Search Results

You are looking at 1 - 3 of 3 items for

  • Author or Editor: F. Carrasco x
Clear All Modify Search

Abstract  

Lyocell, modal and viscose fibers were subjected to mercerization or to solar degradation. The ulterior thermal degradation was analyzed by means of differential scanning calorimetry (DSC). Thermal analysis shows wide exothermic processes that began between 250 and 300C corresponding to the main thermal degradation and are associated to a depolymerization and decomposition of the regenerated cellulose. Thermal degradation was analyzed as a function of concentration and time. Lyocell fiber is the most stable under thermal degradation conditions. Furthermore, mercerized samples are initially more degraded and present a lower thermal stability.

Restricted access

Abstract  

A crystallization kinetics analysis of several polypropylene-polyethylene (PP-PE), PP-rich copolymers was made by means of differential scanning calorimetry. The crystallization was studied via calorimetric measurements at different cooling rates. Several additives were added to the base material. Some test samples were subjected to artificial ageing processes. A modified isoconversional method was used to describe the crystallization process under non-isothermal conditions. The value of the Avrami parameter was determined for primary and secondary crystallization.

Restricted access
Journal of Radioanalytical and Nuclear Chemistry
Authors: L. Reyes-Herrera, G. Ferro-Flores, J. Lezama-Carrasco, M. Gonzalez-Zavala, F. Ureña-Nuñez and E. Avila-Ramirez

Abstract  

An alkaline kit formulation (pH 9) to obtain [99mTc]MAG3 with radiochemical puritives over 98% has been developed, avoiding the addition of filtered air to the vial, the use of large amounts of99mTc activity (i.e., 3.7 GBq) or the reconstitution of large volumes. The use of this radiopharmaceutical in mice showed a minimal accumulation in the hepatobiliary system (0.37±0.3% I.D., 1 h postinjection). However, in rabbits we always obtained good image quality.

Restricted access