• Membrane Journal
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• v.30 no.5
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• pp.293-306
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• 2020

Increasing harmful effects of climate change, such as its effect on water scarcity, has led to a focus on developing effective water purification methods to obtain pure water. Additionally, rising levels of water pollution is increasing levels of environmental degradation, calling for sources of water treatment to remove contaminants. To purify water, osmotic processes across a semipermeable membrane can take place, and recent studies are showing that incorporating nanoparticles, including carbon quantum dots (CQDs), graphene carbon dots (GQDs), and graphene oxide quantum dots (GOQDs) are making thin film composite (TFC) membranes more effective by increasing water flux while maintaining similar levels of salt rejection, increasing the hydrophilicity of the membrane surface, showing bactericidal properties, exhibiting antifouling properties to prevent accumulation of bacteria or other microorganisms from reducing the effectiveness of the membrane, and more. In the review, the synthesis process, applications, functionality, properties, and the role of several types of quantum dots are discussed in the composite membrane for water purification.

• Fire Science and Engineering
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• v.28 no.6
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• pp.108-113
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• 2014

The combined process of Sliding Arc Plasma and corona dielectric barrier discharge process (CDBD) was used to efficiently improve harmful substance, which convert into OH radicals which have strong oxidation potential, and so have deodorization and sterilizing effects, by generating specific radicals and anion and then reacting with the moisture contained in harmful substance. As a result of experiment, even if the size of SAP reactor is reduced from 80 A to 50 A, there is no much change and therefore it is judged the size of reactor may be minimized. And it was confirmed that after the anion and ozone generated from CDBD rector react with harmful substance, a anion was reduced from 510,000 ppb to 470 ppb and ozone from 98 ppb to 22 ppb. It was also judged the stability and durability of plasma producer are excellent. Accordingly, it is considered the harmful substances which exist in indoor air quality will be efficiently improved and removed by using further plasma combined process through this study.

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2011.11a
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• pp.30-30
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• 2011

산업화 과정에 방출된 할로겐 화합물 및 프레온 가스가 오존층을 파괴하면서 많은 양의 자외선이 지표에 도달하여 생태계에 적지 않은 영향을 끼치고 있다. 자외선은 살균, 소독작용 및 Vitamin D 합성을 위해 생명체에 필수적이지만 과다할 경우 색소침착, 피부노화, 피부암 발생, 백내장의 증가, 면역기능저하 등의 피해를 준다. 자외선은 파장 영역에 따라 UV-A(장파장 자외선), UV-B(중파장 자외선)및 UV-C(단파장 자외선)으로 나뉜다. 이 중 인체에 가장 유해한 것으로 알려진 단파장의 UV-C는 파장이 짧아 침투력이 미약해 오존층과 성층권에서 대부분 흡수되므로 생물학적으로 큰 의미는 없다. 그러나 자외선 중 UV-B와 UV-A 영역의 자외선은 인체에 영향을 가장 많이 미치므로 이들 영역의 자외선을 차단하는 것이 필요하다. Vitamin C는 아스코르브산(ascorbic acid)이라고도 불리며 미백효과, 주름 개선, 자외선 차단 및 항산화 작용을 하지만 섬유가공 시 Vitamin C는 쉽게 산화되며 세탁 내구성이 떨어지기 때문에 가교제를 필요로 한다. Vitamin C를 이용하여 자외선 차단성 섬유제품을 개발하기 위해, 포름알데히드를 유리하지 않는 폴리카르복시산 가교제 중 하나인 Citric Acid(CA)를 사용하여 고온에서 면직물에 처리했을 때 에스테르 형 가교를 형성하여 내세탁성을 가질 수 있었다. 자외선 차단 효과를 알아보기 위하여 KS K 0850 섬유제품의 자외선 차단율 및 차단지수 시험방법으로 평가하였다.

• Proceedings of the Korea Water Resources Association Conference
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• 2012.05a
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• pp.712-712
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• 2012

