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Arising from the harmonic approximation in solving the vibrational Schrödinger equation, normal modes dissect molecular vibrations into distinct degrees of freedom. Normal modes are widely used as they give rise to descriptive vibrational notations and are convenient for expanding anharmonic potential energy surfaces as an alternative to higher-order Taylor series representations. Usually, normal modes are expressed in Cartesian coordinates, which bears drawbacks that can be overcome by switching to internal coordinates. Considering vibrational notations, normal modes with delocalized characters are difficult to denote, but internal coordinates offer a route to clearer notations. Based on the Hessian, normal mode decomposition schemes for a given set of internal coordinates can describe a normal mode by its contributions from internal coordinates. However, choosing a set of internal coordinates is not straightforward. While the Hessian provides unique sets of normal modes, various internal coordinate sets are possible for a given system. In the present work, we employ a normal mode decomposition scheme to choose an optimal set. Therefore, we screen reasonable sets based on topology and symmetry considerations and rely on a metric that minimizes coupling between internal coordinates. Ultimately, the Nomodeco toolkit presented here generates internal coordinate sets to find an optimal set for representing molecular vibrations. The resulting contribution tables can be used to clarify vibrational notations. We test our scheme on small to mid-sized molecules, showing how the space of definable internal coordinate sets can significantly be reduced. [ABSTRACT FROM AUTHOR]

As a widespread, abundant and zero-emission renewable energy source, solar energy has garnered significant attention as a highly feasible alternative to fossil fuels in the global energy transition. However, low overall utilization efficiency is a considerable technical obstacle to the traditional solar energy systems. In recent decades, the full-spectrum solar energy systems, where diverse solar spectral conversion methods can be synergized based on the spectral splitting technology, becomes one of the most promising solutions. Therefore, this review provides a comprehensive overview of the state-of-the-art full-spectrum solar energy systems based on spectral splitting technology. The four mainstream approaches of spectral splitting based on reflection, diffraction, refraction and absorption are introduced with the physical mechanisms and characteristics. Subsequently, tens of typical full-spectrum solar energy systems based on spectral splitting are categorized regarding energy flow topology into 4 major modes and 17 sub-modes with respective detailed analysis focused on the system integration and distinctive advantage. Next, the existing and potential applications possible for different spectral bands are summarized. Finally, conclusions and perspectives are given as the guidance for future research. • 4 mainstream approaches of spectral splitting (SS) are comparatively introduced. • Tens of full-spectrum solar energy systems based on SS are chosen as samples. • System samples are topologically categorized into 4 major modes and 17 sub-modes. • Existing and potential applications possible for different spectral bands are summarized. • Conclusions and perspectives are given as the guidance for future research. [ABSTRACT FROM AUTHOR]

Hydrogen is seen as an ideal alternative fuel to fossil fuels because it is green and sustainable. With the increasing energy crisis, developing efficient catalysts for hydrogen production to alleviate resource depletion is urgent. As a new member in the family of two-dimensional (2D) transition metal dichalcogenides (TMDs), 2D rhenium disulfide have attracted much attention based on their unique properties. In this paper, based on the unusual structural features and excellent properties of 2D rhenium disulfide, we cite their applications in the field of electrocatalytic water splitting and provide an in-depth understanding of the reaction mechanism. Furthermore, we enumerate the various synthetic methods of 2D rhenium disulfide and summarize the different strategies and current research progress in modulating their catalytic performances. Finally, we discuss the challenges faced by 2D rhenium disulfide in terms of synthetic methods and modulation strategies, and provide insights into their possible future development directions, hoping to provide valuable guidance for the design and preparation of high-performance rhenium-based electrocatalysts in the future. [Display omitted] • The unique structure and properties of 2D rhenium disulfide are presented. • Various synthetic methods of 2D rhenium disulfide are summarized. • Strategies for improving the catalytic performances are discussed. [ABSTRACT FROM AUTHOR]

This study investigates the performance, combustion, and emission characteristics of a single-cylinder compression ignition engine fueled with blends of Soy methyl ester (BS100) and macauba methyl ester (BM100) biodiesels, with hydrogen addition. Biodiesel blends (BSM10 - BSM50), and hydrogen addition (2–5%) were tested at various engine loads and speeds. The optimal blend, BSM20 (80% BS100 + 20% BM100), showed up to 7.8% higher brake thermal efficiency and 6.2% lower brake-specific fuel consumption than diesel. Emissions were significantly reduced: NOx by 12.9%, HC by 22.4%, CO by 27.5%, and smoke opacity by 18.7%. Adding 5% hydrogen to BSM20 further improved performance, reducing fuel consumption by up to 3.1% and increasing thermal efficiency by 2.5%, with substantial reductions in hydrocarbon and carbon monoxide emissions. This investigation highlights the potential of sustainable biodiesel blends and hydrogen as viable alternatives to conventional diesel fuels, offering significant environmental benefits and enhanced engine performance. • Macauba-soy biodiesel studied: Performance, emissions analyzed in diesel engines. • Optimal 80-20 blend (BSM20): Enhanced efficiency, lower exhaust temperatures. • BSM20 emissions: Decreased CO, HC, NOx, smoke compared to other blends. • Improved performance: Adding 5% hydrogen to BSM20 showed benefits. • Sustainable blend: Macauba-soy biodiesel with hydrogen is a promising fuel option. [ABSTRACT FROM AUTHOR]

Diesel engines are commonly used due to its higher reliability and better fuel conversion efficiency. However, it produces exhaust emissions like carbon dioxide (CO 2) and particulate matter (PM). Hydrogen gas is regarded as a clean fuel as it is free from carbon. The addition of hydrogen fuel enhances the burning rates and extends the flammability limits of fossil fuels, and therefore has the potential of reduced exhaust emission in diesel engines operating on dual fuel mode. This paper has investigated the effect of hydrogen addition to the performance and emissions of a single-cylinder diesel engine, working in dual fuel mode with additive di-tert butyl peroxide (DTBP). About 25% hydrogen was introduced into the cylinder on a mass basis via the engine intake manifold with the addition of additive di-tert butyl peroxide up to 5% in diesel fuel. In this experimental study, mean gas temperature, indicated mean effective pressure (IMEP), brake mean effective pressure (BMEP), polytropic index, and exhaust emissions were studied at medium (53%) and high (69%) load conditions. The indicated mean effective and brake mean effective pressure was 9.79 bar with a 3% addition of additive and 4.15 bar with the 5% addition of additive as compared with 8.71 bar and 4.11 bar diesel fuel operation. 16% hydrogen addition with 1% di-tert butyl peroxide, IMEP, and BMEP are 10.92 bar, and 4.14 bar respectively. • Additive with hydrogen fuel work as alternative fuel in diesel engine. • Effect of temperature and pressure with additive (1%–5%) and diesel fuel. • At 53% load, the reduction in polytropic index with additive from 3% to 5%. • At 69% load, enhanced in polytropic index from 1% to 5% additive. • Indicated mean effective pressure and brake mean effective pressure enhanced. [ABSTRACT FROM AUTHOR]

