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In the current research, the rare earth‐doped magnesium aluminate (MgAl2O4:Eu3+) spinels were produced by the combustion synthesis method. The employment of thermodynamic calculations revealed that the combustion approach is a proper way to synthesize MgAl2O4:Eu3+ material by urea fuel, although this procedure was fulfilled at 500°C, the final temperature will be around 2030°C. The x‐ray and FT‐IR spectra confirmed the successful formation of spinels, while it was shown that the calcination procedure results in a significant increase of crystallinity. On the other hand, it was interestingly seen that the addition of large amounts of Eu3+dopant (10 wt%) suppresses the crystallinity. The MAUD calculations interestingly revealed that the increase of Eu3+ dopant from 1 to 10 wt% leads to the increase of MgO and Al2O3 impurities. The related microstructural evaluations revealed that the particle size of the synthesized powders is mostly less than 40 nm which shows the superiority of combustion synthesis over other commercial methods. Also, the broadening of XRD peaks confirmed the formation of nano‐sized powder. The photoluminescence (PL) characterizations showed that doping of MgAl2O4 with 7 wt% Eu3+ brings the most intensive emission properties at the wavelengths of 592 and 617 nm. [ABSTRACT FROM AUTHOR]

In electrical power system engineering, the economic load dispatch (ELD) problem is a critical issue for fuel cost minimization. This ELD problem is often characterized by non-convexity and subject to multiple constraints. These constraints include valve-point loading effects (VPLEs), generator limits, emissions, and wind power integration. In this study, both emission constraints and wind power are incorporated into the ELD problem formulation, with the influence of wind power quantified using the incomplete gamma function (IGF). This study proposes a novel metaheuristic algorithm, the modified moth flame optimization (MMFO), which improves the traditional moth flame optimization (MFO) algorithm through an innovative flame selection process and adaptive adjustment of the spiral length. MMFO is a population-based technique that leverages the intelligent behavior of flames to effectively search for the global optimum, making it particularly suited for solving the ELD problem. To demonstrate the efficacy of MMFO in addressing the ELD problem, the algorithm is applied to four well-known test systems. Results show that MMFO outperforms other methods in terms of solution quality, speed, minimum fuel cost, and convergence rate. Furthermore, statistical analysis validates the reliability, robustness, and consistency of the proposed optimizer, as evidenced by the consistently low fitness values across iterations. [ABSTRACT FROM AUTHOR]

The paper presents experimental studies on the effect of co-combustion of aviation kerosene with hydrogen in the GTM400 turbojet engine on the change in the carbon footprint generated by the engine in relation to its standard operation without hydrogen in the fuel. This research is in line with current research and development trends carried out in the EU, linking them to the issues of the European Green Deal, the Fit for 55 directive and current environmental trends in aviation and energy. The main objective of the research was to check the effect of hydrogen co-combustion in a turbojet engine on the change of the carbon footprint, while a secondary objective was to verify the impact of higher exhaust gas temperatures generated by the new, high-calorific fuel on the secondary generation of nitrogen oxides (NOx), especially in the thermal mechanism, as an undesirable effect. The research shows that the co-combustion of hydrogen with aviation kerosene in a turbojet engine reduces the carbon footprint (reduction of CO2 maximum of 15% and CO emissions maximum of 24%), but also increases the emission of nitrogen oxides (NOx) maximum of 58%, including those generated in the thermal mechanism (significant increase in the temperature of exhaust gases), moreover, the increase in nitrogen oxide emissions is proportional to the amount of co-combusted hydrogen, which is directly related to the stoichiometry of the combustion process. The main conclusion of the research is that technologies for the combustion or co-combustion of hydrogen in turbojet engines require further research and development, mainly on the side of the use of excess exhaust gas temperature generated during combustion and methods of reducing secondary nitrogen oxides. [ABSTRACT FROM AUTHOR]

We investigate the terahertz (THz) scattering and emission properties of lunar regolith by modeling it as a random medium with rough top and bottom boundaries and a host medium situated beneath. The total scattering and emission arise from three sources: the rough boundaries, the volume, and the interactions between the boundaries and the volume. To account for these sources, we model their respective phase matrices and apply the matrix doubling approach to couple these phase matrices to compute the total emission. The model is then used to explore insights into lunar regolith scattering and emission processes. The simulations reveal that surface roughness is the primary contributor to total scattering, while dielectric contrasts between the volume and the boundaries dominate total emission. The THz emissivity is highly sensitive to the regolith dielectric constant, particularly its imaginary part, making it a promising alternative for identifying previously undetected water ice in the lunar polar regions. The THz emissivity model developed in this study can be readily applied to invert the surface parameters of lunar regolith using THz observations. [ABSTRACT FROM AUTHOR]

Gas turbines are widely used for power generation globally, and their greenhouse gas emissions have increasingly drawn public attention. Compliance with environmental regulations necessitates sophisticated emission measurement techniques and tools. Traditional sensors used for monitoring emission gases can provide inaccurate data due to malfunction or miscalibration. Accurate estimation of gas turbine emissions, such as particulate matter, carbon monoxide, and nitrogen oxides, is crucial for assessing the environmental impact of industrial activities and power generation. This study used five different machine learning models to predict emissions from gas turbines, including AdaBoost, XGBoost, k-nearest neighbour, and linear and random forest models. Random search optimization was used to set the regression parameters. The findings indicate that the AdaBoost regressor model provides superior prediction accuracy for emissions compared to other models, with an accuracy of 99.97% and a mean squared error of 2.17 on training data. This research offers a practical modelling approach for forecasting gas turbine emissions, contributing to the reduction of air pollution in industrial applications. [ABSTRACT FROM AUTHOR]

Conventional jet fuels derived from fossil sources contribute to greenhouse gas emissions and air pollution, leading to climate change. Recent studies have shown that biobased jet fuels from different feedstocks offer a more sustainable alternative to conventional fuels as they are derived from renewable biomass, reducing greenhouse gas emissions. The major feedstocks reviewed are jatropha curcas, camelina, karanja oil, waste cooking oil, and municipal solid waste. They offer diverse benefits for sustainable aviation fuel development. As a comparative analysis, this review examined jet fuel characteristics based on their physicochemical properties, namely energy content, viscosity, calorific value, cetane number, and freezing and flash points. The objective was to understand the influence of the properties on performance evaluation, environmental impact, and combustion characteristics. The properties of biojet fuels are compared with their fossil counterparts to validate their suitability as renewable alternatives and their benefits in terms of emissions reduction and engine performance. Biojet fuels perform better in terms of lower sulfur content, lower soot content, and a lower freezing point, their aromatic content, and their high cetane number. This study enhances the understanding of biojet fuels and their quality, and supports the development of sustainable fuel options. Overall, adherence to the American Society for Testing and Materials (ASTM) D7566‐18 standard is crucial for the acceptance and integration of biojet fuels into the aviation sector. Future research should explore feedstocks such as wood biomass, wastepaper, and agricultural residues for biojet fuels. It should also investigate the combustion and emission characteristics of biosourced aviation fuel at higher blending ratios (>50% by volume) with fossil Jet A‐1. [ABSTRACT FROM AUTHOR]

