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Globally, the encouragement of using renewable fuels like biodiesel for diesel engines is driven by concerns over the fossil fuel depletion and harmful emissions. Additionally, the utilization of renewable fuel additives like diethyl ether has the potential to enhance fuel properties and boost engine performance. The aim of this paper was to construct a computer simulation using Ricardo Wave program in order to predict the performance and nitrogen oxides (NOx) emission of a diesel engine fuelled by a diesel‐biodiesel blend and a diethyl ether (DEE) as a fuel additive. The computer model was validated by comparing the simulation engine performance and NOx emission results against the corresponding experimental data for diesel, diesel‐biodiesel blend with 30% biodiesel proportion (B30), and two blends of diesel‐biodiesel‐DEE with DEE proportions of 5% and 10% on a volume basis. Also, the effect of varying the inlet air pressure on engine performance and NOx emission was compared for all investigated fuels. It was numerically demonstrated that using the DEE with an optimum proportion of 5% enhanced engine performance as it decreased engine fuel consumption by 5.9% and increased engine thermal efficiency by 9.6% compared to diesel fuel at engine full load condition. Also, a significant reduction of 20.5% in NOx emission resulted from the addition of DEE. Increasing the inlet air pressure increased engine power and decreased engine fuel consumption for all investigated fuels. Increasing the inlet air pressure from 1 to 3 bar increased engine brake thermal efficiency by almost 20% for all tested fuels. However, NOx emission increased slightly within a range from 1.7% to 7% for the different investigated fuels. [ABSTRACT FROM AUTHOR]

Today, the tightening of exhaust emission regulations in engines directs researchers to alternative fuel types. In this study investigated the impact of blending diesel fuel with bioethanol and diethyl-ether on combustion parameters and exhaust emissions in a single-cylinder DI (direct injection) diesel engine. Both numerical and experimental analyses were used to compare the in-cylinder pressure and heat release rate of various fuel blends. Fuel spray/temperature/equivalence changes in the cylinder for different crank angles were created for different fuel types. The analysis was examined various parameters such as in-cylinder pressure, temperature, heat release rate, mass fraction burned, fuel spray formations, and equivalence ratio at variable crank angles. Results showed that all blended fuels exhibited a decrease in in-cylinder maximum pressure, temperature, and heat release rates compared to 100% diesel fuel, with an increase in mass fraction burned. CO2 emissions of D90E10 (90% diesel fuel + 10% bioethanol), D80E20 (80% diesel fuel + 20% bioethanol), D80E10DEE10 (80% diesel fuel 10% bioethanol + 10% diethyl ether) and D85E10DEE5 (85% diesel fuel + 10% bioethanol + 5% diethyl ether) fuelled engine were decreased rates 2%, 2.9%, 5% and 3.8% compared to D100 (100%diesel fuel) operation, respectively. Also, the maximum pressure in the chamber was decreased rate 3% in D80E10DEE10 fuel operation, compared to diesel fuel. Based on FTIR (Fourier Transform Infra-Red) data, the lubricating oil analyses showed that there was no significant decline in oil performance after 110 h of operation with different fuel types. However, a closer examination of the AVL FIRE program data and the EDX (Energy Dispersive X-Ray) analysis of the first ring uncovered that the wear patterns observed on the ring while using D100 fuel were heavily influenced by temperature and pressure parameters. This was particularly noticeable when compared to blended fuels that included bioethanol. [ABSTRACT FROM AUTHOR]

This research investigated the performance of bentonite and Al-PILC as catalysts in ethanol conversion to diethyl ether through a dehydration reaction. The natural bentonite was intercalated with the pillaring agent Keggin-ion Al13 to obtain Al-intercalated bentonite. Al-intercalated bentonite has been synthesized using conventional stirring and ultrasonication. Al-intercalated bentonite was calcined at 400 °C for 4 h to produce Al2O3 pillared bentonite (Al-PILC). The dehydration reaction was conducted using a 0.2 g catalyst and 10 mL of ethanol with a nitrogen gas flow rate of 20 mL/min at various reaction temperatures (200, 225, and 250 °C) using a fixed bed microreactor. The characterization results reveal that Al-PILC synthesized by sonochemistry exhibits significantly higher surface area and total acidity values than bentonite and Al-PILC synthesized by conventional methods because of the formation of stable Al2O3 pillars in the interlayer spaces of bentonite. The sonochemically synthesized Al-PILC produces optimum ethanol conversion and diethyl ether yield of 46.05% and 41.11%, respectively. The conversion of ethanol and diethyl ether yield reaches an optimum result at 225 °C. Based on this study, the pillarization of bentonite using Al2O3 can enhance its catalytic properties toward diethyl ether production. [ABSTRACT FROM AUTHOR]

The objective of this study is to improve the performance of a diesel engine with direct injection using diethyl ether as an additive and pongamia methyl ester as a fuel and to minimize emissions. The optimization process considers two input factors, the load and the fuel, and evaluates nine response parameters, including brake-specific fuel consumption, brake thermal efficiency, carbon monoxide, oxygen, nitrogen oxides, smoke, and exhaust gas temperature. A series of investigations were carried out to determine the appropriate reaction. Based on the test results, a grey relational analysis was performed to determine the optimal combination of fuel and load. The analysis involved the application of grey relational grade in order to simplify the problem of multiple responses to a single response. The integration of the grey relational grade and the signal-to-noise ratio provides the performance index. The experiment showed that the most effective solution is obtained by using Pongamia methyl ester fuel with a 10% addition of diethyl ether at a load of 30 kg. [ABSTRACT FROM AUTHOR]

The compression‐ignition properties of crude Jatropha and camphor oil blends with di ethyl ether (DEE) added is covered in this research. Six fuel samples are made based on volume: 90% C70J30 with 10% diethyl ether (C70J30 + 10% DEE), 90% C30J70 with 10% di‐ethyl ether (C50J50 + 10% DEE), 70% Camphor oil with 30% crude Jatropha oil (C70J30), 50% Camphor oil with 50% crude Jatropha oil (C50J50), 30% Camphor oil with 70% crude Jatropha oil (C30750). A four‐stroke, one‐cylinder, naturally aspirated, compression‐ignition engine operating at a constant 1500 rpm with a load range of 0%–100% with a 25% interval is used for the experiment. According to test findings, the C70J30 + 10% DEE has the lowest brake‐specific energy consumption of 11.68 kJ/kWh, the maximum energy efficiency of 62.56%, and the highest thermal efficiency of 30.81%. Compared to the other biofuels examined, this puts it more in line with diesel. Additionally, blends of crude Jatropha oil and camphor oil showed at least 4.46 g/kWh of CO, 0.259 g/kWh of HC, and 74% of smoke opacity when DEE was added. However, it raises CO2 to 0.792 kg/kWh and NO to 9.54 g/kWh. The greatest peak pressure and quickest heat release are produced by adding more DEE as a fuel additive and using a larger percentage of camphor oil. It also increases the coefficient of variation of the peak pressure throughout 100 cycles. All things considered, the C70J30 + 10% DEE's CI engine features are better. [ABSTRACT FROM AUTHOR]