하 폐수 처리방류수를 물리적, 화학적 그리고 생물학적 기술을 이용하여 처리한 후 재활용수로 이용하고자 하는 새로운 노력들이 진행되고 있지만 국내의 경우 방류수 재활용 기술과 처리수의 재이용에 대한 평가기술이 선진국에 비해 초기 단계에 있어 이 분야에 대한 적극적인 기술개발이 요구된다. 막 분리 기술을 이용한 처리 수는 소독 등의 추가적인 처리 없이 살수용수나 수경용수로 이용이 가능하며, 잔류염소를 유지시킬 경우 화장실 세정용수로의 이용도 가능하며, 또한 후처리 기술을 조합하면 고급 공업용수 등으로 사용가능하므로 선진기술로서 수요조건에 맞게 전 후 처리를 조합한 수요자 맞춤형 재이용수 공정기술을 개발할 필요가 있다. 이에 효율적인 하 폐수 재이용을 이용하여 농업용수(축산 음용수, 첨단 수출원예용수, 첨단 농업용수, 농산업 클러스터 복합 곡물 용수), 원예용수(원예단지), 공업용수 등의 다양한 용도에 활용 가능한 수요자 맞춤형 모듈 및 공정 개발을 수행하였다. 개발된 공정은 AOP 및 막 세정 시스템을 이용한 새로운 공정으로, AOP 시스템은 전기 이온 모듈을 통해 OH 라디칼을 생성 및 염분 제거 효율을 극대화 하여 오염 물질을 산화시키는 공정이며, FDA 시스템은 탁도가 높은 원수가 과다 유입 될 경우 후단 여과 막의 부하를 줄이는 역할을 하며, 부유 물질을 여과 시킨다. 막 세정 시스템은 미세 입자를 구성된 기포를 이용하여 눈에 보이지 않는 곳 까지 세척하며, 살균 작용을 하며, 분리 막의 성능을 증대 시킨다. 이어 UF 분리 막 시스템은 원수의 미세불순물, 박테리아, 스케일 물질 등을 제거하며, NF 시스템을 통하여 미립자, 박테리아 유기 화합물 및 2가 염 제거를 하여 재이용수를 생산하는 공정을 개발하였다. 개발된 수요자 맞춤형 공정은 하수 재이용 기술의 이용 목적 및 수요자별로 맞춤형으로 운영이 가능하며, 개발된 세척 기술은 분리 막 세정 유지관리비 및 에너지를 저감 할 수 있으며, 현장 적용의 실증화 과정을 거쳐 공정 기술을 신뢰도를 향상하고, 보유 기술을 수요자 맞춤형으로 업그레이드함으로써 기술의 경쟁력 및 고품질의 하수 재이용 기술의 새로운 방향을 제시 할 수 있을 것으로 판단된다.

• Journal of Food Hygiene and Safety
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• v.3 no.4
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• pp.211-215
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• 1988

Anion chromatographic (lC) method was developed for the determination of sulfites infoods. Sulfites refer to sulfur dioxide that was separated from a food sample by addition of acid and heating, and carried into a trapping solution by distillation. The trapping solution was applied to IC system. Sulfites was separated on an anionic separator column, HPIC-AS4A with 0.75mM $NAHCO_3/2.25mM\;Na_2CO_3$ as the eluent and determined by the use of conductivity detector. The recoveries of sulfites added to water, carrot and apple at level of 1 ppm were 99.8%, 91.6% and 83.5%, respectively. The detection limit was 0.2 ppm in the case of a 10 g sample size. All experiment could be finished within 20 minutes

• Korean Journal of Environmental Agriculture
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• v.19 no.4
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• pp.284-293
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• 2000

For the artificial removal of air pollutants such as pesticides, environmental toxicants, and pathogenic microorganisms in the greenhouse or the living environment, the accelerated photodegradation and the biocidal effects of some photosensitizers (PS)/photocatalysts (PC) were tested under the sunlight and/or artificial light. The selected photosensitizers/photocatalysts included the semiconductors (PC-1 and PC-2), the oxidizers (PC-3, PC-4, PC-5 and PC-6), the aromatic ketone (PS-7) and the aromatic amine (PS-8). In the case of dichlorvos, all the photocatalysts selected showed more accelerated photodegradation than the control without photocatalysts under both the sunlight and artificial light. Whereas, only the photocatalyst PC-1 accelerated the degradation of methyl tert-butyl ether about 17 times more than the control under both the sunlight and artificial light. Procymidone was much more degraded by the photosensitizer PS-8 and the two photocatalysts (PC-1, PC-6) than by PS-7. In the preliminary experiments to diminish the population of the microorganisms in the air, the photocatalyst PC-1 added to the suspensions of Pseudomonas putida, Phytophthora capsici, and Salmonella typhimurium obviously inhibited the microbial growth under the artificial light. The photocatalyst PC-1 showed a bactericidal activity against Salmonella typhimurium spread on the nutrient broth agar medium. These results suggest that the photosensitizers/photocatalysis under the light can remove some air pollutants and hence they can be used to reduce the exposure of the workers in the horticultural facilities and/or the public in the environment to the harmful pollutants.

• Analytical Science and Technology
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• v.25 no.6
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• pp.382-387
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• 2012

Ethylene oxide ($C_2H_4O$, EtO) is used as a raw material for the production of ethylene glycol and other industrially important material such as ethanolamines and also used as a disinfecting agent. It is applied for gas-phase sterilization of thermally sensitive medical equipment, and for processing of storage facilities as a mixture with fluorinated hydrocarbon. In this perspective, accurate determination of the mole fractions of components in the liquefied gas mixture is required for the quality control and safety of production and use. Each component of the liquefied gas mixture has different chemical and physical properties such as vapor pressure and boiling point. Therefore, we can suppose that analytical results can be different according to the introduction method for the gas phase of upper layer, or for the liquid phase of lower layer in gas cylinder. In this study, we designed a new on-line sample injection device for the liquefied gas mixture in liquid or gas state, and applied to the analysis of liquefied gas mixture of ethylene oxide and fluorinated hydrocarbons by GC/AED (gas chromatograph-atomic emission detector). We studied performance of AED, and effect of sample introduction and selected wavelength to the accuracy and repeatability of analytical results.