Technologies for producing renewable fuels and chemicals rely on the production of stable intermediates. For thermochemical technologies, pyrolysis of biomass produces oils that must compromise between carbon yield and oil quality. Bio-oil extraction has largely focused on regular bio-oils (~ 33 wt% O) and partially deoxygenated oils (< 12 wt% O). Furthermore, it is desired to extract phenolics without direct distillation of bio-oils, which would enable extraction from the heaviest portion of bio-oil. Mid-level oxygen (MLO) bio-oils (16–25 wt% O) produced from switchgrass were characterized for their ability to separate into phenolic-rich fractions. Toluene-soluble portions of the oils underwent NaOH extraction to extract one-ring phenolics, while toluene-insoluble portions were fractionated with iso-propyl alcohol (IPA). While phenolic extraction proceeded without distillation (having been a prerequisite for partially deoxygenated bio-oils), the efficiency of extraction was less than optimal, owing to the presence of other oxygenated compounds in the hydrocarbon-rich fraction. Both IPA-insoluble and IPA-soluble fractions underwent solvent liquefaction reactions with base additives. While using water as a reaction medium produced greater concentrations of phenols than when using methanol, addition of sodium carbonate produced narrower product distributions of phenols and inhibited formation of benzenediols. [ABSTRACT FROM AUTHOR]

Introduction. In the contemporary world, alternative electrical energy has become an integral part of our daily existence, with the majority of our electrical materials, electronic devices, and industrial equipment relying on this energy source. Consequently, ensuring the quality of the electrical signal obtained is of paramount importance in the process of converting and distributing electrical energy. The improvement of the output voltage inverter can be achieved through adjustments to the inverter structure or by refining the control strategy. The novelty of the presented research lies in an innovative approach that employs real-time modulation for efficient control over the reduction of harmonics, alongside managing the fundamental component. This approach is applicable to both bipolar and unipolar configurations, featuring quarter-wave and half-wave symmetries. Purpose. Employing this modulation strategy aims to enhance the durability of the switching components and enhance the voltage output of the inverter. Methods. The methodology is founded on a sine-sine modulation as its foundational model. It constitutes an inventive pulse width modulation technique in which a reference sinusoidal waveform, operating at the desired signal frequency, is compared to a modified carrier signal with an identical time period as the reference signal. Results. This paper introduces a broader and more comprehensive approach, alongside specific solutions, for the control and mitigation of harmonics in three phase voltage source inverters. The proposed method offers precise control over the reduction of harmonics and the fundamental component, and it can be implemented in extensive power electronic converters. Practical value. To assess the effectiveness of the given control approach, we conducted simulations as well as real-time implementation employing Dspace DS1104 controller board. The outcomes were highly favorable, confirming the effectiveness and validity of the suggested control algorithm. References 15, tables 4, figures 7. [ABSTRACT FROM AUTHOR]

The protonic ceramic fuel cells (PCFCs) can convert the chemical energy of fuel directly into electric power, with the advantages of high efficiency and alternative fuel range at intermediate temperatures. Ammonia has been regarded as a promising fuel for PCFCs due to its carbon‐free and hydrogen‐rich properties, high volumetric energy density and easy storage/transportation. However, the performance of ammonia PCFCs (NH3‐PCFCs) is far inferior to the hydrogen PCFCs (H2‐PCFCs) because of the sluggish and complex kinetics at anodes. In this study, we established an elementary reaction kinetic model for NH3‐PCFCs, investigated the effect of reaction parameters, anode components and reaction partition, and explored the coupling mechanism between the ammonia decomposition and electrochemical reaction. Importantly, the ammonia decomposition and electrochemical reaction can be flexibly regulated by adjusting anode parameters, then affecting the performance ratio of NH3‐PCFCs and H2‐PCFCs. The detailed rate‐determining steps were further identified by experimental and model analysis. Thus, the ammonia/hydrogen performance ratio of the cell can exceed 95% at 550°C after accelerating the ammonia decomposition reaction. Our work provides insights into the kinetics in NH3‐PCFCs for improving their performance with optimization. [ABSTRACT FROM AUTHOR]

Ammonia is gaining increasing attention as a green alternative fuel for achieving large-scale carbon emission reduction. Despite its potential technical prospects, the harsh ignition conditions and slow flame propagation speed of ammonia pose significant challenges to its application in engines. Non-equilibrium plasma has been identified as a promising method, but current research on plasma-enhanced ammonia combustion is limited and primarily focuses on ignition characteristics revealed by kinetic models. In this study, low-temperature and low-pressure chemistry in plasma-assisted ammonia oxidative pyrolysis is investigated by integrated studies of steady-state GC measurements and mathematical simulation. The detailed kinetic mechanism of NH3 decomposition in plasma-driven Ar/NH3 and Ar/NH3/O2 mixtures has been developed. The numerical model has good agreements with the experimental measurements in NH3/O2 consumption and N2/H2 generation, which demonstrates the rationality of modelling. Based on the modelling results, species density profiles, path flux and sensitivity analysis for the key plasmaproduced species such as NH2, NH, H2, OH, H, O, O(1D), O2(a1Dg), O2(b1Sgþ), Ar*, H, Arþ, NH3þ, O2 in the discharge and afterglow are analyzed in detail to illustrate the effectiveness of the active species on NH3 excitation and decomposition at low temperature and relatively higher E/N values. The results revealed that NH2, NH, H as well as H2 are primarily generated through the electron collision reactions e þ NH3 /e þ NH2 þ H, e þ NH3/e þ NH þ H2 and the excited-argon collision reaction Ar* þ NH3 þ H/Ar þ NH2 þ 2H, which will then react with highly reactive oxidative species such as O2*, O*, O, OH, and O2 to produce stable products of NOx and H2O. NH3 / NH is found a specific pathway for NH3 consumption with plasma assistance, which further highlights the enhanced kinetic effects. [ABSTRACT FROM AUTHOR]

The burning and utilization of fossil fuels contribute to climate change and emit pollutants that raise the risk of asthma, heart diseases, respiratory diseases, and strokes in humans. There is an unprecedented rise in the use of petroleum fuel, consequently, increasing the concern over fossil fuel utilization. To overcome this burning problem, there is an urgent need to switch to biofuels, which are an attractive alternative to petroleum fuel. Biofuels are renewable, nontoxic, sulfur-free, cost-effective energy sources that can be derived from the fatty acids found in plant oils via transesterification, esterification, and catalytic cracking techniques. This review focuses on the feedstocks as well as their fatty acid composition used to produce the first two out of the four generations of biofuel and reports up-to-date information on the differing reaction conditions involved in these processes. Various types of feedstocks, reactors, catalysts, and production techniques are used to produce biofuels which are discussed in this article. An emphasis has been put on the fatty acids of edible and non-edible oils and their usage to produce biodiesel with a discussion of the in-depth knowledge of properties as well as the applications of biofuels in detail. [ABSTRACT FROM AUTHOR]

