• Korean Journal of Soil Science and Fertilizer
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• v.42 no.spc
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• pp.1-3
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• 2009

Silver nanoparticles have been used in agricultural practice because of their biocide effect. However, limited information is available for the effect of silver nanoparticles on soil quality. Therefore, the main purpose of this study was to evaluate effect of silver nanoparticle application on soil especially when fertilizer is applied. To simulate potassium fertilizer, potassium chloride was mixed with silver nanoparticles in soil. Concentration of silver and chloride was measured and result showed that concentration of both compounds was decreased at the range of $3.4mg\;kg^{-1}$ and 78-84% respectively after treatment. In addition, analysis of microbial population after treatment showed that microbial population was increased when silver nanoparticles and KCl were mixed. Those results indicated that application of fertilizer has impact on biocide effect of silver nanoparticles in soil.

• Journal of Oral Medicine and Pain
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• v.22 no.2
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• pp.283-294
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• 1997

타액은 분비율과 그 구성성분으로 인해 구내환경을 조절하는데 있어 가장 중요한 요인으로 여겨진다. 타액 분비율과 성분에 관한 많은 연구가 이루어 졌지만, 증령이 타액과 그 성분에 미치는 영향에 대한 연구는 상반된 결과를 보고하고 있으며 현재까지도 논란의 여지가 많다. 또한 증령에 따른 lactoferrin과 전해질의 변화는 거의 보고되지 않은 실정이다. 이에 저자는 증령이 타액분비량과 타액성분에 미치는 영향을 연구하기 위하여 59명의 투약력이 없고 건강한 사람을 대상으로 연구를 시행하였다. 연구대상을 그들의 나이에 따라 A군, 10~15세 (남자7명, 여자7명); B군,20~30세 (남자8명, 여자7명 ); C군,40~50세 (남자7명, 여자7명 ); D군,60세 이상 (남자7명, 여자9명 ) 등의 4군으로 구분하여 각각의 비자극성 전타액을 표준화된 방법으로 채취한후 타액분비량과 immunoglobulin, lactoferin 및 전해질의 변화를 측정하였다. 이와 같은 실험을 통해 다음과 같은 결론을 얻었다. 1. 비자극성 타액분비량은 각 연령군간의 유의한 차이가 관찰되지 않았으며, 20-30세 군(B군)에서만 남성에 비해 여성에서 유의하게 낮았다. 2. 인체 전타액내 IgA와 lactoferin 농도는 연령이나 성별에 따른 뚜렷한 변화는 없었지만, 10-l5세 군(A군) 남성에서 유의하게 낮았다. 3. 인체 전타액내 IgG의 농도는 연령이나 성별에 따른 차이가 관찰되지 않았다. 4. 인체 전타액내 IgM의 농도는 60세이상 군(D군) 남성에서 유의하게 낮은 농도를 보였다. 5. 인체 전타액내 전해질(sodium, chloride, potassium, magnesium)의 농도는 증령에 따라 증가하는 경향을 보였다. magnesium과 chloride는 60세이상 군(D군)에서, sodium과 potassium은 40-50세 군(C관)에서 최대치를 보였다 성별간의 유의성 있는 차이는 발견되지 않았다.

• Korean Journal of Food Science and Technology
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• v.29 no.5
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• pp.1071-1074
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• 1997

The Effect of $Ca^{++}$, $K^+$ and $Mg^{++}$ on salting of radish was investigated. Up to 0.2 M of $Ca^{++}$ and/or $K^+$, sodium chloride content of radish increased respectively, comparing with no addition of these ions. The salting effect of radish incereased in proportion to the concentration ($0{\sim}0.01\;M$) of $Ca^{++}$ and/or $K^+$ in the salting solution up to 0.2 M, while there was no influence of $Mg^{++}$. When $Mg^{++}$ and $Ca^{++}/Mg^{++}$ and $K^+$ were added to brine solution, $Ca^{++}$ or $K^+$ influenced the salting effect of radish and $Mg^{++}$ did not.

• Korean Journal of Food Science and Technology
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• v.14 no.4
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• pp.315-323
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• 1982

The measurement of cell constant in a diaphragm-cell method is the most important factor. In order to get the correct cell constant, the diffusion coefficients of potassium chloride were measured, at various concentration and temperature of potassium chloride solution, and at the stirring rate in the cell. The pseudo-binary diffusion coefficients of organic aroma component (benzaldehyde) in sugar solution has been measured at various concentration and temperature with the cell constant obtained above. Experimental results were compared and discussed with the semi-empirical epuations from literatures. And, especially, the diffusion coefficient of benzaldehyde, $D_{ba}$ for a small solute diffusing in a viscous solvent of larger molecules is proportional to the -0.82 power of the viscosity of aqueous sugar solution, ${\mu}$ at constant temperature, $D_{ba}{\mu}^{0.82}=constant$.

