냉간 가공용 인산염 피막처리의 저온화에 관한 연구

이만식(Man Sig Lee),정충택(Chung-Taeg Cheong),이광호(Gwang-Ho Lee),김준호(Jun-Ho kim),이근대(Gun-Dae Lee),홍성수(Seong-Soo Hong) 한국표면공학회 2002 한국표면공학회지 Vol.36 No.1

Zinc phosphating for cold forming of steel was studied with emphasis on decreasing phosphating temperature. To lower phosphating temperature, some techniques, such as adding Cu ion into bath, using activator in the form of pre-dip, and aeration in bath, instead of using conventional accelerator, namely oxidizing agent, have been tried. It was revealed that phosphating, leading to coatings of improved uniformity and fine crystal size, can be carried out using above techniques at lower temperature (55℃) compared to conventional phosphating temperature (80~90℃). Under present condition, it was seen that optimum concentrations of Cu ion in phosphating bath and activator in pre-dip are 0.015% (w/w) and 2.0 g/l, respectively. The coating weight was within the range of 15~20 g/㎡. When lubricant was applied into phosphating coatings, the amount of lubricating component (total soap) was found to be 6~10 g/㎡ and the lubricated panel revealed excellent lubricating properties.

가정을 위한 교회교육 ; 사회학적 입장에서 보는 가정의 문제점

이만식 ( Lee Man Sig ) 장로회신학대학교 기독교교육연구원 2004 교육교회 Vol.324 No.-

졸-겔법에 의한 나노크기의 티탄-콜로이드 합성 및 인산염 피막 특성

이만식(Man Sig Lee),이선도(Sun-Do Lee) 한국표면공학회 2005 한국표면공학회지 Vol.38 No.1

Nanosized titanium-colloid particles were prepared by sol-gel method. The physical properties, such as thermal stability, crystallite size and crystallinity according to synthesis condition have been investigated by TEM, XRD, SEM, TGA and DTA. In addition, Zinc phosphating has been studied in order to compare the phosphating characterization of prepared nanosized titanium-colloid particles. The major phase of all the prepared titanium-colloid particles was an amorphous structure regardless of synthesis temperature and the structure was composed of phoshate complex and titanium. The micrographs of HR-TEM showed that nanosized titanium-colloid particles possessed a spherical morphology with a narrow size distribution. The crystallite size of the titanium-colloid particles synthesized at 80℃ was 4-5 ㎚ and increased to 8-10 ㎚ with an increase of synthesis temperature (150℃). In addition, the coating weight increased with an increase of temperature of phosphating solution and when the concentration of titanium-colloid was 2.0 g/l, the coating weight was 1.0 g/㎡.

가스하이드레이트 구조 변형을 통한 메탄 저장에 관한 연구

이주동(Lee, Ju-Dong),이만식(Lee, Man-Sig),김영석(Kim, Young-Seok) 한국신재생에너지학회 2006 한국신재생에너지학회 학술대회논문집 Vol.2006 No.11

Structure H formation experiments were conducted in a semi-batch stirred vessel using methane as the small guest substance and neohexane(NH), tert-butylmethylether(TBME) and methylcyclohexane(MCH) as the large molecule guest substance (LMGS). The results indicate that the rates of gas uptake and induction times are generally dependent on the magnitude of the driving force. When tert-butyl methyl ether is used as the LMGS rapid hydrate formation, much smaller induct ion time and rapid decomposition can be achieved. Liquid-liquid equilibrium (LLE) data for the above LMGS with water have been measured under atmospheric pressure at 275.5, 283.15K, and 298.15K. It was found that TBME is the most water soluble followed by NM and MCH. The solubility of water in the non-aqueous liquid was found to increase in the following order: MCH<NH<TBME.

메탄-프로판 하이드레이트의 성장 특성에 관한 연구

이주동(Lee, Ju-Dong),이만식(Lee, Man-Sig),김영석(Kim, Young-Seok),송명호(Song, Myung-Ho) 한국신재생에너지학회 2006 한국신재생에너지학회 학술대회논문집 Vol.2006 No.06

Growth characteristics of methane-propane clathrate hydrate, growing under different undercooling conditions, was investigated. After the water within pressurized vessel was fully saturated with guest gas molecules by agitation, medium was rapidly undercooled and maintained at the constant temperature. The growth of hydrate was always Initiated with film formations at the upper bounding surface of liquid pool. The visual observation using microscope revealed detailed features of subsequent crystal nucleation, migration, growth and interference occurring within liquid pool. A number of small crystals ascended and settled at the hydrate film. When undercooling was small ({Delta}T=3.2K), some of the settled crystals slowly grew into faceted columns. As the undercooling increased, the downward growth of crystals underneath the hydrate film became dendritic and occurred with greater rate and with finer arm spacing. The shapes of the floating crystals were diverse and included octahedron and triangular or hexagonal platelet When the undercooling was small, the octahedral crystals were found dominant. As the undercooling increased, the shape of the floating crystals also became dendritic. The detailed characteristics of floating crystals were reported in this study.

