Differential thermal analysis data reporting

P517-L R under refs for BlkPdr and Pyro-dex , and in Vol 6, F63-L to F69 (fig) under Flare. . . , F70-L to F72-R under Flare, German , and the following reported work. When combined, Ba chromate (74-77), Mn (20—22) and S (3—4%) has been used to form gasless powders for (pyrot) delay elements of fuzes (Refs 5, 6, 9, 10 and 16). Baldwin and Wooldridge (Ref 20) report on pyrot dissemination research which has resulted in some press-temp rise and differential thermal analysis data... 

As summarized in Table 7, the yields in solid polyethylene (mp initial 132 °C, final 135 °C, by differential thermal analysis (DTA) cristallinity 85-90%) are very high. The transition metals proposed for this polymerization are Ti, V, Cr, Mn, Fe, Co, Ni, Cu. The results quoted in the patent related to the use of these metals38 are reported in Table 8 chromium and vanadium give the highest yield in solid polyethylene, nickel gives quantitative dimerization to 1-butene, as expected from the bibliographic data related to the chemical activity of these metals. 

The technique of differential thermal analysis (D.T.A.) has been extensively employed in the study of clay and other minerals for elucidating their structures for more than three decades. The application of D.T.A. as a tool has not been widely made to the systematic study of solid catalysts. Only a few references on the subject could be foimd 1-6). In the present article, differential thermal studies of a number of solid catalysts like chromic oxide gels, ferric oxide gels, and chromic oxide-ferric oxide are reported. An attempt has also been made to correlate the data with x-ray... 

In F yires 3.7 and 3.8, various data are shown that illustrate the evolution of the phase composition with increasing calcination temperature, with (pseudo)hoehmite as the starting compound. In Figure 3.7, the evolution of the surface area upon heat treatment of pseudohoehmite is reported in parallel to the differential thermal analysis (DTA) curve and the phase composition in each temperature range is indicated (81). In Figure 3.8 (82), the X-ray diffraction (XRD) patterns and the Al MAS NMR spectra of the products ofboehmite calcination are shown. The XRD pattern ofhoehmite... 

Micro-thermal analysis (pTA ) micro-modulated differential thermal analysis (pMDTA ) and micro-thermomechanical analysis (pTMA M) are registered trade marks of TA Instruments Inc. For the time being little work has been reported using such instruments [12] and the calorimetric data are non-quantitative, so that results from pTA should be interpreted with caution. 

Sato et al. reported that Vectra A950 has a 70/30 molar ratio of pHBA/2,6-HNA [18].TGA data show that the maximum degradation rate(9W/9t)m occurs at 520°C under both helium and quasi-air at 10°C min heating rate. The TGA curves under the two conditions almost superimpose each other below 550°C however, differential thermal analysis (DTA) results show much difference under two atmospheres. Under helium, a weak endothermic peak of ester bond rupture is observed at about 550°C, while no significant peaks exist above 550°C, and, finally, 40% weight remains. In quasi-air, a sharp exotherm happens at about 550°C, and an even larger endotherm occurs at about 600°C. Nearly no weight remains at the end. 

Differential thermal analysis is widely used for determining exotherm and endotherm of reactive substances. It can also be used for determining transition temperatures, such as the glass transition temperature and the melt temperature of polymers (ASTM D3418). ASTM D472 provides directions for reporting thermoanalytical data. 

In practice, the enthalpy of gasification is rarely calculated because detailed and reliable thermodynamic data for the polymer and its decomposition products are generally unavailable. Direct laboratory measurement of Lg using differential thermal analysis and differential scanning calorimetry has been reported, but Lg is usually measured in a constant heat flux gasification device or fire calorimeter (see under Steady Burning). In these experiments a plot of mass loss rate per unit surface area (mass flux) versus external heat flux has slope 1/Lg where... 

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