Synthesis of SnO2 nanostructures by ultrasonic-assisted sol–gel method

Fluorine doped SnO₂ nanostructures were grown using ultrasonic assisted sol–gel method. The gel was obtained by dissolving stannous chloride in methanol with ammonium fluoride as dopant followed by irradiation with ultrasonic vibrations. Obtained samples were characterized by structural, morphological and optical studies. All the peaks in the X-ray diffractograms are identified and indexed as tetragonal cassiterite structure. Negative slope of Williamson–Hall plots indicates compressive strain. Particle size of SnO₂ nanostructures is decreases with increases in concentration of fluorine doping. Atomic force microscopy, scanning electron microscopy and transmission electron microscopy studies confirm the formation of ring like porous structures and then hollow tube like growth with increase in the fluorine concentration. Peaks in Raman spectra also indicate strong confinement in SnO₂ particles. Distinct peaks in the PL spectra make the structure suitable for photovoltaic applications.     

Chemical characterization of soda-lime glass samples by in situ current normalised PIGE and conventional INAA methods for forensic applications

Nuclear analytical methods namely in situ current normalised Particle Induced Gamma Ray Emission (PIGE) and conventional Instrumental Neutron Activation Analysis (INAA) were utilized for determining major, minor and trace concentrations of eighteen elements in five soda-lime (automobile) glass samples. Concentration of four major elements (Si, Na, Mg and Al) by PIGE and fourteen elements including ten trace elements by INAA were determined. For forensic application, major elements were used for confirming the class of glass samples, whereas concentration results of trace elements like transition and rare earth elements were utilized for finding similarity or differences among the glass samples.

     

Crystal and Molecular Structure of Tosyl Pyrrolidine-2-Methanol (C12H17SO3N)

C₁₂H₁₇SO₃N, M_r = 255.33, Orthorhombic, P2₁2₁2₁, a = 11.703(1) Å, b = 14.797(3) Å, c = 14.971(2) Å, V = 2592.52 ų, Z = 8, D_m = 1.309 Mgm⁻³, D_c = 1.308 Mgm⁻³, mμ = 21.57 cm⁻¹, F(000) = 1088, T = 290 K, final R = 0.080 for 2416 unique reflections. There are two crystallographically independent molecules in the unit cell of the title compound.     

Crystal structure of a daturalactone – A withanolide

The crystal structure of a daturalactone derivative has been determined by X-ray structural analysis. The compound crystallizes in orthorhomic space group P2₁2₁2₁ with cell parameters a - 15.141(1) Å, b - 18.425(1) Å, c - 19.251(2) Å. The structure was solved by direct methods and refined to R - 0.082. The asymmetric unit contains two non-equivalent molecules. Extensive hydrogen bonding is present. The conformations of the rings are A: a distorted half-chair, B: a perfect half-chair, C: a chair, D: an envelope-half chair and E: a twist boat. Ring junctions A/B, B/C, C/D are all trans fused. Methyl carbons C(18), C(19), C(27) and the lactone moiety is β-oriented whereas the methyl carbons C(21) and C(28) are α-oriented.     

Cobalt‐Embedded Nitrogen‐Rich Carbon Nanotubes Efficiently Catalyze Hydrogen Evolution Reaction at All pH Values

Despite being technically possible, splitting water to generate hydrogen is still practically unfeasible due mainly to the lack of sustainable and efficient catalysts for the half reactions involved. Herein we report the synthesis of cobalt‐embedded nitrogen‐rich carbon nanotubes (NRCNTs) that 1) can efficiently electrocatalyze the hydrogen evolution reaction (HER) with activities close to that of Pt and 2) function well under acidic, neutral or basic media alike, allowing them to be coupled with the best available oxygen‐evolving catalysts—which also play crucial roles in the overall water‐splitting reaction. The materials are synthesized by a simple, easily scalable synthetic route involving thermal treatment of Co²⁺‐embedded graphitic carbon nitride derived from inexpensive starting materials (dicyandiamide and CoCl₂). The materials’ efficient catalytic activity is mainly attributed to their nitrogen dopants and concomitant structural defects.     

Studies on testing and evaluation of platinum plated titanium electrode for production of uranous nitrate

Partitioning of plutonium from uranium is an important step in the reprocessing of spent fuel by PUREX process of solvent extraction using 30% TBP-dodecane. This is achieved by selectively reducing the Pu in solution to least extractable trivalent state by uranous nitrate as the reductant. The latter is conventionally produced by electrolytic reduction of uranyl ion in presence of hydrazine nitrate as uranous nitrate stabilizer using Pt-coated titanium as the anode. The anode plating wears out after period of operation thus affecting the process efficiency and hence the quality control testing of platinum plated electrode becomes important. This article describes the use of Beta backscattering method with strontium-90 radioisotope as non-destructive testing tool for measuring the coating thickness of the sample Ti electrode. The surface characteristics and coating morphology were also examined by scanning electron microscope and the micrographs are presented.     

Synthesis of cyclic α-hydrazino acids

Synthesis of five-, six-, seven-, eight-, and nine-membered cyclic α-hydrazino acids from a common starting material ‘diethylmalonate’ with 26, 16, 34, 13.5, and 13.33% overall yields is described. Sequential allylation or homoallylation and electrophilic amination followed by cyclization gave the desired rings. The methyl esters of eight- and nine-membered rings were synthesized by RCM and the corresponding free acids were generated after hydrolysis in the presence of 1 M BBr₃ solution in DCM.