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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]

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]

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]

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]

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]

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]

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.

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 The low-bias current–voltage technique was utilized to study charge transport in single-stranded DNA (ssDNA), assessing the method’s effectiveness for future studies aimed at estimating the degree of mutation or DNA damage. In the paper, we showed that charge carrier transfer processes in ssDNA can be precisely monitored using low-bias currents. We used negative differential resistance and the Fowler-Nordheim model to differentiate the charge transport mechanisms observed in a device composed of gold electrode-thiol-ssDNA junctions. It was possible to distinguish the processes at the two junctions (Au/thiol and thiol/DNA) due to their distinct current–voltage characteristics. We observed positive charge carrier tunneling, which we attribute to oxidation and reduction processes in the nucleobases of the ssDNA. Our results suggest that even minor changes in DNA chains can be accurately detected using the described methodology.

The tofu industry is one of the industries that has grown and developed a lot in Indonesia to meet the community's food needs. In the tofu production cycle, many activities have the potential to produce emissions that are harmful to the environment, one of which is greenhouse gases (GHGs). There are various activities carried out by the tofu industry to produce products that are ready for sale, starting from the procurement of raw materials, the production and distribution of tofu to the market. The longer the tofu production chain, the greater the potential to produce GHG emissions. To find out the amount of GHG emissions produced, it is necessary to take a tofu product life cycle (LCA) assessment. Therefore, this study aims to calculate the GHG emissions produced in the tofu production cycle in the X’s tofu industry. The results show that X’s tofu industry produces GHG emissions of 3,373.53 KgCO2eq per 300 kg soybean which originate from the use of electricity, gasoline, firewood, and liquid waste. Every activity carried out also contributes to the emergence of GHG emissions. The highest GHG comes from the use of firewood of 3,198.81 KgCO2eq, meanwhile, the stage that generates the most GHG is during the cooking stage. Alternative improvements that can be made to reduce emissions are minimizing the use of transportation equipment, minimizing water usage (water reduction), water reuse, converting the use of firewood to LPG, and utilizing liquid waste into biogas for the cooking process.

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.

The purpose of the study was to determine the effect of the fuel used in the spark-ignition engine of the selected vehicle on the characteristics of maximum torque and power at the crankshaft of the engine as a function of crankshaft speed and the content of components in the exhaust gas. The vehicle engine was tested on a stand equipped with V-tech VT-2/B2 chassis dynamometer, MAHA MET 6.3 exhaust gas analyzer and engine parameter monitoring system using OBD standard. The tests used two commercial fuels with different test octane number (RON) values of 95 and 100 octanes. Measurement of the characteristics of the maximum torque, power on the crankshaft and the total power losses in the drive system, the contact of the wheels with the rollers of the dynamometer and the dynamometer as a function of the crankshaft rotational speed was carried out using the acceleration method with a dynamic load comprising the braking torque of the rotating masses and the electro-swirl brake. On the basis of the test results, engine and drive system parameters of the vehicle using the software for generating driving test runs “the calculation of gearshift points for the WLTC cycle”, a set of measuring points determining the values of the engine crankshaft speed and the torque generated by the engine crankshaft was determined. The parameters of the selected engine operating conditions are within the ranges specified by the software for generating the selected test runs. The content of selected exhaust gas components (carbon monoxide CO, carbon dioxide CO2, other hydrocarbons HC, oxygen O2, λ coefficient, nitrogen oxides NO and nitrogen dioxide NO2) was measured for the selected operating parameters of the vehicle for the tested fuels. On the basis of the results of the toxicity measurements, analytical models determining the content of individual components in the exhaust gases as a function of the crankshaft rotational speed and the torque generated on the crankshaft and software simulating the exhaust emissions of the selected vehicle moving under dynamic conditions were developed.

