September 2012

Geomagnetic field variations at dip equatorial latitudes of West Africa

  A comprehensive study of geomagnetic field variations has been carried out at the dip equatorial latitudes of West Africa. The data obtained during the 1993 French participation in the International Equatorial Electrojet Year experiment in Africa was used for the analysis. Only the quiet condition was examined. Variation in the three geomagnetic field elements (H, D, and Z) showed more variability in D...

Author(s): T. N. Obiekezie

September 2012

Calculation of two-center overlap integrals over slater-type orbitals via fourier transform convolution theorem

  Formulas for two-center overlap integrals over slater type orbitals are presented. The established formula contains Gaunt coefficients and auxiliary functions. Analytical and recurrence relations for these auxiliary functions have been presented. The efficiency of the presented algorithm for the evaluation of two-center overlap integrals depends strictly on the accurate calculation of these auxiliary...

Author(s): Telhat OZDOGAN and Ayse NALCACI

September 2012

Statistical evaluation of hardness behavior in a thermally aged A356.0-type Al-Si-Mg alloy

  A statistical study has been made on the isothermal treatments of A356.0-type Al-Si-Mg alloy. The reprocessed alloy was subjected to hardness evaluation. The values obtained were processed using statistical package for social scientists (SPSS) software to compare all tempers and multiple-step thermal ageing treatment (MSTAT) values by analysis of variance (ANOVA) and Pearson Correlation Index. Equally, a...

Author(s): Abdulwahab M., Popoola, A. P. I.  and Kikawa, C. R.