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The aim of this paper is to present mathematical models of all the propulsion components of hybrid drivetrains. These models are based on very limited amounts of data, nevertheless they match real characteristics with high accuracy based on numerous measurement data points, thus they allow the modelling process of fuel and energy consumption for a particular vehicle in any homologation driving cycle to be performed in a very short time at the early stage of vehicle design. The characteristics provided in the article concern: the full load engine torque curve, full load electric motor power curve, combustion engine efficiency characteristic, including dynamic states and warm-up period, electric motor efficiency characteristic, inverter efficiency characteristic, battery characteristics in a wide temperature range and efficiency of the drivetrain. Moreover, the main principles concerning gear ratio selection are provided to conduct subsequent steps of transmission modelling from scratch. Simulations of drivetrain performance and vehicle fuel consumption in WLTP and US06 tests prove the suitability of the presented models. [ABSTRACT FROM AUTHOR]

With the transition from the German national emissions trading system to the European Emissions Trading System (EU ETS2) from 2027, final consumer prices for fossil motor and heating fuels are likely to rise significantly. This increase will affect low-income households more noticeably, as they spend a larger share of their income on energy than high-income households. Existing relief measures, such as the basic income scheme, the housing benefit, and subsidy programs, only partially reach these groups. A climate dividend that is automatically paid out to all residents largely mitigates excessive effects of the carbon pricing burden. However, additional aid and subsidy programs are required due to the remaining burdens on vulnerable low-income households with high energy consumption. These programs could be financed if above-average and high-income earners did not receive the climate dividend. Carbon pricing does not affect these groups as much and they generally have more opportunities to reduce their fossil energy consumption. Thus, the climate dividend should be paid to all households, but reduced unbureaucratically as a part of wage and income taxes for above-average and high-income earners. [ABSTRACT FROM AUTHOR]

Oil refining is a branch of industry that delivers energy to move our vehicles. The transportation of people and goods by airplanes, ships, trains, trucks, buses, and cars is unthinkable for modern mankind without the use of refined petroleum automotive fuels. Thus, the optimal functioning of this industrial branch is vital to contemporary human society. The modeling of processes that take place during refined oil products' manufacturing, which are parallel in their essence, by generalized nets enables their activity optimization and better management. The generalized nets, which are in principle extensions of Petri nets, are applied in this research as a toolkit to model all processes from crude oil selection and delivery to a high complex refinery (Nelson index of 10.6) to the production of a great diversity of fuels, propylene, and polypropylene. The proposed article is a continuation and extension of the articles, published in Mathematics Journal in 2021 and 2023. It is the first (theoretical part) of our comprehensive study of modeling petroleum products' production processes in a refinery, and the second part will discuss the results of the software implementation of the model. [ABSTRACT FROM AUTHOR]

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Traditional automotive proton exchange membrane fuel cell (PEMFC) endurance testing relies on the fuel cell (FC) dynamic load cycle (FC‐DLC) protocol, which inadequately reflects real‐world driving conditions. To address this limitation the "Investigations on degradation mechanisms and Definition of protocols for PEM Fuel cells Accelerated Stress Testing" (ID‐FAST) consortium defined the new representative "ID‐FAST driving load cycle," a novel approach capturing the load distribution, transitions, temperature variations, and humidity fluctuations experienced by FCs in real‐world operation. We demonstrate the ID‐FAST driving cycle itself and the integration into a realistic durability test program for FC test benches and present the resulting test data. Furthermore, we showcase its implementation within an accelerated stress testing (AST) protocol, highlighting its potential to significantly reduce testing time by accelerating degradation. Additionally, a novel method for highly dynamic humidity adjustment within test benches is introduced. By overcoming limitations of existing methods and incorporating the ID‐FAST driving cycle, this work paves the way for a new era of efficient and realistic FC endurance testing, ultimately contributing to the development of more robust and durable automotive FC stacks. [ABSTRACT FROM AUTHOR]

New bifunctional composite catalysts for the Fischer—Tropsch synthesis were developed on the basis of a mixture of the Co—Al2O3/SiO2 catalyst, meso-HZSM-5 hierarchical mesoporous zeolite, and boehmite binder. The mesoporous zeolite was obtained by alkaline treatment of the industrial HZSM-5 zeolite. The developed catalysts are suitable for one-pot conversion of syngas into linear C5+ hydrocarbons, which then undergo cracking and isomerization reactions. The effect of the concentration of NaOH solution on the porosity and catalytic efficiency of the obtained meso-HZSM-5 zeolite was studied. The performances of the bifunctional catalysts obtained from alkali-treated and pristine HZSM-5 in the conversion of syngas were compared. In the presence of the catalyst based on the alkali-treated zeolite, the total productivity to C5+ hydrocarbons somewhat decreases. However, the increase in the total yield of branched and unsaturated hydrocarbons provides the formation of motor fuels with high anti-knock properties. [ABSTRACT FROM AUTHOR]

A one-dimensional computational model has been developed that can be used to identify operating conditions for the cathode side of a proton exchange membrane fuel cell such that both the inlet and outlet relative humidity is equal to 100%. By balancing the calculated pressure drop along the cathode side flow channel with the change in molar composition, inlet conditions for the cathode side can be identified with the goal of avoiding channel flooding. The channel length, height, width and the land-to-channel width ratio are input parameters for the model so that it might be used to dimension the cathode flow field. The model can be used to calculate the limiting current density, and we are presenting unprecedented high values as a result of the high pressure drop along the flow channels. Such high current densities can ultimately result in a fuel cell power density beyond the typical value of 1.0–2.0 W/cm2 for automotive fuel cells. [ABSTRACT FROM AUTHOR]

