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The study aims to determine the the optimal value of output parameters of a variable compression ratio (CR) diesel engine are investigated at different loads, CR and fuel modes of operation experimentally. The output parameters of a variable compression ratio (CR) diesel engine are investigated at different loads, CR and fuel modes of operation experimentally. The performance parameters like brake thermal efficiency (BTE) and brake specific energy consumption (BSEC), whereas CO emission, HC emission, CO₂ emission, NO_x emission, exhaust gas temperature (EGT) and opacity are the emission parameters measured during the test. Tests are conducted for 2, 6 and 10 kg of load, 16.5 and 17.5 of CR.

In this investigation, the first engine was fueled with 100% diesel and 100% Calophyllum inophyllum oil in single-fuel mode. Then Calophyllum inophyllum oil with producer gas was fed to the engine. Calophyllum inophyllum oil offers lower BTE, CO and HC emissions, opacity and higher EGT, BSEC, CO₂ emission and NO_x emissions compared to diesel fuel in both fuel modes of operation observed. The performance optimization using the Taguchi approach is carried out to determine the optimal input parameters for maximum performance and minimum emissions for the test engine. The optimized value of the input parameters is then fed into the prediction techniques, such as the artificial neural network (ANN).

From multiple response optimization, the minimum emissions of 0.58% of CO, 42% of HC, 191 ppm NO_x and maximum BTE of 21.56% for 16.5 CR, 10 kg load and dual fuel mode of operation are determined. Based on generated errors, the ANN is also ranked for precision. The proposed ANN model provides better prediction with minimum experimental data sets. The values of the R² correlation coefficient are 1, 0.95552, 0.94367 and 0.97789 for training, validation, testing and all, respectively. The said biodiesel may be used as a substitute for conventional diesel fuel.

The blend of Calophyllum inophyllum oil-producer gas is used to run the diesel engine. Performance and emission analysis has been carried out, compared, optimized and validated.

This paper aims to comprehensively analyze renewable energy alternatives in Brazil, focusing on identifying the most suitable option for investment in the country’s sustainable development.

The study adopts the step-wise weight assessment ratio analysis-multiobjective optimization by ratio analysis −3NAG (a combination of three normalization methods) methodology, a multicriteria decision-making approach, to evaluate and rank renewable energy sources based on key criteria such as resource availability, cost-effectiveness, job creation potential and environmental impact.

The analysis reveals that solar energy emerges as the preferred choice for Brazil, offering significant advantages over other alternatives such as hydroelectric, wind and biomass energy. Solar energy’s distributed generation capability, cost reduction trends and positive environmental impact contribute to its favorable position in meeting Brazil’s energy needs.

While the study provides valuable insights into renewable energy selection, there are limitations regarding the criteria’ scope and the exclusion of specific renewable energy options. Future research could explore sensitivity analyses and incorporate additional criteria to enhance the study’s comprehensiveness.

This research contributes to the existing literature by thoroughly analyzing renewable energy alternatives in Brazil using a robust multicriteria decision-making methodology. The study’s findings provide actionable guidance for policymakers, businesses and stakeholders seeking to promote sustainable energy development in the country.

The purpose of this paper is to provide an overview of the computational progress in the development of hydrogen-fired gas turbines. This review aims to identify suitable combustion models, appropriate NO_x chemistry mechanisms and NO_x emission levels for effective utilization of hydrogen as an alternative fuel in gas turbines.

Hydrogen is recognized as a potential alternative fuel for achieving exceptionally low emissions in gas turbines. The developments in conventional, trapped vortex combustor and micromix combustors are discussed, along with various computational models aimed at accurately predicting combustion and emission characteristics. The results of numerical simulations were then discussed with emphasis on their role in optimizing the combustor geometry.

Computational studies that were used to optimize the combustor geometry to reduce NO_x emissions and the flashback phenomenon are discussed. To retrofit existing gas turbines for hydrogen fuel, minor modifications that are required were discussed by analyzing extensive literature. The influence of key design and geometrical parameters on NO_x emissions and the appropriate selection of combustion models for numerical simulations in optimizing various combustion systems are elaborated.

