1 / 15

The Thermodynamics of Blowin’ Shit Up

The Thermodynamics of Blowin’ Shit Up. Thomas M. Jerant. Cindy D. Spangler. The Method. Differential Scanning Calorimetry A technique in which the difference in the amount of heat required to increase the temperature of a sample and reference as a function of temperature. Heat Flux DSC.

arenee
Download Presentation

The Thermodynamics of Blowin’ Shit Up

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. The Thermodynamics of Blowin’ Shit Up Thomas M. Jerant Cindy D. Spangler

  2. The Method • Differential Scanning Calorimetry • A technique in which the difference in the amount of heat required to increase the temperature of a sample and reference as a function of temperature.

  3. Heat Flux DSC • Heat that is transferred to the sample and reference is the same and temperature differences between the two are measured

  4. Power DSC • Both the sample and the reference are kept at the same temperature while electrical power used by the heaters is monitored

  5. The Method • Applications: • The DSC is used to measure specific heat capacity (100 to 1200oC) and heats of transition as well as to detect the temperature of phase changes and melting points in the range of 20 to 1500oC. Specific heat capacity can be used in conjunction with thermal diffusivity to obtain thermal conductivity.

  6. Determination of Kinetics • Finding the accuracy of activation energy evaluations using the isoconversional method

  7. Kinetic Analysis The decomposition kinetics of a heterogeneous solid state reaction • αis the extent of reaction. • f(α) is the reaction model • k(T) is the temperature-dependent rate constant

  8. Kinetic Analysis To determine Eα, the function S2(Eα), the variance, is minimized. • n is the number of experiments • j and i are indices for heating programs for two separate experiments • J is the Arrhenius integral solved by the trapezoid rule • T(t) is the temperature dependence on time

  9. Kinetic Analysis • α is broken down into 50 segments for the entire process. • The plot of Eα vs. Α is shown below for the nonisothermal DSC trace where β = 10 °C min-1 for the closed pan sample of TNAZ • A built up dependence of α is established for the entire reaction, Af(α).

  10. Results

  11. TNAZ • 1,3,3-trinitroazetidine (TNAZ) is a the only widely used melt castable explosive. • TNAZ can be moulded into the liquid state. • TNAZ is being considered as an alternative for trinitrotoluene (TNT). Heat

  12. Endo Phase Changes

  13. Arrhenius Parameters

More Related