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Reports on the results of a questionnaire administered to 14- and 15-year-old students (n=1637) in 25 British schools concerning their views on how car exhaust emissions affect global environmental problems. Children's beliefs discussed include the connection of car exhaust to global warming, the greenhouse effect, acid rain, and the ozone layer. (Author/AIM)

Effective separation of linear and branched C6 alkanes is of importance in the improvement of the research octane number of gasoline during the isomerization of linear alkanes. However, developing a novel material for this separation remains a challenge. Activated crystals with a collapsed "channel-like sorption site" by assembling p-bromothiacalix[4]arene propyl ether molecules after removing cyclohexane (CyC6) molecules that act as templates are classified as a nonporous adaptive crystal. The activated crystals are capable of storing branched alkanes such as isohexane (2-C6), 3-methylpentane (3-C6), and 2,2- and 2,3-dimethylbutane (2,2- and 2,3-C6) vapors in the single-component system. In contrast, no sorption of n-hexane (n-C6) as one of the linear alkanes was observed. In these branched alkanes, the crystals preferentially adsorbed more branched alkanes, specifically 2,2-C6 and 2,3-C6, compared to mono-branched alkanes like 2-C6 and 3-C6 in two-component systems. Surprisingly, slight adsorption of n-C6 was observed in the system. The retention capacity of mono- and di-branched and linear alkanes in the crystals follows the order: 2,2-C6 ≈ 2,3-C6 > 3-C6 > 2-C6 ≫; n-C6. [ABSTRACT FROM AUTHOR]

In the present work, a lot of efforts have been made to reduce the sulfur particles, as main pollutants, from gasoline with using cerium (Ce) and Al(NO3)3 nano composites measured with Reference method: ASTM D7039‐15. The sulfur crystallite number was around 7235 ppm for DS (Ni (NO3)2 and urea). These unwanted sulfur particles reached to 3028 ppm for y (Al (NO3)3)/x (Ce)=0.25 in weight ratio, without using centrifuge process. This result is a very good due to some points: The present experimental works have been done at the room temperature and atmosphere environment, whilst many other works, as addressed here, have needed higher temperature and pressures. To our knowledge, Ce, Aluminum nitrate and urea as nano composite materials have need been used for desulfurization processes. Moreover, some relevant techniques such as X‐ray powder diffraction (XRD), Energy dispersive X‐ray analysis (EDX), Fourier Transform Infrared (FTIR) spectroscopy, X‐ray photoelectron spectroscopy (XPS), UV‐Vis spectroscopy, transmission electron microscopy (TEM), and Dynamic light scattering (DLS) have also been used. [ABSTRACT FROM AUTHOR]

In the case of CO2 thermal‐catalytic hydrogenation, highly selective olefin generation and subsequent olefin secondary reactions to fuel hydrocarbons in an ultra‐short residence time is a huge challenge, especially under industrially feasible conditions. Here, we report a pioneering synthetic process that achieves selective production of high‐volume commercial gasoline with the assistance of fast response mechanism. In situ experiments and DFT calculations demonstrate that the designed NaFeGaZr presents exceptional carbiding prowess, and swiftly forms carbides even at extremely brief gas residence times, facilitating olefin production. The created successive hollow zeolite HZSM‐5 further reinforces aromatization of olefin diffused from NaFeGaZr via optimized mass transfer in the hollow channel of zeolite. Benefiting from its rapid response mechanism within the multifunctional catalytic system, this catalyst effectively prevents the excessive hydrogenation of intermediates and controls the swift conversion of intermediates into aromatics, even in high‐throughput settings. This enables a rapid one‐step synthesis of high‐quality gasoline‐range hydrocarbons without any post‐treatment, with high commercial product compatibility and space‐time yield up to 0.9 kggasoline ⋅ kgcat−1 ⋅ h−1. These findings from the current work can provide a shed for the preparation of efficient catalysts and in‐depth understanding of C1 catalysis in industrial level. [ABSTRACT FROM AUTHOR]

This paper takes the catalytic cracking unit of a petrochemical industry as an example to explore the effects of blending hydrogenated tail oil on the distribution and quality of catalytic cracking products, and analyzes the reasons. The results showed that blending hydrogenated tail oil can significantly reduce the output of dry gas and oil slurry. Every increase of 1 ton of hydrogenated tail oil refining, the output of oil slurry decreases by 0.14 tons, dry gas decreases by 56 m³, and gasoline output increases by 0.26 tons. The blending of hydrogenated tail oil will reduce the aromatic hydrocarbon content in gasoline components, decrease the density of gasoline components, and lower the distillation temperature. As the blending amount of hydrogenated tail oil increases, the C3 content in the liquefied petroleum gas decreases and the C4 content increases . This is attributed to the fact that the blending of hydrogenated tail oil inhibits the deep reaction of catalytic cracking, reduces the generation of C3 and below components and deep cracking products such as slurry, and increases the yield of liquids above C4. As the blending amount of hydrogenated tail oil increases, C3 and C4 components become the boundary line for the impact of hydrogenated tail oil blending on the depth of catalytic cracking reaction. [ABSTRACT FROM AUTHOR]

