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This combustion system can also be used in conventional diesel combustion mode, in which it has also shown good performance.
Given the importance of these phenomena on the subsequent mixing and combustion processes, the results hereby presented are of interest for diesel engines injectors and combustion chambers designers.
These results indicate that the flame temperature correlations originally developed for divided-chamber diesel engines can be applied to direct-injection diesel engines.
Thus gasoline at desired amounts can be injected into inlet air and the engine operates mainly due to diesel principle.
Instead of using both degrees of freedom to control the center of combustion only, we propose a method that simultaneously controls the combustion phasing and minimizes the amount of diesel used.
), which are favourable for combustion in a standard Diesel engine, and offer the possibility to overcome the classical NO x -PM trade off.
Therefore, it is necessary to study the mechanism of deposits formation and development in engine combustion chamber when using traditional diesel or biodiesel.
This model will help researchers to initially build the database effectively to determine the deposits formation mechanism in the combustion chamber of diesel engines when using different fuel.
Results show that this combustion model accurately simulates the diesel combustion process.
which are favourable to be combusted in a standard Diesel engine and allow the potential to overcome the classical NOx-PM trade off.

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What are the current challenges and limitations associated with green hydrogen warehousing?
5 answers
The current challenges and limitations associated with green hydrogen warehousing include technical, safety, legal, and social acceptance barriers. Geological and reservoir constraints, technical limitations, legal barriers, and social acceptance issues hinder the large-scale underground storage of hydrogen. Interactions of hydrogen with rocks and fluids, safety concerns, lack of storage regulations, and the need for public awareness are key obstacles to overcome for efficient green hydrogen warehousing. Additionally, the need to reduce the cost of green hydrogen production significantly to ensure economic feasibility at a large scale is a crucial challenge in the storage and distribution of green hydrogen. Proper security measures throughout production, storage, and utilization are essential due to the flammability nature of hydrogen, adding another layer of challenge to its warehousing.
Which are the most implemented feasible and profitable treatment technologies for used tire waste?
5 answers
The most implemented feasible and profitable treatment technologies for used tire waste include thermal treatment in organic solvents, coagulation detoxification combined with biodegradation, catalytic pyrolysis using spent fluid catalytic cracking catalysts, and catalytic cracking treatment methods. Thermal treatment in organic solvents at 200–300 °C has shown effective solubilization of waste tires. Coagulation detoxification combined with biodegradation has demonstrated nearly 90% removal of organic matter from tire pyrolysis wastewater. Catalytic pyrolysis using spent fluid catalytic cracking catalysts has reduced the activation energy of waste tire pyrolysis, enhancing its efficiency. Additionally, catalytic cracking treatment methods have been developed to address issues like low recovery rates and large carbon black granules in waste tire treatment. These technologies offer promising solutions for the environmentally friendly and economically viable management of used tire waste.
What is the rpm when converting waste cooking oil to biodiesel utilizing banana peel ash catalyst?
4 answers
The rpm used when converting waste cooking oil to biodiesel utilizing banana peel ash catalyst was 6000 rpm. Additionally, the synthesis of a solid base catalyst from a mixture of ripe and unripe plantain peels for biodiesel production involved a reaction temperature of 45°C, a reaction time of 45 minutes, and a catalyst amount of 0.5 wt%. Furthermore, the transesterification of waste cooking oil using a catalyst derived from banana stem ash at room temperature for 20 minutes resulted in a 5% catalyst addition and a yield of 80.31%. The study on producing biodiesel from waste frying oil with a CaO/K2O-ZnO catalyst achieved a 95% yield at 65°C with a 3%wt catalyst load in 2 hours.
How does flame temperature affect emissions from wood combustion?
5 answers
Flame temperature plays a crucial role in influencing emissions during wood combustion. Higher temperatures lead to the decomposition of organic compounds, affecting emission levels. At 600 °C, a decrease in oxygen concentration results in a significant increase in carbon monoxide (CO) and total organic carbon (TOC) emissions. Methoxyphenols, common in traditional wood burning emissions, decrease at higher combustion temperatures above 800 °C, forming carcinogenic polycyclic aromatic compounds (PACs). Varying primary air temperatures in combustion chambers affect emission trends, with CO and THC emissions higher at simpler cycle modes. Co-combustion of wood and oil shale at high heating rates shows a shift in ignition temperatures, impacting emission profiles. Lower exit temperatures during wood combustion lead to increased benzene, toluene, and formaldehyde emissions, correlating with CO concentrations.
