• The International Journal of Costume Culture
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• 제7권1호
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• pp.40-47
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• 2004

The purpose of this research was to examine the degradation rate of alizarin in accelerated degradation conditions using the GC-MS quantitative analysis. Alizarin dye solution (2.5 x 10/sup -3/ M conc.) were kept in 150℃ oven for total of 7 days and the degradation rate was examined each day. 2.5 × 10/sup -4/M conc. alizarin dye solution was mixed with H₂O₂ according to [H₂O₂]/[dye] ratio 40 and were kept under 365㎚ UV for 2 hours, analyzed after 0, 30, 60, 90, 120min using the GC-MS. Gas chromatogram showed alizarin peak at 9.96 - 10.13 min. retention time range and residual peaks in the wide range from 9.6 to 11.1 min. Oven degradation exhibited an initial decrease in the amount of alizarin, which was followed by increasing amount in 4/sup th/ day. The decrease in the alizarin was significantly shown by the 7/sup th/ day. Same pattern was also observed in the H₂O₂/UV/O₂ degradation samples and was verified ed by the UV-VIS spectra. The differences in the amount of alizarin between 1/sup st/ day and 4/sup th/ day samples, 4/sup th/ day and 7/sup th/ day samples, and Control and 7/sup th/ day samples of the oven degradation were significant at alpha .20.

• 한국안전학회지
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• 제20권4호
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• pp.46-53
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• 2005

Existing study far fire-resistant concrete has been done already. but it is not found out how the waste tyre mixing concrete will be acted against fire. This waste tyre concrete molds under the condition of $0^{\circ}C,\;200^{\circ}C,\;400^{\circ}C,\;600^{\circ}C$ were heated in gas oven. It was worried about that they might be fractured down at about $800^{\circ}C$ so that they can not be tested. compressive strength for the test molds are made with commercially used $180kg/cm^2,\;210kg/cm^2,\;240kg/cm^2,\;270kg/cm^2$ mixing saw dust with proportion such as 0.05%, 0.1%, 0.2%, 0.4%, 0.6%, 0.8%, 1.0%, 1.2%, 1.4%, 1.6%, 1.8%, 2.0% compressive strength at $200^{\circ}C$ was approximately 20% from the original, while approximately 30% deoreased at $400^{\circ}C$. their results are not quite different from the normal concrete condition even though they contains saw dust in it. The higher strength the concrete has, the less strength was decreased. There are almost no difference in strength under the condition of less than $400^{\circ}C$, but damage of concrete structure could be considerable large with more than $400^{\circ}C$.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 추계학술대회 논문집 Vol.16
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• pp.368-371
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• 2003

The humidity sensors with a stable characteristics and gas sensors operating at room temperature have been fabricated, and a multi-functional sensor system which has gas sensor, humidity sensor, temperature sensor and control circuit has been applied to the microwave oven system. For a suitable cooking state, the humidity sensors was more applicable to heating and defrosting condition than gas sensors, however, the dynamic characteristics of gas sensors were obtained in the easy burning food such as pop corn.

• 한국수소및신에너지학회논문집
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• 제33권6호
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• pp.636-642
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• 2022

The "Hydrogen Economic Activation Road map" was announced in 2019, and hydrogen demand is expected to exceed 470,000 tons per year in 2022 and keep increasing. Under this circumstance, it has become important to understand the greenhouse gas (GHG) emissions associated with various hydrogen production pathways. In this study, the evaluation of life cycle GHG emissions regarding the hydrogen produced as by-product from coke oven gas (COG) in steel mill is conducted. To cover the possible range of operations, three literatures were reviewed and their data of inputs and outputs for the process were adopted for calculation. Life cycle inventories and emission factors were mostly referred to GaBi and Intergovernmental Panel on Climate Change (IPCC) guidelines, respectively. When there are multiple products from a single process, the energy allocation method was applied. Based on these sources and the assumptions, the life cycle emission values of COG-based hydrogen were found to be 3.8 to 4.7 kg/CO₂-eq./kg-H₂.

• 미생물학회지
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• 제18권3호
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• pp.148-152
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• 1980

The microwave of 2450 MHz, generated by a household cooking oven, was evaluated for its applicability to melt various rehydrated media and to remove dissolved oxygen from tubed media for anaerobic culture. The effect on the sterilization of E. coli in selective media was also evaluated. The following results were obtained. 10 The microwave oven was useful in saving time for melting media and in eliminating heat and combustion gas from the laboratory, which were inevitable by-products in the conventional flame method. 2) Dissolved oxygen could be removed without boiling over by exposing the tubes of anaerobic culture medium after putting them in a wire basket in a beaker with water. 30 The count of E. coli during the melting of MacConkey and EMB agar were similar to those treated with open flame. The microwave treatment was not considered a possible mean to replace autoclaving even in these selective media.