The concept of Short-lived Climate Pollutions (SLCPs) has been developed as part of global warming mitigation policies to identify human-made atmospheric compounds that contribute to positive radioactive forcing. Numerous evident shows that there are impact getting from those pollutants like climate change. Despite the extensive research in this area, the potential emissions of SLCPs from the waste management sector at the city level have not been thoroughly explored. This study aims to reveal the material flow of domestic waste in Semarang City. The waste management system was assessed using a literature survey and the potential emissions of SLCPs from waste management were analysed from a life cycle assessment perspective. This study used Emission Quantification Tool (EQT), developed by the Institute for Global Environmental Strategies (IGES), to calculate greenhouse gas emissions from domestic solid waste management. While collecting data from existing literature, the author performed a MFA for the current conditions, which is based on the latest available data from 2022. The result showed that the current waste management system in Semarang City has several issues, such as a significant amount of unmanaged waste and the burning of waste, which contribute to high emissions of SLCPs. For the first time, this study demonstrates that by implementing advanced technologies such as incinerators and separating organic from inorganic waste, it is possible to achieve a substantial reduction in black carbon and methane emissions in Semarang City. These findings offer valuable insights for policymakers and contribute to the development of tailored waste management strategies that effectively mitigate SLCP emissions, setting a precedent for other urban areas facing similar challenges.

The concept of short-lived climate pollutions (SLCPs) has been developed as part of global warming mitigation policies to identify the human-made atmospheric compounds that contribute to positive radioactive forcing. Numerous evident shows that there are those pollutants cause negative impact like climate change. Despite the extensive research in this area, the potential emissions of SLCPs from the waste management sector at the city level have not been thoroughly explored. This study aimed to reveal the material flow of domestic waste in Semarang City. The waste management system was assessed using a literature survey and the potential emissions of SLCPs from waste management were analysed from a life cycle assessment perspective. This study used emission quantification tool (EQT), developed by the Institute for Global Environmental Strategies (IGES), to calculate the greenhouse gas emissions from domestic solid waste management. While collecting data from existing literature, the author performed a MFA for the current conditions, which is based on the latest available data from 2022. The result showed that the current waste management system in Semarang City has several issues, such as a significant amount of unmanaged waste and the burning of waste, which contribute to high emissions of SLCPs. For the first time, this study demonstrated that by implementing advanced technologies such as incinerators and separating organic from inorganic waste, it is possible to achieve a substantial reduction in black carbon and methane emissions in Semarang City. These findings offer valuable insights for policymakers and contribute to the development of tailored waste management strategies that effectively mitigate SLCP emissions, setting a precedent for other urban areas facing similar challenges. [ABSTRACT FROM AUTHOR]

The importance of studying particulate matter lies in its detrimental impact on human health and the environment. Industrial emissions often carry substantial dust content, necessitating the reduction of their environmental release. This study introduced a laboratory-scale photoelectric precipitator to assess its effectiveness in curbing particle emissions under varying temperature, humidity, and residence time conditions. This device operates in two stages: firstly, it charges particles by exposing copper wire surfaces to ultraviolet rays, generating photoelectrons in the airflow; secondly, it utilizes a positively charged collector surface for absorption and collection. Assessment under different temperature, residence time, and humidity conditions revealed that the system designed for 10 μm diameter particles displayed the highest efficiency. At 150℃, the removal efficiency was 39.55%, rising to 41.34% at 60% humidity and 43.58% with an 18-second residence time. Furthermore, increasing energy consumption from 144 j/l to 720 j/l resulted in a 10.93% efficiency increase, highlighting the correlation between energy input and system efficiency. High particulate matter levels diminish visibility, harm the climate, ecosystems, materials, and contribute to respiratory and cardiovascular ailments. These findings underline the photoelectric precipitator's potential in mitigating particulate matter's adverse effects on health and the environment. However, further research is warranted to optimize system design and explore additional parameters' impact on performance, ensuring its effectiveness in industrial processes to reduce particulate matter emissions. [ABSTRACT FROM AUTHOR]

This research examined trends in total greenhouse gas (GHG) emissions and GHG per capita of 120 countries across four continents from 2016 to 2022. It also investigated the impact of changes in countries' emissions on carbon pricing (CP) prices. The findings revealed a significant increase in CP prices, while the world's total GHG emissions rose modestly. The study highlighted the influence of both total GHG and GHG per capita on CP prices, with the latter exerting a stronger influence. The research also identified China as the most polluted country, followed by the USA and India. Notably, only the USA managed to reduce its total GHG emissions, while China and India increased theirs. From a regional perspective, Africa and Asia experienced significant increases in total GHG emissions, while European and North American countries saw slight decreases. Our analysis underscores the importance for countries to be early adopters of green energy technology in order to benefit from the economies of scale associated with this innovative technology before other nations, thereby achieving a long-term advantage in the energy industry. [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.

