• Journal of the Korean Graphic Arts Communication Society
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• v.16 no.1
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• pp.25-38
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• 1998

The developing agent is the materials which first acts on silver grain and make it into metallic silver by reducing reaction. There are several types in developing agent, and according to Lumiere-Andresen principle, substitution product which has amino or hydroxyl group in benzen nucleus has a developing power, but all reduing substances are not in used. In the developing effect, not only the role of developing agent but also that of assistant materials are important. But in this work, we have studied effect, change by lith developing agent which require high contrast image. We made an developing experiment after having manufactured developing solution used hydroquinone and another developing agents like chlorohydroquinone, pyrocatechol and pyrogallol as developing agent. And we added that did in addition of diethanolamine and ascorbic acid, and then we examined the possibility of use.

• Microbiology and Biotechnology Letters
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• v.22 no.4
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• pp.347-352
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• 1994

Cytotoxic test was performed by SRB assay on human epidermoid carcinoma HEp-2 cell line for screening the soil microorganism, secreting anticancer agent. One microorganism was selected among two thousand microorganisms for its highest cytotoxicity. And this microorganism was identified with Streptomyces species after performing of diaminopimeric acid and reducing sugar analysis of cell wall and analysing the cultural characteristics and named Streptomyces sp. SM 1119. The effect of anticancer agent in SM 1119 culture extract on the cell cycle was studied by using GG$_{o}$ synchronized NIH 3T3 cells. The extract inhibited the serum stimulation of GG$_{o}$ NIH 3T3 cell only within 1 hour after serum stimulation but not after 6 hours. The extract also reduced the amount of c-myc mRNA in Colo 320 cell. These results suggest that the anticancer agent in the extract inhibits the progression of cell cycle very early stages, probably from G$_{0}$ to G$_{1}$.

• Fashion & Textile Research Journal
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• v.3 no.1
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• pp.42-47
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• 2001

The hardening system of polyurethanes has usually caused by air pollution. bad working condition and fire hazard according to using orgarnic solvents. Therefore there have been researched on emulsion, water soluble and colloid-dispersion based water soluble instead of using organic solvents recently. This study synthesized polyurethane dispersing particle by means of mixing precursor and neutralized emulsion method. In the first step, polyurethane was preparated from isophorone diisocyanate and poly (ethylene-adipate) glycol, and got precursor by introducing dimethyl propionic acid as a hydrophilic group. Synthesized polyurethane was bonded to the surface of fiber and crosslinked as a anti-static agent, and then looked for the change of color and softening property.

• Proceedings of the Korea Concrete Institute Conference
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• 2003.05a
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• pp.339-342
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• 2003

This study is intended to investigate the influence of chemical admixture on bleeding of concrete. According to the results, the amount of bleeding with elapse of time does not make much difference in the case of naphthalene type water reducing agent(RN), Naphthalene type high performance water reducing agent(HN) and Melamine type high performance water reducing agent(HM), but it is largest in the case of Polycarbonic acid type high performance water reducing agent(HP). Bleeding speed also is highest in the case of HP in comparison with other chemical admixture. This prove that high performance water reducing agent like HP has little effect on fluidity of concrete, but influences the amount of bleeding more greatly, instead. As properties of hardened concrete, compressive strength makes no difference in the case of RN, HN and HM, but on the other hand, it increases in the case of HP due to a decrease of air content and the large amount of bleeding.

• Culinary science and hospitality research
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• v.20 no.1
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• pp.178-188
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• 2014

Two kinds of anticaking agents (dextrin, polydextrose) were combined with kiwifruit paste at 5% w/w ratio and freeze-dried to prepare a powdered material. The physiochemical characteristics of kiwifruit powders with anticaking agents were compared with those without anticaking agents as the control. The yield was higher in the powders with anticaking agents than the control. Moisture content, acidity, and total phenolics were lower in the powders with anticaking agents than the control. The contents of vitamin C was higher in the powders with anticaking agents than the control, but was no significant difference with different anticaking agent types. There were no significant differences in free sugar content (fructose, glucose, total sugar) and organic acid content (oxalic acid, lactic acid, total) depending on the anticaking agent types. Hunter's L-value was significantly high in the order of the samples with dextrin, the control, and polydextrose, while a-value showed an opposite tendency. Browning index, water solubility, and swelling power didn't show any significant difference. However, the hygroscopicities with elapsed time were lower in the powders with anticaking agents than the control. Therefore, the kiwifruit powder combined with dextrin or polydextrose as an anticaking agent at 5% w/w ratio could be used as a food biomaterial with a good quality in moisture, vitamim C, color value, browning index, water solubility, and hygroscopicity.

