• 전기화학회지
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• 제11권3호
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• pp.159-164
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• 2008

변전위법, 순환전압전류법, 대시간전류법 및 대시간전기량법을 이용하여 구리의 산화 용해반응에 미치는 $Cl^-$의 영향을 조사하였다. 아르곤 분위기의 NaCl 수용액에서 Cu의 산화 용해반응은 전반응식 $Cu+2Cl^{-}{\rightleftharpoons}{CuCl_2}^{-}+e^-$ 에 따라 일어나며, Cu 표면에 $Cl^-$가 흡착하는 과정에 잘 맞는 등온식은 Temkin 흡착등온식 임을 알 수 있었다.

• Geomechanics and Engineering
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• 제25권3호
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• pp.245-251
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• 2021

The present study investigated the ageing effect on compressibility, permeability and shear strength behavior of kaolin and bentonite samples in the presence of NaCl and CaCl₂ solutions. The compressibility, permeability and shear strength parameters were determined on the 60, 190, and 250 days cured samples. The results have shown that, the kaolin sample becomes more compressible in the presence Ca²⁺ ions with ageing. Generally, the normalized compression index values of bentonite samples increased at the end of 60 days and 250 days curing time periods. The normalized permeability value of kaolin decreased by ageing in the presence of Na⁺ ions almost twofold. The permeability values of bentonite increased both in NaCl and CaCl₂ solutions during ageing. In the presence of Na⁺ ions kaolin had higher max. shear stress value than Ca²⁺ ions. When the max. shear stress values of 0, 60 and 190 days samples were compared, it was seen that NaCl solution had no significant effect on the shear strength of kaolin sample. However, the shear strength of kaolin increased in the CaCl₂ solution during ageing. In the presence of Ca²⁺ ions the max. shear stress value of bentonite was higher. The results of this study have shown that ageing has significant effects on the compressibility, permeability and shear strength of kaolinitic and bentonitic clayey soils.

• 한국식품영양학회지
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• 제9권3호
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• pp.325-330
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• 1996

Foaming capacity (FC) and stability (FS) of protein recovered from red crab (Chitinonecetes opilio) processing in water and soybean protein isolate were determined at pH 2.0~10.0 in water and NaCl solution. The FC values for both proteins showed the lowest values at the isoelectric point (pH 4.0) and increased nth an increase in pH above the isoelectric point. FC of RCP was higher than that of SPI at pH 10.0 in water and both NaCl solutions. FC of SPI increased with an increase in NaCl concentration at pH 4.0 and 6.0, but FC of RCP was not affected. The highest FS values for both proteins were obtained at pH 4.0 in water. At pH 2.0, FC of RCP decreased with NaCl concentration increase, but FS increased. NaCl concentration had little effect on FS of RCP at pH 4.0 and 6.0, but the FS decreased at pH 10.0. FS of SPI was similar to that of RCP at pH 2.0 and increased with NaCl concentration Increase from 0.1 to 0.5M NaCl at pH 10.0.

• 한국식품영양학회지
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• 제25권2호
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• pp.393-397
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• 2012

본 연구에서는 온도 변화 방법을 이용하여 조미계란을 신속하게 제조하기 위한 가염방법을 개발하고자 하였다. 먼저 염지액의 농도에 따른 계란 내부로 염분의 침투 효과를 분석한 결과, 20, 30 및 40%의 염지액에서 2시간 동안 염지시킨 각각의 계란내 염분 함량은 0.51, 0.57 및 0.60%를 나타내어 농도가 높아질수록 침투효과가 향상되는 것을 확인할 수 있었으며, 고온에서 저온으로 계란의 온도 변화를 유도한 온도변화 방법을 적용한 경우 2시간 동안 계란내 염분 함량이 각각 0.49, 0.56 및 0.70%를 나타내어 40%의 염지액에서 염분의 침투 효과가 향상되었다. 그리고 4, 5 및 7 MPa의 압력을 가하여 40%의 염지액으로 15분간 염지한 경우, 각각 1.14, 1.36 및 1.45%의 염분 함량을 나타내어 대기압 조건에서 침투시킨 결과보다 빠르게 침투되었다. 온도 변화 방법을 적용하여 4, 5 및 7 MPa의 압력을 가하여 40%의 염지액으로 15분간 염지한 경우 각각 1.52, 1.62 및 1.66%의 염분 함량을 나타내어 온도 변화 방법에 의해 침투 효과가 향상됨을 확인할 수 있었다. 이는 계란의 온도 변화 방법이 계란 내부 난막의 수축효과로 외부 염분의 흡입을 유도하였기 때문으로 생각되며, 조미계란을 신속하게 제조하기 위한 가염 방법으로 온도 변화 방법의 적용이 매우 효과적이라고 생각된다.