울산지역 산업단지에서 배출되는 유기성슬러지의 물리·화학적 특성

이강우(Lee Gang-Woo),김민철(Kim, Min-Choul),이재정(Lee, Jae-Jeong),이만식(Lee, Man-Sig),김지원(Kim, Ji-Won),박흥석(Park, Hung-Suck),손병현(Shon Byung-Hyun) 한국산학기술학회 2008 한국산학기술학회논문지 Vol.9 No.6

본 연구는 울산지역의 산업단지에서 발생하는 유기성 슬러지에 대하여 삼성분, 원소조성, 발열량 및 열중량 분석을 실시하였다. 삼성분 분석 결과 평균값은 수분함량이 72.9%, 가연분이 18.5%, 불연분이 8.6%로 나타났으며, 원소분석 결과 평균값은 C 33.9, O 26.4, H 4.,, N 4.4, S 0.6%로 나타났다. 저위발열량이 1,500 ~ 2,000 kca1/㎏ 사이인 업체가 6개 업체, 2,000 kcal/㎏ 이상의 발열량을 가지는 4개 업체는 직접 연소 처리하여 에너지화하는 것이 가능할 것으로 판단된다. 산업분류 코드 업종별 시료에 대한 TGA 분석 결과,2개 업종에서 배출되는 유기성 슬러지의 경우 800℃ 이상에서 연소를 해야 할 것으로 판단되며, 3개 업종에서 발생하는 슬러지의 경우 600℃ 정도에서 저온 연소가 가능할 것으로 판단된다. In this study, we analyzed the physical and chemical properties such as proximate analysis, ultimate analysis, heating values, and thermogravimetric analysis for the organic sludges discharged from an industrial complex in Ulsan. The average water, combustible, and ash content of organic sludges were 72.9, 18.5, and 8.6%, respectively. And according to the ultimate analysis of organic sludges, the C, O, H, N, and S compositions were 33.9, 26.4, 4.4, 4.4, and 0.6%, respectively. According to the results of investigating the lower heating values, 6 sludges were on the range of 1,500 ~ 2,000 kcal/㎏ and 4 sludges were on the range of over 2,000 kcal/㎏. Therefore, these 10 sludges could be directly applied to industries which try to use the energy by direct incineration.

영남권(嶺南圈) 산업단지(産業團地) 발생폐기물(發生廢棄物)을 이용한 고형연료(固形燃料) 제조 특성에 관한 연구

강민수,김양도,류영복,이강우,이만식,Kang, Min-Su,Kim, Yang-Do,Ryu, Young-Bok,Lee, Gang-Woo,Lee, Man-Sig 한국자원리싸이클링학회 2009 資源 리싸이클링 Vol.18 No.6

RDF 생산 기술은 국내 실정에 맞는 제조 설비로 자체 생산할 수 있는 단계이지만, 사업장 가연성 폐기물에 대한 연료화 설비가 구축된 사례는 드물다. 본 연구에서는 사업장 가연성 폐기물을 대상으로 한 RPF(Refuse Plastic Fuel) 제조 공정의 고형연료 제조 가능성에 대해 검토하였다. 고형연료는 폐합성수지, 폐지 및 폐목재의 지역별 폐기물 발생비율 기준으로 제조되었으며, 제조된 RPF의 물리적 특성을 조사하였다. 대경(대구, 경북)지역을 기준으로 제조된 RPF의 발열량이 가장 높게 나타났으며, 폐지와 폐목재의 첨가량이 늘어날수록 발열량은 감소하였다. The level manufacturing technique for refuse derived fuel (RDF) is possible to produce them itself by a domestic process which is appropriate in Korea. However, very few facilities were used for industrial combustible waste. The objective of this research is to develop the technique for refuse plastic fuel (RPF) of industrial waste. RPFs were prepared by mixing of plastic, paper and wood based on amount of regional waste. The physical properties of the RPFs prepared were investigated. RPFs prepared at mixing ratio(plastic : paper : wood) of 87.55% : 8.15% : 4.3% show the highest lower heating values in wet-base (LHVW) and the LHVW decreases as the mixing ratio of paper and wood increases.

