• 제목/요약/키워드: Reaction rates

검색결과 1,362건 처리시간 0.03초

$CH_{4}$ 제트 화염의 NOx 배출 특성에 관한 수치 및 실험적 연구 (Numerical and Experimental Investigation on NOx Emission Characteristics of $CH_4$ Jet Flame)

  • 박정배;김종현;이창언
    • 한국연소학회:학술대회논문집
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    • 한국연소학회 2000년도 제21회 KOSCO SYMPOSIUM 논문집
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    • pp.67-76
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    • 2000
  • Experimental and numerical investigation on NOx emission characteristics with equivalence ratios, fuel flow rates and nozzle diameters were studied in CH4 Jet flames. Emission indices of NOx were measured by chemiluminescent method with carbon converter. Numerical analyses were carried out with GRl-2.11 mechanism that includes C2-chemistry and all of NO reaction mechanisims. The roles of thermal NO and prompt NO mechanism on each flame's NOx emission index were investigated. The results of this study show that the numerical results represent well the trends of ElNOx experimentally observed. The numerical analyses clarified the trends of EINOx with equivalence ratios, fuel flow rates and nozzle diameters.

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7075 및 7050 알루미늄 합금의 응고 거동 및 편석에 미치는 냉각 속도의 영향 (The Effect of Cooling Rate on the Solidification Behavior and Segregation of 7075 and 7050 Aluminum Alloys)

  • 최정윤;권영동;이주원;이진형
    • 한국주조공학회지
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    • 제21권6호
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    • pp.343-349
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    • 2001
  • The effect of cooling rate on the solidification microstructure and segregation behavior of 7075 and 7050 aluminum alloy was investigated. Samples were solidified with cooling rates from 0.3 to $17^{\circ}K/sec$. Using the cooling curves of each sample, liquidus, eutectic and intermetallic reaction temperatures were estimated. The microstructures were characterized in terms of dendrite arm spacing and eutectic volume fraction. The segregation behavior of each alloying element of these alloys in various cooling rates was discussed.

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야간작업자의 작업부담경감을 위한 휴식방법 (A Study of Methods of Rest for Reduction of The Night Shift Workers′Workload)

  • 김대호;박근상
    • 산업경영시스템학회지
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    • 제23권57호
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    • pp.1-10
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    • 2000
  • The purpose of this paper is to propose a method of rest to reduce work load of night shift workers for night shift work. The experiment was carried out 10minutes preparing time, 45minutes first work, 10minutes first rest, 45minutes second work, 10minutes second rest between 2 and 4 o'clock that the lowest physiological function of workers. The methods of rest set up as four patterns (1) non-action rest (2) non-action rest + listening music (3) action rest + non-action rest, (4) action rest + non-action rest + listening music. For the measurements of experiment, heart rates(R-R interval), critical flicker fusion frequency(CFF), blood pressure, oral temperature, reaction time and error rates were considered as criteria for work performance. As a result, action rest + non-action rest and action rest + non-action rest + listening music were more effective to reduce work load additional work than non-action rest and non-action rest + listening music.

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고온 태양열 화학 반응기의 열전달 성능 분석 (Analysis of Heat Transfer Performance for a Solar Chemical Reactor)

  • 정영국;이주한;서태범
    • 한국태양에너지학회:학술대회논문집
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    • 한국태양에너지학회 2009년도 춘계학술발표대회 논문집
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    • pp.55-60
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    • 2009
  • The purpose of the research is to develop the high performance solar chemical reactor for producing hydrogen using steam reforming reaction of methane. A specific shape chemical reactor is suggested: spiral type reactor. The reactor is installed on the dish-type solar thermal system of Inha University. The temperatures, $CH_4$ conversion rates are measured. At specific condition, $CH_4$ conversion rates of the spiral type reactor are about 92%. The spiral type reactor gives reasonably good performance without any problems caused by highly concentrated solar radiation.

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Sulfuric Acid Leaching of Valuable Metals from Spent Petrochemical Catalyst using Hydrogen Peroxide as a Reducing Agent

  • Park, Kyung-Ho;Sohn, Jeong-Soo;Kim, Jong-Seok
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2001년도 The 6th International Symposium of East Asian Resources Recycling Technology
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    • pp.478-481
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    • 2001
  • The spent petrochemical catalyst used in the manufacturing process of terephthalic-acid contains valuable metals such as cobalt and manganese. To recover these metals, sulfuric acid leaching was performed with hydrogen peroxide as a reducing agent. Low extractions of Mn, Co and Fe were obtained by sulfuric acid leaching without reducing agent. With adding hydrogen peroxide as a reducing agent, the high extraction of these metals could be obtained. Different from general leaching experiment, the extraction rates of metal components were decreased with increasing reaction temperature in this case. Under the optimum condition, the extraction rates of Mn, Co and Fe were 93.0%, 87.0% and 100% respectively.