The car market in Mexico has undergone substantial change over the last twenty years, as sales have increased dramatically and as policy measures have been introduced to improve fuel economy so that decarbonization targets can be achieved. The argument presented in this paper is that overall fuel economy is driven by vehicle sales and the fuel economy standards imposed. In addition, this picture is complicated by the purchasing preferences of buyers, and this might reduce the effectiveness of the policy measures introduced. A case study approach allows analysis of the shifts in transport policy (2003–2020) to be undertaken by linking the fuel consumption of cars (L/100 km) to the purchasing patterns of consumers, and from this estimate the levels of CO2 emissions. From the empirical analysis, it is found that, although there have been fuel economy gains every year, this is countered by (a) increasing sales of SUVs, and (b) a car market that is increasingly being dominated by larger cars. The current fuel standards are not sufficient to control the continued growth in fuel consumption, and levels of carbon emissions are continuing to increase. In conclusion, tighter emissions standards are needed, together with stronger governance structures and a range of further policy measures to improve car efficiencies and limit growth of the use of larger vehicles. [ABSTRACT FROM AUTHOR]

The OLS and ridge regression (RR) estimators are adversely affected, when the problem of multicollinearity and y-direction outliers occur together. The robust ridge regression with penalized parameters offers biased estimators with lower variance than OLS and RR. The optimal penalized parameter value is crucial for balancing variance and bias. This study proposes three new weighted robust penalized M-estimators to address both multicollinearity and y-direction outliers. Their performance is evaluated against OLS, RR and existing penalized M-estimators using Monte Carlo simulations based on mean squared error (MSE). The new estimators exhibit lower MSE in the presence of multicollinearity and y-direction outliers. A real data application on gasoline consumption demonstrates the superior performance of the new estimators. [ABSTRACT FROM AUTHOR]

An efficient stable electrochemical method for the determination of thiophene as a sulfur model compound in gasoline has been investigated based on the electrodeposition of graphene oxide and dicyandiamide on graphite electrode by cyclic voltammetry. The electroactive layer performance was considered by linear sweep voltammetry and square wave voltammetry by examining scan rates and their relevant equations to evaluate the electrochemical parameters. This modified electrode has high electrocatalytic characteristics to irreversible electrooxidation of thiophene. The electron transfer coefficient (α) was equal to 0.78, the electron transfer rate constant (log KS) was 3.2 s−1, and the saturated adsorptive capacity of the electroactive substance at the electrode surface (Γmax) was 1.14 × 10−8 mol cm−2 at pH 8 at low working potential of 0.5 V versus Ag/AgCl reference electrode. Scanning electron microscopy of the surface revealed the nanostructure of electrodeposited films and the morphology. This sensor is capable of electrochemical response to thiophene over the concentration range from 25 to 250 nmol L−1 with a detection limit of 8.31 nmol L−1, and a quantification limit of 25.18 nmol L−1. The method's reliability was checked regarding the simulated gasoline samples and the desired response and sensitivity were provided. The wide dynamic range, low detection limit, favorable precision and accuracy, and fast response with no interferences confirm the ability of this sensor for thiophene determination. This nano-sensor can be used for electrochemical in-situ direct monitoring of liquid fuel desulfurization processes. [ABSTRACT FROM AUTHOR]

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This study experimentally investigated the influence of gasoline injection pressure (GIP) on the performance and hydrogen knock limit of a gasoline direct-injection hydrogen–gasoline dual-fuel engine. The GIP was varied from 50 to 140 bar, and hydrogen was introduced at a step size of 2 LPM until knock onset at spark timings of 4° and 12° CA before top dead center (BTDC). The hydrogen knock limit was extended at a higher GIP, with maximum hydrogen flow rates of 10 and 16 LPM at 12° CA and 4° CA BTDC, respectively. Increasing the GIP and retarding the spark timing negatively affected brake thermal efficiency, brake mean effective pressure, and in-cylinder pressure. The CO 2 and NO x emissions decreased, and the CO emissions increased with an increase in the GIP. The cyclic variation increased considerably with GIP. However, hydrogen blending exhibited a completely opposite trend to that of GIP. • Study of the effect of gasoline injection pressure in a hydrogen-gasoline dual fuel engine. • The hydrogen knock limit was influenced by the variation in gasoline injection pressure. • Increasing the gasoline injection pressure showed a negative effect on the performance and combustion characteristics. • Cyclic variation increased at higher gasoline injection pressure and reduced with hydrogen blending. • Increased hydrogen flow rate was observed at higher gasoline injection pressure and retarded spark timing. [ABSTRACT FROM AUTHOR]