Petroleum refining has been, is still, and is expected to remain in the next decades the main source of energy required to drive transport for mankind. The demand for automotive and aviation fuels has urged refiners to search for ways to extract more light oil products per barrel of crude oil. The heavy oil conversion processes of ebullated bed vacuum residue hydrocracking (EBVRHC) and fluid catalytic cracking (FCC) can assist refiners in their aim to produce more transportation fuels and feeds for petrochemistry from a ton of petroleum. However, a good understanding of the roles of feed quality and catalyst characteristics is needed to optimize the performance of both heavy oil conversion processes. Three knowledge discovery database techniques—intercriteria and regression analyses, and artificial neural networks—were used to evaluate the performance of commercial FCC and EBVRHC in processing 19 different heavy oils. Seven diverse FCC catalysts were assessed using a cascade and parallel fresh catalyst addition system in an EBVRHC unit. It was found that the vacuum residue conversion in the EBVRHC depended on feed reactivity, which, calculated on the basis of pilot plant tests, varied by 16.4%; the content of vacuum residue (VR) in the mixed EBVRHC unit feed (each 10% fluctuation in VR content leads to an alteration in VR conversion of 1.6%); the reaction temperature (a 1 °C deviation in reaction temperature is associated with a 0.8% shift in VR conversion); and the liquid hourly space velocity (0.01 h-1 change of LHSV leads to 0.85% conversion alteration). The vacuum gas oil conversion in the FCC unit was determined to correlate with feed crackability, which, calculated on the basis of pilot plant tests, varied by 8.2%, and the catalyst ΔCoke (each 0.03% ΔCoke increase reduces FCC conversion by 1%), which was unveiled to depend on FCC feed density and equilibrium FCC micro-activity. The developed correlations can be used to optimize the performance of FCC and EBVRHC units by selecting the appropriate feed slate and catalyst. [ABSTRACT FROM AUTHOR]

In this study, we propose a random cropping augmentation (RCA) based on an optimized YOLOv8 algorithm by introducing a tiny object detection layer to improve the accuracy of surface defect detection on the inner wall of micro-holes of cylindrical high-precision parts. The inner surfaces of cylindrical high-precision parts possess attributes like high smoothness, elongated channels, limited visibility, minute flaws, and challenges capturing image data. These characters impose significant difficulties in automating defect detection for this part type. Taking the automobile fuel injector valve seat as an example, industrial CCD cameras and lenses are combined with a circular light source to acquire magnified image data. The images are preprocessed using tile and adaptive histogram equalization algorithms. Then, the RCA algorithm expands and randomly combines the image data. We compare the proposed algorithm with the original faster RCNN, YOLOv5 and YOLOv8 algorithm for surface defect detection on the inner wall of the automotive fuel injector valve seat. The experimental results demonstrate that after extending the dataset with the RCA algorithm, there have been significant improvements in the mean average precision (mAP) for the faster RCNN, YOLOv5, and YOLOv8 algorithms. The mAP@0.5 for these algorithms has increased from 37.1%, 48.7%, and 62.2% to 60.9%, 72.6%, and 81.1%, respectively. Furthermore, the improved YOLOv8 algorithm, which incorporates tiny object detection module, achieved an mAP@0.5 of 87% on the dataset extended by the RCA algorithm, with precision and recall reaching 89.7% and 80.6%, respectively. The improved YOLOv8 + RCA algorithm performs better than mainstream algorithms in surface defect detection on the inner wall of the fuel injector valve seat while meeting the requirements of industrial production quality inspection for detection speed. [ABSTRACT FROM AUTHOR]

With the aim of enhance the designability of burning surface, star and wagon wheel fuel types are applied extensively in hybrid rocket motors. However, mechanism of nozzle ablation in hybrid rocket motors with these complex fuel types is unclear, and this increases the difficulty of predicting ablation laws and thrust. This paper intends to investigate spatial distribution characteristics of nozzle ablation in the hybrid rocket motor with various fuel types. According to the principle that the grain port area and grain length are equal, tube, star, single-port wagon wheel, and multi-port wagon wheel grains are designed. Numerical models for combustion flow and thermochemical erosion are established, and three-dimensional numerical simulations are conducted. A firing test for nozzle erosion is conducted, and hydroxyl-terminated polybutadiene and 95 % hydrogen peroxide are employed. Errors of throat erosion rate and combustion chamber pressure among simulation results and experimental data are 4 % and 4.25 %, respectively. Calculation results demonstrate that the circumferential distributions of nozzle wall temperature and erosion rate show an obvious correlation with fuel types. The maximum throat erosion rates for star, single-port wagon wheel, and multi-port wagon wheel grains occur at the circumferential position of 0° (star slot, spoke slot, and midpoint of outer edge of wheel hole), while the minimum throat erosion rates locate at the circumferential position of 36° (star root, spoke root, and midline of adjacent wheel holes). The circumferential non-uniformity of throat erosion rate of multi-port wagon wheel grain is the highest. When the grain port area and oxidizer mass flow rate are the same, the throat erosion rate of multi-port wagon wheel grain is the highest, followed by the star grain, and the throat erosion rate of single-port wagon wheel grain is the lowest. • Effect of complex fuel types on spatial characteristics of nozzle erosion is studied. • Firing test of carbon-based nozzle erosion is performed to verify numerical models. • Three-dimensional simulations on erosion in hybrid rocket motors are conducted. • Simulation results agree well with test data. • Ablation mechanism of star, single-port, and multi-port wagon wheel grain is revealed. [ABSTRACT FROM AUTHOR]

