2000-12-09
org.kosen.entty.User@7c978652
구봉성(bistic)
- 1
endothermic effect (cooling effect) 측정 방법에 대해 알고 싶습니다.
간단히 lab-scale 에서 확인하여 볼 수 있는 방법이 있는지 아니면 어디에 의뢰하여 확인할 수 있는 방법이 있는지 전혀 알지 못해서요..
도움 부탁드립니다..
지식의 출발은 질문, 모든 지식의 완성은 답변!
각 분야 한인연구자와 현업 전문가분들의 답변을 기다립니다.
각 분야 한인연구자와 현업 전문가분들의 답변을 기다립니다.
답변 1
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답변
장영일님의 답변
2000-12-10- 0
DIFFERENTIAL THERMAL ANALYSIS (DTA), DIFFERENTIAL SCANNING CALORIMETRY (DSC)와 같은 열분석 실험장비가 필요합니다. 참고로 몇몇 열분석의 응용분야를 알려 드립니다. 도움이 되기를 바랍니다. -------------- DIFFERENTIAL THERMAL ANALYSIS (DTA) DIFFERENTIAL SCANNING CALORIMETRY (DSC) DIN 51007, DIN 53765, ASTM E 474, ASTM D 3418 These are techniques by which the difference in heat flow to or from a sample and to or from a reference is monitored as a function of temperature or time, while the sample is subjected to a controlled temperature program. Applications: characteristic temperatures identification glass transitions melting and crystallization behavior heat of melting and crystallization purity compatibility polymorphism solid-liquid ratio specific heat capacity reaction behavior heat of reaction reaction kinetics oxidative stability thermal stability -------------- THERMOGRAVIMETRY (TG) DIN 51006, ASTM E 914, ASTM E 1131 This is a technique by which the mass of the sample is monitored as a function of temperature or time, while the sample is subjected to a controlled temperature program. Dm = mass change dm/dt = rate of mass change/decomposition DTG = derivative thermogravimetry DTG Peak = characteristic decomposition temperatures ® identification Tonset = thermal stability composition = moisture content, solvent content, additives, polymer content, filler content dehydration decarboxylation oxidation decomposition ----------------- SIMULTANEOUS THERMAL ANALYSIS This technique combines thermogravimetry with differential thermal analysis or differential scanning calorimetry in one run. - possible to consider the real sample mass at a given temperature in Cp determination - no temperature differences between signals of TG and DTA/DSC measurement ---------------- THERMOMECHANICAL ANALYSIS (TMA) DILATOMETRY (DIL) DIN 51045, ASTM E 831, ASTM D 696, ASTM D 3386 This is a technique by which the dimensional changes of the sample are monitored as a function of temperature or time, while the sample may be subjected to an additional mechanical load. - negligible mechanical load ® dilatometry - constant load ® (static) thermomechanical analysis - oscillating force ® dynamic mechanical analysis DL = length change DL / L0 = relative length change a = coefficient of linear thermal expansion Tg = glass transition temperature expansion/shrinkage/penetration behavior dimensional stability ® design purposes softening/curing behavior volumetric expansion (Þ bulk density) -------------- DYNAMIC MECHANICAL ANALYSIS (DMA) DIN 53513, DIN 53440, ASTM D 4065, ASTM D 4092 This is a thermoanalytical method by which the mechanical behavior of a sample subjected to a specific temperature program is investigated under the effect of a load which changes with time. Determination of the storage and loss moduli and the damping factor of a sample as a function of temperature, time and frequency of an applied oscillating load. >endothermic effect (cooling effect) 측정 방법에 대해 알고 싶습니다. >간단히 lab-scale 에서 확인하여 볼 수 있는 방법이 있는지 아니면 어디에 의뢰하여 확인할 수 있는 방법이 있는지 전혀 알지 못해서요.. > >도움 부탁드립니다..