The review emphasizes the computational studies in the progress of hydrogen-fired gas turbine developments. The previous reviews were primarily focused on the combustion technologies for hydrogen-fired gas turbines. This comprehensive review focuses on the key design parameters, flame structure, selection of combustion models, combustion efficiency improvement and impact of parametric studies on NO_x formation of various combustion systems, in particular hydrogen combustion for gas turbine applications.

A review of sustainability challenges of flame retardants (FRs) for textiles has been conducted. Specifically, the purpose of this paper is to identify and recommend solutions to sustainability challenges emanating from the raw material, processing technology and performance of the FRs used for textiles.

The approach used in preparing this paper was based on the review of various scholarly databases about the subject matter. The review approach is designed to inform the readers about the sustainability challenges of FRs for textiles. The science of burning and FRs for synthetic and cellulosic fibres were reviewed. Both synthetic and natural biodegradable FRs for textiles has been identified. The obtained literature was then synthesised to get information about sustainable challenges of non-halogenated FRs both synthetic and natural biodegradable. Finally, possible approaches for mitigating the identified challenges have been recommended.

The sustainability challenges of the FRs in terms of raw material, processing, affordability and performance have been identified. Synthetic FRs suffer from sustainability challenges in terms of raw materials, processing and non-renewability. Despite the environmental friendliness and sustainability in terms of being renewability, processability and biodegradability, natural biodegradable FRs have poor performance compared to synthetic ones. Moreover, natural biodegradable FRs depend on geographical condition and lack economic variability data. Potentially, the challenges of FRs can be mitigated through eco-friendly synthesis, chemical modification and sustainable methods of applications. Because of its renewability and environmental friendliness, biodegradable FRs have a potential to becoming sustainable if researched more.

In this review, a collection of literature about sustainability challenges of FRs and the approaches to overcome the challenges has been provided. The collected information was analysed and synthesised to bring understanding of the science of burning, types and application of FRs for textiles and biodegradable FRs. Sustainability challenges have been identified, and mitigation approaches are provided.

It is estimated that the largest share of future food fish will come from aquaculture production and that sustainable aquaculture is a precondition to realising this potential. Sustainable aquaculture will also play a key role in achieving several of the targets set out in SDG14. It is now established that most of the aquafeed ingredients used today are not sustainable and cannot support the projected growth of the sector, hence the need for sustainable alternatives. Sustainable aquaculture is multidimensional, therefore, this chapter focuses on sustainable feed ingredient sourcing. The authors explored a group of highly promising emerging novel ingredients known as microbial ingredients (MIs), means of producing them and how they can help achieve sustainable aquaculture and SDG14 targets. Specifically, the chapter narrows down on producing MIs from Norwegian spruce tree hydrolysates using a biotechnological approach and how Foods of Norway, a centre for research-based innovation at the Norwegian University of Life Sciences is leading efforts to produce feed-worthy MIs from industrial and agricultural by-products through biotechnology-based valorisation. MIs such as yeast, fungi, and bacterial meal can support the growth of Atlantic salmon without compromising the health of the fish. Thus, MI has a net positive impact on climate and can help achieve some targets in SDG14 by reducing pressure on marine resources used as fish feed ingredients. Suggestions on how to address current bottlenecks in scaling up MIs have also been provided in the chapter.

The ongoing adverse effects of climate change have led scientific think tanks to aim towards achieving net-zero greenhouse gas (GHG) emissions targets with affordable and clean energy (Sustainable Development Goal 7). One of the significant contributors to the escalating emissions rate is the use of conventional vehicles. The uptake of electric vehicles (EVs) is a promising solution for a cleaner economy. However, increased penetration poses various challenges to the power system. There is a need to explore alternatives, such as hydrogen fuel cell vehicles (HFCVs), to use the advantages of both electric and conventional vehicles and bridge the gap between them. However, the transition to hydrogen-based transport requires intensive study of its key benefits and issues, the actions that need to be taken to achieve a changeover concerning light and heavy vehicles and whether such kind of transformation is likely or even possible. This chapter highlights the brief history and mechanics of HFCVs. It further analyses the various benefits and challenges which the technology poses. Additionally, it addresses critical questions regarding the feasibility of the shift towards hydrogen fuel to satisfy the world's rapidly growing energy needs and meet net-zero targets based on real-life applications. This chapter will be a valuable resource for further research, development and education efforts in HCFVs to assist in the rapidly growing transportation needs for automobiles and other vehicles.