ObjectiveTo improve the combustion, performance and emissions of high-power marine engines, diesel fuel micro-injection with methanol ignition is adopted to study the in-cylinder combustion and emission characteristics. MethodsA three-dimensional simulation model of a diesel micro-injection pilot-ignition methanol engine is established on the basis of an ACD320 high-power marine medium-speed diesel engine in order to study the effects of injector parameters (nozzle number and methanol spray angle γ) on the combustion performance and emission characteristics of a marine large-bore methanol engine.ResultsWith the increase in the number of nozzle, the in-cylinder methanol atomization improves and the in-cylinder work mass mixing becomes more adequate, leading to the advancement of CA50 and the shortening of the combustion duration. While this yields higher indicated thermal efficiency（ITE） and a better equivalent indicated specific fuel consumption (EISFC), as well as contributing to the reduction of soot emissions, it also causes the elevation of NOx emissions. Moreover, as the methanol spray angle increases, the ITE increases, obtaining better fuel economy and lower soot emissions. With the optimal methanol spray angle (γ = 60°), the methanol spray is located in front of the diesel spray injection point, the flame propagation speed in the cylinder is faster, the indicated thermal efficiency is at its maximum and the fuel combustion is fuller, thereby obtaining the lowest soot emissions and most optimal EISFC.ConclusionThe results of this analysis can provide a theoretical basis for engine injector parameters.

In order to obtain the influencing rule of secondary combustion on emissions and combustion oscillation characteristics of gas turbine axial staged combustor in non-premixed combustion mode and explore a load increasing mode with stable low emission, an axial staged combustor for F-class gas turbines is selected for experimental study. The results show that CO consumption is restrained and CO emission increases sharply when secondary fuel is added at a lower combustor outlet temperature. The addition of secondary fuel and the increase of secondary equivalence ratio lead to the reduction of NOx emission, but the increase of load can weaken the ability of secondary fuel to reduce NOx emission. The addition of secondary fuel and the increase of secondary equivalence ratio restrain the combustion oscillation in the low frequency band (75—90 Hz). When the secondary equivalence ratio is higher than a certain threshold (0.19), the addition of secondary fuel can restrain higher frequency(175—210 Hz) combustion oscillation. In addition, by comprehensively considering the influence of secondary combustion on emissions and combustion oscillation, the operating range and load increasing mode of low emissions and stable combustion of axial staged combustor in the higher load range (20%—50% load) are obtained, which provides a reference for stable low emission operation of the unit during load increasing.

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 (SO 2 ) 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 SO 2 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 SO 2 emission that resulting in an average value of 777.4 kg/h. The realized correlation o between the SO 2 emission and parameters such as moisture, sulfur in lignite (total and organic), and high thermal, has increased the accuracy of SO 2 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 SO 2 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 SO 2 emissions.

The study aimed to explore the effects of biomass co-firing of coal using acacia wood bark at circulating fluidized bed (CFB) boiler coal-fired power plant with 110 MWe capacity. The analysis focused on main equipment parameters, including the potential for slagging, fouling, corrosion, agglomeration, fuel cost, and specific environmental factors. Initially, coal and acacia wood bark fuel were blended at a 3% mass ratio, with calorific values of 8.59 MJ/kg and 16.59 MJ/kg, respectively. The corrosion due to chlorine and slagging potential when using wood bark was grouped into the minor and medium categories. The results showed that co-firing at approximately 3% mass ratio contributed to changes in the upper furnace temperature due to the variation in heating value, high total humidity, and a less homogeneous particle size distribution. Significant differences were also observed in the temperature of the lower furnace area, showing the presence of a foreign object covering the nozzle, which disturbed the ignition process. A comparison of the seal pot temperature showed imbalances as observed from the temperature indicators installed on both sides of boiler, with specific fuel consumption (SFC) increasing by approximately 0.17%. During the performance test, the price of acacia wood bark was 0.034 USD/kg, resulting in fuel cost of 0.023355 USD/kWh, adding 0.061 cent/kWh to coal firing cost. Despite co-firing, the byproducts of the combustion process, such as SO2 and NOx, still met environmental quality standards in accordance with government regulations. However, a comprehensive medium- and long-term impact evaluation study should be carried out to implement co-firing operations using acacia wood bark at coal-fired power plant. Based on the characteristics, such as low calorific value, with high ash, total moisture, and alkali, acacia wood bark showed an increased potential to cause slagging and fouling.

