Influence of ammonium nitrate on the crystallisation of ammonium sulfate

This study aims to explore the influence mechanism of ammonium nitrate produced by ozone denitrification on the crystallisation of ammonium sulfate, a by-product of ammonia desulfurisation. The laser method was used to study the influence of ammonium nitrate on the solubility and metastable zone width of ammonium sulfate. An experiment on the influence of ammonium nitrate on the particle size of ammonium sulfate was designed, and the influence mechanism was explored through scanning electron microscopy and X-ray diffraction. The findings showed that the addition of ammonium nitrate increased the size and aspect ratio of ammonium sulfate crystals. The addition of ammonium nitrate inhibited the dissolution of ammonium sulfate and widened its metastable zone. The addition of ammonium nitrate covered the active sites of crystal nucleus growth, which inhibited the formation of crystal nuclei to a certain extent, and crystal growth dominated the crystallisation process. Moreover, the addition of ammonium nitrate induced the preferred orientation of the specific crystal plane of ammonium sulfate, and the addition of a small concentration of ammonium nitrate decreased the crystallinity of ammonium sulfate. The research results can provide a reference for crystallisation optimisation and quality improvement of ammonium sulfate in the ammonia desulfurisation process.

Modeling and simulation on spontaneous detonation of ammonium nitrate explosive induced by sulfide ores

In this work, the characteristics of the exothermic reaction between ammonium nitrate and sulfide ores were explored using COMSOL Multiphysics. This reaction can cause an increase in temperature within the blast holes of sulfide mines and can potentially induce premature explosions of the explosives. Initially, simulations were conducted to observe temperature variations in blast holes before and after the loading of explosives. Then, the impact of blast hole diameter and initial temperature on the thermal environment was assessed. Subsequent analysis focused on the fluid field's dynamics, examining flow rate changes and the concentration of signature gases produced by the reaction. Additionally, the influence of blast hole diameter on these parameters was evaluated. The results show that the blast hole temperature is positively related to its diameter and initial temperature. When the diameter of the blast hole is 120 mm and 165 mm, a significant change in flow rate is observed, with a trend of being rapidly increased and then rapidly decreased. The production of NH3 is always found to be greater than that of the other two gases. As for NO and SO2, their production is characterized by an approximate ratio of 1:2. The numerical simulation results can provide important theoretical guidance for the spontaneous detonation of blast hole in sulfide mines.

Nitrogen-fertilizer addition to an agricultural soil enhances biogenic non-extractable residue formation from 2-13C,15N-glyphosate

Glyphosate and nitrogen (N) or (P) phosphorus fertilizers are often applied in combination to agricultural fields. The additional P or N supply to microorganisms might drive glyphosate degradation towards sarcosine/glycine or aminomethylphosphonic acid (AMPA), and consequently determine the speciation of non-extractable residues (NERs): harmless biogenic NERs (bioNERs) or potentially hazardous xenobiotic NERs (xenoNERs). We therefore investigated the effect of P or N-fertilizers on microbial degradation of glyphosate and bioNER formation in an agricultural soil. Four different treatments were incubated at 20 °C for 75 days as follows; I: no fertilizer (2-13C,15N-glyphosate only, control), II: P-fertilizer (superphosphate + 2-13C,15N-glyphosate, effect of P-supply), III: N-fertilizer (ammonium nitrate + 2-13C,15N-glyphosate, effect of N-supply) and IV: 15N-fertilizer (15N-ammonium nitrate + 2-13C-glyphosate, differentiation between microbial assimilations of 15N: 15N-fertilizer versus 15N-glyphosate). We quantified 13C or 15N in mineralization, extractable residues, NERs and in amino acids (AAs). At the end, mineralization (36-41 % of the 13C), extractable 2-13C,15N-glyphosate/2-13C-glyphosate (0.42-0.49 %) & 15N-AMPA (1.2 %), and 13C/15N-NERs (40-43 % of the 13C, 40-50 % of the 15N) were comparable among treatments. Contrastingly, the 15N-NERs from 15N-fertlizer amounted to only 6.6 % of the 15N. Notably, N-fertilizer promoted an incorporation of 13C/15N from 2-13C,15N-glyphosate into AAs and thus the formation of 13C/15N-bioNERs. The 13C/15N-AAs were as follows: 16-21 % (N-fertilizer) > 11-13 % (control) > 7.2-7.3 % (P-fertilizer) of the initially added isotope. 2-13C,15N-glyphosate was degraded via the sarcosine/glycine and AMPA simultaneously in all treatments, regardless of the treatment type. The percentage share of bioNERs within the NERs in the N-fertilized soil was highest (13C: 80-82 %, 15N: 100 %) compared to 53 % (13C & 15N, control) and to only 30 % (13C & 15N, P-fertilizer). We thus concluded simultaneous N & glyphosate addition to soils could be beneficial for the environment due to the enhanced bioNER formation, while P & glyphosate application disadvantageous since it promoted xenoNER formation.

Role of WSOCs and pH on Ammonium Nitrate Aerosol Efflorescence: Insights into Secondary Aerosol Formation

Efflorescence of ammonium nitrate (AN) aerosols significantly impacts atmospheric secondary aerosol formation, climate, and human health. We investigated the effect of representative water-soluble organic compounds (WSOCs) (sucralose (SUC), glycerol (GLY), and citric acid (CA) on AN:WSOC aerosol efflorescence using vacuum Fourier transform infrared spectroscopy. Combining efflorescence relative humidity (ERH) measurements, heterogeneous nucleation rates, and model predictions, we found that aerosol viscosity, correlating with molecular diffusion, effectively predicted ERH variations among the AN:WSOC aerosols. WSOCs with higher viscosity (SUC and CA) hindered efflorescence, while GLY with a lower viscosity showed a minor effect. At a low AN:CA molar ratio (10:1), CA promoted ERH, likely due to CA crystallization. Increasing the droplet pH inhibited AN:CA aerosol efflorescence. In contrast, for AN:SUC and AN:GLY aerosols, efflorescence is pH-insensitive. With the addition of trivial sulfate, AN:SUC droplets exhibited two-stage efflorescence, coinciding with ammonium sulfate and AN efflorescence. Given the atmospheric abundance, the morphology, phase, and mixing state of nitrate aerosols are significant for atmospheric chemistry and physics. Our results suggest that AN:WSOCs aerosols can exist in the amorphous phase in the atmosphere, with efflorescence behavior depending on the aerosol composition, viscosity, pH, and the cation and anion interactions in a complex manner.

A practical method for predicting and analyzing the consequences of ammonium nitrate explosion accidents adjacent to densely populated areas

Several catastrophic ammonium nitrate (AN) explosion accidents have been reported during the last decades. Previous studies have been mainly focused on investigating adverse effects caused by the AN explosion, while only a few systematically analyzed the consequences and impacts of AN explosions. This study collects data from three typical AN explosions (accidental explosion of the US fertilizer plant in 2013; an accidental explosion of China's Tianjin port in 2015, and a recent explosion (2020) of the Beirut port in Lebanon). The consequences of accidental explosions were analyzed by mathematical equations that further provide scientific explanations for AN explosions. Based on the explosives' properties on-site, these accidental explosions were caused by condensed phase explosives. Comparison with the conditions at the explosion site indicated that blast overpressure was the primary factor in the loss of life and damage to the building, while ground shock was a secondary factor. The severity of loss of life and building damage from explosions decreased with increasing distance. These distances could be calculated by the scaling law, which was replaced by the equivalent TNT mass of the explosive and the damage scale's overpressure boundary value. In addition, mapping the damaged area on a map helped in the visual presentation of the consequence assessment. The long-term environmental and ecological impact due to the explosions was also an important issue that could not be ignored. Overall, this study establishes a simple and easy-to-use method to rapidly predict and assess the consequences of an explosion, and provides technical guidance for future emergency response to similar large-scale accidents.