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강상에 니켈-아연-인 삼원 합금도금에 관한 속도론적 연구 (A Kinetic Study on the Electrodeposition of Ni-Zn-P Ternary Alloys onto a Steel)

  • 안종관;이응조
    • 한국표면공학회지
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    • 제28권4호
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    • pp.199-206
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    • 1995
  • A kinetic study on the electrodeposition of Ni-Zn-P ternary alloys onto a steel in chloride solutions was carried out using a rotating disc electrode. The coatings were characterized using SEM/EPMA and A. A. analysis. The results showed that the plating rates of three components were increased with applied potential, disc rotating speed and temperature. The activation energies of Ni, Zn and P of the coatings were 6.1, 5.1 and 8.0 kcal/mole respectively. Therefore, the deposition rates were controlled partly by surface electrochemical reaction and partly by mass transport. As the potential, temperature of bath and rotating speed of cathode disc were raised, the vol. % ratios of Ni and P of coating layer were increased but that of Zn decreased. The effect of coating parameters on the surface morphology was also examined.

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Preparation of Novel Iron Phthalocyanine Containing Reactive Groups and its Deodorizing Property on Cellulose

  • Kim, Eun-Mi;Choi, Jae-Hong
    • 한국염색가공학회지
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    • 제25권4호
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    • pp.247-253
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    • 2013
  • The enzyme-like catalytic functions of metal complex phthalocyanine derivatives those containing carboxylic acid groups could be applied as odor-removing systems and antibacterial systems. Pyromellitic dianhydride and 4-nitrophthalimide were used as starting material for synthesizing dinitro-tetracarboxylic acid iron phthalocyanine(compound 1). Then diamino-tetracarboxylic phthalocyanine(compound 2) was obtained by reduction of compound 1. For the formation of covalent bond with cellulose fiber, cyanuric chloride was introduced to the amino group of compound 2 by condensation reaction compound 3. The exhaustion method was employed for adsorbing compound 3 on cotton fiber. K/S values of each fabrics were measured by a CCM system and deodorizing rates were tested by a detector tube method for ammonia gas. K/S values of treated cotton fiber with compound 3 were arranged from 2.1 to 4.2 at $90^{\circ}C$ of exhaustion temperature. Deodorizing rates provided result of 81%, 84%, 88%, 91%, by passing time of 30 min, 60 min, 90 min, 120 min, respectively.

유도 결합형 Cl$_2$계 플라즈마를 이용한 GaN 식각 특성에 관한 연구 (A study of the GaN etch properties using inductively coupled Cl$_2$-based plasmas)

  • 김현수;이재원;김태일;염근영
    • 한국표면공학회지
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    • 제32권2호
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    • pp.83-92
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    • 1999
  • GaN etching was performed using planar inductively coupled $Cl_2$-based plasmas and the effects of main process parameters on the characteristics of the plasmas and their relations to GaN etch rates were studied. Also, the GaN etch mechanism was investigated using a Langmuir probe and optical emission spectroscopy (OES) during the etching, and X-ray photoelectron spectroscopy (XPS) of the etched surfaces. The GaN etch rates increased with the increase of chlorine radical density and ion energy, and a vertical etch profile haying the etch rate close to 4000 $\AA$/min could be obtained. The addition of 10% Ar to $Cl_2$ gas increased the GaN etch rate and the addition of Ar (more than 20%) and HBr generally reduced the GaN etch rate. The GaN etch rate appeared to be more affected by the chemical reaction between Cl radicals and GaN compared to the physical sputtering itself under the sufficient ion bombardments to break GaN bonds.

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아조벤젠 유도체의 이성질화 반응속도에 관한 연구 (A Study of the Isomerization Reaction Rates of Azobenzene Derivatives)

  • 양시영;김종규;허영덕;최영상
    • 대한화학회지
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    • 제38권8호
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    • pp.552-561
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    • 1994
  • 아조벤젠 유도체의 시스→트란스 열적 이성질화 반응을 연구하였다. 밀고-당기는 아조벤젠은 이성질화 반응속도의 용매효과가 큼이 확인되었고 이러한 현상으로 밀고-당기는 아조벤젠은 회전 메카니즘에 의해서 이성질화 반응이 일어남을 알 수 있다. 밀고-당기는 아조벤젠이 아닌 화합물은 이성질화 반응속도의 용매효과가 거의 없음이 관찰되었으므로 반전 메카니즘에 의해서 이성질화 반응이 일어남을 확인하였다.

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구리(Ⅱ)-아민류 착물에 의한 l-ascorbic acid의 산화반응속도와 메카니즘 (Rates and Mechanism of the Oxidation of l-Ascorbic Acid with Cu(Ⅱ)-Polyamine Complexes)

  • 김선덕;박정은;장기호;신한철;김창수
    • 대한화학회지
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    • 제39권1호
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    • pp.29-34
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    • 1995
  • 구리(II)-아민류 착물에 의한 l-ascorbic acid의 산화반응속도를 pH 4.6에서 Onishi 방법으로 측정하였다. 이 반응의 메커니즘은 l-ascorbic acid가 구리(II) 착물에 배위된 다음 속도결정단계에서, 전자이동이 일어나는 내부권 메커니즘에 따라 반응이 진행됨을 알았다.

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