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 This research tries to establish the emissions diffusion model of high-speed motor vehicles on the Capital Ring Expressway (CRE) around Beijing, China, applying the MOVES and the CALPUFF models. Data required for this study have been collected from different sources. The results show that small buses and large trucks have the highest pollutant emissions on the CRE. The pollutants like CO and HC mainly comes from gasoline vehicles, while NOx, PM10 and PM2.5 comes from diesel vehicles. The average concentrations of the diffusion of CO, NOx, CH4, PM10, and PM2.5 along with the CRE are 6.5 mg/m3, 2.3 mg/m3, 0.27 mg/m3, 0.055 mg/m3 and 0.056 mg/m3 respectively. The results of this study have practical significance and influence on the emission reduction and concentration control strategies under different circumstances, and put forward suggestions on changing transportation modes, strengthening supervision and so on. It has produced a number of recommendations for the policy makers including (1) active promotion of new energy vehicles on expressways, (2) strategic change of the mode of passenger and freight transportation on expressways, (3) strengthen traffic management and supervision of motor vehicles on expressways, and (4) strengthen vegetation protection in rural and ecologically sound areas along the route.

Abstract The scavenging process significantly affects the combustion and emission performance of marine low-speed two-stroke dual-fuel engines. Optimizing scavenging air pressure and temperature can enhance the engine's combustion efficiency and emission control performance, thereby achieving more environmentally friendly and efficient operation of dual-fuel engines. This study focuses on marine low-speed two-stroke dual-fuel engines, analyzing the effects of scavenging air pressure (3.0 bar, 3.25 bar, 3.5 bar, and 3.75 bar) and scavenging air temperature (293 K, 303 K, and 313 K) on engine performance and emission products. The results indicate that scavenging air pressure has a greater impact on engine performance than scavenging air temperature. An increase in scavenging air pressure leads to higher thermal efficiency and power. As the scavenging air pressure increases from 3 to 3.75 bar, the indicated thermal efficiency (ITE) increases from 44.02 to 53.26%, and indicated mean effective pressure (IMEP) increases by approximately 0.35 MPa. Increased scavenging air pressure improves nitrogen oxide (NOx) and hydrocarbons (HC) emissions. For every 0.25 bar increase in scavenging air pressure, NOx emissions decrease by 3.53%, HC emissions decrease by 33.35%, while carbon dioxide (CO2) emissions increase by 0.71%. An increase in scavenging air temperature leads to lower ITE and IMEP. As the air temperature changes from 293 to 313 K, the ITE decreases by approximately 1%, and IMEP decreases by about 0.04 MPa. Increased scavenging air temperature improves CO2 emissions. For every 10 K increase in the air temperature, the CO2 emissions decrease by 0.02%, while NOx emissions increase by 4.84%, HC emissions increase by 34.39%. Therefore, controlling scavenging air pressure is more important than scavenging air temperature in the operational management of marine two-stroke engines. Higher power and lower NOx and HC emissions can be achieved by increasing the scavenging air pressure.

Sandwich composite is an important part of engineering products capable of replacing metallic composite. It consists of two types of material, namely polypropylene honeycomb core and skin made from jute fiber-reinforced epoxy composite (JFRP), which are joined with glue. This study presented a unique discussion about adhesives that focused on the burning rate and emission performance of SA-A and SD-E. The burning rate performance was assessed with the UL-94 HB test in accordance with the ASTM D 635 standard. Emission value of both adhesives was also examined in line with the ASTM D 2863 standard using a Gasboard-3100P Syngas analyzer. In addition, FTIR and SEM analyses were used to determine the characteristics of the SA-A and SD-E adhesives. The results showed a significant difference in adhesives rates, with SA-A burning 0.5% faster than SD-E in addition to a 0.58% reduced weight loss. Emission test confirmed that both adhesives have similar LOI values of 22.6% and 22.8%, respectively. SA-A adhesives contained LSD, which is dangerous to human health. In conclusion, SD-E adhesives should be used on sandwich composite due to its epoxy-based potential as a flame retardant because SA-A adhesives has more potential to trigger firing due to the fuel content.