Effect of incubation time of three single extraction procedures on trace element extraction from sediment and soil

The use of standard single-extraction procedures to evaluate the mobility and availability of trace elements is a common practice in most laboratories dealing with soil or sediment analysis. Most standard single-extraction procedures describe incubations last for 2 h. However, these were tested and validated for soil analysis. Applying them for sediment analysis without further investigation might be misleading and should be reviewed with care. This paper investigates the effect of incubation time on the extraction efficiency of three standard single-extracting reagents (0.01 M CaCl₂, 1 M NH₄NO₃, and 0.05 M EDTA). Incubation experiments with sediment and soil samples lasting for 2 h, 10 h, and 10 d were performed. The results indicated that 2 h appears sufficient to reach equilibrium using CaCl₂ or NH₄NO₃ for soil analysis; but when analyzing sediments, incubation for 10 d resulted in higher concentrations. Incubation experiments with 0.05 M EDTA showed that incubation for 2 h was enough to extract Cd from the soil sample, Mn and to a lesser extent Cd from the sediment samples; while for the other elements, incubation for 10 d yielded higher concentrations for both sample types compared to that obtained after 2 h and 10 h separately. Relative to the pseudo-total metal contents, more than 55% of all studied elements were extracted by using 0.05 M EDTA, indicating high bioavailable metal fraction.

Economic risk assessment of ammonium nitrate explosions at the Busan Port by determining the building damage using a 3D explosion simulation

Explosion-related disasters are large and difficult to predict; therefore, the magnitude of potential risks must be identified ahead of time. This paper presents a new method for evaluating economic risk based on building damage that can be carried out in advance. The study was conducted using scenario-based hazard analysis, vulnerability analysis, and risk assessment. Using the GIS (Geographic Information System) technique, spatial information of the damage target range was constructed, and the hazard analysis of the explosion accident was analyzed in connection with a three-dimensional explosion simulation. Vulnerability analysis based on impact was performed by reflecting building spatial information (location, material, and height), and economic risks caused by explosions in appropriate scenarios were confirmed by applying a new methodology that reflects the total area and building cost of 4708 building objects with an explosion radius of 3 km. The results revealed that the estimated damage costs of 44,616,934,076 won (∼3.60000 US dollars) and 584,230,849,444 won (∼476 million US dollars), respectively, provided the basis for policy decision-making for accident prevention. Using this study, the risk of explosion can be predicted in advance, and effective support for explosive storage buildings in terms of engineering, policy, and management is possible to minimize damage.

Interleaved NQR detection using atomic magnetometers

Interleaved Nuclear Quadrupole Resonance (NQR) detection was conducted on ammonium nitrate and potassium chlorate using two ⁸⁷Rb magnetometers, where potassium chlorate is measured during the T₁ limited recovery time of ammonium nitrate. The multi-pass magnetometers are rapidly matched to the NQR frequencies, 531 kHz and 423 kHz, with the use of a single tuning field. For ease of implementation, a double resonant tank circuit was used for excitation, but could be replaced by a broad-band transmitter. All work was done in an unshielded environment and compared to conventional coil detection. The two magnetometers were sensitive, base noise as low as 2 fT/Hz, and were shown to reduce ambient noise through signal subtraction. When an excitation pulse was introduced, however, residual ringing increased the noise floor; mitigation techniques are discussed. The two detection techniques resulted in comparable Signal-to-Noise Ratio (SNR). Interleaved detection using the atomic magnetometers took half the time of conventional detection and provided localization of the explosives.

Alleviation of iron deficiency in pear by ammonium nitrate and nitric oxide

BACKGROUND

Iron is essential for the growth and development of trace elements in plants, and iron deficiency can lead to leaf chlorosis. Ammonium and nitrate are the major forms of nitrogen present in soils. Ammonium nitrate alleviates the chlorosis of leaves caused by iron deficiency, but the mechanism is not clear in pear.

RESULTS

Ammonium nitrate induced the increase of nitric oxide (NO) under iron deficiency. We further analyzed the effect of NO by exogenous NO treatment. The results showed that ammonium nitrate and NO increased the activity of ferric chelate reductase. NO induced the expression of multiple IRT genes and promoted the transmembrane transport of irons. Ammonium nitrate and NO promoted the activity of nitrogen assimilation-related enzymes and the nitrogen absorption capacity, and they also increased glutamine synthetase activity. Finally, ammonium nitrate and NO increased chlorophyll synthesis, with subsequent increase in the photosynthetic capacity of plants and accumulation of biomass.

CONCLUSION

Ammonium nitrate indirectly alleviates the symptoms of plant yellowing by promoting the increase of NO, which increases the response of iron transporters. Both substances increase the nitrogen accumulation in plants. This study demonstrates a new option for minimizing Fe deficiency by regulating the balance between nutrients.

The Beirut Port Blast: spectrum of injuries and clinical outcomes at a large tertiary care center in Beirut, Lebanon

PURPOSE

To describe injuries and outcomes of casualties of Beirut Port Blast treated at a large tertiary care center in Beirut, Lebanon.

METHODS

A retrospective observational study assessing the spectrum of injuries, treatment, and medical outcome among casualties of the Beirut Port Blast, immediately after the blast and up to 1 week from the blast to the emergency department of the American University of Beirut Medical Center (AUBMC).

RESULTS

A total of 359 patients were included. Most (n = 343, 95.6%) were adults (> 19 years), and males (56%) with a mean age of 42 ± 20 years. The most frequent mechanism of injury was a penetrating injury (45.7%), followed by other blast-related injuries (30.4%), and blunt injuries (23.4%). The most affected anatomical location were the limbs. Most (n = 217, 60.4%) patients required imaging. The most frequently administered medication was analgesics (38%), followed by anesthetics (35%), antibiotics (31%), tetanus vaccine (31%), and fluids (28%). Blood and blood products were administered in 3.8% of cases. Emergent procedures included endotracheal intubation (n = 18, 5%), surgical airway (n = 3, 0.8%), chest tube insertion (n = 4, 1.1%), thoracotomy (n = 1, 0.3%), and CPR (n = 5, 1.4%). A quarter of patients required surgical operations in the operating room (n = 85, 23.6%) and 18% required noncritical care admissions, 5.3% required critical care admissions, and 2.8% were dead on arrival.

CONCLUSION

Casualties from this event had significant injuries requiring lifesaving interventions, surgical procedures, and admission to critical care units. High utilization of imaging modalities and of medications from existing stockpiles was also observed.

Effect of mineral fertilisers application on the transfer of natural radionuclides from soil to radish (Raphanus sativus L.)

Non-controlled usage of mineral fertilisers in agriculture land of Kazakhstan is a concerning issue, due to possible contamination of the soil by radionuclides. Pot experiment of growing of R. sativus with application of mineral fertilisers was carried out under natural conditions. Two commonly used mineral fertilisers, mono-potassium phosphate and ammonium nitrate, were chosen in the frame of current research to determine the impact of mineral fertiliser on transfer of natural radionuclides from soil to R. sativus edible part. For this goal, the activity concentrations of natural radionuclides U-234, U-238, Th-230, Th-232 and Ra-226, were determined in both R. sativus edible part and the investigated soil by using alpha-particle spectrometry. The highest activity concentrations were found for R. sativus edible part growing on soil that was fertilised by mono-potassium phosphate and were equal to 174 ± 17, 134 ± 15, 62 ± 4, 15 ± 2 and 2.8 ± 0.6 Bq/kg for U-234, U-238, Th-230, Th-232 and Ra-226, respectively. The results of soil-to- R. sativus edible part transfer factor for different radionuclides varied depending on the mineral fertiliser used. For evaluation of impact during consumption of R. sativus edible part by a population of Kazakhstan, annual effective ingestion dose and excess lifetime cancer risk were determined. The highest annual effective ingestion dose was found for R. sativus edible part cultivated in mono-potassium phosphate-fertilised soil and was equal to 4.4 μSv year^-1.

