Search Results (95)

This study addresses the operational challenges of conventional packed cooling towers in seawater applications, where salt deposition and blockage significantly impair performance. A packing-free shower cooling tower (SCT) utilizing droplet-based heat and mass transfer is proposed as a robust alternative for high-salinity applications where conventional packed towers are prone to fouling and blockage. A comprehensive numerical model was developed and validated experimentally, showing a maximum error of less than 6% in predicting outlet water temperature. The analysis demonstrates that increasing salinity markedly reduces cooling efficiency—for instance, at threefold concentration (S ≈ 57.96 g/kg), efficiency decreased by 5.59% in summer and 4.91% in winter compared to freshwater, due to reduced vapor pressure and inhibited evaporation. However, elevating the inlet water temperature and air-to-water ratio partially counteracted these effects by enhancing evaporative and convective transfer. Larger droplet diameters also adversely affected performance, with cooling efficiency dropping from 75.87% (1 mm droplets) to 28.92% (3.5 mm droplets) in freshwater summer conditions. Notably, seasonal variations influenced the magnitude of salinity-related performance loss, with winter operations exhibiting less degradation. These findings provide critical insights and a reliable predictive tool for the design and optimization of high-salinity cooling systems. Full article

Geopolitical instability poses a significant threat to food systems by disrupting production, trade, and market access, thereby undermining both food security and long-term sustainability. Unlike peacetime food insecurity driven by poverty or climate change, conflict-related crises often involve blockades, agricultural destruction, and deliberate famine. This paper conducts a bibliometric review of the academic literature from 2010 to 2024, and partially 2025, to examine how food security and resilience under the influence of conflict have been conceptualized, focusing on their intersections with war, global food systems, and sustainability. We used the Web of Science database and tools such as VOSviewer version 1.6.18, Microsoft Excel and Bibliomagika version 2.10.0, to map thematic clusters, identify influential authors, publishers, and academic partnerships and trace the evolution of scholarly attention on this topic. Our findings reveal a growing recognition of using food as a tool of war, the increasing politicization of food aid, and heightened awareness of the fragility of agricultural systems under conflict. At the same time, significant gaps still persist, particularly in the study of “unconventional” food systems such as black markets and informal supply chains, which often sustain communities during crises but remain underexplored in mainstream scholarship. By identifying these gaps, this review outlines research priorities for developing inclusive and resilient policies, ultimately enhancing the capacity of global food systems to withstand the pressures of conflict and geopolitical instability. Full article

The biological performance and carbon dioxide (CO₂) flux of the novel and emerging concept of a membrane carbonated microalgal biofilm photobioreactor (MC-MBPBR) for wastewater treatment were investigated using mathematical modelling in conjunction with the finite-difference method. A set of differential equations was established to model the performance of an MC-MBPBR. The impacts of CO₂ partial pressure, wastewater characteristics, and biofilm thickness on the concentration profiles and fluxes of CO₂ and nutrients (N and P) to the biofilm of the MC-MBPBR were systematically studied. The modelling results showed profound impacts of these parameters on process efficiency (CO₂ transfer and N and P removals) and the existence of an optimal biofilm thickness for maximum CO₂, N, and P fluxes into the biofilm. Penetration of CO₂ through the biofilm into the bulk water phase might occur under certain conditions. An increase in gaseous CO₂ and increased influent N and P concentrations led to higher CO₂, N, and P fluxes. The optimal biofilm thickness varied with the change in wastewater characteristics and gaseous CO₂ concentration. The modelling results were in relatively good agreement with experimental results from the literature. The proposed mathematical models can be used as a powerful tool to optimize the design and operation of the novel MC-MBPBR for wastewater treatment and microalgae cultivation. Full article