This study aims to address critical challenges such as global warming and energy sustainability by targeting the reduction of high NOx emissions in diesel engines. The effects of acetone (AC) and magnesium oxide (MgO) nanoparticles (NPs) as additives in improving the physicochemical properties of biodiesel derived from renewable, nonedible Pistacia terebinthus oil, which is abundant in Turkey and has a high free fatty acid (FFA) content of 5.8%, were investigated. Due to the high FFA content, a two‐step (esterification followed by transesterification [TR]) method was used for biodiesel production. Additionally, a quantitative analysis of biodiesel obtained by both single (TR) and two‐step methods was performed to address a gap in the literature. The addition of AC and MgO NPs to B20 (80% diesel fuel and 20% biodiesel) fuel resulted in reductions in the rate of pressure rise, instantaneous energy release, cylinder pressure, mean gas temperature, and cumulative heat release rate. However, brake‐specific fuel consumption increased, and brake thermal efficiency decreased. Emissions analyses showed a reduction in CO emissions by 6.65% with AC and 2.10% with AC + MgO, and a reduction in NOx emissions by 41.64% with AC and 46.03% with AC + MgO. However, hydrocarbon emissions increased by 26.48%. The study highlights the synergistic benefits of AC and MgO additives in biodiesel, presenting a viable strategy for improving the environmental and performance metrics of biodiesel blends. It provides new insights into alternative fuel formulations. [ABSTRACT FROM AUTHOR]

Air pollution, climate changes, and global warming are strongly correlated with burning huge amounts of petroleum fuels. Biodiesel has emerged as a promising alternative to alleviate these problems. Nonetheless, high density and viscosity, low energy content, and poor atomization of biodiesel restrict its widespread usage in diesel engines. The addition of nanoparticles (NPs) in biodiesel-based fuels has recently received considerable attention to modify the physicochemical properties of fuel as well as to improve the performance and emission characteristics of diesel engines. Among the various NP additives, alumina (Al2O3) NPs are of high interest owing to their excellent chemical and thermal stability, nontoxicity, high catalytic activity, etc. Hence, the present paper attempts to review the available literature concerning biodiesel fuels containing Al2O3 NPs. In this regard, the preparation techniques and physiochemical properties of these fuels including density, kinematic viscosity, cetane number, flash point, and calorific value are first discussed. Furthermore, the impact of Al2O3 NPs on the spray atomization and evaporation features of as-used fuels is investigated. Finally, the performance, combustion, and emission characteristics of diesel-fueled engines with Al2O3 NP-added biodiesel fuels are assessed. In conclusion, it was found that the use of Al2O3 NPs in biodiesel fuels can lead to enhanced engine performance by increasing the brake thermal efficiency, decreasing brake-specific fuel consumption, and lowering the emission of various harmful pollutants. The performance of Al2O3 nanoadditives for biodiesel-fueled diesel engines [ABSTRACT FROM AUTHOR]

Gasoline compression combustion engine has the advantages of low emission and high efficiency, which is very promising for research, but it is difficult to apply under low-load conditions. Gasoline has the characteristics of low reactivity; in the case of low thermodynamic state in the cylinder, the fire delay period of the fuel is longer, and the combustion phase is relatively lagging, which will lead to the increase of combustion cycle fluctuations, and even difficult to ignite and other adverse combustion phenomena. In order to improve the combustion stability of Gasoline Compression Ignition (GCI) engine under low-load condition and expand the limit of low-load combustion boundary, gasoline was reformed without catalyst under the boundary condition of reforming temperature of 488 K and reforming equivalent ratio of 8, and the concentration of reformed product was measured by a gas detection device. Subsequently, the coupling of the reformed product and spark plug with GCI engine under low-load condition was investigated to analyze the effect on engine combustion and emission. The results showed that the initial combustion timing of the low-load GCI engine was late, but the addition of reformed products could advance the combustion phase, shorten the combustion duration, reduce single-cycle NOx emission, and improve the small-load operation characteristics of GCI engine. Coupled spark plug ignition on the basis of adding reformed products could further improve the problem of combustion stability under low-load GCI engine. And the optimization effect became more obvious as the ignition position of the spark plug moves down. However, spark plug ignition would cause local high temperature areas, resulting in an increase in NOx emission. [ABSTRACT FROM AUTHOR]

This article reports on how management approaches influence methane emissions from landfills. The project team created various landfill operational scenarios for different regions of the planet with respect to waste composition, organic waste reduction and landfill gas recovery timing. These scenarios were modelled by applying a basic gas generation model according to the United Nations Intergovernmental Panel on Climate Change (IPCC) recommendations. In general, the IPCC's recommended modelling parameters and default values were used. Based on the modelling undertaken, two options stand out as being the most effective methane mitigation measures in a wide range of conditions throughout the world: (a) early gas recovery and (b) reduction of the amount of biodegradable organic waste accepted in a landfill. It is noted that reduction of organic input to any given landfill can take many years to realize. Moreover, suitable alternative processing or disposal options for the organic waste can be unaffordable for a significant percentage of the planet's population. Although effective, organic waste reduction cannot therefore be the only landfill methane mitigation measure. Early landfill gas recovery can be very effective by applying basic technologies that can be deployed relatively quickly, and at modest cost. Policymakers and regulators from around the globe can significantly reduce adverse environmental impacts from landfill gas emissions by stimulating both the early capture and flaring and/or energy recovery of landfill gas and programmes to reduce the inflow of organic waste into landfills. [ABSTRACT FROM AUTHOR]

In order to investigate particulate matter (PM) emission characteristics from the combustion of commercial biomass pellet, a fixed-bed reactor was used to conduct combustion experiments of wood dust, cotton stalk and bamboo dust. The particle size distributions and main element composition of PM were analyzed. And the influence of element content on PM emission was discussed. It was found that the yields of PM10 from high to low was cotton stalk, wood dust and bamboo dust, and the yields were 27. 76, 20. 83 and 9. 65 mg/ m3, respectively. The PMs were mainly composed of submicron particles (PM1 ), and the proportion of PM1 to PM10 was more than 90%. PM1 was mainly composed of alkali metal chloride and sulfide, while PM1-10 was mainly composed of compounds formed by calcium magnesium silicate. Correlation analysis showed that there was a positive correlated between biomass ash content and PM1 yield, while the content of Mg+Ca and n (Mg+Ca) / n (Si) were linearly correlated with PM1-10 yield. [ABSTRACT FROM AUTHOR]

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Syngas produced from glycerol using aqueous phase reforming for nickel-based catalysts with different support materials were tested in a compression ignition (CI) engine. Experiments were conducted using nickel–alumina, nickel–lanthanum (NL), and nickel–ceria catalysts at 1:1, 1:2, 1:3, and 1:4 glycerol–water ratios and temperatures of 240°C, 260°C, and 280°C. The NL catalyst showed the highest syngas and hydrogen yield of 90.58% and 76.42%, respectively, at 1:3 ratio and 260°C. The optimized NL syngas and diesel were tested in a CI engine at 6 to 30 lpm flow rates. At 30 lpm flow, brake thermal efficiency increased by 3.15%, NOx emission was reduced by 21.22%, and smoke lowered significantly compared to diesel. The faster hydrogen combustion in syngas increased the heat release rate and cylinder peak pressure. CO and HC emissions increased at lower loads due to diluted combustion but reduced at higher loads. NL showed the best performance and emissions among the syngases due to higher hydrogen content. In summary, the NL syngas at 30 lpm showed great potential in CI engines by improving combustion and performance and reducing emissions. [ABSTRACT FROM AUTHOR]

