• Journal of the Korean Chemical Society
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• v.31 no.6
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• pp.534-541
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• 1987

The study of reaction mechanism for the substitution of ethylenediamine (en) for Cl and Hedta from $[CoCl(Hedta)]^-$ in the presence of $Hg^{2+}$ ion was carried out by uv and CD spectra. From the kinetic data, we proposed that the first ethylenediamine be substituted through the associative reaction path by means of interaction of $Hg^{2+}$ ion with Co(III), and that the second and the third ethylenediamine be substituted stepwise. From the optical purities of $[Co(en)_3]^{3+}$ which was formed after reaction, we suggested the critical stereochemical step and new substitution reaction paths.

• Toxicological Research
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• v.14 no.4
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• pp.577-585
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• 1998

Cadmium is an important industrial and environmental pollutant and has adverse effects on cell growth and metabolism, although the mechanisms of its cellular toxicity are still unclear. This study was performed to elucidate the cytotoxic mechanism of cadmium in the viewpoint of oxidative stress and cytoskeleton alterations in WB-F344 rat liver epithelial cells. 200 $\mu\textrm{M}$ $CdCl_2$ caused a severe disassembling of microtubule and micro filament and an apparent cell retraction under an observation with fluorescence micoscope. (equation omitted)-tubulin and F-actin protein were highly thiolated at 20 min and then disappeared from 1 hour after the treatment of 200 $\mu$M CdCl$_2$in the immunoblot analysis. Intracellular GSH was decreased from 1hr to 24 hrs by 66.6 or 200 $\mu\textrm{M}$ of $CdCl_2$. Intracellular protein thiol was also decreased by 22.2, 66.6 and 200 $\mu\textrm{M}$ of $CdCl_2$ at 1 hour after its treatment. The product of lipid peroxidation (malondialdehyde) was increased from 4 hrs by 66.6 and 200$\mu\textrm{M}$ of $CdCl_2$. These data indicate that cadmium induces oxidative stress involving disassembling of microtubule and micro filament, thiolation of (equation omitted)-tubulin and actin protein, depletion of GSH and protein thiol, and increase of lipid peroxidation.

• Korean Journal of Metals and Materials
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• v.47 no.5
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• pp.297-303
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• 2009

Solvent extraction experiments of cupric and cuprous chloride with Alamine336 have been performed from HCl solution. In order to identify the solvent extraction reaction, distribution diagram of cupric and cuprous species with HCl concentration was obtained by considering complex formation reaction and the activity coefficient of solutes with Pitzer equation. Analysis of the solvent extraction data by graphical method together with the distribution diagram of copper indicated that solvent extraction reaction of copper with Alamine336 depends on HCl concentration. In strong HCl solution of 3 and 5 M, ${CuCl_4}^{2-}$ and ${CuCl_3}^{2-}$ took part in the solvent extraction reaction as Cu(II) and Cu(I), respectively. When HCl concentration was 1 M, ${CuCl_2}^-$ was extracted into the organic phase in the case of Cu(I) while adduct formation between $Cu^{2+}$ and Alamine336 was responsible for the solvent extraction reaction of Cu(II).

• Asian-Australasian Journal of Animal Sciences
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• v.29 no.7
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• pp.1013-1021
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• 2016

This study developed probabilistic models to predict Salmonella growth in processed meat products formulated with varying concentrations of NaCl and $NaNO_2$. A five-strain mixture of Salmonella was inoculated in nutrient broth supplemented with NaCl (0%, 0.25%, 0.5%, 0.75%, 0.5%, 1.0%, 1.25%, and 1.75%) and $NaNO_2$ (0, 15, 30, 45, 60, 75, 90, 105, and 120 ppm). The inoculated samples were then incubated under aerobic and anaerobic conditions at $4^{\circ}C$, $7^{\circ}C$, $10^{\circ}C$, $12^{\circ}C$, and $15^{\circ}C$ for up to 60 days. Growth (assigned the value of 1) or no growth (assigned the value of 0) for each combination was evaluated by turbidity. These growth response data were analyzed with a logistic regression to evaluate the effect of NaCl and $NaNO_2$ on Salmonella growth. The results from the developed model were compared to the observed data obtained from the frankfurters to evaluate the performance of the model. Results from the developed model showed that a single application of $NaNO_2$ at low concentrations did not inhibit Salmonella growth, whereas NaCl significantly (p<0.05) inhibited Salmonella growth at $10^{\circ}C$, $12^{\circ}C$, and $15^{\circ}C$, regardless of the presence of oxygen. At $4^{\circ}C$ and $7^{\circ}C$, Salmonella growth was not observed in either aerobic or anaerobic conditions. When $NaNO_2$ was combined with NaCl, the probability of Salmonella growth decreased. The validation value confirmed that the performance of the developed model was appropriate. This study indicates that the developed probabilistic models should be useful for describing the combinational effect of $NaNO_2$ and NaCl on inhibiting Salmonella growth in processed meat products.