Chronic respiratory diseases claim nearly four million lives annually, making them the third leading cause of death worldwide. Extracorporeal membrane oxygenation (ECMO) is often the last line of support for patients with severe lung failure. Still, its performance is limited by an incomplete understanding of gas exchange in hollow fiber membrane (HFM) oxygenators. Computational fluid dynamics (CFD) has become a robust oxygenator design and optimization tool. However, most models oversimplify O₂ and CO₂ transport by ignoring their physiological coupling, instead relying on fixed saturation curves or constant-content assumptions. For the first time, this study introduces a novel physiologically informed CFD model that integrates the Bohr and Haldane effects to capture the coupled transport of oxygen and carbon dioxide as functions of local pH, temperature, and gas partial pressures. The model is validated against in vitro experimental data from the literature and assessed against established CFD models. The proposed CFD model achieved excellent agreement with experiments across blood flow rates (100–500 $\mathrm{mL}/\min$ ), with relative errors below 5% for oxygen and 10–15% for carbon dioxide transfer. These results surpassed the accuracy of all existing CFD approaches, demonstrating that a carefully formulated single-phase model combined with physiologically informed diffusivities can outperform more complex multiphase simulations. This work provides a computationally efficient and physiologically realistic framework for oxygenator optimization, potentially accelerating device development, reducing reliance on costly in vitro testing, and enabling patient-specific simulations. Full article

Amid escalating regulatory and stakeholder pressures, corporate environmental practices emerge as strategic competitive advantages. Yet, research lacks depth on the interactions among PLU (power, legitimacy, and urgency) attributes and resource-constrained decision pathways. Integrating stakeholder theory and the attention-based view (ABV), a pressure–attention–action model is developed in this study to explain the voluntary adoption of ultra-regulatory proactive environmental practices (PEPs). An analysis of 503 Taiwanese firms using partial least squares structural equation modeling (PLS-SEM) reveals that (1) stakeholder legitimacy (β = 0.146, p < 0.01) and urgency (β = 0.215, p < 0.001) significantly increase perceived stakeholder pressure, whereas power exhibits no significant effect (β = 0.067, p > 0.05); (2) firm size positively moderates the pressure–resource linkage (β = 0.239, p < 0.001); and (3) urgency triggers partial mediation (57.4% VAF) through pressure and resources to drive proactive environmental practices. Firm size moderates pressure–resource linkages, with urgency prompting resource reallocation for environmental proactivity across scales. A dynamic PLU assessment tool and scale-sensitive strategies are proposed, challenging power-centric paradigms and aiding SMEs through collaborative networks. Limitations of the study include cross-sectional data and a regional focus, necessitating longitudinal and cross-industry validation. Full article

Background/Objectives: Elevated serum uric acid levels are associated with the occurrence, development, and adverse events of coronary heart disease (CHD) and CHD risk factors. However, the extent of any pathogenic effect of the serum uric acid on CHD and whether CHD risk factors play a confounding or mediating role are still unclear. Methods: The potential causal associations of serum uric acid with CHD were evaluated via cross-trait linkage disequilibrium score regression analysis and Mendelian randomization. The pleiotropy of genetic tools was analyzed via a Bayesian colocalization approach. Moreover, we utilized two-step MR to identify risk factors mediating the relationship between uric acid and CHD. Results: Mendelian randomization results derived from two genetic instrument selection strategies support that serum uric acid levels have a significant causal relationship with coronary artery disease, stable angina pectoris, and myocardial infarction. This causal relationship was partially mediated by diastolic blood pressure, mean arterial pressure, and serum triglycerides. Transcriptomic analysis revealed that serum uric acid may directly contribute to the development of atherosclerosis by inducing transcriptomic changes in macrophages. Conclusions: Our findings highlight that the control of serum urate concentration in the long-term management of CHD patients may be necessary. Well-designed clinical trials and foundational research are presently required to furnish conclusive proof regarding the specific clinical scenarios in which adequate reduction in urate concentrations can confer cardiovascular advantages. Full article