Ammonium nitrate explosion at the main port in Beirut (Lebanon) and air pollution: an analysis of the spatiotemporal distribution of nitrogen dioxide

An explosion of the ammonium nitrate (AN) stored at Beirut Port devastated the city on Tuesday 4 August 2020. Such an explosion produces pollutants such as nitrogen oxides (NO _x ). The most common NO _x is nitrogen dioxide (NO₂), which is present in the atmosphere due to natural and anthropogenic processes. The presence of NO₂ is used as indicator of air pollution. However, the specific contribution of NO₂ to air quality is uncertain due to the presence of other constituents, especially particulate matter (PM10). Research has shown that extended exposure to NO₂ may result in serious health effects. This study investigated the impact of the explosion on NO₂ levels in the atmosphere above Beirut and the surrounding area. NO₂ data from the Sentinel-5P program were used to map the levels of NO₂. Furthermore, ground-monitoring data were used to assess the levels of PM10 and ozone (O₃) due to the evident association between these constituents and NO₂. Results showed that NO₂ levels were higher than before the blast. However, 7 days after the explosion, NO₂ levels had returned to normal, while the levels of PM10 and O₃ remained normal following the explosion. However, a slight increase in the daily average atmospheric pressure was noticed after the explosion, which was attributed to the decomposition of ammonium nitrate.

Effects of long-term (70 years) nitrogen fertilization and liming on carbon storage in water-stable aggregates of a semi-arid grassland soil

Grasslands cover up to 40.5% of the world's landmass and store 30% terrestrial carbon (C). Various practices, including mineral fertilization and liming, are used to manage these ecosystems with potential long-term effects on the size and distribution of soil aggregates and inevitably carbon dynamics. The objective of this study was to examine the long-term effects of ^{nitrogen fertilization and liming on soil carbon storage and its dynamics in water-stable} aggregates of a semi-arid grassland. Soil samples (0-10 cm) were collected from Ukulinga long-term grassland trial in Pietermaritzburg, South Africa where nitrogen fertilizers have been applied annually and lime every five years for 70 years. Ten treatments were studied: the control (0 kgN/ha and unlimited), lime at 2250 kg/ha (L), ammonium sulphate at 70 kg/ha (AS70) and 211 kg/ha (AS211); ammonium nitrate at 70 kg/ha (AN70) and 211 kg/ha (AN211); AS70 + lime (AS70L); AS211 + lime (AS211L); AN70 + lime (AN70L) and AN211 + lime (AN211L). Nitrogen fertilizers significantly reduced soil pH and increased total soil N. Liming increased soil pH with no effect on total soil N. Lime and lime + N fertilizer treatments had no effect on mean weight diameter (MWD) while separate N application decreased MWD and large macro-aggregates (LMA). Lime only treatment had no effect on water stable aggregate (WSA) fractions. Nitrogen fertilization and liming (separately or in combination) did not affect total C concentration and stocks. Overall, soils had very high total soil organic carbon ranging from 49.7 - 57.6 g/kg across treatments. Nitrogen fertilization decreased organic carbon in LMA in AS70 (1.52%) and AN211 (1.67%) treatments compared to the control (3.40%) which was in concert with increases in C associated with small macro-aggregates (SMA) and micro-aggregates (MiA and SCA). Organic carbon in SMA was 2.67 % (AS70); AS211 (2.62 %); AN70 (2.02 %); AN211 (2.49 %) compared to 1.26 % in the control. Lime + N fertilizer treatments increased C storage in all aggregate fractions compared to N fertilizer only treatments. The lack of response in total SOC to 70 years of N fertilization and liming suggests possible C saturation given the high soil C concentration. Changes in C associated with WSA fractions suggests their importance as diagnostic indicators of N fertilization and liming induced changes in SOC. Findings also show that ammonium-based N fertilization is associated with soil acidification, dispersion of LMA resulting in an increase of microaggregates and C stored in them. Liming can counteracts acidifying and the dispersive effect on NH₄ ⁺ associated with ammonium-based fertilizers thus restoring macro-aggregation in N fertilized grasslands. These findings suggests that long-term N addition may result in poor soil physical condition and possible stabilization of C in stable fractions.

Purification of ammonium nitrate via recrystallization for isotopic profiling using isotope ratio mass spectrometry

Stable-isotope analysis of ammonium nitrate (AN) plays an important role for comparing and tracing the sources of AN samples. Numerous studies have reported the application of isotope ratio mass spectrometry (IRMS) for the stable-isotope analysis of AN. However, in real cases, AN is often mixed with liquid hydrocarbons, organic explosives, wood flour, and sodium chloride. Therefore, the purification of AN samples prior to IRMS analysis is essential. Based on the different solubilities of AN at different temperatures, AN samples were purified by recrystallization. The results show that recrystallization can effectively purify AN, and the isotope fractionation effect caused by recrystallization increases the stable-isotope ratio (δ¹⁵N increased by 0.07-0.14‰, δ¹⁸O increased by 0.15-0.33‰, and δ²H increased by 4.61-18.16‰). The change of δ¹⁵N and δ¹⁸O were close to the standard deviation values, and did not affect the differentiation of AN. δ²H was deemed unsuitable for AN differentiation, owing to isotopic exchange during recrystallization. Eight AN samples from different cities and four AN samples produced in different years and batches from the same manufacturer in China were analyzed after recrystallization. Both groups of AN samples could be distinguished by combining the nitrogen and oxygen isotope ratios. Therefore, recrystallization can be used as a means of AN purification for the accurate determination of AN in ammonium nitrate fuel oil and explosive residues.

Understanding phase transition and vibrational mode coupling in ammonium nitrate using 2D correlation Raman spectroscopy

Ammonium nitrate (AN) is an important component of the chemical industry such as an active ingredient in fertilizers, as an oxidizer in explosive compositions and propellants, and as a blasting agent in civil explosives. Numerous accidents have been reported in the past which concerns its thermal instability and poses a big threat to its processing, transportation, and storage. Despite much literature being reported to understand its thermal instability, a mechanistic view remains unclear. In the present work, we have studied the behavior of AN to temperature change using a mathematical approach called 2D correlation (2D Cos) Raman spectroscopy to provide complete insight into the detailed dynamical nature of the interactions between the species (ionic or molecular) occurring with an increase in temperature. We have analyzed various libration and translational modes of nitrate in the low-frequency region using this mathematical tool. It is observed from 2D maps that the phase transition of AN starts with changes in libration modes followed by various nitrate modes and ammonium modes which further precedes low-frequency translational modes. Further, the 2D correlation could differentiate between modes splitting and shifting based on specific 2D Cos pattern. The changes occurring in the N-O deformation modes, symmetric stretching modes as well as anti-symmetric stretching modes which have been attributed to the weakening of the hetero-ionic coupling between the NH₄⁺ and the NO₃^- ions could be clearly distinguished in the 2D synchronous and asynchronous plots. Besides, moving window analysis was performed to visualize the transition temperature at which phase change of AN takes place.

Ammonium nitrate is a risk for environment: A case study of Beirut (Lebanon) chemical explosion and the effects on environment

An attempt has been made in correspondence to explain the consequences of chemical pollution after the explosion of ammonium nitrate (AN) in Beirut (capital of Lebanon). The effects of chemicals in the air, soil, and water have been discussed. In addition, the study emphasizes on the research to restore the environment and enhanced safety measurements.

Ammonium nitrate regulated the color characteristic changes of pigments in Monascus purpureus M9

Monascus pigments (MPs) with different color characteristics, produced by submerged fermentation of Monascus purpureus M9, have potential application in food industry. In the present study, the effects and regulatory mechanisms of ammonium nitrate (AN) on the color characteristics of MPs were investigated. The concentration of intracellular pigments was significantly decreased when subjected to AN. The hue and lightness value indicated AN altered the total pigments appearance from original red to orange. The HPLC analysis for six major components of MPs showed that the production of rubropunctatin or monascorubrin, was significantly reduced to the undetectable level, whereas the yields of monascin, ankaflavin, rubropunctamine and monascorubramine, were apparently increased with AN supplement. To be noted, via real-time quantitative PCR strategy, the expression level of mppG, closely relative to orange pigments biosynthesis, was significantly down-regulated. However, the expression of mppE, involved in yellow pigments pathway, was up-regulated. Moreover, the broth pH value was dropped to 2.5–3.5 in the fermentation process resulted from AN treatment, along with the increased extracellular polysaccharide biosynthesis. Taken together, the change of MPs categories and amounts by AN might be the driving force for the color characteristics variation in M. purpureus M9. The present study provided useful data for producing MPs with different compositions and modified color characteristics.