This research addresses the challenges of emission reduction and fuel consumption in engines by investigating modifications in fuel properties using graphene oxide (GO) nanoparticles and diethyl ether as oxygenated additives. Characterization tests were conducted to determine the size, energy, and content of graphene and oxygen molecules in synthesized GO nanoparticles. Pongamia Pinnata Oil Methyl Ester (POME) was prepared through a transesterification process and blended with diesel to obtain a B20 blend. This POME (B20) was further mixed with GO nanoparticles at 40, 80, and 100 mg L-1 concentrations and supplemented with 3 vol% of diethyl ether. The blending process involved stirring, bath sonication, and probe sonication. A Common Rail Direct Injection diesel engine was employed with a toroidal combustion chamber and a 7-hole fuel injector nozzle. The engine maintained a steady speed of 1800 rpm, an injection timing set at 23ºbTDC, and a fixed compression ratio of 18.5 while operating under five different loads. At maximum loading conditions, the addition of 100 ppm GO nanoparticles and 5 vol% of Diethyl ether resulted in a 19.7% enhancement in Brake Thermal Efficiency (BTE) and a 10.71% reduction in Brake Specific Fuel Consumption. Furthermore, there was a significant reduction observed in CO, HC, and smoke emissions by 47.9%, 70.3%, and 23.8%, respectively. The addition of these fuel additives increased combustion characteristics such as Heat Release Rate, Cumulative Heat Release Rate, peak pressure, and in-cylinder pressure, while concurrently decreasing the Ignition Delay period and Exhaust Gas Temperature. [ABSTRACT FROM AUTHOR]

Diethyl ether (DEE) can be used in diesel engines as a fuel or fuel additive. The review study was compiled from the findings of several studies in this area. The diverse techniques are employed to mitigate the detrimental pollutants emitted by diesel engines. The first approach to reducing emissions involves altering the fuel system and engine design to improve combustion, but this is an expensive and time–consuming process. The utilization of various exhaust gas devices, such as a particle filter and catalytic converter, is necessary for the second way. However, the engine performance could be negatively impacted by these tools. Additionally, these exhaust devices increases the vehicle and maintain costs. The use of different alternative fuels or fuel additives is the third way that reduces emissions while improving engine performance. The particulate matter (PM), smoke, and nitrogen oxides (NOx) are the main environmental pollutants released by diesel engines into the atmosphere. The decreasing PM and NOx emissions at the same time is practically very difficult. The majority of researches indicate that using alternative fuels, such as natural gas, biogas, and biodiesel, or blending additives with conventional or alternative fuels, is the best way to reduce emissions. However, the characteristics of the fuel have a significant influence on cycle variations, which have a significant impact on engine performance, fuel economy, and emissions. Therefore, it is very important that the results of studies on the impact of DEE on cyclic variation are evaluated together to practice applications and to guide future studies. As a result, the primary focus of this study is on the usage of DEE as a fuel or fuel additive with different diesel engine fuels. The aim of this review is to investigate, using the available knowledge in literature, how DEE affects cyclic variations. [ABSTRACT FROM AUTHOR]

To address the global demand for sustainable energy, integrating biogas into internal combustion engines is becoming more important. Homogeneous Charge Compression Ignition (HCCI) engines, known for high efficiency and low emissions, offer a promising solution. This study investigates the optimal injector location for using biogas in HCCI engines, with diethyl ether (DEE) as the pilot fuel, evaluating three positions: (i) at the port, (ii) 6 cm away (Manifold 1), and (iii) 10 cm away (Manifold 2). Through experiments and simulations, the impact of injector location on engine performance is analyzed across various parameters, including methane fractions, engine loads, and exhaust gas compositions. Results show that port injection achieves the highest first law and exergy efficiencies but increases emissions of hydrocarbons (HC), carbon monoxide (CO), and smoke. At 15 Nm load, Manifold 1 shows a 27.34 % reduction in exergy efficiency compared to port injection, while Manifold 2 exhibits an 18.49 % decrease at higher loads. Despite lower efficiencies, Manifold 1 effectively reduces harmful emissions. The study also considers exergo-economic and sustainability aspects, highlighting that while port injection is optimal for efficiency, Manifold 1 excels in minimizing HC and CO emissions, with a 50 % reduction in HC and 71.43 % reduction in CO emissions at 15 Nm load compared to port injection. Manifold 2 achieves the lowest smoke emissions across all loads. This investigation provides crucial insights into optimizing HCCI engines for biogas utilization, emphasizing injector location, fuel composition, and operating parameters to enhance performance and reduce environmental impact.

Modification of a natural zeolite from Klaten, Indonesia, as a catalyst in the dehydration of ethanol to produce diethyl ether (DEE) has been conducted. Raw Klaten natural zeolite (ZA) was modified using 1 and 2 M of an ammonium chloride solution for 24 h while stirring for 18 h, then calcined at 500 °C for 5 h under N2 gas flow produced HZA1 and HZA2 catalyst, respectively. The catalysts were characterized using XRD, BET surface area, SEM-EDX, XRF, FTIR and gravimetric acidity test using ammonia-based vapor. The dehydration process was conducted under variations of temperature (200, 250, and 300 °C) and catalyst mass of 0.1, 0.2, and 0.4 g for 20 mL of 96% ethanol. The HZA1 catalyst produced the highest yield of DEE (2.41%) at 250 °C and 0.1 g catalyst. This catalyst showed needle-like of 66.22 nm crystal size, consisting of 32.57% mordenite, the highest surface area (48.32 m2/g), crystallinity (32.93%) and Brønsted acid sites (2.75 mmol/g), the lowest pore diameter (1.77 nm) and Si/Al mol ratio (4.03). The HZA1 catalyst can be used repetitively and produced DEE yield at the second and third runs (2.40 and 2.61%).

