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This study aims to present a design and investigation of novel vanillin-based thiol-ene photocurable systems as candidate materials for optical three-dimensional printing.

Two vanillin acrylates, vanillin dimethacrylate and vanillin diacrylate, were tested in thiol-ene photocurable systems with 1,3-benzenedithiol. The kinetics of photocross-linking was investigated by real-time photorheometry using two photoinitiators, diphenyl (2,4,6-trimethylbenzoyl)phosphine oxide or ethyl (2,4,6-trimethylbenzoyl)phenylphosphinate in different quantities. The dependencies of rheological properties of resins on the used vanillin derivative, photoinitiator, and the presence of a solvent, as well as structure, thermal and mechanical properties of the selected polymers were investigated.

The most rigid polymers were obtained from vanillin diacrylate-based resins without any solvent. The vanillin diacrylate-based polymer possessed higher values of cross-linking density, the yield of insoluble fraction, thermal stability and better mechanical properties in comparison to the vanillin dimethacrylate-based polymer.

The kinetics of photocross-linking of vanillin-based thiol-ene systems was investigated by real-time photorheometry for the first time. The designed novel photocurable systems based on vanillin acrylates and 1,3-benzenedithiol are promising renewable photoresins for optical three-dimensional printing on demand.

The purpose of this paper is the design and investigation of novel acrylated epoxidized soybean oil-based photocurable systems as candidate materials for optical 3D printing.

Aromatic dithiols, benzene-1,3-dithiol or benzene-1,4-dithiol, were used as cross-linking agents of acrylated epoxidized soybean oil in these systems. Kinetics of photocross-linking was investigated by real-time photorheometry using two different photoinitiators, 2, 2-dimethoxy-2-phenylacetophenone or 2-hydroxy-2-methylpropiophenone, in different quantities. The effect of the initial composition on the rate of photocross-linking, mechanical, thermal properties and swelling of obtained polymers was investigated.

The rate of photocross-linking was higher, more cross-links and shorter polymer chains between cross-linking points of the network were formed when benzene-1,4-dithiol and 2, 2-dimethoxy-2-phenylacetophenone were used in compositions. The higher yield of insoluble fraction, glass transition temperatures and values of compressive modulus were obtained when benzene-1,3-dithiol and 2, 2-dimethoxy-2-phenylacetophenone were used in compositions.

This is the first study of acrylated epoxidized soybean oil-based thiol-ene system by real-time photorheometry. The designed novel photocurable systems based on acrylated epoxidized soybean oil and benzenedithiols are promising renewable photoresins for rapid optical 3D printing on demand.

Evaluates changes in the welfare system in Sweden, the UK and the USA over a decade, basing arguments on the divergence of economic globalization and domestic forces. Presents brief economic snapshots of each country, stating quite categorically that the welfare state is an impediment to capitalist profit‐making, hence all three nations have retrenched welfare systems in the hope of remaining globally economically competitive. Lays the responsibility for retrenchment firmly at the door of conservative political parties. Takes into account public opinion, national institutional structures, multiculturalism and class issues. Explores domestic structures of accumulation (DSA) and refers to changes in the international economy, particularly the Bretton Woods system (Pax Americana), and notes how the economic health of nations mirrors that of the US. Investigates the roles of multinationals and direct foreign investment in the global economy, returning to how economic policy affects the welfare state. Points out the changes made to the welfare state through privatization, decentralization and modification of public sector financing. Concludes that the main result has been an increase in earnings inequality and poverty.

Natural convection from a semi‐infinite vertical plate embedded in a fluid saturated porous medium is studied both analytically and numerically. The plate is assumed to be heated isothermally or by a constant heat flux. The porous medium, modeled according to Darcy’s law, is anisotropic in permeability with its principal axes oriented in a direction that is oblique to the gravity vector. In the large Rayleigh number limit, the governing boundary‐layer equations are solved in closed form, using a similarity transformation. Comparisons between the numerical solution of the full equations and analytical solutions are presented for a wide range of the governing parameters. The effects of the anisotropic permeability ratio K^*, of the orientation angle of the principal axes θ, and of the Rayleigh number R_H on the flow and heat transfer are investigated. Results indicate that the anisotropic properties of the porous medium considerably modify the heat transfer, velocity and temperature profiles from that expected under isotropic conditions.

This paper aims to present a three‐dimensional computational fluid dynamics (CFD) model that simulates the fluid flow, species transport and electric current flow in PEM fuel cells.

The model makes use of a general‐purpose CFD software as a basic tool incorporating fuel cell specific submodels for multi‐component species transport, electrochemical kinetics, water management and electric phase potential analysis in order to simulate various processes that occur in a PEM fuel cell.

