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Presently, there is an increased emphasis on the use of blended cement like slag cement, fly ash cement etc. This reduces the energy requirement for cement production or reduces the CO2 release in the environment as the portland cement clinker is produced utilizing calcium carbonate based raw material. The replacement of calcium carbonate by alternative raw material like slag may again reduce the energy consumption. In the present investigation, blast furnace slag has been utilized as a cement raw material for the production of portland cement clinker. Clinker thus produced has been characterized to see the effect of slag utilization. A normal portland cement clinker has also been prepared to compare the properties. The clinkerisation process was quicker in case of slag containing raw mix. The free lime content of that clinker was also low compared to normal clinker. The amount of C3S phase formation was higher in slag containing clinker. Similarly, the hydration rate and compressive strength of cement produced utilizing slag clinker was higher compared to normal portland cement. All these results indicate that slag could be utilize to reduce the calcium carbonate content of cement raw mix efficiently to produce better, cheap and environmental friendly cement.

The aim of the present work is to find the applicability of thermal tempering method for healing of the glass surface crack. The crack in the glass surface has been generated by Vicker’s Hardness Instrument with 1KgF load and dwell time of 10 sec. It is that the healing of the crack may be due to the viscous flow at the glass surface at the temperature greater than glass transition temperature. The driving force for this healing may be the surface roughness around the crack. All the samples were heat treated at 650°C and 700°C with a heat treatment time 2 hours, 4 hours and 6 hours. After the heat treatment for a specific temp and time, all the samples were rapidly quenched so that a surface compressive stress can be as we have experienced in thermal temp process. After rapid quenching, it has been observed that with an increase in dwelling time of the heat treatment the crack length decreases significantly. It has also been found that rapidly quenched glass not only closes the crack but also been observed a significant increase in surface compressive stress and flexural strength.

Lithium AluminoSilicate (LAS) Glass ceramic (GC) finds use in kitchenware, cooktop panels and telescope mirror because of its characteristic of very low and sometime zero thermal expansion coefficient (TEC) in the application temperature range. In this project work, conventional melt-quenching technique has been used for the development of the LAS base glass. After controlled crystallization, LAS GC has been developed using titania and/ zirconia as a nucleating agent and their effect has been studied in the presence of yittria. Here the yittria content has been varied from 1-3 wt% with corresponding variation in titania (2-4 wt%) or zirconia (2-4 wt%). Effects of temperature and time on crystallization have also been studied followed by the effect of crystallization on thermal expansion co-efficient of the developed glass ceramics. Developed crystalline phases were â-Spodumene and â-quartz solid solution (ss) which has been authenticated by X-ray diffractometer. TEC of the GC has been measured and studied using Dilatometer in the temperature range of 25oC to 750oC and its surface hardness has been measured at 0.5Kgf using Vickers indentation method.

(Ba0.2Sr0.8)TiO3-B2O3-K2O based glass as well as glass ceramic with and without 0.1 mol % Nb2O5 were developed by the conventional melt quench method. XRD and FTIR spectra of the glass samples confirms the formation of amorphous structure and presence of stretching and deformation vibrations of B-O-Si linkage and Si-O-Si bridges, respectively. Differential scanning calorimetry (DSC) of the glass sample reveals that addition of 0.1 mol % Nb2O5 elevates the onset of crystallization temperature from ~600°C to ~675°C. XRD reveals that desired SrBaTiO3 phase was formed upon controlled crystallization of the glass samples at ~750-780°C for 3h. SEM-EDS analysis of the un-doped glass ceramic sample shows the formation of micron sized flower-like, and needle shaped crystals. However addition of 0.1 mol % Nb2O5 modifies the microstructure to irregular shaped crystals. Results from the dielectric measurements suggest that upon addition of 0.1 mol % Nb2O5 the dielectric constant remains the same as compared to the un-doped sample

(Ba0.3Sr0.7)TiO3-2SiO2-B2O3-K2O based borosilicate glass with and without 0.1 mol % La2O3 was successfully developed by melt-quench method. XRD and FTIR spectra of the glass sample confirms the formation of amorphous structure and presence of stretching and deformation vibrations of B-O-Si linkage and Si–O–Si bridges, respectively. Differential scanning calorimetry (DSC) of glass samples reveals that addition of 0.1 mol % La2O3 elevates the onset of crystallization temperature from ~600°C to ~670°C. Controlled crystallization of the glasses ~750-780°C for 3h leads to the formation of desired perovskite SrBaTiO3 glass-ceramics. SEM-EDS analysis of the undoped glass-ceramic sample shows the formation of micron sized flower-like and needle shaped crystals. However, addition of 0.1 mol % La2O3 modify the crystal structure to blocky precipitates. Results from dielectric measurements suggest that space charge polarization mechanism is likely responsible for the large observed dielectric constant (~700) of the 0.1 mol % La2O3 doped glass ceramics sample at low frequencies.

[(BaZr0.1Ti0.9O3]-[2SiO2-B2O3]-[K2O] based borosilicate glass with and without 0.1 mol % La2O3 was successfully developed by melt-quench method. XRD and FTIR spectra of the glass sample shows broad peaks ~24-35° (2? value) which is due to the formation of amorphous borosilicate phase and presence of stretching and deformation vibrations of B-O-Si linkage and Si–O–Si bridges, respectively. Differential scanning calorimetry (DSC) of glass samples reveals that addition of 0.1 mol % La2O3 elevates the onset of crystallization temperature from ~560°C to ~628°C. Controlled crystallization of the glasses at 800°C for 3h leads to the formation of fresonite (Ba2TiSi2O8) phase. SEM-EDS analysis of the un-doped glass-ceramic sample shows the formation of micron sized L-shaped and needle shaped crystals. However, addition of 0.1 mol % La2O3 modify the L-shaped crystal structure to blocky globular crystals. Dielectric measurements shows that addition of 0.1 mol % La2O3 increases the dielectric constant from ~45 to ~125.

Alumina adsorbent has wide acceptance for mitigation of excess fluoride ions from water. The challenging part is preparing this adsorbent in the granule shape with high porosity and PZC value, ensuring its applicability under normal pH of water, i.e., 6.5 to 7.5, and easy separation after use. This research has attempted to prepare highly porous alumina adsorbents in granule form using low-cost ceramic raw material kaolin. The study aims to find a suitable, environment-friendly, and highly effective alumina adsorbent for defluoridation. The adsorbents are prepared both in bead shape and granule shape through oil drop method using aluminium rich leachate extracted from kaolin. Al3+ leachate is obtained by thermal treatment followed by acid leaching of kaolin. Incorporating pore former in the bead-shaped adsorbent (prepared directly using concentrated acid leachate) is challenging, so two sols, namely sol-1 and sol-2, are prepared from Al3+ leachate with and without impurity removal. The sols are mixed with different pore-formers like PEG, PVP, spent tea leave waste (STLW), starch, sucrose individually, and PVA binder to convert into a semi-gel state. This semi gel is then injected into a column containing paraffin oil as an upper layer and ammonia as a bottom layer with the help of a syringe pump to form porous alumina adsorbents. All the prepared adsorbents, both bead-shaped and granule, are washed, dried, and calcined at different temperatures to get the desired alumina phase. Different characterization techniques like XRD, FTIR, FESEM, and BET surface area analysis are employed to get preliminary information about the applicability of the prepared adsorbent for the fluoride adsorption study. A batch adsorption study is then carried out systematically using each type of prepared alumina adsorbents. The adsorbent dose and kinetics parameters are thoroughly studied to achieve the maximum fluoride removal in the fluoride contaminated aqueous system. Bead-shaped adsorb