September 2006

Potential for rock polishing enterprises in Southwestern Nigeria

Various igneous and metamorphic rocks constitute the basement complex especially much of southwestern Nigeria. They are composed of different proportion of felsic to mafic constitutions. Textural characteristics are also wide ranging. Based on petrographic and physical parameters, the majority holds good promise to be utilized for polished items. However, industrial exploitation may be constrained by a number of...

Author(s): Aigbedion I.

September 2006

Blended cement and lightweight concrete using scoria: Mix design, strength, durability and heat insulation characteristics

This paper reports the results of an investigation on the potential industrial utilization of volcanic scoria. The scoria is assessed for its utilization as a cement additive.  Pozzolanic activity of ground scoria is tested according to the Italian standards and found to be acceptable. X-Ray Diffraction (XRD) analysis and Differential Scanning Calorimetry (DSC) are conducted on finely ground scoria based...

Author(s): Khandaker  M. Anwar  Hossain

September 2006

Energy- angular correlation of medium energy particles produced in heavy Ion collisions

The information carried by the medium energy nucleons (gray particles) emitted in heavy ion collisions is studied. A canonical thermo dynamical model is proposed to deal with the interacting nuclei as nucleon gas system. The predictions of the model are compared with a complete set of measured data for the reactions of proton, helium, carbon and neon nuclei with the nuclear emulsion at 4.2 A GeV. It is found that the...

Author(s): N.M. Hassan, N.M. Sadek, Jamila Elsweedy and M.T. Hussein

September 2006

Biosorption of lead ions from aqueous solution by maize leaf

The removal of lead ions from dilute aqueous solution using maize (Zea mays) leaf as the adsorbent is reported in this paper. The effects of pH, initial metal ion concentration and contact time were studied at 27ºC. The analysis of residual Pb(II) ions was determined using atomic absorption spectrophotometer. Maximum adsorption occurred at pH 3. The adsorption isotherms obtained at 27ºC and optimum pH fitted...

Author(s): N. A. Adesola  Babarinde, J. Oyebamiji.Babalola and R. Adebowale Sanni

September 2006

Cyclic oxidation behavior of Ni- and Fe-based superalloys in air and Na2SO4-25%NaCl molten salt environment at 800 oC

The present investigation aims to evaluate the high-temperature oxidation and hot corrosion behaviour of Ni-based superalloy (Superni 75) and Fe-based superalloy (Superfer 800H). The superalloy specimens were exposed to air and molten salt (Na2SO4-25%NaCl) environment at 800 °C under cyclic conditions. The thermogravimetric technique was used to establish the kinetics of corrosion. X-ray diffraction (XRD), scanning...

Author(s): T.S. Sidhu, Ajay Malik, S. Prakash, R.D. Agrawal

September 2006

Non-Fitted Prediction of Clay Soil Aggregate Shrinkage

All available models of soil shrinkage curves, despite their essential differences, are based on fitting the model parameters. We try to construct a model that enables one to predict the shrinkage curve based on physical parameters, that is, parameters that can be measured or calculated without fitting, independently of an experimental shrinkage curve. Such a model is constructed for real aggregates of clay soils (i.e.,...

Author(s): V.Y. Chertkov