• 한국에너지공학회:학술대회논문집
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• 한국에너지공학회 1998년도 추계 학술발표회 논문집
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• pp.180-192
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• 1998

One of the conventional gas burners has nowadays been used for ladle preheating. As a ladle is one of the open-type furnaces, however, it causes to consume much fuel because of high temperature of exhaust gas from the ladle and the exhaust gas passing through ladle cover makes it worsen a working environment nearby. Therefore, the objective of this study is to develop the recuperative burner system applying for an existing teeming ladle , which is integrated with burner, recuperator and eductor as one of the new type combustion equipments and has many advantages of simple installation, compactness and easy control, especially a great deal of energy saving through the waste heat recovery from exhaust gas. The contents of the study is to design, manufacture of recuperative burner system and to perform its tests experimentally after applying to the teeming ladle in the capacity of 100 ton. Its heat release rate is 1,700,000 kcal/h with COG(Cokes Oven Gas) as fuel gas. The test items are the temperature distribution inside the ladle and the preheated air temperature change depending upon the exhaust gas. Nox, exhaust gas analysis and noise.

• 한국전기전자재료학회논문지
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• 제24권4호
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• pp.290-296
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• 2011

Carbon nanotubes (CNTs) have excellent electrical, chemical stability, mechanical and thermal properties. In this paper, networks of Multi-walled carbon nanotube (MWCNT) materials were investigated as a resistive gas sensors for the $H_2$ gas detection. Sensor films were fabricated by the air spray method using the multi-walled CNTs dispersion solution on the glass substrates cured with plasma and nitrocellulose. Sensors were characterized by the resistance measurements in the self-fabricated oven in order to find the optimum detection properties for the hydrogen gas molecular. The sensitivity and the linearity of the MWVNT sensors using the glass substrate cured with plasma for the $H_2$ gas concentration of 0.06~0.6 ppm are 0.013~0.097%/sec and 0.131~0.959%FS, respectively. The MWCNT film was excellent in the response for the hydrogen gas moleculars and its reaction speed was very fast, which could be using as hydrogen gas sensor. The resistance of the fabricated sensors decreases when the sensors are exposed to $H_2$ gas.

• 한국가스학회지
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• 제5권2호
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• pp.9-13
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• 2001

광양제철소의 소둔로 설비를 대상으로 정성적 및 정량적 위험성을 평가하였다. 소둔로는 냉연 강판 제조시 품질 향상을 위한 열처리 목적으로 이용되는 제철 설비중 하나로 Coke Oven Gas(COG)가 연료로 사용되고, 수소와 질소의 혼합가스 또는 순수한 수소가 분위기 가스로 사용된다. 위험성 평가를 통하여, 소둔로의 가연성 가스 누출 시나리오와 빈도를 분석하였으며, 가연성 가스 누출 사고시 화재 또는 폭발의 피해 영향을 분석하였다. 이들 분석 결과와 함께 여러 다른 지수(Index)를 제시하여 소둔로 가스 설비의 안전성 향상 방안을 도출하였다.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2006년도 제33회 KOSCO SYMPOSIUM 논문집
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• pp.7-8
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• 2006

As a new type of flame, tubular flame has attracted much attention from a fundamental viewpoint and many experimental and theoretical studies have been made on its characteristics. Recently, it is also recognized that the tubular flame has great potentials as practical combustor because its stability range is very wide in fuel concentration and also in injection velocity. Thus, tubular flame burners have been developed for various kinds of fuels. They are gaseous fuels of methane, propane, hydrogen, and by-product fuels gases in steel making processes including BFG (Blast Furnace Gas), LDG (LD Converter Gas), and COG (Cokes-Oven Gas), liquid fuels of kerosene, A-type and C-type heavy oils, and a solid fuel of biomass powder. In this paper, recent developments of the tubular flame burners have been briefly introduced.

• 대한기계학회논문집B
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• 제23권5호
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• pp.653-660
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• 1999

This work describes analysis on the effect of inlet air cooling by the cold energy of liquefied natural gas(LNG) on the performance of gas turbines. Gas turbine off-design analysis program to simulate the influence of compressor inlet temperature variation is prepared and an inlet air cooler is modeled. It is shown that the degree of power augmentation is much affected by the humidity of inlet air. If the humidity is low enough, that is the water content of the air does not condense, the temperature drop amounts to $18^{\circ}C$, which corresponds to more than 12% power increase, in case of a $1350^{\circ}C$ class gas turbine with methane as the fuel. Even with 60% humidity, about 8% power increase is possible. It is found that even though the fuel contains as much as 20% ethane in addition to methane, the power improvement does not change considerably. It is observed that if the humidity is not too high, the current system is feasible oven with conceivable air pressure loss at the inlet air cooler.