The precise preparation of hierarchical micelles is a fundamental challenge in modern materials science and chemistry. Herein, poly(di‐n‐hexylfluorene)‐block‐poly(3‐tetraethylene glycol thiophene) (poly(1m‐b‐2n)) diblock copolymers and polyfluorene‐block‐polythiophene‐block‐poly(phenyl isocyanide) triblock copolymers were synthesized using a one‐pot process via the sequential addition of corresponding monomers using a Ni(II) complex as a single catalyst for living/controlled polymerization. The crystallization‐driven self‐assembly of amphiphilic conjugated poly(1m‐b‐2n) led to the formation of nanofibers with controlled lengths and narrow dispersity. The block copolymers exhibited white, yellow, and red emissions in different self‐assembly states. By using uniform poly(1m‐b‐2n) nanofibers as seeds, introducing the polyfluorene‐block‐polythiophene‐block‐poly(phenyl isocyanide) triblock polymer as a unimer in the seed growth process, and adjusting the structure of the poly(phenyl isocyanide) block and the polarity of self‐assembly solvent, A−B−A triblock micelles, multiarm branched micelles, and raft micelles were prepared. [ABSTRACT FROM AUTHOR]

A series of highly emissive inert and chiral CrIII complexes displaying positive and negative circularly polarized luminescence (CPL) within the near-infrared (NIR) region at room temperature have been prepared and characterized to decipher the effect of ligand substitution on the photophysical properties, more specifically on the chiroptical properties. The helical homoleptic [Cr(dqp-R)2]3+ (dqp = 2,6-di(quinolin-8-yl)pyridine; R = Ph, ≡-Ph, DMA, ≡-DMA (DMA = N,N-dimethylaniline)) and heteroleptic [Cr(dqp)(L)]3+ (L = 4-methoxy-2,6-di(quinolin-8-yl)pyridine (dqp-OMe) or L = N2,N6-dimethyl-N2,N6-di(pyridin-2-yl)pyridine-2,6-diamine (ddpd)) molecular rubies were synthesized as racemic mixtures and then resolved and isolated into their respective pure PP and MM enantiomeric forms by chiral stationary phase HPLC. The corresponding enantiomers show two opposite polarized emission bands within the 700-780 nm range corresponding to the characteristic metal-centered Cr(2E'→4A2) and Cr(2T1'→4A2) transitions with large glum ranging from 0.14 to 0.20 for the former transition. In summary, this study reports the rational use of different ligands on CrIII and their effect on the chiroptical properties of the complexes. [ABSTRACT FROM AUTHOR]

Microalgae are considered to be a promising and prospective source of lipids for the production of biocomponents for conventional liquid fuels. The available sources contain a lot of information about the cultivation of biomass and the amounts and composition of the resulting bio-oils. However, there is a lack of reliable and verified data on the impact of fuel blends based on microalgae biodiesel on the quality of the emitted exhaust gas. Therefore, the main objective of the study was to present the emission characteristics of a compression-ignition engine fuelled with a blend of diesel fuel and biodiesel produced from the lipids accumulated in the biomass of a heterotrophic culture of Schizochytrium sp. The final concentrations of microalgal biomass and lipids in the culture were 140.7 ± 13.9 g/L and 58.2 ± 1.1 g/L, respectively. The composition of fatty acids in the lipid fraction was dominated by decosahexaenoic acid (43.8 ± 2.8%) and palmitic acid (40.4 ± 2.8%). All parameters of the bio-oil met the requirements of the EN 14214 standard. It was found that the use of bio-components allowed lower concentrations of hydrocarbons in the exhaust gas, ranging between 33 ± 2 ppm and 38 ± 7 ppm, depending on the load level of the engine. For smoke opacity, lower emissions were found in the range of 50–100% engine load levels, where the observed content was between 23 ± 4% and 53 ± 8%. [ABSTRACT FROM AUTHOR]

Water in the engine/combustion chamber is not a novel phenomenon. Even humidity has a major effect on internal combustion engine emissions and can thus be considered the first invisibly present emission technology. With modern techniques, the problematic aspects of water, such as corrosion and lubrication issues, seem to disappear, and the benefits of water's effect in combustion may also be enhanced in the context of EURO 7. The current study examines the literature on the effects of water on diesel combustion in chronological sequence, focusing on changes over the last three decades. Then it analyzes and re-evaluates the water effect in the current technology and the forthcoming Euro 7 regulatory context, comparing the conclusions with current automotive applications and mobility trends, in order to show the possible benefits and prospective research avenues in this sector. Techniques introducing water to combustion could be a major approach in terms of the EURO 7 retrofit mandate, as well as a feasible technique for concurrent nitrogen oxides and particulate reduction. [ABSTRACT FROM AUTHOR]

In this contribution we report on a novel approach towards luminescent light‐responsive ligands. To this end, cyanostilbene‐ guanidiniocarbonyl‐pyrrole hybrids were designed and investigated. Merging of a luminophore with a supramolecular bioactive ligand bears numerous advantages by overcoming the typical drawbacks of drug‐labelling, influencing the overall performance of the active species by attachment of a large luminophore. Here we were able to establish a simple and easily accessible synthesis route to different cyanostyryl‐guanidininiocarbonyl‐pyrrole (CGCP) derivatives. These compounds were investigated regarding their light‐responsive double bond isomerisation, their molecular structures in single crystals by means of X‐ray diffractometry, their emission properties by state of the art photophysical characterisation as well as bioimaging and assessment of cell toxicity. [ABSTRACT FROM AUTHOR]

The unique luminescence properties of gold nanoclusters (AuNCs) have attracted intense research interest in multiple areas. However, most AuNCs exhibit only a single-color emission. Achieving color-tunable emission through single AuNCs is attractive but still challenging. Herein, a switchable fluorescence strategy was introduced by integrating an aggregation-caused quenching (ACQ)-type ligand into an aggregation-induced emission (AIE)-type nanocluster system. In the AIE/ACQ strategy, 4,6-diamino-2-pyrimidinethiol (DPT)-AuNCs with color-tunable emission were developed: in the dimethylformamide (DMF)/water system, the DPT-AuNCs were dissociated and blue fluorescence was obtained, whereas in the MeOH/water system, DPT-AuNCs aggregated and strong orange phosphorescence was obtained. The emission color from orange to blue could also be switched by adjusting the solvent composition. Based on this strategy, the color-tunable AuNCs system was further employed for dynamic information encryption. [ABSTRACT FROM AUTHOR]