As ethanol production increases and the demand for gasoline in spark ignition engines decreases over the next few decades, the use of these fuels in compression ignition systems is expected to increase. This raises the question of how much ethanol-in-gasoline is the right blend for compression ignition. This work experimentally studied E10, E30, E50, E75, and E100 in a split injection partially premixed compression ignition strategy. It was found that, separately, the cool flame reactivity of E10 and the high cooling potential of E75 and E100 enable heat release rate control in partially premixed combustion. E30 and E50 did not show the same control authority. E30 performed the worst due to having a small amount of cool flame reactivity and a low cooling potential. It was found that NOx emissions were not significantly impacted by ethanol content, but the smoke emissions were. E100 produced near zero smoke, but all the ethanol-gasoline blends produced some smoke. When 20% of the fuel was injected during the mid-dle of the compression stroke, E10, E30, E50, and E75 all produced low, but nonzero smoke emissions. When the second injection was moved near top dead center, the smoke emissions of E75 stayed low but the smoke emissions of E10, E30, and E50 all rose to a filter smoke number greater than 0.3. These results indicate that low- and high-ethanol content gasolines are both viable paths forward for partially premixed combustion systems, but medium-ethanol content gasolines should be avoided. [ABSTRACT FROM AUTHOR]

Petroleum-derived products like petrol, containing complex hydrocarbons, have catastrophic environmental effects, posing a universal challenge. Bioremediation is known as eco-friendly and safe technique for removal of hydrocarbon pollutants. In this study, indigenous bacteria were isolated from oil contaminated soils and screened for their biodegradation potential. The bacterial enrichment and isolation were done using selective media Bushnell-Haas supplemented with petrol as a sole carbon source. Out of fifteen isolated strains best two isolates S4P2 and S14P1 were selected on basis of DCPIP screening method. These isolates were identified as Pseudomonas chengduensis & Pseudomonas donghuensis by 16S rRNA gene sequencing. The growth parameters were optimized by one factor at a time. The optimum growth temperature for P. chengduensis & P. donghuensis was found to be 37°C at pH 7 with a substrate concentration of 1%. [ABSTRACT FROM AUTHOR]

Ultra‐high‐speed synchrotron‐based hard X‐ray (i.e. above 10 keV) imaging is gaining a growing interest in a number of scientific domains for tracking non‐repeatable dynamic phenomena at spatio‐temporal microscales. This work describes an optimized indirect X‐ray imaging microscope designed to achieve high performance at micrometre pixel size and megahertz acquisition speed. The entire detector optical arrangement has an improved sensitivity within the near‐ultraviolet (NUV) part of the emitted spectrum (i.e. 310–430 nm wavelength). When combined with a single‐crystal fast‐decay scintillator, such as LYSO:Ce (Lu2−xYxSiO5:Ce), it exploits the potential of the NUV light‐emitting scintillators. The indirect arrangement of the detector makes it suitable for high‐dose applications that require high‐energy illumination. This allows for synchrotron single‐bunch hard X‐ray imaging to be performed with improved true spatial resolution, as herein exemplified through pulsed wire explosion and superheated near‐nozzle gasoline injection experiments at a pixel size of 3.2 µm, acquisition rates up to 1.4 MHz and effective exposure time down to 60 ps. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate all studies which used the micronucleus assay using oral cells in the attempt to understand whether such technique is efficient in evaluating genotoxicity in gas station attendants. Full manuscripts from 16 studies were carefully selected by the authors. Our results demonstrate that continuous exposure to derivatives of petroleum may lead to genotoxic effects since all studies demonstrated positive findings (16 out of 16) and 11 of them had a strong or moderate final rating. In summary, our results reveal that gas station attendants are occupationally exposed to genotoxic agents and that the micronucleus assay in oral mucosa is indeed an effective method to evaluate genotoxicity in this specific case. Such findings are very important for protecting these professionals who are continuously exposed to chemicals for long periods. [ABSTRACT FROM AUTHOR]

