Step heating technique

In this work, we have presented new experimental 3-phase H-Lw V (Hydrate - Liquid Water- Vapour) equilibrium data for methane and a natural gas clathrate hydrates in the presence of high concentrations of mono-ethylene glycol solutions, generated by a reliable fixed-volume (isochoric), step-heating technique. These data in addition to data from literature have been used to validate the predietive capabilities of a thermodynamic model presented in this work. 

Figure 4.34 DSC curve for beef tallow using the step heating technique...

Conversion of the as-deposited film into the crystalline state has been carried out by a variety of methods. The most typical approach is a two-step heat treatment process involving separate low-temperature pyrolysis ( 300 to 350°C) and high-temperature ( 550 to 750°C) crystallization anneals. The times and temperatures utilized depend upon precursor chemistry, film composition, and layer thickness. At the laboratory scale, the pyrolysis step is most often carried out by simply placing the film on a hot plate that has been preset to the desired temperature. Nearly always, pyrolysis conditions are chosen based on the thermal decomposition behavior of powders derived from the same solution chemistry. Thermal gravimetric analysis (TGA) is normally employed for these studies, and while this approach seems less than ideal, it has proved reasonably effective. A few investigators have studied organic pyrolysis in thin films by Fourier transform infrared spectroscopy (FTIR) using reflectance techniques. - This approach allows for an in situ determination of film pyrolysis behavior. 

Another chapter in this book (Kelley 2002) contains details about the history of the technique and pertinent technical details about its application. These will not be repeated here, except to note that the most common application of the technique for meteorite and lunar studies is step-heating " °Ar- Ar dating. In this application, a sample is irradiated... 

For environmental stressors, reduce contact with the stressor. Use a cool recovery acea to recover from heat, a quiet area to recover from noise, no vibration to recover from vibration. For muscle stressors, it helps to have a good circulation system (to be in good shape). Active rest seems better than passive rest. The active rest may be just walking to the coffee area (blood circulation in the legs improves dramatically within <20 steps). Another technique to get active rest is to have the operator do the material handling for the workstation (obtain supplies, dispose of finished components). 

The effect of °Ar loss during devitrification of the glassy matrix of Kirkpatrick Basalt flows was investigated by Fleck et al. (1977) by means of the step-wise heating technique of the Ar/ Ar method. In preparation of this study, Fleck et al. (1977, p. 19) adopted the following definition of the plateau date ... 

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