• Journal of The Korean Association For Science Education
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• v.31 no.6
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• pp.942-957
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• 2011

The purpose of this research was to examine the concept of elementary school teachers of combustion. The participants were selected from the elementary school teachers who had various career experiences, 6th grade science teaching experiences, and academic backgrounds on science. For the purpose of this study, 12 elementary school teachers took the concept-test formed five questions on combustion and were interviewed. The concept-test was composed with 'The definition of combustion', 'The reason that the candle was blown out when glass was closed.', 'The existence of oxygen and carbon dioxide of before and after combustion in glass', 'Combustion of iron', 'Combustion products'. And the collected data by semi-structured interviews based on responses to the concept-test. During the analysis of the data, additional interviews by phone, e-mail and Internet messenger were conducted if necessary. The answers to each question were classified into three levels: (Scientific-concept(S), Partial-concept(P), Misconcept(M)). The research results showed that all teachers had misconceptions or partial-concept of more than 50 percent of each question. Teachers who had the 6th grade science teaching experience acquired scientific concepts of the combustion more than teachers who did not have the 6th grade science teaching experience. We should develop visualization materials about the change of gases during combustion and use these materials for implementation of the scientific concept.

• Fire Science and Engineering
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• v.15 no.3
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• pp.7-13
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• 2001

In this paper, we had analyzed comsbustion gases according to pyrolysis $600^{\circ}c$, $800^{\circ}c$ and $1000^{\circ}c$ for polymeric material using a GASTEC colorimetric gas detector tube in order to combustion gases toxicity evaluation for flame retardant untreated ply wood, flame retardant treated ply wood, flexible polyvinyl chloride and flexible polyurethane foam of polymeric material. As a result, comsbustion gases producted from small specimens of polymeric material had reached fatal to man at a 30 minute exposure time that had possesed toxicity index. Toxicity index at pyrolysis $800^{\circ}c$ of flexible polyvinyl chloride was 31.74. Flexible polyvinyl chloride was the highest toxicity index of flame retardant untreated ply wood, flame retardant treated ply wood, flexible polyvinyl chloride and flexible polyurethane foam. The comsbustion gases producted commonly no concern with pyrolysis temperature had analyzed carbon dioxide($CO_2$) and carbon monoxide(CO). Toxicity index had investigated differently according to pyrolysis temperature even a similar materal.

• Journal of the Korean Society of Marine Environment & Safety
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• v.7 no.1
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• pp.7-14
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• 2001

The amount of petroleum consumption has been Increased according to the industrialization and It leads to the increase of the possibility of marine oil pollution. In Korea, some countermeasures including oil skimmer, gelling agent and herding agent of oil have been used for the remediation of the pollution. However, most of them have lets of shortcomings in the application under in-situ condition, because they are sensitive to the situation such as geographical feature, the wind and the tide. In reported literature, the natural powdered oil absorbent which is made of peat moss is an effective mean to clean spilled oil from lake or coast. However, the peat moss is a natural resource which is only Produced from a specific cold weather are like Canada. This indicates that the alternative materials which is readily obtained from everywhere are needed for powdered oil absorbent. Therefore. in the study, same natural materials including pine leaves and straw are tested as the alternative materials for the absorbent. The raw materials were dried and treated by heat at various temperature during several Periods and then. shattered by a grain cracking machine. The oil sorption capacity of the prepared materials was compared according to the methods of heat treatment and their sizes. The proportion of hydrogen cyanide to combustion of the absorbents was measured to confirm their final disposal methods. The biodegradability test of the absorbents was carried our to evaluate possibility of a side pollution in the coast. In was found that the heat treatment of pine leaves enhanced the capacity of oil sorption and decreased the water sorption. The maximum oil sorption was observed for the material treated at 18$0^{\circ}C$for 60 min. The amount of hydrogen cyanide from the combustion were 0.09ml/g, 0.07ml/g for pine leaves and straw respectively meaning that the final disposal by combustion might be feasible. The amount or organic carbon extracted from pine leaves during 7 days was up to 0.015g organic carbon from one gram of pine leaves. but the degradation was as fast as for glucose. It is concluded that the pine leaves can be served as a good raw material for the powdered oil absorbent like peat moss.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.35 no.6
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• pp.641-648
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• 2011

Off-gases emitted from the anode of a molten carbonate fuel cell (MCFC) at high temperatures for power generation are used as fuel in catalytic combustion. The heat generated in the catalytic combustor is utilized as the heat for the endothermic reaction required for steam reforming. Among the various operational conditions of the integrated reactor, we varied the inlet gas compositions of the catalytic combustor according to fuel utilization in the MCFC and the ratio of steam to carbon in the reformer. Subsequently, the thermal behaviors and reaction characteristics of the integrated reactor were investigated experimentally. The fundamental data from this experimental study will be useful for the design and fabrication of a more practical integrated reactor in the future.

• Fire Science and Engineering
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• v.27 no.5
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• pp.44-56
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• 2013

This research is to identify how much toxic combustion gases are produced from Korea standardized real fire test (Class A&B) by using Room Corner Tester (RCT) and how much those gases are possibly dangerous to testing personnel by estimating the level of carboxyhemoglobin (% COHb). It is confirmed that testing personnel can be affected as more than 40% COHb from Class A 9th and 10th rating in respiration minute volume (RMV) 2 and from Class A 5th to Class A 10th rating in RMV 3 during the time for initial three minutes. Also, in the case of Class B real fire tests, although it is considered rather safe for the initial 1 minute, testing personnel can be affected as more than 20% COHb from Class B 16th to 20th rating in RMV 3 during total test time. Currently, the Korea standard is only focusing on the protection measures against the heat, but the it is neglecting the protection measures against toxic combustion gases. Therefore, according to this study, it is strongly recommended that testing personnel should wear a self-contained breathing apparatus, or the equivalence depending on the real fire test rating.