Among surface fabrication methods, electrodeposition is considered the most advantageous because it can be performed using a low-cost fabrication process and generate robust chemical and mechanical Nano films within a short time. This study demonstrates the innovative development and exact optimization of an advanced electrochemical sensor platform designed for the highly sensitive detection and quantification of Phenol present in industrial wastewaters. The sensor's construction entails the meticulous electrodeposition of Nanofilms comprising carboxymethylcellulose (CMC) and Bathocuproine disulfonic acid disodium salt onto a pencil graphite electrode, complemented by the integration of highly efficacious surface modifiers such as carboxymethyl cellulose and Bathocuproine. To unravel the morphology of the fabricated sensor film's nanostructures, scanning electron microscopy (SEM) analysis was employed, affirming the successful electrodeposition. The proposed sensor showed exceptional catalytic activity in the electrooxidation of Phenol, characterized by an impressive α value of 0.93, a substantially high logarithm of Ks of 2.93, and a commendable Γ value of 1.16 × 10–8. A wide standard calibration curve covering a concentration range of 25–225 nmol l−1 was implemented, thus enabling precise and accurate quantification of Phenol. Impressively, the sensor exhibited remarkable sensitivity, evident through its remarkably low limits of detection (LOD) and quantification (LOQ), measuring at 8.31 and 24.97 nmol l−1, respectively. With its exceptional performance, minimal environmental impact, and unparalleled accuracy, this electrochemical sensor exhibited immense potential in the meticulous analysis of Phenol encountered in petrol and resin factory wastewaters. By embracing this state-of-the-art technology in analytical applications, researchers can effectively monitor and develop robust mitigation strategies aimed at combating Phenol contamination. [ABSTRACT FROM AUTHOR]

This paper focuses on the joint optimization of the charging station location problem (CSLP) and discrete network design problem (DNDP) in a transportation network. We present a variational inequality (VI) formulation to describe the user equilibrium (UE) state of gasoline vehicles (GVs) and electric vehicles (EVs). Based on the mixed-UE model, a mathematical program with equilibrium constraints (MPEC) model is formulated for integrating the decisions of deploying EV charging stations (EVCSs) and adding new links to minimize the total travel cost (TTC) of all vehicles. A modified genetic algorithm is developed to tackle the MPEC model with an adaptive path generation procedure to address the mixed-UE model. Finally, we conduct numerical experiments to identify the efficacy of the proposed models and algorithms. Specifically, we propose a two-step optimization model and explore a performance comparison between the joint and two-step optimization approaches, while the joint optimization exhibits superiority in minimizing the TTC. [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]

Low-temperature gasoline combustion (LTGC) with additive-mixing fuel injection (AMFI) is a new combustion strategy that has been demonstrated to deliver 9%–25% better brake thermal efficiency than similar-sized market-leading diesel engines over the operating map. Moreover, the LTGC-AMFI engine shows near-zero smoke, and NOx emissions are 4–100 times lower than those of a diesel, sufficiently low that no aftertreatment, or only passive NOx aftertreatment, would be sufficient (diesel exhaust fluid is not required). LTGC-AMFI combustion is based on kinetically controlled compression ignition of a dilute charge with a variable amount of low-to-moderate fuel stratification. Fast combustion control is provided by adding minute amounts of an ignition-enhancing additive into the fuel each engine cycle to control its reactivity. This strategy was used to operate a medium-duty (MD) LTGC-AMFI engine at loads from idle to 16.3 bar BMEP and speeds from 600 to 2400 rpm with regular E10 gasoline, which covers nearly the entire operating map of a typical MD engine. Turbine-out temperatures were sufficient for an oxidation catalyst to control hydrocarbon and CO emissions. Autonomie simulations over the GEM ARB Transient and the GEM 55 mph Cruise driving cycles for class-6 trucks using this technology showed fuel economies of 8.1 and 11.4 mpg-gasoline-equivalent, respectively, corresponding to 18.6% and 13.4% improvements over a similar-size diesel engine. Engine-out NOx emissions were 0.024 and 0.01 g/bhp-h, respectively, well below current U.S. emission standards. These results show that switching from diesel to LTGC-AMFI engines would greatly reduce greenhouse gas (GHG) emissions for off-road, MD and HD applications, which will continue to rely on combustion engines because electrification is not practical in the foreseeable future. With their reduced fuel consumption, the lower cost of gasoline compared to diesel fuel, and much lower aftertreatment costs, LTGC-AMFI engines also offer a significantly lower total cost of ownership. [ABSTRACT FROM AUTHOR]