Argemone mexicana L. is an invasive alien plant species (IAPS) that belongs to Papaveraceae family. This study aimed to identify and map its current and future (2050 and 2070) potential distribution in South Wollo, Ethiopia. Eight Kebeles were selected using a stratified random sampling method that covered two agro-ecologies ranging 1500–3200masl for species presence data collection and 204 presences data were used for modelling. Climate, topography, and land use land cover change (LUCC) variables were used to build the species distribution model (SDM). An ensemble SDM model was run consisting of five algorithms into one single model. The area under the curve (AUC) and true skill statics (TSS) of the ensemble SDM score values of 0.89 and 0.7, respectively. The predicted result on its agro-ecological distribution showed 76.75% was non-suitable and 23.26% was suitable in varied extents, currently. Suitability will be increased after LUCC and climate change except the SSP5–8.5 2070 emission scenario. It will be highest under SSP1–2.6, 2050, and SSP2–4.5, 2070 emission scenarios possessing 28.67% and 28% suitability class, respectively. A. mexicana distributed in the mid and highland agro-ecologies from 1500–3200masl both in current and future time period. It urges effective coordination among actors to minimize its distribution potential.

ABSTRACT: Enteric CH4 produced from dairy cows contributes to the emission of greenhouse gases from anthropogenic sources. Recent studies have shown that the selection of lower CH4-emitting cows is possible, but doing so would be simpler if performance measures already recorded on farm could be used, instead of measuring gas emissions from individual cows. These performance measures could be used for selection of low emitting cows. The aim of this analysis was to quantify how much of the between-cow variation in CH4 production can be explained by variation in performance measures. A dataset with 3 experiments and a total of 149 lactating dairy cows with repeated measures was used to estimate the between-cow variation (the variation between cow estimates) for performance and gas measures from GreenFeed (C-Lock, Rapid City, SD). The cow estimates were obtained with a linear mixed model with the diet within period effect as a fixed effect and the cow within experiment as a random effect. The cow estimates for CH4 production were first regressed on the performance and gas measures individually, and then performance and CO2 production measures were grouped in 3 subsets for principal component analysis and principal component regression. The variables that explained most of the between-cow variation in CH4 production were DMI (R2 = 0.44), among the performance measures, and CO2 production (R2 = 0.61), among gas measures. Grouping the measures increased the R2 to 0.53 when only performance measures were used, and to 0.66 when CO2 production was added to the significant performance measures. We found the marginal improvement to be insufficient to justify the use of grouped measures rather than an individual measure because the latter simplifies the model and avoids over-fitting. Investigation of other measures that can be explored to increase explanatory power of between-cow variation in CH4 production is briefly discussed. Finally, the use of residual CH4 as a measure for CH4 efficiency could be considered by using either DMI or CO2 production as the sole predicting variables.

This study examines the impact of sharding on the scalability and efficiency of blockchain systems, specifically in the development of a complex of intelligent information and communication systems for environmental monitoring of emissions into the environment for decision-making in the context of carbon neutrality. Utilizing the Ikarus Network infrastructure, sharding was implemented on masternodes as a key technology to optimize transaction processing. Sharding enables the blockchain to be divided into multiple parallel chains, significantly increasing throughput and reducing the load on individual nodes. The results demonstrate a 70% increase in transaction processing speed, allowing the system to handle up to 5000 transactions per second, compared to the previous 3000 transactions per second. Network throughput increased by 50%, ensuring more efficient load distribution and stable operation even with high data volumes. Statistical analysis using ANOVA confirmed significant improvements in transaction processing speed, confirmation time, and resource usage post-sharding implementation. The F-value for transaction processing speed was 4567 with a P-value of 0.0001, indicating substantial improvements. Visual data analysis further confirmed these results, showing noticeable performance enhancements in the blockchain system. Distribution charts and histograms of transaction processing speed and confirmation time revealed an increase in the average number of transactions per second and greater system stability post-sharding. Sharding not only increased throughput but also enhanced system security by decentralizing data among shards, complicating potential cyberattacks. The study aimed to determine how sharding can improve the scalability and efficiency of blockchain systems. These improvements position the Ikarus Network as a promising solution for scalable and secure blockchain-based applications, especially for tasks related to carbon emission monitoring and management. These findings can underpin further study and the development of more efficient blockchain technologies.