This research considers different storable oxidizer and fuel combinations for hybrid propulsion, looking for the most adequate candidates for mass and volume limited systems. High specific impulse Isp is the main indication for minimum mass, whereas high density specific impulse ρIsp is a good measure for smaller volume. Other aspects such as safety, handling, toxicity, burn rate, hypergolicity, and the oxidizer to fuel O/F ratio, may affect the final choice of propellant ingredient combination. For mass‐limited systems hydrogen peroxide H2O2 or nitrogen tetroxide N2O4 (the latter is toxic and hard to handle) oxidizers give the best results with most solid fuels (mainly hydroxyl‐terminated polybutadiene HTPB). For volume‐limited systems the same combinations may apply; however, in that case polyester fuel may be an adequate choice as well because of its high density. Nitrous oxide N2O is the most inadequate oxidizer for volume‐limited systems, yielding ρIsp lower by about 40 % compared to other oxidizers. Reducing the structure and insulation mass may result from decreasing the high‐pressure, high‐temperature section (the combustion chamber) and can be achieved from high O/F combinations employing N2O or H2O2 oxidizers. N2O gives relatively safe system, H2O2 enables hypergolic combinations, HNO3 is good for long‐term storage, whereas paraffin wax and expandable graphite additive yield high fuel regression rate and thrust. Overall, H2O2 oxidizer seems optimal for many operational aspects, but it should be chemically stabilized to minimize decomposition. [ABSTRACT FROM AUTHOR]

Adulteration of diesel fuel poses a major concern in most developing countries including Ghana despite the many regulatory schemes adopted. The solvent tracer analysis approach currently used in Ghana has over the years suffered several limitations which affect the overall implementation of the scheme. There is therefore a need for alternative or supplementary tools to help detect adulteration of automotive fuel. Herein we describe a two-level classification method that combines NMR spectroscopy and machine learning algorithms to detect adulteration in diesel fuel. The training sets used in training the machine learning algorithms contained 20–40% w/w adulterant, a level typically found in Ghana. At the first level, a classification model is built to classify diesel samples as neat or adulterated. Adulterated samples are passed on to the second stage where a second classification model identifies the type of adulterant (kerosene, naphtha, or premix) present. Samples were analyzed by 1H NMR spectroscopy and the data obtained were used to build and validate support vector machine (SVM) classification models at both levels. At level 1, the SVM model classified all 200 samples with only 2.5% classification errors after validation. The level 2 classification model developed had no classification errors for kerosene and premix in diesel. However, 2.5% classification error was recorded for samples adulterated with naphtha. Despite the great performance of the proposed schemes, it showed significantly erratic predictions with adulterant levels below 20% w/w as the training sets for both models contained adulterants above 20% w/w. The proposed method, nevertheless, proved to be a potential tool that could serve as an alternative to the marking system in Ghana for the fast detection of adulterants in diesel. [ABSTRACT FROM AUTHOR]

This article presents the results of engine and laboratory tests with fuel before and after treatment with a heavy particle generator. The results of the research have shown that in the course of conducted research the impact of heavy particle generator on fuel during engine tests leads to an increase in its detonation resistance and a reduction in fuel consumption (up to 15%), as well as significantly improves the environmental performance of the engine. The reduction in concentration of carbon monoxide (CO) from 0.09% to 0.03%, carbon dioxide - by 6% and nitrogen oxides - by 7%. The results of research of hydrocarbon composition of fuels by GC-MS method have shown that the impact of heavy particles generator have a favorable effect on the octane number of gasoline, as well as low-temperature properties of diesel fuel. The change of engine operation parameters after the impact of heavy particles generator is established. The change can occur as a result of complex influence on fuel and engine systems, and as a result of influence on a single factor, which is the root cause of the subsequent change of parameters. [ABSTRACT FROM AUTHOR]

The article considers the possibility of processing oil sludge, a waste product of oil refining, using an energy-efficient technology based on the thermal cracking process. This process takes place at a temperature of 460-470°C and a pressure of 0.11-0.14 MPa. The process produces 57-60 % fuel and 27-34 % oil fractions that can be used in the production of commercial oil products. The industrial implementation of this oil sludge processing technology allows to produce an additional amount of commercial oil products, as well as to solve the problem of accumulation of harmful waste from the oil refining industry, which has a negative impact on the environment. [ABSTRACT FROM AUTHOR]

