• 한국안전학회지
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• 제33권1호
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• pp.41-46
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• 2018

Experiments were carried out the phenomenal observation on effect of corona treated hotmelt laminating film in process of manufacture by 2 kinds of rolling speed and electric power variatons. Surface treatment by corona which is exposure of film surface to electron of ion bombardment, rather than mere exposure to active species, like atomic oxygen or ozone, can enhance adhesion by removing contaminant, electret, roughening surface, and introducing reactive chemical group. Reactive neutrals, ions, electron and photons generated during the corona treatment interact simultaneously with polymers to alter surface chemical composition, wettability, and thus film adhesion. However, it is highly recommended that extensive chains scission is avoided because it can lead to side-effect by forming sticky matter, resulting in dropouts. This paper reviews principles of surface preparation of polypropylene substrate by corona discharging. In addition, the experimental section provides a description of parameter optimization on corona discharging treatment and its side-effect. Experimental results are discussed in terms of surface wetting as determined by contact angle and SEM measurements. When the rolling speed of the film decreased from 1.666 [m / sec] to 0.083 [m / sec], contact angle decreased from $80[^{\circ}]$ to $64[^{\circ}]$, and the wettability was greatly improved. As the supply power increased from 0.4 [kVA] to 2 [kVA] at the corona discharge surface treatment, the contact angle decreased from $77[^{\circ}]$ to $65[^{\circ}]$, and the wettability was greatly improved.

• 한국막학회:학술대회논문집
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• 한국막학회 1997년도 심포지움시리즈 Jan-97 수처리용 분리막 기술 및 응용
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• pp.55-62
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• 1997

In Japan, the membrane filtration is becoming a common technology for municipal water supply system especially for small plant. 6 years before (1991), the national research project of membrane filtration for small plant has started. The project was named as "MAC 21", MEMBRANE AQUA CENTURY 21. In the project the Ministry of Health and Welfare, 8 universities and 18 water treatment plant companies have been involved. This was the first attempt to research a common theme in joint with government, universities and private companies. After three years, the guide line for membrane filtration application for small plant has been established. This has promoted to install some actual plant. And also, another joint research for "RESEARCH OF MEMBRANE FILTRATION FOR ADVANCED WATER TREATMENT" has started in 1994 and completed in March, 1997. The project was named as MAC21. In the former project the main objectives were removal of turbidity and bacteria from water. However, in new project the objective was establishment of the further advanced membrane filtration technology which would be applicable for trace chemical components removal such as tri-halo-methane pre-courser, agricultural chemicals removal, offensive smell and taste removal and virus removal. For the objectives, application of nanofiltration and hybrid-system, a combination of micro-filtration ultra-filtration with biological, ozone and activated carbon treatment process have been studied. In addition, application of membrane filtration for treatment of back-wash waste water originated from membrane filters and conventional sand filters has.been studied. At the end of March of this year, about 30 membrane filtration plants are actually supplying the water, the total treatment capacity is about 6,000 m$^{3}$/day and another 20 will be installed within one year.led within one year.

• 동굴
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• 제76호
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• pp.37-42
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• 2006

The Dielectric Barrier Discharge (DBD) is a nonequilibrium gas discharge that is generated in the space between two electrodes, which are separated by an insulating dielectric layer. The dielectric layer can be put on either of the two electrodes or be inserted in the space between two electrodes. If an AC or pulse high voltage is applied to the electrodes that is operated at applied frequency from 50Hz to several MHz and applied voltages from a few to a few tens of kilovolts rms, the breakdown can occur in working gas, resulting in large numbers of micro-discharges across the gap, the gas discharge is the so called DBD. Compared with most other means for nonequilibrium discharges, the main advantage of the DBD is that active species for chemical reaction can be produced at low temperature and atmospheric pressure without the vacuum set up, it also presents many unique physical and chemical process including light, heat, sound and electricity. This has led to a number of important applications such as ozone synthesizing, UV lamp house, CO2 lasers, et al. In recent years, due to its potential applications in plasma chemistry, semiconductor etching, pollution control, nanometer material and large area flat plasma display panels, DBD has received intensive attention from many researchers and is becoming a hot topic in the field of non-thermal plasma.