• Korean Journal of Microbiology
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• v.8 no.1
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• pp.41-51
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• 1970

In previous paper, it was reported that antibiotic substance such as tetracycline and streptomycin were produced by S'. albus subsp. and S'. globosus. And increase of mycelial growth of two strains, antibiotic production, and changes of pH range are extended to approximately 110-130 hrs in fermenting medium, there-after they decreased with culture period exception of pH range. Two Streptomyces spp. required commonly 4-5% starch as carbon sources and 1.5-2.0% soybean meal as nitrogen sources. However, 0.005-0.01M potassium phosphate dibasic, calcium carbonate (6mg/ml in S.albus subsp. and 2mg/ml in S. globosus), 0.01-0.03M, magnesium sulgate and 0.01M ferric chloride showed as optimal concentration for the growth of 2 strains. Mineral compoments such as zinc, manganese, cobalt, sodium and copper at the level of 10$^{-4}$ -10$^{-6}$ M were observed. Especially, zinc ion showed toxicity to the growth of 2 strains at 0.005M. In relation with pH, there is a little difference in mycelial growth with cultural initial pH.

• CELLMED
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• v.9 no.1
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• pp.2.1-2.6
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• 2019

Decoction of Cocos nucifera husk fibre is used indigenously in Nigeria for malaria treatment. Polyphenols have been identified as the phytochemicals responsible for the antimalarial activity of Cocos nucifera husk fibre, though their toxicity has not been evaluated. The polyphenols of Cocos nucifera husk fibre were therefore evaluated for their effects on selected kidney function indices in mice. Fifty mice were randomly divided into five groups (A-E) of ten mice each. Mice in group A were orally administered 5% DMSO solution while those in groups B, C, D and E were orally administered 31.25, 62.5, 125 and 250 mg/Kg body weight of the polyphenols respectively for seven days. Serum urea, creatinine and uric acid concentrations were determined. Serum levels of sodium, potassium, chloride and calcium ions and kidney alkaline phosphatase (ALP), glutamate dehydrogenase (GDH) and gamma-glutamyltransferase (GGT) activities were also determined. The results showed that the polyphenols significantly reduced (p<0.05) urea concentration at 250 mg/Kg body weight and creatinine concentration at all doses compared to controls. The polyphenols caused no significant alteration (p>0.05) in serum uric acid concentration and kidney ALP, GGT and GDH activities compared to controls. There was significant increase (p<0.05) in serum sodium ion concentration at 31.25, 125 and 250 mg/Kg body weight of polyphenols whereas significant increase (p<0.05) in serum potassium and chloride ions was observed at 62.5 and 250 mg/Kg body weight compared to controls. Thus, polyphenols of Cocos nucifera husk fibre may adversely affect some osmoregulatory functions of the kidney, especially at higher concentrations.

• Restorative Dentistry and Endodontics
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• v.44 no.1
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• pp.4.1-4.10
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• 2019

Objectives: Biofilm formation is critical to dental caries initiation and development. The aim of this study was to investigate the effects of nicotine exposure on Streptococcus mutans (S. mutans) biofilm formation concomitantly with the inhibitory effects of sodium chloride (NaCl), potassium chloride (KCl) and potassium iodide (KI) salts. This study examined bacterial growth with varying concentrations of NaCl, KCl, and KI salts and nicotine levels consistent with primary levels of nicotine exposure. Materials and Methods: A preliminary screening experiment was performed to investigate the appropriate concentrations of NaCl, KCl, and KI to use with nicotine. With the data, a S. mutans biofilm growth assay was conducted using nicotine (0-32 mg/mL) in Tryptic Soy broth supplemented with 1% sucrose with and without 0.45 M of NaCl, 0.23 M of KCl, and 0.113 M of KI. The biofilm was stained with crystal violet dye and the absorbance measured to determine biofilm formation. Results: The presence of 0.45 M of NaCl, 0.23 M of KCl, and 0.113 M of KI significantly inhibited (p < 0.05) nicotine-induced S. mutans biofilm formation by 52%, 79.7%, and 64.1%, respectively. Conclusions: The results provide additional evidence regarding the biofilm-enhancing effects of nicotine and demonstrate the inhibitory influence of these salts in reducing the nicotine-induced biofilm formation. A short-term exposure to these salts may inhibit S. mutans biofilm formation.

