• Textile Coloration and Finishing
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• v.4 no.3
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• pp.65-73
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• 1992

To control the hydrolysis rate of PET fabric with NaOH, HCl and $CH_3$COOH(HAc), as regulating reagent, were added to the 0.5 M NaOH solution. The concentrations of acids in 0.5 M NaOH were varied. PET fabrics were treated with aqueous solutions of acids in 0.5 M NaOH under different conditions. The weight loss of PET fabric, the rate of hydrolysis, the apparent activation energy (E$_{\alpha}$), the handle value, the etched surface of treated PET fabric, and the effect of salts such as NaCl, $CH_3$COONa(NaAc), and NH$_4$Cl on the weight loss were discussed. Acids in the aqueous 0.5 M NaOH solution decreased the weight loss of PET fabric bacause of neutralization of OH- and the weight loss of PET fabrics treated with corresponding concentration of aqueous NaOH solution to the concentrations of the aqueous solutions of acids in 0.5 M NaOH was lower than that of PET fabrics treated with aqueous solutions of acids in 0.5 M NaOH. The addition of NaCl to aqueous NaOH solution accelerated the reaction of OH- with PET greatly, the addition of NaAc increased the weight loss slightly, but the addition of NH$_4$Cl decreased the weight loss. It was thought that the very remarkable result that NaCl in aqueous NaOH solution promoted the hydrolysis of PET with NaOH would contribute to the conservation of energy and NaOH in the weight loss finishing process of PET fabric. The etched surface and the handle value of treated PET fabric were independent of the difference in the kinds of acids and salts added.nd salts added.

• Korean Journal of Environmental Agriculture
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• v.18 no.1
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• pp.61-65
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• 1999

This study was conducted to obtain the basic information on saline tolerance of plants. Fourteen plant species were grown under different salinity adjusted with NaCl. After 14 days treatment, physiological changes were investigated. Proline contents of tested plants were increased as salinity was increased. Acalvpha australis, Bidens bipinnata, Erechitites hieracifolia, Erigeron canadensis, Punicum dichotomiflorum, and Solanum nigrum showed drastic increase of proline contents in 200mM NaCl treatment. But Atriplex gmelini, Suaeda asparagoldes did not show drastic increase. As the NaCl concentration increased to 200mM in media, both contents of $Na^+$ and $Cl^-$ were increased. Acalypha australis, Digitaria sanguinalis, Erechitites hieracifolia, and Solanum nigrum showed drastic increase in $Na^+$ and $Cl^-$ contents under 200mM NaCl. But Suaeda asparagoides. Atriplex gmelini, and Spergularia marina were slightly increased. As salinity increased, the $K^+/Na^+$ ratio of halophytes, such as Suaeda asparagoides, Atriplex gmelini, and Spergularia marina were more slightly decreased than glycophytes.

• Korean journal of food and cookery science
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• v.13 no.5
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• pp.569-577
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• 1997

The characteristics of an watery type Kimchi prepared without the addition of red pepper, were investigated focused on the effect of salt concentration and fermentation temperatures. The Chinese cabbage was brined in various NaCl solution to obtain the final salt concentration range of 0.5∼3.0% of the brined cabbage. Fermentation of Baik Kimchi was carried out at 10, 20, 30$^{\circ}C$ with addition of equal weight of water to brined cabbage. The result showed that the fermentation was generally increased as the NaCl concentration decreased for all temperatures based on the data of pH and total acidity. The higher temperature resulted in an increase in fermentation rate in terms of pH and total acidity. The organoleptic flavor properties of fresh sourness and acidity were significantly affected by NaCl concentration and fermentation temperatures. The Baik Kimchi prepared with 1.0% NaCl and fermentation at 30$^{\circ}C$ was found to be most acceptable.

• Korean journal of food and cookery science
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• v.6 no.2
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• pp.1-6
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• 1990

The purpose of this study was to investigate the effects of preheating and salt concentration on the fermentation rate and firmness of cucumber kimchi, and the relationship between firmness and the contents of pectin fractions, hemicellulose and cellulose during fermentation. For this purpose, pH, acidity, firmness and the contents of pectic fractions, hemicellulose and cellulose were studied. 1. The changes of pH and titratable acidity indicated that preheating and high salt concentration delayed the fermentation rate in cucumber kimchi. 2. After 9 days, preheated cucumber kimchi was firmer than nonpreheated cucumber kimchi. 3. During fermentation, the cucumber kimchi fermented at 5% NaCl was firmer than that femented at 2% NaCl. 4. After 9 days, preheated cucumber kimchi was higher in insoluble pectin (HCISP)content and lower in soluble pectin (HWSP & HXSP) content than nonpreheated cucumberkimchi and hese results in accord with those of firmness measurements. 5. During fermentation, the cucumber kimchi fermented at 5% NaCl was higher in insoluble pectin content and lower in soluble pectin content than nonpreheated cucumber kimchi, and these results were in accord with those of firmness measurement. 6. During fermentation, cellulose content decreased.

