http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Reclamation of Acid Soil around S. Mine using Waste Materials as Neutralizing Agent
오승진(Seungjin Oh),이명호(Myeong-Ho Lee),오민아(Minah Oh),박찬오(Chan-Oh Park),정문호(Mun-Ho Jung),이재영(Jai-Young Lee) 한국지반신소재학회 2013 한국토목섬유학회 학술발표회 Vol.2013 No.11
The Soil pH is 5.8 ~ 6.2 in Korea because of many factors including the geological structure and climate condition. There is known as the cause for soil acidification by weathering of the mineral, excessive use of the chemical fertilizer, and extensively diffused acid rain. The purpose of research is the advanced neutralization using environmentally-friendly materials as waste resources against by acid soil. the physico-chemical property was analyzed to the acid soil and waste resource materials (waste lime, oyster shell, botton ash). The Batch-Test was performed under 3 stage. As a result, the experimental soil showed up about 3.19. Waste lime, oyster shell, bottom ash showed the alkalinity with 9.62, 10.08, 9.17 respectively. In case of the 1<SUP>st</SUP> Batch-Test experimental result, waste lime and oyster shell, the alkalinity was over 7.5 as good efficiency. On the other hands, the bottom ash showed the pH 4 of the neutralization efficiency which is low. Waste resource materials to be applied to the 2<SUP>nd</SUP> step were chosen as the waste lime and oyster shell except the bottom ash. In the 2<SUP>nd</SUP> Batch-Test, it was exposed to be the most appropriate in case of doing the combination ratio of the waste lime and oyster shell wit 9 : 1. As the economical and effectine aspect, combination ratio of the soil and materials was 9.6 : 0.6 with the 3<SUP>rd</SUP> step Batch-Test experimental result.
Soil Contamination Survey of Waste Landfill in the Past: ‘D’ District in Gyeonggi-do Province
( Seungjin Oh ),( Minah Oh ),( Jongbin Kim ),( Hyunho Jun ),( Hyungwook Kim ),( Youngjin Lee ),( Yoonsoo Park ),( Jai-young Lee ) 한국폐기물자원순환학회(구 한국폐기물학회) 2016 한국폐기물자원순환학회 춘계학술발표논문집 Vol.2016 No.-
Korea has been continuously extended to surrounding metropolitian area including Seoul city, because of the population growth and densitification of urban space. Several cases that the site of landfill area in the past has replaced and developed the housing site. There is serious contamination in soil and water system around landfill area since waste dumping had been prolonged unsanitarity. The ‘D’ district has been used waste landfill areas in the past. In addition, new town construction for residence is planned for the future. Therefore, the survey was carried out to determine the probability of soil contamination. Soil contamination survey was performed sampling and analysis according to Korea standard method for soil. Analysis parameters were selected as TPH(Total Petroleum Hydrocarbon), Zinc, Fluorine, Copper, Mercury, Arsenic on the basis of result from proceeded overall survey of the site. As a result fluorine contamination has emerged in most investigated points, and some points has TPH and arsenic contamination exceeded the standard measures. Mercury and copper were not detected. Almost of regional classification for land use are arranged by ‘2’ or ‘3’ areas. However, this district would be expected to change the regional classification as ‘1’ area which is for housing site. Therefore, the remediation and detailed investigation aimed at this district should be conducted.
Simulation of Nozzle Performances using the Free Energy Minimization Technique
Seungjin Oh,Yeongmin Kim,Iskandar Makhmudov,Sang-Hoon Lim 한국에너지기후변화학회 2009 에너지기후변화학회지 Vol.4 No.2
Nozzle performances for the frzen and equilibrium flows using H₂ and O₂ as reactants are simulated at their design conditions (third critical). the equilibrium compositions of constituent gases are determined by minimizing the free energy subject to mass balance constraints. Solutions of equilibrium constants are also provided to assess the accuracy of the technique.
Effect of Nb on hydride embrittlement of Zr–<i>x</i>Nb alloys
Oh, Seungjin,Jang, Changheui,Kim, Jun Hwan,Jeong, Yong Hwan Elsevier 2010 Materials science & engineering. properties, micro Vol.527 No.6
<P><B>Abstract</B></P><P>The effects of Nb on hydride Zr alloys were investigated. Various Zr alloys with different Nb content up to 2.0% were prepared in a sheet shape and charged with hydrogen up to 850ppm. It was found that the fraction of recrystallized grains was reduced with increasing Nb content during the heat treatment. Intergrain and intragrain hydrides were tangled in unalloyed Zr, which has fully recrystallized grains. On the other hand, Nb containing Zr alloys that have partially cold-worked grains had only intergrain hydrides precipitated along the rolling direction. In tensile tests, elongation was decreased significantly with increasing hydrogen content for unalloyed Zr. However, the reduction of elongation was less significant for Nb-containing alloys. The softening of the Zr matrix was caused by hydrogen, which was arrested in cold-worked grain. And β-Nb precipitates, which have high solubility of hydrogen, retarded the precipitation of hydrides, thereby enhancing the resistance of hydride embrittlement. Fracture surface of the tensile tested specimen was observed by SEM. From the SEM observation, secondary cracks caused by hydrides were found on the fracture surface of the hydrogen-charged specimens. Cleavage facets were observed on the fracture surface of unalloyed Zr; however, a mixture of dimple and cleavage facets was observed on the surface of the Nb-containing alloys, which indicates that Nb increased the resistance to hydride embrittlement of Zr alloys.</P>