• 청정기술
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• 제21권1호
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• pp.33-38
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• 2015

본 연구에서는 전과정평가 방법론을 활용하여 액체 이산화탄소 제조 공정에 대한 전과정목록 DB를 구축하였다. 특성화와 정규화 결과, 액체 이산화탄소의 제조는 자원소모, 지구온난화 범주가 주로 영향을 미치며, 다음으로 산성화, 부영양화, 광화학적산화물생성 순이었다. 투입물의 기여도에서는 대부분의 영향범주에서 전력이 가장 높았으며 산성화와 부영양화에는 대기배출이 높은 기여도를 나타내었다. 오존층 파괴 범주의 경우 암모니아가 주된 원인이었다. 본 액체 이산화탄소 LCI DB를 통하여 탄소성적표지 등의 국가적 차원의 환경 전략 활용이 활성화되기를 기대한다.

• 자원리싸이클링
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• 제22권6호
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• pp.55-63
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• 2013

본 연구에서는 전기화학법으로 생성된 염소를 산화제로 이용하여 루테늄의 침출에 대한 연구를 수행하였다. 휘발성 루테늄산화물의 손실을 막기 위해 전 시스템이 밀폐형으로 제작된다. 루테늄의 침출의 최적조건을 조사하기 위해 pH, 온도, 전해 염소 생성시 인가전류 등의 영향을 조사하였다. 염소전해생성 시스템에 산화전류를 인가하여 염소가스를 발생시키고 침출조에 공급하여 루테늄 용해에 필요한 염소화합물을 생성시켰다. 산화제인 염소화합물의 농도가 포화상태에 도달하였을 때 루테늄 분말시료를 장입하고 침출반응을 진행하였다. 일정시간 간격으로 침출액을 채취하면서 루테늄 침출농도를 분석하였다. 본 실험결과 최적조건은 pH 10, 2 A, $40^{\circ}C$로 이 때 침출률은 88% 이다.

• 물과 미래
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• 제29권1호
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• pp.191-202
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• 1996

기존의 정수처리기법으로는 처리되지 않는 여러 가지 유기물질의 처리를 위해 상수고도처리가 도입되고 있다. 국내실정에 적합한 고도정수처리 시스템의 개발과 아울러, 이를 실생활에 도입할 경우의 소요비용과 사회적 영향에 대한 연구도 필요하다. 본 연구에서는 고도정수처리시스템의 설비비와 유지보수비를 산정하는 방법을 오존과 활성탄, 그리고 막분리 시스템을 중심으로 제시하고 이를 정부예산과 비교하여 타당성을 검증하였다. 또한 이를 바탕으로 투자비와 시설용랑에 관한 일반적인 관계식도 유도하였다. 한편, 정수된 상질의 물을 수요자에게 공급하는 방안을 네 가지로 검토하고 이를 부산지역에 적용하였다. 생산량과 수송체계에 따른 각각의 대안을 경제적/사회적 측면에서 비교한 결과, 음용수만을 고도정수처리하여 관로를 통하지 않고 병물로 공급하는 방안이 수질을 떨어뜨리지 않으면서 가장 경제성이 있는 방법인것으로 나타났다.

• Tribology and Lubricants
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• 제35권4호
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• pp.222-228
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• 2019

As rubber products such as O-rings, which are also known as packings or toric joints, come in regular, long term contact with liquid fuel, they can eventually swell, become mechanically weakened, and occasionally crack; this diminishes both their usefulness and intrinsic lifetime and could cause leaks during the steady-state flow condition of the fuel. In this study, we evaluate the lifetime of such products through compression set tests of FKM, a family of fluorocarbon elastomer materials defined by the ASTM international standard D141; these materials have great compression, sunlight, and ozone resistance as well as a low gas absorption rate. In this process, O-rings are immersed in the liquid fuel of airtight containers that can be expressed as a compression set, and the liquid fuel leakage in a flow rig tester at variable temperatures over 12 months is investigated. Using the Power Law model, our study determined a theoretical O-ring lifetime of 2,647 years, i.e. a semi-permanent lifespan, by confirming the absence of liquid fuel leakage around the O-ring assembled fittings. These results indicate that the FKM O-rings are significantly compatible for fuel tests to evaluate long-term sealing conditions.