In this paper, a Multi-Criteria Decision Analysis methodological framework is developed to rank alternative fuel buses. It is applied to the case-study of the public transportation system of the island of Gotland in Sweden. Seven alternative fuel buses are identified: bioethanol, biodiesel, biogas, plug-in hybrid electric biodiesel, plug-in hybrid electric biogas, battery electric and hybrid electric hydrogen fuel cell buses. These alternatives are evaluated under 11 criteria that are categorized under four dimensions and measured under a Life Cycle Sustainability Analysis approach where possible. The ranking is accomplished by means of the weighted summation method; weights are determined through the Analytic Hierarchy Process. Explicit weights on these criteria provided by local experts and stakeholders are used to evaluate the alternatives under various island-specific scenarios. Results show that biogas and plug-in hybrid electric biogas buses are the preferred alternatives as long as biogas is produced from waste residuals; otherwise, the import of biodiesel could be the preferred short-term alternative. Bioethanol appears to be the least suitable fuel. The developed methodological framework proved helpful to the local authorities of Gotland when they sought to identify the best compromise fuel bus solution and has shown that it can be applied in similar case-studies. [ABSTRACT FROM AUTHOR]

To limit the negative impact on the environment, increasingly stringent regulations are being introduced regarding the reduction of pollutant emissions. In automotive applications, reciprocating internal combustion engines (ICE) are under immense pressure due to emissions. Society aims to move away from fossil fuels. However, it is acknowledged that ICE will continue to play a significant role in electricity generation systems and certain transportation sectors. To achieve zero emissions or drastically reduce emissions, alternative carbon-free fuels are being pursued. Hydrogen (H 2) is a natural substitute for fossil fuels, and recently, ammonia (NH 3) has been considered an intriguing fuel. Ammonia is easier to transport and store compared to hydrogen. NH 3 is a good hydrogen carrier with significant potential for use in ICE. However, ammonia combustion in such applications exhibits challenges related to its low burning rate. Here, hydrogen emerges as a high reactivity fuel, used as a combustion enhancer for NH 3. Hydrogen-assisted ammonia combustion shows great promise for future of ICE. This paper presents a summary of research findings on the NH 3 /H 2 combustion process in a spark-ignition ICE. Concepts of dual-fuel NH 3 /H 2 engine operation, the influence of fuel proportions on cylinder pressure profiles, heat release, combustion stages, and engine emissions aspects are discussed. The directions of development of SI piston engines powered by NH 3 /H 2 are given. • Assessment of NH 3 and NH 3 /H 2 combustion strategies in the SI engine • Direct injection of ammonia reduces its content in exhaust gases. • SI engine powered by NH 3 requires high ignition energy. • The challenge is to reduce N 2 O emissions. • Hydrogen expands the spectrum of application of NH 3 as a fuel for the SI engine. [ABSTRACT FROM AUTHOR]

Anaerobic digestion of abundant feedstock from biomaterials is a good innovative fossil fuel alternative approach for the synthesis of green fuel (biogas). Rotatable central composite design (CCD) and machine learning (ML) via Python coding were successfully used to design, optimize, and predict the rate of biogas production from stew‐rice and eggs digestate with Udara seeds in an anaerobic unit. Two‐input parameters, such as inoculation ratio (S/I) and hydraulic reaction time (HRT) were considered, resulting in 13 experimental setups under mesophilic surroundings of 25–34°C. Mixture ratios of substrate/inoculum (S/I) of 0.98:1, 1.5:1, 2.75:1, 2.75:1, 4:1, 1.5: 1, and 4.52:1 were used against 30, 20, 44.14, 15.86, 40, 40, and 30 days HRT as modeled by CCD rotatable to optimize biogas production from crushed Udara seeds with spoilt stew‐rice and eggs digestate. From the results, it was observed that the coefficient of determination (R2) of 0.9573 was generated via CCD rotatable whereas, the R2 of 1 was generated from the multivariate regression of ML approach. Also, the data and graphs derived via ML were superior to the ones derived from CCD rotatable. However, the maximum output of 4.84 L at 4 mixing ratio and 40 days HRT from CCD rotatable is close to the ML value of 4.89 L under the same input factors, yet ML yielded more. Thus, it is clear that the Python‐based ML algorithm approach has the potential to predict biogas output better than CCD rotatable. However, the Gas Chromatography Mass Spectrometry analysis of the highest output produced generated 63.29% biomethane and 26.71% CO2 by volume and produced a flashpoint of −167°C which is flammable. Thus, the generated biogas via an anaerobic unit can be transmitted into large‐scale commercial applications for the betterment of mankind. [ABSTRACT FROM AUTHOR]

Aqueous zinc metal batteries are emerging as a promising alternative for energy storage due to their high safety and low cost. However, their development is hindered by the formation of Zn dendrites and side reactions. Herein, a macromolecular crowding electrolyte (MCE40) is prepared by incorporating polyvinylpyrrolidone (PVP) into the aqueous solutions, exhibiting an enlarged electrochemical stability window and anti‐freezing properties. Notably, through electrochemical measurements and characterizations, it is discovered that the mass transfer limitation near the electrode surface within the MCE40 electrolyte inhibits the (002) facets. This leads to the crystallographic reorientation of Zn deposition to expose the (100) and (101) textures, which undergo a "nucleation‐merge‐growth" process to form a uniform and compact Zn deposition. Consequently, the MCE40 enables highly reversible and stable Zn plating/stripping in Zn/Cu half cells over 600 cycles and in Zn/Zn symmetric cells for over 3000 hours at 1.0 mA cm−2. Furthermore, Na0.33V2O5/Zn and α‐MnO2/Zn full cells display promising capacity and sustained stability over 500 cycles at room and sub‐zero temperatures. This study highlights a novel electrochemical mechanism for achieving preferential Zn deposition, introducing a unique strategy for fabricating dendrite‐free zinc metal batteries. [ABSTRACT FROM AUTHOR]

H2 produced via water electrolysis is a promising alternative to traditional energy, with electrodes playing a dominant role in the production process. To date, numerous studies have screened different types of biomass as precursors to synthesize electrocatalysts with practical functions, but the clear conclusions in this field are unfortunately absent. Therefore, herein, the recent advances in biomass-derived electrocatalysts for HER/OER processes are summarized, focusing on the design of carbonaceous structures from multiple components, the incorporation of supports with single or several metals and the available methods for their modification via defect engineering. Subsequently, the overall efficiency of electrochemical water splitting on a biomass-derived electrolyzer is discussed in depth together with the upgraded strategy for the so-called electrosynthesis of chemicals paired with H2 production. Finally, the technical bottlenecks that need to be properly resolved in the near future for the development of these electrocatalysts originating from biomass are presented. It can be expected that this review will not only contribute to the in-depth knowledge on the rational synthesis of biomass-derived materials as electrodes, but also present new opportunities for the valorization of biomass resources in electrochemical applications. [ABSTRACT FROM AUTHOR]

