We present the degradation mechanism of underground power lines. We prenet an original method, which, through the corrosion control of metallic sheats of cables assures the substantial increase, the explotation safety of underground power lines.

This paper presents the obtained results following implementation, on some underground medium voltage power lines from Cluj city - Romania, of an original protection system, which assures as well the anticorrosive protection of metallic screen sheets as the increase of the exploitation cables’ insulation resistance by “inverted electrochemical treeing” of ionic charge carriers from within insulator’s volume toward its screen.

The degradation process of metallic shields of underground power lines is an important factor upon theirs maintenance, reliability and safe operation. Therefore, the paper presents theoretical aspects concerning the electric phenomena taking place in cables' insulator / dielectric, the kinetics of corrosion reactions of metallic sheaths and original technical solutions for control of corrosion and increase of insulating resistance of underground

We have studied the electrical properties of some SnO2 samples obtained through sinterization at different temperatures, with and without CuO and Cu2O

We are presenting the results of investigations on some semi conducting SnO2 samples obtained through sinterization. We have determined the electrical rezistivity of these samples, in different humidity environments. It resulted that sinterized SnO2 can be utilized as resistant humidity sensor, the response time is determined firstly by the volume of the active material (SnO2).

We are presenting the results of electrochemical determinations through the method of steady state polarization curves regarding the electrochemical behaviour of some titanium electrodes in diverse concentrated NaCl solutions.

We are presenting the results of our research regarding the electrical rezistivity and the electrochemical behaviour of some electrodes obtained through sinterization of SnO2 with CuO and Cu2O

We are presenting the results of experiments regarding the quality of electroless Ni layer, deposed on single crystalline silicon samples, double doped by thermal diffusion with B and P.

We have studied the tehnical possibilities of controlling accelerated corrosion of underground pipelines interferred by a.c. stray currents. We are presenting an original method for control of a.c. stray currents corrosion, method that simultaneously assures the electrical safety of pipelines.

We present the results of fizical characterization of several semiconducting SnO2 samples, obtained through sinterization with and without CuO and Cu2O dopation.