Hyperpolarized 129Xe gas was FDA‐approved as an inhalable contrast agent for magnetic resonance imaging of a wide range of pulmonary diseases in December 2022. Despite the remarkable success in clinical research settings, the widespread clinical translation of HP 129Xe gas faces two critical challenges: the high cost of the relatively low‐throughput hyperpolarization equipment and the lack of 129Xe imaging capability on clinical MRI scanners, which have narrow‐bandwidth electronics designed only for proton (1H) imaging. To solve this translational grand challenge of gaseous hyperpolarized MRI contrast agents, here we demonstrate the utility of batch‐mode production of proton‐hyperpolarized diethyl ether gas via heterogeneous pairwise addition of parahydrogen to ethyl vinyl ether. An approximately 0.1‐liter bolus of hyperpolarized diethyl ether gas was produced in 1 second and injected in excised rabbit lungs. Lung ventilation imaging was performed using sub‐second 2D MRI with up to 2×2 mm2 in‐plane resolution using a clinical 0.35 T MRI scanner without any modifications. This feasibility demonstration paves the way for the use of inhalable diethyl ether as a gaseous contrast agent for pulmonary MRI applications using any clinical MRI scanner. [ABSTRACT FROM AUTHOR]

Numerous studies derived from medicinal herbs have been conducted to explore bioactive compounds as potential alternatives to synthetic drugs, aiming to mitigate harmful side effects and alleviate economic burdens. In this study, we assessed the safety and potential biological activities of extracts from Fomes fomentarius L. (FFL). The FFL extracts were obtained through various ethanol concentrations, as follows: 0%, 30%, 50%, 70%, and 100%, respectively. All extracts did not induce mutagenicity even up to 5 mg/plate concentration. In the assessment of antioxidant activity, only the hot water extract exhibited weaker antioxidant activity than the other ethanol extracts. Notably, all extracts exhibited significant antimutagenetic effects only with a metabolically active enzyme system (S9 mix). The condition of 70% ethanol extract displayed the most robust antimutagenic activity; thus, the extract was sequentially fractionated with solvents of varying polarities to isolate inhibitory components. After the fractionization, the diethyl ether and butanol fractions effectively suppressed the growth of mutated colonies, suggesting that those such as essential oils, vitamins, alkaloids, and flavonoids can be considered major active compounds. Overall, our study demonstrated that FFL extracts induce potent antioxidant and antimutagenic effects. Further investigations are warranted to verify specific active compounds which induce an antimutagenic effect. Our findings provide valuable insights into FFL as a promising source for potential functional food development. [ABSTRACT FROM AUTHOR]

Alternative fuels and energy sources are necessary to combat climate change and deplete fossil fuel stocks. Greenhouse gasses and environmental degradation are consequences of traditional energy sources, making the need for sustainable alternatives critical. Another feasible solution to lessen the environmental impact of transportation and industry is biodiesel and biofuels. Using an efficient approach for trash disposal is another important consideration. The manufacturing of many things has skyrocketed, leading to an explosion of trash. For a long time, waste polymers were the material of choice for many items due to their low production costs and high adaptability. The purpose of this article is to promote a more sustainable environment by addressing the challenges of conventional fuel scarcity and the disposal of polymer waste. Diesel engine's performance was studied in relation to waste polymer fuels recovered from different waste grades of waste polymer with diethyl ether added. Diesel fuel and a blend of waste polymer fuel, typically 20% and 40% by weight, are combined to provide the primary fuel. The diethyl ether additives, in concentrations of 10% and 20%, were mixed with waste polymer fuel to enhance the performance of the engines, serving as an alternative fuel source. [ABSTRACT FROM AUTHOR]

Advanced biofuels have the potential to supplant significant fractions of conventional liquid fossil fuels. However, the range of potential compounds could be wide depending on selected feedstocks and production processes. Not enough is known about the engine relevant behavior of many of these fuels, particularly when used within complex blends. Simulation tools may help to explore the combustion behavior of such blends but rely on robust chemical mechanisms providing accurate predictions of performance targets over large regions of thermochemical space. Tools such as automatic mechanism generation (AMG) may facilitate the generation of suitable mechanisms. Such tools have been commonly applied for the generation of mechanisms describing the oxidation of non‐oxygenated, non‐aromatic hydrocarbons, but the emergence of biofuels adds new challenges due to the presence of functional groups containing oxygen. This study investigates the capabilities of the AMG tool Reaction Mechanism Generator for such a task, using diethyl ether (DEE) as a case study. A methodology for the generation of advanced biofuel mechanisms is proposed and the resultant mechanism is evaluated against literature sourced experimental measurements for ignition delay times, jet‐stirred reactor species concentrations, and flame speeds, over conditions covering φ = 0.5–2.0, P = 1–100 bar, and T = 298–1850 K. The results suggest that AMG tools are capable of rapidly producing accurate models for advanced biofuel components, although considerable upfront input was required. High‐quality fuel specific reaction rates and thermochemistry for oxygenated species were required, as well as a seed mechanism, a thermochemistry library, and an expansion of the reaction family database to include training data for oxygenated compounds. The final DEE mechanism contains 146 species and 4392 reactions and in general, provides more accurate or comparable predictions when compared to literature sourced mechanisms across the investigated target data. The generation of combustion mechanisms for other potential advanced biofuel components could easily capitalize on these database updates reducing the need for future user interventions. [ABSTRACT FROM AUTHOR]

The systemic electrical signal propagation in plants (i.e., from leaf to leaf) is dependent on GLUTAMATE RECEPTOR-LIKE proteins (GLRs). The GLR receptors are the homologous proteins to the animal ionotropic glutamate receptors (iGluRs) which are ligand-gated non-selective cation channels that mediate neurotransmission in the animal's nervous system. In this study, we investigated the effect of the general anaesthetic ketamine, a well-known non-competitive channel blocker of human iGluRs, on systemic electrical signal propagation in Arabidopsis thaliana. We monitored the electrical signal propagation, intracellular calcium level [Ca2+]cyt and expression of jasmonate (JA)-responsive genes in response to heat wounding. Although ketamine affected the shape and the parameters of the electrical signals (amplitude and half-time, t1/2) mainly in systemic leaves, it was not able to block a systemic response. Increased [Ca2+]cyt and the expression of jasmonate-responsive genes were detected in local as well as in systemic leaves in response to heat wounding in ketamine-treated plants. This is in contrast with the effect of the volatile general anaesthetic diethyl ether which completely blocked the systemic response. This low potency of ketamine in plants is probably caused by the fact that the critical amino acid residues needed for ketamine binding in human iGluRs are not conserved in plants' GLRs. [ABSTRACT FROM AUTHOR]

This study aimed to change the ignition delay time by adding toluene and diethyl ether to diesel fuel and to improve the exhaust emission (CO, CO 2 , HC, smoke, and NOx) values by adding H 2 , H 2 +HHO and H 2 +HHO + O 2 gases added from the intake manifold. For this purpose, a mixing chamber has been added in front of the intake manifold. HHO is produced from a hydrogen generator, and H 2 and O 2 gas supplied from a tube is supplied to the engine running on liquid fuel. H 2 , HHO and O 2 gases were added from the intake manifold to the engine using di ethyl ether and toluene, which were added to the diesel fuel at a rate of 5% and 10% by volume. Under these conditions, the engine was started at an engine speed of 3000 rpm at engine loads of 1000 W, 2000 W and 3000 W. The results showed that all exhaust emission values decreased with adding toluene and diethyl ether to diesel fuel, and the tendency to decrease continued even more with the addition of H 2 , H 2 +HHO and H 2 +HHO + O 2. It has been found that among all fuel mixtures, H 2 + HHO + O 2 gas Decoupled fuel mixtures are effective in obtaining the best results in terms of exhaust emissions. In this case, with the addition of O 2 , combustion efficiency increased and emissions decreased. • The use of hydrogen in internal combustion engines. • The effects of the addition of H 2 , H 2 +HHO, and H 2 +HHO + O 2 to a diesel engine using toluene and diethyl ether as pilot fuel. • The effect of oxygen-rich hydrogen with additives with low evaporation temperature on emissions. [ABSTRACT FROM AUTHOR]