As demand for clean energy continues to increase, scientists are exploring alternative sources to fossil fuels, which are a major contributor to climate change. Hydrogen (H 2) has been identified as a promising solution due to its ability to be derived from water-splitting using electricity, solar, or thermal energies. Solar water-splitting is a conventional and eco-friendly approach for producing green H 2 with high energy storage capacity among various power sources. Perovskite (PSK) minerals have emerged as a popular choice for H 2 production due to their unique optoelectronic properties, including high carrier mobility, tunable bandgap, and strong light absorption. These properties make PSK materials suitable for perovskite-based H 2 generation processes, including photocatalytic, electrocatalytic, photo-electrocatalytic, and thermochemical processes for hydrogen generation. This investigation comprehensively overviews recent breakthroughs, challenges, and perspectives in PSK-based hydrogen generation systems. We discuss the reasons behind the selection of PSK materials, including their high efficiency, stability, and low cost, as well as opportunities to enhance their performance through material optimization and device engineering. Overall, PSK-based H 2 Evolution systems hold significant promise for addressing the pressing energy and environmental challenges of our time. [Display omitted] • Perovskite materials offer high efficiency & stability, driving green H 2 production. • Solar water-splitting with PSKs enables eco-friendly H 2 generation. • Tunable bandgap & strong light absorption make PSKs ideal for H 2 systems. • Material optimization & device engineering enhance perovskite-based H 2 evolution. [ABSTRACT FROM AUTHOR]

This review comprehensively evaluates the integration of solar-powered electrolytic hydrogen (H 2) production and captured carbon dioxide (CO 2) management for clean fuel production, considering all potential steps from H 2 production methods to CO 2 capture and separation processes. It is expected that the near future will cover CO 2 -capturing technologies integrated with solar-based H 2 production at a commercially viable level, and over 5 billion tons of CO 2 are expected to be utilized potentially for clean fuel production worldwide in 2050 to achieve carbon-neutral levels. The H 2 production out of hydrocarbon-based processes using fossil fuels emits greenhouse gas emissions of 17-38 kg CO 2 /kg H 2. On the other hand,. renewable energy based green hydrogen production emits less than 2 kg CO 2 /kg H 2 which makes it really clean and appealing for implementation. In addition, capturing CO2 and using for synthesizing alternative fuels with green hydrogen will help generate clean fuels for smart cities. In this regard, the most sustainable and promising CO 2 capturing method is post-combustion with an adsorption-separation-desorption processes using monoethanolamine adsorbent with high CO 2 removal efficiencies from flue gases. Consequently, this review article provides perspectives on the potential of integrating CO 2 -capturing technologies and renewable energy-based H 2 production systems for clean production to create sustainable cities and communities. [Display omitted] • Carbon capture-storage and H 2 production technologies are comprehensively reviewed. • Clean fuel production technologies from captured CO 2 and produced H 2 are evaluated. • Renewable-powered integrated systems for clean fuel production are proposed. • Solar-powered H 2 production from water is a promising solution in integrated systems. • Promising carbon management and green energy support sustainable cities and communities. [ABSTRACT FROM AUTHOR]

The present study aims to the feasibility and potential application of briquettes obtained from dehydrated mahogany sawdust as a feasible and eco-friendly alternative to traditional fuels. Briquettes have been observed to be widely utilized in rural areas for culinary purposes. These briquettes are derived from various biomass sources, which contribute to the reduction of carbon emissions and the promotion of ecological consciousness in waste management and energy generation. Lantawan Municipality of Basilan, renowned for its agricultural resources, such mahogany lumber and sawdust as substantial agricultural wastes that can be potential to the production of biofuel. Notably, CMS exhibits favorable characteristics for briquette manufacturing, owing to its capacity for carbon sequestration, durability, efficiency, burning time, kindling time, and heat quality. This study aims to assess the physical characteristics, efficacy, and combustion time of CMS charcoal briquettes by means of a Likert questionnaire. Results revealed a cumulative average rating of 5.0 (Very Much liked) in all parameters expressing high praise for the briquettes' remarkable capacity. Although CMS briquettes performed well in all physical tests, proving their viability as an eco-friendly energy source, recommendation such as collection and transformation of mahogany sawdust into sustainable alternative biomass fuel, Enhancement of the efficiency and accessibility by involving Technical-Vocational-Livelihood (TVL) students in the design and creation of machines that could optimize the production process and testing briquettes to various parameters such as fixed carbon content, moisture content, and ash content to improve product yields and performances. [ABSTRACT FROM AUTHOR]

During the British Civil Wars, London suffered a severe energy shortage. By the mid-seventeenth century, the English capital was highly dependent on supplies of coal from the North-East of England. However, during the civil wars, the predominantly Parliamentarian city’s access to coal was restricted when the Royalists secured control of Newcastle and its coal reserves. The constriction of the coal supply of London caused an energy crisis in the capital, forcing the Parliamentarians to introduce price controls and seek alternative supplies of fuel. This article argues that ‘weaponisation of energy’ and ‘energy policy’ are appropriate terms to describe London’s coal supply in this period, given the clear parallels with modern energy policies and conflict. This article will further argue that the use of this term makes historians engage with the importance of energy even in premodern conflicts, and acknowledge that contemporaries were aware of its paramount strategic importance. [ABSTRACT FROM AUTHOR]

The two significant challenges facing the world are growing pollution issues and fossil fuel depletion. Emissions emanating and consumption of fossil fuels in diesel engines are reduced by modifying engine operating parameters and by developing more efficient alternative fuels. In view of this, the current work evaluates the effect of ZnO nanoparticles mixed with diesel-ethanol blend on the working characteristics of diesel engine at different CR's and loads. The test fuels selected for the experimental work are pure diesel, DE10, DE10ZnO50 and DE10ZnO100, and the compression ratios are 16.5, 17.5 and 18.5. Using ultrasonic agitation, ZnO nanoparticles were incorporated in fuel blends in the presence of 2% surfactant span80. All fuel blends were tested for their physicochemical properties, and it was noted that the fuel properties improved when ZnO nanoparticles were added to the test blends. The results showed that at CR 18.5, the DE10ZnO100 fuel blend shown maximum improvement in engine working characteristics as compared to other blends. In comparison to diesel at CR 18.5 for DE10ZnO100 blend, BTE enhanced by 5.73% and BSFC was reduced by 8.31%. CO, NOx and UHC emissions are reduced by 21.96%, 6.41% and 12.07%, whereas CO2 emissions have increased by 7.44%, respectively. Different concentration of ZnO nanoparticles incorporated diesel-ethanol blend is prepared. The effect of ZnO nanoparticles diesel-ethanol blend at various compression ratios of diesel engine was investigated Optimal results are noted for the DE10ZnO100 blend at compression ratio 18.5. Improvements in BTE and BSFC is 5.73% and 8.31% as compared to diesel at CR 18.5 for DE10ZnO100 blend. CO, UHC and NOx reduced by 21.96%, 12.07% and 6.41%. [ABSTRACT FROM AUTHOR]

