• Title/Summary/Keyword: Total Heat Release

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Physical Properties and Flame Retardency of Polyhydroxyamides (PHAs) Having Pendant Groups in the Main Chain (주사슬에 곁사슬기를 갖는 폴리히드록시아미드의 물성 및 난연특성)

  • Yoon, Doo-Soo;Choi, Jae-Kon;Jo, Byung-Wook
    • Polymer(Korea)
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    • v.30 no.6
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    • pp.478-485
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    • 2006
  • Physical properties and flammability of polyhydroxyamides (PHAs) haying poly (ethylene-glycol) methyl ether (MPEG) and/or dimethylphenoxy pendants were studied by using DSC, TGA, FTIR, pyrolysis combustion flow calorimeter (PCFC), and X-ray diffractometer. The degradation temperatures of the polymers were recorded in the ranges of $276{\sim}396^{\circ}C$ in air. PCFC results showed that the heat release (HR) capacity and total heat release (total HR) values of the PHAs were increased with in-creasing molecular weight of MPEG. In case of M-PHA 2 annealed at $290^{\circ}C$, the values of HR capacity were siginificantly decreased from 253 to 42 J/gK, and 60% weight loss temperatures increased from 408 to $856^{\circ}C$ with an annealing temperature. The activation energy for the decomposition reaction of the PHAs showed in the range of $129.3{\sim}235.1kJ/mol$, which increased with increasing conversion. Tensile modulus of PHAs were decreased as increasing chain of MPEG, and showed an increase more than initial modulus after converted to PBOs.

A Study on the Fire Hazard of Transportation Oil (수송기관용 오일의 화재위험성에 관한 연구)

  • Park, Young Ju;Hwang, Me Jung;Lee, Hae Pyeong;Lee, Seung Chul;Lee, Chang Hyun
    • Journal of the Korean Society of Safety
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    • v.29 no.3
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    • pp.114-120
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    • 2014
  • The purpose of this study is to conduct the study of the combustion and thermal characteristics through transportation oil for the analysis of fire hazard. Transportation oil breaks down into fuels such as diesel for civilian demands, gasoline, DF1(diesel for military), high sulfur diesel(for marine), kerosene and JP1(for aviation), and lubricants like brake fluid, power steering oil, engine oil, and automatic and manual transmission oil. The experiments of flash point, ignition point, flame duration time, heat release rate were carried out using TAG closed cup flash point tester(AFP761), Cleveland open cup auto flash point analyzer(AFP762), KRS-RG-9000 and Dual cone calorimeter. As a result, the fuel's ignition points were lower than lubricants, especially that of gasoline was not conducted as it has below zero one. Gasoline has the highest ignition point of about $600^{\circ}C$, while the other fuels showed $400{\sim}465^{\circ}C$. For flame duration time, lubricants had over 300 seconds, but fuels had less than 300 seconds except high sulfur diesel(350 seconds). Total heat release rate ranged $287{\sim}462kW/m^2$ for lubricants and gasoline showed the highest total heat release rate, $652kW/m^2$.

The Heat Release Rate Comparison of Subway car's Interior Materials using Cone Calorimeter (콘칼로리미터를 이용한 도시철도차량 내장재료별 발열량 비교)

  • Lee Cheul-kyu;Lee Duck Hee;Jung Woo Sung
    • Proceedings of the KSR Conference
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    • 2005.05a
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    • pp.70-76
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    • 2005
  • The interior materials of the urban subway car in operation are now being changed to new materials that meet the latest law in effect, the fire safety criteria of the urban railway vehicle. It was well known fact that the composite materials, that were applied to last subway car, were weak on the fire. Contrary to this materials, materials in work have good resistance to the fire. On the paper, To investigate the difference of fire safety level on the subway car, cone calorimeter was used to measure the heat release rate and total heat released according to the ISO 5660. A high radiative heat flux of 50kW/m2 was used to burn out all materials and to simulate the condition of fully developed fire case in the tests.