From Iran and Mozambique to France's Gilets jaunes , consumer energy protests are ubiquitous today. Little historical scholarship has so far explored such "fuel riots," the problematic moniker bestowed by contemporary policy scholars. This article argues for disaggregating the homogenous crowd of so-called rioters, instead analyzing why particular socioeconomic groups persistently take to the streets. To do this, it sketches an energy-centered approach to class with both structural and subjective axes. This analytic is applied to a comparative history of two of the best-documented energy protests of the last half-century. During the 1970s, independent truckers blocked American highways to protest the high price of motor fuel. A decade later, half a million North Indian farmers mobilized to demand cheaper and more reliable electricity. Half a world apart, the two movements shared key characteristics. They were the expression of specific class fractions whose material interests were conditioned by heavy dependence on state-mediated energy supplies. Awkwardly located between big capital and wage labor, both truckers and farmers owned stakes in the carbon-intensive means of production that left them exposed to volatility in energy quality and pricing. Both mobilized in reaction to perceived breaches of state-centered moral economies of energy which threatened this dependence, leveraging their power to interrupt supplies within the circulatory systems of fossil fuel society. Even as both movements failed in their own terms, their political resistance helped to lock in place consumer subsidies for cheap carbon-intensive energy. Such energy protests deserve a central role in our environmental histories of fossil fuel society. [ABSTRACT FROM AUTHOR]

According to international standards, motor fuels require limits on the content of sulfur, benzene, aromatic and olefinic hydrocarbons. Achieving these standards requires the development of new, active, and selective catalysts alongside advancement in technologies for deep hydrotreating and hydroprocessing. Therefore, this study aimed to investigate tetradecane and diesel oil fraction hydroprocessing using modified zeolite-based Ni(Co)-Mo(W)/Al2O3-ZSM-5 catalysts under varying processing conditions. The novelty is attributed to the synthesis of new catalysts based on ZSM-5 type zeolite, modified with metals Ni(Co)-Mo(W) and active additives of rare earth metals and phosphorus. The results showed that after hydrotreating diesel oil fraction on KT-3 catalyst, the pour point and sulfur level decreased from -27 to -57°C and 0.141 to 0.059% respectively, while the yield of the liquid phase was 92.2%. The lowest residual sulfur content (0.005%) was observed on KT-4 catalyst at 400°C. Based on electron microscopic examinations, modified zeolite-based catalysts were distributed in a highly dispersed manner, and the metal components in the active phase were primarily in the oxidized state, generating associate clusters on the surface. The dispersion, structure, and state were influenced by the characteristics of catalyst components. In conclusion, modified zeolite-based catalysts had multifunctional properties, facilitating hydrocracking, hydroisomerization, hydrodesulfurization, and dehydrogenation reactions concurrently. [ABSTRACT FROM AUTHOR]

The article presents the definition of bioindustry, in particular biorefinery. The technology for obtaining synthetic fuel EtG (Ethanol to Gasoline) in a plant using bioethanol from food waste was presented. The physicochemical properties of EtG fuel were presented. EtG fuel stands out due to its limited content of benzene and sulfur and a low content of mechanical impurities and heavy metals. EtG fuel can be considered a replacement fuel for motor gasoline. The results of exhaust emissions tests from vehicles with spark-ignition engines in the WLTC test on a hot and cold engine were presented. It was found that EtG fuel is characterized by lower specific distance emissions of CO, NOx, and CH4 and slightly higher specific distance emissions of NMHC when starting a cold engine compared to gasoline, while the specific distance emission of CO2 for both fuels were very similar. [ABSTRACT FROM AUTHOR]

In this work, a new plastic-intensive medium-pressure plate (MPP), which is part of a fuel-cell system, has been developed together with a steel plate meeting all mechanical and chemical requirements. This newly developed MPP had to achieve the objective of saving weight and package space. The use of compression molding as a manufacturing technique facilitated the use of glass mat thermoplastics (GMT) which has higher E-modules and strength compared to most of the injection molded materials. A steel plate was placed as an insert to help achieve the stiffness requirements. For the development, the existing MPP was benchmarked for its structural capabilities and its underlying functional features. Four different FRP materials were investigated in terms of their chemical and mechanical properties. PP-GMT material, which has both high mechanical performance and resistance against chemicals in the fuel cell fluid, had been chosen. Using the properties of the chosen PP-GMT material, topology optimization was carried out based on the quasi-static load case and manufacturing constraints, which gave a load-conforming rib structure. The obtained rib structure was utilized to develop the final MPP with adherence to the functional requirements of MPP. The developed plastic-intensive MPP exhibits a 3-in-1 component feature with a 55% reduction in package space and an 8% weight reduction. The MPP was virtually analyzed for its mechanical strength and compared with the existing benchmark values. Finally, a press tool was conceptualized and manufactured to fabricate the new plastic-intensive MPP, which was tested in a rig and validated in the FE model. [ABSTRACT FROM AUTHOR]

Tank facilities storing various combustible substances are a potential source of danger for the environment and human life. Fires in tanks can occur for various reasons: technical malfunctions, human factors, military operations, natural phenomena. One of the effective methods for extinguishing such fires is “sublayer” extinguishing with the help of foam of low multiplicity. The possibility of “sub-layer” extinguishing with the help of compression foam, which has unique properties, has been considered. The object of this study is the processes of stopping combustion during fire extinguishing in steel tanks for the storage of petroleum products with the use of foaming agents of increased stability, which ensure the generation of compression foam in a “sub-layer” way. A mathematical model of the movement of a submerged non-free jet of foam in the medium of motor fuel is given, which adequately describes the real physical processes that occur during “sublayer” quenching of vertical steel tanks. According to the research, it was established that the use of foam with a multiplicity of 10 (K10) is 1.56 times more effective in serving time than the use of foam with a multiplicity of 5 (K5). From an economic point of view, K10 foam also has greater advantages as the costs of the foaming agent during its generation are 3.1 times lower than when using K5 foam. The simulations demonstrated that the foaming agent consumption of the K10 foam is lower than the foaming agent consumption of the K5 foam and results in a different amount of foam coming to the surface. The simulations also showed that the volume of K5 foam increases proportionally with the feeding time, while the volume of K10 foam increases disproportionally and starts to decrease after half the time. The results from the implementation of the mathematical model were fully consistent with the results from experimental studies on extinguishing a model fire of class B. [ABSTRACT FROM AUTHOR]

