• Korean Journal of Fisheries and Aquatic Sciences
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• v.16 no.3
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• pp.239-245
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• 1983

Electrochemical adsorption always was accompanied with solvent displacement and relative size factor(x) of adsorbate and solvent and hydrogen coverage(${\theta}$) on the lead anodic film electrode formed in phosphoric acid in NaCl solution and the sea water at $15{\sim}35^{\circ}C$ were studied by means of constant current-potential method and potentiodynamic cathodic polarization method. In this experiment, various constants and thermodynamic quantities calculated from the hydrogen coverage were also described to explain the reactivities of di-iso-butylnitrosoamine(DBNA) and proton ($H^+$) according to the changes of interactions between solute and solvent in the bulk phase and interphase. It was investigated that the average values of relative size factor and the coverage of hydrogen atoms studied with the electrode of lead anodic film formed in phosphoric acid solution in 60mM DBNA+0.5M NaCl and in 60mM DBNA+$6\%0$ sea water were about 11.0 and 0.2 respectively. Hydrogen evolution was electrochemical mechanism because of substitutional adsorption of aromatic substance with their delocalization of electrons, but in the case of non-charge transfer adsorption of aliphatic substance(DBNA) interacting relatively little with the electrode, it was combination mechanism.

• Proceeding of EDISON Challenge
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• 2016.03a
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• pp.120-125
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• 2016

용매화 된 이온들간의 상호작용은 화학을 비롯한 여러 분야에서 중요하게 다뤄지고 있다. 계산화학에 있어 다양한 용매에 용매화 된 이온들간의 상호작용은 분자동력학 시뮬레이션(MD)을 이용한 PMF 계산을 통해 많이 연구되어 왔는데, 본 그룹에서는 물을 표현할 수 있는 다양한 모델과 Salt solution 하에 Na+ 이온과 Cl- 이온 사이 상호작용을 PMF 계산을 통해 알아보았다. 첫 번째로 Polarizable water model인 Tip4p-fq를 사용한 PMF 계산 결과는 아직 진행 중에 있으며 결과적으로는 기본적으로 CHARMM water force field에서 제공해주는 Tip3p 모델 및 양자계산 방법 중 하나인 Ab initio를 이용한 결과와 비교, 분석 할 예정이다. 두 번째로 1M/2M/5M Salt solution의 서로 다른 농도를 사용하여 시뮬레이션 한 결과 1M과 2M에서는 물 속에서 시뮬레이션 한 결과와 큰 차이가 없었으나 농도가 짙은 5M 용매 내에선 $Na^+$이온과 $Cl^-$이온 사이 거리가 멀어질수록 주변 Salt에 영향을 받는 것을 확인 할 수 있었다. 결론적으로 본 연구를 진행함으로써 우리는 서로 다른 전하를 갖는 이온 사이 상호작용에 대한 이해를 더 높일 수 있었다.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2021.11a
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• pp.17-18
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• 2021

In the present study, Al-Zn coating was deposited by Arc thermal (AT) and plasma arc thermal (PAT) spray processes, and their corrosion characteristics were studied in 3.5% NaCl through electrochemical impedance spectroscopy (EIS), scanning electron microscope (SEM) and mechanical tests. The bond adhesion result showed that plasma arc sprayed coating had a higher value attributed to compact, dense, and less porous coating compared to arc thermal spray coating which contains defects/pores and uneven morphology as revealed by scanning electron microscope analysis. Electrochemical results revealed that the plasma arc sprayed coating had a high polarization resistance at early stage of immersion, suggesting its excellent corrosion protection performance.

• Korean Journal of Plant Resources
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• v.22 no.1
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• pp.5-12
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• 2009

Seed priming is a useful technique for rapid and uniform seed germination as well as early seedling establishment. This experiment was conducted to find out the optimum condition for Sorbus alnifolia seed priming with four concentrations of four reagents in germination property and seedling growth performance. The results are summarized as follows: Percent germination (PG) varied 2.67% to 24.67%, and S. alnifolia seeds had the highest PG in the treatment that were primed in 100mM $KNO_3$ solution for 2 days. Mean germination time was the shortest in 200 mM $KNO_3$ solution for 2 days. Seed priming with $KNO_3$ solutions increased germination speed (GS) and germination performance index (GPI) compared with non-primed seeds. Especially seed primed with 100 mM $KNO_3$ solution for 2 days showed the highest GS and GPI. The highest relative growth rate (RGR) and seedling vigor index (SVI) was significantly (p<0.05) different from the control and other treatments, respectively. RGR of height (0.0071) and root collar diameter (0.0141) of seedling from primed seeds were the highest in 400 mM NaCl solution for 2 days. The highest SVI (5.43) was observed in the seedlings from seeds primed in 100 mM $KNO_3$ solution for 2 days. Consequently, the optimum reagent and concentration were $KNO_3$ and 100 mM for the effective germination and seedling growth in S. alnifolia