• Fire Science and Engineering
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• v.20 no.2 s.62
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• pp.1-7
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• 2006

The aim of the research is to estimate the effect of smoke and combustion gases on humane body indirectly through measuring the toxicity of those. For this purpose, the toxic index of smoke and combustion gases was investigated by smoke hazard test and analysis of smoke which were conducted by KS F 2271 and NES 713 method respectively. It i s proved by KS F 2271 method that PASCON trough is suitable to the testing standard of interior material and construction of building. In addition, it is identified by NES 713 method that combustion gases occurring in PASCON product were only carbon dioxide and carbon monoxide, and the smoke index of those was 0.944. This value means that the hazard effect of smoke gases on humane ! body can possibly happens when exposed to the smoke gases for more than 30 min. In aspect of the domestic situation that have not regulated the hazard estimation and the emissions of smoke when the flame retarding ability of the products have been requested, the toxic indexes of PASCON products are comparatively low.

• Journal of the Korean Society of Propulsion Engineers
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• v.17 no.6
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• pp.67-74
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• 2013

IGCC(Integrated Gasification Combined Cycle) system is candidates which can solve the environmental problems including global warming, since it can be easily combined with CCS(Carbon Capture System). In this research, combustion instability characteristics were studied at various fuel which are composed of $H_2/CH_4/CO$ mixture. Mode analysis for instabilities observed experimentally was conducted and the linearly increasing tendency of frequency was observed as the hydrogen content in fuel increases.

• Journal of the Korean Society of Safety
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• v.26 no.4
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• pp.111-119
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• 2011

This study was designed to provide basic data applicable to fire investigation through consideration of combustion products and propose vulnerability of combustibles through analysis of $CO_2$ emission. In order to achieve these research objectives, characteristics of combustion products such as smoke release rate of each part(raw leaves, branches and barks), $CO_2$ emission and ash production were considered targeting on 6 oak species(Quercus variabilis Blume, Quercus aliena Blume, Quercus serrata, Quercus mongolica Fisch, Quercus dentata Sapling and Quercus acutissima) using cone calorimeter and smoke density tester. As a result, it was found that raw leaves release smoke more relatively than branches and barks, when they burn, and that Quercus variabilis Blume has the highest smoke density. Also, Quercus acutissima released CO and $CO_2$ which are respectively, 6.67 times and 1.43 times more than Quercus variabilis Blume with low $CO_2$ emission. In addition, branches released CO and $CO_2$ more relatively. There was a big difference in ash production among raw leaves(3.1 g), branches(10.5 g) and barks(16.43 g). It was identified that Quercus serrata produces ashes which are nearly 9.95 times more than Quercus variabilis Blume. It demonstrates that Quercus serrata contains relatively higher minerals and that Quercus variabilis Blume can leave lots of traces like stain and carbonization, as it releases smoke a lot and it's difficult to predict visibility, when a forest fire breaks out in its community area. It is also considered that smoke particles containing oil in the air leave strain on the surface of a tree, and that CO and $CO_2$ emission increases, when crown fire to burn branches breaks out.

• Journal of the Korean Institute of Gas
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• v.20 no.1
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• pp.1-6
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• 2016

In order to reduce the anthropogenic emission of greenhouse gases, CCS technology has emerged as the most promising and practical solution. Among CCS technology, post-combustion $CO_2$ capture is known as the most mature and effective process to remove $CO_2$ from power plant, but its energy consumption for chemical solvent regeneration still remains as an obstacle for commercialization. In this study, a process alternative integrating $CO_2$ capture with compression process is proposed which not only reduces the amount of thermal energy required for solvent regeneration but also produces $CO_2$ at an elevated pressure.

• New & Renewable Energy
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• v.19 no.1
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• pp.1-11
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• 2023

A large amount of carbon monoxide (CO) is generated in circulating fluidized bed combustion, the process whereby a hot cyclone separates unburned fuel. However, calcium sulfate (CaSO₄), when combined with a high CO content, can cause fouling on the surface of the steam tube installed inside the integrated recycle heat exchangers (INTREX). In this study, CaSO₄ decomposition was investigated using 0.2-3.2 vol.% CO and 1-3 vol.% oxygen (O₂) at 850℃ for 20 min in a lab-scale fluidized bed reactor. The results show that CaSO₄ decomposes into CaS and CaO when CO gas is supplied, and SO₂ emissions increase from 135 ppm to 1021 ppm with increasing CO concentration. However, the O₂ supply delayed SO₂ emissions because the reaction between CO and O₂ is faster than that of CaSO₄; nevertheless, when supplied with CaCO₃, the intermediate product, SO₂ was significantly released, regardless of the CO and O₂ supply. In addition, agglomerated solids and yellow sulfur power were observed after solid recovery, and the reactor distributor was corroded. Consequently, a sufficient O₂ supply is important and can prevent fouling formation on the INTREX surface by suppressing CaSO₄ degradation.