• Journal of Environmental Science International
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• v.16 no.6
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• pp.677-682
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• 2007

This study was performed to provide the basic information on characteristics of groundwater pollution in Gyeongsan city. Forty two groundwater samples were collected, and pH, DO, COD, $NH_3-N,\;NO_3^--N$, T-N, $PO_4^{3-}-P$, Cl, Ca, Mg, hardness, evaporate residues and others were investigated. And, ANOVA analyses were carried out to reveal the differences in water pollution indicator values of by industry, commerce/residence and agriculture areas. The results were as follows. 1. The mean values of pH, DO, COD, $NH_3-N,\;NO_3^--N$, T-N, $PO_4^{3-}-P$, Cl, evaporate residues, Ca and hardness were 6.9, $7.9mg/\ell,\;0.4mg/\ell,\;2.44mg/\ell,\;2.73mg/\ell,\;6.06mg/\ell,\;0.82mg/\ell,\;32.72mg/\ell,\;381.67mg/\ell,\;41.53mg/\ell,\;177.17mg/\ell$, respectively. 2. As groundwater became deeper, the values of Cl, Ca, Mg, Na, hardness and evaporate residues remarkably increased, but those of COD, $NH_3^--N,\;NO_3^--N,\;NO_2^-N$, T-N decreased. 3. The values of COD, Cl, Ca, Mg, Na, hardness and evaporate residues were very high in industrial area, and those of $NH_3-N,\;NO_2^--N$, T-N were very high in commercial/residential area, and those of $NO_3^--N$ were a little high in agricultural area. 4. The correlations between depth and each value of Mg, Na, Fe, hardness and evaporate residues were highly positive, and those between DO and each value of Mg, Cu, Fe, hardness and evaporate residues were highly negative. 5. According to ANOVA analyses, the differences in three area groups (industry, commerce/residence and agriculture) on the values of $NH_3-N$, T-N, evaporate residues, hardness, Ca, Mg, K and Fe were significant at 1% level.

• Applied Chemistry for Engineering
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• v.18 no.5
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• pp.454-458
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• 2007

The removal characteristics of ionic species, such as $Ca^{2+}$, $Mg^{2+}$, $Sr^{2+}$, $SO{_4}^{2-}$, $NO{_3}^-$, and $Cl^-$ by adsorption on the alumina were investigated. Alumina precusor powders were prepared from $Al(NO_3)_3{\cdot}9H_2O$ and $NH_4OH$. Alumina materials prepared from the heat treatment in a furnace at $450{\sim}750^{\circ}C$ for 5 h were analysed using FT-IR and the Brunauer-Emmett-Teller (BET) method. The specific surface area of the product particles decreased significantly with treatment temperature. The adsorption capacities of $SO{_4}^{2-}$and $NO{_3}^-$ on alumina were 23 mg/g and 12.4 mg/g, respectively. But, removal efficiencies of $Cl^-$ were less than 4 mg/g. In general, the removal efficiencies of the anion species were decreased with increasing treatment temperature. The best anion removal efficiency was obtained when the alumina was treated under $450^{\circ}C$. Removal efficiencies of $Ca^{2+}$, $Mg^{2+}$, and $Sr^{2+}$ were increased with increasing treatment temperature.

• Analytical Science and Technology
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• v.10 no.2
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• pp.126-130
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• 1997

Electrochemical behavior of 1.0mM bis(2,2'-bipyridyl)copper( II )(${Cu(bpy)_2}^{2+}$) in 100mM NaCl+27mM $MgCl_2$ solution with and without sodium dodecyl sulfate(SDS) is investigated. In the presence of SDS, $E_{pa}$ and $E_{1/2}$ of ${Cu(bpy)_2}^{2+/1+}$ shifts to the positive direction compared to the SDS free. Teh intersection of two lines on ${\Delta}E_p$ vs. -log[SDS] plot for 1.0mM $Cu(bpy)_2(NO_3)_2$ in 100mM NaCl+27mM $MgCl_2$ solution is a critical micelle concentration(CMC). Reduced form ${Cu(bpy)_2}^{1+}$ in the presence of $MgCl_2$ is more easily associated to dodecyl sulfate anion($DS^-$) than oxidized ${Cu(bpy)_2}^{2+}$. As the ionic strength is increased by the addition of multiply charged cations($MgCl_2$), the double layer becomes more compact and micelle formation is more difficult.