Microemulsion based fuels (MBF) have gained significant attention in recent years due to their potential to enhance combustion efficiency, reduce emissions, and improve overall engine performance. This research paper enlightens the effects of physiochemical properties on the emission characteristics of CI engine. The microemulsions are formulated using surfactants, co‐surfactants, water or alcohols, and fuel components. The effects of density, viscosity, calorific value, cold flow properties, and cetane number along with the stability and the multi‐component characteristics of (MBF) has been taken into consideration to examine its effects on Emission characteristics such as nitrogen oxides (NOx), sulfur oxides (SOx), carbon monoxide (CO), particulate matter (PM), and unburned hydrocarbons (UHC). Microemulsion‐based fuels lower emissions of NOx and PM, recognized to the more complete combustion. The review highlights various studies that have investigated the benefits of microemulsion fuels, including reduced emissions of different pollutants and thus reduce the adverse effect on environment. In conclusion, microemulsion‐based fuels show likely physiochemical properties, as well as favorable emission characteristics, with reduced NOx, SOx, CO, PM, and UHC emissions. This study highlights the potential of microemulsion‐based fuels as environment friendly alternatives, flagging the way for further research. [ABSTRACT FROM AUTHOR]

The growing demand of sustainable and environment friendly energy sources has spurred research and development efforts towards the integration of biofuels in various applications, particularly in internal combustion engines. Microemulsion technique is a new and innovative alternative to traditional fossil fuel that has gained a significant attention in recent years. This type of bio fuel is made by blending of small amount of biofuel and large amount of conventional diesel fuel. This review paper explores the potential of enhancing the performance of Compression ignition (CI) engines by incorporating additives into hybrid biofuels. The study focuses on the synergistic effects of combining traditional fossil fuels with bio‐derived components, such as ethanol, biodiesel, and other bio‐based additives. This review paper aim is to explore the performance of a 4‐stroke, single‐cylinder, direct injection Compression Ignition (CI) engine at different loads using different fuels blends like CNWEDB, BFNP150, PPNP150, and ME Diesel/Colza oil. The review outlines recent advancements in biofuel technology, including novel production methods and feedstock options, aiming to overcome limitations associated with conventional biofuels. The article aims to investigate the potential of vegetable oil in formulating MHBF, analyzing its performance and emissions in CI engines. The engine performance parameters viz., brake thermal efficiency brake specific fuel consumption have been reviewed and found that these values are comparable to the biodiesel blends with pure petrodiesel. At 60%, 80%, and full load condition the BTE of microemulsion diesel/colza oil is increasing while at 40%, 80%, and full load the BSFC is decreasing. Emissions reported by the various researchers, however, have a positive attribute with respect to NOx, CO, and UHC. At full load CO is decreasing and at all load conditions the value of UHC is decreasing. The paper concludes with a discussion on future research directions, emphasizing the need for continued innovation to address emerging issues and optimize the performance of CI engines for a sustainable and energy‐efficient future. [ABSTRACT FROM AUTHOR]

The use of biodiesel as an alternative to conventional diesel fuels has gained significant attention due to its potential for reducing greenhouse gas emissions and improving energy sustainability. This study explores the impact of TiO2 nanoparticles on the emission characteristics and combustion efficiency of biodiesel blends in compression ignition (CI) engines. The fuels analyzed include diesel, SB20 (soybean biodiesel), SB20 + 50 TiO2 ppm, SB20 + 75 TiO2 ppm, PB20 (palm biodiesel), PB20 + 50 TiO2 ppm, and PB20 + 75 TiO2 ppm. Experiments were conducted under a consistent load of 50% across engine speeds ranging from 1000 to 1800 RPM. While TiO2 nanoparticles have been widely recognized for their ability to enhance biodiesel properties, limited research exists on their specific effects on soybean and palm biofuels. This study addresses these gaps by providing a comprehensive analysis of emissions, including NOX, CO, CO2, and HC, as well as exhaust gas temperature (EGT), across various engine speeds and nanoparticle concentrations. The results demonstrate that TiO2 nanoparticles lead to a reduction in CO emissions by up to 30% and a reduction in HC emissions by 21.5% at higher concentrations and engine speeds. However, this improvement in combustion efficiency is accompanied by a 15% increase in CO2 emissions, indicating more complete fuel oxidation. Additionally, NOX emissions, which typically increase with engine speed, were mitigated by 20% with the addition of TiO2 nanoparticles. Exhaust gas temperatures (EGTs) were also lowered, indicating enhanced combustion stability. These findings highlight the potential of TiO2 nanoparticles to optimize biodiesel blends for improved environmental performance in CI engines. [ABSTRACT FROM AUTHOR]

In response to increasing environmental demands, modeling emissions from older vehicles presents a significant challenge. This paper introduces an innovative methodology that takes advantage of advanced AI and machine learning techniques to develop precise emission models for older vehicles. This study analyzed data from road tests and the OBDII diagnostic interface, focusing on CO2, CO, THC, and NOx emissions under both cold and warm engine conditions. The key results showed that random forest regression provided the best predictions for THC in a cold engine (R2: 0.76), while polynomial regression excelled for CO2 (R2: 0.93). For warm engines, polynomial regression performed best for CO2 (R2: 0.95), and gradient boosting delivered results for THC (R2: 0.66). Although prediction accuracy varied by emission compound and engine state, the models consistently demonstrated high precision, offering a robust tool for managing emissions from aging vehicle fleets. These models offer valuable information for transportation policy and pollution reduction strategies, particularly in urban areas. [ABSTRACT FROM AUTHOR]

Biofuel made from Syzygium cumini, often known as Jamun, has the potential to be a low-cost, sustainable, and emission-free alternative. In this work, we experimentally explore the performance of a compression ignition (CI) engine that burns a blend of hydrogen and biodiesel. Hydrogen is pumped into the air intake manifold by means of a hydrogen gaseous supplement that, when exposed to atmospheric conditions, co-combusts with a pilot flame ignited by Jamun oil. To investigate the impact of hydrogen supplementation on performance and exhaust emission, a variety of hydrogen–Jamun fuel mixture proportions are provided to the engine. The research demonstrates that adding hydrogen improves the thermal efficiency (5%) of diesel engines whereas lowering specific energy fuel consumption (4%) at fixed Jamun flow rates. The gas emission data demonstrates that when hydrogen (HC) emission (12%) supplements decreases, NOx emission (10%) increases somewhat but opacity (8%) increases significantly. The experiment demonstrates that hydrogen and Jamun duel fuel in compression ignition engines burn smoothly. [ABSTRACT FROM AUTHOR]

A new Cd(II) derivative, [Cd(2-Hstp)(Hbipy)2] (1), was obtained hydrothermally by the combination of Cd(NO3)2·4H2O as metal salt, the flexible aromatic carboxylate, 2-sulfoterephthalic acid (2-stp), and the N-donor ancillary ligand, 4,4′-bipyridine (bipy), as organic linker. Single crystal X-ray diffraction analysis revealed the molecular structure of the complex, in which the Cd(II) atoms show a distorted octahedral geometry. In the asymmetric unit, both the carboxylate and the N-donor connector bridge pairs of cadmium ions; this ultimately leads to the formation of a set of undulated sheets formed by fused rings comprising six cadmium centers, two bipy, and four 2-stp ligands. Considering each complex as a node, the supramolecular structure can be seen as a 6-c uninodal net of the type pcu, with point symbol {412.63} and vertex symbol [4.4.4.4.4.4.4.4.4.4.4.4.*.*.*]. The Cd(II) derivative endowed the material with moderate luminescent properties. Finally, the molecular geometry of 1 has been studied by DFT computation applying the B3LYP/def2-SVP level of theory. [ABSTRACT FROM AUTHOR]

