Study of Size Distribution in Nanostructured Se<Subscript>58</Subscript>Ge<Subscript>39</Subscript>Pb<Subscript>3</Subscript> Glass Using Various Characterization Methods

The present paper aims at the study of size distribution of particles in nanostructured Se₅₈Ge₃₉Pb₃ glass using X-ray diffraction (XRD), Transmission electron microscopy (TEM) and UV–visible spectrophotometer. The thin film sample has been prepared using melt quenching technique and inert gas consolidation method. The particle size distribution obtained from XRD and UV–Vis spectrophotometer shows more uncertainty than the results obtained from TEM measurements. The absorption spectra recorded on UV–Vis spectrophotometer is employed to get band gap values corresponding to different size distribution in sample. Further, it is concluded that TEM is the best measurement technique for size distribution as it has less uncertainty in the obtained results.     

A Comparative Study of Superconductivity and Thermally Activated Flux Flow of YBa2Cu3O7-δ and YBa2Cu3O7-δ/La1-x-yPrxCayMnO3 Bilayers

Journal of Superconductivity and Novel Magnetism - YBa2Cu3O7-δ/La1-x-yPrxCayMnO3 (YBCO/LPCMO) (x?~?0.31, y?~?0.35) bilayers with fixed ferromagnetic layer thickness...     

ResearchGate and Google Scholar: how much do they differ in publications,citations and different metrics and why?

ResearchGate has emerged as a popular professional network for scientists and researchers in a very short span. Similar to Google Scholar, the ResearchGate indexing uses an automatic crawling algorithm that extracts bibliographic data, citations, and other information about scholarly articles from various sources. However, it has been observed that the two platforms often show different publication and citation data for the same institutions, journals, and authors. While several previous studies analysed different aspects of ResearchGate and Google Scholar, the quantum of differences in publications, citations, and metrics between the two and the probable reasons for the same are not explored much. This article, therefore, attempts to bridge this research gap by analysing and measuring the differences in publications, citations, and different metrics of the two platforms for a large data set of highly cited authors. The results indicate that there are significantly high differences in publications and citations for the same authors captured by the two platforms, with Google Scholar having higher counts for a vast majority of the cases. The different metrics computed by the two platforms also differ in their values, showing different degrees of correlation. The coverage policy, indexing errors, author attribution mechanism, and strategy to deal with predatory publishing are found to be the main probable reasons for the differences in the two platforms.

     

Measurement of focal length with phase-shifting Talbot interferometry

Phase-shifting interferometry with a Fourier fringe analysis technique is implemented to analyze Talbot interferometric fringes and to evaluate the focal length of a lens. A four-step algorithm is used to obtain the phase map of the lens. The slope of the phase map is related to the focal length, and it is from this relationship that we evaluate the focal length. Experimental results are presented. Our experimental study suggests that phase-shifting Talbot interferometry combined with a Fourier fringe analysis technique can be advantageously used to improve the accuracy of measurement.     

The effect of citrate, oxalate, acetate, silicate and phosphate on stability of synthetic arsenic-loaded ferrihydrite and Al-ferrihydrite

The effect of the organic species oxalate, citrate and acetate and the inorganic species silicate and phosphate on release of As(V) from synthetic arsenic-loaded ferrihydrite and Al-ferrihydrite in the pH range 4-8 was investigated. For ferrihydrite, the organic species increased %As(V) extraction in the order: acetatePO4(3-). Competitive adsorption of the investigated organic and inorganic species on ferrihydrite and Al-ferrihydrite could explain the enhanced release of As(V) into solution. However, disproportionate adsorption of other species relative to amount of As(V) release occurs, suggesting that mechanisms other than competitive adsorption are also operative. The results could best be explained in terms of combination of competitive adsorption and processes involving pH-dependent dissolution of ferrihydrite/Al-ferrihydrite, formation of various complex ionic species involving Al(III), Fe(III), As(V), SiO3(2-), PO4(3-), OH-, H+ and organic species: acetate, oxalate and citrate.     

