization avenues, such as sulfates transformation to sulfuric acid and recovery, and water reclamation were further explored. The techniques for resource recovery from AMD, such as precipitation, adsorption, solvent extraction, and ion exchange, were discussed, as well as possible industrial uses of the recovered materials (e.g., coagulants, adsorbents, pigments and catalysts). The beneficiation and valorization of AMD can minimize ecological footprint associated with this notorious mine water effluent, and, to a larger extent, reduce the extraction of virgin resource, such as REEs, while water reclamation can provide water security in water-scarce regions and countries. The recovered resources can provide an important revenue stream by offsetting the treatment costs and even making the process self-sustainable due to the high value of certain products. For example, the REEs global market in 2023 was USD14.2 billion by 2033, with a compound annual growth rate (CAGR) of 12 %, thus denoting that recovering REEs from AMD could be profitable, while it also reduces mining requirements and associated environmental impacts. Finally, knowledge gaps in terms of recoverability, along with challenges, prospects, and avenues for further research into this growing field were also distilled
Commercial and Purified Phosphonate Scale Inhibitors in Carbonate Systems: Retention, Release, and Supernatant Reactivity
No full textThis paper describes a study of the interactions of diethylenetriamine penta(methylene phosphonic acid) (DETPMP), one of the most widely used phosphonate scale inhibitors (SIs), with carbonate substrates. Much previous work has appeared on this topic, but here, we present results addressing key gaps identified in earlier studies. The experimental program focused on four main areas: (i) static adsorption/compatibility analysis of DETPMP at both 95 and 21 °C. Static tests revealed that SI retention mechanisms are significantly more active at elevated temperatures compared to 21 °C, where only minimal adsorption was observed. At 21 °C with initial pH0 = 4, calcite dissolution occurs, and Ca2+ may interact with DETPMP, but precipitate formation is minimal. The SI’s concentration primarily governs pH behavior under these conditions. The experimental results presented here provide data to validate computational modeling work reported in a separate study (Kalantari Meybodi et al., Colloids Surf. A Physicochem. Eng. Asp. 2024, 133535). (ii) Precipitation and re-dissolution tests of DETPMP_Ca complexes, which were conducted across a temperature range of 21–95 °C, with a subsequent larger-scale test at 95 °C. For systems with high [Ca2+], the smaller-scale experiments yielded similar masses of precipitate (post-filtration and oven-drying) across all temperatures. The stoichiometries of the DETPMP_Ca complexes formed were determined using two methods: direct analysis of redissolved precipitates in distilled water/HCl and indirect measurement of Δ[Ca] and Δ[DETPMP] from supernatant solutions, both using Inductively Coupled Plasma-Optical Emission Spectroscopy (ICP-OES). The stoichiometric analysis revealed that the excess [Ca2+] and initial pH of 8.5, rather than temperature, governed the reaction, almost achieving maximum complexation (5 ligands) between Ca2+ and DETPMP in solution. The precipitates were characterized using ESEM-EDX and thermogravimetric analysis (TGA). ESEM-EDX surface imaging and compositional analysis demonstrated that the complexes had amorphous structures under all temperature conditions, while TGA results showed that the complexes had decreasing water content with increasing preparation temperature. (iii) The purified SIs obtained at 95 °C were used to examine how removing phosphorus-containing impurities affects inhibition and adsorption performance. A series of inhibition efficiency (IE) and static adsorption experiments compared purified and commercial DETPMP. Their effectiveness in preventing BaSO4 precipitation was assessed by measuring Δ[Ba2+] before and after the addition of DETPMP to the brines using ICP analysis. Results demonstrated that purified materials exhibited very similar barium sulfate inhibition efficiency to commercial products, indicating that the impurities did not significantly influence the inhibition process. Comparative adsorption studies revealed higher apparent adsorption values for purified DETPMP, attributed to the impurities in the commercial products being measured as active DETPMP concentrations despite not participating in the adsorption process. It is shown how this can easily be corrected and accounted for in our results. (iv) The supernatant solution from the DETPMP_Ca complexation process was analyzed following initial precipitation. The effectiveness of this supernatant solution was then evaluated for BaSO4 scale inhibition. The results indicated that these residuals showed almost no efficiency in inhibiting BaSO4 formation. Subsequently, precipitation experiments were conducted to further investigate the complexation and precipitation behavior of the supernatant materials, revealing that only small amounts of DETPMP_Ca complexes were actually present; i.e., the relatively high apparent “DETPMP” concentration was mainly (P-containing) impurity and not DETPMP
