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Hydraulic Activity in Synthetic and Commercial Slags (open access)

Hydraulic Activity in Synthetic and Commercial Slags

Slag, by itself, shows very little hydraulic activity. However, hydration is greatly accelerated by incorporation of the slag with Portland cement. This phenomenon is due to the activating role of calcium hydroxide released from the hydration of Portland cement. This study was aimed at finding other activators that will increase hydration in both synthetic and commercial slags. The effects of chemical composition and the aggregation state of the slag on the hydration process were also investigated. For the synthetic slags, the aggregation state was altered by different quenching techniques. The chemical composition was varied by synthesizing a series of slags. The degree of hydration was studied by developing a thermogravimetric analysis technique and the glass content was determined using microscopy. Minerals were determined using powder x-ray diffraction analysis.
Date: May 1982
Creator: Saad, Bahruddin bin
System: The UNT Digital Library
Methods Development for Simultaneous Determination of Anions and Cations by Ion Chromatography (open access)

Methods Development for Simultaneous Determination of Anions and Cations by Ion Chromatography

The problem with which this research is concerned is the determination of inorganic anions and cations with single injection ion chromatography. Direct detection of the separated analyte ions occurs after the analyte ions have passed through ion-exchange resins where they are separated according to their affinity for the ion-exchange resin active sites. The techniques involve the use of essentially a non-suppressed ion chromatographic system followed by a suppressed ion chromatographic system. With this system it is possible to accomplish both qualitative and quantitative determinations.
Date: May 1987
Creator: Jones, Vonda K. (Vonda Kaye)
System: The UNT Digital Library
Analysis of PAH and PCB Emissions from the Combustion of dRDF and the Nondestructive Analysis of Stamp Adhesives (open access)

Analysis of PAH and PCB Emissions from the Combustion of dRDF and the Nondestructive Analysis of Stamp Adhesives

This work includes two unrelated areas of research. The first portion of this work involved combusting densified refuse derived fuel (dRDF) with coal and studying the effect that Ca(0H)2 binder had on reducing polycyclic aromatic hydrocarbon (PAH) and polychlorinated biphenyl (PCB) emissions. The second area of work was directed at developing nondestructive infrared techniques in order to aid in the analysis of postage stamp adhesives. With Americans generating 150-200 million tons a year of Municipal Solid Waste (MSW) and disposing of nearly ninety percent of it in landfills, it is easy to understand why American landfills are approaching capacity. One alternative to landfilling is to process the MSW into RDF. There are technical and environmental problems associated with RDF. This work provides some answers concerning the amount of PAH and PCB emissions generated via the combustion of RDF with coal. It was found that the Ca(OH)2 binder greatly reduced both the PAH and the PCB emissions. In fact, PAH emissions at the ten-percent level were reduced more by using the binder than by the pollution control equipment. If the Ca(0H)2 binder can reduce not only PAH and PCB emissions, but also other noxious emissions, such as acid gases or dioxin, …
Date: May 1989
Creator: Poslusny, Matthew
System: The UNT Digital Library