Adopting zero-carbon fuels, like hydrogen, can significantly reduce environmental harm and pave the way for a decarbonised trajectory with zero carbon emissions. The hydrogen internal combustion engine (ICE) technology has demonstrated its reliability and capacity to seamlessly integrate into the current ICE platform, originally designed for diesel and gasoline operation. The direct utilisation of pure hydrogen eradicates steady-state carbon dioxide and hydrocarbon emissions. It is important to highlight that efforts to comprehend and comprehensively tackle NOx emissions are underway. A comprehensive study was carried out to assess the NOx emissions for a hydrogen ICE with different injection modes from gasoline. The study involved varying the relative air-to-fuel ratio (AFR) from stoichiometric to the lean-burn limit in a boosted spark ignition (SI) engine fuelled with gasoline or hydrogen. A fast NOx emissions analyser was employed to measure the instantaneous NO and NO2 emissions in the engine exhaust. The study provides a detailed analysis of NOx emissions, including steady-state averaged emissions, average crank angle domain NOx distribution and emissions, in-cylinder pressure analysis, as well as time and cycle analyses of NOx emissions' temporal and cyclic variations. The primary discovery was that NOx emissions are almost zero between lambda 2.75 and 3.7, and hydrogen produces 13.8% less NOx emissions than gasoline at stoichiometric operation. Finally, the full NOx time analysis revealed that the consistency of NOx emissions is higher with hydrogen than with gasoline by using a novel approach by identifying the coefficient of variation of the NOx emission of each cycle. [ABSTRACT FROM AUTHOR]

Although the direct conversion of syngas to gasoline fuel offers a promising route to produce liquid fuel from non-petroleum carbon resources, it remains a great challenge owing to low target product selectivity and poor catalyst stability. Hence, we designed a bifunctional catalyst consisting of SiO2-coated novel hierarchical porous cage active particles and hierarchical porous zeolite, which provided a C5–C11 hydrocarbon selectivity of 63.5 wt%, and the yield reached 99.3% in C5+ hydrocarbons, with an aromatic content of 25.7% at 280 °C. Particularly, this value is within the range of the restricted aromatic content. As the reaction temperature was elevated to 310 °C, zeolite-24 presented an excellent aromatic selectivity of 64.4% in liquid hydrocarbons. This is mainly because the zeolite provides higher acidity at a rather high reaction temperature, facilitating the formation of hydrocarbons in the liquid phase, which were predominantly aromatics rather than i-C5+. Besides aromatics, a high i-C5+ content of 77.4% in liquid hydrocarbons was obtained at 280 °C over FeZ-16. At the given condition, the synthesized hybrid catalysts were beneficial for the production of gasoline fuels consisting of aromatics and i-C5+. Particularly, 280 °C offered optimum selectivity to i-C5+, and 310 °C was suitable for the formation of aromatics. This work provides a strategy for the design and preparation of novel and efficient catalysts for gasoline production. [ABSTRACT FROM AUTHOR]

Ethanol fuel is considered a renewable energy source with a lower global warming potential than gasoline. The purpose of this paper is to analyze the emissions and performance of gasoline-ethanol blends in SI engines under various conditions. A computerized 4s, 1cyl, VCR spark ignition engine is used for the tests to measure the performance of Gasoline-Ethanol (GE) blends in particular E-10 (10% ethanol, 90% gasoline). For measuring exhaust emissions as well as performance, regular gasoline fuel is used for the additional tests. Engine performance using ethanol-gasoline blended fuel has been evaluated at different working conditions: 1200-1800 rpm, AFR 0.9, STs 300, CR10:1. When vehicles running on ethanol-gasoline blend indicated a decrease in the amounts of HC, NOx, and CO exhaust gases while 3.9% increase in CO2 emissions as compared to unleaded gasoline fuel. Furthermore, it has been shown that the brake power, torque, specific fuel consumption increases when a Gasoline-Ethanol (GE) blend is used over regular gasoline fuel. [ABSTRACT FROM AUTHOR]

This paper mainly reviews the research status of PV technology in the separation of organic mixtures in recent years. The main research achievements of PV technology in the separation of polar/non-polar mixture, aromatic/alkane, isomeric, and removal of sulfide in gasoline are described in detail. At the same time, we look forward to the development direction of PV technology in the field of separating organic mixtures and provide a reference for the subsequent research on the separation of organic mixtures by PV technology. [ABSTRACT FROM AUTHOR]

Environmental exposures impact amyotrophic lateral sclerosis (ALS) risk and progression, a fatal and progressive neurodegenerative disease. Better characterization of these exposures is needed to decrease disease burden. To identify exposures in the residential setting that associate with ALS risk, survival, and onset segment. ALS and control participants recruited from University of Michigan completed a survey that ascertained exposure risks in the residential setting. ALS risk was assessed using logistic regression models followed by latent profile analysis to consider exposure profiles. A case-only analysis considered the contribution of the residential exposure variables via a Cox proportional hazards model for survival outcomes and multinomial logistic regression for onset segment, a polytomous outcome. This study included 367 ALS and 255 control participants. Twelve residential variables were associated with ALS risk after correcting for multiple comparison testing, with storage in an attached garage of chemical products including gasoline or kerosene (odds ratio (OR) = 1.14, padjusted < 0.001), gasoline-powered equipment (OR = 1.16, padjusted < 0.001), and lawn care products (OR = 1.15, padjusted < 0.001) representing the top three risk factors sorted by padjusted. Latent profile analysis indicated that storage of these chemical products in both attached and detached garages increased ALS risk. Although residential variables were not associated with poorer ALS survival following multiple testing corrections, storing pesticides, lawn care products, and woodworking supplies in the home were associated with shorter ALS survival using nominal p values. No exposures were associated with ALS onset segment. Residential exposures may be important modifiable components of the ALS susceptibility and prognosis exposome. [ABSTRACT FROM AUTHOR]