Formulation of the problem. The transition from territorial-administrative to basin-based water resources management in Ukraine requires an assessment of the load of water bodies with pollutants from diffuse and point sources. Among the various components of the chemical composition of water entering water bodies, organic matter and nutrients are the most important. The Danube is the second largest river in Europe, with a basin covering the territories of 19 countries and is an important transportation waterway. Within Ukraine, the Danube is divided into the Lower Danube sub-catchment and the Tisza, Prut, and Siret River basins within the Carpathian region. The scientific results presented in this paper were obtained during research within the framework of state budgetary research works of the UHMI, the implementation of which will contribute to the further development of knowledge in the field of hydrometeorology. The results presented in the publication are important for supplementing information when writing the Danube River Basin Management Plan, which is being developed in accordance with Ukraine's obligations under the Association Agreement with the European Union. Aim of the study. To calculate the supply of nutrients and organic matter from diffuse sources to the rivers of the Danube basin within the Ukrainian Carpathians. Methods. Monitoring data of organic substances and nutrients provided by the Danube Hydrometeorological Observatory (the state surface water monitoring network of the State Emergency Service of Ukraine) for 2018 were used for calculations. To assess the load of water bodies by diffuse sources, a conceptual scheme was developed that allowed to take into account the main pathways of substances supply, i.e precipitation; water runoff from arable land, forests, meadows and pastures, built-up areas, rock outcrops, as well as from the population of rural regions without sewage systems. Scientific novelty. For the first time: the load of nutrients and organic matter in the Danube rivers within the Ukrainian Carpathians by the sources of their income was evaluated; it was found that agricultural land is the main source of emissions of inorganic nitrogen and phosphorus compounds. Practical value. The analysis of the diffuse load by nutrients and organic matter in the Danube rivers can be used as an important part of the River Basin Management Plan. The results of the calculations can also be used to develop measures to achieve certain environmental objectives. Results. The main source of organic matter in the water of rivers of the Carpathian region ere agricultural enterprises locating within rural settlements that are not equipped with sewage systems. Surface water of Prut and Tisza River basins is the most polluted by organic matter. By source, the nutrient emissions are distributed as follows. For the Tisza and Prut rivers, more than 50% of the total nitrogen compounds emissions come from agricultural land, while for the Siret River the source of nitrogen compounds are forests (46% of the total nitrogen emissions). Accordingly, the total phosphorus runoff for the Tisza and Prut rivers was distributed as follows: the dominant share (up to 45%) comes from agricultural land, the load caused by population not connected to the sewerage systems is 36%. For the Siret River, agricultural land and forested areas are of equal shares (33%) among the sources of phosphorus compounds.

Tambun Bungai street is located between Ahmad Yani and Diponegoro street. It has a significant level of congestion due to the presence of several schools, view place of worship and District Public Hospital. Motor vehicle activity produces exhaust gas emissions that cause air pollution resulting in a decrease in air quality. The purpose of this research to determine the magnitude of motor vehicle exhaust gas emissions in Tambun Bungai street and compare the results of the analysis of total vehicle emissions with permitted air quality standards. The methods are traffic counting survey and spot speed survey, then the analyze using an empirical calculation. Based on the results of the analysis it is known that the largest emissions of light vehicles occurring on Tambun Bungai street are CO of 1783,15 ppm and HC of 229,95 ppm at 07.45-08.00, PM of 7,14 and NOx of 29,68 pphm at 07.00-07.15. Then for the largest emissions of heavy vehicles occurred on Tambun Bungai street are CO of 0,63 ppm, HC of 0,28 ppm, PM of 257,80 and NOx of 82,71 pphm at 07.00-07.15. Overall the result of emissions total that compared to permitted quality standard shows that the results of the analysis of each type of pollutant exceeded the permissible air quality standards. These results can illustrate the amount of pollution that occurs and has exceeded the specified threshold so that the government can make policies that can be minimized it.

