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methods to monitor in MM patients in any stages. Differential scanning calorimetry (DSC) is unsurpassed for understanding the stability of biological systems. DSC directly measures the stability and unfolding of a protein, lipid, or nucleic acid

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Journal of Thermal Analysis and Calorimetry
Authors: Jiawu Gao, Lin Li, Yanping Deng, Zongming Gao, Changhua Xu, and Mingxi Zhang

Abstract  

A new method for determining the degree of conversion of gelation (αgel) and gel time (t gel) at gel point using a single technology, DSC, is discussed in this work. Four kinds of thermoset resins are evaluated. It is found that the mutation points of reduced reaction rate (V r) vs. reaction conversion (α) curves, corresponding with the changes of reaction mechanism, represents the gelation of the reaction. The α at the mutation point is defined as αgel. From isothermal DSC curves, the point at αgel is defined ast gel. Traditional techniques (ASTM D3532 and DSC method) are also used to determine αgel andt gel in order to demonstrate this new method. We have found that the results obtained from this new method are very consistent with the results obtained from traditional methods.

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A bioluminescent derivative of Bacillus subtilis containing a plasmid encoding a luxAB fusion under control of a vegetative promoter and gives bioluminescence upon addition of an exogenous long-chain aldehyde has been used as test organism. Its spore populations have been produced and their heat- and radiation survival curves established. Heat-sensitization effect of pre-irradiation of spores was proven not only by colony counting but also with differential scanning calorimetry. Under a linearly programmed temperature increase, the heat destruction of spores surviving 2.5 kGy gamma irradiation resulted in at a few centigrade lower temperature than that of untreated spores. Heat denaturation endotherms in the DSC-thermogram of irradiated spores were shifted to lower temperatures as well. Comparative turbidimetric, luminometric and phase-contrast microscopic studies of untreated, heat-treated and irradiated spore populations showed that the kinetics of germination and the light emission during germination of radiation-inactivated spores were the same as those of untreated spores, revealing that the pre-formed luciferase enzyme packaged into the spores during sporulation remained intact after an irradiation dose causing 90% decrease in number of colony forming spores. Therefore, in contrast to heat-treated spores, the initial bioluminescence reading upon germination of irradiated spores does not reflect the viable count of their population.

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. Differential scanning calorimetry (DSC) can be used to determine melting temperature ( T m ), glass transition temperature ( T g ), crystallization temperature ( T c ) and is also the easiest and most widely used thermal analysis technique in the world. Dynamic

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crystallization kinetics and thermal stability of Se 80− x Te 20 Zn x ( x = 2, 4, 6, 8, and 10) glassy systems have been investigated using differential scanning calorimetry (DSC) at five different heating rates, i.e., 10, 20, 30, 40, and 50 K/min. Accordingly

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electrospun fibers of different solvents were investigated by Differential scanning calorimetry (DSC) analysis and compared with PCL powder. The DSC curves were shown in Fig. 9 . Both PCL powder and electrospun PCL (in different solvents) fibers showed quite

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) reaction [ 6 ], and is employed to provide free-radical in frontal polymerization [ 7 ]. In the past, using differential scanning calorimetry (DSC) and vent scanning package 2 (VSP2), calorimetric approaches for analyzing the crucial thermokinetic

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architectural materials, electronics, and electric insulators [ 12 ]. Our aim was to apply differential scanning calorimetry (DSC) and VSP2 to confirm the thermokinetic parameters, such as maximum temperature ( T max ), onset temperature ( T 0

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temperature ( T 0 ), heat of decomposition (Δ H d ), maximum temperature ( T max ), maximum pressure ( P max ), self-heating rate (d T d t −1 ), pressure rise rate (d P d t −1 ), etc., by using differential scanning calorimetry (DSC) and vent sizing package

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