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The present investigation, deals with the study of both hydrated Sulfate Resisting Portland Cement (SRPC) and fly ash (fly ash 20%, 30% and 50%) composite with two different waters. Among the three percentages of fly ash addition, 30% addition is found to be optimum. The samples (SRPC and 30% fly ash) were analyzed using the Fourier Transform Infrared Spectroscopy (FTIR) spectra. The relationship between compressive strength and molecular vibration changes were discussed using FTIR spectra. Also, the setting time is identified with the FTIR spectra and proper explanation with available literature for the kinetics is presented. It is inferred that increasing the fly ash concentration reduce the setting time. This is due to the calcium sulfoaluminate (CSA) present in the fly ash. Result of this study indicates that the blended paste better perform than the control paste hydrated with distilled water and effluent water.

The dielectric constant (ε') of Sulfate Resisting Portland Cement (SRPC) blended with 30% of fly ash by addition is measured using microwave bench at 9.54 GHz, for initial 30 hours of hydration. The heat of hydration for the same blend using heat of solution calorimetry is also measured. It is observed that contrary to the usual trend of retarding of fly ashes, it shows an accelerating trend with increasing strength as times passes. SEM micrographs and XRD patterns are also recorded and observed that C 4 Al 2 SO 16 (C 4 A 3 S¯) is found to be responsible for the accelerating trend of the mix. The hydration process in the early period is studied and it is suggested that suitable retarder should be adopted for the effective utilization.Cement chemistry notations: C=CaO, A=Al

The design and development of a novel route for the preparation of efficient photocatalysts for the treatment of polluted water is an essential need. Due to rapid expansion of pharmaceutical and textile industries, the discharge of drugs and sewage contaminants leads to water contamination. To address these issues, hydrothermally synthesized Ni−Cd−S/rGO nanocomposite with a cauliflower structure was developed. The prepared nanocomposite was studied using advanced characterization techniques to confirm crystal structure, surface morphology, optical studies and material composition in detail. Further, the photodegradation process of textile-based Methylene Blue (MB) and Methyl Orange (MO) dyes using Ni−Cd−S/rGO nanocomposite with desired time interval under natural sunlight was also investigated. The maximum photocatalytic performance of > 90% was achieved for the photocatalyst. The photodegradation rate can be maintained after 5 recycling tests in the presence of MB and MO dyes. The remarkable degradation efficiency, high rate constant and reusability of the Ni−Cd−S/rGO nanocomposite make it an excellent choice for textile effluent treatment.