Since the International Maritime Organization has paved the way towards zero emissions, more frequent applications of transition fuels in newly constructed ships have been observed. Fuels such as LNG or methanol are characterised by lower emissions when burned in engines. In order to diminish fuel consumption, and hence the rate of emission, support for the performance of a ship’s engines with energy from renewable sources such as photovoltaic (PV) installations is increasingly common. The efficiency of PV panels decreases with an increase in temperature, and it is therefore important to cool them. However, the cooling systems for PV panels impose additional financial outlays as well as a higher demand for electric power, which is needed to run the circulating pumps. A natural cooling process can occur in some vessels via high sea waves, when the ship’s decks are flooded by outboard water, although such cooling has an accidental and periodic character, as it results from weather conditions. Despite this, its potential demands a closer examination. This paper presents experimental research carried out with an experimental setup that allowed us to simulate the process of flooding of a PV panel with water waves of various frequencies, resulting from choppy periods at sea. Depending on the weather conditions and the character of flooding, our results indicate that an increase in the power of the PV module of about 18% is obtainable. Our research shows that when the intervals between flooding are longer, the periodic character of the temperature changes obtained by flooding the front surface of a PV panel with water is more distinctive.

Abstract Exhaust emissions, which count among the most common causes of premature death worldwide, can cause irreversible changes in cells, leading to their damage or degeneration. In this research, L929 line cells were observed after exposure in the BAT-CELL chamber to exhaust gases emitted from a Euro 6 compression-ignition engine. Real road traffic conditions were simulated, taking into account air resistance while driving at speeds of 50 km/h, 120 km/h and idling engine. Morphological analysis of the cells was performed using an environmental scanning electron microscope. It has been observed that diesel exhaust fumes can cause inflammation, which can induce apoptosis or leads to necrotic cell death. The impact of the vehicle exhaust gases can inhibit cell proliferation by almost three times. Moreover, a correlation has been observed between the speed of the inflammatory reaction in cells and the presence of specific hydrocarbon compounds that determine the toxicity of exhaust gases. Research has shown that the toxicity of the emitted exhaust gases has been the highest at the driving speed of 120 km/h. In order to reduce the harmful effects of exhaust emissions, ecological alternatives and the supplementation of legal provisions regarding the compounds subject to limitation are necessary.

Environmental taxes ensure sustainable development, but their fiscal and environmental effectiveness differs for countries with different socio-economic characteristics. This study aims to compare the impact of environmental tax revenues on economy’s decarbonization (measured through carbon productivity – the ratio of GDP to carbon dioxide emissions) in different countries, considering their green technologies development and carbon emissions. The paper analyzed OECD and World Bank statistical data for 38 OECD countries for 2002–2021 using linear panel regression models with fixed and random effects (using Hausman test and STATA 18). To identify explicit and latent patterns of this influence, which are common to certain countries, this analysis did not consider each country separately but targeted clusters, distinguished by Ward and Sturges methods based on the effective tax rate on carbon emissions, total environmental tax revenues, total carbon emissions, and carbon productivity. The positive influence of environmental tax revenues on the economy’s decarbonization level has been confirmed for 29 countries (four from six clusters). The effect is the largest for the USA (an increase in tax revenues by 1% leads to an increase in carbon productivity by 0.9% on average) and the smallest – for the cluster including Austria, Belgium, Canada, Costa Rica, Czechia, Estonia, France, Germany, Hungary, Iceland, Korea, Lithuania, New Zealand, Poland, Portugal, Slovakia, Spain, and the Great Britain (increase – 0.1%). The negative impact was confirmed for nine countries (two from six clusters): Denmark, Finland, Israel, Latvia, and Sweden (decrease – 0.3%) and Greece, Italy, the Netherlands, and Slovenia (decrease – 0.21%).