Sustainable alternatives for the energy intensive synthesis of H2O2 are necessary. Molecular cobalt catalysts show potential but are typically restricted by undesired bimolecular pathways leading to the breakdown of both H2O2 and the catalyst. The confinement of cobalt porphyrins in the PCN‐224 metal‐organic framework leads to an enhanced selectivity towards H2O2 and stability of the catalyst. Consequently, oxygen can now be selectively reduced to hydrogen peroxide with a stable conversion for at least 5 h, illustrating the potential of catalysts confined in MOFs to increase the selectivity and stability of electrocatalytic conversions. [ABSTRACT FROM AUTHOR]

The hydrodeoxygenation (HDO) reaction provides a promising catalytic strategy to remove oxygen in biomass‐derived bio‐oil to produce renewable transportation fuels and value‐added chemicals. The development of highly efficient and stable HDO catalysts plays an essential role in biomass valorization. Metal‐zeolite bifunctional catalysts have been well‐developed as the effective HDO catalysts in upgrading lignin‐derived phenolics due to their excellent activity, selectivity, and thermal and hydrothermal stability. However, clarifying the roles of the active sites and their synergistic effect, and establishing effective structure‐performance relationships in the HDO process still face challenges. In this review, we first survey the conventional catalysts applied in the HDO of bio‐oil, followed by thoroughly discussing the roles of metal centers, acid sites, supports, and their impacts on the HDO process of phenolic model compounds or bio‐oil. Finally, a discussion on the stability and deactivation of metal‐zeolite catalysts, especially in the aqueous‐phase HDO reaction, is provided. This critical review offers new insights into the development of state‐of‐the‐art metal‐zeolite bifunctional catalysts with well‐defined porosity and metal‐acid properties for viable biomass valorization. [ABSTRACT FROM AUTHOR]

Renewable energy sources have been recognized as a viable alternative to fossil fuels. Among them, lignocellulosic biomass has emerged as a promising option for producing valuable bio-products, especially employing residual or waste material due to its consistency, reliability, local availability, and carbon neutrality. However, its efficient utilization is limited by the recalcitrance of cell walls, mainly caused by two chemical compounds, hemicellulose and lignin, reducing the accessibility to cellulose. Consequently, the hemicellulose and/or lignin in the cell wall need to be removed or rearranged to increase the accessibility to cellulose through the pretreatment of lignocellulosic biomass. Among the different pretreatments, oxidative processes efficiently enhance the digestibility of cellulose in lignocellulosic biomass, breaking down the complex structure of lignocellulosic biomass and making it more accessible for subsequent enzymatic or microbial degradation. Moreover, oxidative processes improve the reaction kinetics, are versatile in treating a wide range of lignocellulosic feedstocks, and reduce the generation of waste products. Therefore, this review aims to provide a detailed overview of the properties and composition of lignocellulosic biomass, its potential, and a comprehensive analysis of oxidative pretreatments, their advancements and recently developed innovative technologies. Furthermore, the application and economic feasibility of utilizing lignocellulosic biomass and the key obstacles hindering its widespread adoption are highlighted in this review. [ABSTRACT FROM AUTHOR]

AbstractAquaculture has proven to be a vital and very efficient source of animal protein to meet the food demands of the ongoing increase in the global human population. In response to the rising accumulation of atmospheric greenhouse gases (GHG), principally of anthropomorphic origin from use of fossil fuel energy sources, global oceanic and atmospheric temperatures have risen to cataclysmic levels that have produced dramatic changes in climate. Aquaculture, like all animal production systems is a contributor to global GHG, and strategies must be introduced to mitigate current and future threats of climatic disruptions. Important pathways to reduce carbon footprint contributions include increases in efficiency of production and appropriate choice of ingredients for manufacture of sustainable aquafeed. For fed production systems, use of feed grade rather than food grade sources of ingredients must typically predominate. Additionally, use of waste consistent with circular bioeconomy concepts and the guidance provided through results of life cycle assessment (LCA) must be applied to aquafeed production. An integral connection of these efforts with a timely transformation from use of fossil fuel to renewable sources of energy is essential. Achieving sufficient reductions in both aquaculture’s carbon footprint and fossil fuel use within the next 25 years should determine whether the projected contribution of aquaculture to global food security is realized. [ABSTRACT FROM AUTHOR]

Among the different hydrogen premixed combustion concepts, direct injection (DI) is one of the most promising for internal combustion engine (ICE) applications. However, to fully exploit the benefits of this solution, the optimization of the mixture preparation process is a crucial factor. In the present work, a study of the hydrogen-air mixture formation process in a DI H 2 -ICE for off-road applications was performed through 3D-CFD simulations. First, a sensitivity analysis on the injection timing was carried out to select the optimal injection operating window, capable of maximizing mixture homogeneity, without a significant volumetric efficiency reduction. Then, different spray injector guiding caps were tested to assess their effect on in-cylinder dynamics and mixture characteristics consequently. Finally, the impact of swirl intensity on hydrogen distribution has been assessed. The optimization of the combustion chamber geometry has allowed the achievement of significant improvements in terms of mixture homogeneity. • Diesel engines have high retrofit potential in H2 conversion. • Early injection timings increase uniformity, H2 backflow has to be avoided. • Injector cap properly guide hydrogen jet; not sufficient as a stand-alone solution. • Intense swirl severely reduces mixture homogeneity into the cylinder. • Combination of spray cap and swirl chamfers design improves homogeneity. [ABSTRACT FROM AUTHOR]