Impact of various solid carriers and spray drying on pre/post compression properties of solid SNEDDS loaded with glimepiride: in vitro-ex vivo evaluation and cytotoxicity assessment

Development of self-nanoemulsifying drug delivery systems (SNEDDS) of glimepiride is reported with the aim to achieve its oral delivery. Lauroglycol FCC, Tween-80, and ethanol were used as oil, surfactant, and co-surfactant, respectively as independent variables. The optimized composition of SNEDDS formulation (F1) was 10% v/v Lauroglycol FCC, 45% v/v Tween 80, 45% v/v ethanol, and 0.005% w/v glimepiride. Further, the optimized liquid SNEDDS were solidified through spray drying using various hydrophilic and hydrophobic carriers. Among the various carriers, Aerosil 200 was found to provide desirable flow, compression, dissolution, and diffusion. Both, liquid and solid-SNEDDS have shown release of more than 90% within 10?min. Results of permeation studies performed on Caco-2 cell showed that optimized SNEDDS exhibited 1.54 times higher drug permeation amount and 0.57 times lower drug excretion amount than that of market tablets at 4?hours (p?p?>?.05, i.e. 0.74). The formulation was found stable with temperature variation and freeze thaw cycles in terms of droplet size, zeta potential, drug precipitation and phase separation. Crystalline glimepiride was observed in amorphous state in solid SNEDDS when characterized through DSC, PXRD, and FT-IR studies. The study revealed successful formulation of SNEDDS for glimepiride.     

Preparation,characterization, and in vivo evaluation of nano formulations of ferulic acid in diabetic wound healing

Diabetes mellitus is most common disorder characterize by hyperglycemia. Chronic hyperglycemia may lead to over production of free radicals thereby results in oxidative stress which impaired healing of wounds. Ferulic acid (FA) has been shown to have antidiabetic and antioxidant properties. The aim of the present study was to develop Ferulic acid nanoparticles and to study its hypoglycemic and wound healing activities. Ferulic acid-poly(lactic-co-glycolic acid) (FA-PLGA) nanoparticles were prepared by nano precipitation method. The prepared FA-PLGA nanoparticles had an average size of 240?nm. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) analysis showed the prepared FA-PLGA nanoparticles were spherical in shape. Drug encapsulation assay showed that 88.49% FA was encapsulated in PLGA. Carbopol 980 was used to formulate FA-PLGA nanoparticles loaded hydrogel. FA-loaded polymeric nanoparticles dispersion (oral administration) and FA-loaded polymeric nanoparticles based hydrogel (topical administration) treated wounds were found to epithelize faster as compared with diabetic wound control group. The hydroxyproline content increased significantly when compared with diabetic wound control. Therefore, the results indicate that FA significantly promotes wound healing in diabetic rats.     

Fabrication and analysis of spatially uniform field electrokinetic flow devices: theory and experiment

A uniform-field design approach can improve the performance of microanalytical, chip-based devices for a number of applications, including separations and sample preparation. The faceted prism paradigm allows the design of microfluidic devices possessing spatially uniform fields in electrokinetically driven flows. We present the first quantitative study of the velocity fields obtained using faceted interfaces between deep and shallow channel sections. Electrokinetic flows were generated in a series of wet-etch fabricated microfluidic channels. The resulting velocity fields were analyzed by particle image velocimetry and compared with simulations of the two-dimensional Laplace equation using both the designed channel geometry and the as-fabricated channel geometry. This analysis found localized differences between the designed and observed flow fields that were directly attributable to the limitations of isotropic substrate etching. Simulations using the as-fabricated channel geometry reproduced the experimental electrokinetic velocity field, quantitatively accounting for speed field variations due to the limits of the fabrication method. The electrokinetic speed fields were also compared to corresponding pressure-driven speed fields.     

Realizing high thermoelectric performance in p-type RbZn4P3 Zintl compound: a first-principles investigation

Journal of Materials Science - This work presents structural, elastic, electronic, and thermoelectric properties of a tetragonal Zintl compound RbZn4P3, using the Density Functional Theory and...     

Effect of interface coupling between polarization and magnetization in La0.7Pb0.3MnO3 (LPMO)/P(VDF-TrFE) flexible nanocomposite films

Journal of Materials Science - La0.7Pb0.3MnO3(LPMO) nanoparticles (NPs) were prepared by sol–gel auto-combustion method. These were embedded in P(VDF-TrFE) to form (0–3) nanocomposite...