Improving the quality of fuel represents an effective solution to address the long-standing issue of engine emissions. This study adopts CeO2 and carbon nanotubes as additives, which are blended with neat diesel using a physicochemical method to produce nanofuel. The research investigated the combustion and emission performance of a high-pressure common rail four-cylinder engine under various operating conditions, utilizing different types of nanomaterials, nanoparticle sizes, and biofuel substitutes as variables. The outcomes of the study indicate superior performance of the nanofuel compared with neat diesel across all evaluated aspects. Notably, the size of the added particles directly influenced the beneficial enhancements achieved in diesel fuel. Additionally, the nanofuel containing carbon nanotubes demonstrated a greater improvement effect than the one incorporating CeO2. Furthermore, when compared with neat diesel, the combustion of carbon nanotubes (CNT) nanofuel at 100% load resulted in a notable 4.0% increase in brake thermal efficiency, coupled with reductions of 3.0% in brake specific fuel consumption and 8.8%, 4.4%, 4.9%, and 9.6% reductions, respectively, for carbon monoxide (CO), hydrocarbons (HC), nitrogen oxides (NOx), and smoke emissions. It is noteworthy that the incorporation of biofuel alternatives, such as biodiesel and ethanol, into nanofuels exhibited even further enhanced effects in terms of promoting combustion and reducing emissions. The findings of this study serve as an important reference for selecting suitable nanofuels tailored to meet diverse operational demands of engines. [ABSTRACT FROM AUTHOR]

The importance of energy in the economic development of countries in transition is almost vital, especially in countries with large coal mineral resources, such as our country, Kosovo. Quantification and accurate analysis of sulfur dioxide (SO2) emissions from lignite power plants are done to inform environmental stakeholders, improve regulatory compliance, protect public health, improve emission control technologies, and support environmental practices. sustainable energy. This study investigated the quantification and accurate analysis of SO2 emissions from lignite power plants to inform environmental stakeholders, improve regulatory compliance, protect public health, improve emission control technologies, and support sustainable energy practices. The laboratory analyses performed with standard methods have resulted in different values for the parameters: Moisture, ash, and sulfur content in lignite is up to 45%, 20%, and 1.2% during the year 2023, through these results we have calculated the SO2 emission that resulting in an average value of 777.4 kg/h. The realized correlation o between the SO2 emission and parameters such as Moisture, sulfur in lignite (total and organic), and High thermal, has increased the accuracy of SO2 emission estimates, the components that are active components during the coal combustion process. Better estimates facilitate a more accurate assessment of the environmental impact of organic SO2 emissions, such as their role in acid rain formation and ecosystem damage. This assessment reflects the poor state of current lignite combustion technologies and suggests their improvement in terms of controlling SO2 emissions. [ABSTRACT FROM AUTHOR]

Renewable energy sources are becoming an increasingly viable alternative energy source for the near future due to increased environmental concerns and increasingly strict energy restrictions. Bioethanol and biodiesel are the most promising biofuel options. In the present study effects of spirulina microalgae biodiesel and diesel blends on compression ignition diesel engines at 1500 r/min utilizing various blends B20, B40, B60, B80, and B100, as well as B0 (diesel), 23.5° before top dead centre and 18.5 compression ratio (CR) at 220 bar. The extreme peak pressures of the engine for B0, B20, B40, B60, B80, and B100 were 103.13, 101.65, 100.25, 98.90, 96.74, and 94.83 bar, respectively. The percentage reduction in ignition delay duration for B20, B40, B60, B80, and B100 was 2.57%, 4.17%, 5.28%, 6.60%, and 8.16% compared to pure diesel. B20 proves to be the most promising biodiesel blend. Analysis of variance analysis was done for experimental data. The response surface method was used to optimize the engine performance and emission parameters for load, blend, and CR variations. Optimized input conditions were found as load 52.27, CR 18.5, and blend B20. The research dynamic analysis was carried out for the sustainability of biodiesel. [ABSTRACT FROM AUTHOR]

Brick manufacturing is a major global industry employing millions of workers, yet it remains heavily reliant on outdated, polluting technologies. This study aims to categorize the brick kilns according to the way each of them functions. Also, it focuses on the fuel used and its properties. Another goal of the current research is to bring out the effects brick industry has on the environment and the people who work and live near the brick kilns. Conclusively, the current study underscores the urgent necessity for improvement and for the adoption of the strategies outlined to guide the brick manufacturing field towards a more sustainable future. [ABSTRACT FROM AUTHOR]

In the current century, electrical networks have witnessed great developments and continuous increases in the demand for fossil fuels based energy, leading to an excessive rise in the total production cost (TPC), as well as the pollutant (toxic) gases emitted by thermal plants. Under this circumstances, energy supply from different resources became necessary, such as renewable energy sources (RES) as an alternative solution. This latter, however, characterized with uncertainty nature in its operation principle, especially when operator system wants to define the optimal contribution of each resource in an effort to ensure economic and enhanced reliability of grid. This paper presents an Enhanced version of Kepler optimization algorithm (EKOA) to solve the problem of stochastic optimal power flow (SOPF) in a most efficient way incorporating wind power generators and solar photovoltaic with different objective functions, the stochastic nature of wind speed and solar is modeled using Weibull and lognormal probability density functions respectively. To prove the effectiveness of the proposed EKOA, various case studies were carried out on two test systems IEEE 30-bus system and Algerian power system 114-bus, obtained results were evaluated in comparison with those obtained using the original KOA and other methods published in the literatures. Thus, shows the effectiveness and superiority of the efficient EKOA over other optimizers to solve complex problem. The incorporation of RES resulted in a significant 2.39% decrease in production cost, showcasing EKOA's efficiency with a $780/h, compared to KOA's $781/h, for IEEE 30-bus system. For the DZA 114-bus system revealed even more substantial reductions, with EKOA achieving an impressive 12.6% reduction, and KOA following closely with a 12.4% decrease in production cost. [ABSTRACT FROM AUTHOR]

ABSTRACT The present paper discusses the synthesis of unprecedented red‐emitting mono‐azo compound pyrazole azo fluorescent tag (PAFT) by a diazotization method, followed by an electrophilic substitution reaction. Further, the metal complex of PAFT is also prepared by refluxing the ethanolic solution of the ligand with the corresponding metal (RuCl3 and C4H6CuO4.H2O) salts under suitable experimental conditions. The synthesized fluorophore PAFT displays intense fluorescence in the aggregate state and has excellent qualities, including high purity, low cost, eco‐friendliness, and good photostability. These unique characteristics of PAFT led to the development of new fluorescence‐based technology for the in situ viewing of latent fingerprints. Various spectroscopic and analytical techniques are used to confirm the structural characteristics of the synthesized compounds, including UV–Vis, FT‐IR, (1H) NMR, HRMS, TGA, VSM, ESR, and powder XRD methods. The potency of the antibacterial activity of the compounds was evaluated. The results revealed that compound PAFT and [Ru(PAFT)Cl3] H2O showed excellent sensitivity at 0.8 μL/mL against the Gram‐positive bacteria Staphylococcus aureus. [ABSTRACT FROM AUTHOR]