Diesel generators are widely used to produce electricity and heat in remote communities. However, their use contributes to harmful pollutant and greenhouse gas (GHG) emissions, negatively impacting the environment and public health. Syngas, which is a sustainable fuel, can play an important role in the transition from petroleum to renewable fuels. When used in dual-fuel diesel engines, it can contribute to reducing GHG emissions and the cost of transporting diesel, especially for rural and remote communities. This study investigates the effects of optimizing the diesel direct injection (DI) and exhaust gas recirculation (EGR) strategies on the combustion and emission performance of a syngas-diesel dual-fuel generator at constant load. The experiments were conducted using a 30-kW generator with a four-stroke, four-cylinder, turbocharged, and electronically controlled direct-injection diesel engine. The intake manifold of the engine was modified to allow introducing syngas upstream of the turbocharger. The syngas was simulated using individually controlled flow rates of hydrogen (H 2), carbon monoxide (CO), carbon dioxide (CO 2), and nitrogen (N 2). The syngas flow rate was adjusted to replace 40% of the energy provided by diesel fuel while optimizing the diesel DI parameters such as the pilot injection timing, main injection timing and diesel direct injection rail pressure, as well as the EGR rate. The findings of this study reveal that optimizing diesel injection strategy and appropriately raising the EGR rate have a positive impact on the engine performance and emissions. • Optimizing diesel injection strategies and EGR rate of a syngas-diesel dual-fuel diesel engine. • Hydrogen-rich syngas enhances combustion efficiency and emissions control. • Fine-tuning of pilot injection timing and duration improved the engine efficiency and emissions. • Increasing EGR rate stabilized emissions, with notable reductions in NOx and CO levels. • Adjustment of the main injection timing positively impacted combustion characteristics. • Increasing the injection pressure resulted in notable reductions in CO and PM emissions. [ABSTRACT FROM AUTHOR]

The paper aims to investigate the fuel and system options for a floating power plant (FPP) considering economic performance and the decarbonization goals of the International Maritime Organization. Various case studies have been assessed using a reference FPP, encompassing the instant and future retrofitting scenarios. The ready-to-use scenarios involve alternative fuel and organic Rankine cycle-based waste heat recovery system usage. Nuclear energy systems have been evaluated within the reference FPP since they are suitable candidates for achieving zero-carbon objectives and providing low-cost electricity. A simulation framework created in Python has calculated the fuel consumption regarding the power requirement and organized the approaches used in the study. An environmental model comparing the systems has been built to calculate upstream and operational emissions. The cost projection model for 2030 and 2050 has assessed the economic performance. Technique for Order of Preference by Similarity (TOPSIS) one of the multi-criteria decision-making approaches has ranked the systems considering the outcomes of economic and environmental models over the years. Findings demonstrate that the current fuel usage scenario of the FPP is not suitable both environmentally and economically. The other emissions can be near zero and greenhouse gases can be decreased by up to 15.95% using alternative fuels. Nuclear energy is a strong candidate to meet the 2050 targets, but its viability is largely based on economic performance. [ABSTRACT FROM AUTHOR]

Depleting global petroleum reserves and skyrocketing prices coupled with succinct supply have been a grave concern, which needs alternative sources to conventional fuels. Oleaginous microalgae have been explored for enhanced lipid production, leading towards biodiesel production. These microalgae have short life cycles, require less labor, and space, and are easy to scale up. Triacylglycerol, the primary source of lipids needed to produce biodiesel, is accumulated by most microalgae. The article focuses on different types of oleaginous microalgae, which can be used as a feedstock to produce biodiesel. Lipid biosynthesis in microalgae occurs through fatty acid synthesis and TAG synthesis approaches. In-depth discussions are held regarding other efficient methods for enhancing fatty acid and TAG synthesis, regulating TAG biosynthesis bypass methods, blocking competing pathways, multigene approach, and genome editing. The most potential targets for gene transformation are hypothesized to be a malic enzyme and diacylglycerol acyltransferase while lowering phosphoenolpyruvate carboxylase activity is reported to be advantageous for lipid synthesis. [ABSTRACT FROM AUTHOR]

Approximately 25% of global carbon emissions come from food production. Renewable fuels are crucial for curbing greenhouse gas (GHG) emissions from vehicles, non-road machines, and agricultural machinery. Tractors, key to modern farming, are central to these efforts. As agriculture strives for sustainability, alternative fuels like methanol and hydrotreated vegetable oil (HVO) are arousing interest because they are renewable and offer potential for blending for use in diesel engines. Methanol and HVO have limited solubility in direct mixing, so the addition of a co-solvent is essential. This study addresses the research gap regarding the properties of HVO and methanol blends with co-solvents. It investigated the impact of three co-solvents, 1-dodecanol, 1-octanol, and methyl butyrate, on the miscibility of HVO and methanol. The experimental measurements cross-varied the co-solvent type with different blending ratios (MeOH5 and MeOH10). Investigated parameters include fuel density, kinematic viscosity, distillation properties, and surface tension. The co-solvents enabled the formation of a singular, clear, and homogeneous phase in methanol-HVO blends. The co-solvent 1-dodecanol demonstrated the highest solubilizing capacity for MeOH5 and MeOH10 blends, followed by 1-octanol. Adding co-solvents led to increased fuel density, decreased kinematic viscosity, and small changes in surface tension. These findings contribute to the optimization of methanol–HVO fuel blends for efficient and environmentally friendly use in vehicles, non-road machinery, and agricultural machinery. [ABSTRACT FROM AUTHOR]

The automotive industry is experiencing radical changes under the pressure of institutions that are increasingly reducing the limits on CO2 and pollutant emissions from road vehicles powered by internal combustion engines (ICEs). A way to decarbonize the transport sector without disrupting current automotive production is the adoption of alternative fuels for internal combustion engines (ICEs). Hydrogen is very attractive, thanks to the zero-carbon content and very high laminar flame speed, allowing for extending the lean burn limit. Other alternative fuels are methanol and ethanol. This work deals with the conversion of a small-sized passenger car powered by a three-cylinder spark ignition (SI) engine for the use of alternative fuels. In particular, the spark timing has been optimized to improve the fuel economy under every operating condition. The optimization procedure is based on the MATLAB/Simulink® R2024a-GT-Power co-simulation analysis and minimizes the fuel consumption by varying the spark timing independently for each cylinder. In particular, at full load, the algorithm reduces the spark timing only for the cylinder in which knock is detected, reducing fuel consumption by about 2% compared to the base calibration. This approach will be adopted in future activities to understand how the use of alternative fuels affects the ignition control strategy. [ABSTRACT FROM AUTHOR]

Currently, a power-to-gas technology that obtains electrolytic hydrogen from renewable energy sources, synthesizes it with carbon dioxide, and converts it to methane has received a great deal of attention. It is called methanation, but there are few studies examining alternative substances to replace the raw material of hydrogen. Since hydrogen does not exist naturally, it is important to find other substances that react with carbon dioxide. We focus on flammable gases formed in oil refineries and petrochemical plants. In this study, based on chemical equilibrium calculations of the so-called NASA-CEA, we tested several gases including flammable and nonflammable gases by reacting them with carbon dioxide. Some of them are included in flare stacks. The reactants in the present gas conversion were H2O, CH3OH, C2H5OH, NH3, CH3CN, CH3N2CH3, C3H8O (1-propanol), C3H8O (2-propanol), C2H6, C2H4, C3H8, C3H6, C3H4 (allene), C3H4 (propine), C6H5OH, (CH3COOH)2, HCOOH, HF, HCl, HBr, H2S, HNO3, and SiH4. The results show that substances with more hydrogen atoms per mol of reactant, such as C3H8, CH3N2CH3, and SiH4, can produce more synthetic methane. One more finding is that graphite due to coking increases proportionately to the number of carbon atoms in the chemical formula. [ABSTRACT FROM AUTHOR]

