Observational and trial data suggest that poor maternal micronutrient status as a result of poor dietary quality before and during pregnancy impairs fetal growth and development. This chapter describes the development of palatable food supplements produced from locally available vegetarian foods that improve the quality of the diet of young Indian women living in Mumbai slums. A vehicle in the form of a cooked snack food that could be distributed daily was developed to provide the women with supplementary green leafy vegetables (GLVs), fruit and milk. The target nutrient content of the snack was defined based on intake data from the study population and the UK Estimated Average Requirement (EAR). The snack was analysed to measure these target nutrient levels and palatability was assessed. Several approaches were used to deliver the amount of GLVs, fruit and milk that were considered sufficient to have an impact on the women's nutritional status. A vehicle was developed that contained these micronutrient-rich foods and was palatable and acceptable to the women. Some of the target micronutrient levels were achieved using combinations of fresh GLVs, dried fruits and milk powder. Mean micronutrient levels of the final product (per serving) were: β-carotene 123 retinol equivalents; folate 68 µmg; riboflavin 0.14 mg; iron 4.9 mg; calcium 195 mg; vitamin B12 0.24 µmg. These values are between 12% and 43% of the UK EAR. To date, target vitamin C levels have not been achieved. It is possible to develop palatable, culturally acceptable and safe micronutrient-rich food supplements using a low-tech approach and locally available fresh and dehydrated ingredients.

One-step wet chemical method has been employed for the synthesis of silver (Ag) nanofluids followed by the preparation of polyvinyl pyrrolidone (PVP), polyvinyl alcohol (PVA) and PVP–PVA mixed-dispersant-stabilized nanofluids by varying the concentration ratio of dispersants for the viscosity and thermal conductivity analysis. The optical absorption studies indicate the presence of nanoparticles in the prepared fluids (or the formation of the silver nanoparticles). The shape and size of the nanoparticles are confirmed by the field emission scanning electron microscopy, and the particle size distribution and zeta potential analysis were carried out by using dynamic light scattering. It is observed that the thermal conductivity of Ag nanofluids increases with an increase in the dispersant concentration with respect to the temperature. The maximum thermal conductivity enhancement of Ag nanofluids was observed in the presence of an equimolar ratio of PVP–PVA (1:1:1) blends as stabilizers. Graphic abstract

In the present work, gold (Au), silver (Ag), and copper (Cu) based mono- and bimetallic NPs are prepared using a cost-effective facile wet chemical route. The pH for the synthesis is optimized in accordance with the optical spectra and supported by the finite difference time domain simulation studies. FESEM and TEM micrographs are used to analyze the morphology of the prepared nanoparticles. TEM images of bimetallic nanoparticles (BMPs) verified their bimetallic nature. XRD studies confirmed the formation of fcc-structured mono- and bimetallic NPs. Photoluminescence studies of the as-synthesized NPs are in good agreement with the previous publications. These synthesized NPs showed enhanced catalytic activity for the reduction/degradation of 4-nitrophenol, rhodamine B, and indigo carmine dyes in the presence of sodium borohydride (NaBH 4 ) compared to NaBH 4 alone. For the reduction of 4-nitrophenol, Au, Cu, and CuAg nanoparticles exhibited good catalytic efficiency compared to others, whereas for the degradation of rhodamine B and indigo carmine dyes the catalytic efficiency is comparatively high for CuAg BMPs. Furthermore, the antibacterial assay is carried out, and Ag NPs display effective antibacterial activity against Klebsiella pneumoniae , Salmonella ser. Typhimurium, Acinetobacter baumannii , Shigella flexneri , and Pseudomonas aeruginosa .

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Bimetallic nanoparticles (BNPs) have drawn significant attention due to their numerous applications. They demonstrate enhanced optical, electrical, thermal, and catalytic properties due to the synergistic effects of monometals present in them. In this work, CuAg and AuAg BNPs have been synthesized using a facile and economical chemical reduction method. Optical characterization was carried out using UV–visible spectroscopy, and effect of pH on optical absorbance was studied. For CuAg and AuAg BNPs, optimum pH was observed to be at 9.4 and 6.39, respectively. Morphological investigation confirms the average diameters of CuAg and AuAg BNPs were to be 65 nm and 30 nm, respectively. Photocatalytic property illustrates the reduction of 4-nitrophenol to 4-aminophenol with a 92% conversion percentage in the presence of CuAg BNPs in 4 min, and rate constant for the reaction was measured to be 8.98 × 10–3 s−1. But for the AuAg BNPs, the conversion percentage was 97% in 8 min and rate constant was found to be 7.95 × 10–3 s−1. Thermal conductivity and viscosity measurements of the nanofluids obtained with CuAg and AuAg BNPs have ascertained them to be efficient candidates for the heat transfer and catalytic applications. Graphic abstract

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Soldering is a physical process in which one metal melts and joins the other to form a strong bond, which further helps in electron conduction and increases the mechanical strength in any electronic circuits. The present work demonstrates the development of graphene-based flux comprising of 2 g of graphene and 2 ml of phosphoric acid for the residue-free, high stability, durable, and two-step soldering of copper wire on to the surface of the copper-based printed circuit board. The soldering flux can be applied to the copper, and wire can be soldered in ambient conditions using commercial soldering iron at a standard soldering temperature of 260℃. This flux helps the formation of strong and electrically conducting joints between the copper wire and copper-based printed circuit board. The joints are studied with scanning electron microscope images, and energy dispersive X-ray mapping successfully shows the formation of a joint between the copper wire and the copper and also shows the presence of graphene between the joint.

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