Si와 알칼리 금속의 첨가에 따른 물유리의 점도 및 분자결합구조 특성변화

류영복 ( Young Bok Ryu ),이만식 ( Man Sig Lee ) 한국공업화학회 2018 공업화학 Vol.29 No.1

주조공정 중 주형제조 시 점결제로 사용되는 silicate계 바인더의 주요원료 중 하나인 물유리와 첨가제(Si, 알칼리 금속)의 혼합특성을 살펴보았다. 물유리와 첨가제 그리고 비율에 따라 제조된 혼합물은 FT-IR분석을 통해 분자결합구조를 살펴보았으며, 점도측정으로 분자구조와의 상관관계를 비교하였다. 물유리에 Si 소스의 제공은 물질 내 Si 망상결합을 촉진시켜 점도는 증가하였고, 알칼리 금속을 첨가하였을 경우에 물유리의 Si 망상결합을 억제하여 점도가 낮아졌다. 물유리와 리튬 실리케이트(lithium silicate, LS)의 혼합물의 점도는 LS의 함량이 20 wt% 이하에서는 LS의 함량이 증가할수록 증가하였지만, 20 wt%를 초과할 경우 점차 낮아졌다. 물유리에 KOH를 첨가함으로써 점도를 낮출 수 있었으며, 콜로이달 실리카(colloidal silica, CS) 또는 potassium methyl siliconate (PMS)와의 혼합을 효과적으로 이용하는 데 이용할 수 있다. In this study, the mixing characteristics of water glass and additives (Si, alkali metal), which are one of the main raw materials of silicate based binder used in the production of molds during casting process, were examined. Molecular structures of water glass, additives and mixtures were analyzed FT-IR and viscosity measurements and their correlation were compared. The addition of Si source to the water glass accelerated the Si networking in the material and increased the viscosity. When the alkali metal was added, the viscosity of the water glass decreased by suppressing the Si networking of the water glass. Viscosities of the water glass and lithium silicate (LS) mixtures increased when the content of LS was less than 20 wt% and gradually decreased when the content was more than 20 wt%. By adding KOH to the water glass, the viscosity could be lowered and it could be used effectively to mix with colloidal silica (CS) or potassium methyl siliconate (PMS).

MoO3-SnO2-CeO2 촉매에 의한 대두유로부터 바이오디젤의 합성

정원영 ( Won Young Jung ),이만식 ( Man Sig Lee ),홍성수 ( Seong Soo Hong ) 한국화학공학회 2012 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.50 No.4

The production of biodiesel by transesterification of soybean oil was performed on MoO3, SnO2 and CeO2 mixed oxides. The catalysts were characterized using XRD and NH3-TPD. MoO3 showed the highest activity among the three metal oxides. When 7 wt% of catalysts was introduced into the reactants, the highest activity was obtained and the water added to reactant decreased the catalytic activity. MoO3 and SnO2 mixed with 50:50 showed the highest activity and CeO2 added with 20% on the MoO3-SnO2 mixed oxide also showed the highest activity. The catalytic activity showed to have a good relationship with the amount of acid site of catalysts. When the waste soybean oil was used as a reactant, the conversion was decreased about 30%.

Zn/La/Mg 삼원계 금속 산화물 촉매를 이용한 글리시돌 합성

하지해(Ji Hae Ha),이만식(Man Sig Lee) 한국산학기술학회 2021 한국산학기술학회논문지 Vol.22 No.8

본 연구에서는 바이오디젤의 부산물인 글리세롤로부터 생성된 글리세롤 카보네이트의 고부가가치화를 위해 글리세롤 카보네이트의 탈카르복시화(Decarboxylation)를 통하여 글리시돌을 제조하였다. Zn, La, Mg의 삼원계 촉매를 함침법으로 제조하였고, 제조된 촉매를 이용하여 글리세롤카보네이트의 탈카르복시화 반응을 통해 글리시돌 합성을 진행하여 담지 금속 종류에 따른 촉매 특성분석과 활성의 상관관계에 대하여 연구하였다. 제조된 촉매는 X-ray diffraction (XRD), N₂ adsorption-desorption isotherm, Field emission-scanning electron microscopy (FE-SEM) 및 NH₃/CO₂-temperature programmed desorption (TPD)를 이용하여 물리 · 화학적 특성 분석을 진행했으며, 글리세롤 카보네이트의 전화율 및 생성된 글리시돌 수율을 확인하여 촉매 특성과의 관계를 확인하였다. Zn/La 이원계 촉매에 Mg이 담지된 경우 산 및 염기점의 비율이 1.85로 가장 높게 나타났고, 그에 따라 88.06%의 글리시돌수율로 가장 높은 촉매 활성을 나타내었다. 본 실험 결과를 통하여 글리시돌의 합성에서 촉매 표면의 산 및 염기점의 높은 비율이 중요하게 작용된다는 것을 알 수 있었다. In this study, glycidol was synthesized by the decarboxylation of glycerol carbonate to increase its sustainability caused by a glycerol surplus in bio-diesel production. The ternary mixed oxide catalysts were prepared using Zn, La, Mg using an excess impregnation method. The glycidol was synthesized by the decarboxylation of glycerol carbonate over the prepared catalysts. The physicochemical properties of the catalysts were analyzed by X-ray diffraction (XRD), N₂ adsorption-desorption isotherm, field emission-scanning electron microscopy (FE-SEM), and NH₃/CO₂-temperature programmed desorption (TPD), the properties were correlated with the conversion of glycerol carbonate and the glycidol yield. The Mg-doped Zn/La ternary catalyst showed the highest catalytic activity with an 88.06% glycidol yield. The acid/base site density ratio on this catalyst was 1.85, indicating that the acid site is more distributed than the base site. In conclusion, the acid site density was a more decisive factor in the decarboxylation of glycerol carbonate than the base site density.