Catalytic oxidative desulfurization (ODS) using titanium silicate catalysts has emerged as an efficient technique for the complete removal of organosulfur compounds from automotive fuels. However, the precise control of highly accessible and stable-framework Ti active sites remains highly challenging. Here we reveal for the first time by using density functional theory calculations that framework hexa-coordinated Ti (TiO6) species of mesoporous titanium silicates are the most active sites for ODS and lead to a lower-energy pathway of ODS. A novel method to achieve highly accessible and homogeneously distributed framework TiO6 active single sites at the mesoporous surface has been developed. Such surface framework TiO6 species exhibit an exceptional ODS performance. A removal of 920 ppm of benzothiophene is achieved at 60°C in 60 min, which is 1.67 times that of the best catalyst reported so far. For bulky molecules such as 4,6-dimethyldibenzothiophene (DMDBT), it takes only 3 min to remove 500 ppm of DMDBT at 60°C with our catalyst, which is five times faster than that with the current best catalyst. Such a catalyst can be easily upscaled and could be used for concrete industrial application in the ODS of bulky organosulfur compounds with minimized energy consumption and high reaction efficiency. [ABSTRACT FROM AUTHOR]

Chlorinated organic compounds, as contaminants in marine fuels, have caused severe damage, affecting both main and auxiliary engines. Contaminated fuels can cause serious damage to an engine and its components, corroding fuel pumps and blocking filters, for example. This affects the operation of the engine, and, in the most severe cases, vessel safety. This study considered fossil diesel containing hydrochloric acid as a possible product formed under certain conditions in fuel contaminated with COCs and its effects on carbon steel, stainless steel, tempering steel, and aluminum. Five fuel samples with different concentrations of hydrochloric acid were prepared, plus one sample of diesel and water. Metal bars were partially immersed in the fuel samples and stored at room temperature for approximately one month. A visual assessment found corrosion across the entire surface of all metal bars when exposed to fuel samples containing hydrochloric acid. Even the smallest acid content (25 ppm) caused corrosion, and the effects were already observable after only two days of exposure. Despite their acid contamination, the measured fuel properties fulfilled the standard for automotive fuels at the beginning of the test. The water in the diesel sample did not cause any visible corrosion. [ABSTRACT FROM AUTHOR]

Improvements in vehicle fuel efficiency, inflation, and the increasing adoption of electric vehicles (EV) have negatively affected the revenue-generating ability of the motor fuel tax, a major source of highway funding. Many U.S. states have adopted a surcharge levied on electric vehicles as a revenue-generating mechanism to address transportation funding challenges. In this study, we explore the determinants of the adoption of EV fees at the state level using a discrete-time event history analysis. Our findings indicate that state decisions about EV fees hinged upon the reliance on the motor fuel tax, fuel efficiency, growth in EV sales, roadway conditions, the growth in vehicle miles traveled, political environment, and the proportion of neighboring states with an EV fee. • Many states have adopted EV fees to address transportation funding challenges. • The adoption of EV fees are affected by transportation, environmental, political, and neighboring factors. • Revenue decisions such as EV fees present important opportunities for future research. [ABSTRACT FROM AUTHOR]

Fuel cell technology is a promising alternative to traditional internal combustion engines in various applications, especially in transportation applications. However, the high cost and limited lifetime of fuel cells have hindered their widespread commercialization. Accurately predicting fuel cell lifetime is crucial for reducing the cost of ownership, ensuring safety, and promoting the adoption of this technology. The objective of the present work is to develop a tool that is able to estimate the lifespan of a proton exchange membrane fuel cell and to predict its behavior to anticipate failures. Therefore, this paper contributes to proposing a multi‐input time‐series prediction network based on an echo state network, which takes the future current into consideration. A degradation trend extraction method is proposed in this paper and the remaining useful life of the fuel cell is predicted. Results have shown that the proposed methods in both short‐term and long‐term prediction have achieved satisfying prediction accuracy. [ABSTRACT FROM AUTHOR]

Superconducting electric motors are required in order to deliver lower-carbon aviation. Critical to the success and viability of operating superconducting electric motors in aviation is keeping the superconducting coils at their operating temperature. This paper examines the challenges of keeping a superconducting motor cold if it were used on a single aisle passenger aircraft such as an Airbus A320. The cooling problem is defined and different cooling scenarios are investigated to determine viability. The investigation has shown that for a motor with a superconducting rotor only (copper stator), a Stirling-type cryocooler would be sufficient. However, if the motor is to be fully superconducting, then the cooling loads of the stator, which are much higher, make mechanical refrigeration impractical and the only option is to cool the motor with the heat sink of a liquid hydrogen fuel. [ABSTRACT FROM AUTHOR]

