• Elastomers and Composites
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• 제22권4호
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• pp.333-339
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• 1987

A modern kinetic evaluation method for nonisothermal reactions measured with Differential Scanning Calorimetry(DSC) is presented. It is based on multiple linear regression analysis using a number of curve points in a selectable range of conversion. The obtained kinetic data are the basis to compute a reaction process under any condition e.g. isothermal or adiabatic. The DSC measurements was performed on a Mettler TA3000 SYSTEM with the built in evaluation software. Mainly the following reactions are discussed: vulcanization of natural rubber compounds containing vulcanizing accelerators. The purpose of this work is to analyse the vulcanization kinetics of typical NR vulcanization systems using DSC. These systems were chosen because they are typically reactive elastomer and are commercially important.

• BMB Reports
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• 제35권3호
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• pp.302-305
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• 2002

Kinetic and thermodynamic studies have been made on the effect of the inosine product on the activity of adenosine deaminase in a 50 mM sodium phosphate buffer, pH 7.5, at $27^{\circ}C$ using UV spectrophotometry and isothermal titration calorimetry (ITC). A competitive inhibition was observed for inosine as a product of the enzymatic reaction. A graphical-fitting method was used for determination of the binding constant and enthalpy of inhibitor binding by using isothermal titration microcalorimetry data. The dissociation-binding constant is equal to $140\;{\mu}M$ by the microcalorimetry method, which agrees well with the value of $143\;{\mu}M$ for the inhibition constant that was obtained from the spectroscopy method.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2021년도 가을 학술논문 발표대회
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• pp.182-183
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• 2021

In this study, This is the result of thermal characteristics analysis to suggest an efficient method of using coal gasification slag(CGS) of byproduct from integrated gasification combined cycle(IGCC). In Specific Heat characteristics, CGS and CS showed similar values. Isothermal Conduction Calorimetry showed that the hydration reaction of cement was retarded when CGS was used. Therefore, it is expected that CGS will be used as an efficient alternative to reducing the hydration heat of mass concrete as a functional aggregate combination.

• 한국초전도저온공학회:학술대회논문집
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• 한국초전도저온공학회 2003년도 추계학술대회 논문집
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• pp.313-315
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• 2003

The heat loads invaded from the environment to several parts of superconduct cable cooling system were measured by liquid boiloff calorimetry. The measuring system was verified by the measurement to a uniform heat loads. The heat loads by the tubes for relief and pressure gauges were greater than the estimated.

• Asian-Australasian Journal of Animal Sciences
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• 제12권7호
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• pp.1085-1089
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• 1999

Energy requirement of Rhode Island Red (RIR) hens was studied by comparative slaughter technique. Seventeen hens above 72 weeks of age were slaughtered in batches. Batch I consisted of 5 hens which were slaughtered initially. Batch II comprised of six hens, which were fed ad libitum broken rice (BR)-based diet for 18 days. Record of feed intake, number of eggs laid and egg weight during the period was kept. These hens were slaughtered and body energy content was determined. Egg energy was consisted as energy deposited. Batch III consisting of six hens which were fed varying quantity of diet for 15 days, were slaughtered similarly as hens of batch II. Regression equation (body weight to body energy) developed on batch I was applied to batch II and developed on batch II was applied to batch III hens, to find out initial body energy content of hens. Egg energy (EE) was calculated according to formula: EE (kcal) = -19.7 + 1.81 egg weight (g). Regressing metabolisable energy (ME) intake on energy balance (body energy change + egg energy), maintenance ME requirement of hens was found to be $119.8kcal/kg\;W^{0.75}/d$. Multiple regression of ME required for production on energy retained as protein and fat (body plus egg energy) indicated that RIR hens synthesize proteins with an efficiency of 85.5 and fat with an efficiency exceeding 100 percent on BR based diet.

• 폴리머
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• 제24권6호
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• pp.777-786
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• 2000

본 연구에서는 범용 열가소성 수지인 폴리프로필렌 (virgin polypropylene, VPP)과 폴리프로필렌을 주성분으로 하는 재생플라스틱의 난연성을 향상시키기 위하여, 난연제 decabromodiphenyl oxide (DBDPO)와 chlorinated paraffin wax (CPW)를 혼합하여 이것들의 난연 특성을 정량적으로 비교 분석 연구하였다. 난연성 평가 측정으로 콘 칼로리미터 (cone calorimeter, ASTM E1354, ISO 5660), 한계산소지수 측정 (LOI, ASTM D2863, ISO 4589) 등을 사용하였고, 콘 칼로리미터를 이용하여 DBDPO와 CPW의 난연효율을 정량적으로 측정하였다. 콘 칼로리미터의 결과로 난연제의 난연효율을 측정한 결과, DBDPO가 CPW보다는 약 2배의 난연효율을 가지고 있다는 것을 확인하였고, 한계산소지수 측정 결과와 유사한 난연효율을 보임을 확인하였다. 열중량 분석 (TGA) 측정결과 난연제 DBDPO를 첨가하였을 때 약 30~5$0^{\circ}C$의 열분해 온도의 상승을 확인할 수 있었다.