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A Comparison of the Immediate Effects of Alternate Methods to Medication in Lowering the Blood Pressure in Prehypertensive Patients

  • Moon, Hyun-Ju;Cho, Sung-Hak
    • The Journal of Korean Physical Therapy
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    • v.28 no.3
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    • pp.201-204
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    • 2016
  • Purpose: The purpose of this study was to compare the immediate effects of alternative treatment methods in lowering the blood pressure and pulse of prehypertensive patients. Methods: A total of 48 prehypertensive patients were randomly divided into 4 groups of 12 patients and each group received a different intervention. The control group was made to rest, the heat pack (HP) group received heat pack treatment, the ultrasound (US) group received an ultrasound massage, and the myofascial release (MFR) group received myofascial release. The blood pressure and pulse rate were measured before and after intervention. Results: Following intervention, the patients of the MFR group showed a decrease in systolic pressure, diastolic pressure, and pulse rate. Although blood pressure was similar in all groups, a significant decrease in pulse rate was seen in the MFR group compared to others. Conclusion: The application of MFR was shown to be an effective method for lowering the blood pressure and pulse rate in prehypertensive patients.

A Cost Analysis of the Heat Recovery Ventilator under Various Condition (열회수형 환기장치의 운전조건에 따른 경제성 평가에 관한 연구)

  • Kang, Tae-Wook;Koh, Jae-Yoon
    • Journal of the Korean Solar Energy Society
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    • v.26 no.1
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    • pp.21-28
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    • 2006
  • Changes in building construction methods and repairing of older buildings have reduced infiltration rate. Synthetic materials, release airborne particles and uneven healthy odor are increased. For preventing pollutants introduce fresh outdoor air into the building, simply letting fresh outdoor air into building, however, Is not a cost-effective way to ventilation. When additional ventilation is added to an existing HVAC system, the heating and cooling equipment, often cannot handle the increased load. A HRV provides a way to minimize in energy costs while introducing fresh air to a building. In this study, the economical research of HRV, made of three types of materials, are conducted. Heat recovering characteristics are studied at seasonal outdoor air conditions based on the outdoor air property condition at, Seoul in 2002. As a results, the average sensible effectiveness is 0.75 in the sensible heat exchanger and average total effectiveness is 0.65 in the total heat exchanger. The pay back period of the sensible heat exchangers are $3.2{\sim}3.5$ year and it of total heat exchanger is 2.2 years.

Combustion Characteristics of the 5 Herb Species in Youngdong Areas (영동지역 5개 초본 수종의 연소특성)

  • Lee, Hae Pyeong;Lee, Si-Young;Park, Young Ju
    • Journal of Korean Society of Forest Science
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    • v.98 no.3
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    • pp.290-296
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    • 2009
  • In this study, we considered the combustion of the various herbs in youngdong areas such as festuca ovina, isodeon japonicus, oplismenus undulatifolius, pueraria thunbergiana, and cirsium japonicum var. ussuriense using the ignition temperature tester, cone calorimeter, smoke density chamber. We confirmed that the range of ignition temperature was $400{\sim}455^{\circ}C$ and the time to ignition and flameout were not recorded. The total heat release of isodeon japonicus was highest and the smoke release of festuca ovina was highest, and the yield of CO and $CO_2$ of pueraria thunbergiana, and cirsium japonicum var. ussuriense were highest among the samples. As a result, we concluded that isodeon japonicus will impact the fire intensity and fire spread and festuca ovina, pueraria thunbergiana, and cirsium japonicum var. ussuriense will influence the refuge.

Combustion Properties of Major Wood Species Planted in Indonesia (인도네시아 주요 조림수종의 연소특성)

  • Park, Se-Hwi;Jang, Jae-Hyuk;Hidayat, Wahyu;Qi, Yue;Febrianto, Fauzi;Kim, Nam-Hun
    • Journal of the Korean Wood Science and Technology
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    • v.43 no.6
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    • pp.768-776
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    • 2015
  • This study was performed to understand combustion properties four major Indonesian wood species such as Albizia, Gmelina, Mangium and Mindi were investigated by cone-calorimeter for better utilization of theses wood species. Heat release rate (HRR), total heat release (TSR), specific mass loss rate (SMLR), effective heat of combustion (EHC), time to ignition (TTI), flame time (FT), specific extinction area (SEA), smoke production rate (SPR) and CO compound production rate were measured. HRR, THR and FT were proportional to the density of woods. Albizia showed the highest HRR, while Mindi had the lowest HRR. For SPR, Albizia showed the highest value due to its higher SEA. On the other hand, Mindi had the lowest SPR due to a lower SEA value. The highest smoke emission was for Albizia at the beginning of combustion. After 300 seconds, smoke emission of Gmleina and Mangium was increased greatly. Mangium and Mindi showed the highest total carbon dioxide emission. Expecially, Gmelina released the highest carbon monoxide during the combustion period and presented three times higher $CO/CO_2$ ratio than those of other species due to incomplete combustion.

