• Membrane Journal
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• v.11 no.1
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• pp.22-28
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• 2001

Various charged homogeneous membranes were fabricated by blending of ionic polymer with a non-ionic polymer with different ratios. In this study. sodium alginate, chitosan and poly(vinyl alcohol) were employed as anionic. cationic and non-ionic polymers, respectively. The permcation and separation behaviors of aquCOll::; salt solutions have been investigated through the charged membranes. As the content of ionic polymer increases in the membrane, the hydrophilicity of the membrane increases and pure water flux as well as solution flux increases correspondingly, indicating that the permeation performance through the membrane is cletemunecl mainly by its hydrophilicity-, Electrostatic interaction between the charged membrane and ionic solute molecules, that is. Donnan exclusion was observed to be attributed to salt rejection to a great deal of extent, and molecular sieve mechanism was effective [or the separation of the salt solution under a similar electrostatic circumstance of solutes.

• Bulletin of the Korean Chemical Society
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• v.34 no.12
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• pp.3602-3608
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• 2013

Saccharomyces cerevisiae, which is a common species of yeast, is by far the most extensively studied model of a eukaryote because although it is one of the simplest eukaryotes, its basic cellular processes resemble those of higher organisms. In addition, yeast is a commercially valuable organism for ethanol production. Since the yeast data can be extrapolated to the important aspects of higher organisms, many researchers have studied yeast metabolism under various conditions. In this report, we analyzed and compared metabolites of Saccharomyces cerevisiae under salt and pH stresses of various strengths by using two-dimensional NMR spectroscopy. A total of 31 metabolites were identified for most of the samples. The levels of many identified metabolites showed gradual or drastic increases or decreases depending on the severity of the stresses involved. The statistical analysis produced a holistic outline: pH stresses were clustered together, but salt stresses were spread out depending on the severity. This work could provide a link between the metabolite profiles and mRNA or protein profiles under representative and well studied stress conditions.

• Korean Journal of Community Nutrition
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• v.15 no.5
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• pp.670-678
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• 2010

Recognition thresholds for NaCl, sucrose, citric acid, and caffeine, as well as the pleasant concentration of NaCl were assessed in 176 males and 312 females aged 50-88 years. Furthermore, relationships among taste sensitivities, taste preferences, and lifestyles were examined. The taste solutions were presented one after the other in ascending order using the sip-and-spit method. For the recognition thresholds of the 4 basic tastes, women perceived significantly lower concentrations than the men. However, the pleasant concentration of NaCl did not show a gender difference. Sensitivities for the 4 basic tastes did not decrease with age in the men, but they did significantly decrease with age for the women, especially for those above 70 years. For men, regular exercise was positively correlated with sensitivities for sour taste and bitter taste, and physical activity was negatively correlated with the pleasant concentrations of NaCl. For women, who had more physical activity, sensitivities for sweet taste and sour taste were lower compared to the others. This study indicates that the sensitivities for 4 basic tastes in water diminished with age, but pleasant salt concentration did not change with age. Further research on pleasant NaCl concentration is required to determine factors affecting salt preference, in order to decrease salt intake in the elderly.

• Journal of the Korean Society of Food Culture
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• v.30 no.3
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• pp.249-266
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• 2015

The sauce and paste, which is collectively called as 'jang' in Korean is the staple seasoning of Korean cuisine. Although China shares some aspects of the Jang (醬), the exact types and forms are different. In this study, we explore the current Korean jang through the six culinary books- "Seongwonlog (醒園錄)", "Yangsolog (養小錄)", "Jojeongjip (調鼎集)", "Susiggeeumsigbo (隨息居飮食譜)", "Junggwerok (中饋錄)", and "Sosigseolyag (素食說略)" from the Qing Dynasty of China. The Jang of Qing Dynasty are further classified into the Chumjang (甛醬), Dusi (豆豆支), Chungjang (淸醬), and jangyou (醬油). To make these four types, the huangzi (黃子) has to be first made from the flour or beans, after which salt is added and sun-dried. Chumjang is the type of Chunjang used to make Zhajiangmian and is widely used in the Northern part of China. Like Chumjang, Dusi is made from flour and beans. Salt as well as various spices like Star anise, Chinese pepper and sesame are added. This type of paste is widely used in the Southern part of China. Chungjang is made when salt and water are added and sun-dried, after which it is filtered through an apparatus called Jangyou. The final product is sauce similar to today's soybean sauce.