• Korean Journal of Food Science and Technology
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• v.47 no.4
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• pp.460-467
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• 2015

Sea urchin roe obtained from Anthocidaris crassispina and Pseudocentrotus depressus was briefly salt-fermented (5%), followed by ethanol treatment (1%) and the physicochemical properties as well as antioxidant activity were investigated. Compared to raw sea urchin roes, the salted one showed a significantly low amount of water (p<0.001) high salinity (p<0.05), ash content (p<0.001) and Na content (p<0.001). With salt-fermentation, the redness (p<0.05) and yellowness (p<0.001) of roe decreased noticeably, indicating the decomposition of endogenous carotenoids. Accordingly, the salted roe showed a lower DPPH radical scavenging activity than its unsalted counterpart. Additionally, it showed a significantly lower metal-chelating activity (p<0.05) and metal chelator content (e.g. ortho-phenolics) displayed by a negligible difference in titratable acidity. The salted roe showed significantly increased hardness (p<0.05) and total reducing capacity (p<0.001), which were attributed to the protein coagulation and the release of antioxidants bound to macromolecules after the ethanol treatment, respectively.

• Food Science and Preservation
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• v.9 no.2
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• pp.240-247
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• 2002

This study, to enhance the sterilization, browning inhibition and precooling effect of electrolyzed oxidizing water(EOW) as cleaning water on food industry, was carried out to investigate the efficacy of electrolyzed oxidizing water(EOW) with 0.85% NaCl, 0.5% ethanol, polysorbate 80 of 1 ppm, 0.5% lemon juice and 0.5% citron juice. Escherichia coli KCTC 1039 with initial count of 5.63$\times$10$\^$8/ CFU/mL were reduced to <10$^1$CFU/mL after 15∼30 sec when it was treated by electrolyzed oxidizing water added with various food additives. Bacillus cereus KCTC 1012 were reduced to <10$^1$ CFU/mL after 2 minutes treatment with electrolyzed oxidizing water containing polysorbate 80 and ethanol. Iactobacillus plantarum KCTC 3108 were reduced to <10$^1$CFU/mL after 30 sec treatment with electrolyzed oxidizing water containing polysorbate 80, citron juice and lemon juice, respectively. Erwinia carotovora subsp. carotovora KCTC 2776 were reduced to <10$^1$CFU/mL after 30 sec treatment with electrolyzed oxidizing water containing polysorbate 80 and lemon juice. Browning inhibition effect was determined by comparison of polyphenol oxidase activity. Inhibition ratio of polyphenol oxidase was approximately 62∼84% in most treatments with the exception of 57% and 25% inhibition by 0.5% ascorbic acid and polysorbate 80, respectively. Sliced potato dipped in electrolyzed oxidizing water containing NaCl and citron juice for 30 minutes showed significantly low PPO activity, 64 units in treatment with NaCl and 91 units in treatment with citron juice. At the same time, changes in color value(△E) of sliced potato was below 3 in most treatments.

• Clean Technology
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• v.18 no.4
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• pp.446-450
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• 2012

Strong alkaline electrolyzed water which is produced in cathode by electrolyzing the solution where electrolytes (NaCl, $K_2CO_3$ etc.) are added in diaphragm electrolytic cell, is eco-friendly and has cleaning effects. So, it is viewed as a substitution of chemical cleaner. In addition, strong alkaline electrolyzed water is being used by some Japanese automobile and precision parts manufacturing industries. When strong alkaline electrolyzed water is produced by using diaphragm electrolytic cell, it is necessarily produced at the anode side. Since strong acidic electrolyzed water produced is discarded when its utilization cannot be found, production efficiency of electrolyzed water is consequently decreased. Also, there is a weakness electrolytic efficiency is decreasing due to the pollution of diaphragm. In order to overcome this, non-diaphragm all-in-one electrolytic cell integrated with electrode reaction chamber and dilution chamber was applied. Strong alkaline electrolyzed water was produced for different composition of electrolytes, and their properties and characteristics were identified. In comparing the properties between strong alkaline electrolyzed water produced in diaphragm electrolytic cell and that produced in all-in-one electrolytic cell, the differences in ORP and chlorine concentration were found. In emulsification test to confirm surface-active capability, similar results were obtained and strong alkaline electrolyzed water produced in non-diaphragm all-in-one electrolytic cell was identified to be useable as a cleaner like strong alkaline electrolyzed water produced in diaphragm electrolytic cell. Strong alkaline electrolyzed water produced in non-diaphragm all-in-one electrolytic cell is thought to have sterilizing power because it has active chlorine which is different from strong alkaline electrolyzed water produced in diaphragm electrolytic cell.