Among fuel-dependent criteria are engine emission reduction and performance improvement, which have recently been achieved by adding nanomaterials to automotive fuels. In this study the effects of adding aluminum oxide and cerium oxide nanoparticles at four mass percentages [0.5%, 1%, 2%, and 5% (w/w)] to gasoline on engine emissions and vibrations at three speeds (1500 rpm, 2000 rpm, and 2500 rpm) was studied at Islamic Azad university of Kermanshah in 2021. Four air pollution parameters (HC, CO, O2, and lambda) and engine vibration levels for two different types of nano-additives were also analyzed. Furthermore, exhaust gases were analyzed to measure engine emission parameters; and engine vibrations were analyzed by recording vibration signals during engine operation and calculating vibration acceleration from each. The analysis indicated that nano-additives reduced CO and HC content and increased O2 content, but did not significantly affect lambda. Result of the exhaust gases analysis demonstrated that aluminum oxide nanoparticles outperformed cerium oxide nanoparticles in terms of engine emission reduction. It was also observed that adding both types of nanoparticles to the base fuel reduced the vibration amplitude; and higher nanoparticle concentrations reduced engine vibrations, with the aluminum oxide nanoparticles having the strongest effect. Overall, it was concluded that using aluminum nanoparticles as fuel additives can reduce engine emissions and vibrations. The results of the study indicated a significant improvement in reducing engine vibration and a clear reduction in pollutants. With the production of nano-additives based on Al2O3 and CeO2, the emission level of spark ignition engines and damage to the electro-mechanical parts of the car can be reduced. [ABSTRACT FROM AUTHOR]

The problems of identifying counterfeit motor fuels in real conditions are highlighted. It is noted that the use of express analyzers of motor fuels does not provide the necessary level of control over the accuracy and reliability of the results of measuring parameters of the fuel under study. The metrological support of express analyzers, the operating principle of which is based on the method of near-infrared spectroscopy, is considered. This method rejects the classical spectroscopic approaches in favor of complex multidimensional mathematical models. As a result, the analytical result becomes a forecast, since the quantitative analysis is replaced by a new form of qualitative analysis; the conventional metrological approaches become inapplicable; the category of uncertainty is replaced with a much less developed category of reliability; and typical procedures and means of accuracy control become insufficient. An approach to evaluation of metrological characteristics of express analyzers of motor fuels is proposed in case when the mathematical model for calculating the analyzed parameters cannot be accessed, since it is an intellectual property of the analyzer developers. Such approach will help determine the relevance of the express analyzer built-in model for specific grades of motor fuels. Domestic express analyzers have been studied, the measurement principles of which are based on dielectric permeability of fuels. For express analyzers based on the principles of dielectrometry and near-infrared spectroscopy, the identification of counterfeit fuel turned out to be approximately the same: an addition of 8–10 vol. % of the counterfeit component practically does not change the measurement results. Due to inability to study the original mathematical model utilized in the express analyzer software, alternative methods of evaluating the reliability of the analytical results, based on simplified models created for fuels with various added components and additives, have been proposed. It was shown that such additives make it possible to evaluate the calibration quality related to a specific component. A method has been developed to enable the evaluation of sensitivity of various types of express analyzers to unauthorized additives (variants of the addition method), which are used in the manufacturing of counterfeit motor fuels. The proposed variants of the addition method are recommended for monitoring the reliability of the results of express fuel analysis. [ABSTRACT FROM AUTHOR]

The high efficiency and environmental friendliness make hydrogen and fuel cell technology important players in today's energy market. However, the durability issue is a major setback for fuel cells' adoption in various applications, including automotive. As automotive fuel cells exhibit non-linearity and dynamic behavior, predicting their performance has become a complex task since their response changes rapidly to varying operating conditions. To enhance performance prediction reliability, this study proposes a novel recursive multi-step performance prediction method for automotive fuel cells based on conditional time series forecasting with convolutional neural network (CNN). The method incorporates a conditional CNN architecture to extract representative features from the input data and a recursive strategy to iteratively predict future values based on previous predictions. Moreover, the seasonality in the data is detected to correct the prediction results by considering the intermittent performance recoveries. Experimental results show that the proposed approach achieves high prediction accuracy, particularly for long-term performance prediction. The proposed method could have significant implications for improving the reliability and efficiency of automotive fuel cell systems. • Interval of recoverable degradation is identified by seasonality identification. • A conditional CNN is developed to mitigate error accumulation problem. • Dynamic durability test data are used for model training and validation. [ABSTRACT FROM AUTHOR]

Anisotropic colloidal particles can directionally self‐assemble, but the resulting assemblies cannot reconfigure unless the surface properties of colloidal particles change. Although external fields with adjustable inputs can guide the reconstruction of active structures after stimulating the dynamic assembly of active colloidal motors, the interaction between colloidal motors is unclear. Here, the study reports a bioinspired communication and directed assembly of peanut‐shaped colloidal motors with the emergence of ordered ribbon structures triggered by self‐generated chemical fields. The colloidal motors photocatalytically decompose the fuel to create the chemical concentration gradient fields and exert long‐range attractions on the colloidal scale, which enable colloidal motors to communicate by sensing each other, synchronizing orientation, and assembling side‐by‐side after the collision between their local flow fields. The inter‐individual communication occurs at a critical distance of ≈4.4 µm, resulting from the interplay between hydrodynamic effects, long‐ranged phoretic attraction, and short‐ranged magnetic interaction. The linear ribbons are still active owing to the symmetry breaking of the local fluid field and can be switched between rigid and flexible states according to light conditions to simulate the polymer conformation. The complexity of colloidal motors can be combined with external manipulations to manufacture active soft materials with precise and adaptive functions. [ABSTRACT FROM AUTHOR]