• Journal of Soil and Groundwater Environment
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• v.29 no.4
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• pp.44-57
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• 2024

Calcium chloride (CaCl₂) and industrial sodium chloride (NaCl) are commonly used as deicing agents in Korea, which are expected to release dissolved chloride ions into the road surfaces following their application. This study aimed to comprehensively assess the usage of deicing agents and variations in groundwater quality between 2016 and 2022 by analyzing public data provided by various domestic institutions. Additionally, the study sought to identify factors contributing to deteriorating road conditions by comparing the amount of CaCl₂ appied and the incidence of potholes. Pothole occurrences during the study period were primarily reported during heavy rainfall periods without application of deicing agents. In 2022, chloride ion concentrations in groundwater in the southeastern Korean Peninsula were significantly higher than in previous years, coinciding with severe cold waves and heavy snowfall that resulted in increased deicing agent use. However, further data collection and verification are needed to distinguish between the effects of seawater intrusion and deicing agents. Despite limitations in the completeness and consistency of public data, the research highlighted the urgent need for improved data quality and further field verification to fully understand and mitigate the environmental impacts of deicing agents.

• Korean Journal of Food Science and Technology
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• v.38 no.5
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• pp.720-723
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• 2006

The viability of Shigella sonnei, a significant cause of gastroenteritis in Korea, on TSA plates was determined after sublethal heating treatments and NaCl treatments. In addition, recovery levels of sublethally injured cells on TSA plates containing different concentrations of NaCl (TSAS) were investigated. The viability decreased significantly with increasing degree of sublethal heating treatments, but increases in NaCI treatment concentration from 0 to 6% had little effect on the viability. After being sublethally treated at $55^{\circ}C$ for 30 min, bacterial populations were reduced by 7.58, 7.83 and 7.93 log CFU/mL on 2, 4, and 6% TSAS, respectively. After being sublethally treated at $60^{\circ}C$ for 30 min, bacterial populations were reduced by 6.71, 6.73, and 6.73 log CFU/mL on 2, 4 and 6% TSAS, respectively. Decimal reduction times (D-values) decreased with increasing NaCl treatment concentrations after sublethal heating at 55 or $60^{\circ}C$. These data imply that the S. sonnei cells sublethally injured by insufficient heating processes had a lower recovery rate with increasing NaCl concentrations in the recovery media.

• Journal of the Korean Electrochemical Society
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• v.4 no.3
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• pp.87-93
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• 2001

Pressure-balanced external Ag/AgCl electrode has been extensively used for both Pressurized Water Reactor (PWR) and Boiling Water Reactor (PWR) environments. The use of KCI-based buffer solution often becomes the source of electrode potential drift due to slow leakage through its porous plug, typically made of zirconia. It is reported that results of our effort to improve the stability of electrode potential by using high purity water as the filling solution in which $Cl^-$ ion activity can be established and maintained at the solubility of AgCl even with the sustained leakage for a long period. Stability tests have been made in boron and lithium mixture solution at $288^{\circ}C$. The electrode potential remained stable within 10 mV over one week period. And after a thermal cycle between 288 to $240^{\circ}C$ the potential shift of Ag/AgCl electrodes did not exceed 15 mV By using the limiting equivalent ionic conductances and Agar's hydrodynamic theory, the thermal liquid junction potential (TLJP) of the electrode has been predicted. The calculated values for the water-fiued Ag/AgCl electrode potential, in which the chlorine concentration in the filling solution was derived from the measured data at ambient temperature, had a good agreement with the experimental values.