Typo-morphology, as interpreted by the Italian School of Planning, provides an approach to investigate the relationship between built form and socio-cultural patterns in vernacular settlements. This study examines Harran, a heritage site in southeastern Türkiye known for its distinctive conic domed dwellings, to explore how typo-morphological analysis can inform culturally sensitive design and adaptive reuse approaches. Despite its historical significance and inclusion in the UNESCO tentative list, Harran faces insufficient documentation, fragmented governance, limited conservation, and increasing pressure from urbanization and natural disasters. Using multiple sources and fieldwork, the research reconstructs the morphological evolution of Harran through diachronic maps across compound, district, and town scales. Reflections from Alberobello, Italy, i.e., the sister city of Harran and a UNESCO-listed town with a similarly unique vernacular fabric, provide a comparative view to explore different heritage management approaches. Harran evolved through informal, culture-driven growth, whereas Alberobello followed a regulated path. While Alberobello benefits from planned development and institutional preservation, Harran faces partial abandonment and neglect. By positioning typo-morphology as a conceptual planning tool, this paper emphasizes the need for context-responsive, ethically grounded, and inclusive approaches to heritage planning and conservation. It argues for planning practices that are not only technically competent but also attuned to place-based knowledge, local identities, and the long-term sustainability of living heritage. Full article

Titanium carbonitride (Ti(C,N))-based ceramics are widely utilized in mechanical machining, aerospace, and electronics, particularly in cutting tools and wear-resistant components. Two single-phase solid solution powders, non-high-entropy (Ti_0.83,W_0.07,Mo_0.04,Nb_0.03,Ta_0.04)(C_0.7,N_0.3) and high-entropy (Ti_0.6,W_0.1,Mo_0.1,Nb_0.1,Ta_0.1)(C_0.78,N_0.22), were synthesized via the carbothermal reduction–nitridation (CRN) method. Gradient-structured non-high-entropy (C-TiCN) and high-entropy (HE-TiCN) cermets were fabricated at 1450 °C by tailoring the nitrogen partial pressure in the range of 1–8 kPa. The effect of nitrogen partial pressure on the microstructure and mechanical properties of both materials was thoroughly analyzed. Both materials exhibited a three-layer gradient structure comprising a hard-phase-enriched surface layer, a binder-rich subsurface layer, and a chemically uniform core. Optimal performance was achieved at 4 kPa nitrogen partial pressure, at which both HE-TiCN and C-TiCN exhibited a desirable combination of surface hardness and fracture toughness. Compared with C-TiCN, HE-TiCN showed improvements in surface hardness and fracture toughness at subsurface and core regions (40 µm from the surface) by 4.9%, 11.2%, and 12.0%, respectively. The enhanced surface hardness of HE-TiCN is attributed to the significant lattice distortion and the synergistic effects associated with its high-entropy configuration. The improved toughness of the binder-rich layer is primarily ascribed to mechanisms such as crack deflection, crack branching, and the formation of tear ridges. These findings offer a promising strategy for developing gradient Ti(C,N)-based cermets with enhanced mechanical performance. Full article

Under the background of green development and brand building, this article aims to explore the relationship between environmental regulation on corporate brand value and the mediating effect of green innovation, which can help enterprises build a synergistic mechanism between brand building and green development, and step into a benign track of high-quality development. Based on institutional theory and resource-based theory, this paper takes the 106 listed companies on the 2018–2022 consecutive list of China’s 500 Most Valuable Brands as a sample and constructs a two-way fixed-effects model to test the impact of heterogeneous environmental regulations on green innovation and corporate brand value. The empirical results showed that: (1) Command-based environmental regulation exhibits an inverted U-shaped relationship with brand value, as it compels enterprises to adopt environmental governance in the short term but gradually erodes productive resources and triggers negative environmental and reputational effects over the long term; market-based environmental regulation demonstrates a U-shaped relationship with brand value: while it crowds out production funds and shifts costs to consumers in the short term, the government’s “resource compensation” effects ultimately outweigh “compliance cost” pressures in the long run; (2) green innovation plays a partial mediating role in the impact of command-based environmental regulation on corporate brand value; (3) the impact of environmental regulations on corporate brand value is heterogeneous in terms of the nature of corporate ownership, life cycle, and location. The above findings provide a useful reference for the government to use environmental regulation tools flexibly, optimally adjust the environmental regulatory mechanism, and promote corporate brand building and green development. Full article