• Macromolecular Research
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• v.13 no.6
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• pp.483-490
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• 2005

A novel, polysaccharide-based, superabsorbent hydrogel was synthesized through crosslinking graft copolymerization of methacrylic acid (MAA) onto kappa-carrageenan ($_{k}C$), using ammonium persulfate (APS) as a free radical initiator in the presence of methylenebisacrylamide (MBA) as a crosslinker. A proposed mechanism for $_{k}C$­g-polymethacrylic acid ($_{k}C$-g-PMAA) formation was suggested and the hydrogel structure was confirmed using FTIR spectroscopy. The effect of grafting variables, including MBA, MAA, and APS concentration, was systematically optimized to achieve a hydrogel with the maximum possible swelling capacity. The swelling kinetics in distilled water and various salt solutions were preliminarily investigated. Absorbency in aqueous salt solutions of lithium chloride, sodium chloride, potassium chloride, calcium chloride, and aluminum chloride indicated that the swelling capacity decreased with increased ionic strength of the swelling medium. This behavior can be attributed to the charge screening effect for monovalent cations, as well as ionic crosslinking for multivalent cations. The swelling of super absorbing hydrogels was measured in solutions with pH ranging from 1 to 13. In addition, the pH reversibility and on-off switching behavior, at pH levels of 3.0 and 8.0, give the synthesized hydrogels great potential as an excellent candidate for the controlled delivery of bioactive agents.

• Journal of Surface Science and Engineering
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• v.26 no.2
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• pp.55-62
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• 1993

The effect of interlayer coating thickness of Ni and Ti on corrosion behavior was studied for TiN ion plat-ed steel plate. Interlayer coating was carried out in a single and bi-layer to a various thickness combination prior to final TiN coating. Corrosion behavior was evaluated by anodic polarization test in 1N H2SO4 as well as salt spray test. Ni interlayer coating was effectived in reducing corrosion current density of active region and Ti interlayer coating over Ni coating reduced the anodic corrosion current density by an order of 4 with increasing the thickness of Ti up to$ 3\mu\textrm{m}$. The improvement of corrosion resistance by Ni/Ti interlayer coating was attributed to the effective prevention of penetration of active corrosion agent resulting from the inherent corrosion resistance of Ni and Ti. Putting corrosion behavior was observed from salt spray test result for all specimens and corrosion resistance at salt atmosphere was enhanced with increasing Ni and Ti thickness, Cor-lay TiN coating was spalled out by the generation of corrosion products.

• Corrosion Science and Technology
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• v.7 no.6
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• pp.370-374
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• 2008

In this study, we evaluated anti-corrosion properties of both commercial unleaded and lead epoxy primer for automotive substrate before applying to actual painting lines by salt spray test, and cyclic corrosion test, potentiodynamic test and electrochemical impedance spectroscopy. The difference in the corrosion resistance between automotive epoxy primers contained $Bi(OH)_{3}$ and leaded one was investigated. And it was also discussed the effect of zinc phosphate pretreatment to the epoxy primers. The specimen coated epoxy primer contained $Bi(OH)_{3}$ showed 0.5 V higher corrosion potential than that of bare steel. The result of salt spray test did not indicate remarkable difference of corrosion resistance in all specimens above $10{\mu}m$ thickness up to 1200 hours. In the cyclic corrosion test, epoxy primers contained $Bi(OH)_{3}$ on phosphated substrate performed good corrosion properties until 800 hours. The epoxy primer contained $Bi(OH)_{3}$ performed the equivalent corrosion resistance as leaded coating on phosphated steel, but slightly inferior to that of leaded on bare steel. These results show that the pre-treatment of zinc phosphate is effective as well as pigment changing in performing anti-corrosion properties in automotive bodies.

