• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.5
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• pp.864-868
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• 2004

Iron is an essential ingredient for all metabolism in a living body However, because of the very low content of the iron in foods, many researches have been performed about iron-fortified food additives. We developed an iron-fortified food additive using the liposome that contain ferrous sulfate and hemin. For preventing the autoxidation of the ferrous sulfate, ascorbic acid was applied. Also, to prevent the oxidation of the liposome induced by the added ferrous sulfate and/or hemin, $\alpha$ -tocopherol was additionally applied. Though the effect of the added aqueous ascorbic acid did not show the antioxidative activity on the liposome containing ferrous sulfate and/or hemin, the added $\alpha$ -tocopherol in the phospholipid bilayer could retard the oxidation of the liposome. These results support that the liposome containing ferrous sulfate, hemin and ascorbic acid with the incorporated $\alpha$ -tocopherol could be applied in the food industry as an iron-fortified additive.

• Journal of the Korean Wood Science and Technology
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• v.49 no.1
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• pp.44-56
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• 2021

The carbonized length and area of plywood by the various spreading concentration of water glass and the type of additives were measured in accordance with the 45° MecKel's burner method of the fire protection performance standard of the Korean National Fire Agency. As a result of treating water glass with a concentration of 20 to 50 % on plywood, the flame retardancy tended to increase in proportion to the concentration of water glass. However, the optimum concentration of water glass was determined to be 30 % due to the efflorescence and sticky on the surface of plywood treated with high-concentration water glass of more than 30 %. As a result of the experiment by adding different proportions of additives to the water glass with concentration of 30 %, the standard of flame performance standard was satisfied under the conditions with the addition of 15% potassium hydroxide and 1-10% aluminum hydroxide, respectively. On the other hand, there were no significant difference in the flame retardancy by adding magnesium sulfate. These results about the flame retardancy of plywood by water glass and additives were expected to be basic data for improving flame-retardant treated wood.

• Journal of Korea Society of Waste Management
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• v.35 no.7
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• pp.640-646
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• 2018

Biomass-fired power plants produce electricity and heat by burning biomass in a boiler. However, one of the most serious problems faced by these plants is severe corrosion. In biomass boilers, corrosion comes from burnt fuels containing alkali, chlorine, and other corrosive substances, causing boiler tube failures, leakages, and shorter lifetimes. To mitigate the problem, various approaches implying the use of additives have been proposed; for example, ammonium sulfate is added to convert the alkali chlorides (mainly KCl) into the less corrosive alkali sulfates. Among these approaches, the high temperature corrosion prevention technology based on ammonium sulfate has few power plants being applied to domestic power plants. This study presents the results obtained during the co-combustion of wood chips and waste in a circulating fluidized bed boiler. The aim was to investigate the characteristics of pollution load in domestic biomass power plants with ammonium sulfate injection. By injecting the ammonium sulfate, the KCl content decreased from 68.9 to 5 ppm and the NOx were reduced by 18.5 ppm, but $SO_2$ and HCl were increased by 93.3 and 68 ppm, respectively.

• Food Engineering Progress
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• v.14 no.1
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• pp.65-74
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• 2010

Culture conditions of L. plantarum TJ-LP-002, the garlic resistant strain isolated from pakimchi (green onion kimchi), were investigated for the use of feed additives. Acetic acid, citric acid, lactic acid, and tartaric acid were detected in the culture supernatant, and especially the concentrations of lactic acid and acetic acid significantly increased during cultivation. The antimicrobial activity of L. plantarum TJ-LP-002 was not affected by proteases, calatase or cellulase, which showed that the antimicrobial activity might be due to the production of acids rather than proteinaceous antimicrobial substances. L. plantarum TJ-LP-002 was resistant to neomycin sulfate, spectinomycin dihydrochloride, and lincomycin hydrochloride, sensitive to streptomycin sulfate, and intermediate resistant to ampicillin trihydrate, chloramphenicol, erythromycin, tetracycline hydrochloride, and kanamycin sulfate. The optimum initial pH of medium, fermentation temperature and time for the cell growth and antibacterial activity were pH 7.0, 30${^{\circ}C}$ and 24hr, respectively. The optimal composition of culture medium for the cell growth and antimicrobial activity was 3%(w/v) glucose as a carbon source, 3%(w/v) yeast extract as a nitrogen source, and manganese sulfate and ammonium citrate as inorganic salts. The combinatorial supplementation of these inorganic salts, rather than sole addition as an inorganic salt, resulted in better antibacterial activity.