• Journal of Korean Society of Environmental Engineers
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• v.33 no.7
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• pp.481-484
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• 2011

Although formation of organic chloramines have been studied for decades, most of them have involved model organic compounds (e.g., amino acids) but not naturally occurring organic nitrogen in water. This study investigated formation of organic chloramines during chlorination of 16 natural organic matters (NOM) solutions which were isolated from surface water and contained dissolved organic nitrogen (DON). Organic chloramine yields per chlorine consumption was $0.25mg-Cl_2/mg-Cl_2$. Upon chlorination of NOM solutions, organic chloramines were rapidly formed within 10 minutes. The average organic chloramine yields upon addition of chlorine in to NOM solutions were $0.78mg-Cl_2/mg-DON$ at 10 minutes and $0.16mg-Cl_2/mg-DON$ at 24 hours. Organic chloramine yields increased as the dissolved organic carbon/dissolved organic nitrogen (DOC/DON) ratios decreased. Chlorination of molecular weight (10,000 Da) fractionated samples showed that the influence of DON molecular weights on the organic chloramine formation was minimal.

• Journal of Nutrition and Health
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• v.43 no.5
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• pp.524-532
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• 2010

The Na, component of salt, can increase the risk of high blood pressure and hypertension. Especially, children are exposed to an increased risk of high sodium intake, because they often consume Na-rich processed foods and commercially prepared foods in the street. However, the database for the sodium and chloride content for these children's favorite foods is insufficient. In this study, the Na and Cl contents in 89 children's favorite foods were analyzed by using Instrumental Neutron Activation Analysis (INAA) method. The analyzed food items were presented after being classified into 33 kinds of food groups. The Na contents in 100 g children's favorite foods ranged from 0.3 mg to 35.1mg in fruits, 28.9mg to 82.5mg in milks, 127.2 mg to 602.2 mg in breads, cakes, sandwiches, and rice cakes, 2.5 mg to 1169.9 mg in candies, cookies and ice creams, 226.9 mg to 693.7 mg in commercially prepared street foods, and 103.4 mg to 875.8 mg in fast foods of westernized restaurant. Among children's favorite food groups, 100 g fried chicken, hotdog, burgers, and donuts contained an average Na of 536 mg, 553 mg, 794 mg, and 562.2 mg, respectively, so they are classified as 'high Na foods'. In contrast, 100 g fruits and dairy products contained Na an average 4.9 mg and 43.4 mg, respectively, being classified as 'low Na foods'. One serving of ramen, mandu noodle, and burger pizza can supply over 667mg Na, which is one third of the KDRI targeted intake. Likewise, the Cl contents in children's favorite foods were diverse according to food groups. The Cl contents in the analyzed foods differed from the 1.5 times of Na content, which is assumed in general. This study showed that the Na and Cl contents in children's favorite foods are very diverse. Conclusively, a strategy to reduce Na contents in the fast foods such as noodles and westernized restaurant foods is necessary for children health.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.21 no.3
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• pp.397-410
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• 2023

This study examined the efficacy of various chlorinating agents in partitioning light water reactor spent fuel, with the aim of optimizing the chlorination process. Through thermodynamic equilibrium calculations, we assessed the outcomes of employing MgCl₂, NH₄Cl, and Cl₂ as chlorinating agents. A comparison was drawn between using a single agent and a sequential approach involving all three agents (MgCl₂, NH₄Cl, and Cl₂). Following heat treatment, the utilization of MgCl₂ as the sole chlorinating agent resulted in a moderate separation. Specifically, this method yielded a solid separation with 96.9% mass retention, 31.7% radioactivity, and 44.2% decay heat, relative to the initial spent fuel. In contrast, the sequential application of the chlorinating agents following heat treatment led to a final solid separation characterized by 93.1% mass retention, 5.1% radioactivity, and 15.4% decay heat, relative to the original spent fuel. The findings underscore the potential effectiveness of a sequential chlorination strategy for partitioning spent fuel. This approach holds promise as a standalone technique or as a complementary process alongside other partitioning processes such as pyroprocessing. Overall, our findings contribute to the advancement of spent fuel management strategies.

• The Korean Journal of Food And Nutrition
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• v.6 no.2
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• pp.121-129
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• 1993

The intaking patterns of minerals of 80 high school students in urban dormitories, 16∼19 year old, In Jeonbuk province were investigated in August, 1990. Dally sodium intake of male and female students was 6,539(NaCl 16.6g), and 4,240mg(NaCl 10.8g) respectively, and their potassium intake was 2.559 and 1.696 mg respectively, Their daily calcium intake was below the RDA's, which was 549.57 mg and 359.81 mg respectively. They were offered the most source of NaCl from the soups. Male and female students were offered NaCl only 2.18 g and 1.80g respectively from Kimchi which is one of the main side dishes.