• Journal of The Korean Society of Grassland and Forage Science
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• v.42 no.4
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• pp.229-236
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• 2022

This study was conducted to evaluate the efficacy of adding the microbial inoculants to silage for reducing mycotoxins in rice straw silage. When a single agent of L. plantarum and a mixed agent of L. plantarum and S. cerevisiae were added in rice straw silage contaminated mycotoxins, it had an effect on silage fermentation and fiber degradation as well as mycotoxin reduction. Among the mycotoxins, only ochratoxin A and zearalenone were found in the test sample. Ochratoxin A and zearalenone showed a decreasing trend with the addition of silage inoculants compared to the control groups (38.11±2.22 and 633.67±50.30 ㎍/kg), and there was a significant difference at the mixed agents; 27.78±2.28 and 392.72±25.04 ㎍/kg, respectively (p<0.05). The pH was lower in the single agent and the mixed agent compared to the control (p<0.05). The concentration of lactic acid was higher in the single agent (11.73±0.31 mM) than in the control group (8.18±0.93 mM), and the highest concentration was 16.01±0.88 mM in the mixed agent (p<0.05). Acetic acid and propionic acid were found to be significantly lowered with the addition of silage inoculants (p<0.05). Total VFA was also lower at the addition of silage inoculants than the control group (p<0.05). The rumen in situ dry matter degradation of NDF and ADF was maintained at the highest levels of the mixed agent during the culture period, followed by the single agent and the control group at the lowest level. NDF and ADF degradation showed a significant difference at all time points after 12 and 24 hours of culture, respectively (p<0.05). The study results showed that the silage inoculants had the positive effects on quality increasing of rice straw silage; fermentative charateristics, fiber degradation and mycotoxins reduction. Ochratoxin A and zearalenone were greater reduction by adding bacterial inoculants of silage. Therefore it is considered that L. plantarum and S. cerevisiae will improve the quality and stability with remediation of mycotoxin in silage.

• Journal of Microbiology and Biotechnology
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• v.26 no.1
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• pp.61-65
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• 2016

From the lees of bokbunja wine (LBW) made from Rubus coreanus Miquel, we have identified six compounds (1: trans-4-hydroxycinnamic acid; 2: trans-4-hydroxy-3-methoxycinnamic acid; 3: 3,4-dihydroxycinnamic acid; 4: 4-hydroxy-3-methoxybenzoic acid; 5: 3,5-dimethoxy-4-hydroxybenzoic acid; and 6: 3,5-dimethoxy-4-hydroxycinnamic acid (sinapic acid)) through silica gel chromatography and UHPLC-MS. The compounds 1-6 showed strong anticoagulation and platelet aggregation inhibitory activities without hemolytic effect against human red blood cells. To date, this is the first report of the in vitro anti-thrombosis activity of sinapic acid. Our results suggest that different cinnamic and benzoic acid derivatives are closely linked to the anti-thrombosis activity of LBW, and sinapic acid could be developed as a promising anti-thrombosis agent.

• Journal of the Korea Organic Resources Recycling Association
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• v.21 no.4
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• pp.82-87
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• 2013

A study on desorption and regeneration characteristics for silver ions adsorbed onto crab shells was carried out by means of Nitric acid soultion which was selected as the best desorbing agent. Desorption efficiency for silver ions was the highest as about 96% at the 1.0M of Nitric acid concentration. Also, silver ions was almost desorbed below 1.0 of S/L(mg/mL) ratio which is defined as the ratio of adding amount of adsorbent and volume of desorbing agent and most of desorption process was completed within 60min. And removal efficiency of reused crab shells for silver ions was maintained as about 92% until the 2nd cycle.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.47 no.2
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• pp.34-41
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• 2015

Recovered paper has been widely used as a main raw material of papermaking in Korea. Recycling of recovered paper helps to reduce production cost and preserve an environment. To recycle recovered paper efficiently, de-inking is a key process in recycling mills. De-inking process would be affected by various influencing factors such as the type of de-inking agent, mixed ratio of recovered paper, season, and process conditions. In this study, fatty acid and nonionic surfactant were used as the de-inking agent in froth-flotation process of mixed recovered paper. De-inking properties of mixed recovered paper were investigated according to the addition level of each chemical. Nonionic surfactant had a small effect on de-inking efficiency of mixed recovered paper due to decreased reject. As the additional level of fatty acid increases, fragmented ink particles increased and then optical properties of recycled paper decreased because fragmented ink particles adsorbed onto the fiber surface.

• Journal of the Korean Applied Science and Technology
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• v.21 no.4
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• pp.306-312
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• 2004

An acid cleaning agent (AACA) for aluminum was prepared by blending of sorbitol, n-octanoic acid, MJU-100A, Tetronix T-701, PPA-23, C8-83 and phosphoric acid. With the prepared AACA, degreasing, foam height, etching and derusting tests were carried out. As a result, AACA-4 and AACA-7 showed better cleaning ability than commercial acid cleaning agents.