• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2003년도 가을 학술발표회 논문집
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• pp.513-518
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• 2003

Recently, advanced systems for water treatment are introduced for water quality improvement. One of those systems is water treatment method using ozone($O_3$). For it has strong oxidizing energy, it is necessary to have materisl stability against $O_3$. In this paper, epoxy resin specimens using as anticorrosive material of concrete structure for drink water are used to serve as a material of deterioration evaluation. It is to be studied weight loss, surface corrosion of specimens, ingredient analysis of floating particle, a solute of chemical ingredient by way of accelerated ozone testing. As the results of experiment, specimen weight is decreased. The surface of specimen is eroded heavily and showed a loss of gloss and floating particle, and in the stability for drinking water, harmful ingredient is not detected in the water.

• 한국잡초학회지
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• 제4권2호
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• pp.115-124
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• 1984

Chlorsulfuron (chemical name : 2-Chloro-N-(4-methoxy-6-methyl-1,3,5-triazin-2-yl)-aminocarbonyl-benzenesulfonamide) is a herbicidally active ingredient which shows effect against susceptible weeds already at such low rates like 5-20g active ingredient per hectare. In the here reported trials metabolism in several sensitive cultivated plants and weeds have been analysed using ^{14}C-labelled active ingredient. The uptake of chlorsulfuron by leaves or the root system is good in all plants species, and translocation takes place either symplasmatically or apoplasmatically. Metabolism takes place in all investigated plant species by development of hydrophile suhstances in roots and shoots. Decomposition of chlorsulfuron in roots and shoots of tolerant species (Triticum aestivum and Hordeum vulgare) to polare substances takes place quantitatively faster and quicker than in susceptible species (Beta vulgaris and Matricaria chamomilla).

• Journal of Microbiology and Biotechnology
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• 제12권6호
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• pp.993-997
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• 2002

A glucanhydrolase (a DXAMase exhibiting both dextranolytic and amylolytic activities) from Lipomyces starkeyi KSM 22 hydrolyzed polysaccharides having ${\alpha}-(1{\rightarrow}3)-,\;{\alpha}(1{\rightarrow}4)-,\;and\;{\alpha}-(1{\rightarrow}6)$-D-glucosidic linkages. The oral hygiene benefits of DXAMase-containing mouthwash were examined in relation to human experimental gingivitis during a 3-week period without brushing. The DXAMase-treated group exhibited a lower increase in plaque accumulation and gingival index score than the chlorhexidine-treated group. The DXAMase-treated group also showed less tongue accumulation, bad taste, and tooth staining, thus indicating a positive role for DXAMase as an antiplaque agent ingredient.

• 디지털융복합연구
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• 제15권10호
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• pp.571-577
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• 2017

본 연구에서는 식품으로 널리 애용되고 있는 막걸리의 항산화효능 및 티로시나아제 활성 억제효과를 연구하여 기능성 화장품 소재로서의 가능성을 평가하고자 하였다. 시료는 시판 막걸리 잔사에 MeOH 3 L를 가한 후 얻어진 현탁액을 농축한 후 EtOAc 3 L을 가하고 분획하여 상층을 최종시료로 사용하였다. MTT assay 평가에서는 $100{\sim}1,000{\mu}g/mL$ 범위의 농도에서 세포독성이 전혀 나타나지 않았고, 항산화활성은 농도 의존적 경향을 보였으며, EC50은 7.008 mg/mL로 높은 활성을 보였다. 또 티로시나아제 저해 활성 결과 추출물의 IC50 값은 49.22 mg/mL로 나타났다. 이상의 결과로 본 시료는 기능성화장품 원료로서의 가능성이 있음을 확인하였다.

• 한국안전학회지
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• 제36권3호
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• pp.24-30
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• 2021

Heat is generated during the synthesis and mixing process of chemical compounds due to a change in activation energy during the reaction. A runaway reaction occurs when sufficient heat is not removed during the heat control process within a reactor, rapidly increasing the temperature, reaction speed, and rate of heat generation inside the reactor. A risk assessment was executed using an RC-1 (Reaction Calorimeter) during Friedel-Crafts acylation. Friedel-Crafts acylation runs the risk of rapid heat generation during Active Pharmaceutical Ingredient (API) manufacturing; it was used to confirm the risk of a runaway reaction at each synthesis stage and during the mixing process. This study used experimental data to develop a safety efficiency improvement plan to control the risks of runaway and other exothermic reactions, which was implemented at the production site of a chemical plant.