2D van der Waals (vdW) layered materials exhibit significant exciton binding energy and versatile stacking options, making them ideal for room‐temperature exciton‐polariton devices used in low‐threshold lasing, nonlinear optical switching, and quantum computing. However, most existing systems depend on external optical microcavities coupled with single monolayers, leading to limited controllability and increased costs. Here, external cavity‐free vdW magnet CrSBr crystals are presented that feature magnetically controllable self‐hybridized exciton‐polaritons that remain stable up to room temperature. The ultrastrong exciton‐photon coupling suppresses donor‐, phonon‐, and defect‐related emissions. Furthermore, the exciton‐polariton dispersion and emission spectra can be effectively controlled by adjusting the magnetic field, temperature, and CrSBr thickness. This vdW exciton‐polariton material platform, demonstrating remarkable magnetic responsiveness in open cavity configurations under ambient conditions, paves the way for the development of compact, fast, and low‐loss spin, quantum, and magneto‐photonic devices. [ABSTRACT FROM AUTHOR]

• Estimates of modeled CH 4 emission (E) data for 1,325 U.S. landfills were reviewed. • Operators use two methods to estimate E from landfills with a gas collection system. • First-order decay (FOD) method shows increasing emissions. • Collection efficiency assumption method shows decreasing emissions. • FOD method shows some agreement to remotely sensed national estimates. As part of its commitment to the United Nations Framework Convention on Climate Change, the U.S. annually develops a national estimate of methane emissions from municipal solid waste (MSW) landfills by aggregating activity data from each facility. Since 2010, the U.S. has reported a 20 % decrease in MSW landfill emissions despite a 21 % increase in tons disposed. Operator-submitted data were investigated to understand the causes of this decline. In the U.S., operators of landfills with a gas collection and control system (GCCS) calculate their facility's emissions via two separate approaches – (1) first-order decay (FOD) and (2) collection efficiency assumption (CEA) − and select either result to feed into the annual inventory. The FOD model predicts methane generation proportional to waste disposal and that approach calculated a 19 % increase in total methane generated from 2010 to 2022, whereas generation via the CEA approach decreased by 8.9 %. The amount of measured methane collected has increased 7.5 % for the same years. Discrepancies between the two models' generated methane, assumed gas collection efficiencies, and oxidized methane compound into substantive differences in national estimates. Operators more frequently select the CEA method, which results in decreased national estimates. If only the FOD method was used, U.S. MSW landfill emissions would be 1.3-1.7 times greater than current estimates which is similar to recent extrapolations from remote sensing campaigns in the U.S. Both models contain parameters with large inherent uncertainty. Without measurement methods that continuously quantify both point-source and diffuse emissions, an assessment of either equation's accuracy cannot be made. [ABSTRACT FROM AUTHOR]

Abstract\nNOVELTY STATEMENTEnvironmental pollution, especially from coal-based thermal power plants, poses significant risks to human respiratory health and the environment. This study evaluates the diversity of lichens in the areas. Physiological and bioaccumulation responses of two crustose lichens (Bacidia incongruens and Rindoina sophodes) and one foliose lichen (Pyxine cocoes) in the vicinity of the Feroz Gandhi Unchahar National Thermal Power Corporation, Raebareli, Uttar Pradesh, India were also assessed. These lichens, exposed to emissions including fly ash, greenhouse gases, metals, and particulate matter were analyzed for metal accumulation and physiological responses. Changes in physiological parameters and metal profiles concerning distance from the coal-based thermal power plant to the outskirts were analyzed for B. incongruens, R. sophodes and P. cocoes by utilizing Inductively Coupled Plasma Mass Spectrometry (ICP-MS). The study identified 18 lichen species from 12 genera and 10 families in the area, with Pyxine sorediata newly recorded in Uttar Pradesh. The dominant species, B. incongruens, P. cocoes, and R. sophodes, preferred substrates like Mangifera indica, Acacia nilotica, and Azadirachta indica bark. Physiological analyses revealed variations in pigment concentrations, with significant differences in chlorophyll a, chlorophyll b, total chlorophyll, carotenoids, and chlorophyll degradation, while protein content remained stable. Metal accumulation studies showed nine metals with distinct patterns, B. incongruens had higher concentrations in the west (52730.61 µg g-1) and P. cocoes in the east (23628.32 µg g-1). Correlation analyses indicated significant relationships between paired elements, suggesting specific sources of environmental contamination. This research highlights the significance of integrating physiological and environmental factors to understand lichen responses to coal based thermal power plant.This study contributes significantly to lichenological and environmental monitoring by documenting the occurrence and physiological responses of lichen species in the vicinity of a thermal power plant. The study reports the Pyxine sorediata as a new addition to the lichen flora of Uttar Pradesh, India. Furthermore, the research comprehensively analyzes photosynthetic pigments and metal accumulation in Bacidia incongruens, Pyxine cocoes, and Rinodina sophodes. This study marks the first time these three lichen species have been compared based on their physiological characteristics and metal profiles, highlighting the difference between crustose and foliose lichen. The study uniquely correlated the physiological parameters and metal accumulation pattern of these lichen species with their spatial distribution around the coal-based Feroze Gandhi Unchahar National Thermal Power Plant. The detailed PCA analysis offers new insights into the distinct sources and distribution patterns of various metals in the environment. The novelty of the work also lies in the revival and focused study of lichen species to explore their responses to environmental stressors. By investigating the physiological, elemental distribution and bioaccumulation characteristics of both crustose and foliose lichens in the vicinity of thermal power plant, the research highlights the unique potential of these lichens as bioindicators. The approach not only provides critical insights into pollution levels and ecosystem health but also underscores the importance of lichens in environmental monitoring and conservation efforts. [ABSTRACT FROM AUTHOR]

The inlet valve closing (IVC) timing plays a crucial role in engine combustion, which impacts engine performance and emissions. This study attempts to measure the potential to use n-butanol (Bu) and its blends with the neat diesel in a common rail direct injection (CRDI) engine. The computational fluid dynamics (CFD) simulation is carried out to estimate the performance, combustion, and exhaust emission characteristics of n-butanol-diesel blends (0%-30% by volume) for variable valve timings. An experimental study is carried out using standard valve timing and blends to validate the CFD model (ESE AVL FIRE). After validation, the CFD model is employed to study the effect of variable valve timings for different n-butanol-diesel blends. Extended coherent flame model-3 zone (ECFM-3Z) is implemented to conduct combustion analysis, and the kappa-zeta-f (k-ζ -- f) model is employed for turbulence modeling. The inlet valve closing (IVC) time is varied (advanced and retarded) from standard conditions, and optimized valve timing is obtained. Advancing IVC time leads to lower cylinder pressure during compression due to reduced trapped air mass. The brake thermal efficiency (BTE) is increased by 4.5%, 6%, and 8% for Bu10, Bu20, and Bu30, respectively, compared to Bu0. Based on BTE, optimum injection timings are obtained at 12° before the top dead center (BTDC) for Bu0 and 15° BTDC for Bu10, Bu20, and Bu30. Nitrogen oxide (NOx) emissions increase due to complete combustion. Due to IVC timing, further carbon monoxide and soot formation decreased with blends and had an insignificant effect. [ABSTRACT FROM AUTHOR]