Cleaner energy generation on light-duty off-road diesel engines is one of the objectives of this study, which utilizes renewable diethyl ether (DEE) as a replacement for diesel to minimize the reliance on fossil diesel fuel. In an aircooled single-cylinder diesel engine, various DEE mixes of 5, 10, 15, 20 and 25% were attempted and evaluated under varying loads (0, 25, 50, 75 and 100%) in an effort to enhance the performance and emission characteristics of agriculture diesel engines and lower the environmental effect of harmful emissions. The injection pressure was optimized using computational fluid dynamics (CFD), and performance and emission outcomes were optimized through response surface methodology (RSM) techniques. The experimental results found that brake thermal efficiency and specific fuel consumption were enhanced for a higher proportion of DEE blends under increasing loads. In addition, increasing the engine load decreased CO emissions while increasing carbon dioxide (CO2), hydrocarbon (HC), and nitrogen oxide (NOx) emissions. Reduced CO, NOx, and HC emissions and increased CO2 were realized in the blended fuel samples compared to those of pure diesel fuel at increasing DEE percentages. In summary, the utilization of a 15% DEE blend and the optimization of the injection pressure to 210 bar resulted in a notable improvement of 10% in thermal efficiency and a decrease in emissions by 5% when compared to other parameters. [ABSTRACT FROM AUTHOR]

Alternative fuels can be produced from both non-edible feedstocks and edible crops. The higher production costs and contaminating nature of vegetable biofuels, which cause engine component failure, make it conceivable to encourage the synthesis of biodiesel from non-edible sources. One of the most widely utilized alternative fuels is Jatropha biofuel, which has performance levels comparable to diesel fuels and can be used with CI (Compression Ignition) engines without any modifications. However when it comes to oxidative stability properties that impact shelf life and commercialization, the majority of biodiesels—including Jatropha—are lacking. Therefore, the objective of this study was to enhance the oxidative stability and other physicochemical parameters, such performance and emission characteristics, of Jatropha biodiesel with diesel blends by adding additives like DEE (diethyl ether) and MA (moringa oleifera antioxidant). The seeds of jatropha and moringa were harvested by hand and then mechanically extracted with a screw press. A conical flask containing the precisely weighed amount of oil is filled with 50 mL of neutral alcohol. The combination is then heated for an hour using a water condenser over a bath. Using phenolphthalein indicator, the contents are titrated with KOH solution after cooling. Weight of oil taken (w)/volume of KOH used (mL) × normality of KOH is the formula used to determine the acidity value of jatropha oil. It is therefore below the minimum level set by ASTM D 675, which is 2.5 mg KOH/g. Methanol was used in the transesterification process to produce biodiesel, and potassium hydroxide (KOH) was used as a catalyst. Then, using 5 % DEE and 10 % MA additives, the physicochemical properties of jatropha biodiesel—such as density, kinematics viscosity, calorific value, and oxidative stability—were characterized. The percentage of improvement of the biodiesel's mentioned properties with these additives was 0.68 %, 2.8 %, 0.73 %, and 33.8 %, respectively. The brake thermal efficiency (BTE) of B40MA10DEE05D45 increased by 8.52 % whereas the brake specific fuel consumption (BSFC) of B50MA10DEE05D35, which is Made up of 44 % diesel, 50 % jatropha biodiesel, 5 % DEE, and 10 % MA fuels, declined by 5.14 %. As a result of these additions, the blended fuel's CO, HC, and NOx emissions were reduced by 3.51 %, 2.25 %, and 8.64 %, respectively. Therefore, a 20 % blend of Jatropha biodiesel and diesel containing antioxidants from Moringa can be used in compression ignition engines without the need for engine modifications and with high oxidation stability.

The purpose of this research is to look at performance and emission characteristics of Ethiopian Prosopis Juliflora biodiesel (JFB) blended with diethyl ether (DEE) additive in varying proportions. The experiment includes testing different biodiesel blends and DEE additive concentrations, namely D100, B100, B20DEE5, B20DEE10, B20DEE15, and B20DEE20. FT-IR (Fourier transform infra-red) analysis was employed to investigate whether necessary functional groups for a biodiesel were present. Rheometer analysis was employed to investigate how shear rate and temperature affect the shear stress and viscosity of blended fuels employed. Results show that D100 exhibits the highest brake thermal efficiency (BTE) across the load range, while B100 has the lowest. Although DEE blended fuels have lower BTE than diesel, the results are comparable. Notably, at 50 % load, B20DEE10 achieves a BTE of 31.4 %, closer to D100 at 36.7 %. Brake-specific fuel consumption (BSFC) decreases as load increases up to 50 %. While BSFC for JFB, B20, and blended fuels is higher than D100 across all engine loads, B20DEE10 shows a comparable result of 203 g/kWh versus 181 g/kWh for D100 at 50 % load. Emission levels for CO2, HC, and CO are higher for diesel compared to blended fuels, with NOx being lower for D100 and all DEE blended fuels. DEE’s higher Cetane rating and latent heat of evaporation along with shorter ignition time and faster heat release rate seems to result in lower NOx emissions, especially for medium to higher loads. At full load, B20DEE10 exhibits the lowest smoke opacity value. Additionally, FT-IR analyses confirm the presence of necessary functional groups in biodiesel and the rheological analysis shows a decrease in viscosity with increasing temperature and a shear-thinning behavior for JFB across a range of shear rates with a viscosity ranging from 203.4 to 47.5 mPa.s, with a shear rate range of 10–150 s−1.

The objective of this study is to improve the performance of a diesel engine with direct injection using diethyl ether as an additive and pongamia methyl ester as a fuel and to minimize emissions. The optimization process considers two input factors, the load and the fuel, and evaluates nine response parameters, including brake-specific fuel consumption, brake thermal efficiency, carbon monoxide, oxygen, nitrogen oxides, smoke, and exhaust gas temperature. A series of investigations were carried out to determine the appropriate reaction. Based on the test results, a grey relational analysis was performed to determine the optimal combination of fuel and load. The analysis involved the application of grey relational grade in order to simplify the problem of multiple responses to a single response. The integration of the grey relational grade and the signal-to-noise ratio provides the performance index. The experiment showed that the most effective solution is obtained by using Pongamia methyl ester fuel with a 10% addition of diethyl ether at a load of 30 kg.