Corporate governance characteristics, shareholder dissent and agency cost of debt
No full textWe examine how shareholder dissent both affects and is affected by agency cost of debt, using credit ratings as a proxy. Specifically, we explore (1) whether agency costs of debt trigger dissent differently across corporate governance regimes characterized by greater stakeholder collaboration versus those with stronger shareholder dominance, and (2) whether credit rating agencies' subsequent responses to dissent vary across these regimes. We find evidence that dissent is lower when ratings are higher, but there is limited evidence that shareholders in more collaborative regimes dissent more. Dissent tends to improve subsequent credit ratings when shareholders are highly dominant, but this effect diminishes in more coordinated governance systems. This evidence suggests that dissent shifts power toward shareholders, which is more costly to debtholders in governance systems that are based on collaboration among stakeholders
Switching cost and cognate facilitation between two signed languages
No full textThis study investigated language switching and cognate facilitation in deaf bilinguals fluent in two signed languages—Irish Sign Language (ISL) and British Sign Language (BSL). Ten participants, who were all deaf and were educated in ISL and later exposed to BSL, completed a picture-naming task requiring them to switch between the two languages based on visual cues. The study aimed to establish whether a switching cost—typically observed in unimodal spoken language bilingualism—also exists in unimodal signed language bilingualism, and whether language dominance and cognate status mediated this effect. Results confirmed a general switching cost: participants were slower to respond on switch trials than during a baseline block with no switching. Both language dominance and cognate status affected the switching cost, such that switching costs were greater in the dominant language, and non-cognates were significantly slowed by switching but cognates were not. Accuracy rates were high and did not vary significantly by switching condition or language. As the first investigation to provide evidence of a switching cost in deaf bilinguals who use two signed languages, this study provides an important foundation for future work exploring how language modality and language ecology shape the cognitive control systems underlying language switching
Complete dynamic model of a Slinky based on torsion springs
No full textIn this paper a dynamic torsion spring model is extended to be applicable to Slinky's with a wide range of possible initial configurations. In the extended model the coil-on-coil impact is modelled by conserving momentum and modelling the impact as an inelastic impact with a zero coefficient of restitution. The extended model is applied to a plastic Slinky and a steel Slinky. The extended model is demonstrated to have the qualitatively correct dynamic behavior. The extended torsion spring model is now in a form to be applied to a wide range of Slinky behavior such as pseudo-levitation, wave propagation phenomena and stair walking
Collapsed European oyster reefs must be restored at ecosystem scales
No full textEuropean native oyster (Ostrea edulis) reef ecosystems are collapsed but were once a dominant feature of European seascapes. Recent restoration efforts, while increasing, remain diminutive compared to the ecosystem's former extent and what is required to restore functioning oyster reef ecosystems. A functioning European native oyster reef ecosystem requires larval connectivity at the metapopulation scale to ensure sustained recovery of resilient oyster reef ecosystems and biodiversity. To meet international nature recovery targets, restoration goals must therefore move beyond consideration of native oysters as features of habitats and toward their consideration as biogenic ecosystems, several hectares in size and functionally connected. As member states of the European Union seek to develop their Nature Restoration Plans in response to the Nature Restoration Regulation (NRR), it is critical in the case of European native oyster reef ecosystems, that the recently established historical baseline is referred to, such that native oyster reefs are appropriately defined for future implementation of the NRR and the EU Habitats Directive
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