In fields of agriculture, ammonium nitrate is the most often used chemical fertilizer. Its physicochemical qualities are also applied in the explosive sector because of its affordability and ease of accessibility. But for anti-social objectives, this characteristic has made it more appealing. In order to avoid this, scientists have concentrated on adding different compounds to the ammonium nitrate synthesis process in order to lower its enthalpy.
The primary focus of this study was on the effects of ammonium nitrate on the plant’s ability to reduce nitrogen concentration and minimize caking phenomena. The plant’s ability to absorb heavy metals was not affected by the addition of zinc borate and magnesium nitrate, as evidenced by the significantly reduced results of calorimetry tests.
The findings of the instrumental examination showed that even with the addition of 0.1% of the study’s ingredients―zinc borate, and magnesium nitrate―considerably enhanced the crushing strength of ammonium nitrate. With the results in this instance, it can be said that ammonium nitrate’s inclination to deteriorate reduces and its shelf life improves. It was discovered that the reaction medium with the highest crushing strength is the one to which all three chemicals are introduced, even if their crushing strengths are comparable when applied separately.
The peak heights in the ammonium nitrate content in anion and cation analysis in ion chromatography, however, show that the low quantities of boron content―a heavy metal of the chemicals used―are the cause of this. According to nitrogen analysis, there is no impact on the nitrogen concentration of ammonium nitrate when it comes to agricultural use. It was discovered that boron compounds significantly lowered the enthalpy of ammonium nitrate when DSC analysis was carried out as a calorimetric value. It was discovered that the tendency to detonate was greatly decreased when all three chemicals were added since there was no exothermic peak in the combustion reactions. An electron microscope was used to assess surface porosity, another component influencing the detonation process.
The addition of all three compounds to the ammonium nitrate surface results in the smallest and least number of porosity when compared to the surface where each compound is added separately. It has been discovered that reducing surface porosity may change reactivity but it does not lower detonation enthalpy.

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Detonation is a high-speed combustion phenomenon in which shock waves and chemical reaction waves interact, leading to rapid temperature and pressure increases that drive chemical reactions. Stability in detonation propagation is highly sensitive to the equivalence ratio (Φ) and the initial droplet size distribution, both of which significantly impact energy release and combustion efficiency. This study investigates two-phase detonation behavior using a two-dimensional Eulerian-Eulerian model under high-temperature and high-pressure ignition conditions. The effects of varying equivalence ratios and liquid fuel droplet distributions on detonation wave propagation were analyzed. The results indicate that wider droplet size distributions improve detonation stability by reducing fluctuations associated with incomplete combustion and droplet fractionation. These findings provide insights into optimizing fuel injection strategies for advanced propulsion systems, including rotating detonation engines, where stable and efficient wave propagation is essential.

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The electrolytic ignition of an energetic ionic liquid (EIL) composed of a binary mixture of ammonium dinitramide (ADN) and hydroxylethylammonium nitrate (HEHN) was investigated. A voltage was applied to the ionic liquid (ADN/ HEHN) using six different cathode electrode materials (Mo, Fe, Pt, Ni, and Ta), and the time from voltage application to ignition and current immediately after voltage application was compared. The results demonstrated that the current measured immediately after voltage application and the reciprocal of the ignition delay time for each electrode material followed the order: Fe>Ni>Mo>Pt>Ta and Fe>Mo>Pt>Ni>Ta. The current exhibited a volcano-shaped trend with respect to the d-band center of the transition metal elements, reaching its maximum at a specific d-band center. The reciprocal of the ignition delay time presented a trend similar to that of the current, with the highest value observed for Fe and the lowest for Ta. However, a clear volcano-shaped trend was not observed, likely due to the influence of the pyrolysis reaction that proceeds simultaneously with the electrolysis reaction. This study demonstrates that electrode materials with an optimal d-band center can enhance the electrolytic response immediately after the application of voltage.

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In this study, the novel method was used to visualize the detonation initiation process by the high-speed spherical projectile using the soap bubble filled with the combustible mixture. The experiments were conducted using the stoichiometric hydrogen-oxygen mixtures with three argon dilution ratios of 40%, 50%, and 70% (2H₂ + O₂ + 2Ar, 2H₂ + O₂ + 3Ar, and 2H₂ + O₂ + 7Ar) in order to investigate the effect of the effective activation energy of the mixture on the criteria of detonation initiation by the projectile. The combustion phenomena around the projectile were observed using the shadowgraph optical system and the high-speed camera. The observation using the soap bubble indicated that the detonation initiation process included the multiple detonation initiations around the projectile that eventually developed into the spherical self-sustained detonation, when the Mach number of the projectile was lower than the Chapman-Jouguet (C-J) detonation Mach number. The initiation criteria based on the detonation cell width was consistent in the 2H₂ + O₂ + 2Ar and 2H₂ + O₂ + 3Ar mixtures, however, the detonation initiation was not observed even if the condition well above the criticality of other two mixtures in the 2H₂ + O₂ + 7Ar mixture, which indicated that the reduction of effective activation energy due to the high argon dilution ratio had the effect to reduce the capability of detonation initiation by the high-speed projectile. Two dimensionless parameters, which characterized the rapidness of the exothermic reaction and the induction length behind the shock wave, were applied to separate the conditions between the shock-induced combustion and the detonation initiation regardless of the argon dilution ratio, and the dimensionless parameters was able to separate the conditions for the detonation initiation, which could not be separated by the cell width.

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A thermodynamic program that can estimate the detonation characteristics of energy materials using KHT and KH equations of states (EOSs) has been developed. The molecular constants and thermodynamic data for gaseous species for detonation products were referred to the database in the KHT code. Three empirical parameter sets for KH EOS were examined and the results were compared with the results of KHT EOS. The empirical parameters of KH EOS, which were derived logically in 1952, could reproduce the results of KHT relatively well in the high pressure region. Moreover, the improved empirical parameter set of KH EOS was obtained by fitting on the results of KHT EOS. As a result, the C-J isentropic lines obtained using KHT and KH EOSs were equivalent.

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HEGPs (High energetic green propellants), the liquid monopropellants based on energetic ionic liquid including Hydroxyl ammonium nitrate (HAN) or Ammonium dinitramide (ADN) are considered promising candidates of alternatives to conventional hydrazine. Yet, insufficient atomization due to the high viscosity of the HEGPs causes a lack of thruster performance, and many parts of the atomization mechanism of the green monopropellants, notably the break-up behavior in the initial part of the injection, remain unexplained. This paper conducts a series of injection experiments with green monopropellants in various conditions, following up with a visual investigation of the injected propellant flow behavior. After explaining the methodology of the visual analysis, it reports the influence on the temporal transitions of the injection, depending on the spray characteristics, the effect of the ambient pressure, and the superheat level.

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