This study investigated spectral laser-induced fluorescence signals of dyes in fuels for automotive and aerospace applications under low temperatures and cryogenic conditions down to 183 K. For this purpose, a fluorescence chamber was developed based on cooling with liquid nitrogen. The design enabled a minimal inner chamber temperature of 153 K. Furthermore, the applicability of two-color LIF for liquid thermometry was evaluated under these conditions. The temperature determination was based on the temperature-sensitive fluorescence intensity ratio of the special dyes doped into the fuels determined in suitable spectral regions, which represented common bandpass filters. For this purpose, the fluorescence signals of the dye doped into the gasoline and jet fuel surrogate isooctane were tested as well as blends of isooctane and the ethanol biofuels E20 (comprising 80 vol.% isooctane and 20 vol.% ethanol), E40, and E100. Additionally, a realistic multi-component fuel Jet A-1 mixed with a suitable fluorescence dye was investigated. E100 was doped with Eosin-Y, and the remaining fuels were doped with Nile red. Temperature-dependent spectral LIF intensities were recorded in the range of 183 K–293 K, which simulate extreme environments for aerospace and automotive applications. Frozen fuel–dye mixtures cause significant extinction effects and prevent sufficient signal detection at low and cryogenic temperatures, defining the detection limit. A temperature decrease led to a spectral shift in the emission peaks of E100 doped with Eosin-Y toward shorter wavelengths, while the spectra of mixtures doped with Nile red were shifted toward longer wavelengths. The suggested bandpass filters produced the temperature-sensitive intensity ratio (the average over the temperature interval) of the dyes with the largest sensitivity for Jet A-1 (5.2%/K), followed by E100 (4.95%/K), E40 (4.07%/K), E20 (3.23%/K), and isooctane (3.07%/K), even at cryogenic temperatures. [ABSTRACT FROM AUTHOR]

Electrochemical reduction of gaseous nitric oxide gas is an appealing approach for simultaneously recycling nitric oxide and producing value-added ammonia. Indeed, ammonia finds applications in fertilizers production for agriculture, as a reagent in the pharmaceutical, explosive, and textile industries, and as a potential fuel for next-generation automotive fuel cells. Reduction of nitric oxide to ammonia using various electrode materials in electrochemical processes is reviewed. Materials primarily fall into two major categories: metal-based catalysts and carbon-supported catalysts. The key consideration and operational analysis to understand mechanistic reaction pathways and the selective production of product and intermediate are discussed from a prospective viewpoint. [ABSTRACT FROM AUTHOR]

To meet the required useful life targets of proton exchange membrane fuel cells (PEMFC) for long haul and heavy-duty applications, the degradation mechanisms and influences from production need to be analyzed and reduced. Therefore, new and aged PEMFCs should be examined on a macro- and microscopic scale. The purpose of this work is to analyze fuel cells from series production and compare the findings with literature. Since most of the results from literature base on laboratory cells, this research closes the gap between lab-scale experiments and large-scale production. Thereto, the bipolar plates and membrane electrode assemblies of the fuel cells of the Toyota Mirai II and the Hyundai Nexo fuel cell vehicles were examined using optical and scanning electron microscopes. Additionally, energy-dispersive X-ray spectroscopy was performed. Differences in flow fields (channel dimensions, water management), layer and membrane thicknesses, surface porosities, contact angels and layer surface conditions were investigated. Comparisons with current literature provide an opportunity to estimate the influences of the observed structures. In addition, a methodology is developed to map temperatures that result in the discoloration of the titanium bipolar plates during abusive operation. [Display omitted] • Ex-Situ preparation of MEA and BPP of fuel cells from Toyota Mirai II and Hyundai Nexo. • Measurement of layer thickness and contact angles by optical microscopy. • Cracks found by surface analyses facilitate estimations of operating conditions. • SEM-EDX analyses show materials and distribution across a cell of Toyota Mirai II. • Post-mortem analyses of bipolar plate with thermal discoloration after abuse testing. [ABSTRACT FROM AUTHOR]

For the European Union, the course of the Community's energy and climate policy as well as changes in the objectives and priorities of the Common Agricultural Policy, as reflected, among others, in rural development programs subject to ex ante, environmental and ex post evaluation, should be considered. Individual EU countries are still implementing their own programs focused on improving energy efficiency, energy modernisation and supporting renewable energy, and they also intervene in the energy market on an ad hoc basis, as was the case after the outbreak of the war in Ukraine. This article fits into such a broadly understood research perspective, and its primary goal is to identify the impact of the costs of energy consumption and the reimbursement of excise tax on motor fuels on the operational durability and financial sustainability of 103 farms belonging to the Polish FADN network, which in 2017–2021 implemented modernisation projects under the rural development program. Logistic and linear multivariate regression were used to estimate the strength, direction and significance of correlation relationships. It was found that relative energy costs were significantly negatively correlated with financial sustainability only in the linear model, while the impact of excise tax return was positive but not significant. Thus, an empirical proof of the advisability of a possible public intervention aimed at making farmers' access to energy cheaper was obtained. All public interventions in agricultural energy use should be subject to careful and systematic ex ante, mid-term and ex post assessments based on sound program theory. It is necessary to identify the cause-and-effect chains, in which the regression proposed in the article may be helpful. [ABSTRACT FROM AUTHOR]