The use of biofuels represents a promising means of achieving a sustainable future and offers considerable economic and environmental benefits. Since they are derived from organic sources, such as vegetable oils and animal fats, biofuels can mitigate the effects of greenhouse gas emissions, improve air quality, support local agriculture, create employment opportunities, and enhance energy security by reducing dependence on fossil fuels. However, introducing these alternative fuels to the aviation sector remains a significant challenge. Thus, it is vital to investigate the potential of sustainable aviation fuel (SAF) and discover how to overcome the technological obstacles to its integration into mainstream aviation to attain broader decarbonization objectives. This article seeks to contribute to a discussion about SAF by examining how it has evolved and its connections to related patents. This article is a comprehensive study of biofuel innovation, highlighting the complex relationships between academia, industry, and other stakeholders. It is hoped that the findings from this study will provide a clearer understanding of the catalysts involved in SAF innovation and provide valuable insights for policymakers, academics, and professionals in the field who are committed to shaping the trajectory of sustainable energy technologies in the future. [ABSTRACT FROM AUTHOR]

Biogas presents a renewable fuel source with substantial potential for reducing carbon emissions in the energy sector. Exploring this potential in the farming sector is crucial for fostering the development of small-scale distributed biogas facilities, leveraging indigenous resources while enhancing energy efficiency. The establishment of distributed biogas plants bolsters the proportion of renewable energy in the energy matrix, necessitating efficient power generation technologies. Given their proximity to bio-waste production sites like farms and digesters, optimising combined heat and power generation systems is imperative for energy self-sufficiency. Small-scale biogas facilities demand specific power generation technologies capable of achieving notable efficiencies, ranging from 40% to 55%. This study focuses on employing Solid Oxide Fuel Cells (SOFCs) in biogas-to-power systems and investigates the theoretical operation of SOFCs with fuel mixtures resulting from different biogas lean upgrading pathways. Therefore, starting from ten mixtures including CH4, CO2, H2, H2O, N2, and O2, the study proposes a method to assess their impact on the electrochemical performance, degradation, and energy equilibrium of SOFC units. The model embeds thermodynamic equilibrium, the Nernst potential, and energy balance, enabling a comprehensive comparison across these three analytical domains. The findings underscore the unsuitability of dry biogas and dry biomethane due to the potential risk of carbon deposition. Moreover, mixtures incorporating CO2, with or without H2, present significant thermal balance challenges. [ABSTRACT FROM AUTHOR]

Public opinion significantly influences discussions on the selection of technologies for future energy systems. Our goal was to support the development of energy scenarios by evaluating decision-making criteria and energy-production alternatives at a national level. The importance of the criteria and the determination of energy-production preferences were based on a social survey conducted in European countries. However, public opinions on specific technologies are frequently based on limited knowledge and can vary depending on the context. In our study, we analyzed the comparative data sets from an international survey on energy sources using three approaches: direct ranking, a comparison using various criteria, and classifying the knowledge of technologies. The evaluated results not only provide an excellent opportunity for the development of energy scenarios but also enable policymakers to develop more effective communication strategies to inform the public about technological choices and raise awareness of the need for modifications to the energy system. [ABSTRACT FROM AUTHOR]

Efforts are intensifying to identify new biofuel sources in response to the pressing need to mitigate environmental pollutants, such as greenhouse gases, which are key contributors to global warming and various worldwide calamities. Algae and microalgae present themselves as excellent alternatives for solid-gaseous fuel production, given their renewable nature and non-polluting characteristics. However, making biomass production from these organisms economically feasible remains a challenge. This article collates various studies on the use of lignocellulosic waste, transforming it from environmental waste to valuable organic supplements for algae and microalgae cultivation. The focus is on enhancing biomass production and the metabolites derived from these biomasses. [ABSTRACT FROM AUTHOR]

Global warming is a vital problem that many researchers tried to solve with so many solutions such as: reducing electricity production with conventional generators by using renewable energy resources and using hydrogen as an alternative to fossil fuels. The universal Economic crisis came across to cut off certain quantities at scheduled times. This, directly, affects renewable energy sources connected to the grid due to voltage and frequency variations. To solve this dilemma, in this paper, the grid-connected solid oxide fuel cell (SOFC) model which is fed by green hydrogen to produce AC power, is developed by an Adaptive neuro-fuzzy inference system (ANFIS). It is one of the artificial intelligence applications to improve grid-connected SOFC dynamic response. ANFIS is mathematically presented and simulated using MATLAB/SIMULINK. The results show that the ANFIS controller has succeeded in enhancing most of the desired control and operation signals. [ABSTRACT FROM AUTHOR]

The Kingdom of Saudi Arabia (KSA) is facing extreme gas emissions challenges in the energy and transport sector. So, it is always preferred to use fuels that should be derived from waste to energy resources that are available abundantly without harmful environmental emissions. This experimental study uses neat diesel, and waste fat chicken oil blends to investigate the performance and emissions parameters in high-pressure common-rail multi-cylinder diesel engines. The tested fuel blends are prepared with the ratios of 10% biodiesel–diesel 90% (DB10), 15% biodiesel–diesel 85% (DB15), and 20% biodiesel–diesel 80% (DB20). The experimental results showed that, at 2000 rpm, torque and brake power produced by DB10 is 7.93% and 6.1% greater than the other diesel fuel due to its high heating value and density. The decrease in CO (16.66%), CO2 (10.79%), and HC (10.79%) emissions of DB10 compared to other diesel fuels was due to better ignition quality, higher oxygen content, and proper combustion. DB10 showed a slight increase in NOx emission (0.39%) compared to DF. Therefore, it is concluded from the performance and emission results that the DB10 is the most suitable alternative fuel compared to diesel, DB15, and DB20, and it can be used in the KSA without any modification in diesel engines. [ABSTRACT FROM AUTHOR]

As energy systems transition from fossil fuels to renewable sources, energy infrastructure will become a predominant land use, especially in rural areas. This poses a challenge for municipalities who need to adapt land use planning frameworks to more renewable energy. Using plan quality evaluation, this paper assesses how 57 rural official plans in Manitoba (Canada) are attempting to integrate energy planning. Consideration of energy within plans is poor, especially for implementation mechanisms and fact base. While rural communities are the forefront of the energy transition, existing land use planning frameworks are maladapted to enable it. [ABSTRACT FROM AUTHOR]