When compared to other internal combustion engine types (SI engine, CI engine), the gasoline compression ignition engine (GCI engine) offers a promising and efficient way to enhance heat efficiency and less harmful emissions. The development of new engine technologies is aimed at optimizing the performance of GCI engines by allowing them to operate more efficiently at part load and using lower octane gasoline fuel under higher compression ratios. The GCI engine struggles to cope with a large amount of smoke, soot, HC and CO, and it is not very stable when operating at a low load or when it is exposed to high load conditions, which can cause autoignition. This study will introduce certain technologies, such the strategy for dealing with exhaust gas recirculation (EGR) and oxygen content, that assist in resolving the issues faced by the GCI engine. The research results show that the ignition delay tends to decrease with an increase in EGR. The ignition delay reaches its minimum value at 20% EGR with GB05 fuel. The maximum pressure in the combustion chamber of a GB05-fueled engine can be improved at 20% EGR. The engine's thermal efficiency and NOx emissions decrease, while CO and HC emissions increase with increasing EGR. The increase in oxygen content led to a decrease in ignition delay and lift-off length. [ABSTRACT FROM AUTHOR]

This study introduces a simple, cost-effective, and rapid bismuth electrode-square-wave voltammetry method for determining the total sulfur content in automotive gasoline. Optimal conditions for the developed electrode, including various Bi ion concentrations, deposition times, and potentials, were established on a glassy carbon electrode. The results demonstrated that the highest response was achieved when the bismuth electrode was placed in an acetate buffer and a methanol:toluene (1:1 v/v) solvent. The method was validated with and without a 30-second electro-preconcentration step. The voltammetric method in conjunction with the preconcentration step exhibited a sensitivity of 571.81 nA mg L−1, a limit of detection (LOD) of 0.02 mg L−1, and a limit of quantification (LOQ) of 0.08 mg L−1. Without the preconcentration step, the method yielded a sensitivity of 421.89 nA mg L−1, an LOD of 0.03 mg L−1, and an LOQ of 0.11 mg L−1. The developed method was applied to quantify commercial fuel samples. The results showed that the electrochemical technique yielded a similar total sulfur content to that measured by the standard ASTM D2622 method, with an error of less than 7.5%. Moreover, the method proposed in this study had lower LOD and LOQ limits, meeting the EURO5 and EURO6 regulations. [ABSTRACT FROM AUTHOR]

End-gas auto-ignition leading to knocking combustion is one of the major barriers to achieving higher thermal efficiencies in downsized boosted spark-ignition engines. Despite the available framework addressing hotspot-induced ignition (detonation peninsula), a quantitative investigation on hotspot-induced auto-ignition of gasoline surrogates is yet to be done. In particular, the effect of negative temperature coefficient (NTC) chemistry on the distribution of the ignition modes in the detonation peninsula is still missing. Using the established one-dimensional (1D) theoretical and computational framework, the effect of average temperature (including NTC range), initial pressure, and ethanol addition are investigated. Moreover, appearance of NTC chemistry-related events i.e. coolspots, secondary ignition kernels, and off-centered ignition are analyzed using 1D simulations. The results are as follows. 1) NTC chemistry affects the distribution of ignition regimes in detonation peninsula and the dynamics of the front propagation via altering the reactivity gradient. 2) NTC chemistry increases the temperature gradient range associated with the detonation regime. 3) NTC may inhibit detonation development by simultaneously promoting the spontaneous/supersonic ignition modes. 4) An ethanol blend decreases the knock propensity; however, lower ignitability may promote detonation development and the appearance of strong shock waves. 5) Finally, detonation may result in a normal knock at lower initial pressures (20 bar). However, at elevated initial pressures (50 bar), detonation is noted to yield pressure intensities resembling super-knock. [ABSTRACT FROM AUTHOR]

