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Due to the current global energy shortage and increasingly serious environmental issues, green propellants are attracting more attention. In particular, the ammonium dinitramide (ADN)-based monopropellant thruster is gaining world-wide attention as a green, non-polluting and high specific impulse propellant. Gel propellants combine the advantages of liquid and solid propellants, and are becoming popular in the field of spaceflight. In this paper, a swirling atomization experimental study was carried out using an ADN aqueous gel propellant under different injection pressures. A high-speed camera and a Malvern laser particle size analyzer were used to study the spray process. The flow coefficient, cone angle of swirl atomizing spray, breakup length of spray membrane, and droplet size distribution were analyzed. Furthermore, the effects of different injection pressures on the swirling atomization characteristics were studied. [ABSTRACT FROM AUTHOR]

In this paper, an improved spectrofluorimetric method for the simultaneous and direct determination of ammonium and primary amine compounds is presented. The method is based on the derivatization of the analytes with o -phthaldialdehyde (OPA)/ N -acetylcysteine (NAC) reagent using high throughput microplates, and OPA/NAC ratio has been optimized in order to suppress interference of ammonium on primary amine determination. Direct measurement of these two parameters is therefore possible with a global procedure time that does not exceed 10 min. Excellent limits of detection of 1.32 μM and 0.55 μM have been achieved for ammonium and primary amines, respectively. Reagent stability issues have also been addressed and formulation of reagents solution is described for improved reagents shelf life. The proposed protocol was finally applied and validated on real samples such as wine samples, compost extracts and wastewater. [ABSTRACT FROM AUTHOR]

We compute the ion/water interaction energies of methylated ammonium cations and alkylated carboxylate anions solvated in large nanodroplets of 10 000 water molecules using 10 ns molecular dynamics simulations and an all-atom polarizable force-field approach. Together with our earlier results concerning the solvation of these organic ions in nanodroplets whose molecular sizes range from 50 to 1000, these new data allow us to discuss the reliability of extrapolating absolute single-ion bulk solvation energies from small ion/water droplets using common power-law functions of cluster size. We show that reliable estimates of these energies can be extrapolated from a small data set comprising the results of three droplets whose sizes are between 100 and 1000 using a basic power-law function of droplet size. This agrees with an earlier conclusion drawn from a model built within the mean spherical framework and paves the road toward a theoretical protocol to systematically compute the solvation energies of complex organic ions. [ABSTRACT FROM AUTHOR]

Ammonium sulfate and sodium hypochlorite are common industrial chemicals, often used together in water treatment. The consequences of mixing hypochlorite (chlorine) solution with ammonia solutions are well understood within the chlorine industry; detonable chloramines are produced. This knowledge is not well known in other industries; fortunately, few locations have both chemicals on site. These products were inadvertently mixed, resulting in an explosion, at a water treatment facility in Kitchener, Ontario on April 2, 2014. The chemistry of the incident is presented and discussed. Facilities that handle both chemicals, such as the water treatment industry need to have heightened sense of understanding of this particular reactive chemical hazard. © 2015 American Institute of Chemical Engineers Process Saf Prog 35: 92-95, 2016 [ABSTRACT FROM AUTHOR]

Metamorphic responses of pediveliger larvae of Mytilus galloprovincialis to different ions were investigated through a series of bioassays. Effects of tetraethylammonium chloride ( TEA) on inductive effects of these above ions were also investigated. Excess ions including Li+, Cs+, Rb+ and Ca2+ induced larval metamorphosis at 10−3 M to 5 × 10−2 M in 24-h exposure assays. In continuous exposure assays, only excess Ca2+ showed inductive activity and induced 25% metamorphosis at 5 × 10−2 M. Larval responses to Li+ and Rb+were inhibited by TEA, while induction of metamorphosis by Cs+and Ca2+ was independent of the presence of TEA. Thus, these ions used can be useful inducers of larval metamorphosis for application in the aquaculture industry. The finding provides new insights on the biochemical mechanism controlling larval metamorphosis in this species. [ABSTRACT FROM AUTHOR]

