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전유택(Yootaek JEON),박승환(Seunghwan PARK),박병철(Byungcheol PARK),강성균(Sunggyun KANG) 대한기계학회 2017 대한기계학회 춘추학술대회 Vol.2017 No.11
As interest in sustainable and eco-friendly energy increases, demand for hydrogen energy is also increasing. Hydrogenogenic CO oxidation (CO + H₂O → CO₂ + H₂) has the potential for H₂ production as a clean renewable fuel. In this study, it was developed economic biological hydrogen technology utilizing renewable resources such as industrial by-product gas including carbon monoxide, using the Thermococcus Onnurineus NA1. Pilot plant was designed and constructed in order to convert from CO in LDG which is a by-product gas of steel mill to H₂ and implemented the technology through demonstration. 2.4 Nm³/h of LDG was continuously supplied to 1t culture medium reaction tank. As a result, 97% CO gas in LDG was converted into hydrogen gas and hydrogen content in the product gas is 40% or more. The purity of product gas was increased to 99.9% hydrogen gas by PSA. The high purity hydrogen gas was successively used to generate electricity by fuel cell system which has developed in Hyundai Steel. This results is the first demonstration of H₂ production from steel mill by-product gas by a carboxydotrophic hydrogenogenic microbe.
Self-Assembly Characteristics of a Crystalline–Amorphous Diblock Copolymer in Nanoscale Thin Films
Kim, Young Yong,Ahn, Byungcheol,Sa, Seokpil,Jeon, Manseong,Roth, Stephan V.,Kim, Sang Youl,Ree, Moonhor American Chemical Society 2013 Macromolecules Vol.46 No.20
<P>A diblock copolymer of crystalline polyethylene (PE) and amorphous poly(methyl methacrylate) (PMMA), PE<SUB>69</SUB>-<I>b</I>-PMMA<SUB>92</SUB>, was synthesized; this polymer is thermally stable up to 270 °C. The morphological structures of thermally annealed nanoscale thin films of the copolymer were investigated in detail at various temperatures by using in-situ grazing incidence X-ray scattering (GIXS) with a synchrotron radiation source. Quantitative GIXS analysis found that the PE and PMMA blocks undergo phase separation to produce a vertically oriented hexagonal PE cylinder structure in the PMMA matrix that is very stable up to around 100 °C (which is the onset temperature of PE crystal melting and PMMA glass transition); over the range 100–200 °C, slight variations with temperature in the cylinders’ dimensions and orientation were observed. Furthermore, the PE block chains of the cylinder phase crystallize and undergo crystal growth along the cylinders’ long axes; however, these lamellar crystals do not stack properly because of the limited space along the cylinders’ short axes. As a result, the overall crystallinity is very low. The crystallization of the PE block chains in the diblock copolymer thin film is severely restricted in the diblock architecture by the confinement effects of the limited cylinder space and the anchoring of one end of the PE chain to the cylindrical wall interface. Surprisingly, however, in a nanoscale thin film the PE homopolymer forms a highly ordered lamellar structure; the lamellae are well stacked along the out-of-plane of the film, even though the crystallization is confined by the air and substrate interfaces. This well-ordered and oriented lamellar structural morphology does not arise in melt-crystallized PE bulk specimens.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/mamobx/2013/mamobx.2013.46.issue-20/ma401440y/production/images/medium/ma-2013-01440y_0008.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/ma401440y'>ACS Electronic Supporting Info</A></P>
Finite element analysis for temperature distributions in a cold forging
Dongbum Kim,Sungwook Kim,Inchul Song,이인환,조해용,Byungcheol Jeon 대한기계학회 2013 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.27 No.10
In this research, the finite element method is utilized to predict the temperature distributions in a cold-forging process for a cambolt. The cambolt is mainly used as a part of a suspension system of a vehicle. The cambolt has an off-centered lobe that manipulates the vertical position of the knuckle and wheel to a slight degree. The cambolt requires certain mechanical properties, such as strength and endurance limits. Moreover, temperature is also an important factor to realize mass production and improve efficiency. However, direct measurement of temperature in a forging process is infeasible with existing technology; therefore, there is a critical need for a new technique. Accordingly, in this study, a thermo-coupled finite element method is developed for predicting the temperature distribution. The rate of energy conversion to heat for the workpiece material is determined, and the temperature distribution is analyzed throughout the forging process for a cambolt. The temperatures associated with different punch speeds are also studied, as well as the relationships between load,temperature, and punch speed. Experimental verification of the technique is presented.
허광희 ( Heo Gwanghee ),이우상 ( Lee Woosang ),이규 ( Lee Giu ),서동환 ( Seo Dongwhan ),전준룡 ( Jeon Joonryong ),박병철 ( Park Byungcheol ) 한국구조물진단유지관리공학회 2004 한국구조물진단유지관리공학회 학술발표대회 논문집 Vol.8 No.2
This paper attempts to compute the coefficients of subgrade reaction from which the supporting capacity of piers can be estimated, using dynamic responses of energy applied to the vertical axis of piers in order to evaluate the safety of piers. To compute the coefficients of subgrade reaction, we built up a standard pier, using elastic springs already known which would represent a real condition of ground. We also induced a general relation expression between coefficients of subgrade reaction and eigen value, from numerical formula. After experiments regarding to dynamic responsive properties of a real standard pier, coefficients of subgrade reaction were computed by substituting dynamic properties for the general relation expression. Comparing those results and experimental data, we proved the usefulness of the general relation expression induced in this study.
허광희(Heo Gwanghee),이우상(Lee Woosang),이규(Lee Giu),서동환(Seo Dongwhan),전준룡(Jeon Joonryong),박병철(Park Byungcheol) 한국구조물진단유지관리학회 2004 한국구조물진단학회 학술발표회논문집 Vol.- No.-
This paper attempts to compute the coefficients of subgrade reaction from which the supporting capacity of piers can be estimated, using dynamic responses of energy applied to the vertical axis of piers In order to evaluate the safety of piers To compute the coefficients of subgrade reaction, we built up a standard pier, using elastic springs already known which would represent a real condition of ground We also induced a general relation expression between coefficients of subgrade reaction and eigen value, from numerical formula. After experiments regarding to dynamic responsive properties of a real standard pier, coefficients of subgrade reaction were computed by substituting dynamic properties for the general relation expression. Comparing those results and experimental data, we proved the usefulness of the general relation expression induced in this study