The 1H T1 dispersion curve of fentanyl citrate to identify NQR parameters

We report the ¹H T₁ dispersion curve between 0 and 5 ​MHz for the synthetic opioid fentanyl citrate (C₂₈H₃₆N₂O₈). The structures in the curve can be used to estimate the ¹⁴N nuclear quadrupole resonance (NQR) frequencies of the material. Density functional theory predictions of the NQR parameters of several fentanyl citrate compounds are also reported. The predictions for the aniline nitrogen are consistent with structures in the observed T₁ data. To help interpret the fentanyl citrate results the T₁ dispersion curve for the explosive ammonium nitrate is also presented.

Direct conversion of NO and SO2 in flue gas into fertilizer using ammonia and ozone

This study focused on the simultaneous removal of NO and SO₂ from an industrial flue gas stream. To evaluate the removal efficiency of NO and SO₂ using O₃ and NH₃, the consumption of two reactants (O₃ and NH₃) in line with the conversion of NO and SO₂ was quantified experimentally. In addition, NO and SO₂ were converted to valuable fertilizers, NH₄NO₃ and (NH₄)₂SO₄. To identify a principle strategy to enhance the generation of fertilizer, Fourier transform infrared spectroscopy was used to examine the reaction mechanisms for the formation of NH₄NO₃ and (NH₄)₂SO₄. Acceleration of SO₂ oxidation could be achieved effectively by adding NO to a gas mixture of SO₂, NH₃, and O₃. The formation of HNO₃ might be enhanced by the simultaneous feeding of NO and SO₂. Particle generation was also 10 times higher for NH₃/(NO + SO₂) than for NH₃/NO and for NH₃/SO₂, which is a prominent feature of this study. Moreover, the introduction of steam had a positive influence on particle generation. This method offers dual applications for NO and SO₂ removal from a flue gas stream and direct fertilizer generation.

Inhalation of ammonium sulfate and ammonium nitrate adversely affect sperm function

Among the components of air pollution in developing countries and Asia, (NH₄)₂SO₄ and NH₄NO₃ are known as major water-soluble in-organic compounds that cause particulate matter. Several researchers have been reported that the (NH₄)₂SO₄ and NH₄NO₃ induce abnormal decreases in body weight, as well as pneumotoxic, and immunotoxic. Moreover, while it has been reported that (NH₄)₂SO₄ and NH₄NO₃ have detrimental effects on reproduction, specific effects on male fertility have not been addressed in depth. Therefore, the present study evaluated the reproductive toxicity of (NH₄)₂SO₄ and NH₄NO₃ in spermatozoa under the capacitation condition. Results showed that various sperm motion parameters were significantly altered after inhalation of (NH₄)₂SO₄ and NH₄NO₃. In particular, alterations to a range of motion kinematic parameters and to capacitation status were observed after capacitation. In addition, protein kinase A (PKA) activity and tyrosine phosphorylation were altered by (NH₄)₂SO₄ and NH₄NO₃ regardless of capacitation. Taken together, our results show that inhalation of (NH₄)₂SO₄ and NH₄NO₃ may induce adverse effects on male fertility such as sperm motility, motion kinematics, and capacitation status via unusual tyrosine phosphorylation by abnormal PKA activity. Therefore, we suggest that exposure to (NH₄)₂SO₄ and NH₄NO₃ should be highlighted as a health risk, as it may lead to male reproductive toxicity in humans and animals.

Significant restructuring and light absorption enhancement of black carbon particles by ammonium nitrate coating

Field observations have suggested that particulate nitrate can promote the aging of black carbon (BC), yet the mechanisms of the aging process and its impacts on BC's light absorption are undetermined. Here we performed laboratory simulation of internal mixing of flame-generated BC aggregates with ammonium nitrate. Variations in particle size, mass, coating thickness, effective density, dynamic shape factor, and optical properties were determined online by a suite of instruments. With the development of coatings, the particle size initially decreased until reaching a coating thickness of ∼10 nm and then started increasing, accompanied by an increase in effective density and a decrease in dynamic shape factor, reflecting the transformation of BC particles from highly fractal to near-spherical morphology. This is partially attributable to the restructuring of BC cores to more compact forms. Exposing coated particles to elevated relative humidity (RH) led to additional BC morphology changes, even after drying. Particle light absorption and scattering were also amplified with ammonium nitrate coating, increasing with coating thickness and RH. For BC particles with a 17.8 nm coating, absorption and scattering were increased by 1.5- and 7.9-fold when cycled through 70% RH (5-70-5% RH), respectively. The irreversible restructuring of the BC core caused by condensation of ammonium nitrate and water altered both absorption and scattering, with a magnitude comparable to or even exceeding the effects of increased coating. Results show that ammonium nitrate is among the most efficient coating materials with respect to modifying BC morphology and optical properties compared with other inorganic and organic species investigated previously. Accordingly, mitigation of nitrate aerosols is necessary for the benefits of both air pollution control and reducing the impacts of BC on visibility impairment and radiative forcing on climate change. Our results also pointed out that the effect of BC core restructuring needs to be considered when evaluating BC's light absorption enhancement.

Raman spectroscopy for detection of ammonium nitrate as an explosive precursor used in improvised explosive devices

Raman spectroscopy was evaluated as a sensor for detection of ammonium nitrate (NH₄NO₃, AN), fuel oil (FO), AN-water solutions, and AN- and FO-soil mixtures deposited on materials such as glass, synthetic fabric, cardboard and electrical tape to simulate field conditions of explosives detection. AN is an inorganic oxidizing salt that is commonly used in fertilizers and mining explosives, however, due to its widespread accessibility, AN-based explosives are also utilized for the manufacture of improvised explosive devices (IED). Pure AN crystals were ground to powder size and deposited on several substrates for Raman analysis, whereas FO was analysed in a quartz cuvette. To simulate field conditions samples of powdered AN, AN-water solutions (0.1% to 10.0% AN w/w), AN-soil (50% to 90% AN w/w) and FO-soil (50% to 75% FO w/w) were prepared and deposited on the clutter materials. Raman spectra were acquired at integration times between 0.1 and 30 s, and 3 replicate Raman measurements were carried out for each sample. The spectral window observed ranged from 300 to 3800 cm^-1. Several characteristic Raman bands were found, namely, at 710 cm^-1 (NO₃^-) and 1040 cm^-1 (NO₃^-) for AN; 1440-1470 cm^-1 (CH) and 2800-3000 cm^-1 (CH) for FO; 3000-3500 cm^-1 (OH) for water; and 615 cm^-1 (CCl), 1254 cm^-1 (CH), 1400 cm^-1 (CH₂) and 1600 cm^-1 (aromatic ring) for polyvinyl chloride (PVC, electrical tape). The effect of the AN concentration and integration time on the total and net Raman intensities, relative standard deviation, signal-to-noise ratio and relative limit of detection was evaluated. The relative limit of detection of AN in water was 0.1% (1 mg/g), and absolute limit of detection was 1.0 μg. The optimum integration time (≈10 s) for the Raman sensor to capture the analyte signals was estimated based on the Raman figures of merit as a function of the integration time.

