The purpose of the work was to characterize the thermomechanical behaviour of two well-known and widely-used thermoplastic polymers. Both dynamic and constant load measurements were made for high-density polyethylene (HDPE), low-density polyethylene (LDPE) and amorphous polystyrene (PS). The results of these measurements yield valuable information which can aid in both design applications and material processing.
A new DSC system has been developed which not only allows quantitative results in the temperature of −160‡C to 700‡C, but also allows the quantitative determination of a variety of material properties up to 1500‡C. For example, the specific heat of materials can be measured to at least 1400‡C, while enthalpies, etc. can be measured to 1500‡C.
Authors:M. Mason, V. Spate, J. Morris, C. Baskett, T. Cheng, C. Reams, L. Le Marchand, B. Henderson, and L. Kolonel
There is currently great interest in iodine as a micro nutrient. Both high and low intakes have been associated with thyroid cancer incidence. Development of dietary iodine monitors is needed to supplement the use of dietary recall methods which have not been well validated for iodine. In this study, 30 pooled urine samples, from ethnic groups on various islands in the South Pacific, were analyzed for iodine using epithermal instrumental neutron activation analysis (EINAA).
Authors:A. Türler, H. Gäggeler, K. Gregorich, H. Barth, W. Brüchle, K. Czerwinski, M. Gober, N. Hannink, R. Henderson, D. Hoffman, D. Jost, C. Kacher, B. Kadkhodayan, J. Kovacs, J. Kratz, S. Kreek, D. Lee, J. Leyba, M. Nurmia, M. Schädel, U. Scherer, Schimpf, D. Vermeulen, A. Weber, H. Zimmermann, and I. Zvara
On-line isothermal gas phase chromatography was used to study halides of261104 (T1/2=65 s) and262,263105 (T1/2=34 s and 27 s) produced an atom-at-a time via the reactions248Cm(18O, 5n) and249Bk(18O, 5n, 4n), respectively. Using HBr and HCl gas as halogenating agents, we were able to produce volatile bromides and chlorides of the above mentioned elements and study their behavior compared to their lighter homologs in Groups 4 or 5 of the periodic table. Element 104 formed more volatile bromide than its homolog Hf. In contrast, element 105 bromides were found to be less volatile than the bromides of the group 5 elements Nb and Ta. Both 104 and Hf chlorides were observed to be more volatile than their respective bromides.