• Corrosion Science and Technology
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• 제8권5호
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• pp.193-196
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• 2009

For the estimation of uncertainty in potentiodynamic polarization resistance measurement, the type A uncertainty was measured using type 316 stainless steel in an acidified NaCl solution. Sensitivity coefficients were determined for measurand such as scan rate of potential, temperature of solution, concentration of NaCl, concentration of HCl, surface roughness of specimen and flow rate of purging gas. Sensitivity coefficients were large for the measurand such as the scan rate of potential, temperature of solution and roughness of specimen. However, the sensitivity coefficients were not the major factors influencing the combined standard uncertainty of polarization resistance due to the low values of uncertainty in measurements of the measurands. A major influencing factor was the concentration of NaCl. The value of type A uncertainty was 1.1 times the value of type B uncertainty, and the combined standard uncertainty was 10.5 % of the average value of polarization resistance.

• 한국작물학회지
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• 제59권2호
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• pp.139-143
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• 2014

본 연구는 한국 서남해안지역에 분포하고 있는 갯개미자리의 염농도에 따른 발아와 생장반응을 구명하고자 수행하였으며 결과는 아래와 같다. 1. 갯개미자리의 염농도 및 온도별 발아율을 조사한 결과, NaCl 0~1.0%에서는 $15^{\circ}C$에서 발아율이 90% 이상으로 높았고, NaCl 2.0%에서는 모든 온도에서 발아가 되지 않았다. NaCl 0%에서 발아율은 $10^{\circ}C$에서 $20^{\circ}C$까지는 90% 이상을 보였지만, $25^{\circ}C$에서는 51.7%로 급격히 낮아졌다. 또한 $15^{\circ}C$에서 NaCl 농도별 발아율이 80% 이상 되는 시기는 NaCl 0%와 0.3%에서는 5일, NaCl 0.5%에서는 7일, NaCl 1%에서는 9일이었고, NaCl 2%에서는 발아하지 못하였다. 2. 염농도별로 8주 동안 양액재배한 결과, 염농도가 NaCl 0, 50, 100, 200, 300, 400 mM에서는 NaCl 50 mM 처리구가 초장 12.5 cm, 건물중 0.73 g로 생장이 가장 좋았다. 또한 해수 0, 12.5, 25, 50, 100%에서는 해수 12.5% 처리구가 초장 20.9 cm, 건물중 0.72 g으로 생장이 가장 좋았으며, 이들 염농도는 모두 NaCl 0.3% 수준이었다. 3. 염농도에 따른 무기성분 함량은 NaCl 농도가 높을수록 $Na^+$ 함량은 높아졌지만, $K^+$과 $Ca^+$, $Mg^+$은 낮아지는 경향을 보였다. 특히 $Na^+$ 함량과 $K^+$ 함량이 대조적으로 변화하였으며, 이들은 NaCl 50 mM에서 함량이 급격히 변화한 다음 NaCl 400 mM까지 완만한 함량 변화를 보였다. 4. 이상의 결과로 볼 때, 갯개미자리는 안정적인 발아를 위해 NaCl 1.0% 이하에서 $15^{\circ}C$ 유지가 필요하고 재배에서는 NaCl 0.3% 수준이 적정 염농도로 생각 된다.