Choice of mobile phase: Implications for size exclusion chromatography-inductively coupled plasma-mass spectrometry analyses of copper, zinc and iron metalloproteins

The correct identification of the metalloproteins present in human tissues and fluids is essential to our understanding of the cellular mechanisms underpinning a host of health disorders. Separation and analysis of biological samples are typically done via size exclusion chromatography hyphenated with inductively coupled plasma-mass spectrometry (SEC-ICP-MS). Although this technique can be extremely effective in identification of potential metalloproteins, the choice of mobile phase may have a marked effect on results, results by adversely affecting metal-protein bonds of the metalloproteins of interest. To assess the choice of mobile phase on SEC-ICP-MS resolution and the resulting metalloproteome pattern, we analysed several different sample types (brain homogenate; Cu/Zn-superoxide dismutase (SOD1); a molecular weight standard mix containing ferritin (Ft), ceruloplasmin (Cp), cytochrome c (CytC), vitamin B12 (B12) and thyroglobulin (Tg) using six different mobile phase conditions (200 mM, pH 7.5 solutions of ammonium salts nitrate, acetate, and sulfate; HEPES, MOPS and Tris-HCl). Our findings suggest that ammonium nitrate, ammonium acetate and Tris-HCl are optimal choices for the mobile phase, with the specific choice being dependent on both the number of samples and method of detection that is hyphenated with separation. Furthermore, we found that MOPS, HEPES and ammonium sulfate mobile phases all caused significant changes to peak resolution, retention time and overall profile shape. MOPS and HEPES, in particular, produced additional Fe peaks that were not detected with any of the other mobile phases that were investigated. As well as this, MOPS and HEPES both caused significant concentration dependent matrix suppression of the internal standard.

The self-sustaining decomposition of ammonium nitrate fertiliser: Case study, Escombreras valley, Spain

Fertilisers containing ammonium nitrate have caused several accidents over the years, including toxic clouds, fires and explosions. For this reason, this work examines the accident that occurred in Escombreras valley (Cartagena, Spain) related to the decomposition of NPK 15-15-15 fertiliser, composed basically of monoammonium phosphate, ammonium nitrate and potassium chloride. The fertiliser was stored in a silo and its decomposition produced a toxic cloud formed of nitrogen oxides. Calculations have been made to determine the amount of heat released in the accident and the temperature gradient in the stored pile. The causes of the accident are not clear but could be related to the presence of decomposing organic matter. Fault tree analysis has revealed several weak points in the storage conditions. The dispersion of the gases produced has been simulated to evaluate the distance that dangerous concentrations of gases would reach. Almost 4000 people suffered the consequences of the accident, although most of them experienced only minor irritations and episodes of confinement due to their proximity to the site. To conclude, a series of lessons have been extracted that can help avoid similar accidents in the future.

Experimental study of the effect of typical halides on pyrolysis of ammonium nitrate using model reconstruction

The energetic material ammonium nitrate (AN) is used as an industrial raw material; however, it presents a pyrolysis and explosion hazard during transportation and storage, especially when mixed with impurities. To study the effects of typical halides on the thermal decomposition kinetics of AN, a series of precision thermogravimetric analysis experiments at four heating rates were carried out in a nitrogen atmosphere. Based on derivative thermogravimetric analysis, the addition of sodium halides was found to change the kinetic reaction mechanism of AN pyrolysis. The activation energies were obtained using the isoconversional method, and the pre-exponential factor was derived from the kinetic compensation effect. Models of the kinetic reaction mechanism were reliably reconstructed by combining composite kinetic data processing methods, namely, model-free method, model-fitting method, and parameter simulation. A comprehensive analysis showed that the addition of sodium halides shifts the kinetic mechanism of the pyrolysis of AN toward different dominant reaction models (such as reaction order models, power law models, or phase boundary control models) than those of the original reaction model. The results are helpful as a reference and provide guidance for the determination of AN pyrolysis behavior and the simulation of parameters.

Nitrous oxide emission factors of mineral fertilisers in the UK and Ireland: A Bayesian analysis of 20 years of experimental data

In this study, we analysed datasets of N₂O emission factors (EFs) from 21 separate studies carried out on arable and managed grasslands across the UK and Ireland over the past 20 years. A total of 641 separate events were collated from 40 experimental field sites. Individual EFs ranged over an order of magnitude (0-12% of applied N) for each fertiliser type, following a log-normal distribution in all cases. Our study shows that a Bayesian approach can provide a robust statistical method that is capable of performing uncertainty analysis on log-normal distributed data in a more defensible manner than conventional statistical methods allow. This method allowed for a national scale comparison of EFs between the most commonly applied mineral fertilisers based solely on previously published data (UK and Ireland in this case). The study shows that ammonium nitrate (AN) and Calcium ammonium nitrate (CAN) are the largest emitting fertiliser types by mass across the British Isles (temperate climate zone), with EFs of 1.1 (1.0-1.2) % and 1.0 (0.7-1.3) % for all recorded events, respectively; however, emissions from AN applications were significantly lower for applications to arable fields (0.6%) than to grasslands (1.3%). EFs associated with urea (CO(NH₂)₂) were significantly lower than AN for grasslands with an EF of 0.6 (0.5-0.7) %, but slightly higher for arable fields with an EF of 0.7 (0.4-1.4) %. The study highlights the potential effectiveness of microbial inhibitors at reducing emissions of N₂O from mineral fertilisers, with Dicyandiamide (DCD) treated AN reducing emissions by approximately 28% and urea treated with either DCD or N-(n)-butyl) thiophosphorictriamide (NBTP) reducing emissions by approximately 40%. Although limited by a relatively small sample size (n = 11), urea treated with both DCD and NBPT appeared to have the lowest EF of all treatments at 0.13 (0.08-0.21) %, highlighting the potential to significantly reduce N₂O emissions at regional scales if applied instead of conventional nitrogen fertilisers.

Evaluation of subchronic repeated administration toxicity of ammonium nitrate in rats

Ammonium nitrate is a chemical mostly used in agriculture and munitions to produce fertilizers and explosives, respectively. Its annual production and consumption exceed ten million tons. Despite is diverse uses, large production and consumption, and occupational risk, information on the toxicity that results from oral exposure to ammonium nitrate is limited. In this study, the safety of ammonium nitrate was therefore evaluated by observing its subchronic toxicity in rats. Ammonium nitrate (0, 100, 300 and 1000 mg/kg/day) was orally administered by gavage to rats at 5 times/week for 13 weeks. Reversibility of the effects of 1000 mg/kg/day was assessed in rats after 2 weeks. Mortality, clinical signs, body weight, and food consumption were monitored. Hematology, serum chemistry, urinalysis, organ weight, necropsy, and histopathology were performed. Salivation was intermittently observed in both sexes receiving 300 and 1000 mg/kg/day ammonium nitrate, which normalized 2 weeks post-treatment. Urine volume increased in both sexes receiving 1000 mg/kg/day ammonium nitrate. Urine pH decreased in both sexes of all dosing groups when compared with the concurrent control group. Urinary changes normalized 2 weeks post-treatment. Blood urea nitrogen levels increased in males receiving 1000 mg/kg/day, but normalized 2 weeks later. Potassium level in males and sodium and chloride levels in both sexes receiving 1000 mg/kg/day ammonium nitrate decreased, but normalized 2 weeks later. Hypertrophy of zona glomerulosa in the adrenals was observed in both sexes receiving 1000 mg/kg/day and in females receiving 300 mg/kg/day ammonium nitrate. After a 2-week recovery period, the same lesion was observed in one female receiving 1000 mg/kg/day ammonium nitrate. Our results indicate that ammonium nitrate induces reversible salivation, increases BUN levels, induces acidic diuresis with decreases in sodium, potassium, and chloride levels, and induces ZG hypertrophy. These results shed light on the toxicity profile of ammonium nitrate.