A series of comb-like ionenes (C-ionenes) with aliphatic side chains were prepared via the Menschutkin reaction from amine, epichlorohydrin, and N, N, N′, N′-tetramethyl-1,6-hexanediamine. The structures of the resulting ionenes were characterized by means of charge density, H-NMR, and C-NMR. The antimicrobial properties of the ionenes were also investigated by measuring the minimum inhibition concentration (MIC) against Escherichia coli ( E. coli). The corresponding antimicrobial dynamics were studied by detecting the UV absorbance of the E. coli suspension. It was found that in comparison to the linear ionenes (L-ionenes), C-ionenes exhibited lower MIC values and faster antimicrobial effect influenced by the side chains. In particular, C-ionene with 4-carbon side chains showed MIC at 7.8 μg/mL and its aqueous solution (31.2 μg/mL) inhibited 99.9 % E. coli within 2 min. The morphologies of C-ionenes in aqueous solution were investigated by measuring their particle sizes and zeta potentials. In addition, the anti-mold tests against Aspergillus niger and Chaetomium globosum suggested that the comb-like ionenes were effective at inhibiting the growth of the fungi. [ABSTRACT FROM AUTHOR]

Abstract: In order to assess the potential chronic toxicity and tumorigenicity of ammonium perfluorooctanoate (APFO), a 2-year dietary study was conducted with male and female rats fed 30ppm or 300ppm (approximately 1.5 and 15mg/kg). In males fed 300ppm, mean body weights were lower across most of the test period and survival in these rats was greater than that seen either in the 30ppm or the control group. Non-neoplastic effects were observed in liver in rats fed 300ppm and included elevated liver weight, an increase in the incidence of diffuse hepatocellular hypertrophy, portal mononuclear cell infiltration, and mild hepatocellular vacuolation without an increase in hepatocellular necrosis. Mean serum activities of alanine aminotransferase, aspartate aminotransferase, and alkaline phosphatase were elevated up to three times the control means, primarily at the 300ppm dose. A significant increase in Leydig cell tumors of the testes was seen in the males fed 300ppm, and tumors of the liver and acinar pancreas, which are often observed in rats from chronic exposure to peroxisome proliferating agents, were not observed in this study. All other tumor types were those seen spontaneously in rats of this stock and age and were not associated with feeding of APFO. [Copyright &y& Elsevier]

Abstract: The present study investigated the neuroprotective potential of Diammonium Glycyrrhizinate (DG) in focal cerebral ischemic-reperfusion (IR) injury in mice. The middle cerebral artery occlusion (MCAO) model of the mouse was used. Mice were treated with DG (20mg/kg per day, intraperitoneal injection) or saline as control, from the beginning of the reperfusion to 7days. The focal cerebral IR injury resulted in significant neurological deficits, infarct size, and brain water content (BWC) at 1day, 3days and 7days after MCAO. A significant increase in various inflammatory mediators like interleukin-1 (IL-1), tumor necrosis factor-α (TNF-α), cyclooxygenase-2 (COX-2), inducible nitric oxide synthase (iNOS) and nuclear factor-κB (NF-κB) and astrocytic glial fibrillary acidic protein (GFAP) was also observed in the IR challenged brains. The DG treatment significantly improved neurofunction, decreased infarct size, and suppressed edema in the focal cerebral IR injury. The neuroprotective effect of DG was found to be associated with significant reduction in the IL-1, TNF-α, COX-2, iNOS, NF-κB and GFAP levels. In summary, this study suggested that DG has a neuroprotective effect on cerebral IR injury and this effect is likely related to DG''s anti-inflammatory function. [Copyright &y& Elsevier]

C13H14N2O6, monoclinic, P21/ c (no. 14), a = 3.829(1) Å, b = 20.036(5) Å, c = 8.520(2) Å, β = 93.407(3)°, V = 652.4 Å3, Z = 2, Rgt (F) = 0.0449, wRref (F2 ) = 0.1150, T = 293 K. [ABSTRACT FROM AUTHOR]

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