• Corrosion Science and Technology
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• 제20권2호
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• pp.77-84
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• 2021

This study aims to optimize the DL-EPR test solution for duplex stainless steel S31083 using the Taguchi design. The test solution parameters applied to the Taguchi design are H₂SO₄, NaCl, KSCN concentration, and temperature. In the experimental design, an orthogonal array of 4 levels 4 factor L₁₆(4⁴) was used. Output values for the orthogonal array were used for resolution (degree of sensitization) and selective etch (I_a) values. The optimal test solution conditions were selected by comparing the normalized S/N ratio for the two reaction properties. As a result, the H₂SO₄ and NaCl were identified as the main factors influencing the sensitivity measurement, but the delta statistics showed that the KSCN concentration and temperature had relatively low influence. The optimal condition was identified as 1.5 M H₂SO₄+0.03 M KSCN+1.5M NaCl at 30 ℃. The degree of sensitization presented a tendency to depend on the heat treatment temperature and time in the optimal test solution. This investigation confirmed the possibility of optimizing the experiment solution for the DL-EPR test of stainless steel using the Taguchi technique.

• 한국작물학회지
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• 제42권2호
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• pp.134-140
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• 1997

수도의 내염성 품종 안나프르나에 NaCl 50 mM을 처리하여 유도된 단백질의 분리정제를 수행하여 한 개의 새로운 단백질을 분리 정제하였다. 그 결과는 다음과 같다 1. 10일된 유묘에 50mM NaCl을 48시간 처리하여 유도된 단백질의 존재를 전기영동을 통하여 확인하였다. 2. FPLC를 이용한 DEAE와 phenyl column을 이용하여 순수한 정제가 가능하였고, 이 과정을 통하여 전기영동상에서 단일 밴드를 나타내는 하나의 단백질을 정제하였다. 3. 이 단백질의 분자량이 64,000이라는 것을 Se-phdex-G 100 column chromatography를 통하여 확인하였다. 4. 이 단백질에 대한 단일 항체를 조제하여 고역가 항체를 분비하는 hybridoma 세포주 3개를 작성하고 isotype등 특성을 조사하였다.

• Corrosion Science and Technology
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• 제12권5호
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• pp.220-226
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• 2013

The uncertainty in statistical noise resistance measurement was evaluated for a type 316 stainless steel in NaCl solutions at room temperature. Sensitivity coefficients were determined for measurands or variables such as NaCl concentration, pH, solution temperature, surface roughness, inert gas flow rate and bias potential amplitude. The coefficients were larger for the variables such as NaCl concentration, pH, inert gas flow rate and solution temperature, and they were the major factors increasing the combined standard uncertainty of noise resistance. However, the contribution to the uncertainty in noise resistance measurement from the above variables was remarkably low compared to that from repeated measurements of noise resistance, and thus, it is difficult to lower the uncertainty in noise resistance measurement significantly by lowering the uncertainties related with NaCl concentration, pH, inert gas flow rate and solution temperature. In addition, the uncertainty in noise resistance measurement was high amounting to 17.3 % of the mean, indicating that the reliability in measurement of noise resistance is low.

• Corrosion Science and Technology
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• 제12권1호
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• pp.34-39
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• 2013

In this study, the effect of niobium addition on the passivation behavior of Ti alloys in NaCl solution was investigated using various electrochemical methods. An ${\alpha}$-phase in Ti alloy was transformed into a ${\beta}$-phase and martensite structure decreased as Nb content increased. The corrosion and passivation current density($+300mV_{SCE}$) decreased as Nb content increased, and thereby a stable passive film was formed on the Ti alloy. Potential of Ti-xNb alloy in the passive region increased, whereas, current density decreased with time from results of potentiostatic and galvanostatic tests. Also, the corrosion morphology showed the smaller pits as Nb content increased. Consequently, Ti alloy contained high Nb content showed a good resistance to pitting corrosion in 0.9% NaCl solution.