Mechanism study of ammonium nitrate decomposition with chloride impurity using experimental and molecular simulation approach

Fire/explosion due to ammonium nitrate (AN) decomposition poses significant safety hazards which are exacerbated in the presence of salts including potassium chloride (KCl). In this work, key thermal parameters of AN decomposition over a range of KCl mass fraction were experimentally measured using advanced reactive chemical screening tool (ARSST). Based on experimental findings and past literature review, AN/KCl decomposition mechanism was proposed consisting of four separate pathways, specifically, (i) direct AN main decomposition pathway, (ii) indirect AN main decomposition pathway via chlorine radical, (iii) direct pure AN side decomposition pathway and (iv) indirect AN side decomposition pathway via chlorine radical. Gaussian software was used to estimate activation energies for each reaction step involved in the proposed mechanism via density function theory (DFT). The computational chemistry model explained experimental data with good agreement. Both computational and experimental findings confirm that chlorine radical reduce reaction barrier of AN decomposition via indirect pathways (ii) and (iv). As these indirect decomposition pathways are more exothermic than the primary paths (i), (iii), KCl addition not only accelerates AN decomposition but also increases reaction heat release.

Divine's CO2 Absorber of 1867

Chemist and inventor Silas R. Divine (1838-1912) sold ammonium nitrate and other anesthesia supplies in New York City. He offered a carbon dioxide absorber for the purpose of rebreathing nitrous oxide. Like his colleague Gardner Q. Colton, he denied the need for nitrous oxide to be supplemented with O₂ gas.

Spectral descriptors and supervised classifier for ammonium nitrate detection in landmines by nuclear quadrupole resonance

The high specificity of Nuclear Quadrupole Resonance (NQR) makes it very suited for the detection of antipersonnel mines, where the intensity of the signal spectrum around the resonance frequency of the target substance is the standard decision parameter; however, radiofrequency interference, soil effects on the search coil, landmine size, burial depth, and target temperature affect signal intensity. To overcome this, the use of spectral descriptors and a supervised classifier are proposed in this work, where an assembly of decision trees was trained with NQR data collected on places where a target filled with ammonium nitrate was present and where it was not. A statistical test, comparing the proposed classifier and the solution based solely on the intensity of the signal spectrum, showed with significant evidence that the proposed classifier outperforms the traditional solution. A final blind experiment was conducted in a rural region of Colombia, where five landmines of different size filled with ammonium nitrate were shallowly buried in an area of 1.9 × 1.52 m, and the system with the proposed classifier detected four of them with three false alarms. This work is also novel in detecting ammonium nitrate in antipersonnel mines, which are typical in Colombia, the second most mined country in the world.

Production and performance of bio-based mineral fertilizers from agricultural waste using ammonia (stripping-)scrubbing technology

Development and optimization of nutrient recovery technologies for agricultural waste is on the rise. The full scale adoption of these technologies is however hindered by complex legal aspects that result from lack of science-based knowledge on characterization and fertilizer performance of recovered end-products. Ammonium sulfate (AS) and ammonium nitrate (AN), end-products of (stripping-)scrubbing technology, are currently listed by the European Commission as high priority products with the potential of replacing synthetic N fertilizers. The legal acceptance of AS and AN will be highly dependent on critical mass of scientific evidence. This study describes four different (stripping-)scrubbing pathways to recover ammonia with an aim to (i) assess product characteristics of ammonium nitrate (AN) and ammonium sulfate (AS) produced from different installations, (ii) evaluate fertilizer performance of recovered end-products in greenhouse (Lactuca sativa L.) and full field (Zea mays L.) scale settings and (iii) compare the observed performances with other published studies. Results have indicated that the recovered products might have a different legal status, as either mineral N fertilizer or yet as animal manure, depending on the used (stripping-)scrubbing process pathway. Nevertheless, no significant differences in respect to product characterization and fertilizer performance of AN and AS have been identified in this study as compared to the conventional use of synthetic N fertilizers. This indicates that recovered AS and AN are valuable N sources and therefore might be used as N fertilizers in crop cultivation.

An experimental and theoretical study of optimized selection and model reconstruction for ammonium nitrate pyrolysis

Ammonium nitrate (AN) is a commonly-used industrial raw material in industrial explosives and fertilizers areas. However, as an energetic material, its danger exists during the production, transportation, and storage, resulting in a large number of accidents involving personal injury and property loss. To obtain the accurate kinetic triplet parameters of AN thermal decomposition, a series of thermogravimetry analysis (TGA) experiments was conducted with four different heating rates. Activation energies were calculated by different isoconversional methods Then the kinetic triplet of AN pyrolysis was optimized using a combination of experimental and simulant methods. Combined with the traditional model-free and model-fitting approaches, the experimental kinetic model for AN pyrolysis was optimized and then reconstructed. Through the pyrolysis reaction of AN, a reliable methodology for processing TGA data of hazardous material is proposed in the paper, and the kinetic parameters can be accurately obtained by using such a kinetics method.

Assessing the fate of explosives derived nitrate in mine waste rock dumps using the stable isotopes of oxygen and nitrogen

Ammonium nitrate (NH₄NO₃) mixed with fuel oil is a common blasting agent used to fragment rock into workable size fractions at mines throughout the world. The decomposition and oxidation of undetonated explosives can result in high NO₃^- concentrations in waters emanating from waste rock dumps. We used the stable isotopic composition of NO₃^- (δ¹⁵N- and δ¹⁸O-NO₃^-) to define and quantify the controls on NO₃^- composition in waste rock dumps by studying water-unsaturated and saturated conditions at nine coal waste rock dumps located in the Elk Valley, British Columbia, Canada. Estimates of the extent of nitrification of NH₄NO₃ in oxic zones in the dumps, initial NO₃^- concentrations prior to denitrification, and the extent of NO₃^- removal by denitrification in sub-oxic to anoxic zones are provided. δ¹⁵N data from unsaturated waste rock dumps confirm NO₃^- is derived from blasting. δ¹⁵N- and δ¹⁸O-NO₃^- data show extensive denitrification can occur in saturated waste rock and in localized zones of elevated water saturation and low oxygen concentrations in unsaturated waste rock. At the mine dump scale, the extent of denitrification in the unsaturated waste rock was inferred from water samples collected from underlying rock drains.

Efficient mercury removal from wastewater by pistachio wood wastes-derived activated carbon prepared by chemical activation using a novel activating agent

Ammonium nitrate (NH₄NO₃) with explosive characteristics at high temperatures was used as a novel activating reagent to prepare a surface-engineered activated carbon derived from pistachio wood wastes (PWAC). PWAC was characterized and compared with commercial activated carbon (CAC) by textural and morphological properties, surface chemistry, crystal structure, and surface elemental composition. The results indicated that the optimal conditions of PWAC preparation to obtain the highest mercury adsorption capacity were pyrolysis temperature (800 °C), pyrolysis time (2 h), and impregnation ratio (5%). PWAC was of highly regular-shaped and well-developed pores and possessed a large surface area (1448 m²/g) and high total pore volume (0.901 cm³/g). The batch experiments indicated that the adsorption process of Hg(II) was strongly dependent on the solution pH and reached fast equilibrium at approximately 30 min. PWAC (202 mg/g) exhibited a significantly higher maximum adsorption capacity than commercial activated carbon (66.5 mg/g). Adsorbent-adsorbate dispersion interaction plays a major role in the adsorption mechanism, compared to the minor role played by pore filling and reduction mechanism. Overall, ammonium nitrate can be considered a newer activating reagent to prepare promising and low-cost PWAC for effectively Hg(II) removal from water media.

Medium composition potentially regulates the anthocyanin production from suspension culture of Daucus carota

In the present study, an effort has been made to optimize various culture conditions for enhanced production of anthocyanin. Nutrient content of MS medium (ammonium to potassium nitrate ratio and phosphate concentration) had a profound influence on the cell biomass and anthocyanin accumulation in cell suspension cultures of Daucus carota. Suspension cultures were carried out in shake flasks for 18 days and examined for cell growth, anthocyanin synthesis, anthocyanin yield and development of pigmented cells in relation to the uptake of total sugar, extracellular phosphate, nitrate and ammonia. The addition of NH4NO3 to KNO3 ratio (20.0 mM: 37.6 mM) in the suspension culture media resulted in a 2.85-fold increase in anthocyanin content at day 3. Similarly, a lower concentration of KH2PO4 (0.45 mM) in the MS medium resulted in 1.63-fold increase in anthocyanin content at day 9. The total sugar uptake was closely associated with a significant increase in anthocyanin accumulation. Total sugar and nitrate were consumed until 9-12 days, while ammonia and phosphate were completely consumed within 3 days after inoculation. After 9 days, cell lysis was observed and resulted in the leakage of intracellular substances. These observations suggest that anthocyanin was synthesized only by viable pigmented cells and degraded rapidly after cell death and lysis. This study signifies the utility of D. carota suspension culture for further up-scaling studies of anthocyanin.

