• Tribology and Lubricants
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• v.20 no.2
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• pp.91-96
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• 2004

Wear behavior of self-mated stainless steels in NaCl solution has been investigated. The experiment was done in the corrosive liquid of which NaCl concentration of $0\~3\%$ and temperature of $15\~90^{\circ}C$. Two kinds of wear type were observed: one is 'severe wear' type which shows gradually increasing wear volume with increasing sliding distances, the other is 'mild wear' type which shows change of wear rate from high value to low at transition distance. The specific wear rate in severe wear type was not sensitive to the liquid temperature and concentration of NaCl but stable at value of $1\times10^{-3}\;mm^3$ approximately.

• Transactions of the Korean Society of Mechanical Engineers
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• v.14 no.2
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• pp.399-406
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• 1990

This paper is studied to know corrosive wear mechanism of STS304 steel on atmospherical temperature against mating material as the same. The corrosive test was carried out by rubbing the annular surface of two test pieces in distilled water and NaCl aqueous solution. The corrosive wear mechanism was investigated by S.E.M. The experimental results show that there is one Lcr transferring from severe wear to mild wear on change of NaCl concentration and atmospherical temperature, and which is the other still remaining in server wear state. It was found that the critical sliding distance Lcr shorten with increasing NaCl concentration but it is longer with ascending atmospherical temperature and the mild wear state still continues under the condition of high generation rate and elimination rate of the corrosive product. Considering upon the result, the model of corrosive wear mechanism is proposed.

• Microbiology and Biotechnology Letters
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• v.39 no.3
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• pp.294-300
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• 2011

Proteolytic bacteria were isolated from Myeolchi-jeotgal and Saeu-jeotgal using high-salt-content media and their growths in the media containing 25% NaCl were monitored to draw the role of bacteria in the ripening of jeotgal. The most populous genus in Myeolchi-jeotgal detected on agar media with 15% NaCl was Bacillus and its relatives, while the most populous in Saeu-jeotgal was Staphylococcus. Among the isolates, Virgibacillus halodenitrificans from Myeolchi-jeotgal and Halobacillus trueperi from Saeu-jeotgal showed proteinase activities. The species from Myeolchi-jeotgal showed proteinase activity on the agar media with 8% NaCl were similar to those isolated from the media with 15% NaCl. The dominant of Myeolchi-jeotgal isolated at the 15% NaCl concentration may be involved in the proteolysis. The proteolytic species from Saeu-jeotgal on the agar media with 8% NaCl were the genera Bacillus, Salinicoccus, and Salimicrobium those were not the dominants at 15% NaCl condition. The dominant isolates from Saeu-jeotgal on agar media with 15% NaCl may not be involved in the proteolysis of Saeu-jeotgal. Vb. halodenitrificans and Staphylococcus equorum, the dominant species from Myeolchi-jeotgal and Saeu-jeotgal, showed growths at the nutrient broth containing 25% NaCl. They may play a significant role in the ripening of jeotgal and have a high possibility to be used as the starter.

• Horticultural Science & Technology
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• v.31 no.5
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• pp.617-625
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• 2013

Stauntonia hexaphylla and Raphiolepis indica, cold-tolerant broadleaved evergreens ranging through the southern region of South Korea, were assessed on salt tolerance with NaCl treatment using visual damage, chlorophyll florescence image, and malondialdehyde (MDA) analysis. As NaCl concentrations increased, the soil pH decreased and EC increased, and the soil of S. hexaphylla was affected more strongly by the treatment than that of R. indica. In visual damage, S. hexaphylla withered above 200 mM NaCl at 20 days after the treatment. All individuals of R. indica survived during the experiment though the leaves of R. indica showed visual damages up to 400 mM NaCl. The color changes in chlorophyll fluorescence showed a strong correlation with the degree of visual damage. As NaCl increased, the red color of the leaves of S. hexaphylla was distinctly changed to blue and chlorophyll fluorescence decreased starting from the margin to the middle of a leaf. R. indica showed subtle color changes and remained in red color during the experiment. At five days after the NaCl treatment, the MDA of S. hexaphylla was above $4.56nmol{\cdot}g^{-1}$ when plants showed the highest visual damage and EC. The MDA of R. indica in all treatments showed below $1.5nmol{\cdot}g^{-1}$ except 400 mM NaCl treatment during the experiment.

• Korea-Australia Rheology Journal
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• v.15 no.3
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• pp.151-156
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• 2003

In this research, experimental studies were performed to examine the rheological behavior of equimolar solutions of cetylpyridinium chloride (CPyCl) and sodium salicylate (NaSal) solutions with concentration. The surfactant solutions were prepared by dissolving 2 mM/2 mM - 80 mM/80 mM of surfactant/counterion in double-distilled water. It has been observed that the zero shear viscosity shows abrupt changes at two critical values of C^*$ and C^{**}$. These changes are caused by the switching of relaxation mechanism with concentration of CPyCl/NaSal solutions at those concentrations. The wall slip velocities of dilute and semidilute CPyCl/NaSal solutions show a dramatic increase with shear rate where the shear viscosity exhibits shear thickening behavior for dilute solutions and shear thinning behavior for semi-dilute solutions, respectively. Considering that the dramatic increase in wall slip velocity should be related to the formation of shear-induced structure (SIS) in the surfactant solution, the shear thickening behavior of semi-dilute solutions is caused by elastic instability unlike the case of dilute solutions.