PT Kilang Pertamina International (KPI), as a subsidiary of PT Pertamina (Persero), currently operates and fully administers the refinery business subholding, intends to build new Gasoline Sulfur Hydrotreater (GSH) unit to comply with the latest government regulation for Sulphur content of Gasoline shall be adjusted maximum 50 ppm by the end of 2027. In doing the project execution, it is important to find and decide the optimum Project Delivery Method (PDM) that shall be used effectively for GSH Project at the Plaju and Balongan Refineries to achieved PT KPI ultimate goal which is OTOBOSOR (On Time, On Budget, On Specification, On Regulation). The purpose of this study is to determine the selection of the optimal project delivery method for the Petroleum Sulfur Hydrotreating project at the Plaju and Balongan Refineries of PT Kilang Pertamina International (KPI). In this study, qualitative data will be used in the analysis to provide more opportunities and space for gaining a deeper understanding of a certain subject, allowing for flexibility and exploration. Those parameters are analyzed through Pair Wise Comparation Analysis of AHP Model. Based on the analysis, the best alternative to be implemented is Co-Current DBB. In terms of sensitivity analysis, Co-Current DBB is also robust and gives a solid highest value compared with the other alternatives. Therefore, Co-Current DBB is a suitable scheme to be implemented for accelerating Project step from design bidding process until EPC Phase of GSH Project. [ABSTRACT FROM AUTHOR]

Accurate energy consumption prediction is crucial for addressing energy scheduling problems. Traditional machine learning models often struggle with small-scale datasets and nonlinear data patterns. To address these challenges, this paper proposes a hybrid grey model based on stacked LSTM layers. This approach leverages neural network structures to enhance feature learning and harnesses the strengths of grey models in handling small-scale data. The model is trained using the Adam algorithm with parameter optimization facilitated by the grid search algorithm. We use the latest annual data on coal, electricity, and gasoline consumption in Henan Province as the application background. The model's performance is evaluated against nine machine learning models and fifteen grey models based on four performance metrics. Our results show that the proposed model achieves the smallest prediction errors across all four metrics (RMSE, MAE, MAPE, TIC, U1, U2) compared with other 15 grey system models and 9 machine learning models during the testing phase, indicating higher prediction accuracy and stronger generalization performance. Additionally, the study investigates the impact of different LSTM layers on the model's prediction performance, concluding that while increasing the number of layers initially improves prediction performance, too many layers lead to overfitting. [ABSTRACT FROM AUTHOR]

The quality of fuel depends on its chemical composition, which influences engine performance. Gas chromatography, a cornerstone of global oil and fuel R&D, remains crucial for ensuring the quality of petroleum products and regulatory compliance. Scientists use the most accurate analysis (PIONA) as a tool derived from gas chromatography coupled with mass spectrometry to identify and quantify hydrocarbons that influence resistance to detonation, which is determined by the research octane number (RON). This study introduces the "average carbon number (ACN)", calculated from the molar chemical composition of commercial gasoline samples sold in Ecuador (Extra gasoline and Súper gasoline). A quantitative comparison of the ACN with techniques applied using standardized international procedures reveals that the ACN characterizes gasoline samples by providing insight into the distribution shape of carbon graphs. A comprehensive statistical analysis demonstrates the potential usefulness of ACN in characterizing fuel composition, highlighting its relevance in broader fuel quality assessments without the need for carbon distribution plots. [ABSTRACT FROM AUTHOR]

The extent to which emission control technologies and policies have reduced anthropogenic NOx emissions from motor vehicles is large but uncertain. We evaluate a fuel-based emission inventory for southern California during the June 2021 period, coinciding with the Re-Evaluating the Chemistry of Air Pollutants in CAlifornia (RECAP-CA) field campaign. A modified version of the Fuel-based Inventory of Vehicle Emissions (FIVE) is presented, incorporating 1.3 km resolution gridding and a new light-/medium-duty diesel vehicle category. NOx concentrations and weekday-weekend differences were predicted using the WRF-Chem model and evaluated using satellite and aircraft observations. Model performance was similar on weekdays and weekends, indicating appropriate day-of-week scaling of NOx emissions and a reasonable distribution of emissions by sector. Large observed weekend decreases in NOx are mainly due to changes in on-road vehicle emissions. The inventory presented in this study suggests that on-road vehicles were responsible for 55-72% of the NOx emissions in the South Coast Air Basin, compared to the corresponding fraction (43%) in the planning inventory from the South Coast Air Quality Management District. This fuel-based inventory suggests on-road NOx emissions that are 1.5 ± 0.4, 2.8 ± 0.6, and 1.3 ± 0.7 times the reference EMFAC model estimates for on-road gasoline, light- and medium-duty diesel, and heavy-duty diesel, respectively.

