In recent years, the need for low energy materials has become increasingly important. With government targets aiming to reduce carbon emissions by 80% by 2050, and the construction industry being responsible for 50% o...In recent years, the need for low energy materials has become increasingly important. With government targets aiming to reduce carbon emissions by 80% by 2050, and the construction industry being responsible for 50% of the UK's carbon emissions, it is of vital importance that positive changes are made. One of these changes is to reduce the carbon footprint of the materials used in construction. Lime mortar has been used for centuries, but since the arrival of cement, its use in modern construction has diminished, in part due to having lower compressive strengths than cement mortar. Air lime mortar, in particular, can be categorised as low energy due to the reabsorption of a significant amount of COE during the setting process: carbonation. The current study focuses on the impact of different types of aggregate (limestone and silicate) on air lime mortar strength. Previous research has found that higher strengths can be achieved with the use of limestone aggregate, but little is known about the reasons why. The research presented here looks at a microstructural analysis through use of SEM (scanning electron microscopy) in order to determine reasons behind the strength differences. At early stages of curing, there are clear differences at the interface of binder and aggregate.展开更多
The aggregation behavior of submicron-sized particles of praseodymium-doped zirconium silicate, a ceramic pigment, in aqueous suspension was predicted by a modified population balance model, In the model, the collisio...The aggregation behavior of submicron-sized particles of praseodymium-doped zirconium silicate, a ceramic pigment, in aqueous suspension was predicted by a modified population balance model, In the model, the collision frequencies were selected to describe evolution of the particle size distribution of the suspension. The collision efficiency was estimated as a function of interaction potential between particles based on Derjaguin-Landau-Verwey-Overbeek theory. The population balance model was modified to predict the stable state of the aggregation by introducing the volume mean size of aggregate to stability ratio. In addition, aggregation of the particles in aqueous suspension in the presence of sodium dodecyl benzene sulfonate or potassium chloride was experimentally investigated. The predicted data (i.e., the final aggregate size, aggregation rate, and particle size distribution) were similar to the experimentalresults.展开更多
文摘In recent years, the need for low energy materials has become increasingly important. With government targets aiming to reduce carbon emissions by 80% by 2050, and the construction industry being responsible for 50% of the UK's carbon emissions, it is of vital importance that positive changes are made. One of these changes is to reduce the carbon footprint of the materials used in construction. Lime mortar has been used for centuries, but since the arrival of cement, its use in modern construction has diminished, in part due to having lower compressive strengths than cement mortar. Air lime mortar, in particular, can be categorised as low energy due to the reabsorption of a significant amount of COE during the setting process: carbonation. The current study focuses on the impact of different types of aggregate (limestone and silicate) on air lime mortar strength. Previous research has found that higher strengths can be achieved with the use of limestone aggregate, but little is known about the reasons why. The research presented here looks at a microstructural analysis through use of SEM (scanning electron microscopy) in order to determine reasons behind the strength differences. At early stages of curing, there are clear differences at the interface of binder and aggregate.
文摘The aggregation behavior of submicron-sized particles of praseodymium-doped zirconium silicate, a ceramic pigment, in aqueous suspension was predicted by a modified population balance model, In the model, the collision frequencies were selected to describe evolution of the particle size distribution of the suspension. The collision efficiency was estimated as a function of interaction potential between particles based on Derjaguin-Landau-Verwey-Overbeek theory. The population balance model was modified to predict the stable state of the aggregation by introducing the volume mean size of aggregate to stability ratio. In addition, aggregation of the particles in aqueous suspension in the presence of sodium dodecyl benzene sulfonate or potassium chloride was experimentally investigated. The predicted data (i.e., the final aggregate size, aggregation rate, and particle size distribution) were similar to the experimentalresults.