• Composites Research
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• 제33권2호
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• pp.44-49
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• 2020

본 연구에서는 시차주사 열량계(differential scanning calorimetry, DSC)를 이용하여 진공백 성형 공정에 사용되는 탄소 섬유 프리프레그의 경화 거동을 연구하였다. 프리프레그를 이용한 동적주사 시험을 통해 전체 발열량(ΔH_total = 537.1 J/g)을 측정하였고, 130℃~180℃에서 등온주사 시험을 실시하였다. 등온주사 시험의 결과는 온도가 올라감에 따라 발열 반응이 증가되는 것을 확인하였다. 시험 결과를 토대로 수지의 경화 거동을 분석하기 위하여 Kratz 모델을 적용하였다. 서로 다른 경화 사이클로 제작된 평판의 경화도를 경화 예측 모델과 실험값을 비교하였다. 경화 예측 모델은 실험값 대비 3.4% 이하의 오차율을 보여 결과가 잘 부합하는 것을 확인하였다.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2017년도 제48회 춘계학술대회논문집
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• pp.547-553
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• 2017

Differential Scanning Calorimetry(DSC)를 이용하여 파이로점화장치에 사용되는 세 가지 고에너지 물질의 열분석 실험을 수행하였다. DSC 실험 데이터를 이용하여 고에너지 물질의 반응속도식을 추출해내는 이론적 방법을 제안하고 반응속도식 추출을 수행하였다. DSC 실험 결과는 Friedman 등전환법으로 분석되었다. 질량분율에 따른 활성화에너지와 빈도인자를 추출해 내어 반응속도식을 완성하였다. 추출된 반응속도식은 고에너지 물질의 화학반응과정을 몇 단계의 주요단계로 가정하는 형태가 아닌 전체 화학 반응 과정을 나타내는 형태를 갖는다. 이는 기존의 열분석 실험을 통해 추출되는 화학반응속도식 형태에 비해 이론적 측면과 정확성 측면에서 상당한 장점을 갖는다. 도출된 반응속도식을 이용하여 실제 추진기관에 운용되는 세 가지 고에너지 물질의 성능변화를 20년에 대하여 예측하였다.

• 한국지하수토양환경학회지:지하수토양환경
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• 제22권5호
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• pp.40-47
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• 2017

The effects of ultrasound in heterogeneous system were investigated in three kinds of ultrasonic systems including a bath-type system (System #1), a double-bath-type system (System #2), and a double-bath-type system partly filled with glass beads (System #3). The ultrasound energy and its attenuation were quantified using calorimetry and the sound pressure measurement method. The sonochemical effects mainly involved in radical oxidation reactions were quantified using KI dosimetry. It was found that ultrasound energy was significantly attenuated in System #2 and #3 due to the presence of solid materials such as a submerged stainless steel reactor and glass beads. However, in spite of low ultrasound energy status, sonochemical oxidation reactions occurred more violently due to the presence of glass beads in System #3. In addition, calorimetry was more adequate to estimate the total energy status of ultrasound in sonoreactors compared to the sound pressure measurement method.

• BMB Reports
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• 제35권5호
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• pp.472-475
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• 2002

Phaseolus vulgaris phytohemagglutinin L is a homotetrameric-leucoagglutinating seed lectin. Its three-dimensional structure shows similarity with other members of the legume lectin family. The tetrameric form of this lectin is pH dependent. Gel filtration results showed that the protein exists in its dimeric state at pH 2.5 and as a tetramer at pH 7.2. Contrary to earlier reports on legume lectins that possess canonical dimers, thermal denaturation studies show that the refolding of phytohemagglutinin L at neutral pH is irreversible. Differential scanning calorimetry (DSC) was used to study the denaturation of this lectin as a function of pH that ranged from 2.0 to 3.0. The lectin was found to be extremely thermostable with a transition temperature around $82^{\circ}C$ and above $100^{\circ}C$ at pH 2.5 and 7.2, respectively. The ratio of calorimetric to vant Hoff enthalpy could not be calculated because of its irreversible-folding behavior. However, from the DSC data, it was discovered that the protein remains in its compact-folded state, even at pH 2.3, with the onset of denaturation occurring at $60^{\circ}C$.