Developing the empirical method based on observation and experiment, Alhazen is considered the greatest Muslim physicist and the most significant figure in the history of optics between antiquity and the seventeenth century. Inventing a camera obscura, Alhazen rebuilt our conception of eyesight. His theory of vision was enormously prominent and much of our understanding of optics and light is based upon his groundbreaking discoveries. He began his criticism of emission by describing what happens when people are exposed to bright lights. No matter what the light source, the effect of bright lights was always the same. What this indicates to Alhazen is that light entering into the eye from an external source had some serious function in eyesight. Respecting observation, experiment and empirical method, Suhrawardi, the father of Illumination School, argues all theories of vision and rejects them just by mere reasoning. Suhrawardi validates his own Illuminationist method by scientists' empirical method. So, I will argue, he is not to deny empirical aspect of Alhazen's theory of vision. In an allegory, I will use the camera, representing the whole process of a human vision, while I use "beyond camera" for the embodiment that allows for the unfolding of a human soul's position in the process of vision. What Alhazen is speaking of, we might call the process within the camera; while what Suhrawardi is speaking of, we could name the process behind the camera. [ABSTRACT FROM AUTHOR]

Heated tobacco products (HTPs) are newly developed nicotine delivery systems via the inhalation of mainstream aerosols generated during the heating of tobacco leaf materials. Previous studies have shown that the amount of chemicals generated is much lower than that generated by conventional combustible cigarettes. However, little attention has been paid to formate, a conjugated base of formic acid with potentially toxic effects on human health. This study aims to understand the actual emission levels and behaviour of formate in mainstream aerosols produced by commercially available HTP devices in Japan. Aerosols were generated from four types of devices with regular and menthol-type flavours using a vaping machine following the CRM 81 puffing protocol. Formate was tapped in 5 mM sodium carbonate solution and subsequently analysed using ion chromatography. The results showed that the total emission amount of formate ranged from 0.0027 ± 0.0031 to 0.27 ± 0.055 mg L−1, varying with heating temperature and flavour type. Moreover, the majority of formate existed in a particulate form due to the weak-basic property of the aerosol, and the formate emission level was much greater than the workplace exposure limit for the direct inhalation of mainstream aerosols. The formate in the mainstream aerosol can be considered a health concern, when using "high-temperature type" HTPs over a long period. [ABSTRACT FROM AUTHOR]

Spectroscopic studies of Ho3+-doped SrF2 crystals were performed regarding applications in solid-state lasers. The crystal structure of the Ho:SrF2 crystal was investigated using single-crystal X-ray diffraction. SrF2 exists as a cubic structure with an Fm3m space group. A Raman shift of 288 cm–1 was observed for the Ho:SrF2 single crystal. SrF2 hosts with low-frequency vibrational modes are suitable for reducing nonradiative emissions while maximizing radiative emissions. The absorption spectrum was recorded in the visible region from 400 to 800 nm, yielding absorption lines at 416, 450, 468, 473, 484, 536, 638, and 643 nm. The fluorescence spectrum recorded at an excitation wavelength of 450 nm shows two emission bands at 546 and 656 nm, which correspond to green and red emission, respectively. The intensity parameters Ωλ (λ = 2, 4, and 6) were estimated using the Judd–Ofelt theory. For Ho:SrF2 single crystal, the calculated Ωλ are Ω2 = 0.14 × 10–20 cm2, Ω4 = 3.14 × 10–20 cm2, and Ω6 = 3.74 × 10–20 cm2. The radiative transition probabilities, radiative lifetimes, and branching ratios βR for Ho:SrF2 were determined using the Judd–Ofelt parameters. The 5S2 + 5F4 → 5I8 transition is more effective for population-building processes because of its lifetime (0.26 ms) and higher branching ratios (~82.86%). Ho:SrF2 is, therefore, a promising solid-state laser crystal for green and red spectral regions. [ABSTRACT FROM AUTHOR]

In the era of decarbonization driven by environmental concerns and stimulated by legislative measures such as Fit for 55, the industry and transportation sectors are increasingly replacing petroleum-based fuels with those derived from renewable sources. For many years, the share of these fuels in blends used to power compression ignition engines has been growing. The primary advantage of this fuel technology is the reduction of GHG emissions while maintaining comparable engine performance. However, these fuel blends also have drawbacks, including limited ability to form stable mixtures or the requirement for chemical stabilizers. The stability of these mixtures varies depending on the type of alcohol used, which limits the applicability of such fuels. This study focuses on evaluating the impact of eight types of alcohol fuels, including short-chain (methanol, ethanol, propanol) and long-chain alcohols (butanol, pentanol, hexanol, heptanol, and octanol), on the most critical operational parameters of an industrial engine and exhaust emissions. The engines being compared operated at a constant speed and under a constant load, either maximum or close to maximum. The study also evaluated the effect of alcohol content in the mixture on combustion process parameters such as peak cylinder pressure and heat release, which are the basis for parameterizing the engine's combustion process. Determining ignition delay and combustion duration is fundamental for optimizing the engine's thermal cycle. As the research results show, both the type of alcohol and its concentration in the mixture influence these parameters. Another parameter important from a usability perspective is engine stability, which was also considered. Engine performance evaluation also includes assessing emissions, particularly the impact of alcohol content on NOx and soot emissions. Based on the analysis, it can be concluded that adding alcohol fuel to diesel in a CI engine increases ignition delay (up to 57%), pmax (by approximately 15–20%), HRRmax (by approximately 80%), and PPRmax (by approximately 70%). Most studies indicate a reduction in combustion duration with increasing alcohol content (by up to 50%). For simple alcohols, an increase in thermal efficiency (by approximately 15%) was observed, whereas for complex alcohols, a decrease (by approximately 10%) was noted. The addition of alcohol to diesel slightly worsens the stability of the CI engine. Most studies pointed to the positive impact of adding alcohol fuel to diesel on NOx emissions from the compression ignition engine, with the most significant reductions reaching approximately 50%. Increasing the alcohol fuel content in the diesel blend significantly reduced soot emissions from the CI engine (by up to approximately 90%). [ABSTRACT FROM AUTHOR]

The present work aims to find a viable substitute fuel for diesel and control pollutants from compression ignition engines. Therefore, in the present investigation, an attempt has been made to study the effect of 20% proportion of five different biodiesel diesel blends in diesel engine. The 20% proportion of biodiesel such as Jatropha, Pongamia, Mahua, Annona and Nerium and 80% of diesel is denoted as J20, P20, M20, A20 and N20 are used in the present investigation. The experimental results showed that the different biodiesel blends' brake thermal efficiency is slightly lower compared to neat diesel fuel. However, the N20 blend has shown improvement in performance and reduction in exhaust emissions compared to other biodiesel diesel blends. From, the experimental work, it is found that biodiesel can be used up to 20% and 80% of a diesel engine without any major modification. [ABSTRACT FROM AUTHOR]

