• Air Cleaning Technology
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• v.4 no.3 s.15
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• pp.12-17
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• 1991

• Clean Technology
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• v.24 no.3
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• pp.175-182
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• 2018

In this research, we investigated the cleanliness by optimizing the water content of the aqueous stripper in fluidic strip process. The stripping properties of the photoresist with optimized aqueous stripper were compared with the commercial organic stripper. The stripping performance was evaluated by electrical and optical characteristics on the surface of the transparent electrode that compare with stripped the transparent electrode surface and the rare surface before patterning by the photoresist. As a result of the photoresist stripping process of the organic stripper and the aqueous stripper optimized for water content, the aqueous stripper exhibited better electrical and optical characteristics than the organic stripper. In the case of the fluidic strip process with organic stripper, the photoresist dissolves in the stripper solution during stripping which can cause re-adsorption by contamination. Whereas that the aqueous stripper under development seems to decrease the photoresist dissolution in the stripper solution. Because the cyclodextrin contained in the stripper captures organic photoresist into hall of cyclodextrin which stripped through swelling and tearing. The photoresist residue captured by the cyclodextrin can be filtered. After the fluidic stripping process by different chemical stripping mechanism, the cleanliness of the organic stripper and aqueous stripper was compared and analyzed.

• Clean Technology
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• v.13 no.4
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• pp.274-280
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• 2007

A liquid-liquid solvent extraction process was developed in this study to recover Fe and Ni from heavily concentrated aqueous ferric chloride solution, in an effort to substitute the conventional iron reduction method. Solvent composition and extraction conditions were first developed from the laboratory experiments, and the pilot system was designed and built for commercialization. Stage numbers for extraction and stripping were determined from pilot plant runs, and other operation data were obtained for mass production.

• Journal of the Korea Organic Resources Recycling Association
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• v.11 no.3
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• pp.51-59
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• 2003

In this study, the efficiency of M/F(micro filtration) system was investigated about the wastewater generated from the production process of ${\beta}-glucan$. M/F membrane used the pellicon 2 cassette filter module of millipore(USA) for the operation of M/F plant system. Flux was rised as operation pressure increased, and decreased with the operation time. As concentration ratio increased, the recovery of ${\beta}-glucan$, which was remaind in retentate was effective. As the fermentation solution of ${\beta}-glucan$ reused, the conversion ratio was 42.5%, and the status of fermentation was stable. Based on these results, we suggested that permeate was applicable as water reuse in cleaner production technology.

• Clean Technology
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• v.3 no.2
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• pp.28-30
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• 1997

발효 아미노산을 분리하는 기존의 공정인 이온교환법에서 폐액 및 폐수처리에 따른 문제점을 해결하기 위한 새로운 분리공정으로 탈염 전기투석과 Water-splitting Electrodiaysis를 이용한 발효 아미노산의 분리 가능성 및 다양한 cell configuration과 막에 대한 성능 실험을 실시하였다. 실험결과 전기투석에 의해 경도물질을 제거한 후 양이온교환막과 bipolar 막으로 구성된 2-compartment WSED로 효과적으로 발효액에서 아미노산을 분리 할 수 있었으나 1가 양이온에 선택성을 지닌 양이온교환막으로는 아미노산의 분리가 어려움을 알 수 있었다.

• Korean Journal of Food Science and Technology
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• v.25 no.2
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• pp.171-173
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• 1993

UV-ray air cleaner consisted of 6 watt UV lamp and fan was developed to sanitize air of refrigerator. Light intensity of the lamp showed 5 times of D value of Bacillus subtilis and air velocity around the lamp in holding section was 0.7 m/s, giving 0.33s of the resident time. The performance of air cleaner was tested with bacterial contaminator sprayed with suspension of Bacillus subtilis and hey powder. The device effectively decreased 80% of the population of airborn spore after 100 min operation at room temperature.

• Clean Technology
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• v.23 no.4
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• pp.401-407
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• 2017

This paper describes a shake-flask fermentation of Acacia flower producing whitening- and antioxidant- agents. Tyrosinase activity was inhibited in the presence of traditional and flask-fermentation broths whereas no inhibitory effect of flower extract was observed. Tyrosinase inhibition was 40% in the presence of solution containing 10% of extract from fermentation broth and it increased by increase in the concentration of it. Arbutin ($20mg\;mL^{-1}$) and kojic acid ($80{\mu}g\;mL^{-1}$) gave 90% and 58% inhibition, respectively. The result indicates that whitening activity of 40% extract solution was comparable to that of kojic acid ($80{\mu}g\;mL^{-1}$). The comparable antioxidant activity was observed for 60% extract and $10mg\;mL^{-1}$ vitamin solution. No noticeable toxicity was observed with extract. The physicochemical stability of fermentation supernatant was observed at room temperature storage condition. The result clearly shows that shake-flask fermentation of Acacia flower produced whitening agent for functional cosmetics.

• Clean Technology
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• v.29 no.2
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• pp.109-117
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• 2023

The purpose of this study is to develop a method for separating antioxidants and sugars from grape skin extract. The extract was first mixed with a variety of organic solvents to investigate whether the separation was feasible. When employing acetone, ethanol, dimethylsulfoxide, or dimethylformamide, the organic solvent-extract combination formed a single phase. However, when benzene, ethyl acetate, or n-hexane was added to the extract, the mixture separated into an organic and an aqueous phase and the pigments remained in the aqueous phase. On the other hand, when polyethylene glycol-2,000 (PEG-2000) and sodium citrate were added to the extract, the mixture was separated into three layers, with the majority of the flavonoids migrating to the top layer and 53% of the extract's glucose migrating to the bottom layer. The top layer had significant antioxidant activity, whereas the bottom layer showed no antioxidant activity. The glucose recovery in the bottom layer increased as the molecular weight of PEG increased and the highest recovery (67%) was observed when PEG-8,000 was added. The highest flavonoid separation was observed with PEG-2,000, followed by PEG-8,000 and PEG-400. The flavonoid separation when PEG-2,000 was added resulted in a flavonoid recovery of 48% and 0.2% from the top and bottom layers, respectively. Examining the effect of the separated solution using the agar disc diffusion method on yeast cell growth confirmed that the addition of the extract, the top, and the bottom layer did not inhibit cell growth.

• Clean Technology
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• v.15 no.3
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• pp.165-171
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• 2009

In this study, we found out the relation between $FeCl_3$ recovering-concentration and stage number of extraction process for invar (Fe+Ni) etching process. In order to get the desired $FeCl_3$ recovering-concentration economically, we developed the simulation program for designing the optimal $FeCl_3$ extraction process. We got the key parameter for this simulation program through pilot scale experiments. The process simulation by the developed program could reduce the emission of waste etching solution as well as the treatment costs. In addition, the developed program could calculate the number of stage of the etchant recovering system and the process time to get the desired concentration of $FeCl_3$. This program was used to compute the optimal capacity of the etchant recovering system and applied to the optimization of the stage of the etchant recovering system in real IT industry.

• Clean Technology
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• v.7 no.3
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• pp.161-167
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• 2001

A model was proposed for the removal of poly-dispersed suspended solid by deep bed filtration and the collection efficiency was investigated by computer simulation. Deposited particles on the collector surface may act as additional collector and reduce the pore size of the collector. As a result, the capability of removing suspended particles of the filter bed was improved with the deposition. The filtration process of poly-dispersed suspension shows higher collection efficiency than that of mono-dispersed suspensions. Since the large particles deposited on the collector surface may contribute to the increase of contact between collectors and small particles, the improved overall collection efficiency was obtained.