• Journal of the East Asian Society of Dietary Life
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• v.5 no.3
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• pp.287-298
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• 1995

This study was undertaken to examine the effect of salting in 10% salt solution added 2% calcium chloride on the kimchi fermentation. The addition of calcium chloride extended edible periods of the Kimchi to 4~5 days and increased relatively the hardness of Chinese Cabbage. In the addition of calcium chloride, the activities of amylase and $\beta$ -galactosidase were not high during all periods fermentation. Polygalacturonase and protease activities were low 2~21%, 2~26% all periods fermentation, respectively. There were significant correlations between the delay of ripeness and decreasing enzyme activation. The amount of free amino acid by the treatment with calcium chloride was decreased of 10~16% at the late of fermentation than that of control. the treatment with calcium chloride of the Kimchi was increased hardness, but decreased cohesiveness and gumminess was during all periods fermentation. the adhesiveness was increased at the early of fermentation but decreased at the late of fermentation.

• Food Science and Preservation
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• v.19 no.6
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• pp.813-817
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• 2012

The effects of dip treatments of chemicals (ascorbic acid, cystein, sodium chloride, magnesium chloride, calcium chloride, histidine: 1% solution) and medicinal herbs (Pueraria thunbergiana, Angelica gigas, Dioscorea japonica, Lindera strychifolia, Cnidium officinale, Astragalus membranaceus: 1% extracts), heat shock ($40-60^{\circ}C$ water), and edible coating (albumin, dextrin, sucrose poly ester, whole soy flour: 0.5-4% solution) on the browning degree of fresh-cut 'Fuji' apples were studied. Among the each treatment methods, the surface browning of fresh-cut apples was best retarded by calcium chloride dip, Astragalus membranaceus dip, $45-50^{\circ}C$ heat shock, coating with 3% dextrin or 1% whole soy flour. The results suggest that the treatments of medicinal herbs extracts, heat shock, and edible coating can be used as alternative for the use of chemical agents for the antibrowning of fresh-cut apples.

• Applied Chemistry for Engineering
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• v.5 no.4
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• pp.646-656
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• 1994

The ${\omega}$-formyl carboxylic acid was produced by ozone oxidation of cycloolefins in the presence of pyridine and its production yield was examined by varying temperature and solvent. As the reaction temperature increased, the yield of ${\alpha}$, ${\omega}$-dicarboxylic acid increased whereas that of ${\alpha}$, ${\omega}$-dialdehyde decreased. As the polarity of solvent increased, a higher yield of desired ${\omega}$-formyl carboxylic acid was obtained, whereas the yield of unwanted polymeric ozonide decreased. The yields of ${\omega}$-formyl carboxylic acid from ozone oxidation of cyclohexene, cyclooctene and cyclododecene at $0^{\circ}C$ and in methylene chloride solvent were 59.30%, 55.20%, and 36.72%, respectively.

• Korean Journal of Food Science and Technology
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• v.21 no.3
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• pp.370-374
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• 1989

This study was conducted to examine the effects of salt concentrations (1,2 and 37)) and storage periods on the characteristics of Kakdugi (Korea seasoned pickles of cubed radish roots) stored at $20^{\circ}C$. The sensory characteristics, pH, titratable acidity, non-volatile organic acids were measured. The results of sensory evaluation on Kakdugi containing 1,2 or 30% sodium chloride stored for 4 or 8 days indicated that there were significant differences among them expecially ill firmness, crispness and salty taste. As storage period increased, titratable acidity, sour taste, non-volatile organic acid contents of the samples increased. The changes were greater in Kakdugi with 2% sodium chloride. Major non-volatile organic acids were identified as lactic acid, citric acid and succinic acid. The sour taste of Kakdugi was closely related to the contents of non-volatile organic acid and titratable acidity.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.31 no.3
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• pp.255-265
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• 2021

Objectives: The purpose of this study is to analyze the exposure characteristics of inorganic acids. Methods: We analyzed exposure data (n = 363,146) for six inorganic acids (hydrogen fluoride, hydrogen bromide, hydrogen chloride, phosphoric acid, nitric acid, and sulfuric acid) collected between 2017 and 2019 in South Korea. Measurement characteristics and exposure levels (ELs) were analyzed by inorganic acid, industry category, enterprise size, and measurement year. Results: Measurement percentage dominated in time-weighted average (TWA, 91%) compared to short term exposure limit (STEL) and Ceiling. Most of the measurements (79.7%) were collected from the manufacturing category of industry. Medians of ELs were mostly low (≤3% of the threshold limit), with the exception of sulfuric acid (4.6% of TWA and 10.5% of STEL). The percentages of exceeding 1% of the occupational exposure limits (OELs) in TWA were relatively high for sulfuric acid (35.8%) and hydrogen chloride (16.5%) compared to the other acids (4.2%-6.6%). In addition, the percentages of exceeding 1% of OELs in STEL or Ceiling were higher for sulfuric acid (22.9%), hydrogen chloride (12.3%), and nitric acid (8.2%) compared to the other acids (1.2%-1.9%). The small-sized enterprises showed higher ELs in TWA; contrarily, the large-sized enterprises had higher ELs in STEL or Ceiling. Conclusions: The measurement characteristics and ELs identified in this study could be useful for establishing safety and health policies for inorganic acids.