• Corrosion Science and Technology
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• v.16 no.2
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• pp.59-63
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• 2017

Chelating solutions can be damaged by strong acids during oil production. To design effective corrosion inhibitors and other alternatives for corrosion control, it is important to understand not only the behavior of the system under operating condition but also the kinetics of electrochemical reactions during the corrosion process. In this study, the electrochemical behaviors of P-110 steel in aqueous fluids based on ethylenediaminetetraacetic acid (EDTA) compounds under various temperatures and hydrodynamic regime conditions were assessed. Electrochemical measurements were conducted using rotating disc electrodes manufactured. Electrolytes were prepared using aqueous compounds of EDTA like diammonium salt, disodium salt, and tetrasodium salt. Potentiodynamic polarization, electrochemical impedance, and mass loss tests were performed in order to assess the corrosion kinetic in electrolytes. Hydrodynamic effects were observed only in the cathodic polarization curve. This proves that hydrodynamic regime plays an important role in the corrosion of steel mainly in disodium and diammonium EDTA solutions. Two cathodic reactions controlled the corrosion process. However, oxygen level and pH of the electrolyte played the most important role in metal corrosion. Corrosion rates in those fluids were decreased drastically when oxygen concentration was reduced.

• Journal of The Korean Society of Grassland and Forage Science
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• v.10 no.2
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• pp.77-83
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• 1990

A three year's field experiment was carried out on newly reclaimed tidal saline soils to evaluate the salt tolerance and growht characteristics, and their relationship to dry matter production and nutrient quality of main selected pasture species. Nine temperate grasses (14 varieties) and two forage crops (sorghum and pearl millet) were grown under different mulching treatments with medium sand and red-yellow soils (fine loamy materials of Typic Hapludults) from 1986 to 1988. Tall wheatgrass, tall fescue, reed canarygrass and alfalfa showed a good tolerance to soil salinity, especially tall wheatgrass (cv. Alkar) produced 19.6 ton/ha dry matter yield annualy under mulching treatment with medium sand depth in lcm. Pearl millet (cv. Gahi-3) was also evaluated as a salt tolerable forage species. Under salt stress in newly reclaimed tidal lands, plant showed a decrease in the assimirable leaf area (LA) as well as specific leaf area (SP. LA) and a low leaf weight ratio(LWR), and it resulted in a low concentration of crude protein and low digestible dry matter contents. Absorption of macro and micro elements in the plant on tidal lands was increased markedly.

• Journal of the Korean Society of Clothing and Textiles
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• v.48 no.5
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• pp.823-839
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• 2024

As environmental awareness increases, more consumers are opting for eco-friendly detergents. Detergents can enhance washing, but an excessive amount does not significantly improve results. Inadequate rinsing can also cause skin irritation and water pollution. Eco-friendly laundry additives commonly include baking soda, sodium percarbonate, citric acid, salt, and effective microorganisms (EMs). In consideration of these issues, this study examined how eco-friendly laundry products affect washing efficiency. We evaluated the pH and washability of these products and detergent solutions using cloths contaminated with sebum or protein. When combined with heavy-duty or multipurpose detergent, baking soda, citric acid, and EMs exhibited decreased pH levels, thereby impacting washing effectiveness. Citric acid was less effective than water alone. Salt did not affect pH or cleaning, but sodium percarbonate slightly improved the cleaning of protein-soiled fabric. Among neutral detergents, baking soda or sodium percarbonate increased pH and cleaning power, whereas citric acid, salt, and EMs had minimal impact. Protein-contaminated cloths were washed well with sodium percarbonate alone. EMs were more effective than citric acid but not enough for them to count as detergent replacements. Lipid-contaminated cloths were ineffectively washed with laundry aids alone.