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The present article reports a simple and cost-effective process to prepare the crystalline MgAl2O4 spinel using non-stoichometric amount of magnesium nitrate, aluminium nitrate by solution combustion route. Thiourea was used as a fuel and reducing agent while soaking was carried at 1000ºC with different soaking periods. After slow drying of mixed solutions at 80ºC for 4-5 hours a gel was formed and got characterized by DTA/TGA (Differential Thermal Analysis and Thermal Gravimetric Analysis) to observe the effect of temperature variation and identify the range of temperature where crystalline nature of the powder was noted. Powder sample was prepared from the gel after annealing at 1000ºC followed by soaking for 4 hours, 5 hours, 6 hours to compare the variation of particle size with respect to time. The calcined powders were characterized by XRD (X-ray powder diffraction) to determine the phases and crystal planes present in the sample, FT-IR (Fourier-transform infrared spectroscopy) to study the types of metal oxide or metal-metal bond present in the sample along with M-O coordination studies, FESEM (Field emission scanning electron microscopy) to observe the morphological structure of the sample, EDAX (Energy Dispersive X-Ray Analysis) to observe the percentage of each element present in the sample. Bulk densities were estimated from 2.4156 g/cm3 to 2.8571 g/cm3 and the rapid increase in apparent porosity of samples 7.4289%, 10.3630% and 32.51% for 4 hours 5 hours and 6 hours respectively were also noted. It had been observed that the average crystal size of spinel particles was about 48 nm, 36 nm, and 47 nm respectively. Finally, hardness of spinel was evaluated by Vicker Hardness test and evaluated to be10.52GPa (1073 HV), 4.087GPa (416.7HV) and 5.079 GPa (517.9HV).

Barium bismuth titanate materials are noted for ferroelectric behavior, competitor to lead based relaxor dielectrics and even for coating having wear resistance, toughness for improving surface engineering applications. In the present context, a modified solid state process aided by agate-mortar activation for milling is carried in compare to mechanochemical milling, melt-quench method to generate the complex ceramic structure. Molar ratio of BaO:Bi2O3:TiO2 1:2:4 ratio have been taken with fixed soaking temperature to develop the material. Activation milling period is varied for 20 hours, 25 hours and 30 hours while soaking period descends in the order 10 hours, 8 hours and 6 hours keeping fixed temperature of about 700°C. XRD confirms the presence of peaks for all cases. Crystallite size is estimated by Scherrers formula with proper planes of index corresponding to JCPDS data. FTIR confirmed the phases developed by XRD while indicating the proper M-O bond formation from analysis in the required spectral range. EDX spectra analysis given the presence of required elements present in the sample.

Application of metal oxide nanoparticles for treatment of melanoma cells and microbes is being investigated. Zinc oxide nanoparticles (ZnO NPs) deserve special mention where particles cause destruction of melanoma cells with minimal damage to healthy cells. In the present study, pure phase ZnO NPs with particle size of 3.1 nm were synthesized by green route using algal extract. Skin melanoma (B16F10) cells were treated with synthesized ZnO NP and compared with commercial ZnO NPs and analysed for ED50 for cellular viability using 3% (w/v) of the doses. Sensitivity of B16F10 cells towards green synthesized ZnO NP was found to be more than commercial ZnO NPs. Results showed greater reduction in viability of cells exposed to green synthesized ZnO NPs and with increasing dose of the ZnO NPs, percentage viability of cells gradually reduced. 50% decrease in cellular viability (ED50) was obtained for green synthesized ZnO NP at 3% dose while commercial ZnO exhibited ED50 at 6% of doses. The ZnO NP also showed antimicrobial activity against Pseudomonas sp. and Staphylococcus sp. Zone of inhibition (ZOI) exhibited by Pseudomonas aeruginosa and Staphylococcus aureus for disc diffusion and well diffusion assay was around 10-22 mm and 9-12mm respectively.

Pharmaceutical and Personal Care Products (PPCPs) consists of diverse group of organic chemicals, which becomes a source of emerging concern, if their concentration in aqueous solution exceeds a certain limit. Ciprofloxacin, a frequently used antibiotic, gets excreted from body and its residues are found in water bodies. It is known to inhibit growth of microflora of ecosystem thereby posing great threat to environment. The present work focusses on novel approach of one step removal of ciprofloxacin from synthetic solution using nanocomposite ceramic ultrafiltration membrane based separation process. Copper oxide nanoparticles (CuO NP) synthesized by green route were used along with TiO2 nanoparticles (TiO2 NP) as composite to develop high flux ceramic ultrafiltration (UF) membrane over indigenously developed clay-alumina based macroporous support. The membrane was characterized in terms of X Ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR) to confirm about the membrane composition, field emission scanning electron microscopy (FESEM), Atomic Fluorescence Microscopy (AFM) was done to get an insight into the morphological properties, the permeation of the membrane was analyzed in terms of BET, clean water permeability, molecular weight cut-off (MWCO). FTIR analysis of membrane post filtration, suggested surface adsorption of ciprofloxacin on membrane and involvement of C O, COO , Ti O Ti and CuO groups in the process. Effect of various process parameters viz., transmembrane pressure (TMP), cross-flow velocity (CFV), operating time and feed concentration was observed on rejection efficiency of ciprofloxacin using the UF membrane. About 99.5% removal of ciprofloxacin was achieved within 60 min of operating time at 2.0 bar TMP and 2 Lmin-1 of CFV using a feed concentration of 500 μgL−1. Toxicity evaluation of membrane treated permeate was carried out in algae and impact on cellular components and stress enzymes were quantified, showing reduced effect on membrane treated permeate than untreated solution. The process thus targets in remediation of such emerging organic contaminants in a cost-effective, environmental-friendly way for production of clean permeate that can be safely disposed off in the environment.