• BMB Reports
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• v.35 no.3
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• pp.306-312
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• 2002

The effects of salts on the biochemical properties of D-amino acid aminotransferase from Bacillus sp. YM-1 have been studied to elucidate both the inhibitory effects of salts on the activity and the protective effects of salts on the substrate-induced inactivation. The results from UV-visible spectroscopy studies on the reaction of the enzyme with D-serine revealed that salt significantly reduced the rate of the formation of the quinonoid intermediate and its accumulation. The kinetic and spectroscopy studies of the reaction with $\alpha$-[$^2H$]-DL-serine in different concentrations of NaCl provided evidence that the rate-limiting step was changed from the deprotonation of the external aldimine to another step(s), presumably to the hydrolysis of the ketimine. Gel filtration chromatography data in the presence of NaCl showed that the enzyme volume was reduced sharply with the increasing NaCl concentration, up to 100 mM. An additional increase of the NaCl concentration did not affect the elution volume, which suggests that the enzyme has a limited number of salt-binding groups. These results provide detailed mechanistic evidence for the way salts inhibit the catalytic activity of D-amino acid aminotransferase.

• KSBB Journal
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• v.17 no.6
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• pp.509-514
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• 2002

Experiments were carried out to optimize the fermentation conditions for the production of erythritol by salt-tolerant mutant, Candida magnoliae M26. The optimum conditions of erythritol production showed a 1.0 vvm aeration and 500 rpm agitation at 28$\^{C}$ with an initial medium pH of 7.0. The pH control during the fermentation did not improve the erythritol yield and productivity. The maximum erythritol concentration of 143.3 g/L was obtained with 57% yield and 0.70 g/L-h productivity from 250 g/L of glucose and 5 g/L of yeast extract under an optimum fermentation conditions. The medium containing 0.5 M KCl or 0.5 M NaCl enhanced the production of erythritol and glycerol. However, glycerol production increased and erythrtiol production decreased by increasing the concentration of NaCl or KCl.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.1
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• pp.131-136
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• 2004

The effects of salt concentration and heating conditions on the thermal gelation properties of surimi produced from mechanically deboned chicken meat (MDCM) were investigated. Chicken surimi was manufactured by washing (MDCM: 0.5% NaCl=1:4), standing, straining and centrifuging. The fat, water-soluble protein and heme pigment in the MDCM were removed by increasing washing cycles. The compressive force of the chicken surimi increased as the concentration of salt was increased from 0% to 5%. Total gel strength of the surimi measured by texture profile analysis showed a maximum in the range 3-5% NaCl. Microstructural analysis showed that the unfolding network structure of the surimi gel began to appear at NaCl concentrations>2%. The optimum heating condition for gelation was $90^{\circ}C$ for 40 min as this resulted in maximum values for measures of gel strength including compressive force, hardness, fracturability, adhesiveness, springiness, gumminess, chewiness and resilience. Chicken surimi gel formed by cooking at a heating rate of $1^{\circ}C/min$ to $90^{\circ}C$ showed better a texture than gels produced at $1.85^{\circ}C/min$. Our result show that a lower rate of heating improves chicken surimi gelation.

• Corrosion Science and Technology
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• v.3 no.5
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• pp.194-197
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• 2004

The corrosion resistance of several kind of ME (Metal Evaporated) tape has been investigated both in mild sulfuric acid solution and NaCl solution by electrochemical impedance spectroscopy. It was found that the degradation of ME tapes was accelerated with increasing the concentration of sulfuric acid. There was no significant change in corrosion resistance when the concentration of NaCl was under 3.5 wt%. However, the impedance value decreased when the concentration of NaCl was up to 10 wt%. The degradation of backside of ME tapes was also investigated by AC impedance measurements. The results showed that the impedance behavior of backside plastic film changed with the concentration of sulfuric acid even at the beginning of immersion, implying the changing of the permeability for the backside of ME tapes. It was also found that the corrosion resistance of DVC (Digital Video Cassette) ME tape was better that that of Hi-8mm ME tapes in sulfuric acid solutions. Also, the backside of DVC ME tape showed better water resistance than that of Hi8 ME tapes.

• Korean Journal of Environment and Ecology
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• v.30 no.5
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• pp.810-820
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• 2016

This study is focused on the investigation of the genes which are induced by various stresses of the halophyte Salicornia herbacea. One of the factors influencing in the germination of Salicornia herbacea is salt stress. The highest germination rate was found in the condition without NaCl, and the upper limit of the NaCl concentration for the germination of Salicornia herbacea was 7%. The optimal temperature of $20^{\circ}C$showed a germination rate of 98%. Among genes induced by stress the 2CysPrx gene was cloned and analyzed for this study. The 2CysPrx gene has two cysteine conserved residues and is composed of 275 amino acids with molecular weight of 30.1kDa. The 2CysPrx gene appeared to be one copy in the genome and consists of 6 introns and 7 exons. Quantitative real-time PCR revealed that the highest transcription rate induced by NaCl and $H_2O_2$ appeared to be at the concentration of 3.5% NaCl and 40mM $H_2O_2$, respectively. The amount of transcript induced by high temperature($40^{\circ}C$) and $75{\mu}M$ of ABA was respectively highest. The gene at low temperature ($4^{\circ}C$) appeared not to be expressed. We are conducting to clone other peroxyredoxin genes induced by various environmental stresses.