Three dimensional results for the flow field, species transport, including waster formations, and electric current distributions are presented for two test flow configurations in the PEM fuel cell. For the two cases presented, reasonable predictions have been obtained, and this provides an insight into the effect of the flow designs to the operation of the fuel cell.

It is appreciated that the CFD modeling of fuel cells is, in general, still facing significant challenges due to the limited understanding of the complex physical and chemical processes existing within the fuel cell. The model is now under further development to improve its capabilities and undergoing further validations.

The model simulations can provide detailed information on some of the key fluid dynamics, physical and chemical/electro‐chemical processes that exist in fuel cells which are crucial for fuel cell design and optimization.

The model can be used to understand the operation of the fuel cell and provide and alternative to experimental investigations in order to improve the performance of the fuel cell.

Building on the social marketing theory, this study aims to examine the relationship between family units and obesity in Nigeria; and the social marketing interventions used to reduce and prevent obesity in the Nigerian society.

This study adopted a semi-structured interview research design with 42 obese individuals in Nigeria.

The study findings show that the family unit an individual grows up in influences their consumption behaviour, which drives their obesity. The findings reveal that obese Nigerian citizens are willing to live a healthier lifestyle due to the direct and indirect medical costs associated with obesity. Furthermore, the findings disclose the social marketing interventions – local celebrity endorsements, healthy lifestyle promotions, reduced gym membership and affordable access to healthy foods and services – used to prevent and reduce the rising obesity rates in the Nigerian society.

The findings have important theoretical implication given the focus on consumption behaviour and obesity.

The study findings provide an avenue to guide government officials, policymakers and social marketers in shaping their public policy and social marketing interventions to encourage healthier consumption and lifestyle behaviours among families and individuals in the Nigerian society.

To the best of the authors’ knowledge, this is the first research study to investigate how family units in the emerging market of sub-Saharan Africa drive obesity and the social marketing interventions used to reduce and prevent obesity. Theoretical and practical implications are discussed.

The position of universities as thought‐centres of society may not be as tenuous as some suggest, but a significant reshaping of the traditional identity and practices of universities, as we now know them, is necessary. This article examines four trends that loom ahead for universities during the next 20 years: the increasing role of private enterprise in selected areas of research, especially those that are economically viable; a stronger emphasis on business concerns – profits and financial accountability; increased demands to open new areas of academic study; and a new focus on the special interests of sub‐culture groups within academia.

This paper decomposes intra-household gender differentials in resource allocation in Nigerian agricultural households. Gender differences in agricultural households affect livelihood resources and productivity in Nigeria as in many countries.

Intersection of sex and age define gender as young male, young female, adult male and adult female within each household. Status of resource allocation was examined across the gendered groups. With the use of Oaxaca-Blinder, the mean outcome of resource allocation across the four gender groups was decomposed into components parts.

Resource allocation was generally low among farming actors, with young males, adult and young females situating below the household average. Equal endowment with adult males would have increased resources for young males, as well as young and adult females, respectively by up to 0.21, 0.07 and 0.01. The returns effects were largely significant for young and adult females.

The findings provide the premise to increase opportunities for female agricultural actors to access resources for their livelihood activities. Policies reducing the inequality between males and females in the Nigerian agricultural systems in terms of access to resources are recommended.

This study fits into the implementation of global goals to enhance gender equality and sustainable outcomes through inclusive access to productive resources in the Nigerian agrifood system.

This study operationalized gender as the intersectionality of sex and age; obtained in many African settings. This helped to capture differences in roles, opportunities and constraints within agricultural livelihoods.

The peer review history for this article is available at: https://publons.com/publon/10.1108/IJSE-04-2024-0322

The purpose of this paper is to investigate the effects of hydrogen humidity on the performance of air-breathing proton exchange membrane (PEM) fuel cells.

An efficient mathematical model for air-breathing PEM fuel cells has been built in MATLAB. The sensitivity of the fuel cell performance to the heat transfer coefficient is investigated first. The effect of hydrogen humidity is also studied. In addition, under different hydrogen humidities, the most appropriate thickness of the gas diffusion layer (GDL) is investigated.

The heat transfer coefficient dictates the performance limiting mode of the air-breathing PEM fuel cell, the modelled air-breathing fuel cell is limited by the dry-out of the membrane at high current densities. The performance of the fuel cell is mainly influenced by the hydrogen humidity. Besides, an optimal cathode GDL and relatively thinner anode GDL are favoured to achieve a good performance of the fuel cell.

The current study improves the understanding of the effect of the hydrogen humidity in air-breathing fuel cells and this new model can be used to investigate different component properties in real designs.

The hydrogen relative humidity and the GDL thickness can be controlled to improve the performance of air-breathing fuel cells.