Numerous studies derived from medicinal herbs have been conducted to explore bioactive compounds as potential alternatives to synthetic drugs, aiming to mitigate harmful side effects and alleviate economic burdens. In this study, we assessed the safety and potential biological activities of extracts from Fomes fomentarius L. (FFL). The FFL extracts were obtained through various ethanol concentrations, as follows: 0%, 30%, 50%, 70%, and 100%, respectively. All extracts did not induce mutagenicity even up to 5 mg/plate concentration. In the assessment of antioxidant activity, only the hot water extract exhibited weaker antioxidant activity than the other ethanol extracts. Notably, all extracts exhibited significant antimutagenetic effects only with a metabolically active enzyme system (S9 mix). The condition of 70% ethanol extract displayed the most robust antimutagenic activity; thus, the extract was sequentially fractionated with solvents of varying polarities to isolate inhibitory components. After the fractionization, the diethyl ether and butanol fractions effectively suppressed the growth of mutated colonies, suggesting that those such as essential oils, vitamins, alkaloids, and flavonoids can be considered major active compounds. Overall, our study demonstrated that FFL extracts induce potent antioxidant and antimutagenic effects. Further investigations are warranted to verify specific active compounds which induce an antimutagenic effect. Our findings provide valuable insights into FFL as a promising source for potential functional food development.

The systemic electrical signal propagation in plants (i.e., from leaf to leaf) is dependent on GLUTAMATE RECEPTOR-LIKE proteins (GLRs). The GLR receptors are the homologous proteins to the animal ionotropic glutamate receptors (iGluRs) which are ligand-gated non-selective cation channels that mediate neurotransmission in the animal’s nervous system. In this study, we investigated the effect of the general anaesthetic ketamine, a well-known non-competitive channel blocker of human iGluRs, on systemic electrical signal propagation in Arabidopsis thaliana. We monitored the electrical signal propagation, intracellular calcium level [Ca2+]cyt and expression of jasmonate (JA)-responsive genes in response to heat wounding. Although ketamine affected the shape and the parameters of the electrical signals (amplitude and half-time, t1/2) mainly in systemic leaves, it was not able to block a systemic response. Increased [Ca2+]cyt and the expression of jasmonate-responsive genes were detected in local as well as in systemic leaves in response to heat wounding in ketamine-treated plants. This is in contrast with the effect of the volatile general anaesthetic diethyl ether which completely blocked the systemic response. This low potency of ketamine in plants is probably caused by the fact that the critical amino acid residues needed for ketamine binding in human iGluRs are not conserved in plants’ GLRs.

• Premixing DEE helped engine start quickly at −40 °C temperature and 4000 m altitude. • The diesel engine using intake heater failed to start at −40 °C and high altitudes. • Premixed DEE reduces ignition delay of diesel at low temperatures and high altitudes. • Premixed DEE enhanced the evaporation of diesel and reduced fuel film thickness. • Diesel engine with DEE premixed emitted lower HC and CO during cold start. The cold-start performance poses a primary challenge influencing the reliability of diesel engines operating in plateau and low-temperature regions. An experimental investigation was conducted to assess the cold-start performance of diesel engines with premixing diethyl ether (DEE), spanning altitudes from sea level to 4000 m and ambient temperatures of −20 °C and −40 °C. The diesel engine with premixing DEE exhibited successful cold starts at all these test conditions. In comparison, the diesel engine employing intake heating failed to reach idle speed in −40 °C high-altitude conditions. The premixed DEE could generate radicals, accompanied by a minor heat release preceding the injection of diesel, facilitating ignition. Furthermore, the premixed DEE enhanced fuel evaporation and facilitated the formation of combustible mixtures with higher equivalence ratios at low temperatures. Moreover, the fuel film resulting from wall impingement with premixing DEE was thinner than that with intake heating, contributing to decreased incomplete combustion losses. Energy analysis results revealed that the diesel engine employing premixing DEE demonstrated higher indicated thermal efficiency. The cold start assistance by premixing DEE proved to be much more effective, and the test engine could start smoothly under extremely low temperatures of −40 °C and high altitudes up to 4000 m. [ABSTRACT FROM AUTHOR]

Plants can sense and respond to non-damaging mechanical stimulation such as touch, rain, or wind. Mechanical stimulation induces an increase of cytosolic calcium ([Ca 2+ ] cyt ), accumulation of phytohormones from the group of jasmonates (JAs) and activation of gene expression, which can be JAs-dependent or JAs-independent. Response to touch shares similar properties with reactions to stresses such as wounding or pathogen attack, and regular mechanical stimulation leads to changes in growth and development called thigmomorphogenesis. Previous studies showed that well-known seismonastic plants such as Venus flytrap (Dionaea muscipula) or sensitive plant (Mimosa pudica) lost their touch-induced motive responses during exposure to general volatile anaesthetic (GVA) diethyl ether. Here, we investigated the effect of diethyl ether anaesthesia on touch response in Arabidopsis thaliana. We monitored [Ca 2+ ] cyt level, accumulation of JAs and expression of touch-responsive genes. Our results showed that none of the investigated responses was affected by diethyl ether. However, diethyl ether alone increased [Ca 2+ ] cyt and modulated JAs-independent touch-responsive genes, thus partially activating touch response non-specifically. Together with our previous studies, we concluded that GVA diethyl ether cannot block the local rise of [Ca 2+ ] cyt but only its systemic propagation dependent on GLUTAMATE LIKE RECEPTOR 3s (GLR3s) channels., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier GmbH. All rights reserved.)

To address the global demand for sustainable energy, integrating biogas into internal combustion engines is becoming more important. Homogeneous Charge Compression Ignition (HCCI) engines, known for high efficiency and low emissions, offer a promising solution. This study investigates the optimal injector location for using biogas in HCCI engines, with diethyl ether (DEE) as the pilot fuel, evaluating three positions: (i) at the port, (ii) 6 cm away (Manifold 1), and (iii) 10 cm away (Manifold 2). Through experiments and simulations, the impact of injector location on engine performance is analyzed across various parameters, including methane fractions, engine loads, and exhaust gas compositions. Results show that port injection achieves the highest first law and exergy efficiencies but increases emissions of hydrocarbons (HC), carbon monoxide (CO), and smoke. At 15 Nm load, Manifold 1 shows a 27.34 % reduction in exergy efficiency compared to port injection, while Manifold 2 exhibits an 18.49 % decrease at higher loads. Despite lower efficiencies, Manifold 1 effectively reduces harmful emissions. The study also considers exergo-economic and sustainability aspects, highlighting that while port injection is optimal for efficiency, Manifold 1 excels in minimizing HC and CO emissions, with a 50 % reduction in HC and 71.43 % reduction in CO emissions at 15 Nm load compared to port injection. Manifold 2 achieves the lowest smoke emissions across all loads. This investigation provides crucial insights into optimizing HCCI engines for biogas utilization, emphasizing injector location, fuel composition, and operating parameters to enhance performance and reduce environmental impact., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors.)

