Synthesis and Characterization of Single-Phase Cubic ZrO2 Spherical Nanocrystals by Decomposition Route

A simple thermal decomposition route has been developed to prepare single-phase cubic ZrO₂ nanospheres by [Zr(sal)₃(H₂O)₂](NO₃) as the new precursor. The ZrO₂ nanocrystals have been prepared by bis-aqua, tris-salicylaldehydato zirconium(IV) nitrate; [Zr(sal)₃(H₂O)₂](NO₃), as precursor in oleylamine (C₁₈H₃₇N) and triphenylphosphine (C₁₈H₁₅P). To control the particle size, combination of C₁₈H₃₇N and C₁₈H₁₅P were applied as surfactants. The C₁₈H₃₇N and C₁₈H₁₅P play an important role in preventing aggregation of ZrO₂ nanocrystals. The products were characterized by X-ray diffraction, transmission electron microscopy, photoluminescence spectroscopy, and Fourier transform infrared (FT-IR) spectroscopy to depict the phase and morphology. The FT-IR spectrum showed the purity of obtained ZrO₂ nanocrystals with cubic phase.     

Residual and Past Discrete Tsallis and Renyi Extropy with an Application to Softmax Function

In this paper, based on the discrete lifetime distribution, the residual and past of the Tsallis and Renyi extropy are introduced as new measures of information. Moreover, some of their properties and their relation to other measures are discussed. Furthermore, an example of a uniform distribution of the obtained models is given. Moreover, the softmax function can be used as a discrete probability distribution function with a unity sum. Thus, applying those measures to the softmax function for simulated and real data is demonstrated. Besides, for real data, the softmax data are fit to a convenient ARIMA model.     

Semiconductor Behavior and Room Temperature Ferromagnetism in e-Beam Evaporated Co/TiO2 Multilayer Thin Films

Physics of the Solid State - The Co/TiO2 multilayer thin films have been deposited by e-beam evaporation method on glass substrates in vacuum and annealed in air at 773 K for 1 h. The crystal...     

Lateritic minerals for decontamination of radionuclides

Naturally available lateritic minerals (LM) have been used on laboratory scale for the removal of Ce, Gd and Lu radionuclides from nuclear industry and reactor effluents. The adsorption behavior using radiotracers is reported, describing factors such as the nature and strength of acids, particle size, temperature and equilibration time which influence the adsorption mechanism. The interference of various anions and organic complexing agents on sorption of these radiotracers has also been considered. The optimized physico-chemical conditions and high loading capacities suggest an, effective use of LM for the isolation of the radionuclides from industrial and reactor effluents. Leaching studies made on pelletized LM loaded with the radionuclides indicate their potential for disposal in reduced solid form for a longer period.     

Human serum albumin interaction studies of a new copper(II) complex containing ceftobiprole drug using molecular modeling and multispectroscopic methods

A copper(II) complex containing the ceftobiprole drug and 1,10-phenanthroline (phen) has been synthesized and characterized by UV–vis, FT-IR and mass spectra, and elemental analysis. The binding interaction between [Cu(cef)(phen)Cl₂] complex and human serum albumin (HSA) was investigated using absorption, fluorescence emission and circular dichroism spectroscopies, and molecular docking. Thermodynamic parameters (ΔH < 0 and ΔS < 0) indicated that the hydrogen bond and van der Waals interactions played main roles in the binding of complex [Cu(cef)(phen)Cl₂] to HSA. The results of CD and UV–vis spectroscopy showed that the binding of [Cu(cef)(phen)Cl₂] to HSA induces some conformational changes in HSA. Displacement experiments predicted that the binding of [Cu(cef)(phen)Cl₂] complex to HSA is located within domain III, Sudlow’s site 2, and these observations were substantiated by molecular docking studies.     

<Superscript>68</Superscript>Ga-radiolabeled magnetic nanoparticles for PET–MRI imaging

In this study, magnetic multimodal nanoparticles with potential applications in magnetic- and nuclear-medicine imaging, magnetic resonance imaging, hyperthermia, and theranostic (therapeutic and diagnostic), applications were prepared by coating iron oxide nanoparticles with silica (core–shell), functionalizing with aminopropyltriethoxy silane and coupling with diethylenetriamine pentaacetic acid ligand (DTPA). Radiolabeling of core–shell–DTPA particles with ⁶⁸Ga radiometal was carried out through chelation of ⁶⁸Ga(III) ions by DTPA and was used for positron emission tomography. The biodistribution of the ⁶⁸Ga-radiolabeled magnetic nanoparticles compared to free ⁶⁸Ga(III) was checked in normal Balb/c mice up to 2 h.     