Study by Monte Carlo methods of an explosives detection system made up with a D-D neutron generator and NaI(Tl) gamma detectors

Detection of hidden explosives is of utmost importance for homeland security. Several configurations of an Explosives Detection System (EDS) to intercept hidden threats, made up with a Deuterium-Deuterium (D-D) compact neutron generator and NaI (Tl) scintillation detectors, have been evaluated using MCNP6 code. The system's response to various samples of explosives, such as RDX and Ammonium Nitrate, is analysed. The D-D generator is able to produce fast neutrons with 2.5 MeV energy in a maximum yield of 10¹⁰ n/s. It is surrounded by high-density polyethylene to thermalize the fast neutrons and to optimize interactions with the sample inspected, whose emission of gamma rays gives a characteristic spectrum of the elements that constitute it. This procedure allows to determine its chemical composition and to identify the type of substance. The necessary shielding is evaluated to estimate its thicknesses depending on the admissible dose of operation, using lead and polyethylene. The results show that its functionality is promising in the field of national security for explosives inspection.

Optimization of submerged fermentation medium for citrinin-free monascin production by Monascus

Microbial fermentation of citrinin-free Monascus pigments is in favor in the development of food industry. This study investigated the influences of carbon source, nitrogen source, and mineral salts on the cell growth, monascin (MS), and citrinin (CT) production in Monascus M9. A culture medium composition was established for maximizing the production of citrinin-free MS in submerged culture, as follows: 50 g/L Japonica rice powder, 20 g/L NH₄NO₃, 3 g/L NaNO₃, 1.5 g/L KH₂PO₄, 1 g/L MgSO₄ · 7H₂O, 0.2 g/L MnSO₄. Under these conditions, no CT was detectable by high performance liquid chromatography. The yield of MS reached 14.11 mg/g, improving approximately 30% compared with before optimization.

Impact of ammonium nitrate and sodium nitrate on tadpoles of Alytes obstetricans

The presence of pesticides, herbicides and fertilisers negatively affect aquatic communities in general, and particularly amphibians in their larval phase, even though sensitivity to pollutants is highly variable among species. The Llobregat Delta (Barcelona, Spain) has experienced a decline of amphibian populations, possibly related to the reduction in water quality due to the high levels of farming activity, but also to habitat loss and alteration. We studied the effects of increasing ammonium nitrate and sodium nitrate levels on the survival and growth rate of Alytes obstetricans tadpoles under experimental conditions. We exposed larvae to increasing concentrations of nitrate and ammonium for 14 days and then exposed them to water without pollutants for a further 14 days. Only the higher concentrations of ammonium (>33.75 mg/L) caused larval mortality. The growth rate of larvae was reduced at ≥22.5 mg/L NH₄⁺, although individuals recovered and even increased their growth rate once exposure to the pollutant ended. The effect of nitrate on growth rate was detected at ≥80 mg/L concentrations, and the growth rate reduction in tadpoles was even observed during the post-exposure phase. The concentrations of ammonium with adverse effects on larvae are within the range levels found in the study area, while the nitrate concentrations with some adverse effect are close to the upper range limit of current concentrations in the study area. Therefore, only the presence of ammonium in the study area is likely to be considered of concern for the population of this species, even though the presence of nitrate could cause some sublethal effects. These negative effects could have an impact on population dynamics, which in this species is highly sensitive to larval mortality due to its small clutch size and prolonged larval period compared to other anuran amphibians.

Solid polymer electrolyte production from 2-hydroxyethyl cellulose: Effect of ammonium nitrate composition on its structural properties

Addition of doping materials can possibly enhance the ionic conduction of solid polymer electrolyte (SPE). In this work, a new SPE using 2-hydroxyethyl cellulose (2-HEC) incorporated with different ammonium nitrate (NH₄NO₃) composition was prepared via solution casting method. Studies of structural properties were conducted to correlate the ionic conductivity of 2-HECNH₄NO₃ SPE using X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy. Encouraging result was obtained as the ionic conductivity increased about two orders of magnitude upon addition of 12wt% of NH₄NO₃. XRD analysis shows the most amorphous SPE was obtained at 12-NH₄NO₃. From FTIR spectra, the interactions between 2-HEC and NH₄NO₃ were observed by the shifts of COH peak from 1355cm^-1 to 1330cm^-1 and the presence of new NH peak in the OH region. The spectrum has been validated theoretically using Gaussian software. The results obtained from this study corroborate that the complexes of 2-HEC and NH₄NO₃ responsible to promote the ionic conductivity to the higher value.

Controlling Hyperhydricity in Date Palm In Vitro Culture by Reduced Concentration of Nitrate Nutrients

Hyperhydricity (or vitrification) is a fundamental physiological disorder in date palm micropropagation. Several factors have been ascribed as being responsible for hyperhydricity, which are related to the explant, medium, culture vessel, and environment. The optimization of inorganic nutrients in the culture medium improves in vitro growth and morphogenesis, in addition to controlling hyperhydricity. This chapter describes a protocol for controlling hyperhydricity during the embryogenic callus stage by optimizing the ratio of nitrogen salts of the Murashige and Skoog (MS) nutrient culture medium. The best results of differentiation from cured hyperhydric callus are obtained using modification at a ratio of NH⁴⁺/NO^3- at 10:15 (825:1425 mg/L) of the MS culture medium to remedy hyperhydric date palm callus and achieve the recovery of normal embryogenic callus and subsequent regeneration of plantlets. Based on the results of this study, nutrient medium composition has an important role in avoiding hyperhydricity problems during date palm micropropagation.

Case study and lessons learned from the ammonium nitrate explosion at the West Fertilizer facility

In West, Texas on April 17, 2013, a chemical storage and distribution facility caught fire followed by the explosion of around 30 tons of ammonium nitrate while the emergency responders were trying to extinguish the fire, leading to 15 fatalities and numerous buildings, businesses and homes destroyed or damaged. This incident resulted in devastating consequences for the community around the facility, and shed light on a need to improve the safety management of local small businesses similar to the West facility. As no official report on the findings of the incident has been released yet, this article first investigates the root causes of the incident, and presents a simplified consequence analysis. The article reviews the regulations applicable to this type of facility and recommended emergency response procedures to identify gaps between what happened in West and the current regulations, and discusses how the current regulations could be modified to prevent or minimize future losses. Finally, the federal response that followed the incident until the publication of this paper is summarized.

Explosions of ammonium nitrate fertilizer in storage or transportation are preventable accidents

Ammonium nitrate (AN) is a detonable substance which has led to numerous disasters throughout the 20th century and until the present day, with the latest disaster occurring on 17 April 2013. Needed safety lesson have not been learned, since typically each accident was viewed as a great surprise and investigations focused on finding some unique reason for the accident, rather than examining what is common among the accidents. A review is made of accidents which involved AN for fertilizer purposes, and excluding incidents involving ANFO or additional explosives apart from AN. It is found that, for explosions in storage or transportation, 100% of these disasters had a single causative factor-an uncontrollable fire. Thus, such disasters can be eliminated by eliminating the potential for uncontrolled fire. Two actions are required to achieve this: (1) adoption of fertilizer formulations which reduce the potential for uncontrolled fire and for detonation; and (2) adoption of building safety measures which provide assurance against uncontrolled fires. Technical means are available for achieving both these required measures. These measures have been known for a long time and the only reason that disasters continue to occur is that these safety measures are not implemented. The problem can be solved unilaterally by product manufacturers or by government authorities, but preferably both should take necessary steps.

