• Journal of the Korean Society of Food Science and Nutrition
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• v.19 no.3
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• pp.201-206
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• 1990

The optimal cultural conditions for production of the bluish purple prgment by the cultivation of Streptomyces californicus KS-89 were determined with various substrates. The carbon and nitrogen sources on the production of pigment indicated that soluble strarch and glycerol as carbon sources and sodium glutamate sodium nitrate as nitrogen sources given a mzimum yield of the pigment at 3$0^{\circ}C$ for 7 days. The addition of ferrous sulfate was essential. The highest production of pigment was observed with cultivation in a medium containing 2.0% soluble starch 1% glycerol 0.5% sodium glutamate 0.05% sodim nitrate 0.001% L-proline 0.025% K2HPO4 0.005% MgSO4 .7H2O, 0.04% FeSO4.7H2O, 0.001% thiamine.HCl and pH7.0.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2003.11a
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• pp.665-670
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• 2003

This study investigated the thermodynamic and the thermal decomposition properties of high concentration nitrate salts waste water for the lagoon sludge treatment. The thermodynamic property was carried out by COACH and GEMINI II based on the composition of nitrate Salts waste water. The thermal decomposition property was carried out by TG-DTA and XRD. Ammonium nitrate and sodium nitrate were decomposed at $250^{\circ}C$$730^{\circ}C$$450^{\circ}C$$Na_2O$ into stable $Na_2O$.$Al_2O_3$. The flow sheet for nitrate salts waste water treatment was proposed based on the these properties data. These will be used by the basic data of the process simulation.

• Nuclear Engineering and Technology
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• v.9 no.4
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• pp.211-222
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• 1977

The decomposition of all the individual chemicals used in the Harwell inactive vitrification pilot plant has been studied by means of a thermal balance. Weight loss curves to 110$0^{\circ}C$ have been obtained. The four materials (sodium nitrate, cesium nitrate, lithium nitrate and ruthenium nitroso-nitrate solution) showed a greater weight loss than that based on an oxide yield, and hence these compounds of their products of decomposition are volatile below 110$0^{\circ}C$. The remaining materials suffered a weight loss no more than that corresponding to a full yield of the oxide, and hence they were not volatile below 110$0^{\circ}C$. Most of chemicals begin to decompose at less than 75$^{\circ}C$ but the nitrates of cesium, strontium, barium and sodium not until 295$^{\circ}C$ to 59$0^{\circ}C$. The results obtained can be used in the analysis of process conditions in the vitrification and calcination of highly radioactive wastes and also of the thermal decomposition behaviour of mixtures containing those materials.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2003.04a
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• pp.107-110
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• 2003

Reduction of nitrate by zero valent iron (Fe$^{0}$ ) has been previously studied, but the proper treatment for the by-product of ammonium has not been reported. However, in terms of nitrogen contamination, ammonium may be regarded as another form of nitrogen contaminants since it can be oxidized to nitrate again under aerobic conditions. This study is focused on simultaneous removal of nitrate and its by-product of ammonium, with the ZanF (Zeolite anchored Fe), a product derived from zeolite modified by Fe(II) chloride followed by reduction with sodium borohydride. Batch experiments were performed without buffer at two different pH condition with ZanF, iron filing, Fe(II)-sorbed zeolite, and pure zeolite to estimate the nitrate reduction and the ammonium production. At higher pH, removal rate of nitrate was reduced in both ZanF and iron filings. ZnF removed 60 % of nitrate at initial pH of 3.3 with no production of ammonium, while iron filing showed equivalent production of ammonium to the reduced amount of nitrate. In terms of nitrogen contamination, ZanF removed about 60 % and 40 % at initial pH of 3.3 and 6, respectively, while iron filing presented negligible removal against total nitrogen including nitrate and ammonium.

• Journal of Soil and Groundwater Environment
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• v.25 no.4
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• pp.28-34
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• 2020

Nitrate released from chemical fertilizer, animal wastes, and synthetic detergents can cause methemoglobinemia to infants, thus the standard in drinking water is set to 10 mg/L as World Health Organization recommended. In this study, zero-valent iron-modified rice straw biochar was used to reduce and remove nitrate in the aqueous phase. The rice straw biochar was prepared by pyrolyzing the biomass at 700℃ for 3 hours, and the biochar was modified using 1 M Fe(III), and the Fe(III) on the biochar was reduced to zero-valent iron using sodium borohydride. The modified biochar removed nitrate effectively, which removed more than 91% of nitrate. For the synthetic groundwater, the nitrate removal was lowered to 82% due to the presence of other anions.

