The residual stresses and the molecular direction through a product provide the important information on how that product will behave. This is an important preoccupation in the production of plastics by the uses such as information storage. In this work a method of optional non-destructiva testing of evaluation of the quality of compact discs was evaluated and a quantitative analysis became of the state of different tension of CD's.

It is known the YBa2Cu30H (Yl23) prepared by the solid reaction method coexists with a green phase Y2BaCu05 (Y211). In this work we study the behavior of the Y211 (pure) overheated at 11 00°C and 1300°C respectively. The starting sample was prepared by the conventional solid reaction method using appropriate amounts of Y203, BaC03 and CuO; the initial sample was green in color. From the X ray diffractogram (XRD) and using the Rietveld refinement we found that the crystalline structure is orthorhombic and belong to the Pnma spatial group. This is the sorne structure as the one found by Michael and Raveau 1 • The starting sample was overheated at 11 00°C under oxygen pressure of 0.1 atm. According with the XRD, there are no significant variations on its structure. Nevertheless after an overheating of 1300°C in the same oxygen pressure, a new phase Y203 with a cubic symmetry together ...

The residual stresses and the molecular direction through a product provide the important information on how that product will behave. This is an important preoccupation in the production of plastics by the uses such as information storage. In this work a method of optional non-destructiva testing of evaluation of the quality of compact discs was evaluated and a quantitative analysis became of the state of different tension of CD's.

In this work the sensibility behavior of a coaxial GeHP detector is presented with respect to the arrival of a colhmated radiation beam in the frontal and lateral sides ofthe detector. The results show that for a horizontal or vertical configuration of the cryostat, a preferential direction of the detection exists. From the sensibility profiles, an estimate of the sensitive dimension of the semiconductor glass of the detector was obtained.

A measuring system of nuclear parameters using the techniques of In verse Kinetics and Neutron Noise has been installed in the Peruvian Nuclear Resean:h Reactor RNl. In this papera brief description of the system components is presented as well as of its ínstallatlon in the reactor core. The resu1ts of the measurements of reactor power and reactivity are reported.

In this work it is presented the use of one solid state nuclear track detector, CR-39, for the determination of thermal neutron flux distribution from neutron sources, by means ofthe (n,p) nuclear reaction. Measurements of the thermal flux from an Am-Be neutron source with polyethylene and paraffin moderators were chemically etched in NaOH 6,25 N at 71 'C during 6 hours. An optical microscope 160X was used to observe the etched tracks. The flux profiles were obtained. 1t was found that polyethylene is a better moderator than paraffin for this neutron source.