Magnesium aluminate is synthesized utilizing precursors of Magnesium, aluminium nitrates in 1:2 molar ratios along with citric acid both as fuel and reducing agent. All precursors are mixed properly and undergo mild heat treatment in hot plate for partial combustion to obtain gel. Gel is made to dry and undergo annealing at 800°C for 5 hours to obtain the required phase. Thermal analysis is carried for the gel to determine spinelization temperature. Phase analysis by XRD is carried to determine the phase followed by bond information from FTIR analysis in terms of M-O co-ordinations. Morphology of the sample is analyzed by SEM to be uniform, spherical shape with little bit of agglomeration tendency.

Refractories as liners play an important role in the metallurgical, glassmaking, steel and ceramic industries. Spinel-based magnesium aluminate is an excellent refractory oxide for the production of high temperature materials focusing on emerging science and technology. It offers the attractive combination of physical and chemical properties like high mechanical strength at elevated temperature, a high melting point, high chemical inertness and thermal stability. Normally, this refractory material is prepared by energy-intensive high temperature solid state processing. Is there a way to synthesize Magnesium aluminate spinel over a solution combustion low temperature chemical route?

Emerging contaminants like phthalates and parabens in pharmaceuticals and personal care products pose threat to humans and environment because they are endocrine disruptors and are persistent in nature. Removal of these contaminants by conventional treatment methods has proven less effective in removing emerging contaminants. Ceramic ultrafiltration (UF) membrane developed indigenously from CuO/TiO2 nanoparticles effectively removed phthalates and parabens from synthetic systems (10–1000 ppb concentration) with removal efficiency of >99%. FTIR (Fourier Transform Infrared Spectroscopy) analysis suggested surface adsorption of phthalate and paraben on UF membrane. The effect of different parameters, viz. Transmembrane pressure (TMP), time, feed concentration on membrane filtration efficiency, was calculated by response surface methodology (RSM). Cytotoxic effects of untreated and membrane treated phthalate and paraben solutions were observed on ovarian teratocarcinoma (PA-1) cell lines. Cytotoxicity was evaluated by cell toxicity and reactive oxygen species (ROS) generation in culture PA-1 cells. Results showed that concentration IC50 (half maximal inhibitory concentration) values for phthalate untreated and treated samples were 54.9 μg/ml and 183.23 μg/ml respectively while for paraben untreated and treated samples were 16.8 μg/ml and 107.6 μg/ml respectively.

Discharges from pharmaceutical sectors into water bodies are major environmental issue as most of them are persistent in nature and causes endocrine disruption. Treatment processes presently undertaken are not effective in complete removal of these contaminants. Removal study of ibuprofen has been undertaken by adsorption and nanofiltration membrane whereas little knowledge of atenolol separation by membrane has been reported. Ceramic ultrafiltration membrane developed from green synthesized zinc oxide nanoparticles (ZnO NPs) was employed in this present study for removal of atenolol and ibuprofen drugs from synthetic solution. About 96 % and 99 % removal of atenolol and ibuprofen respectively was obtained by single step ultrafiltration process. UF membrane developed had surface area of 21.503 m2/g and pore diameter of 39.8 A. X-ray diffraction study of unsupported membrane showed pure phase crystalline zinc oxide particles. The effect of different parameters viz., TMP (Transmembrane pressure), time, feed concentration etc. on membrane filtration efficiency was analyzed by RSM (Response Surface Methodology). Germination studies on Vigna mungo was performed using untreated atenolol and ibuprofen solutions and membrane treated permeate to assess the membrane efficiency of producing clean water suitable for reuse. The study revealed higher germination rate in presence of ibuprofen solution but lower germination for atenolol solution. Protein content on the other hand were highly affected in both ibuprofen and atenolol solution. Seeds germinated in membrane permeate showed better germination rate and protein content and comparable to that of control.

Industrial and domestic discharges are contaminating surface water via bacterial infestations. Therefore, the present study focused on application of biogenically derived nanoparticles for elimination of such contaminants from water. Green synthesis of copper oxide nanoparticles (CuO NPs) by algal extract resulted in formation of nanoparticles with particle size of 3.6 nm. Effect of pH, concentration of algal extract, stirring speed and initial Cu2+ concentration, was studied and optimized. The synthesized particles showed antimicrobial activity against gram negative bacteria, Escherichia coli. Optimized dose of 50 μg/mL of NPs were found to be effective against Escherichia coli in surface water samples. Toxicity assay on fish model was conducted to analyze the probable toxic effect of CuO NPs on living system by observing formation of micronuclei in fish blood. No micronuclei were observed in fish blood after exposure to CuO NPs for 30 days. Cell death assay was conducted on mammalian cell lines, including human gastric epithelium (AGS) and Chinese hamster ovarian (CHO) by MTT (3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyl-tetrazolium bromide) assay which showed that cells had toxic effect of CuO NPs above 2.5% concentration indicating the potential use of the green synthesized CuO NPs in drinking water applications.