• YAKHAK HOEJI
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• v.30 no.6
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• pp.294-300
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• 1986

New antibiotics having moieties of penicillanic acid, cephalosporanic acid and ampicillin on both ends of the central polyalkylene were synthesized by reacting 6-aminopenicillanic acid (6-APAl), 7-amino cephalosporanic acid (7-ACA) and ampicillin with hexamethylene diisocyanate and sebacoyl chloride, respecetively. Antibiacterial activities of the compounds were also investigated.

• Bulletin of the Korean Chemical Society
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• v.31 no.10
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• pp.2918-2922
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• 2010

We demonstrate a facile route to synthesize silver chloride nanocubes and derivative nanomaterials. For the synthesis of silver chloride nanocubes, silver nitrate and hydrochloric acid were used as precursors in ethylene glycol, and poly (vinyl pyrrolidone) as a surfactant. Molar ratio of the two precursors greatly influenced the morphology and composition of the final products. As-synthesized silver chloride nanocubes showed size-dependent optical properties in the visible region of light, which is likely due to a small amount of silver clusters formed on the surface of silver chloride nanocubes. Moreover, we show for the first time that simple reduction of silver chloride nanocubes with different reducing reagents leads to the formation of delicate nanostructures such as cube-shaped silver-nanoparticle aggregates, and silver chloride nanocubes with truncated corners and with silver-nanograin decorated corners. Additionally, we quantitatively investigated for the first time the evolution of silver chloride nanocubes to silver chloride nanocubes decorated with silver nanoparticles upon exposure to e-beam. Our novel and facile synthesis of silver chloride related nanoparticles with delicately controlled morphologies could be an important basis for fabricating efficient photocatalysts and antibacterial materials.

• Journal of Soil and Groundwater Environment
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• v.8 no.3
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• pp.30-36
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• 2003

The effect of humic acid on the simultaneous removal of nitrate and phosphate was investigated in a micellar-enhanced ultrafiltration (MEUF). At the low molar ratio of cetylpyridinium chloride (CPC) to contaminants, the removal of nitrate was lower to 50％ by 100 ppm of humic acid due to the competition for binding on micelles. At the molar ratio higher than 3, however, the removal of nitrate was over 80％. Phosphate was removed over 80% at the molar ratio higher than 1. The CPC and humic acid were rejected over 99 ％ by UF membrane. The flux did not decrease by 100 ppm of humic acid but rather slightly increased since the humic acid adsorbed on the membrane made the membrane more hydrophilic. As a result, humic acid did not diminish the performance of MEUF in the simultaneous removal of nitrate and phosphate.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.51 no.6
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• pp.682-687
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• 2018

We investigated the effects of a highly saline solution (HS) containing hypochlorous acid, calcium chloride ($CaCl_2$), and phosphoric acid ($H_3PO_4$) on cell death and growth rate of laver Porphyra yezoensis and green laver Ulva intestinalis. Cell death rates of laver treated with HS and HS plus hypochlorous acid (HS + HOCl) in the harvesting stage were less than 0.5%, and there were no significant differences between the HS and HS + HOCl treatments. However, cell death of green laver treated with HS + HOCl in the harvesting stage was greater than 81.2%. These results indicate that the addition of HOCl is highly effective to eradicate noxious green laver without causing damage to laver. The addition of HOCl and $H_3PO_4$ to HS did not increase the area or weight of laver blades. A combination treatment of $CaCl_2$ and HS, however, significantly increased the area and weight of laver lades compared to controls (P<0.05).

• The Korean Journal of Physiology
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• v.24 no.1
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• pp.123-129
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• 1990

A comparative study of acid-base balance has been made between acidemia-induced hyperkalemia and hyperkalemia-induced acidemia. A group of rabbits was infused 0.1 N hydrochloric acid solution and metabolic acidosis was induced. Another group was administered 20 mM potassium chloride solution and hyperkalemia was induced. The third group was infused 0.1 N hydrochloric acid and 20 mM potassium chloride solution, simultaneously. Acid-base data and plasma potassium ion concentration were monitored every thirty minutes in these three groups of rabbits. Following results were obtained: 1 ) Along with the infusion of hydrochloric acid, acute metabolic acidosis was induced in the rabbits. Plasma bicarbonate ion concentration decreased primarily in this group. As a respiratory compensation, there was a tendency of reduction of arterial $Pco_{2}$. The alteration of data became larger along with the amount of administration and the time elapsed. However, hyperkalemia was not so severe compared with the second group. 2) In potassium chloride infused group, plasma potassium ion concentration increased along with the time elapsed and the amount of infusion. And the alteration of acid-base data was parrallel to the level of potassium ion concentration, above all depression of pH was prominent. 3) Above data suggest that when acute metabolic acidosis was induced, exchange of intracellular potassium ion with extracellular hydrogen ion seems significant for the regulation of extracellular acid-base balance. And when hyperkalemia was induced with the infusion of potassium chloride solution, the exchange of intracellular hydrogen ion with extracellular potassium ion also seems significant for the regulation of extracellular potassium balance. 4) In the group of rabbits infused hydrochloric acid and potassium simultaneously, disturbances of acid-base balance and potassium balance were much more severe than two other groups. In these mixed disturbances, the process of compensatory mechanism might be inhibited and one disturbance might aggregate each other. 5) Through above data it has been postulated that in acid-base disturbance potassium balance can be sacrificed as a compensatory mechanism, and vice versa in disturbance of potassium balance. And our data also suggest that hydrogen ion and potassium ion are compensatory pair, one another.