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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.

Low temperature solution combustion synthesized Cr3+(1- 4 mol%) doped Mg2SiO4 nanoparticles were analyzed by Powder X-ray Diffraction (PXRD), Fourier Transform Infra-Red (FTIR) spectroscopy, Cyclic voltammetry (CV) and Electrochemical Impedance Spectroscopy (EIS) techniques. PXRD profile shows the samples are crystalline.FTIR spectra show MgO6 octahedral and Si-O bending and stretching modes.It was observed that, CV show excellent semi rectangular shaped voltammograms due to the oxidation reduction reactions and the reversibility of the reaction which suits for electric double layer capacitance.Charge transfer resistance (Rct) was found to be 10 Ωindicates the better electron transfer from one phase to another.

This paper presents a study on the use of alkali-activated metakaolin (MK) and Bottom Ash (BA) blend in geopolymer concrete. A preliminary attempt was made on alkali-activated metakaolin and bottom ash-based geopolymer (MK–BA-GPM) mortar with river sand as fine aggregate to find a suitable mix to produce geopolymer concrete (GPC). The liquid alkaline activator is a combination of sodium silicate and sodium hydroxide solution. The molarity of NaOH was 8 M. Molar ratio of Na2O and SiO2 was 2, and ambient curing mode was selected. Also, M30 grade control concrete was made using OPC and cured in water. Further, GPC and control concrete specimens were tested for compressive strength, split tensile, flexural strength and modulus of elasticity. Also, XRD, SEM and EDAX studies were carried out to analyse element/mineral compounds present and the microstructure and morphological characteristics of GPC to substantiate the strength development. MK–BA GPC demonstrated 49% higher compressive strength than that of control concrete at 28 days. More so, the early as well as later strength gain of GPC was remarkably higher than that of OPC. Strength was due to densification of microstructure over a period of time and due to the formation of additional crystalline phases in geopolymer concrete.

V2O5 nanoparticles were prepared by ultrasound-assisted method and characterized using XRD, FTIR, SEM, and TEM. XRD pattern revealed an orthorhombic V2O5 phase with an average crystallite size of 5...

TiO2 nanoparticles were prepared by a microwave-assisted green method using Andrographis paniculata as fuel. XRD, Raman, FESEM with EDS, TEM and UV-DRS have been used for characterization of TiO2 nanoparticles. XRD exhibits a tetragonal structure with the average crystallite size of 19 nm. From Raman studies, the peaks at 196 (Eg), 395 (B1g), 514 (A1g) and 639 (Eg) are revealing the anatase phase of TiO2. FESEM and TEM images confirm the nanoparticles with average particle size are 25 nm. Optical bandgap of biogenic TiO2 nanoparticles is 3.27 eV. Photoluminescence spectrum of TiO2 nanoparticles showed blue and green emissions. The photocatalytic degradation study of biogenic TiO2 nanoparticles was investigated against the Rose Bengal (RB) dye under UV light irradiation. Microwave-assisted green synthesized TiO2 nanoparticles showed an excellent photocatalytic activity (RB dye). Antibacterial activity (disc diffusion method) of microwave-assisted biogenic TiO2 nanoparticles is studied against foodborne pathogens. TiO2 exhibits anti-lung cancer (human lung cancer A549: IC50: 24.96 µg/mL) activity along with biocompatibility.

This chapter consists of systematic synthesis of magnesium silicate nanoparticles by solution combustion method using ODH fuel. Compared to other fuels, ODH has the better advantages of obtaining crystalline nanomaterials without post calcinations. By doping different rare earth ions to magnesium silicate, the product can be used for luminescent applications. Synthesis of magnesium ferrite nanoparticle is done using molten salt method followed by the synthesis of polymer composite in the form of fibers by the process of electrospinning.

In the present work, NiO nanoparticles based on Andrographis paniculata (leaf extract) were prepared through the microwave-assisted method. The obtained nanoparticles were analyzed using XRD, FTIR,...

CdO–ZnO–MgO nanocomposite was synthesized by the microwave-assisted method and characterized by X-ray diffraction (XRD), FTIR, FESEM with energy dispersive X-ray spectrometry and TEM. XRD revealed the existence of the CdO (cubic)–ZnO (hexagonal)–MgO (cubic) structure with an average crystallite size of CdO (33 nm), ZnO (35 nm), MgO (30 nm) and also the dislocation density is evaluated. FTIR confirmed the presence of Cd–O, Zn–O and Mg–O by characteristic vibrational peaks at 863, 566 and 693 cm− 1. The surface morphological (FESEM and TEM) images appear the agglomerated rod-like structure. From the UV–Vis spectra, the bandgap is estimated as 2.67 eV. The prepared nanocomposite acts as an excellent photocatalyst for the removal of both dyes (Methylene blue and Congo red) under solar light irradiation. The antibacterial activity was carried out at different concentrations (25, 50, 75 and 100 µg/ml) in vitro against Escherichia coli, Pseudomonas aeruginosa, Vibrio cholera, Klebsiella pneumoniae, Proteus vulgaris, Salmonella typhi (G −ve); Bacillus subtilis (G +ve) bacteria. The zone of inhibition of 25 mm has a high antibacterial activity towards the gram-negative bacterium (P. vulgaris).