The experimental investigation aimed to determine how the use of biodiesel derived from dill and cresson oil affected the performance of semi-industrial burners. Furthermore, an investigation will be conducted to assess the combustion properties of different blends of biodiesel, specifically B10, B20, B40, and B60. The study looks at biodiesel's chemical makeup, physical properties, and how it works in the system that moves it to the burner and the burner simulator's burning process. Biodiesel exhibits comparable qualities to conventional diesel oil, enabling the possibility of blending it to achieve the desired ratio. The results suggest that increasing the percentage of biodiesel leads to a reduction in flame distance and a rise in flame temperature. Furthermore, the complete combustion of the fuel is responsible for the brilliant and transparent flame. Additionally, using dill and Cresson fuels that come from biodiesel raises the average flame temperature by about 17% and 16.1%, respectively, compared to regular diesel fuel. [ABSTRACT FROM AUTHOR]

The analysis of environmental impacts throughout the entire process of coal-fired power plants is imperative to implement effective measures for controlling and reducing pollutant emissions. However, there is still limited research focusing on the cradle-to-gate stage in the life cycle of coal-fired power plants and their environmental impact. This study employs a life cycle assessment (LCA) methodology to assess the environmental impacts of coal-fired power plants in South Sumatra. The primary environmental impact categories of primary emissions include CO2, SO2, NOx, and CH4. The most significant environmental impacts arise from CO2 emissions, notably 98.46% from land clearing and preparation and 86.74% from overburden removal and coal extraction. These stages primarily contribute to global warming throughout the cradle-to-gate process. Sulfur dioxide emissions from land clearing activities are the main contributor to acid rain, followed by overburden removal and coal extraction (96.51%) and coal stockpiling (1.48%), which also play a role. The release of NOx from land clearing and preparation, overburden removal, and coal stockpiling contributes to the potential for eutrophication. Land clearing and preparation have a significant impact on global warming during the coal mining and distribution stages. Practical measures such as enhancing emission reduction facilities and increasing pollutant emission standards for each process are necessary to promote environmentally friendly coal-fired power plants. [ABSTRACT FROM AUTHOR]

Petroleum-based fuels are generally used in internal combustion engines. Petroleum-based fuels now have difficulty meeting Euro standards in terms of emissions. That's why different methods are used. One of these is that adding natural gas to fuels can be beneficial in reducing emissions and increasing engine performance. In the experimental study, the engine performance and emissions of adding natural gas at different rates (50, 100, 150 and 200 g/h) into the intake air of an engine using gasoline fuel at different torque values (5, 10, 15 and 20 Nm) at a constant 3000 rpm were examined. The engine used in the study is a Lombardini LGW 523 MPI gasoline two-cylinder engine. When the experimental results are examined, the addition of natural gas to gasoline fuel reduces fuel consumption. The lowest values in specific fuel consumption were obtained when natural gas was added. Emissions decreased with increasing torque. As the natural gas addition rate increased, the thermal efficiency increased. [ABSTRACT FROM AUTHOR]

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In order to reduce global warming, new energy fuels that use waste biomass to replace traditional coal are rapidly developing. The main purpose of this study is to investigate the feasibility behavior of different biomass materials such as spent coffee grounds (SCGs) and spent tea grounds (STGs) as fuel during combustion and their impact on the environment. This study involves using fuel shaping and co-firing methods to increase the fuel calorific value and reduce the emissions of pollutants, such as NOX and SO2, and greenhouse gas CO2. The produced gas content was analyzed using the HORIBA (PG-250) laboratory combustion apparatus. The results indicate that, among the measured formed particles, SCG:STG = 8:2, 6:4, and 4:6 had the lowest post-combustion pollutant gas emissions. Compared to using only waste coffee grounds as fuel, the NOx emissions were reduced from 166 ppm to 102 ppm, the CO emissions were reduced from 22 ppm to 12 ppm, and the CO2 emissions were reduced from 629 ppm to 323 ppm. In addition, the emission of SO2, the main component of acid rain, was reduced by 20 times compared to the combustion of traditional fuels. The SO2 emission of five different proportions of biomass fuels was 5 ppm, which is much lower than that of traditional coal fuels. Therefore, SCG and STG mixed fuels can replace coal as fuel while reducing harmful gasses. [ABSTRACT FROM AUTHOR]

Methane is a powerful greenhouse gas with a 25 times higher 100-year warming potential than carbon dioxide and is a target for mitigation to achieve climate goals. To control and curb methane emissions, estimates are required from the sources and sectors which are typically generated using bottom-up methods. However, recent studies have shown that national and international bottom-up approaches can significantly underestimate emissions. In this study, we present three bottom-up approaches used to estimate methane emissions from all emission sectors in the Denver-Julesburg basin, CO, USA. Our data show emissions generated from all three methods are lower than historic measurements. A Tier 1/2 approach using IPCC emission factors estimated 2022 methane emissions of 358 Gg (0.8% of produced methane lost by the energy sector), while a Tier 3 EPA-based approach estimated emissions of 269 Gg (0.2%). Using emission factors informed by contemporary and region-specific measurement studies, emissions of 212 Gg (0.2%) were calculated. The largest difference in emissions estimates were a result of using the Mechanistic Air Emissions Simulator (MAES) for the production and transport of oil and gas in the DJ basin. The MAES accounts for changes to regulatory practice in the DJ basin, which include comprehensive requirements for compressors, pneumatics, equipment leaks, and fugitive emissions, which were implemented to reduce emissions starting in 2014. The measurement revealed that normalized gas loss is predicted to have been reduced by a factor of 20 when compared to 10-year-old normalization loss measurements and a factor of 10 less than a nearby oil and production area (Delaware basin, TX); however, we suggest that more measurements should be made to ensure that the long-tail emission distribution has been captured by the modeling. This study suggests that regulations implemented by the Colorado Department of Public Health and Environment could have reduced emissions by a factor of 20, but contemporary regional measurements should be made to ensure these bottom-up calculations are realistic. [ABSTRACT FROM AUTHOR]

An experimental investigation is carried out on conventional compression ignition engines' combustion, performance, and emission characteristics using Conventional Dual Fuel (CDF) combustion and reactivity-controlled compression ignition (RCCI) combustion strategies. The experiments are performed on a variable-speed production-grade diesel engine converted to a research engine. Comparative combustion analysis shows that RCCI combustion is more stable and shows a consistent ignition delay across all engine speeds. The exhaust gas temperature of RCCI combustion is lower than that of CDF combustion and is in the range of Conventional Diesel Combustion (CDC). CDC shows better brake thermal efficiency (BTE) than CDF and RCCI combustion across all engine speeds, followed by RCCI combustion. The lowest BTE is observed in CDF combustion. Emission results show that RCCI combustion produced significantly lower NOx emissions than CDC at low engine speed without much HC and CO emissions increment. RCCI combustion does not effectively reduce NOx emissions and produces higher HC and CO emissions at high engine speeds. A BTE-NOx trade-off analysis is also carried out, demonstrating the suitability of RCCI combustion at low engine speed. CDC under high engine speed conditions and in the transition region of medium engine speed CDF combustion is more favorable to reduce NOx emission.