A current topic that has surfaced among Public Transport Companies (PTCs) is the selection of alternative fuels for their bus fleets. Both European and Italian regulations are pushing toward abandoning diesel fuel and the consolidation of alternative traction power sources, such as battery-electric vehicles, fuel-cell electric vehicles, and hydrogen-electric vehicles. The literature has provided some approaches toward assessing this selection such as multicriteria-decision-methods in some countries in the world. However, not enough specific attention has been paid to cost criteria, experts involved, and the type of service required. This paper intends to address these gaps by applying an integrated method, which includes: (i) the Analytical Hierarchy Process (AHP) to define the weights of criteria; (ii) the ELimination Et Choix Traduisant la REalitè I (ELECTRE I) to find a good compromise solution among the fuel alternatives and (iii) a simple Weighted Sum Model (WSM) to refine ranking. This integrated method was applied in Italy involving a panel of experts from whom the data was collected. Different fuel alternatives for both urban and interurban services and with and without funding are discussed. The results provide a useful tool supporting PTC policies, which aims to rationalise and prioritise bus fuel alternatives when deciding on fleet renewal. • Bus fuel selection studies lack cost criteria, experts involved, and service type. • The multicriteria-decision-methods (MCDM) considers the previous issues. • An integrated MCDM method selects fuel alternatives for urban/interurban bus services. • Results prioritise the economically advantageous fuels for with and without funding. [ABSTRACT FROM AUTHOR]

Methanol is favored for its excellent physicochemical properties, becoming an ideal alternative fuel for engines. Adopting a dual-fuel injection mode of methanol port injection and gasoline direct injection (MPI + GDI) allows for more flexible injection strategies, enhancing the engine's power, efficiency, and emission performance. However, observing the processes of fuel injection, atomization, mixing, flow, and combustion in real engine cylinders is challenging, and controlling the fuel–air distribution and turbulence before engine ignition is difficult. Therefore, after validating the simulation model through optical engine bench experiments, this study investigated the performance and emission characteristics of MPI + GDI engines under various injection strategies. The results indicate that delaying the GDI injection timing decreases the uniformity of the fuel–air mixture and reduces cylinder pressure, corresponding to a retarded crank angle. Increasing GDI injection pressure enhances the fuel–air mixing, especially when the injection timing is later. Employing secondary injection and increasing the proportion of the second injection lead to poorer fuel–air uniformity in the cylinder, a decrease in peak pressure value, reduced nitrogen oxides (NOx) emissions, and a gradual increase in carbon monoxide (CO) and total hydrocarbons (THC). [ABSTRACT FROM AUTHOR]

Strict emission regulations together with reducing fossil fuels resources lead to more attention on new combustion strategies and alternative fuels such as biodiesel which is renewable, environmentally friendly and more cost-effective than other fuels. In this study, CONVERGE CFD software coupling with chemical kinetics mechanism is used to numerically investigation of natural gas (NG)/biodiesel dual fuel engine. The discussed biodiesel consists of 25% methyl decanoate (MD), 25% methyl-9-decanoate (MD9D) and 50% diesel. A comparative study of NG/diesel and NG/biodiesel fueled cases is performed to highlight the combustion characteristics of biodiesel. For all simulated cases, it is supposed that 5% of energy is supplied by high reactive fuel (i.e., Diesel or Biodiesel) and 95% is coming with low reactive fuel (i.e., Natural Gas). Results revealed that in full load condition, using biodiesel/NG led to 86% lower carbon monoxide (CO) and 91% unburned hydrocarbons (UHC). On the other hand, peak pressure and maximum in-cylinder temperature increased 5% and 83 K, respectively which led to 0.6% efficiency improvement. according to the results of different injection timing, when it was advanced from -4 to -20 crank angle degree after top dead center (CAD ATDC) for biodiesel/NG and diesel/NG, the indicated mean effective pressure (IMEP) and gross thermal efficiency (GTE) reached at their peaks 18.3 bar and 48.2% at -12 CAD ATDC, 18.05 bar and 47.7% at -8 CAD ATDC respectively. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Engineering (17264073) is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Engineering (17264073) is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study investigates the extent and efficiency of global energy transition by examining the impact of renewable electricity generation on non-renewable electricity generation in 73 economies from 1990 to 2020. This is done to empirically scrutinise the assumption of perfect displacement as adopted by Intergovernmental Panel on Climate Change and other environmental and economic analysts. The estimated models also control for the effects of globalisation, economic growth, and international crude oil prices. The PMG-ARDL estimation demonstrates that renewable energy is able to partly displace the non-renewable energy and that the global energy transition is far from perfect displacement. More specifically, the coefficient of renewable energy generation is − 0.157, indicating that more than 6 units of alternative energy are necessary for displacing one unit of fossil fuel energy at the global level. However, the findings reveal that globalisation, economic growth, and crude oil prices negatively influence the energy transition by pushing up the non-renewable energy generation. To delve into finer details, the ARDL findings uncover that 1% increase in globalisation, economic growth, and crude oil prices increases the non-renewable energy generation by 0.88%, 0.75%, and 0.03%, respectively. The Driscoll–Kraay and feasible generalised least squares estimation techniques also confirm these baseline findings. Potential policy implications for enhancing the efficiency of global energy transition are also discussed. [ABSTRACT FROM AUTHOR]

The abundance and renewability of lignocellulosic biomass have made it a suitable alternative to fossil fuels in the reduction of global warming. The complex nature of the cellulose–hemicellulose–lignin bonds in the biomass makes it difficult to directly obtain platform chemicals. Pretreatment of the biomass has become a solution to remove lignin and obtain cellulose and or hemicellulose to produce platform chemicals. Platform chemicals such as hydroxymethylfurfural, furfural, and levulinic acid are viable feedstocks for aldol condensation to produce C8–C15 fuels. This review reports on deep eutectic solvents and microwave‐assisted pretreatment as green techniques for the delignification and platform chemicals production. Emphasis is placed on the use of hydrotalcites (HTs) as catalysts in platform chemicals production and aldol condensation for C8–C15 alkane fuels. Additionally, the hydrogenation of furfural into cyclopentanone and successive conversion into C10 and C15 alkanes with HTs was reviewed. [ABSTRACT FROM AUTHOR]

This study examines the adoption of Power Purchase Agreements (PPAs) and Renewable Energy Certificates (RECs) as strategic tools for decarbonization in the oil and gas sector. Focusing on the 21 largest oil and gas companies across Europe, North America, and South America, the analysis reveals varied adoption rates and strategic emphases between regions. European companies exhibit robust integration of PPAs and RECs to expand renewable energy capacities and reduce emissions, aligning closely with aggressive EU climate policies. In contrast, American companies show a cautious approach, focusing more on emission reduction from existing operations than on renewable expansions. The study's findings indicate that, while both regions are advancing in their decarbonization efforts, European companies are leading with more defined renewable energy targets and comprehensive low-carbon strategies. This research contributes to understanding how different regulatory environments and market conditions influence corporate strategies towards sustainable energy transitions in traditionally hard-to-abate industries. [ABSTRACT FROM AUTHOR]