• Animal Bioscience
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• 제36권6호
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• pp.908-919
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• 2023

Objective: Information about the chemical composition of cassava-based feed ingredients is needed to accurately formulate animal diets. A study was conducted to determine the chemical composition of cassava-based feed ingredients and to test the hypothesis that there is variation in chemical composition among cassava products originating from different South-East Asian countries. Methods: Sources of dried peeled and unpeeled cassava roots, cassava chips, cassava meal, high-ash cassava meal, and cassava residue were used. All samples were analyzed for dry matter, gross energy, nitrogen, amino acids (AA), acid-hydrolyzed ether extract (AEE), ash, minerals, total starch, insoluble dietary fiber, and soluble dietary fiber. Samples of peeled and unpeeled cassava roots, cassava chips, and cassava meal were also analyzed for sugars. Results: High-ash cassava meal had greater (p<0.05) dry matter and ash, but lower (p<0.05) total starch and gross energy than all other cassava products. Peeled cassava roots, unpeeled cassava roots, and cassava chips had greater (p<0.05) total starch than the other cassava-based ingredients. Cassava residue had greater (p<0.05) concentrations of lysine, insoluble dietary fiber, and soluble dietary fiber compared with the other cassava products, but tryptophan and glutamic acid were greater (p<0.05) in peeled cassava roots, cassava chips, and cassava meal samples compared with the other ingredients. Concentration of most minerals was greater (p<0.05) in high-ash cassava meal than in the other cassava products. Conclusion: Cassava-based ingredients sold as peeled roots, unpeeled roots, chips, or meal have chemical compositions that are not different from each other, and peeling has little impact on chemical composition. High-ash cassava meal has lower nutritional quality compared with other cassava products due to low starch and gross energy. The high fiber content in cassava residue makes this ingredient more suitable for ruminants and sows than for younger pigs or poultry.

• 한국가스학회지
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• 제22권4호
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• pp.49-54
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• 2018

원료의약품 제조회사에서는 화학반응에 의해 제품이 생산되기 때문에 화학반응 전 단계인 원료 분말을 투입하는 과정에서 화재 폭발사고가 자주 발생하고 있다. 이에 대한 실질적인 화학반응 단계에서 사고원인 분석을 통한 안전대책 연구는 많지 않다. 본 연구에서는 화학반응 단계에서의 위험성을 알아보고자 붕소제거 반응공정에서 발열에 대한 실험을 진행했다. 연구대상 반응공정은 실제 원료의약품 공장에서 합성하고 있는 제품을 대상으로 반응열량계를 이용하여 열적 거동을 조사하였다. 실제 제조현장의 반응공정에서 냉각실패 등의 이유로 발열할 수 있는 합성반응의 최대온도와 기술적 근거에 의한 최대온도를 비교해서 위험도를 예측하였다. 이러한 결과를 가지고 실제 제조현장에 적용하여 발열에 따른 폭주반응 위험성을 제어하는 안전대책을 제시하였다.

• 대한화학회지
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• 제59권4호
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• pp.349-352
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• 2015

• 한국자원식물학회지
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• 제26권3호
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• pp.403-409
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• 2013

This study has assessed the anti-oxidative activities and cytotoxic effects of Lithospermum erythrorhizon ethanol extract and measured the effects of tyrosinase inhibition activities with a goal of estimating the usage of the medicinal plant as an ingredient of cosmetics. First, to perform a basic test on the extract, pH and UV-spectrum were measured. According to the measurement, the extract had control functions at pH 5.5, and maximum absorbance occurred at 530nm. In particular, DPPH (1-1-diphenyl-2-picryl-hydrazyl)-inhibiting activity (IC50) and polyphenol content were 149.81 ${\mu}g/mL$ and $51.28{\pm}2.52$ mg/mL respectively. In addition, as extract concentration increased, tyrosinase inhibition activities improved as well. In raw 264.7 cell-based MTT assay, cell survival rates were 98% at 1000 ppm and 153% at 100 ppm. Therefore, it's been confirmed that there is almost no cytotoxin. According to the test results above, it appears that the Lithospermum erythrorhizon ethanol extract would be effective in anti-oxidation and application as a cosmetic ingredient.

• Biotechnology and Bioprocess Engineering:BBE
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• 제10권3호
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• pp.236-241
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• 2005

A decolorization process using ion exchange chromatography was developed to refine rhEGF as a cosmetic ingredient. A macroreticular resin (D314) was selected, with respect to its high decolorization rate and recovery yield of rhEGF, and the operational conditions of the decolorization process optimized. The optimum conditions were as follows: the rhEGF effluent was ion exchanged at a flow rate of 60.0mL/h, with an effluent pH 5.0, using a chromatographic column (i.d. 16mm) packed with D314, with a 7.5cm in bed height. The decolorization process was carried out under the optimum conditions, and halted when the effluent volume reached 350mL, giving a decolorization rate and recovery yield of rhEGF higher than 67 and $80\%$, respectively. When the decolorization rate exceeded $67\%$, the final product turned out to be white or light yellowish, which was to the satisfaction of the cosmetic standard.