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Highlights • Sm3+ incorporation maintained single phase cubic structure of Ni-Co ferrite. • Lattice strain with Sm3+ was increased. • FESEM micrographs exhibited agglomeration of grains with size varying from 40–60 nm. • Saturation magnetization upto x = 0.1 was decreased while for x = 0.125 it increases. • Observed Canting effect reveal the non-collinear structure. Abstract Samarium doped nanoferrites Ni 0.5 Co 0.5 Sm x Fe 2−x O 4 with (x = 0.00, 0.025, 0.05, 0.075, 0.10, 0.125) samples were prepared by using auto-combustion route. XRD pattern analysis confirmed the single-phase cubic spinel structure with no evidence of secondary phase. It is observed that, the lattice constant decreased from 8.342 Å (x = 0) to 8.321 Å (0.100) and again increased to 8.370 for x = 0.125. The crystallite size and particle size indicate the nano sized nature of the prepared ferrites. Crystalite size varies nonlinearly between 33 nm and 25 nm with addition of Sm3+ content in Ni-Co nanoferrites. The agglomerated grain structure revealed the high surface interaction among magnetic nanoparticles. FTIR spectra revealed the characteristics features of ferrite skeleton formation. The saturation magnetization, coercivity and remanence magnetization are found to decreases with the substitution of Sm3+ ions. [ABSTRACT FROM AUTHOR]

Rare earth Neodymium (Nd 3+ ) doped nanocrystalline Ni-Co mixed spinel ferrites which are chemically represented as Ni 0.5 Co 0.5 Nd x Fe 2-x O 4 (x = 0.025 to 0.125, in the step of 0.025) were synthesized by sol-gel auto-combustion method. The structural, morphological, infrared and magnetic properties were studied in detail in the light of Nd 3+ doping using standard techniques. X-ray analysis reveals the formation of single phase cubic spinel structure for all the prepared samples without any impurity phase. The crystallite size calculated from Scherrer's formula was observed to be decreasing with increasing Nd 3+ content. The lattice parameter calculated using XRD data was found to be decreasing upto x = 0.100 and then increases for x = 0.125. X-ray density was observed to be increasing from 5.327 to 5.630 gm/cm 3 . Surface morphology was studied through scanning electron microscopy technique. Grain size calculated from SEM analysis was found to be in the range of 30–59 nm. From transmission electron microscopy study, the average particle size was observed to be in the range of 35–45 nm. FTIR results exhibit the characteristics cubic spinel ferrite nature of the samples with two prominent absorption bands near 400 cm −1 and 600 cm −1 . FTIR also confirms the incorporation of Nd 3+ in the crystal structure. The magnetic behavior shows strong influence of substitution of Nd 3+ ions. The saturation magnetization, coercivity and remenance magnetization all decrease with substitution of Nd 3+ ions up to x = 0.100. For further increase in Nd 3+ concentration (x = 0.125), the saturation magnetization found to be increased. [ABSTRACT FROM AUTHOR]

In current study, supercritical processed starch nanosponge (SSNS) used as a carrier for poorly water soluble drug (fenofibrate) to enhance its in-vitro and in-vivo performance. SSNS was prepared by using sol- gel method and effective supercritical drying technique. Fenofibrate was loaded into the SSNS by using solvent immersion method with selected and optimized organic solvent. BET surface area of SSNS was evaluated by nitrogen adsorption/desorption analysis. SSNS and drug loaded SSNS were characterized by DSC, XRPD, FTIR, SEM, Contact angle study and evaluated for in-vitro, in-vivo studies. The results revealed that the formed SSNS material has high surface area (180m2/gm) with pore size (40 nm to 200nm). The DSC and XRPD study revealed the amorphization of drug within a SSNS. SEM study showed the continuous porous structure with differ nanosized pores of SSNS. Contact angle study showed improvement in aqueous wetting property of drug within a SSNS. In-vitro drug release study showed remarkable dissolution enhancement of SSNS formulation as compared to plain drug. In vivo pharmacodynamic study (hyperlipidaemia model) showed SNSS based formulation significantly improved the bioavailability of drug. Thus SSNS carrier system has good potential to be explored as a delivery system for poorly water soluble drugs. [ABSTRACT FROM AUTHOR]

