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This paper presents an experimental investigation on the durability properties of metakaolin (MK) and bottom ash (BA) blended geopolymer under different environmental exposure. The blended geopolymer concrete (GPC) was prepared with sodium based alkaline activators under ambient curing temperature. The concentration of sodium hydroxide used was 8 M. The ratio of sodium silicate to sodium hydroxide was kept as 2.0. The performance of blended geopolymer concrete was compared with conventional concrete (CC). The test results reveal that blended geopolymer concrete develops a better performance against sulphate and acid resistance. Also, MK-BA GPC shows enhanced performance over the conventional concrete in terms of sorptivity, rapid chloride and water absorption.

Polymer nanocomposites which possess outstanding antimicrobial efficacies are potential materials for food packaging applications. Amidst the several biodegradable synthetic polymers, Polyvinyl alcohol exhibits excellent biocompatibility and are very economical. A new hybrid composite based on Polyvinyl alcohol with GO and reduced rGO with Potassium Chloride as salt spacer was synthesized using solvent cast method. The antibacterial activity of the prepared films was explored against Pseudomonas aeruginosa (ATCC 7903) Escherichia coli (ATCC 8739) Campylobacter jejuni (ATCC 29428) Staphylococcus aureus (ATCC 6538). The antifungal activity was studied against Candida albicans (ATCC 10231) Trichodermaharzianum (ATCC 90237) Aspergillus Niger (ATCC 6275). Polymer nanocomposite with GO as dispersant (4 wt%) have shown inhibitory activity with respect to P. aeruginosa, E. coli and C. jejuni. Polymer nanocomposite with rGO as dispersant (4 wt%) have inhibitory activity against E. coli, C. albicans and against P. aeruginosa using well diffusion method.

The main objective of this study was to investigate the flexural behavior of self compacting self curing concrete (SCSCC) beams using lightweight expanded clay aggregates (LECA) and fly ash aggregates (FAA). The light weight aggregates used in this experimental investigation are high porous and water absorption capacity; so that the water required for self curing is taken from the water which is held in the internal pores of the aggregates. Self curing by the addition of lightweight fine aggregate under saturated surface dry (SSD) condition enhances the strength & durability of the concrete and it maintains saturated condition with in the hydrating cement paste. The fine aggregate was replaced by LECA/FAA by 0% to 20% at 5% interval in volume basis. The flexural behavior of self compacting self curing concrete in hardened state was carried to assess the feasibility of the study. The reinforced concrete beams of effective size 1200 mm x120 mm x180 mm and reinforced with High Yield Strength Deformed (HYSD) bars are casted and tests were performed in loading frame. The load deflection behavior, moment carrying capacity and ductility ratio of beams are found and the test results indicate that the 15% replacement of fine aggregate by LECA/FAA achieved higher moment carrying capacity and ductility ratio.

An attempt has been made in the present work to study the effect of type of coarse aggregate on the strength properties and fracture energy of M30, M50 and M80 grade of concretes. The aggregate used in this study includes Grey Granite (GG), Anorthosite (AS) Charnockite (CK) Limestone, (LS) and Gneiss (GS). The result shows that the strength of concrete is greatly influenced by the aggregate types in high strength concrete. However, the aggregate has not impacted the Normal Strength Concrete as the strength is governed by the characteristics of interfacial transition zone, rather than aggregate. Among all aggregates, the Grey Granite aggregate has produced concrete with highest compressive strength followed by Anorthosite, Charnockite, Limestone and Gneiss indicating that the surface texture, structure and mineralogical composition played a dominant role. The similar trend was noticed even in fracture energy and modulus of elasticity of high strength concrete.

This work intends to investigate the superior properties of Pyrrolidine-2-carboxylic acid Cadmium Chloride Hydrate (PCCH) that was grown by the slow evaporation technique at room temperature. The crystalline nature of PCCH was found by powder X-ray diffraction analysis. The optical behaviour of the grown crystal was unveiled by using UV-vis-NIR. The refractive index of the crystal was measured experimentally using Metricon prism coupler for the first time. The z-scan measurement was taken to explore the third harmonic generation efficiency of the grown crystal for the first time. The structural imperfections were analyzed by performing the etching studies on the grown crystal. The first attempt of antibacterial activity of this crystal was carried at different concentrations (25, 50, 75 and 100 μg/mL) in-vitro against Staphylococcus epidermis (G + Ve); Escherichia coli, Vibrio cholera (G–Ve) bacteria. These studies established that PCCH crystals might find useful applications in the field of biomedical and nonlinear optics.

Semi-organic nonlinear optical crystal Calcium5-Sulfosalicylate (CA5SS) was grown by slow evaporation solution growth technique. The cell parameters and molecular structure of the grown crystal were studied by single crystal x-ray diffraction analysis. The presence of various functional groups of the grown crystal was confirmed using Fourier transform infrared (FT-IR), Fourier transform Raman (FT-Raman) analysis. UV–Visible spectrum shows that CA5SS crystals have high transmittance in the range of 330–900 nm. The refractive index, birefringence and transient photoluminescence properties of the grown crystal were analyzed. The frequency doubling of the grown crystal (CA5SS) were studied and compared with that of KDP.