• Korean Journal of Veterinary Research
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• v.34 no.1
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• pp.25-36
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• 1994

The inward tail current after a short depolarizing pulse has been known as Na-Ca exchange current activated by intracellular calcium which forms late plateau of the action potential in rabbit atrial myocytes. Chloride conductance which is also dependent upon calcium concentration has been reported as a possible tail current in many other excitable tissues. Thus, in order to investigate the exsitance of the calcium activated chloride current and its contribution to tail current, whole cell voltage clamp measurement has been made in single atrial cells of the rabbit. The current was recorded during repolarization following a brief 2 ms depolarizing pulse to +40mV from a holding potential of -70mV. When voltage-sensitive transient outward current was blocked by 2 mM 4-aminopyridine or replacement potassium with cesium, the tail current were abolished by ryanodine$(1{\mu}M)$ or diltiazem$(10{\mu}M)$ and turned out to be calcium dependent. The magnitudes of the tail currents were increased when intracellular chloride concentration was increased to 131 mM from 21 mM. The current was decreased by extracellular sodium reduction when intracellular chloride concentration was low(21 mM), but it was little affected by extracellular sodium reduction when intracellual chloride concentration was high(131 mM). The current-voltage relationship of the difference current before and after extracellular sodium reduction, shows an exponential voltage dependence with the largest magnitude of the current occurring at negative potentials, with is similar to current-voltage relationship at negative potentials, which is similar to current-voltage relationship of Na-Ca exchange current. The current was also decreased by $10{\mu}M$ niflumic acid and 1 mM bumetanide, which is well known anion channel blockers. The reversal potentials shifted according to changes in chloride concentration. The current-voltage relationships of the niflumic acid-sensitive currents in high and low concentration of chloride were well fitted to those predicted as chloride current. From the above results, it is concluded that calcium activated chloride component exists in the tail current with Na-Ca exchange current and it shows the reversal of tail current. Therefore it is thought that in the physiologic condition it leads to rapid end of action potential which inhibits calcium influx and it contributes to maintain the low intracellular calcium concentration with Na-Ca exchange mechanism.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2017.10a
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• pp.74-74
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• 2017

Electrorefining is a key step in pyroprocessing. The electrorefining process is generally composed of two recovery steps - the deposit of uranium onto a solid cathode and the recovery of the remaining uranium and TRU elements simultaneously by a liquid cadmium cathode. Uranium deposit recovered from the solid cathode is a dendritic powder. It is necessary to separate the adhered salt from the deposits prior to the consolidation of uranium deposit. The adhered salt is composed of lithium, potassium, uranium, and rare earth chlorides. Distillation process was employed for the cathode processing. One of the operation methods is distillation of the salt at low temperature ($900^{\circ}C$), and then melting of the deposit at high temperature to avoid a backward reaction. For the development of the salt distiller, the distillation behavior of the low vapor pressure chlorides should be studied. Rare earth chlorides in the adhered salt of uranium deposits have relatively low vapor pressures compared to the process salt (LiCl-KCl). In this study, the evaporation rates of the lanthanum and neodymium chlorides were measured for the salt separation from electrorefiner uranium deposits in the temperature range of $825{\sim}910^{\circ}C$. The evaporation rate of both chlorides increased with an increasing templerature. The evaporation rate of lanthanum chloride varied from 0.12 to $1.68g/cm^2/h$. Neodymium chloride was more volatile than lanthanum chloride. The evaporation rate of neodymium chloride varied from 0.20 to $4.55g/cm^2/h$. The evaporation rate of both chlorides are more than $1g/cm^2/h$ at $900^{\circ}C$. Even though the evaporation rates of both chlorides were less than that of the process salt, the contents of the lanthanide chlorides were small in the adhered salt. Therefore it can be concluded that $900^{\circ}C$ is suitable for the operation temperature of the salt distiller.

• Journal of the Korea Institute of Building Construction
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• v.23 no.4
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• pp.349-358
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• 2023

This research aimed to enhance the initial strength of concrete that is mixed with ground granulated blast furnace slag, as well as to fortify its resistance to carbonation and chloride ion permeation. To achieve this, alkaline aqueous, produced through the electrolysis of potassium carbonate, was employed as the mixing water in the preparation of concrete. To substantiate the increment in initial strength, compressive strength measurements of the concrete were executed. Additionally, an accelerated carbonation test and a chloride ion permeation resistance test were undertaken. The results confirmed that the initial strength of the concrete, which utilized electrolysis alkaline aqueous as mixing water, exhibited an improvement in comparison to concrete mixed with conventional water. It was also verified that both carbonation resistance and chloride ion permeation resistance showed enhancements.