Low levels of chemical anthropogenic pollution may threaten amphibians by impairing predator recognition

Recent studies suggest that direct mortality and physiological effects caused by pollutants are major contributing factors to global amphibian decline. However, even sublethal concentrations of pollutants could be harmful if they combined with other factors to cause high mortality in amphibians. Here we show that sublethal concentrations of pollutants can disrupt the ability of amphibian larvae to recognize predators, hence increasing their risk of predation. This effect is indeed much more important since very low amounts of pollutants are ubiquitous, and environmental efforts are mostly directed towards preventing lethal spills. We analyzed the effects of two common contaminants (humic acid and ammonium nitrate) on the ability of tadpoles of the western spadefoot toad (Pelobates cultripes) to recognize chemical cues from a common predator, nymphs of the dragonfly Anax imperator. We compared the swimming activity of tadpoles in the presence and absence of water-borne chemical cues from dragonflies at different concentrations of humic acid and ammonium nitrate. Tadpoles reduced swimming activity in response to predator cues in the absence of pollutants, whereas they remained unresponsive to these cues when either humic acid or ammonium nitrate was added to the water, even at low concentrations. Moreover, changes in tadpole activity associated with the pollutants themselves were non-significant, indicating no toxic effect. Alteration of the natural chemical environment of aquatic systems by pollutants may be an important contributing cause for declines in amphibian populations, even at sublethal concentrations.

Novel electrostatic precipitator using unipolar soft X-ray charger for removing fine particles: Application to a dry de-NOX process

The novel electrostatic precipitator (ESP), consisting of a soft X-ray charger and a collection part, was demonstrated and applied to a dry de-NOX process to evaluate its performance in by-product particle removal. NOX gas was oxidized by ozone (O3) and neutralized by ammonia (NH3) sequentially, and finally converted to an ammonium nitrate (NH4NO3) aerosol with ∼ 100-nm peak particle diameter. The unipolar soft X-ray charger was introduced for charging the by-product particles in this dry de-NOX process. For the highest particle collection efficiency, the optimal operating conditions of the soft X-ray charger and collection part were investigated by adjusting the applied voltage of each device. The results showed that ∼ 99% of NOX was removed when the O3/NOX ratio was increased to 2 (i.e., the maximum production conditions of the NH4NO3 by-product particles by the gas-to-particle conversion process). The highest removal efficiency of particle (∼ 90%) was observed with operating conditions of positive polarity and an applied voltage of ∼ 2-3 kV in the charger chamber. The unipolar soft X-ray charger has potential for particle removal systems in industrial settings because of its compact size, ease of operation, and non-interruptive charging mechanism.

Isotopic and elemental profiling of ammonium nitrate in forensic explosives investigations

Ammonium nitrate (AN) is frequently encountered in explosives in forensic casework. It is widely available as fertilizer and easy to implement in explosive devices, for example by mixing it with a fuel. Forensic profiling methods to determine whether material found on a crime scene and material retrieved from a suspect arise from the same source are becoming increasingly important. In this work, we have explored the possibility of using isotopic and elemental profiling to discriminate between different batches of AN. Variations within a production batch, between different batches from the same manufacturer, and between batches from different manufacturers were studied using a total of 103 samples from 19 different fertilizer manufacturers. Isotope-ratio mass spectrometry (IRMS) was used to analyze AN samples for their (15)N and (18)O isotopic composition. The trace-elemental composition of these samples was studied using inductively coupled plasma-mass spectrometry (ICP-MS). All samples were analyzed for the occurrence of 66 elements. 32 of these elements were useful for the differentiation of AN samples. These include magnesium (Mg), calcium (Ca), iron (Fe) and strontium (Sr). Samples with a similar elemental profile may be differentiated based on their isotopic composition. Linear discriminant analysis (LDA) was used to calculate likelihood ratios and demonstrated the power of combining elemental and isotopic profiling for discrimination between different sources of AN.

Polarization enhancement technique for nuclear quadrupole resonance detection

We demonstrate a dramatic increase in the signal-to-noise ratio (SNR) of a nuclear quadrupole resonance (NQR) signal by using a polarization enhancement technique. By first applying a static magnetic field to pre-polarize one spin subsystem of a material, and then allowing that net polarization to be transferred to the quadrupole subsystem, we increased the SNR of a sample of ammonium nitrate by one-order of magnitude.

Environmental analysis of sunflower production with different forms of mineral nitrogen fertilizers

Environmental profiles of mineral nitrogen fertilizers were used to evaluate the environmental disturbances related to their use in cultivation systems in Europe. Since the production of mineral fertilizers requires a large amount of energy, the present study of bioenergy systems is relevant in order to achieve crop yields less dependent on fossil fuels and to reduce the environmental impact due to fertilization. In this study, the suitability of the LCA methodology to analyze the environmental impact of sunflower cultivation systems with different forms of mineral nitrogen fertilizers urea and ammonium nitrate was investigated. Effects on climate change were estimated by the use of Ecoinvent 2.2 database default value for soil N2O emission factor (1%) and local emission data (0.8%) of mineral nitrogen applied to soils. LCA analysis showed a higher impact on environmental categories (human health and ecosystem quality) for the system in which urea was used as a nitrogen source. Use of urea fertilizer showed a higher impact on resource consumption due to fossil fuel consumption. Use of mineral nitrogen fertilizers showed a higher environmental burden than other inputs required for sunflower cultivation systems under study. Urea and ammonium nitrate showed, respectively, a 7.8% and 4.9% reduced impact of N2O as greenhouse gas by using direct field data of soil N2O emission factor compared to the default soil emission factor of 2006 IPCC Guidelines. Use of ammonium nitrate as mineral nitrogen fertilizer in sunflower cultivation would have a lower impact on environmental categories considered. Further environmental analysis of available technologies for fertilizer production might be also evaluated in order to reduce the environmental impacts of each fertilizer.

Glyphosate detection with ammonium nitrate and humic acids as potential interfering substances by pulsed voltammetry technique

Pulsed voltammetry has been used to detect and quantify glyphosate on buffered water in presence of ammonium nitrate and humic substances. Glyphosate is the most widely used herbicide active ingredient in the world. It is a non-selective broad spectrum herbicide but some of its health and environmental effects are still being discussed. Nowadays, glyphosate pollution in water is being monitored but quantification techniques are slow and expensive. Glyphosate wastes are often detected in countryside water bodies where organic substances and fertilizers (commonly based on ammonium nitrate) may also be present. Glyphosate also forms complexes with humic acids so these compounds have also been taken into consideration. The objective of this research is to study the interference of these common pollutants in glyphosate measurements by pulsed voltammetry. The statistical treatment of the voltammetric data obtained lets us discriminate glyphosate from the other studied compounds and a mathematical model has been built to quantify glyphosate concentrations in a buffer despite the presence of humic substances and ammonium nitrate. In this model, the coefficient of determination (R(2)) is 0.977 and the RMSEP value is 2.96 × 10(-5) so the model is considered statistically valid.

Evaluation of the Genetic Toxicity of Cyclopentane and Ammonium Nitrate - In vitro Mammalian Chromosomal Aberration Assay in Chinese Hamster Ovary Cells

Objectives

In this study, the in vitro mammalian chromosomal aberration (CA) assay was conducted to gain additional information concerning the hazards associated with the use of cyclopentane and ammonium nitrate. While these two chemicals had already been tested by many methods, they had not been studied in the CA test.

Methods

The assay was performed using the ovarian infantile cell (CHO-K1 cell), by the direct method (-S9) and by the metabolic activated method (+S9 mix).

Results

Using the direct method, the 7 dosages in a 48 hour treatment group did not show that the frequency of CA is proportion to the dosage addition. The frequency of CA is not proportion to the dosage addition for a 6 hour treatment using the metabolic activated method.

Conclusion

From these findings, it was decided that the 2 chemicals do not induce chromosomal aberrations under the tested conditions.