• Corrosion Science and Technology
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• 제19권6호
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• pp.281-287
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• 2020

Chloride ion is one of the most important corrosive agents in atmospheric corrosion, especially in marine environments. It has high adsorption rate and increases the conductivity of electrolytes. Since chloride ions affect the protective properties and the surface composition of the corrosion product, they increase the corrosion rate. A low level of chloride ions leads to uniform corrosion, whereas a high level of chloride ions may induce localized corrosion. However, higher solution temperatures tend to increase the corrosion rate by enhancing the migration of oxygen in the solution. This work focused on the effect of NaCl concentration and temperature on galvanic corrosion between A516Gr.55 carbon steel and AA7075T6 aluminum alloys. When AA7075T6 aluminum alloy was galvanically coupled to A516Gr.55 carbon steel, AA7075T6 was severely corroded regardless of NaCl concentration and solution temperature, unlike the corrosion properties of single specimen. The combined effect of surface treatment involving carbon steel and aluminum alloy on corrosion behavior was also discussed.

• Korean Chemical Engineering Research
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• 제44권5호
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• pp.535-539
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• 2006

가연성 폐기물 가스화반응으로 생성되는 합성가스내의 $CO_2$ 제거반응에서 $Li_2ZrO_3$와 알칼리염 첨가제의 효과를 열중량 분석기를 이용하여 그 특성을 연구하였다. $Li_2ZrO_3$는 고체상태의 $ZrO_2$와 $Li_2CO_3$를 합성하여 제조하였고, 반응성향상을 위하여 $K_2CO_3$, $Na_2CO_3$, NaCl, LiCl 등의 알칼리염을 첨가한 후 열처리하여 사용하였다. 첨가한 알칼리염에 따른 반응성 향상은 $K_2CO_3>NaCl>LiCl>Na_2CO_3$ 순으로 나타났고 이는 $Li_2CO_3$의 partial melting에 기인한 것으로 사료된다. 반응 시료의 SEM 분석 결과 용융상태의 존재를 확인할 수 있었고, XRD를 통해 첨가된 알칼리염들의 화학적 성분 변화는 일어나지 않는 것으로 확인되었다. NaCl을 사용한 경우 반응 초기에 60분 정도의 유도시간이 발생하였으며, $Na_2CO_3$가 첨가된 경우 $700{\sim}750^{\circ}C$에서도 $Li_2ZrO_3$의 $CO_2$ 제거반응에 의해 생성된 $Li_2CO_3$의 분해가 유도되지 않아 반응성 감소현상이 나타나지 않았다.

• 한국해양공학회지
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• 제6권1호
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• pp.140-147
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• 1992

Corrsion fatigue test was performed under rotated bending in 3.5% NaCl aqueous solution having a temperature from 278.deg.K in order to investigate the effects of aqueous solution remperature on the corrosion fatigue fracture of raw material steel(SS41) and dual phase steel that was produced from SS41 by a series of heat treatment. Corrosion fatigue life decreases remarkably with increase in solution temperature or with decrease in stress level. The corrosion fatigue life and the crack propagation rate at 303.deg.K show the similar behaviors with those at 318.deg.K, which is assumed to be caused by concentration polarization phenamena. The number and the lengths of microcracks increase with increase in solution temperature, so they lead to the decrease in corrosion fatigue life.

• 한국축산식품학회:학술대회논문집
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• 한국축산식품학회 2006년도 정기총회 및 제37차 춘계 국제학술발표대회
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• pp.219-223
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• 2006

In the current study, the addition of either NaCl or GdL Increased the binding strength and it considered that the use of GdL with or without low NaCl concentration improved the binding strength of restructured pork meat. Major deterioration of GdL addition is cooked-like discoloration. However, the combination with washing process or addition of carrageenan could improve cold-set binding properties of restructured pork, even if low NaCl or GdL were added.

• 한국식품영양학회지
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• 제33권4호
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• pp.419-427
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• 2020

The purpose of this study was to investigate the qualitative changes of the citron by identifying the type of solution and addition of the solution to prevent the browning reaction of the citron in a way that inhibits the browning of the citron. The browning inhibitor solution was investigated using the individual and mixture, and the results of the degree of browning and chromaticity showed that vitamin C+NaCl+cyclodextrin (CD) had the lowest browning of 0.52. In chromaticity, the ΔE values indicate that the higher the value, the greater the change in color, and the lowest value of the vitamin C+NaCl+CD mixture was 47.0, indicating that there was minimal browning compared to other treatment. The active change of the polyphenol oxidase (PPO) in the citron increased enzyme activity as the browning progressed, and the vitamin C+NaCl+CD solution was the lowest at 68.40 μ/g among the anti-browning solution. Based on these research results, it seems that the CD mixing solution can be used as a citron browning inhibitor.

• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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• 제4권1호
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• pp.51-57
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• 2000

Changes in the proline accumulation of ten-day-old seedlings of Vigna angularis in response to NaCl treatment were monitored. The proline content increased gradually both with an increase in the exposure time to salt stress and in a concentration-dependent manner. The increased proline accumulation was stronger in the shoots than in the roots. The salt stress by itself resulted in a significant inhibition of the chlorophyll content. Pre-treatment with proline before salinization lasting 48 h did not significantly affect the endogenous proline level in the roots, in contrast, a considerable increase of proline was observed in the shoots. The application of exogenous proline to the seedlings increased the endogenous proline content and improved the root and shoot growth under saline conditions. Detached leaves also exhibited an increased proline level in response to the applied NaCl, however, at a lower magnitude than in the intact seedlings. The proline alleviated the inhibitory effect of the NaCl in a concentration-dependent manner, thereby suggesting that salinity is a strong inducer of proline accumulation. In addition, abscisic acid eliminated the inhibitory effect of the salt salinity, thereby indicating a protective role on salinity stress and a regulatory role in proline synthesis. Accordingly, it would appear that proline may be involved in salt tolerance.