This paper presents a new and well-structured framework that aims to assess the current environmental impact from a Greenhouse Gas (GHG) emissions perspective. This tool includes a new set of Lean Key Performance Indicators (KPIs), which translates the well-known logic of Overall Equipment Effectiveness in the field of GHG emissions, that can progressively detect industrial losses that cause GHG emissions and support decision-making for implementing improvements.

The new metrics are presented with reference to two different perspectives: (1) to highlight the deviation of the current value of emissions from the target; (2) to adopt a diagnostic orientation not only to provide an assessment of current performance but also to search for the main causes of inefficiencies and to direct improvement implementations.

The proposed framework was applied to a major company operating in the plywood production sector. It identified emission-related losses at each stage of the production process, providing an overall performance evaluation of 53.1%. The industrial application shows how the indicators work in practice, and the framework as a whole, to assess GHG emissions related to industrial losses and to proper address improvement actions.

This paper scrutinizes a new set of Lean KPIs to assess the industrial losses causing GHG emissions and identifies some significant drawbacks. Then it proposes a new structure of losses and KPIs that not only quantify efficiency but also allow to identify viable countermeasures.

This study aims to examine how women on board influence quality and quantity disclosure of emissions discharge by the listed non-financial firms for the period of six years (2016–2021), with institutional ownership as a moderator.

The study obtained data from a sample of 83 listed non-financial firms. A content analysis technique was employed to compute emissions disclosure indexes using Global Reporting Initiatives standards from the sampled firms. Random and fixed effect regression analyses were run for both direct and moderation models. Based on the results of the Hausman tests, random results were adopted and used in examining the relationship.

The result reveals that women on board are significantly related to emission disclosure. The study also documented that institutional owners have not influenced the relationship between women directors and emissions disclosure.

The study's findings have practical implications for emerging economies, corporations and other business organizations seeking to actively involve the emissions control and reduction issues toward sustainable development goals 5, 7 and 13 in their business models and successfully communicate these efforts to stakeholders.

Listed firms in emerging economies would gain sincerity through the women directors’ knowledge, skills, demographics and ethnicity in the society. Therefore, corporate bodies in emerging economies can successfully contribute toward improving the social welfare of various segments of society by controlling current and future climate issues. Additionally, society will surely benefit when firms control the pollution discharges within the community.

This is the first study, to the best of the authors’ knowledge, that provides empirical evidence on the effect of the presence of women on board on emissions disclosure using institutional ownership as a moderator in Nigeria.

This paper aims to unravel the relationship between market-driven impacts of climate change and firms’ deployment of renewable energy (RE) innovation. The purpose is to understand how market-related forces, influenced by uncertainty, shape firms’ behaviour in response to climate change challenges.

Drawing on the behavioural theory of the firm (BTOF), the paper develops a conceptual model to decode the relationship between each category of market-driven impacts and the resulting RE innovation within firms. The model takes into account the role of uncertainty and differentiates between multinational enterprises (MNEs) and domestic firms.

The analysis reveals five key sources of market-driven impacts: investor sentiment, media coverage, competitors’ adoption of ISO 14001, customer satisfaction and shareholder activism. These forces influence the adoption of RE innovation differently across firms, depending on the level of uncertainty and the discrepancy between environmental performance and aspiration level.

This paper contributes to the literature in four ways. Firstly, it emphasises the importance of uncertainty associated with market-driven impacts, which stimulates different responses from firms. Secondly, it fills a research gap by focusing on the proactivity of firms in adopting RE innovation, rather than just operational strategies to curb emissions. Thirdly, the paper extends the BTOF by incorporating the concept of uncertainty in explaining firm behaviour. Finally, it provides insights into the green strategies of MNEs in the face of climate change, offering a comprehensive model that differentiates MNEs from domestic firms.