Quaternary fuel blend consisting of diesel, palm-oil biodiesel (POB), diethyl ether (DEE), and ethanol is a promising low-carbon fuel solution for diesel engines. In this study, the effects of DEE, ethanol, and engine load on the brake specific fuel consumption (BSFC), nitrogen oxides (NO x), carbon monoxide (CO), and unburned hydrocarbons (UHCs) emissions of a light-duty diesel engine were statistically analyzed using analysis of variance (ANOVA). Desirability-based response surface methodology (RSM) optimization was then employed to determine the optimum quaternary fuel blend. The desired optimum quaternary fuel blend was found to be 6.78 vol% DEE and 20.00 vol% ethanol at an operating engine load and speed of 31.36 % and 2000 rpm, respectively. The engine out responses of BSFC and NO x , CO, and UHCs emissions for the optimal solution were 490.58 g/kWh, 326.84 ppm, 0.300 vol%, and 156.95 ppm, respectively. Validation of the optimized parameters was conducted through actual engine experiments and the errors were less than 5 %. The results suggest that the optimum quaternary blend can be a cleaner alternative for light-duty diesel engine applications. [Display omitted] • Optimum quaternary fuel blend reduces diesel engine emissions. • Development of a low-carbon fuel for diesel engines with quaternary blend. • Incorporating the benefits of different fuels using response surface optimization. • Diethyl ether and ethanol have significant effect on engine performance and emissions. [ABSTRACT FROM AUTHOR]

• Measured ignition delay time of ammonia/diethyl ether mixtures using a shock tube. • Proposed a new ammonia/diethyl ether model (NH 3 –DEE). • Conducted kinetic analyses using the NH 3 –DEE model. Ammonia (NH 3) can be used as a fuel in gas turbines and internal combustion engines. However, it exhibits a long ignition delay time (IDT), which could be reduced by mixing highly reactive fuels with it. Few studies have been conducted on the IDT by adding diethyl ether (DEE) as a reactive fuel to NH 3 at high temperatures. Therefore, this study explores the influence of DEE on the autoignition characteristics and chemical kinetics of NH 3 using experimental, simulation, and theoretical approaches. The IDT of NH 3 /DEE mixtures were measured using a shock tube considering DEE fractions of 0 %, 5 %, 10 %, and 30 %, equivalence ratios of 0.5, 1.0, and 2.0, pressures of 0.14 and 1.0 MPa, and temperatures of 1220–1980 K. A new NH 3 –DEE model was developed and validated against experimental data, reliably predicting the IDT. Chemical reaction kinetic analysis using this model reveals a nonlinear decrease in the IDT of NH 3 with increasing DEE content, where adding only 5 % DEE reduced the IDT by over 80 %. The rapid consumption of DEE in the initial stages leads to the generation of numerous active radicals crucial for promoting NH 3 combustion. With the increase in DEE content, the reaction flux of DEE consumed through H-abstraction reaction increases. Additionally, increasing the proportion of DEE increases the mole fraction of CH 3 in the radical pool. This increase in CH 3 , when reacting with NH 2 , results in a higher concentration of cyanide, a highly toxic species. [ABSTRACT FROM AUTHOR]

• Three catalysts "CuO-SiO 2 ,CuO-MgO-SiO 2 and CuO-MgO" have been synthesised by in situ hybridizing silica and Cu 3 (BTC) 2. • The effects of the prepared samples properties on their catalytic performances toward ethanol conversion were discussed. • The tested catalysts possessed ethanol dehydration ability rather than ethanol dehydrogenation reaction into butadiene. • Among all prepared catalysts, CuO-MgO sample attained the highest ethanol conversion with ethylene yield of 80 % at 350 °C. In the present study, the catalytic conversion of ethanol over three different CuO-based solid acid catalysts including CuO-SiO 2 , CuO-MgO-SiO 2 and CuO-MgO was investigated. The effects of catalyst properties on the catalytic performances were determined using multiple characterization techniques. The catalytic conversion reaction of ethanol was carried out at relatively low reaction temperature 250–350 °C. Data revealed that the ethanol converted products are ethylene and diethyl ether, means that the prepared catalysts possessed ethanol dehydration ability rather than ethanol dehydrogenation reaction into butadiene. All the prepared catalysts exhibited higher ethanol conversion with the increase in reaction temperatures. Diethyl ether (DEE) was found to be major product at low temperatures (up to 275 °C) for all catalysts, whereas, ethylene is the major one at the high reaction temperatures (up to 350 °C). Among all prepared catalysts, CuO-MgO sample attained the highest ethanol conversion with ethylene yield of 80 % at 350 °C. Such significant catalytic activity of the CuO-MgO solid acid catalyst mainly attributed to the largest amount of strong acid sites and superior specific surface area parameters, supposing that the catalyst can be preferred as a promising catalyst for the production of ethylene and DEE from ethanol, which is considered a cleaner technology. [ABSTRACT FROM AUTHOR]

Ammonia (NH 3) is a promising alternative clean fuel due to its carbon-free and high hydrogen content, along with the well-established infrastructure for storage and distribution. To overcome the issue of the low reactivity of NH 3 , a feasible strategy is co-burning ammonia with highly reactive fuels. Diethyl ether (DEE) is considered a promising alternative and biomass-oxygenated clean diesel substitute. Therefore, the NH 3 /DEE blend is also a promising carbon neutral alternative fuel. In this work, we measured the ignition delay times (IDTs) of NH 3 /DEE mixtures with DEE fractions (X DEE) of 0.05, 0.10, 0.30, and 1.00 at equivalence ratios of 0.5, 1.0, and 2.0, pressures of 1.75 and 10 bar, and temperature ranges from 1102 K to 1673 K in a shock tube. The DEE-NH 3 model was proposed in this work, which included the DEE sub-model, NH 3 sub-model, and some new cross-reactions between N-containing species and C-containing species. The DEE sub-model from Shrestha et al. (Fuel Communications, 2022) was modified in this work, NH 3 sub-model was from our previous work (Reaction Chemistry & Engineering, 2023). The DEE-NH 3 model was extensively validated by the IDTs, laminar flame speeds (LFSs), and species profiles (SPs) of NH 3 /DEE mixtures as well as pure DEE and NH 3. The comparison of the prediction performance between the DEE-NH 3 model and the Shrestha model was conducted for the ignition, flame propagation, and NH 3 consumption. The effects of the cross-reactions on the NH 3 /DEE ignition and combustion were studied in detail. [ABSTRACT FROM AUTHOR]