• Journal of the Korean Ceramic Society
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• v.11 no.1
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• pp.29-35
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• 1974

Effect of calcium sulfate and barium sulfate on the formation of portland cement clinker was studied by means of chemical analysis. DTA and X-ray diffraction analysis. In the presence of liquid phase, effect of the additives on the formation of tricalcium silicate was examined according to the reaction, 2CaO.$SiO_3$＋CaO$\longrightarrow$3CaO.$SiO_3$, which is the principal reaction in portland cement clinkerization, and optimum conditions in firing clinker concerning amount of additive, firing time and temperature were determined, and its kinetics was referred to. The experimental results are summerized as follow: (1) Appropriate burning temperature range of cement clinker is more limited as the content of calcium sulfate in clinker is increased. Amount of calcium sulfate, firing time and temperature in proper condition of clinkerization is related to each others. Being added suitable quantity of calcium sulfate, firing temperature of clinker can be lowered about $100^{\circ}C$. (2) When 3-5 mole% of calcium sulfate is added, firing time of 15-30 minutes at about $1380^{\circ}C$ is reasonable, and if the content is over7 mole %, firing for 1 hr. or more at $1350^{\circ}C$ is anticipated to be optimum condition. (3) In the reaction of tricalcium silicate formation, the role of barium sulfate as a mineralizer is similar to that of calcium sulfate, but the optimum firing temperature of cement clinker containing barium sulfate tends to be 20-$30^{\circ}C$ higher than that of clinker containing calcium sulfate. (4) When barium sulfate is used as mineralizer, 2-3 mole % of it to tricalcium silicate is recommended and if it is added more than this amount, free CaO is increased rapidly in clinker and alite formation is inhibited.

• Proceedings of the Korean Geotechical Society Conference
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• 2001.03a
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• pp.405-410
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• 2001

Bioremediation is a degradation process of existing organic contaminants in soils and groundwater by indigenous or inoculated microorganisms. This process can provide economical solution as well as safe and effective alternative in remediation technologies. However, it has been suggested that the rate of bioremediation process of organic contaminants by microorganisms can be limited by the concentration of nutrients and TEAs(Terminal Electron Accepters). In in-situ bioremediation, conventional pumping techniques have been used for supplying these additives. However, the injection of these additives is difficult in low permeable soils, and also hindered by preferential flow paths resulting from heterogeneities in high permeable ground. Therefore, the Injection of chemical additives is the most significant concern in in-situ bioremediation. Most recently, electrokinetic technique has been applied into the bioremediation and the injection characteristics under electrokinetics have not been examined in various soil types. Therefore, in this study, electrokinetic injection method is investigated in kaolinite and sand, and the concentration of ammonium(nutrients) and sulfate(TEAs) in soil is presented.

• Proceedings of the SAREK Conference
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• 2004.11a
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• pp.10-10
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• 2004

• Journal of the Microelectronics and Packaging Society
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• v.14 no.3
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• pp.37-42
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• 2007

Copper deposition studies have been actively studied since interests on 3D SiP were increased. The defects inside via can be easily formed due to the current density differences on entrance, bottom and wall of via. So far many different additives and current types were discussed and optimized to obtain void-free copper via filling. In this research acid cupric sulfate plating bath containing additives such as PEG, SPS, JGB, PEI and wave current applied electroplating were examined. The size and shape of grain were influenced by the types of organic additives. The cross section of specimen were analyzed by FESEM. When PEI was added, the denser copper deposits were obtained. Electroplaing time was reduced when 2 step via filling was employed.

• Korean Journal of Metals and Materials
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• v.48 no.8
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• pp.757-764
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• 2010

We report on the effect of additives on the microstructure and corrosion properties of electrodeposited Cu films. Copper films were fabricated by electrodeposition on various concentrations of gelatin in a copper sulfate electrolyte. The surface morphologies of the Cu films were observed using a scanning electron microscope (SEM), and crystal orientation of the Cu films was analyzed by X-ray diffraction measurement. (220) plane was the dominant orientation when the films were fabricated at ambient temperature, decreasing in dominance with addition of gelatin. On the other hand, (111) plane-Cu films were preferentially grown at $40^{\circ}C$, and were also diminished with adding additives. Corrosion rate measurements using the Tafel extrapolation method based on corrosion potential and current reveal the effect of additives on corrosion behavior. Corrosion behavior was found to be strongly related to the orientation of the films. Consequently, additives like gelatin influence crystal orientation of the films, and if a less dense crystal plane, e.g. (220), is preferentially oriented during electrodeposition, a lower corrosion rate could be produced, since the plane shows a lower current density.

• Korean Journal of Food Science and Technology
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• v.34 no.6
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• pp.998-1001
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• 2002

Micro-LC method for the quantitative determination of hydrogen peroxide in foods has been established. This method was carried out on cation-exchange resin gel column using distilled water as mobile phase with 50 mM sodium sulfate as electrolyte. The detection was performed with an electrochemical detector (ECD) at 0.6 voltage. Under this analytical condition, the recovery rates of hydrogen peroxide in tomato and lemon were 98.3 and 97.4%, respectively. Among 28 food types, hydrogen peroxide concentrations were 0.6, 0.5, 1.9, 0.9, 0.5, 0.6, 0.9, 0.8, and 0.4 ppm in banana, peach, orange, strawberry, pepper, onion, cucumber, burdock, and egg plant, respectively, Whereas none was detected in remaing 19 samples.