• Geophysics and Geophysical Exploration
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• v.7 no.1
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• pp.99-104
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• 2004

A combination of drilling, geophysical well logging, and electrical soundings was performed to evaluate seawater intrusion in Baeksu-eup, Youngkwang-gun, Korea. The survey area extends for over 24 $km^2$. To delineate the extent of seawater intrusion, 60 vertical electrical soundings (VES) have been carried out. Twelve wells were also drilled for the collection of hydrogeological, geochemical, and geophysical well logging data, to delineate the degree and vertical extent of seawater intrusion. To map the spatial distribution of seawater in this coastal aquifer, geophysical data and hydrogeochemical results were used, and the relation between the resistivity of groundwater and equivalent NaCl concentration was found. Layer parameters derived from VES data, various in-situ physical properties from geophysical well logging, and the estimated equivalent NaCl concentration were very useful for quantitative evaluation of seawater intrusion. Our approach for evaluating seawater intrusion can be considered a valuable attempt at enhancing the use of geophysical data.

• 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 Microbiology
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• v.42 no.2
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• pp.156-159
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• 2004

In general, the salinity of the ocean is close to 3.5％ and marine vibrios possess the respiratory chain-linked Na$\^$+/ pump. The influence of sodium chloride and the proton conductor carbonylcyanide m-chlo-rophenylhydrazone (CCCP) on the production of extracellular proteases in a marine Vibrio strain was examined. At the concentration of 0.5 M, sodium chloride minimally inhibited the activity of extra-cellular proteases by approximately 16％, whereas at the same concentration, the producton of extra-cellular proteases was severely inhibited. On the other hand, the production of extracellular proteases was completely inhibited by the addition of 2 ${\mu}$M CCCP at pH 8.5, where the respiratory chain-linked Na$\^$+/ pump functions.

• Journal of Soil and Groundwater Environment
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• v.13 no.1
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• pp.13-23
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• 2008

The triaxial compression tests and consolidation tests using NaCl solution and leachates as substitute pore (or saturated) water in samples were carried out to find out the behavior characteristics of strength, deformation and permeability coefficient of contaminated clay. Also, the chemical property analysis on the clay samples using scanning electron microscope and energy dispersive x-ray spectrometer were involved. The magnitudes of composition ratio were shown in the order of O, C, Si, Al, and Fe as a result of chemical composition analysis for clay samples. Besides, as the results of triaxial compression tests and consolidation tests, the shear strength, compression and permeability properties were increased with increasing in the concentration of contaminant (NaCl). It may be considered that these circumstances be caused by the changes of soil structure to flocculent structure due to the decrease in the thickness of diffuse double layer with increasing in the concentration of electrolyte. MT3D model was also using to grasp the procedures that the groundwater may be contaminated by the leachates permeated through the clay liner. The results of contaminant transport analysis showed a tendency that the predicted concentration of groundwater was higher with increasing in the initial concentration of $Cl^-$ ion and increased as a nonlinear curves with time. The transportation distance calculated by the use of regression equation between the distance from contaminant source and the concentration of $Cl^-$ ion was increased with increasing the initial concentration.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.1
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• pp.114-118
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• 1997

Effect of water temperature, salt and $MgCl_2$ concentration on sand ejection characteristics of short neck clam, Luditapes philippinarum was investigated. Unlike other shell fish such as red shell, arkshell and surf clam, treatment of short neck clam with sea water was evaluated not effective as sand ejection conditions. Sand ejection activity of short neck clam was shown effective at $2.5\%$ NaCl (pH 8.0) at $25^{\circ}C$. This activity was enhanced about 1.57 times when 50 mM $MgCl_2$ were added to the above mentioned conditions. But the extent of sand ejection activity was shown higher in the order of sea water $(3.2\%\;salt)+20mM\;MgCl_2$, sea water $(3.2\%\;salt),\;2.5\%\;NaCl+50mM\;MgCl_2$, treatments. Therefore, it was suggested that habitat conditions and Mg ions could be responsible for biological activity and concominant sand ejection of short neck clam.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.38 no.5
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• pp.391-397
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• 1993

Rye(Secale cereale cv. Chunchu), barley(Hordeum vulgare cv. Dusan 29#), and italian ryegrass(Lolium multiflorum cv. Barmultra) were treated at 0, 0.1, 0.3, and 0.6 % of NaCl solution for 30 days. Plant height, leaf length, and leaf area were decreased with increasing NaCl level, and leaf area was decreased mainly due to decrease of leaf length. Root length was decreased at higher NaCl levels, but root number was increased. Shoot dry weight was decreased by increasing NaCl levels in rye and italian ryegrass, but barley did not show significant change. Dry weight of root was more decreased than that of shoot at higher NaCl levels. Chlorophyll content was decreased, but electric contuctivty of shoots and roots was increased at higher NaCl levels. Na+ content in shoot and root was increased with increasing NaCl level but the degree was not same. Reducing power of roots was that three crops as affected by NaCl was not equal. Barley was the most tolerant to NaCl stress.