• KSBB Journal
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• v.11 no.5
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• pp.613-621
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• 1996

The effects of important medium components such as carbon, nitrogen sources and amino acids on the production of cyclosporin A(CyA) were investigated in an immobilized fungal cell fermentation using Tolypocladium inflatum. As carbon sources in the synthetic medium, fructose and maltose stimulated CyA production remarkably compared to glucose when ammonium sulfate was supplemented as a nitrogen source. In the absence of ammonium sulfate in the medium, however, CyA biosynthesis was reduced considerably without regard to C-sources tested. Ammonium sulfate was found to be the best N-source, and also ammonium phosphate and ammonium citrate showed some positive effects on CyA production. Optimum concentration of ammonium sulfate was 10g/L, and supplementation of ammonium sulfate at the start of fermentation was found to be the most efficacious for maximal production of CyA. Among the constituent amino acids of cyclic peptide, CyA, L-valine had the most significant effect on the biosynthesis of CyA, and maximum CyA production was observed when 10 g/L of L-valine was initially added.

• Applied Chemistry for Engineering
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• v.18 no.3
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• pp.251-254
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• 2007

Veneer plate was painted by the treatment with ammonium salts such as ammonium chloride (AMCR), ammonium sulfate (AMSF), monoammonium phosphate (MAPP), and diammonium phosphate (DAPP) at room temperature. The flame retardancy of painted veneer plate was investigated. The painted veneer plate shows an increased $CO/CO_2$ over virgin veneer and it was supposed to affect the toxicity to different extents. But when the ammonium salts were used as the retardant for veneer, the flame retardancy was improved due to the painted ammonium salts in the veneers. Also, the veneer plates with ammonium sulfate and ammonium chloride showed both the lower total smoke release (TSR) and lower total smoke production (TSP) than that of virgin veneer.

• Applied Chemistry for Engineering
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• v.18 no.2
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• pp.194-198
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• 2007

Veneer plate was painted by the treatment with ammonium salts such as ammonium chloride (AMCR), ammonium sulfate (AMSF), monoammonium phosphate (MAPP), and diammonium phosphate (DAPP) at room temperature. The physical property and flammability of painted veneer plate were investigated. In order to evaluate flammability of the treated veneer with ammonium salts, heat release rate (HRR) of the veneer was measured by a cone calorimeter according to ISO 5660-1 standard. The flammability painted veneener plate with ammonium salts was reduced compared to virgin veneer plate. The flashover possibility of veneer plates treated with these ammonium salts was examined by R. V. Petrella's classification using time to ignition and peak heat release rate. The specific gravities of veneer plates treated with only ammonium sulfate were higher than that of virgin veneer plate. Also, the veneer plates treated with ammonium salts showed lower equilibrium moisture contents over virgin veneer.

• Journal of Korea Society of Waste Management
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• v.35 no.7
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• pp.640-646
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• 2018

Biomass-fired power plants produce electricity and heat by burning biomass in a boiler. However, one of the most serious problems faced by these plants is severe corrosion. In biomass boilers, corrosion comes from burnt fuels containing alkali, chlorine, and other corrosive substances, causing boiler tube failures, leakages, and shorter lifetimes. To mitigate the problem, various approaches implying the use of additives have been proposed; for example, ammonium sulfate is added to convert the alkali chlorides (mainly KCl) into the less corrosive alkali sulfates. Among these approaches, the high temperature corrosion prevention technology based on ammonium sulfate has few power plants being applied to domestic power plants. This study presents the results obtained during the co-combustion of wood chips and waste in a circulating fluidized bed boiler. The aim was to investigate the characteristics of pollution load in domestic biomass power plants with ammonium sulfate injection. By injecting the ammonium sulfate, the KCl content decreased from 68.9 to 5 ppm and the NOx were reduced by 18.5 ppm, but $SO_2$ and HCl were increased by 93.3 and 68 ppm, respectively.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2017.05a
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• pp.978-983
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• 2017

Ammonium dinitramide(ADN) is currently under inder investigation as a replacement for ammonium perchlorate, both for environmental and toxicological reasons. Another promising application is ADN-based liquid monopropellant as a replacement for hydarzine, which is highly toxic and carcinogenic. Production of ADN is today normally performed via guanylurea dinitramide(GUDN) by reaction with potassium hydroxide to yiela potassium dinitramide(KDN). In a second reaction step, KDN is reacted with ammonium sulfate to give ADN. In our new improved process, ADN is synthesized from GUDN in one single reaction step. The simplified process improves purity, reduces the amount of by-products and allows production of ADN at a potentially lower cost, which is crucial to favour the use of ADN.