Hydrogen is an attractive automotive fuel because it is carbon-free, abundantly available from water, and has an exceptional mass-energy density. Hydrogen storage has become a trendy topic in recent years with its ability to design low-cost, lightweight materials that can reversibly and rapidly store hydrogen near ambient conditions. Various materials-based systems, such as metal hydrides and metal-organic frameworks (MOFs), have been introduced. This paper discusses and compares each material in terms of hydrogen storage capacity, kinetics, and viability. Different types of metal hydrides, such as magnesium hydrides, complex hydrides, and intermetallic-compounds hydrides, are considered. Furthermore, promising MOFs materials such as zinc- and copper-based MOFs are mentioned. The paper also compares the materials in terms of storage cost, which is rarely discussed in the literature. Results show that metal hydrides require severe pressures and temperatures to achieve optimum storage capacity, which is difficult to obtain and maintain. On the other hand, MOFs have some advantages, such as high surface area, high pore volume, as well as rich open metal sites. However, these properties being offered via MOFs have a limitation of low hydrogen uptake at ambient temperatures for hydrogen storage. This limitation is overcome by designing MOFs with unsaturated open metal sites. Future research is needed to optimize metal hydrides and MOFs to perform better under normal operating conditions to meet the recommendations of the United States Department of Energy. [ABSTRACT FROM AUTHOR]

In 1998, the red-green Schröder government implemented the Environmental Tax Reform (ETR), raising taxes on petrol, diesel, natural gas and heating oil and introducing a new duty on electricity in Germany. At the same time, it cut non-wage labour costs by reducing public pension contributions. The goal was to achieve Germany's Kyoto Protocol emissions targets and to reduce a level of unemployment unprecedented since World War II while avoiding the burden on the public budget through revenue recycling. Employing microdata from household budget surveys of 1998 and 2003, this article analyses whether increased duties on motor fuels and electricity lead to a substantial reduction in households' consumption of these goods. Considering the ETR as a natural experiment, it uses the difference-in-differences approach in a European context with Germany as the treatment group and Italy, Spain and the UK as the control group. Ordinary least square regressions reveal that motor fuel demand is price inelastic, while electricity consumption increased despite the substantial rise in prices. Quartile regressions show that the effect of the motor fuel tax is slightly higher at the bottom than at the upper tail of the distribution supporting the notion that low-level consumers are more likely to find alternative substitutes. [ABSTRACT FROM AUTHOR]

Growing demand for renewable and sustainable energy sources has prompted research into bioethanol production as a viable alternative to hydrocarbon fuel for automobile engines. Based on their high carbohydrate content, Chlorella vulgaris microalgae were chosen for this study as a feasible biomass for bioethanol synthesis. After conducting microwave-based acid hydrolysis with varying acid concentrations of sulfuric acid (H2SO4) for 1–15 min, this study found that 3% H2SO4 for 5 min yielded the highest yield of reducing sugar (6.77 g/L). In this work, the RSM approach of central composite design (CCD) was utilized for modeling and optimization of ethanol fermentation and the MATLAB Simulink approach was employed for the simulation of ethanol fermentation. This study compared the effects of using Saccharomyces cerevisiae yeast for fermentation at different fermentation times (12 to 48 h), temperatures (28 to 32°C), and size of inoculum (0.5–1.5 g/L). Based on the actual and predicted results, the best conditions for fermentation were 36 h of time, 30°C of temperature, and 1.5 g/L of inoculum size. This gave the maximum ethanol concentration of 3.31 g/L. Furthermore, the RSM method provides minimum error and maximum R² value results for ethanol production compared to MATLAB simulation prediction (MSP). In addition, residue biomass from biofuel production is evaluated for its suitability for a further form of biofuel production. This research explores the opportunities for zero-waste biomass utilization in the development of biofuels. [ABSTRACT FROM AUTHOR]

To accurately evaluate the size and distribution characteristics of the emission particles exhausted from in-use motor vehicle engines, we independently developed a condensation particle counter (CPC) known as BHCPC. It was calibrated by conducting the calibration procedures stated in the International Standard ISO 27981. After calibration, we conducted on-site measurements and offline sampling analysis of soot particles exhausted from different engines at a motor vehicle inspection center. The calibration results show that the detection efficiency is 90% when the particle diameter is 20.6 nm and the startup response time of the instrument is 3.53 s. The experiment results show that the self-developed BHCPC demonstrates good consistency in measuring particle-number concentration (PNC) in motor vehicle exhaust, with significant count fluctuations only occurring when PNC is higher than 25,000 P/cc. Under idle conditions, motor vehicles compliant with China VI emission regulations exhibit markedly lower exhaust emission PNC compared to those adhering to China IV emission regulations. Moreover, the results obtained from the offline electron microscope analysis show that fuel content in particle samples significantly decreases as engine speed increases, and a similar variation was also found in particle size. The micro-characteristics of the particle can give potential support to the combustion diagnostics. [ABSTRACT FROM AUTHOR]