• Horticultural Science & Technology
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• v.29 no.5
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• pp.433-440
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• 2011

In head lettuce seedlings, NaCl stress was treated with hydroponic culture containing 0, 50, or with 100 mM NaCl in the seedling grown up to two leaf stages. Our focus was on the effect of NaCl on fresh and dry weights, antioxidant materials, and inorganic ion level. Fresh and dry weights of head lettuce seedlings increased with the increase in salinity while the optimal growth occured at 50 mM NaCl. The chlorophyll a (Chl a), total Chl and Chl a/b ratio increased 6 days after treatment with 100 mM NaCI. However, the Chl b content decreased. Total glutathione increased only in the root of head lettuce seedlings, whereas significant increase of total arcorbate content was observed in both shoot and root after the treatment with 100 mM NaCl. In addition, the NaCl treatment resulted in the decreased level of spermidine content, and a increased spermine content. Furthermore, $Na^+$ content in shoot and root increased significantly while $K^+$, $Ca^{2+}$, and $Mg^{2+}$ content decreased. The alteration of inorganic ion level after treatment with NaCl caused the reduction of $K^+/Na^+$, $Ca^{2+}/Na^+$, and $Mg^{2+}/Na^+$ ratio with the increase of NaCl concentration. Taken together, these findings indicate that the treatment of NaCl causes the induction of oxidative stress, and results in the alteration of metabolic mechanism in head lettuce seedlings.

• Journal of Korean Society for Atmospheric Environment
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• v.14 no.1
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• pp.11-23
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• 1998

The purpose of this study was to survey chemical distribution of inorganic elements and ions in the submicron particles, to characterize qualitatively emitting sources by factor analysis, and finally to reveal existing patterns in terms of chemical compounds by a stepwise multiple regression analysis. Total of 141 samples were collected by a cascade impactor from 1989 to1996. Fifteen chemical species (Al, Ba, Cd, K, Pb, Cu, Fe, Ni, $Cl^-, NO_3^-, SO_4^{2-}, K^+, Mg^{2+}, Ca^{2+}, and Na^+$) were characterized by AAS and IC. The study showed that average seasonal levels of submicron particulate matters $(d_p<0.43 \mum)$ were 18.7 $\mug/m^3$ in spring, 15.5 $\mug/m^3$ in summer, 15.7 $\mug/m^3$ in fall, and 24.5 $\mug/m^3$ in winter, respectively. All of the anion concentrations in the particle were highest in the winter season. By applying a factor analysis, 5 source patterns were qualitatively obtained, such as sulfate related source, nitrate related source, oil burning source, calcium related source, and coal combustion source. Finally, when applying a stepwise multiple regression analysis, the results clearly showed that $Na^+ and Ca^{2+}, K^+ and Ca^{2+}, NO_3^-$ and relative humidity, $Cl^-$ and ambient temperature, $Ca^{2+} and Cl^-, Mg^{2+} and SO_4^{2-}, Na^+ and NO_3^-, and Ca^{2+} and NO_3^-$, respectively, are negatively contributed to each other. As a result of those statistical analysis, we could suggest that some chemical compounds in the submicron particles such as$NaNO_3, MgSO_4, Ca(NO_3)_2, and CaCl_2$ may not exist on the filter as final composing products; however, other compounds may possibly exist in the form of $Mg(NO_3)_2, CaSO_4, Na_2SO_4, K_2SO_4, MgCl_2, NaCl, and KCl$. Thus, it must be necessary to identify differences between the results of above statistical analysis and of the real world by laboratory experiments.

• Korean Journal of Plant Tissue Culture
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• v.26 no.4
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• pp.259-264
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• 1999

In order to study the role of ethylene on the formation of adventitious roots, trichomes and calli, the effects of 1-aminocyclopropane-l-carboxylic acid (ACC), ethephon, $CoCl_2$ and $AgNO_3$ were investigated in the leaf segments from ecotype Columbia of Arabidopsis thaliana. When the leaf segments were cultured on the media for forming adventitious roots (0.1 mg/L NAA), trichomes (2.0 mg/L NAA) and calli (10.0 mg/L NAA), and then each cultures was treated with 1-100 mg/L of ACC and ethephon, respectively. On the adventitious root-forming medium adventitious root formation was decreased, and trichomes were induced. And on the trichome-forming medium trichome formation was decreased, and calli were induced. In order hand each culture was treated with 1-100 mg/L of $CoCl_2$ and $AgNO_3$, respectively. On the adventitious root-forming medium adventitious roots was increased without trichome formation, and on the trichome-forming medium trichome formation was decreased, and adventitious roots were induced. However on the callus-forming medium treated with ACC, ethephon, $CoCl_2$ and $AgNO_3$, respectively, callus formation was inhibited and trichomes were induced in all cultures.