• 한국지하수토양환경학회지:지하수토양환경
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• 제14권1호
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• pp.61-67
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• 2009

현장규모의 유류오염 토양세척에 따른 세척 유출수를 처리하기 위해 다단계 물리화학적 무방류 수처리시스템을 이용하였다. 오염토양세척 후 세척토양과 세척수 처리효율을 평가하기 위해 단위공정별 잔류하는 TPH(세척토양), COD$_{Mn}$, SS, n-hexane을 분석하였다. 세척 유출수 시료채취지점은 침사지,응집 침전조 그리고 유수분리조의 유출수,공정수,저장조 유입수로 4곳의 시료채취 지점에서 총 3회에 걸쳐서 실시하였다. 또한 약8개월간의 토양세척 및 공정수 저장조의COD$_{Mn}$, SS, 그리고 n-hexane을 분석하였다. 그결과, 오염토양의 농도조건과 상관없이 오염토양의 세척효율이 평균95.9%로 높았고, 수처리 공정 최종 방류구인 공정수 저장수의 COD$_{Mn}$, SS, 그리고 n-hexane가 수질환경보전법상 청정지역 방류수질기준 미민으로 검출되었다. 현장규모의 토양 세척수 처리시스템은 세척수를 100%세척공정수로 재이용하여 환경친화적이고 경제적인 토양세척 처리공법이 될 수 있음을 시사하고 있다.

• 동력기계공학회지
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• 제13권6호
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• pp.63-69
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• 2009

The experiment was performed to check operating characteristics of fouling auto removal apparatus for multi pass type heat exchanger using ejector. The results showed as following. The ejector suction flow rate increased with the head of operating pump of ejector. Proper suction flow rate showed $7.2{\sim}10.2m^3/h$ for ball collection in case of pump head 35~50m. The head of ejector outlet pipe is below 4.1m in case of 40m, the head of operating pump of ejector to confirm ejector suction flow rate 8.4m3/h. Lattice space of ball separator is allowed 6~10.3mm in ranges of ball diameter are 15~25mm and when mass flow of cooling water is 3.0m/sec. Average of passing time of balls is 1.2~2.8sec depend on the velocity of flow and the size of balls.

• 한국초전도ㆍ저온공학회논문지
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• 제6권3호
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• pp.27-32
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• 2004

High temperature superconducting coated conductor has a structure of /< superconducting layer>//. The buffer layer consists of multi layer, and the architecture most widely used in RABiTS approach is CeO$_2$(cap layer)/YSZ(diffusion barrier layer)/CeO$_2$(seed layer). Evaporation technique is used for the CeO$_2$ layer and DC reactive sputtering technique is used for the YSZ layer, A chamber was set up specially for DC reactive sputtering, Detailed features are as following. A separator divided the chamber into two halves a sputtering chamber and a reaction chamber. The argon gas for sputtering target elements flows out of the cap of sputtering gun, and water vapor for reaction with depositing species spouts near the substrate. Turbo pump is connected with reaction chamber. High speed deposition of YSZ film could be achieved in the chamber. Detailed deposition conditions (temperature and partial pressure of reaction gas) were investigated for the rapid growth of high quality YSZ film.

• 한국수산과학회지
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• 제18권2호
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• pp.139-148
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• 1985

잉어와 붕장어의 어체 전처리 방법에 따른 동결저장중의 어묵형성능에 관하여 실험한 결과는 다음과 같다. 어체 전처리방법으로써 전어체, 채육기로 채육한것, 채육하여 수세탈수한 것 및 고기풀의 4종 상태로 처리하여 $-30^{\circ}C$에서 3개월 동안 동결저장했을때 원료 및 제품의 품질은 모두 전체적으로 양호한 편이었다. 어체 전처리방법에 따라 처리하여 동결저장한 원료로써 만든 어묵제품 품질은 잉어의 경우, 전어체 그대로 동결저장하는 것이 제품 품질이 가장 양호하였고 그 다음이 채육기로 채육한 것, 채육하여 수세탈수한 것 및 고기풀의 순이었으며, 붕장어에서는 고기풀 상태로 저장한 것이 가장 좋았으며 다음이 전어체, 채육하여 수세탈수한 것, 채육기로 채육한 것의 순이었다.

• Nuclear Engineering and Technology
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• 제34권5호
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• pp.494-501
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• 2002

Radioactive Corrosion Products (CRUD) which are generated by the neutron activation of general corrosion products at the nuclear power plant are the major source of occupational radiation exposure. Most of the CRUD has a characteristic of showing strong ferrimagnetisms. Along with the new development and production of permanent magnet (rare earth magnet) which generates much stronger magnetic field than the conventional magnet, new type of magnetic filter that can separate CRUD efficiently and eventually reduce radiation exposure of personnel at nuclear power plant is suggested. This separator consists of inner and outer magnet assemblies, coolant channel and container surrounding the outer magnet assembly. The rotational motion of the inner and outer permanent magnet assemblies surrounding the coolant channel by driving motor system produces moving alternating magnetic fields in the coolant channel. The CRUD can be separated from the coolant by the moving alternating magnetic field. This study describes the results of preliminary experiment performed with the different flow rates of coolant and rotation velocities of magnet assemblies. This new magnetic filter shows better performance results of filtering the magnetite at coolant (water). How rates, rotating velocities of magnet assemblies and particle sizes turn out to be very important design parameters.