• 한국의류산업학회지
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• 제12권2호
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• pp.240-245
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• 2010

The effects of monazite and fixing agents on cotton fabric dyed with Perilla frutescens var. acuta extract were investigated. The proper monazite treatment concentration, temperature and time were 10%(o.w.b.), $50^{\circ}C$ and 60minutes. By various fixing agent treatment, $FeSO_4$ showed a relatively high K/S value and the order of K/S value decreased as follows, cation surface active agents, soybean and NaCl. And the monazite and $FeSO_4$ fixing agent showed higher anion emissity than those of untreated cotton and other fixing agents. The cotton fabrics showed improved color fastness by monazite and fixing agents treatments with the exception of light fastness. And the cotton fabrics fixed with fixing agents were showed effective bacterial reduction with the exception of NaCl.

• 한국자원리싸이클링학회:학술대회논문집
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• 한국자원리싸이클링학회 2003년도 추계정기총회 및 국제심포지엄
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• pp.122-128
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• 2003

To develop a Mg-Zeolite for simultaneous recovery of the N and the P from sewage water, the natural zeolite was treated with 20% $MgCl_2$ solution by changing the pH the temperature and the treating time of the solution. And the contents of Ca Fe Na K Mg of Mg-Zeolite were analyzed by ICP. The optimum treatment condition for Mg-Zeolite was induced to pH 7.0 $50^{\circ}C$ in 20% $MgCl_2$ solution and for 80min treatment. And the Na and the K ions in natural zeolite are significant factors for Mg exchange in the zeolite.

• 한국식품영양과학회지
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• 제29권2호
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• pp.218-223
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• 2000

The objective of this study was to investigate the effectiveness of preservatives for extending storage life and maintaining the quality of minimally processed Chinese cabbage. Cut Chinese cabbage was treated with either 1% CaCl2, 1% NaCl, 3% sucrose, 1% Ca-lactate, 1% vitamin C, 0.05% chitosan＋1% vitamin C, 0.1% Sporix＋1% vitamin C or hot water(6$0^{\circ}C$) and then packed with polyethylene film(60${\mu}{\textrm}{m}$) and stored at either 2$0^{\circ}C$ or 4$^{\circ}C$. To evaluate biochemical changes and quality of minimally processed Chinese cabbage, the samples were tested to determine the amount of vitamen C, titratable acidity, organic acid and fiber contents. Changes in color were also examined. The quality of kimchi prepared form minimally processed cabbage was affected by the treatments. REsults indicate that the minimally processed Chinese cabbage treated with either 1% CaCl2 at 2$0^{\circ}C$ and 4$^{\circ}C$ or 1% NaCl at 2$0^{\circ}C$ minimized biochemical changes in plant tissue and those treatments were most effective in maintaining product quality. The cabbage treated with 1% vitamin C or 1% NaCl at 4$^{\circ}C$ resulted in kimchi with improved color, texture, flavor and the best overall acceptability, as determined by a sensory test.

• 한국작물학회지
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• 제49권2호
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• pp.94-99
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• 2004

This study was conducted to determine the effect of salinity on the growth and development of Korean ginseng (Panax ginseng C.A.Meyer) and to evaluate the inorganic ion content in Korean ginseng with different general complete fertilizer (GCF) and NaCI concentrations at two growth stages. The stem height of Korean ginseng treated with different GCF and NaCI concentrations decreased at the higher EC (2.0 dS m$^{-1}$ ), but there were no significant difference in the stem diameter, the leaf length, and the leaf width among different treatments. The root growth increased with the supply of GCF. Especially, the root growth was facilitated two times at 3.0 dS $\textrm{m}^{-1}$ as compared to control. But the root growth more sharply decreased with NaCI treatment than GCF. The $\textrm{K}^{+}$ and $\textrm{Mg}^{2+}$ content in leaves and roots increased with GCF at the early growth stage. At the late growth stage, the $\textrm{K}^{+}$ content in leaves decreased but the $\textrm{Ca}^{2+}$ and $\textrm{Mg}^{2+}$ content increased. The $\textrm{Ca}^{2+}$ and $\textrm{Mg}^{2+}$ content in roots increased but the $\textrm{K}^{+}$ content decreased. The $\textrm{Na}^{+}$ content in Korean ginseng increased sharply with NaCl treatment. The $\textrm{NO}_3^{-}$ content in leaves and $\textrm{NH}_4^{+}$ content in leaves and roots increased as GCF concentration increased. The $\textrm{NO}_3^{-}$ content in leaves, stems, and roots at the late growth stage decreased as NaCl concentration increased. The $\textrm{NH}_4^{+}$ content in leaves and roots decreased significantly at the early growth stage, but it decreased significantly in leaves and stems at the late growth stage. The root activity of Korean ginseng increased with GCF, but decreased as the EC increased with NaCl. The water potential of leaves with GCF showed no significant difference compare to control, but the water potential of leaves treated with NaCl decreased as EC increased.