[Display omitted] • The impact of diethyl ether on the interfacial tension (IFT) of crude oil-brine was examined under varying salinity and temperature conditions. • An experimental database comprising 7,017 sets of crude oil/brine/DEE IFT data was acquired. • Six advanced machine-learning models were developed to accurately estimate the IFT of Crude oil–Brine-DEE. • Statistical analysis was conducted, demonstrating outstanding predictions for a wide range of input variables. Solvent injection, a well-established method for enhanced oil recovery (EOR), has demonstrated significant improvements in oil recovery when compared with conventional water flooding techniques. The interfacial tension (IFT) is pivotal in determining the displacement efficiency and overall performance of innovative techniques like dimethyl ether-enhanced waterflooding (DEW), which has gained substantial attention in recent years. In this study, following laboratory measurements of IFT, six advanced machine learning (ML) techniques were employed: Generalized Linear Model (GLM), Generalized Additive Model (GAM), Random Forest (RF), Support Vector Machine (SVM), Extreme Gradient Boosting (XGBoost), and Boosted Regression Tree (BRT) to model the IFT in both oil-brine and oil-brine-diethyl ether (DEE) systems. The analysis is based on an extensive dataset comprising 7,017 data points for oil-brine and 6,949 data points for oil-brine-DEE systems obtained from experimental studies. The findings indicate that the developed RF model excels in predicting IFT, boasting a remarkable coefficient of determination (R2 = 0.99) along with the lowest root mean squared error (RMSE = 0.2), mean squared error (MSE = 0.04), and mean absolute error (MAE = 0.13). The study underscores the significance of optimizing salinity levels to achieve the most substantial reduction in IFT. This reduction is attributed to the enhanced migration of polar components, such as asphaltene molecules, to the interface of the oil-brine system. Moreover, the research highlights a synergistic decrease in IFT when both DEE and soluble ions are present, resulting in the lowest IFT at around 2 mN/m in 40,000 ppm salinity (S 2) at 70 °C (T 3). This indicates that the adsorption of DEE at the water–oil interface forms a layer capable of adsorbing ions, thereby enhancing the layer's thickness. As a result, the oil–solvent-ion layer becomes thicker compared to the oil-ion layer, leading to the maximum decrease in IFT. Additionally, with increasing temperature up to 70 °C, the IFT of both systems demonstrated a downward trend, as evidenced by all experiments. The outcomes of this study have the potential to enhance our comprehension of the underlying mechanisms involved in water-soluble solvent EOR techniques. [ABSTRACT FROM AUTHOR]

In this work, the explosion limits of three different fuels: hydrogen (H 2), propane (C 3 H 8 , C 3), and diethyl ether (DEE, C 2 H 5 OC 2 H 5 , C 4), are investigated based on detailed chemical kinetics. The results reveal that the explosion limit of H 2 O 2 exhibits the typical Z-shape, while C 3 H 8 O 2 exhibits a single-NTC response, and DEE-O 2 displays a double-NTC response. Sensitivity analysis indicates that the appearance of the NTC response in both the C 3 and DEE fuels is intricately linked to low-temperature reaction paths. Moreover, the extents of the NTC responses are comparable for these two fuels with similar low-temperature reaction paths, but operate under different temperature conditions. Specifically, the double-NTC response observed in DEE is attributed to its primary C H and C O bonds, generating C 4 and C 2 radicals. The oxygen addition and the subsequent pathways of these radicals dominate in distinct temperature ranges. In contrast, C 3 H 8 only possesses the C H bond, resulting in a single-NTC response, as OH radicals are mainly released by C 3 radicals through oxygen addition, isomerization, and decomposition reactions. The results of binary fuel mixtures with H 2 addition indicate that the reactivity of H 2 controls the low-pressure and high-temperature regime, while the C 3 and DEE fuels dominate the high-pressure and low-temperature regime. Additionally, a triangular crossover regime is identified between these two regimes due to the switchover of the reactivity. Sensitivity analysis further reveals the transition of the dominating reactions related to different fuels at various pressure-temperature regimes. Finally, based on the explosion limits of the multi-component mixtures, a detailed explosion regime diagram is proposed for carbon-free fuel (H 2), alkane fuel (C 3 H 8), and oxygenated ether fuel (DEE). This new regime diagram provides valuable insights for the investigation and utilization of ether fuels and the mixture of different fuels. [ABSTRACT FROM AUTHOR]

Alternative fuels can be produced from both non-edible feedstocks and edible crops. The higher production costs and contaminating nature of vegetable biofuels, which cause engine component failure, make it conceivable to encourage the synthesis of biodiesel from non-edible sources. One of the most widely utilized alternative fuels is Jatropha biofuel, which has performance levels comparable to diesel fuels and can be used with CI (Compression Ignition) engines without any modifications. However when it comes to oxidative stability properties that impact shelf life and commercialization, the majority of biodiesels-including Jatropha-are lacking. Therefore, the objective of this study was to enhance the oxidative stability and other physicochemical parameters, such performance and emission characteristics, of Jatropha biodiesel with diesel blends by adding additives like DEE (diethyl ether) and MA (moringa oleifera antioxidant). The seeds of jatropha and moringa were harvested by hand and then mechanically extracted with a screw press. A conical flask containing the precisely weighed amount of oil is filled with 50 mL of neutral alcohol. The combination is then heated for an hour using a water condenser over a bath. Using phenolphthalein indicator, the contents are titrated with KOH solution after cooling. Weight of oil taken (w)/volume of KOH used (mL) × normality of KOH is the formula used to determine the acidity value of jatropha oil. It is therefore below the minimum level set by ASTM D 675, which is 2.5 mg KOH/g. Methanol was used in the transesterification process to produce biodiesel, and potassium hydroxide (KOH) was used as a catalyst. Then, using 5 % DEE and 10 % MA additives, the physicochemical properties of jatropha biodiesel-such as density, kinematics viscosity, calorific value, and oxidative stability-were characterized. The percentage of improvement of the biodiesel's mentioned properties with these additives was 0.68 %, 2.8 %, 0.73 %, and 33.8 %, respectively. The brake thermal efficiency (BTE) of B40MA10DEE05D45 increased by 8.52 % whereas the brake specific fuel consumption (BSFC) of B50MA10DEE05D35, which is Made up of 44 % diesel, 50 % jatropha biodiesel, 5 % DEE, and 10 % MA fuels, declined by 5.14 %. As a result of these additions, the blended fuel's CO, HC, and NOx emissions were reduced by 3.51 %, 2.25 %, and 8.64 %, respectively. Therefore, a 20 % blend of Jatropha biodiesel and diesel containing antioxidants from Moringa can be used in compression ignition engines without the need for engine modifications and with high oxidation stability., Competing Interests: The authors whose names are listed immediately below certify that they have NO affiliations with or involvement in any organization or entity with any financial interest (such as honoraria; educational grants; participation in speakers’ bureaus; membership, employment, consultancies, stock ownership, or other equity interest; and expert testimony or patent-licensing arrangements), or non-financial interest (such as personal or professional relationships, affiliations, knowledge or beliefs) in the subject matter or materials discussed in this manuscript., (© 2024 The Authors. Published by Elsevier Ltd.)

