| Abstract: |
ABSTRACTSuperplasticizers are widely used in the production of concrete with excellent workability giving high performance, high strength and improve the durability. Superplasticizers improve the dispersion of dispersing cement particles in paste. There are too mThis investigation aimed to study the effect of delaying addition of some prepared organic superplasticizers after 5.0, 7.5, 10.0, 12.5 and 15.0 minutes on the properties of cement pastes containing condensed silica fume. These superplasticizers were prepThe investigation of the hydration characteristic of cement pastes assessed by the determination of the water of consistency, initial and final setting times, rheological properties, combined water and free lime contents, total porosity, bulk density and The electron temperatures for both Ar and He discharge were determined in this study by four ways: (1) the semi-log plot method applied to the I-V characteristic curve of the single probe, (2) by multiplying the average electron energy, , derived from theThe axial and radial distributions of plasma density under various discharge conditions for both Ar and He were also investigated. The electron density has been obtained by three methods: (1) by using the single probe, determining the value of electron cuThe electron energy distribution functions, EEDFs, for both Ar and He were determined at different discharge conditions by applying the double differentiation method to the single probe characteristic curves. The EEDFs were measured and distributed along The effects of discharge conditions, especially, discharge voltage and pressure on the determined plasma parameters namely, electron temperature, electron density, ion density, and EEDFs, were also under the scope of our study.
|
|
|