How does temperature affect the combustion of wood and emissions?
5 answers
Temperature plays a crucial role in the combustion of wood and the subsequent emissions generated. Higher temperatures can lead to shifts in decomposition steps during combustion, affecting ignition temperatures and complicating distinctions in wood combustion. In the case of innovative lignocellulosic biofuels, varying temperatures in the combustion chamber influence droplet penetration depth, mixture formation rates, and emissions formation, with higher temperatures enhancing combustion efficiency. Additionally, the influence of temperature on emissions like carbon monoxide (CO) and total organic carbon (TOC) during wood combustion was observed, showing that at 600 °C, lower oxygen concentrations in the atmosphere can significantly increase CO and TOC concentrations in emissions. Therefore, controlling and optimizing combustion temperatures is essential for efficient wood combustion and minimizing harmful emissions.
How does impact of plastic waste pyrolysis?
4 answers
Plastic waste pyrolysis offers a sustainable solution by converting plastic waste into valuable resources like oil and gas, thus mitigating environmental issues caused by plastic accumulation. The process involves thermal degradation of plastics in the absence of oxygen, producing pyrolysis oil and gas with high energy content. Pyrolysis can address the twin challenges of plastic waste disposal and fossil fuel depletion, providing an alternative source of fuel while reducing the demand for virgin oil. Additionally, the use of catalysts derived from renewable sources can enhance the efficiency of plastic pyrolysis, promoting the production of valuable chemicals and reducing the environmental impact of plastic degradation. Overall, plastic waste pyrolysis presents a promising avenue for sustainable waste management and energy recovery, contributing to a circular economy approach.
How to detonate ammonium nitrate?
5 answers
Detonating ammonium nitrate can be achieved through various methods outlined in the provided research contexts. One approach involves preparing heavy ammonium nitrate-fuel oil explosives, which significantly enhance detonation performance and stability. Another method involves utilizing plastic micro-powder within the explosive mixture, improving explosive performance and reducing toxic gas emissions post-explosion. Additionally, a heavy ammonium nitrate-fuel oil explosive with detonator sensitivity can be produced using chemical sensitization, resulting in favorable detonator sensitivity and large capacity power for blasting operations. Furthermore, a modified explosion-proof agent can be employed to prepare totally explosion-free crystal ammonium nitrate, enhancing safety and stability during storage and usage. These innovative approaches offer diverse ways to effectively detonate and utilize ammonium nitrate in various industrial applications.
What is the advantage and disadvantage of multivariate analysis?
4 answers
The advantage of multivariate analysis lies in its ability to provide more precise and less biased estimates for single outcomes by "borrowing strength" across multiple outcomes, enabling inferences to be drawn across various parameters. On the other hand, a disadvantage of multivariate analysis is its increased complexity, where potential borrowing of strength may not always be achieved, leading to possible estimation issues and additional modeling assumptions. Multivariate data analysis (MVDA) has been shown to be a powerful tool in various fields like biotechnology and bio-processing, aiding in the design and optimization of bioprocessing systems by identifying key variables, reducing experimental time, and enhancing product quality. Additionally, multivariate statistical procedures have proven efficient in identifying trends and subtle differences in complex datasets, contributing to a better understanding of combustion processes and practical applications like tracing engine emissions.
How the mechanisms of particle burning in difussion regime vs kinetic regime ?