• 청정기술
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• 제15권3호
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• pp.224-230
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• 2009

본 연구에서는 유리병 재사용에 대한 환경영향을 알아보기 위하여 전과정평가를 수행하였다. 연구범위로는 제품제조 및 원료수송 단계로 한정지었으며 360 mL 유리병 한 개를 기능단위로 사용하였다. 고려된 환경영향 범주는 6개로 자원고갈, 산성화, 부영양화, 지구온난화, 오존층파괴 및 광화학산화물 생성 등이었다. 전과정평과 결과, 자원고갈이 48.63%, 지구온난화가 46.27%로 두 범주가 가장 큰 환경영향을 보였으며 나머지 범주들은 상대적으로 미미한 영향을 보였다. 전체 공정 중 신병제조공정에 사용되는 화학약품에 의한 환경영향이 71.24%로서 주요인으로 나타났고 전력사용은 16.74%, 수송은 11.8%로 다음을 차지하고 있다. 또한 신병제조공정에 투입되는 화학약품 중 규산나트륨에 의한 환경영향이 45.68%를 차지하고 있어 자원고갈 및 지구온난화에 대한 기여도가 가장 큰 것으로 보인다.

• 한국재료학회지
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• 제33권11호
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• pp.475-481
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• 2023

Recently, the electron transport layer (ETL) has become one of the key components for high-performance perovskite solar cell (PSC). This study is motivated by the nonreproducible performance of ETL made of spin coated SnO₂ applied to a PSC. We made a comparative study between tin oxide deposited by atomic layer deposition (ALD) or spin coating to be used as an ETL in N-I-P PSC. 15 nm-thick Tin oxide thin films were deposited by ALD using tetrakisdimethylanmiotin (TDMASn) and using reactant ozone at 120 ℃. PSC using ALD SnO₂ as ETL showed a maximum efficiency of 18.97 %, and PSC using spin coated SnO₂ showed a maximum efficiency of 18.46 %. This is because the short circuit current (Jsc) of PSC using the ALD SnO₂ layer was 0.75 mA/cm² higher than that of the spin coated SnO₂. This result can be attributed to the fact that the electron transfer distance from the perovskite is constant due to the thickness uniformity of ALD SnO₂. Therefore ALD SnO₂ is a candidate as a ETL for use in PSC vacuum deposition.

• 한국포장학회지
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• 제29권3호
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• pp.223-228
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• 2023

Sustainable energy supplies without the recharging and replacement of the charge storage device have become increasingly important. Among various energy harvesters, the triboelectric nanogenerator (TENG) has attracted considerable attention due to its high instantaneous output power, broad selection of available materials, eco-friendly and inexpensive fabrication process, and various working modes customized for target applications. In this study, the amount of voltage and current generated was measured by applying the PSD profile random vibration test of the electronic vibration tester and ISTA 3A according to the time of Anodized Aluminum Oxide (AAO) pore widening of the manufactured TENG device Teflon and AAO. The discharge and charging tests of the integrated module during the random simulated transport environment and the recognition distance of RFID were measured while agricultural products (onion) were loaded into the returnable folding plastic box. As a result, it was found that AAO alumina etching processing time to maximize TENG performance was optimal at 31 min in terms of voltage and current generation, and the integrated module applied with the TENG module showed a charging effect even during the continuous use of RFID, so the voltage was kept constant without discharge. In addition, the RFID recognition distance of the integrated module was measured as a maximum of 1.4 m. Therefore, it was found that the surface condition of AAO, a TENG element, has a great influence on the power generation of the integrated module, and due to the characteristics of TENG, the power generation increases as the surface dries, so it is judged that the power generation can be increased if the surface drying treatment (ozone treatment, etc.) of AAO is applied in the future.