• 청정기술
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• 제19권4호
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• pp.379-387
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• 2013

본 총설에서는 최근 청정수소생산방법으로 큰 관심을 받고 있는 에탄올 수증기개질반응(ethanol steam reforming reaction)에 대해 소개하고자 한다. 다양한 촉매, 반응온도, 에탄올과 물의 몰비에 따른 에탄올 수증기개질반응의 반응특성 및 반응속도식(reaction rate equation)을 검토해 보고자 한다. 또한, 반응기와 분리기를 동시에 장착한 새로운 개념의 막반응기(membrane reactor)를 소개하며, 막반응기의 사용이 일반적인 충전층반응기(packed-bed reactor)에 비해 에탄올 전환율과 수소 수율에 어떠한 영향을 주는지에 대하여 고찰해 보고자 한다.

• Bulletin of the Korean Chemical Society
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• 제30권3호
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• pp.595-598
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• 2009

The authors describe an analytical method to determine total chlorine in a sanitizer liquid, incorporating a lab-made He-rf-plasma within a PDMS polymer microchip. Helium was used instead of Ar to produce a plasma to achieve efficient Cl excitation. A quartz tube 1 mm i.d. was embedded in the central channel of the polymer microchip to protect it from damage. Rotational temperature of the He-microchip plasma was in the range 1350-3600 K, as estimated from the spectrum of the OH radical. Chlorine was generated in a volatilization reaction vessel containing potassium permanganate in combination of sulfuric acid and then introduced into the polymer microchip plasma (PMP). Atomic emission lines of Cl at 438.2 nm and 837.7 nm were used for analysis; no emission was observed for Ar plasma. The achieved limit of detection was 0.81 ${\mu}g\;mL^{-1}$ (rf powers of 30-70 W), which was sensitive enough to analyze sanitizers that typically contained 100-200 ${\mu}g\;mL^{-1}$ of free chlorine in chlorinated water. This study demonstrates the usefulness of the devised PMP system in the food sciences and related industries.

• 한국입자에어로졸학회지
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• 제9권1호
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• pp.23-29
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• 2013

Inertial impaction type mist eliminators are the most effective instruments to separate mist from the gas. In this work, the effect of the horizontal chevron type mist eliminators is characterized experimentally. Droplet size distribution and evaluation of removal efficiency of the chevron type mist eliminators at different gas flows were investigated using an aerosol particle size analyzer and a portable aerosol spectrometer, respectively. The experimental investigations showed that the mist removal efficiency in these instruments is dependent in the droplet size, and the pressure drop is nil.

• 전기화학회지
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• 제12권4호
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• pp.324-328
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• 2009

양극 (cathodes)과 음극 (anodes)이 서로 물리적으로 닿게되는 내부 단락 (internal short-circuit) 현상은 리튬이차전지 안전성 (safety) 이슈의 주요 원인으로 고려되고 있으며, 분리막 (separators)의 열 안정성 (thermal stability)에 의해 크게 영향을 받는 것으로 알려져 있다. 본 연구에서는 기존 폴리올레핀 (polyolefin) 계열 분리막에 비해 열 안정성이 현저히 개선된 세라믹 복합막 구조의 신규 분리막을 개발하여, 전지 내부 단락 발생을 억제하고자 하였다. 본 연구의 복합분리막은 알루미나 ($Al_2O_3$) 나노입자와 PVdF-HFP (polyvinylidene fluoride-hexafluoropropylene) 바인더로 구성된 세라믹 코팅층을, 폴리에틸렌 (polyethylene, PE) 분리막 양면에 도입시킴으로써 제조되었다. 세라믹 코팅층의 모폴로지는 코팅용액의 상전이 (phase inversion) 현상 제어를 통해 결정되었으며, 비용매 (물) 함량이 증가함에 따라 기공크기 및 기공구조가 보다 더 발달되었다. 이러한 세라믹 코팅층의 기공구조 변화는 복합분리막의 열 안정성 및 전기화학특성에 큰 영향을끼치는 것으로 관찰되었으며, 이를 상전이 현상 관점에서 체계적으로 해석하였다.

• 한국물환경학회지
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• 제36권2호
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• pp.153-163
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• 2020

Magnetic separation technology is an efficient and environmentally friendly technology. Compared with the traditional wastewater treatment technology, the magnetic separation technology has its unique advantages and characteristics, and has been widely applied in the field of wastewater treatment. In particular, the emergence of superconducting magnetic separation technology makes possible for high application potential and value. In this paper, which through consulting with the literatures of Korea, Chinese, United States and other countries, the magnetic separation technology applied to wastewater treatment was mainly divided into direct application of magnetic field, flocculation, adsorption, catalysis and separation coupling technology. Advantages and limitations of the magnetic separation technology in sewage treatment and its future development were also studied. Currently, magnetic separation technology needs to be studied for additional improvement in processing mechanism, design optimization of magnetic carrier and magnetic separator, and overcoming engineering application lag. The selection, optimization and manufacturing of cheap magnetic beads, highly adsorbed and easily desorbed magnetic beads, specific magnetic beads, nanocomposite magnetic beads and the research of magnetic beads recovery technology will be hot application of the magnetic separation technology based on the magnetic carriers in wastewater treatment. In order to further reduce the investment and operation costs and to promote the application of engineering, it is necessary to strengthen the research and development of high field strength using inexpensive and energy-saving magnet materials, specifically through design and development of new high efficiency magnetic separators/filters, magnetic separators and superconducting magnetic separators.