High pressure and temperature (PT) experimental charges are valuable systems composed of minerals, often with quenched melt and/or fluid, synthesized to inform petrological processes deep within Earth. We explored the utility of phase mapping for the analysis of 5 GPa partial melting experiments of peridotite. We further developed an open-source software workflow to generate phase maps, which is scanning electron microscope (SEM) instrument agnostic. Phase maps were constructed offline, combining high-quality back-scattered electron images and selected element maps, and compared and verified with maps obtained with commercial automated mineralogy software. One sub-solidus assemblage, one charge containing a small percentage of melt, and a melting experiment that displayed reactions (caused by a strong thermal gradient) were analyzed. For the sub-solidus experiment, the phase map returned an accurate modal mineralogy. For the quenched melt experiments, the phase map located low-abundance phases and identified the best-suited targets for chemical analysis. Using modal mineralogy of sub-regions on maps and mutual neighboring relationships, the phase maps helped to establish equilibrium conditions and verify melting reactions inferred from mass balance. We propose phase maps as valuable tools for documenting high PT charges, particularly for layered reaction experiments. We conclude with a set of recommended instrument settings for high-quality phase maps on small experimental charges. Full article

Bistable microstructures are promising for implementation in many mictroelectromechanical system (MEMS)-based applications due to their ability to stay in several equilibrium states, high tunability and unprecedented sensitivity to external stimuli. As opposed to the extensively investigated one-dimensional curved beam-type devices of this kind, microfabrication of non-planar two-dimensional bistable structures, such as plates or shells, represents a remarkable challenge. Recently reported by us, a new moldless stamping procedure, based on pressing a soft stamp over a thin suspended metallic film, was demonstrated to be a feasible direction for the fabrication of initially curved micro plates. However, reliable implementation of this fabrication paradigm and its further development requires better understanding of the role of the process parameters, and of the effect of both the plate and the stamp material properties on the shape of the formed shell and on the postfabrication residual stresses, and therefore on the shell behavior. The need for an appropriate choice of these parameters requires the development of a systematic modeling approach to the stamping process. Here, we report on a finite element (FE)-based methodology for modeling the processing sequences of a successfully fabricated aluminum (Al) micro shell of realistic geometry. The model accounts for the elasto-plastic behavior of the plate material, the nonlinear material behavior of the foam and the contact between them. It was found that the stamping pressure and the plate material parameters are the key parameters affecting the residual shell curvature as well as its shape. Consistently with previously presented experimental results, we show that the fabrication procedure partially relieves the prestresses emerging during preceding fabrication steps, leaving a nontrivial distribution of residual stresses in the formed shell. The presented analysis approach and results provide tools for designers and manufacturers of systems including micro structural elements of shell type. Full article

Groundwater is one of the major sources of water supply for human needs. But anthropic activities such as agriculture are causing significant volume depletion and quality deterioration, favoring microbial contamination that has a negative impact on human health. The geological characteristics of the ground can influence the transport of microorganisms, especially if made of permeable rock. Furthermore, irrigation with untreated or partially treated wastewater can represent an additional health risk due to the potential transmission of pathogens to food. The aim of our research is to provide an interdisciplinary perspective on this issue by integrating hygienic, geological, and agronomic skills. Water samplings are scheduled seasonally by four monitoring campaigns in five sampling points placed in two Southern Italy regions, Apulia (one point at the outlet and two wells near the wastewater plant at Carpignano Salentino, Lecce province, Italy) and Sicily (two wells at Scicli and Pozzallo, Ragusa province, Italy) Laboratory experiments of microorganism transport in permeable rocks will be carried out under saturated and unsaturated conditions. A mathematical model of transport through porous media will be implemented and validated with laboratory measurements. The model will be used to develop a monitoring tool to control sites in Apulia and Sicily where periodic cultural and molecular detection of pathogenic bacteria, viruses, and protozoa will also be taken. In addition, an analysis of the microbiological contamination of herbaceous crops due to the use of low-quality water will be conducted to assess the Quantitative Microbial Risk Assessment (QMRA). The project will provide methodological tools to evaluate anthropogenic pressures and their impact on environmental matrices. The results will allow these pressures to be modulated to minimize environmental and agri-food microbiological contamination and protect public health. Full article