[Display omitted] • Impact of diethyl ether on soot nanostructures studied for two diethyl ether-diesel blends. • Increasing diethyl ether content leads to higher disorder in nanostructures. • TGA curves reveal improved soot reactivity with moderate increase in diethyl ether content. In accordance with the European commission's renewable energy proposal for 2030, advanced biofuels should be blended at a minimum of 3.6 % with conventional fuels used for powering internal combustion engines. Ethers, which may be produced using modern production methods from sustainable sources like biomass, may be crucial in this regard in the future. This study demonstrates the impact of diethyl ether as a blend component (mixed with diesel) on the characteristics of the soot generated from the diethyl ether-atmospheric diesel's combustion. The soot used in this work came from a smoke point lamp that burned a mixture of diesel and diethyl ether as per ASTM D1322 standard. Diethyl ether (DEE) and diesel (D) were combined in the following blends: DEE5D (5 % diethyl ether and 95 % diesel v/v), and DEE20D (20 % diethyl ether and 80 % diesel v/v). The obtained soot was characterized in detail using the following: elemental analyzer, X-Ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDX), scanning electron microscopy (SEM), transmission electron microscopy (TEM), RAMAN spectroscopy, thermogravimetric analysis (TGA), and proton nuclear magnetic resonance (1H NMR) spectroscopy. According to the results from XRD and Raman spectroscopy, the soot nanostructure is influenced by the amount of diethyl ether present in the mixture, which raises the reactivity. The results of the elemental analyzer and 1H NMR matched those of the TGA's soot reactivity (oxidations). The results from the SEM and TEM tests, however, were not enough to support the experimental findings. [ABSTRACT FROM AUTHOR]

• Combined a shock tube with a laser absorption system for the combustion diagnostics. • Temperature, CO, CO 2 , H 2 O, NH 3 , and NO time-histories were simultaneously measured during ammonia/oxygenated hydrocarbons. • Kinetics models are detailly analyzed and improved by updating the rate constants of some reactions. Blending ammonia with highly active fuels (hydrogen, hydrocarbons, oxygenated hydrocarbons, etc.) has been identified as an efficient way to improve the mixture's reactivity. In this study, the temperature, CO, CO 2 , H 2 O, NH 3 , and NO time-histories were measured simultaneously during the oxidation of ammonia/ethanol and ammonia/diethyl ether (DEE) blends (equivalence ratio ϕ ∼ 1.2) using mid-infrared laser absorption spectroscopy behind reflected shock waves. Various models (ten for ammonia/ethanol and three for ammonia/DEE) were selected to perform the simulation and compared with the measurements. The predictions are very different for both mixtures, among which the CRECK model was selected to perform discussion and kinetics analyses for the ammonia/ethanol mixture and the Shrestha 2022 model was selected for the ammonia/DEE mixture. The CRECK model performs well in predicting the temperature rise/plateau, H 2 O formation rate/plateau, CO consumption rate/plateau, and CO 2 formation rate. However, it underpredicts the CO formation rate and slightly overpredicts the CO 2 plateau and NH 3 consumption rate; for the NO time-history, the CRECK model well captures the rapid NO formation but underpredicts the near-equilibrium NO concentration and gives an unnormal initial NO production. The Shrestha 2022 model accurately predicts the plateaus of temperature and H 2 O, but significantly underpredicts the reactivity of the ammonia/DEE mixture and overpredicts the near-equilibrium NO concentration. According to the kinetics analyses, key reactions affecting the species' time-histories were selected. Fourteen reactions in the CRECK model and eight reactions in the Shrestha 2022 model were updated by the reported data or estimations to improve the predictions. However, discrepancies still exist, which are mainly located in the CO formation and NH 3 consumption rates. Further effort should mainly focus on these two aspects, as well as the interactions between oxygenated hydrocarbons and ammonia at high temperatures. [ABSTRACT FROM AUTHOR]

• Combustion characteristics of DEE, WCO biodiesel, and jet A-1 investigated in a LPP system. • DEE addition significantly improves combustion characteristics. • NO x , CO, and UHC levels reduced for W20D20 by 38.4%, 68%, and 69.6%, respectively. This paper is a lab-scale experimental study of the impact of employing diethyl ether (DEE) as an additive to waste cooking oil biodiesel with Jet A-1 on the combustion as well as emission features of a swirl-stabilized premixed flame. First, waste cooking oil biodiesel with a volume fraction of 20% was blended with Jet A-1 and symbolized as W20. Then, diethyl ether with a volume fraction of 20% was blended with 20% biodiesel and 60% Jet A-1, symbolized as W20D20. The three test fuels (W20, W20D20 blend, and pure Jet A-1) were premixed with preheated air and pre-vaporized before being admitted to the vertical cylindrical combustor having an inner diameter of 150 mm and a length of 500 mm via a swirl burner (radial type) of 0.55 swirl number and 8 straight vanes with an angle of 45°. Local flame temperatures and emissions were measured and recorded at 350 °C of preheated air with a constant equivalence ratio (φ) of 0.85. According to the findings, a relatively wide range of flame temperatures was observed in the flame of the W20 blend, while the W20D20 blend had a flame temperature distribution very close to that of the Jet A-1. The W20D20 blend reduced UHC emissions by 69.6%, CO emissions by 61.4%, and NO x emissions by 12.5% relative to Jet A-1 at the combustion chamber outlet. Overall, adding DEE to biodiesel significantly impacts both combustion and emission profiles. [ABSTRACT FROM AUTHOR]

• In-situ IR characterization shows more C x H y * species from cracking of butanol while more unsaturated ketones from diethyl ether (DEE). • Reforming of ethanol generates more O-containing species, making coke more aliphatic and thermally unstable. • Reforming of butanol and DEE forms much more coke than from ethanol, due to aggregation of abundant carbonaceous intermediates. • Carbon-rich intermediates from butanol or DEE forms coke of aromatic nature with high crystallinity. • Coke from DEE is more defective with rough surface, while that from butanol is more graphitic with smooth surface. Molecular structures of organics play key roles in determining the tendency of coking and property of coke through governing reaction intermediates formed. Diethyl ether (DEE) can be produced from etherification of ethanol and has same carbon number with n-butanol (butanol), while they may show distinct coking behaviors in steam reforming (SR). Herein, SR of DEE, ethanol and butanol over Ni/SBA-15 catalyst were performed, aiming to probe impacts of ether functionality and length of carbon chain of the alcohols on coke formation. The results indicated that cracking of DEE formed C x H y * species and unsaturated ketone intermediates, serving as precursors of coke. Dissociative adsorption of butanol formed abundant C x H y * species even from 100 °C, due to its longer carbon chain and lower oxygen content. In comparison, abundant oxygen-containing intermediates were generated from degradation of ethanol and reactions with steam. Abundant C x H y * species from DEE and butanol prompted formation of more coke than that from ethanol (60.6 % of coke in the catalyst for DEE, 66.8 % for butanol and 32.9 % for ethanol). Moreover, the coke from SR of ethanol was thermally less stable than that from DEE or butanol, due to the involvement of more oxygen-containing intermediates, which resulted in more aliphatic coke of amorphous form in ethanol reforming. Additionally, the coke from DEE reforming was more defective with carbon nanotube form of thick walls and little internal cavity. The coke produced from butanol reforming was more graphitic and mainly in carbon nanotube form of smooth surface. Varied abundance of C x H y * and ketone species in reforming of DEE and butanol created such a difference. [Display omitted] [ABSTRACT FROM AUTHOR]