Analysis of freezing in buds of Douglas-fir seedlings by simultaneous detection of ultrasonic emissions and differential thermal analysis

1992 ◽  
Vol 22 (9) ◽  
pp. 1305-1309
Author(s):  
Cecil Stushnoff ◽  
Richard W. Tinus ◽  
Virgil D. Esensee
Keyword(s):  
Thermal Analysis ◽  
Differential Thermal Analysis ◽  
Low Temperatures ◽  
Simultaneous Detection ◽  
Freezing Temperature ◽  
Douglas Fir ◽  
Freezing Injury ◽  
Plant Tissues ◽  
Scanning Calorimetry ◽  
Analytical Technique

Differential thermal analysis is used to detect low-temperature exotherms, the nucleation of supercooled aqueous fractions, indicative of lethal freezing temperature in certain plant tissues. However, in plant tissues that do not supercool at low temperatures, there has been no analytical technique to detect events during lethal freezing. Simultaneous detection of ultrasonic emissions and differential thermal analysis exotherms provides a method to determine the lethal freezing temperature in lateral buds of Douglas-fir (Pseudotsugamenziesii (Mirb.) Franco) seedlings in the nonhardy and in the hardy condition. Ultrasonic emissions were detected in buds that supercooled at low temperatures and in those that did not. Simultaneous detection of ultrasonic emissions and differential thermal analysis is more sensitive than differential scanning calorimetry. Neither the precise source nor the nature of molecular perturbations associated with the release of ultrasonic emissions during freezing injury is known.

scholarly journals A thermal degradation study of Y and La methanesulfonates

2006 ◽  
Vol 71 (8-9) ◽  
pp. 905-915
Author(s):  
Moura de ◽  
Jivaldo Matos ◽  
Farias de
Keyword(s):  
Thermal Analysis ◽  
Differential Scanning Calorimetry ◽  
Differential Thermal Analysis ◽  
Thermal Degradation ◽  
Degradation Process ◽  
Oxide Formation ◽  
Scanning Calorimetry ◽  
Degradation Study ◽  
Thermogravimetric Data ◽  
Thermal Degradation Process

The synthesis, characterization and thermal degradation of yttrium and lanthanum methanesulfonates is reported. The prepared salts were characterized by elemental analysis and infrared spectroscopy. The thermal degradation study was performed using thermogravimetry (TG), differential thermal analysis (DTA) and differential scanning calorimetry (DSC).Using the thermogravimetric data, a kinetic study of the dehydration ofY and Lamethanesulfonates was performed employing the Coats-Redfern and Zsak?methods. It was verified that under heating, yttrium and lanthanum methanesulfonates undergo three main processes: dehydration, thermal degradation and oxide formation. Furthermore, depending on the nature of the atmosphere, i.e., inert or oxidant, the thermal degradation process could be endothermic (N2) or exothermic (air).

scholarly journals Thermal stability and thermal decomposition of sucralose

2018 ◽  
Vol 39 (4) ◽  
pp. 21
Author(s):  
Gilbert Bannach ◽  
Rafael R. Almeida ◽  
Luis G. Lacerda ◽  
Egon Schnitzler ◽  
Massao Ionashiro
Keyword(s):  
Thermal Stability ◽  
Thermal Analysis ◽  
Differential Scanning Calorimetry ◽  
Thermal Decomposition ◽  
Differential Thermal Analysis ◽  
Infrared Spectroscopy ◽  
Scanning Calorimetry ◽  
Thermoanalytical Techniques ◽  
Thermal Stability Of

Several papers have been described on the thermal stability of the sweetener, C12H19Cl3O8 (Sucralose). Nevertheless no study using thermoanalytical techniques was found in the literature. Simultaneous thermogravimetry and differential thermal analysis (TG-DTA), differential scanning calorimetry (DSC) and infrared spectroscopy, have been used to study the thermal stability and thermal decomposition of sweetener.

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