E. coli. An E. coli RNA polymerase is composed of five subunits: two Î± subunits, and one for each Î², Î²', and Ï subunit. Î² (151 kD) and Î²' (156 kD) are significantly larger than Î± (37 kD). Several different forms of Ï subunits have been identified, with molecular weights ranging from 28 kD to 70 kD.n E. coli RNA polymerase is composed of five subunits: two Î± subunits, and one for each Î², Î²', and Ï subunit. Î² (151 kD) and Î²' (156 kD) are significantly larger than Î± (37 kD). Several different forms of Ï subunits have been identified, with molecular weights ranging from 28 kD to 70 kD.
Probably everybody agrees with the statement that Tg is one of the temperatures within a glass transition region where the metastable melt transforms into glass in the course of its cooling and where glass transforms into metastable melt in the course of heating.
For each of the techniques highlighted, various factors can affect Tg. For DSC, the heating rate and sample heat history are a couple of factors that may affect the test result. For materials that have broad Tgs, DSC may not be sensitive enough to show a large enough transition for accurate calculation purposes.