Abstract Crude oil is made up of very complex compounds, which are found in polar organic substances especially organic acid compounds in the majority. Although organic acid content in crude oil is low, the presence of organic acids affects the interfacial tension (IFT) in oil reservoirs thereby altering the enhancement of oil recovery using nitrogen gas (N2) injection. Therefore, in this study, the effects of pressure (1 to 35 bar), the percentage of aromatic compounds (0.0 to 100 vol%) in the aliphatic hydrocarbon samples and the organic acid (benzoic acid) content (0.0 to 0.8 g.L− 1) on IFT between a mixture of gasoline/diesel fuel and N2 were investigated at a temperature of 298 K. IFT does not necessarily decrease as pressure increases for the sake of existence of aromatic compounds. IFT alteration for gasoline was more (about 8 dyne.cm− 1) than for diesel fuel (approximately 4 dyne.cm− 1) during pressure increased from 1 to 35 bar due to the replacement of heavy long chain aliphatic compounds instead of light aromatic matters. The effect of IFT alteration between N2 and diesel fuel during increasing the organic acid content was little (approximately 1.5 dyne.cm− 1), in contrast, this effect was more noticeable for N2/gasoline (about 8 dyne.cm− 1). In addition, a reduced cubic model for estimating IFT between N2 and petroleum fractions in terms of pressure, petroleum fraction composition and organic acid content was proposed with an average relative error of less than 2.6%.

Gasoline fuel is a kind of fossil fuel that is still the primary fuel for vehicles and motorcycles nowadays. Demand for fuel continues to increase from time to time, so an effort is needed to save the use of fuel. This research is intended as an initial study to determine the quantity of heat energy converted and distributed into several engine performance parameters. Furthermore, the results of this study became the basis for the development of similar research to produce high engine performance and low emissions as well as economists by setting combustion parameters. The result shows that only a small portion of the heat generated from pertalite fuel is used as effective power. Most of the heat energy from the fuel is wasted in the environment and distributed into radiant heat, and some of it becomes heat to the exhaust gases and heat to the cooling water.

This novel research presents an investigation on petroleum products dehydration using the adsorption method by low-cost adsorbents. To investigate the performance of proposed process intended to separate emulsified water, synthetic stabilized water emulsions in different petroleum products (Gasoline, Kerosene, and Gas oil) which equal 300, 600, and 800 ppm were prepared. Afterwards, under batch conditions, natural zeolite and activated carbon as economic adsorbents were utilized for the dehydration process. The characteristics of adsorbent was examined using SEM and XRD analysis. The obtained results from BET analysis also depicted that the specific surface area of activated carbon was considerably more than that of zeolite. Results showed that both zeolites and activated carbon can effectively purify petroleum products from undesirable emulsified water. The comparison of the adsorbents' efficiency indicated that activated carbon has a higher affinity than zeolite for water in gasoline and gas oil, however, they had almost the same adsorption capacity in kerosene dehydration. The maximum water removal percentage of gas oil, kerosene and gasoline using zeolite was 84.84, 92.17, and 88.64, respectively. Dehydration by activated carbon also led to 86.44, 93.43 and 90.2 per cent water removal from gas oil, kerosene and gasoline, respectively. [ABSTRACT FROM AUTHOR]

The global practice of blending bioethanol with petroleum fuels serves the dual purpose of reducing fuel costs and mitigating vehicular emissions. However, variations from the stipulated amount of bioethanol in petroleum fuels can be detrimental to engine longevity and performance. Notably, portable analytical devices capable of swiftly and accurately assessing fuel samples without necessitating prior pretreatment have been developed by researchers. This review aims to elucidate the advances and prevailing trends in analytical tools such as electrochemical, spectroscopic, electrical, optical fiber-based, and physical parameter-based techniques for the determination of blended fuel composition. [ABSTRACT FROM AUTHOR]

The aim of the research is to determine changes in the composition of selected gasoline compounds in cotton carpet samples due to different weathering times. EVO 95 gasoline was used as a fire accelerant and a cotton carpet was used as a matrix. The samples were exposed to various weathering durations (0–360 min) in laboratory conditions. We investigated samples that were unburnt (only weathered) and samples that were burned and subsequently subjected to further weathering. Residual gasoline compounds in carpet samples were determined by gas phase extraction (headspace – HS) coupled with gas chromatography (GC) and mass spectrometry (MS). We focused on the comparison of selected gasoline compounds; toluene, ethylbenzene, p-xylene, 1,2,3-trimethylbenzene (TMB), 1,3,5-trimethylbenzene and naphthalene. The biggest changes were determined in the reduction of the intensity of most volatile compounds (alkylalkanes), where toluene decreased by 11.92%. A similar but not so pronounced trend, occurred in the burned samples, where toluene decreased by 7.40%. Minor changes occurred in alkyl derivatives of benzene, where some of the total 15 gasoline markers also occur, e.g. (1,2,3-trimethylbenzene, 1,3,5-trimethylbenzene). On the contrary, naphthalene as a heavier compound showed an increase in intensity about 0.42%. For burnt samples, the increase was 1.31%. The results show that largest changes can be observed after four or five hours of weathering, which implies the need for rapid sampling and subsequent timely analysis. [ABSTRACT FROM AUTHOR]