• KSBB Journal
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• v.21 no.6 s.101
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• pp.428-432
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• 2006

This study investigated the effect of sulfate source on removal efficiency in electrokinetic bioremediation which needs sulfate to degrade contaminants by an applied microorganism. The representative contaminant and the applied microorganism were phenanthrene and Sphingomonas sp. 3Y, respectively. When magnesium sulfate was used, the magnesium ion combined with hydroxyl ion electrically-generated at cathode to cause the decrease of electrolyte pH, and then the microbial activity was inhibited by that. When ammonium sulfate and disodium sulfate were used to solve the pH control problem, the pH values of electrolyte and soil solution were maintained neutrally, and also the high microbial activity was observed. With the former sulfate source, however, ammonium retarded the phenanthrene degradation, and so the removal efficiency decreased to 12.0% rather than 21.8% with magnesium sulfate. On the other hand, the latter improved the removal efficiency to 27.2%. This difference of removal efficiency would be outstanding for an elongated treatment period.

• Fisheries and Aquatic Sciences
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• v.17 no.2
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• pp.181-187
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• 2014

This study was performed to identify the optimum fractionation method and conditions to obtain exopeptidase-active fractions from octopus hepatopancreas (HP) crude extracts (CEs) using four techniques: solid ammonium sulfate fractionation, polyethylene glycol (PEG) fractionation, anion exchange chromatography, and gel filtration chromatography. The fractions with the highest total activity toward L-leucine-p-nitroanilide (Leu-pNA) were fraction IV from the ammonium sulfate and PEG fractionation, and fraction II in ion exchange and gel filtration chromatography. The total exoprotease activity of these fractions was highest in fraction IV (4,050.20 U) of ammonium sulfate fractionation, followed by fraction II (3,600.28 U) from gel filtration chromatography, fraction IV (2,861.30 U) from PEG fractionation, and fraction II (2,576.28 U) from ion exchange chromatography. These results suggest that ammonium sulfate fractionation using 60-80% ammonium sulfate was the most efficient method for separating the exoprotease active fractions from CEs of octopus HP.

• Journal of Environmental Health Sciences
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• v.22 no.3
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• pp.64-71
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• 1996

Measurement of concentration and size distribution of TSP, ammonium, nitrate and sulfate were made from Mar., 1991. to June., 1992 in Seoul. The seasonal variation of concentration and size distribution of aerosols has been investiated. Aerosol were collected and size frationated by Andersen air sampler. Size classified samples were extrated with deionized water and analyzed for ammonium, nitrate and sulfate by ion chromatography. As the results of measurement, the average of concentration and MMAD(mass median aerodynamic diameter) were $118.58 \mu g/m^3$, and $2.77 \mu m$ for TSP, $1.92 \mu g/m^3$ and $1.35 \mu m$ for ammonium, $1.34 \mu g/m^3$ and $1.58 \mu m$ for nitrate, $8.52 \mu g/m^3$ and $2.15 \mu m$ for sulfate. The Seasonal variation of concentration and size distribution was observed for ammonium, nitrate and sulfate. The concentration peak of TSP was observed in coarse particles in spring and observed in fine particles in winter. The concentration's distribution of TSP, ammonium, nitrate and sulfate was observed bimodal type during all season.

• Journal of Yeungnam Medical Science
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• v.8 no.1
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• pp.127-135
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• 1991

Successful middle ear surgery requires the availability of al safe, effective bonding material. Side effect caused by synthetic materials have led to the use of biologic adhesive. However, they carry the risk of transmission of infectious diseases if they are prepared from pooled human blood. The adhesive strength of ammonium sulfate fibrin adhesive produce an adhesive strength that is half that of the homologous commercial product. It is, however, good enough for use in several otolaryngological operations, tympanoplasty, facial nerve repair, reconstruction of ossicles, reconstruction of posterior wall of ear canal and obliteration of frontal sinus and mastoid antrum using bone dust.

• Biotechnology and Bioprocess Engineering:BBE
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• v.1 no.1
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• pp.41-45
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• 1996

Effects of yeast extract and ammonium sulfate were investigated on the production of L-or-nithine by an arginine auxotroph, Brevibacterium ketoglutamicum in flask and batch cultures. Yeast extract as an arginine source and ammonium sulfate as an inorganic nitrogen source had significant effects on L-ornithine production and cell growth. L-ornithine production was repressed by the excessive addition of arginine. Reversion of auxotrophic cells to the wild type was observed when the initial yeast extract concenfration was too low. There existed optimum concentrations of yeast extract and ammonium sulfate for L-or-nithine production. The effects of yeast extract and ammonium sulfate concentrations of the Leudeking-Piret model parameters were examined to analyze the relationship between cell growth and L-ornithine production.