Combustion Characteristics of Bamboo Charcoal Boards (대나무숯 성형보드의 연소특성)

  • Park, Sang-Bum;Park, Joo-Saeng
    • Journal of the Korean Wood Science and Technology
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    • v.40 no.1
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    • pp.19-25
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    • 2012
  • The fire retardant bamboo charcoal (BC) boards were manufactured for interior building materials in this study, The BC boards were manufactured by mixing and pressing of the bamboo charcoal, expanded vermiculite, and inorganic binder. The combustion behaviors of the BC boards were investigated using a cone calorimeter at an incident heat flux of 50 kW/$m^2$. Three building materials (plywood, BC board of Japan, and gypsum board) were used to observe the burning behaviors of weight loss, total heat release rate, and maximum heat release rate. Surface test and toxicity evaluation of the BC board were also conducted. The weight loss of the BC board (12.0%) was lower than the nonflammable gypsum board (15.6%) after burning of 10 min. Total heat release of the BC was 3 MJ/$m^2$ (KS standard 8 MJ/$m^2$) and total heat release rate of the BC was 20 kW/$m^2$ (KS standard 200 kW/$m^2$). Therefore, the BC boards were adjustable for the third-grade flame retardant building materials. External appearance change and mouse toxicity were not found in the BC boards after the combustion test.

Preparation and Properties of Aromatic Polybenzoxazoles with high char yields (높은 char 수득률를 갖는 방향족 polybenzoxazoles의 제조 및 특성)

  • Sohn, Jun-Youn;Moon, Sung-Chul;Yoon, Doo-Soo;Choi, Jae-Kon
    • Elastomers and Composites
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    • v.42 no.4
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    • pp.238-248
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    • 2007
  • A series of polyhydroxyamides(PHAs) having ether linkages in the polymer backbone were prepared via solution polycondensation at low temperature. These polymers were studied by FT-IR, $^1H-NMR$, DSC, TGA and PCFC. The PHAs exhibited inherent viscosities in the range of $0.5{\sim}1.1dL/g\;at\;35^{\circ}C$ in DMAc solution. Most of PHAs except PHA 3 were soluble in polar organic solvents such as N,N-dimethylacetamide(DMAc), N-methyl-2-pyrrolidone(NMP), and N,N-dimethylform-amide(DMF). Subsequent thermal treatment of PHAs afforded polybenzoxazols(PBOs). However, the PBOs were insoluble in a variety of solvents. Most of the PBOs except PBO 3 showed glass-transition temperature($T_g$) in the range of $200{\sim}246^{\circ}C$ by DSC and maximum weight loss temperature in the range of $597{\sim}697^{\circ}C$ in nitrogen by TGA. PBOs showed high char yields in the range of $51{\sim}64%$. PCFC results of the PBOs showed the heat release(HR) capacity, $8{\sim}65J/gK$ and total heat release(total HR), $2.4{\sim}4.7kJ/g$.

A Room-Corner Fire Model을 적용한 건축내장재의 화재확산 특성 평가(1)

  • Kim, Un-Hyeong
    • Fire Protection Technology
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    • s.24
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    • pp.32-39
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    • 1998
  • A room-corner fire scenario of ISO 9705 with flame spread model developed by Quintiere is applied to the interior finish materials to show the sensitivity of properties derived from AST, E-1321 and ASTM E-1354 is investigated and various range of thermal properties by the author were analyzed in the model. There are including flame heat flux and thermal inertia, lateral flame spread parameter, heat of combustion and effective heat of gasfication. The time for total energy release rate to reach 1MW is examined. Though some areas are neede for improvements, The model appears to predict good results with all the range of input properties and could be

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