• Journal of the Korean Society of Groundwater Environment
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• v.5 no.2
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• pp.66-79
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• 1998

This study purposes to elucidate the characteristics of local water quality and the evolutional process of the spring water have been studied with the samples from 55 selected springs, from the coast region to the Baegrogdam, a caldera lake of Halla mountain in Cheju Island. Results of hydrochemical analyses in the 55 spring water show that Gwaneumsa is pollued with high hydrogen concentration, and spring waters from Yusuarmchun, Jangsumul, Dukjisemmul, Sinch'onk'nmul, Youngchunsa, Woonyangchun, Harwontongmul, Dongheamul, Seakdalsengsu, Andukkyekok, Dotimul, Kinmul, Harkangmul and Jungkeummul are polluted by the pollution sources from the surface surrounding ground. Spring waters of Samyang3suwon, Meungbusa, Sernurungmul, Tosanmul, Jungkeummul, Kwakgimul, Aewolharmul, Konemul and Nokgomul are also polluted from the sea water intrusion. The electrical conductivity, pH and the concentration of nitrate nitrogen and bicarbonate increase when the precipitation increases, but the concentration of sodium, chloride and sulphate decrease when the precipitation increases. The concentrations of potassium, magnessium and calcium are nearly independent of the precipitaion. Quality characteristics of spring water show complicated group of spring water through piper's trilinear diagram. The high mountain region consists of groups of sodium or potassium type and bicarbonate type; the middle mountain region consists of groups of sodium or potassium type and no dominant type; the low mountain consists of groups of no dominant type and sulfate or nitrate type; the coast region consists of groups of sodium or potassium type and chloride type or no dominant type. These characteristics indicate that the spring waters are changed from bicarbonate type in the high and middle mountain regions into non-bicarbonate type in the coastal region, as the precipitated waters flow downslope.

• Proceedings of the KIEE Conference
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• 1990.11a
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• pp.143-149
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• 1990

A sol-gel processing of $YBa_2Cu_3O_{7-x}$ superconductor using metal nitrate salts and sodium hydroxide as the starting materials has been investigated because of the need to produce pure, hompgeneous superconducting materials. Since the precipitation of barium hydroxides can be obtained only at high basicities, the process has to be carried out Ca. pH 13 to get the simultaneous coprecipitation with the other metal hydroxides. The involved reaction mechanisms were investigated and intermediate and final products were characterized by means of thermogravimetric analysis(TGA), infra-red(IR) spectroscopy, X-ray diffraction(XRD) analysis, scanning electron microscopy(SEM), thermal mechanical analysis(TMA) and electrical measurement.

• Journal of Environmental Science International
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• v.14 no.5
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• pp.513-520
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• 2005

For the destruction of toxic chlorinated organic compounds, this study proposes improved supercritical water oxidation method (multistep oxidation) using sodium nitrate as an oxidizer. This method solves the problems involved in the existing supercritical water oxidation method. Multistep oxidation means that $NaNO_3$ is oxidized to $N_2\;via\;NaNO_2$ and NO. Toxic and hard to destroy organic substances like para-dichlorobenzen(4-DCBz), polychlorinate biphenyl(PCB) ware oxidized to non toxic substances in a condition, in which rapid pressure and temperature rise is restrained as much as possible. 4-dichlorobenzene(4-DCBz) and Polychlorinate biphenyl(PCB) in condition$(450^{\circ}C,\;p_w=0.25g/cm^3,\;30min)$ Was discomposed perfectly.

• Journal of Korean Society for Atmospheric Environment
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• v.20 no.6
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• pp.811-821
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• 2004

Low-Z particle electron probe X-ray microanalysis (low-Z particle EPMA) was applied to characterize aerosol particles collected at Gosan in Jeju island during an IOP (intensive observation period) for an international ACE-Asia project in April, 2001. Various types of atmospheric particles such as organics, carbon-rich, aluminosilicates, silicon oxide, sodium nitrate, sodium chloride, and ammonium sulfate were observed. The reacted sea salt particles such as sodium nitrate were the most abundantly encountered, but original sea salt particles were rarely observed. Since the Low-Z particle EPMA can provide quantitative information on the chemical composition of aerosol particles, many different particle types on the basis of their chemical compositions were observed and identified. In this study, it is demonstrated that the Low-Z particle EPMA can provide detailed information on the chemical compositions for the aerosol particles collected for six consecutive days in April, 2001, at Gosan super-site.

• Journal of Korean Society of Water and Wastewater
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• v.28 no.5
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• pp.555-560
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• 2014

This study investigates the effect of sodium bicarbonate ($NaHCO_3$) on growth of S.dimorphus. $NaHCO_3$ concentration was varied from 0 to 2 g-C/L. As a result, the increase in concentration of $NaHCO_3$ up to 1.5 g-C/L increased dry weight of algae. The highest specific growth rate of S. dimorphus was $0.36day^{-1}$ which was obtained at concentration of 0.5 g-C/L $NaHCO_3$. pH showed a large variation range at the concentrations lower than 0.5 g-C/L $NaHCO_3$ whereas inorganic carbon, nitrate and phosphorus removal rates were almost same at the concentrations higher than 0.5 g-C/L $NaHCO_3$ (0.75, 1, 1.25, 1.5, 2 g-C/L $NaHCO_3$). Their average inorganic carbon, nitrate and phosphorus removal rate were 70 mg-C/L/d, 11.3 mg-N/L/d, and 1.6 mg-P/L/d, respectively. Thus, $NaHCO_3$ didn't effect on inorganic carbon, nitrate and phosphorus removal rate of S. dimorphus.