Pervious concrete can be described as a porous concrete which permits the penetration of water through the interconnected network of pores. In general, pervious concrete is produced using Ordinary Portland Cement (OPC) as binder, and being used for pedestrian path, parking lots and has many other applications. In this paper Fly ash-Lime-Gypsum (FaL-G) binder has been used as a binder and studies have been carried out for physical, mechanical and other relevant properties with various sizes of coarse aggregates. The results are compared with the pervious concrete made out of OPC binder. The test results are presented and discussed elaborately. It is found that FaL-G binder pervious concrete satisfies the requirements laid down by codal provisions.

A novel third-nonlinear optical (NLO) crystal, piperazine-1,4-diium bis(2,4-dichlorobenzoate) (abbreviated as PBDCB) was successfully synthesized and grown good quality crystal by slow evaporation solution growth technique by methanol as a solvent at room temperature. The formation of the grown crystal was carried out by single-crystal X-ray diffraction analysis. The analysis of a single crystal X-ray diffraction reveals that the title compound was crystallized in the monoclinic system with centrosymmetric space group P21/c and thereof lattice parameter are a = 11.166(6) A, b = 8.160(5) A, c = 12.085(6) A, β= 113.18(3)°, Z = 4. Crystallographic studies also reveal that the molecules are linked via N—H···O and C—H···Cl hydrogen bonds. Pairs of intermolecular N—H···O hydrogen bonds generate R44(12) ring motifs. The powder X-ray diffraction study was completed and the peaks were indexed. UV–Vis spectral studies were revealed that the grown crystal is transparent in the entire visible region with a lower cut off the wavelength of 286 nm. The optical band gap of the title compound was measured by Tauc's plot method, and it was obtained to be 3.9 eV, which shows suitable applications of the optoelectronic device. In the photoluminescence study, the grown crystal was revealed violet emission radiation, and thereof peak has appeared at 312 nm. The functional groups of the grown crystal have been determined by Fourier Transform Infra-Red (FTIR) spectroscopy technique. In thermogravimetric (TGA) and differential thermal analysis (DTA) analysis, the title material was determined as thermally as stable up to 163 °C. The Vickers Microhardness test ascertained the mechanical properties of the grown crystal material, and it belongs to a soft material category. The dielectric measurements of the developed crystal material were also ascertained at various frequencies. The dielectric constant, dielectric loss, and A.C. the conductivity of title material was studied with different frequencies and temperatures. The laser damage threshold (LDT) of the grown crystal was then calculated by using Nd: YAG laser. The grown crystal has given the measured (LDT) value of 8.97 GW/cm2. The third-order nonlinear optical (NLO) properties characteristics, such as absorption coefficient (β ~ 0.02 × 10−4 cm/W), the refractive index (n2 ~ 4.06 × 10−8 cm2/W), and their susceptibility range values of (χ(3) ~ 2.17 × 10−6esu) of the grown crystal was estimated by Z-scan technique, suggests that the grown crystal material PBDCB was served as a promising source for nonlinear optical devices.

Metal-organic Zinc (Tris) Thiourea Chloride (ZTTC) crystal was grown from aqueous solution by slow evaporation technique. The unit cell parameters and the crystalline nature were revealed from the X-ray diffraction studies. The presence of various functional groups was confirmed by FTIR analysis. The optical behavior of the grown crystal was examined by UV–vis-NIR, NLO and fluorescence studies. The thermal properties of the crystal have been investigated by thermo-gravimetric analysis and differential thermal analysis (TGA/DSC). Dielectric studies for various frequencies and temperature were carried out to the as grown crystal. The mechanical strength of the crystal was studied using Vickers microhardness tester. The structural imperfection of the grown crystal was examined by etching studies. The antibacterial activity was carried out at different concentrations (25–100 µg/mL) in-vitro against Bacillus subtilis (G+Ve); Pseudomonas aeruginosa, Salmonella typhi, Shigella flexneri (G-Ve). Moreover, the prepared ZTTC crystal will be applicable electro-optic device and pharmaceutical applications.

This work investigates the various properties of (Hexakis) Thiocarbamide Nickel (II) Nitrate (HTNN) single crystal grown by slow evaporation of mixed ethanol and deionized water solvent at room temperature. The cell parameters and the crystalline nature of the grown crystal were revealed by X-ray diffraction studies. The antibacterial activity of the HTNN crystal was studied in-vitro against gram +ve species (Bacillus subtilis, Staphylococcus aureus) and gram –ve species (Escherichia coli, Aeromonas spp and Pseudomonas aeruginosa) with different concentrations ranging from 25 to 100 µg/mL. The grown crystal was subjected to FTIR and UV–vis-NIR studies to identify its various functional groups and optical behaviour. The dielectric studies were performed with the grown crystal for different frequencies and temperature. The melting point and different stages of decomposition of the HTNN crystal were confirmed by using the thermal analysis. The growth mechanism and mechanical strength of the crystal were found from etching and microhardness studies.