• The korean journal of orthodontics
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• v.54 no.6
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• pp.411-421
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• 2024

Objective: To investigate which types of environmental exposure during pregnancy are risk and protective factors for cleft lip with or without cleft palate (CL/P). Methods: This case-control study included 278 orthodontic patients with CL/P (CL/P group) and 51 without CL/P (non-CL/P group). Demographic and environmental exposure data were collected using questionnaires completed by the parents. Statistical analyses were performed to identify the potential risk and protective factors for CL/P. Results: The two groups did not show significant difference in (1) body weight at birth and number of previous births; (2) fathers' ages at birth and occupation; (3) parents' chronic diseases, alcohol consumption, and exposure to harmful substances; and (4) mothers' smoking, secondhand smoking, and vitamin and calcium intake. Most patients with CL/P were born at normal term (≥ 37 weeks, 93.2%) with normal body weight (2.9-3.7 kg, 63.7%) and as either the first or second child (90.3%). In the CL/P group, the percentages of mothers who were very young or old (≤ 19 years, ≥ 40 years) and with physical labor in their occupation were low (1.8% and 2.2%, respectively). Compared with the non-CL/P group, the CL/P group showed a lower percentage of maternal folic acid intake (68.6% vs. 20.9%, odds ratio [OR] = 0.121; P < 0.001) and higher percentages of mothers' drug intake and fathers' smoking habits (3.9% vs. 16.2%, OR = 4.73, P < 0.05; 39.2% vs. 61.2%, OR = 2.44, P < 0.01). Conclusions: The findings of this study may explain the association between environmental factors and CL/P risk.

• The Korean Journal of Ecology
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• v.27 no.1
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• pp.43-47
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• 2004

This research was investigated to prepare basic data in a study on the copper tolerance of herbaceous plants through the growth rate and the elimination rate dependent on Cu concentration of 6 species; Commelina communis, Medicago sativa, Echinochloa frumentancea, Zea mays, Helianthus annuus and Abutilon avicennae, We examined the germination rate, root and shoot growth of seedling and fresh biomass of 6 species (Commelina communis, Medicago sativa, Echinochloa frumentancea, Zea mays, Helianthus annuus and Abutilon avicennae) painted to Cu contaminated soil (50, 100, 200, 300-CuCl₂/㎏) and control for 14 days. The germination rate of H. annuus, E. frumentancea and C. communis were not affected by Cu concentration. However, root and shoot growth of H. annuus was about 7% of control and the biomass was 35% of control at 300 ㎎-CuCl₂/㎏. E. frumentancea and C. communis that showed good growth rate at higher Cu contaminated soil (>200 -CuCl₂/㎏), were the most tolerant plant to Cu concentration. Especially, E. frumentancea eliminated over 30% of Cu in soil and the amount of Cu uptake increased with increasing Cu concentration; 1,020㎎ Cu per 1 ㎏ of soil at 300 ㎎-CuCl₂/㎏. From these results, we concluded that E. frumentancea would be used for phytoremediation.

• Journal of Korean Biological Nursing Science
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• v.3 no.2
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• pp.51-61
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• 2001

This study was done to investigate the effect of the first experience of the clinical experience for psychiatric nursing on urinary $Na^+$, $Cl^-$, $K^+$, $Ca^{++}$ of the nursing students. We analyzed the urine of 36 students on curriculum who were students of D college in K city. The data were analyzed with SAS Statistical analysis was performed by using paired t-test, GLM. The second day group increased 18.56 at 8AM, 31.90 at 4PM in case of $Na^+$(p=0.004). The second day group increased 27.61 at 8AM, 45.53 at 4PM in a case of $Cl^-$(p=0.009). The first day group increased 2.62 at 8AM, 7.09 at 4PM in case of $K^+$(p=0.018). The second day group increased 3.69 at 8AM, 5.19 at 4PM in a case of $K^+$(p=0.013). The second day group increased 20.65 at 8AM, 14.07 at 4PM in a case of $Ca^{++}$(p=0.033). There was a significant difference in $Na^+$ according to group at 8AM(F=4.17, p=0.024) and 4PM(F=3.58, p=0.040). There was a significant difference in $Cl^-$ according to group at 8AM(F=4.38, p=0.020) and 4PM(F=6.29, p=0.003). There was a significant difference in $K^+$ according to group at 8AM(F=5.03, p=0.012). In conclusion, $Na^+$, $Cl^-$, $K^+$, $Ca^{++}$ may be used as a indicator of the amount of stress to improve the educational environment for the students.