In this study, SnO2 has been synthesized using Andrographis Paniculata (A. Paniculata) by microwave-assisted method. It is also characterized by X-ray diffraction (XRD), scanning electron microscop...

Organic single crystal of l-histidinium l-tartrate hemihydrate was grown by slow solvent evaporation method using a cationic precursor (l-histidine), an anionic precursor (l-tartaric acid) and water as a solvent. The compound crystallizes in non-centrosymmetric space group, C2 of monoclinic structure. The nature of co-ordination and the vibrational assignments of the compound were confirmed by FTIR spectroscopy. Optical, fluorescence and NLO studies were performed on the grown crystal to reveal the optical behaviour. Thermal stability of the crystal was investigated using thermo gravimetric and differential thermal analysis (TG/DTA) and the kinetic parameters such as activation energy (E), enthalpy (ΔH), entropy (ΔS) and Gibb’s free energy of activation (ΔG) was obtained using Coats–Redfern relation. The grown crystal was subjected to dielectric studies for different frequency and temperature. The Vicker’s micro hardness test was carried away to test the mechanical stability and to detect the hardness parameters. The growth pattern of the grown crystal was analyzed using etches pit surface patterns with water.

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.

Quality crystals of 4-Methoxy Anilinium 5-Sulfo Salicylate (4MA5SS) were grown with the dimension of 9 mm × 6 mm × 3 mm from ethanol solution by slow evaporation solution growth technique. The cell parameters and crystal structure studied by single-crystal X-ray diffraction. FTIR spectroscopic studies were carried out to confirm the functional groups and vibrational modes present in the grown crystals. The linear optical properties of the grown crystal were studied from the UV–Vis spectrum. The surface laser damage threshold for the grown crystal was measured using Nd:YAG laser. Further, Vickers micro-hardness study was carried out to analyze the mechanical strength of the grown crystals for various loads. The dielectric measurements of this crystal in the frequency region from 50 Hz to 5 MHz showed that the material can be used for optical application.

Good quality single crystals of organic nonlinear optical material l-proline 2,4-dichlorobenzoic acid (LPDCBA) were synthesized and grown by slow evaporation technique. The lattice parameters and space group were determined using single crystal XRD analysis. The optical absorbance and the lower cut-off wavelength of the LPDCBA were identified by UV–VIS–NIR studies. The modes of vibrations of different molecular groups present in the sample were identified by the FTIR spectral analysis. Dielectric measurement of LPDCBA were carried out at different frequencies. Thermal stability of LPDCBA were determined by TGA/DTA measurements. Laser induced damage threshold study was carried out for the grown crystal using Nd:YAG laser. The second harmonic generation efficiency were found to be 1.66 times greater than that of KDP.

Good-quality new single crystals of 4-methylpyridinium 4-nitrobenzoate were grown by slow evaporation solution growth technique at room temperature using methanol as solvent. The structure of the c...

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.

This work aims at investigating the undoped Glycinium Oxalate (GO) and Manganese doped Glycinium Oxalate (Mn:GO) single crystals that were prepared via slow evaporation method. The single crystals grown were characterized for its structural, vibrational, optical, topographical, electrical and mechanical properties. Single and Powder X-ray diffraction suggests that the grown crystals are crystallized in the monoclinic structure. The functional groups and the effect of moisture on the undoped and doped GO crystals can be analyzed with the help of FTIR spectrum. The undoped and doped GO single crystal shows low absorption in the entire visible and IR region, which is suitable for optical device applications. The emission of green light with the use of Nd:YAG laser (λ = 1064 nm) confirmed the second harmonic generation properties of the grown crystals. Dielectric measurements were carried to the wide range of frequency (50 Hz–5 MHz) at different temperatures. The determined Vickers hardness number and work hardening coefficient of the grown crystals ascertains the soft nature of the crystal.

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.

The present work deals with flexural behavior of bottom ash geopolymer reinforced concrete beam. A total of twelve beams were cast, in which six beams were control reinforced concrete beams and six beams were bottom ash geopolymer reinforced concrete (BAGPRC) beam. BAGPRC beam was cured at ambient temperature. The load carrying capacity, load deflection behavior, initial stiffness, ductility factor and energy absorption capacity of beams were arrived and compared with control reinforced cement concrete (RCC) specimens. The test result reveals that BAGPRC exhibited excellent performance over control RCC beam. However, ductility index and stiffness behavior of BAGPRC beam were comparable with control RCC beam.