Abstract: Sn whiskers are thin filaments that grow spontaneously out of the surface of coatings on Cu and have become a critical reliability problem in Pb-free electronics. In this review, we focus on what creates the driving force for whiskers (or more rounded “hillocks”), and what determines where on the surface they will form. Experimental studies are reviewed that quantify the relationship between the Cu–Sn intermetallic (IMC) formation, stress in the layer and whisker/hillock density. Measurements of the mechanical properties show how stress relaxation in the Sn layer is intimately related to how much stress develops due to the IMC formation. Real-time scanning electron microscope (SEM)/focused ion beam (FIB) studies are described that illustrate the whisker/hillock growth process in detail. Whiskers are found to grow out of a single grain on the surface with little lateral growth while hillock growth is accompanied by extensive grain growth and crystallite rotation. Electron-backscattering detection (EBSD) shows the grain structure around where the whiskers/hillocks form, indicating that whiskers can grow out of pre-existing grains and do not require the nucleation of new grains. This has led to a picture in which stress builds up due to IMC growth and causes whiskers/hillocks to form at “weak grains”, i.e., grains that have a stress relaxation mechanism that becomes active at a lower stress than its neighbors. FEA (finite element analysis) calculations are used to simulate the evolving stress and whisker growth for several different mechanisms that may lead to “weak” grains. [Copyright &y& Elsevier]

Abstract: We report a new biopolymer electrolyte for dye sensitized solar cell application. To develop polymer electrolyte, potassium iodide have been added in agarose biopolymer matrix and characterized using various techniques like complex impedance spectroscopy, Infrared spectroscopy (IR), X-ray diffraction (XRD), scanning electron microscopy (SEM). Complex impedance spectroscopy shows many folds enhancement in ionic conductivity (σ) by salt doping and conductivity maxima was obtained near 60:40 composition. Infrared spectroscopy confirms the formation of composite nature. XRD revels the reduction of crystallinity by salt doping as well affirms the composite nature. Scanning electron microscopy (SEM) shows reduction in crystallinity of gel matrix by salt doping which is a known favorable condition for ionic conductivity enhancement. To further affirm the conductivity enhancement in the gel electrolyte system a theoretical hopping model is also described in details. A DSSC has been developed using maximum electrical conductivity film which shows 0.54% efficiency at 1 sun condition. [Copyright &y& Elsevier]

Abstract Gd3+-doped Ca 3 Al 2 O 6 (CA3) phosphor was synthesized using a combustion method. The crystal structure and the phase purity of the sample were characterized by X-ray powder diffraction (XRD). The surface morphology of the sample was studied using a scanning electronic microscope (SEM). The Gd3+-doped Ca 3 Al 2 O 6 phosphor showed an absorption band in the UV spectral region and a narrowband-UVB emission under the excitation of 273 nm. The narrowband-UVB emission at 314 nm corresponds to the 6P 7/2 → 8S 7/2 transition of the Gd3+. A dominant line in the region around g = 2.0 was observed in the electron spin resonance (ESR) spectrum of the prepared phosphor. [ABSTRACT FROM AUTHOR]

Abstract Undoped Y 2 O 3 and Gd3+-doped Y 2 O 3 samples were synthesized using a sol-gel method. The samples were characterized by X-ray powder diffraction (XRD), a scanning electron microscope (SEM), photoluminescence (PL), and electron paramagnetic resonance (EPR). The room-temperature PL spectrum was recorded to study the bands that are due to the Gd3+. The photoluminescence analyses of the sample confirm the presence of the Gd3+ ions in the Y 2 O 3 matrix. EPR spectra of the samples confirmed the presence of Gd3+ ions in Y3+ sites with cubic symmetry. [ABSTRACT FROM AUTHOR]

In this study, we have developed a gold nanoparticle based simple, rapid lateral flow assay (LFA) for detection of Indian Cobra venom (CV) and Russell’s viper venom (RV). Presently, there is no rapid, reliable, and field diagnostic test available in India, where snake bite cases are rampant. Therefore, this test has an immense potential from the public health point of view. The test is based on the principle of the paper immunochromatography assay for detection of two snake venom species using polyvalent antisnake venom antibodies (ASVA) raised in equines and species-specific antibodies (SSAbs) against venoms raised in rabbits for conjugation and impregnation respectively. The developed, snake envenomation detection immunoassay (SEDIA) was rapid, selective, and sensitive to detect venom concentrations up to 0.1 ng/ml. The functionality of SEDIA strips was confirmed by experimental envenomation in mice and the results obtained were specific for the corresponding venom. The SEDIA has a potential to be a field diagnostic test to detect snake envenomation and assist in saving lives of snakebite victims. [ABSTRACT FROM AUTHOR]