• Journal of Bio-Environment Control
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• v.26 no.2
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• pp.133-139
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• 2017

This study investigated the effects of NaCl and jasmonic acid (JA) on the growth and physiological responses of spearmint (Mentha spicata L.). Spearmint was hydroponically grown for 3 weeks in modified Hoagland solution containing 0 (untreated control), JA ($20{\mu}M$ JA pretreatment), NaCl (50 mM NaCl treatment) and JA + NaCl ($20{\mu}M$ JA pretreatment + 50 mM NaCl treatment). Growth characteristics, chlorophyll, vitamin C, proline contents, DPPH scavenging activity and inorganic ion contents were evaluated. As a results, there were significant decreases in the plant height, leaf length, leaf width, and fresh weight of plants, treated with NaCl compared with control. On the other hand, the dry matters of shoot and root treated with JA + NaCl combination were better than control or NaCl treatment. Chlorophyll a and b contents in JA treatment was the highest. Vitamin C, antioxidant activity, and proline content in shoot were increased in NaCl treatment which showed low level of growth rate. The K/Na ratio, which is known to indirectly reflect the balance of ion uptake, was higher in a single treatment of JA than the control group, while lower in salt treatment (NaCl and JA + NaCl) because of high $Na^+$ absorption. In conclusion, these results showed that moderate stress treatment such as low level salt treatment and plant growth regulator jasmonic acid (JA) application would be potential strategies to improve the quality of spearmint by inducing the accumulation of secondary metabolites containing high antioxidant activity and essential oil.

• Journal of Advanced Marine Engineering and Technology
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• v.29 no.6
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• pp.692-700
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• 2005

In this study. investigated the effect of shot peening on the corrosion of SAE 5155 steel immersed in $3.5\%$ NaCl solution and corrosion characteristics by the heat treatment during shot peening process. The immersion test was Performed on the four kinds of specimens. Corrosion Potential, polarization curve, residual stress etc. were investigated from experimental results. From these test results, the effect of shot peening on the corrosion was evaluated The important results of the experimental study on the effects of shot peened SAE 5155 on the corrosion are as follows; Shot peened specimens show the low of corrosion current as compared with un peened specimens. In the case of corrosion potential, shot Peened specimen shows more negative Potential as compared with that of parent metal Surface of specimen, which is treated with shot peening Process. is Placed as more activated state against inner parent metal. Corrosion rate is shown that shot Peened specimens have less corrode than un peened specimens. But non heat treated shot peened specimens show the biggest weight loss owing to variable compressive residual stress layer by shot ball.

• Textile Coloration and Finishing
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• v.8 no.4
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• pp.42-51
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• 1996

Alkaline hydrolysis to improve the hand of PET/acetate union fabric was studied in relation to skin saponification and retarding effect of salts on the alkaline hydrolysis of cellulose acetate fiber, accelerating effect of salts on the alkaline hydrolysis of PET fiber, and changes of total hand value(T.H.V) of PET/acetate union fabric treated with alkali/salt solution. It was found that the rate of saponification of acetate was delayed by the addition of salts such as LiCl, NaCl and CH$_{3}$COONa into NaOH solution below 10 minutes. The rate of shrinkage of acetate fabric treated with 5g/l NaOH solution at 9$0^{\circ}C$ and 60 minutes showed 20 % but it was decreased 8% by. the addition of 120g/l Concentration of inorganic salts. We could know that the rate of alkaline hydrolysis of filament yarn treated with alkali solution at 9$0^{\circ}C$ and 60 minutes was delayed about 3 % using 2,000T/M of hard twist yarn, especially acetate filament treated with alkali solution at 9$0^{\circ}C$ and 10 minutes was delayed about 10%. T.H.V. of PET/acetate union fabric was increased from 2.77 to 3.04~3.18 by the addition of salts into alkali solution.

• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.2
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• pp.346-351
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• 1996

본 연구는 고등학교 1학년 여학생 25명을 대상으로 한달간 평소 염분에 대한 염미도(염분 섭취력)를 측정하여 동일한 농도의 염분용액일지라도 염분용액의 내용물에 따라 염미도에 차이를 나타내는 지의 여부를 확인하고자 1개월간 염분 섭취력을 측정하여 저염 선호 섭취력군, 정상 선호 섭취력군, 고염 선호 섭취력군으로 나누어 과거의 염분 섭취력이 짠맛 기호에 변화를 초래할 수 있는지를 조사한 것이다. 동일한 농도의 염분용액일지라도 염분용액의 내용물을 달리하는 방법으로 0.9% 동일한 농도의 순수 염분액, 1%초산과 3% 백설탕을 혼합한 혼합 염분액, 간장으로 간을 맞춘미역국, 된장으로 간을 맞춘 시금치국, 소금으로 간을 맞춘 콩나물국 등의 5종을 만들고 실험 대상자에게는 평상상태, 24시간 금식, 저단백 식사, 고단백 식사 등의 4종의 상태로 조건을 준 후 상기에서 준비된 실험용액을 맛보게 한 후 최적 염분 염미도를 짜다, 적당하다, 싱겁다로 평가하도록 하였다. 결과는 다음과 같다. (1)식염 섭취량은 고염 섭취력군에서 가장 높았으며, 한국인의 평균 섭취량 보다 높았으며, 한국인의 평균 섭취량 보다 높았다. (2)과거의 염분 섭취력이 신체조건의 변화와 용액의 종류에 따라 염분 기호에 영향을 미쳤으며 특히 간장미역국, 된장시금치국, 소금콩나물국 같은 조미된 음식을 선호하였다. (3)식염 배설량은 1일전의 섭취력과 무관하게 거의 일정하게 배설되었다.

• The Korean Journal of Physiology and Pharmacology
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• v.5 no.6
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• pp.487-494
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• 2001

During depolarization, extrusion of $Ca^{2+}$ from sarcoplasmic reticulum through forward-mode $Na^+-Ca^{2+}$ exchange was studied in the rat ventricular myocytes patch-clamped in whole-cell configuration. In order to confine the $Ca^{2+}$ responses in a micro-domain by limiting the $Ca^{2+}$ diffusion time, rat ventricular myocytes were dialyzed with high (14 mM) EGTA. $K^+$ current was suppressed by substituting KCl with 105 mM CsCl and 20 mM TEA in the pipette filling solution and by omitting KCl in the external Tyrode solution. $Cl^-$ current was suppressed by adding 0.1 mM DIDS in the external Tyrode solution. During stimulation roughly mimicking action potential, the initial outward current was converted into inward current, $47{\pm}1%$ of which was suppressed by 0.1 mM $CdCl_2.$ 10 mM caffeine increased the remaining inward current after $CdCl_2$ in a cAMP-dependent manner. This caffeine-induced inward current was blocked by $1\;{\mu}M$ ryanodine, $10\;{\mu}M$ thapsigargin, 5 mM $NiCl_2,$ or by $Na^+\;and\;Ca^{2+}$ omission, but not by $0.1\;{\mu}M$ isoproterenol. The $I{\sim}V$ relationship of the caffeine-induced current elicited inward current from -45 mV to +3 mV with the peak at -25 mV. Taken together, it is concluded that, during activation of the rat ventricular myocyte, forward-mode $Na^+-Ca^{2+}$ exchange extrudes a fraction of $Ca^{2+}$ released from sarcoplasmic reticulum mainly by voltage-sensitive release mechanism in a micro-domain in the t-tubule, which is functionally separable from global $Ca^{2+}{_i}$ by EGTA.

• Korean Chemical Engineering Research
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• v.58 no.4
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• pp.635-641
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• 2020

In this study, phase equilibria and formation behaviors of methane hydrate containing mono-ethylene glycol (MEG) and salts (sodium chloride, NaCl; sodium bromide, NaBr; sodium iodide, NaI) are investigated. Equilibrium conditions of methane hydrate containing MEG and salts are measured in a temperature range 272~283 K and a pressure range 3.5~11 MPa. Hydrate inhibition performance in the presence of additives can be summarized as follows: methane hydrate containing (5 wt% NaCl + 10 wt% MEG) > (5 wt% NaBr + 10 wt% MEG) > (5 wt% NaI + 10 wt% MEG). Formation behaviors of methane hydrate with MEG and salts are investigated for analyzing the induction time, gas consumption amount and growth rate of methane hydrates. There are no significant changes in the induction time during methane hydrate formation, but the addition of MEG and salts solution during hydrate formation can affect the gas consumption amount and growth rate.