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Three samples of ZnO doped with CuO as additive were prepared by solid state reaction from the calcined oxides and characterized by SEM, EDX, and AFM. The results revealed the presence of intergranular phase. Additives found to be between ZnO grains. The conductivity of the three samples was measured with the frequency up to 100 KHz by LCR circuit. The calculated coefficients of nonlinearity and the conductivity are shown to be highly dependent on the frequency, concentration of copper oxide, surface morphology, and microstructure of the varistor samples. The temperature dependence of the conductivity of these samples will be studied in the future work.

LTE is a 3GPP evolution of UMTS that is envisaged to

The satellites laser ranging from Helwan SLR station during the last 20 years are discussed. The internal calibration method used at the Helwan SLR station is explained. The root mean square value of the calibrations carried out during the period from 1991 to 2008 is computed. To clarify the difference in the accuracy of the measurements, the results of the analysis of the data taken for all the satellites after the upgrading (2000) are given and compared with those of the satellites observed before the upgrading (1996). The total number of passes of the satellite observed during the period from 1991 to 2008 is presented and the results are compared with the other SLR stations.

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