Synthesis,characterization and biological analysis of transition metal complexes with macro cyclic ligands derived from adipic acid,ethylenediamine with diethyloxalate and diethylmalonate

Macro-cyclic ligands from adipic acid, ethylenediamine with diethyloxalate and diethylmalonate and their respective metal complexes of Mn(II), Co(II), Ni(II), Cu(II), and Zn(II) with macro cyclic ligands (LO) and (LM) L [N,N′-bis(2-aminoethyl)hexanediamide] were synthesized successfully. These metal complexes were characterized by Fourier transform infrared, ultraviolet visible spectrometry, proton nuclear magnetic resonance spectroscopy, and mass Spectrometry, CHNS and thermogravimetric analysis. The elemental analysis confirms the structures for Mn(II), Co(II) and Ni(II) complexes similar to octahedral geometry, Cu(II) complexes as a square planar geometry and Zn(II) complexes in the tetrahedral geometry. The molar conductivities of all the metal complexes were taken in 10^?3 M DMSO, and values of all the metal complexes showed their electrolytic nature which indicates the presence of chloride ions. Thermal analysis supports as the metal complexes are thermally stable. The result of antimicrobial activity against various microorganisms confirms that the metal complexes are potent bactericides and fungicides than the ligand. Metal complexes of LO with Cu(II) and Zn(II) were found to be highly active against S. typhimurium than the complexes of LM.

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Cauliflower‐like NiCo2O4−Zn/Al Layered Double Hydroxide Nanocomposite as an Efficient Electrochemical Sensing Platform for Selective Pyridoxine Detection

In the present study, a cauliflower‐like NiCo₂O₄?Zn/Al layered double hydroxide (NiCo₂O₄?Zn/Al LDH) nanocomposite was used as a novel electrode material for the sensitive and selective determination of pyridoxine (vitamin B₆). The structure and morphology of the as‐prepared nanocomposite were characterized by X‐ray diffraction (XRD), FT‐IR, field emission scanning electron microscopy (FESEM) and energy dispersive X‐ray spectroscopy (EDX). The NiCo₂O₄?Zn/Al LDH nanocomposite exhibited excellent electrocatalytic ability in the oxidation of pyridoxine, which could result from the synergistic effect of the two components. The developed sensor also provided a selective determination of pyridoxine in the presence of other species such as vitamins (B₁, B₂, B₁₂ and ascorbic acid), inorganic ions and biomolecules. The fabricated sensor showed a good linear response for pyridoxine over the concentration ranges 2×10^?7–2.0×10^?4 mol L^?1 with a low detection limit of 8.6×10^?8 mol L^?1. Finally, the proposed method was successfully applied for the determination of pyridoxine in commercial tablets and plasma samples with satisfactory results. Furthermore, this novel sensor displayed superior benefits in terms of stability, sensitivity, repeatability and cost. The present work aims to expand NiCo₂O₄ based nanocomposites to sensor fields and promote the development of pyridoxine sensors.     

Complex formation of hydronium ion with several crown ethers in 1,2-dichloroethane,acetonitrile, and nitrobenzene solutions

A conductance study concerning the interaction between hydronium ion and several crown ethers in acetonitrile, nitrobenzene and 1,2-dichloroethane solutions has been carried out at 25°C. The stability constants of the resulting 1:1 complexes in acetonitrile and nitrobenzene solutions were determined from the molar conductance-mole ratio data and found to vary in the order 18C6>DB30C10>DC18C6>DB18C6>DB21C7>DB24C8>B15C5. In 1,2-dichloroethane solution, the complexation process results in the dissociation of ion pairs. There is an inverse relationship between the stabilities of the complexes and the Gutmann donicity of the solvents. In nitrobenzene solution, some evidence for the formation of a 2:1 sandwich adduct between the smaller crowns (i.e., B15C5 and 18-crowns) are observed from the molar conductance-mole ratio data which is supported by the¹H NMR data.