Decarbonization of industrial processes by using high-temperature heat pumps is one of the most important pillars towards sustainable energy goals. Most heat pumps are based on the standard Carnot cycle which includes an expansion valve leading to irreversible dissipation and energetic losses. Especially for high-temperature applications, these losses increase significantly, and a replacement of the conventional throttle valve with an ejector, which is an alternative expansion device, for partial recovery of some of the pressure lost during the expansion, is investigated in this paper. However, designing such a device is complicated as the flow inside is subject to multiphase and supersonic conditions. Therefore, this paper aims to streamline an approach for designing ejectors for high-temperature heat pumps using numerical simulations. To showcase the application of the design procedure, an ejector, which is used to upgrade a standard cycle high-temperature heat pump with the synthetic refrigerant R1233zdE, is developed. To design the ejector heat pump, an interaction between a fast 1D design tool, a 1D heat pump cycle simulation, and a 2D CFD simulation is proposed. An ejector is designed for a sink temperature of 130 °C, which can potentially increase the COP of the heat pump by around 20%. Preliminary measurements at off-design conditions at 100 °C sink temperature are used to validate the design procedure. The pressure distribution inside the ejector is well captured, with relative errors around 4%. However, the motive nozzle mass flow was underpredicted by around 30%. To summarize, the presented approach can be used for designing ejectors of high-temperature heat pumps, although the numerical modeling has to be further developed by validation with experiments to improve the prediction of the motive mass flow. Full article

This paper examines the feasibility of converting a Heavy-Duty (HD) Spark Ignition (SI) Compressed Natural Gas (CNG) engine to biogas fuel. A One-Dimensional (1D) simulation tool was used to model a commercially available HD SI CNG engine. The model was validated by comparing experimental and computed in-cylinder pressure, brake power, fuel, and air mass flow rates. The engine was then modified to use biogas with an injection system based on existing designs from the literature. A Spark Advance (SA) sweep was performed to assess the engine’s performance at full load. The chosen equivalence ratio was 0.85, and the engine speed was 1500 rpm. The Maximum Brake Power (MBP) and Maximum Brake Efficiency (MBE) operating points were identified. Partial load analysis was conducted starting from the MBP conditions. Results in terms of brake power, brake efficiency, and NO_x emissions are presented. Conversion to biofuel results in a reduction in power and efficiency of 33% and 4%, respectively, at 1500 rpm and full load conditions. Brake Specific NO_x emissions remained comparable. This numerical study demonstrates the feasibility of biogas conversion for HD SI engines, offering a renewable fuel alternative to reduce greenhouse gas emissions, though with trade-offs in power and efficiency. Full article

Since partial discharges, PD, are a major accelerated degradation mechanism of organic electrical insulation systems, measuring partial discharge inception voltage, PDIV, of electrical asset components in aviation and aerospace is a fundamental tool to cope with life, safety, and reliability requirements. Partial discharge phenomenology and inception voltage depend on pressure, specifically, PDIV decreases with pressure. To avoid PD inception during aircraft or aerospace vehicle operation, the value of PDIV must be known at any pressure that electrical asset components will experience. However, a lack of experimental facilities adequate to test PD on real-size asset components might prevent from having PD-related information at pressures lower (or higher) than standard atmospheric pressure, SAP. This paper presents a heuristic approach, based on physics-derived PD field inception models, that allows the estimation of PDIV at low pressure to be carried out based on measurements made at SAP, when the typology of the defect causing partial discharge is known (from SAP PD measurements), but the precise type, size, and location of the PD-generating defect is unknown. It is shown that PDIV estimates obtained by the proposed models for internal and surface discharges are in good agreement with measured values in a range from SAP to 0.05 bar, testing simple insulation geometries but also real asset components, such as motors. Full article