4 answers
The mechanisms of particle burning in diffusion and kinetic regimes exhibit distinct characteristics and are influenced by various factors, including particle size, concentration, and environmental conditions. In the diffusion regime, the reaction rate is primarily limited by the rate at which reactants are transported to the reaction site. This is evident in the high-temperature surface oxidation of particulate boron, where multi-component gas-phase diffusion plays a significant role in the combustion process. The model for boron particle combustion incorporates both gas-phase and heterogeneous surface oxidation mechanisms, highlighting the importance of adsorption and desorption steps in the diffusion-controlled regime. Conversely, in the kinetic regime, the reaction rate is governed by the intrinsic chemical kinetics of the reactants. This is observed in the combustion of solid fuel-particle suspensions, where the reaction of solid particles in a rapidly-heated oxidizing gas can proceed via a one-step surface reaction. The onset of chemical reaction in this regime can occur through ignition of a single particle or an explosion-like manner in dense particulate suspensions, demonstrating the criticality and size-dependence of the kinetic regime. Furthermore, the kinetic regime's characteristics are also illustrated in the study of self-propelling particles, where the alignment of particle velocities occurs rapidly due to local interactions, leading to larger regions of aligned velocities. This fast kinetic regime precedes a slower hydrodynamic regime, indicating a transition from kinetic to collective dynamics. Additionally, the influence of microporous areas and devolatilization residues on carbon combustion underlines the complexity of the kinetic regime, where modifications to existing models are necessary to accurately predict combustion rates. Similarly, the kinetic scheme for biomass and sewage sludge combustion, involving devolatilization and char burnoff, emphasizes the role of kinetic parameters and oxygen concentration in determining reaction rates. In summary, particle burning in the diffusion regime is largely influenced by transport processes, while in the kinetic regime, the focus shifts to the chemical kinetics and physical mechanisms governing the reactions. The transition between these regimes and their distinct features are crucial for understanding and modeling combustion processes accurately.
What is aluminum combustion mechanisms on Melt-dispersion can occurs ?
4 answers
Aluminum combustion, particularly through the melt-dispersion mechanism (MDM), is a complex process influenced by various factors, including particle size, temperature, and the presence of an oxide shell. The MDM is characterized by the rapid melting of aluminum (Al) under conditions that induce high pressures within the particle, leading to the spallation of the oxide shell and dispersion of liquid Al clusters. These clusters, free from the diffusion limitations typical of larger particles or slower heating conditions, react rapidly with the surrounding environment. For nano-sized Al particles, the combustion process benefits from the unique properties of nanoparticles, such as low ignition temperature and fast energy release, despite the challenges of agglomeration. The combustion characteristics of these agglomerates maintain the advantages of single nanoparticles, including a low ignition temperature and a rapid energy release rate, facilitated by heat accumulation effects. Theoretical and experimental studies have confirmed the MDM for both nano and micron-sized Al particles, suggesting that controlling certain parameters during particle synthesis could enable micron-scale particles to achieve the reactivity of nanoscale counterparts. Critical experiments with Al and MoO3 thermites have further supported the MDM over the diffusion oxidation mechanism, indicating that flame propagation velocities and oxidation rates are significantly influenced by the Al nanoparticle's physical properties. Additionally, absorption spectroscopy studies have provided insights into the gas-phase species present during combustion, offering evidence contrary to some predictions of the MDM but still highlighting the mechanism's relevance. Moreover, numerical studies exploring ignition and combustion mechanisms in reactive systems have shown how the size and distribution of Al particles can affect ignition times and flame structures, emphasizing the role of particle characteristics in determining combustion behavior. Innovations in combustion systems and aluminum melting furnaces also reflect the importance of efficient and controlled combustion processes for industrial applications. In summary, the melt-dispersion mechanism in aluminum combustion is a multifaceted process influenced by nanoparticle properties, synthesis parameters, and combustion conditions, with significant implications for improving the efficiency and reactivity of aluminum-based energetic materials.
How do TiO2 NPs affect the production of betalains?
5 answers
TiO2 nanoparticles (NPs) can impact the production of betalains by selectively impregnating them onto TiO2 nanoparticles. These nanoparticles have been shown to have low toxicity towards certain organisms, such as Pichia pastoris, and can even positively affect the production of unsaturated fatty acids (UFAs). However, when it comes to plants like Mentha arvensis, exposure to TiO2 NPs can lead to altered nutrient acquisition, reduced biomass, and changes in the relative peak area of major oil constituents, affecting the production of betalains. Additionally, foliar application of TiO2 NPs on tomato plants has been found to trigger changes in antioxidant system activity and lipid peroxidation, which can further influence the production of betalains. These findings highlight the diverse effects of TiO2 NPs on different organisms and their potential impact on betalain production.