Search results for "Spectroscopy"
showing 10 items of 10293 documents
Pineapple peel biochar and lateritic soil as adsorbents for recovery of ammonium nitrogen from human urine.
2021
Abstract Human urine is a rich source of nitrogen which can be captured to supplement the existing sources of nitrogen fertilizers thus contributing to enhanced crop production. However, urine is the major contributor of macronutrients in municipal wastewater flows resulting into eutrophication of the receiving water bodies. Herein, pineapple peel biochar (PPB), and lateritic soil (LS) adsorbents were prepared for the safe removal of ammonium nitrogen (NH4+-N) from human urine solutions. Physicochemical properties of PPB, and LS were characterized by scanning electron microscopy-energy dispersive spectroscopy (SEM-EDS), X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy…
MCM-41 silica effect on gel polymer electrolytes based on thermoplastic polyurethane
2012
Abstract Polymer electrolytes were prepared from thermoplastic polyurethane with addition of mixture of N-ethyl(methylether)-N-methylpyrrolidinium trifluoromethanesulfonimide (PYRA12O1TFSI) ionic liquid, lithium bis(trifluoromethanesulfoneimide) salt and propylene carbonate. MCM-41 mesoporous silica was added in proportions ranging from 5 to 20 wt.% with respect to TPU. The electrolytes were characterized by thermogravimetric analysis, differential scanning calorimetry, linear voltammetry and impedance spectroscopy. The MCM-41 addition to the system was found to improve the electrochemical stability of the membranes and to reduce the gel electrolyte/metallic Li interfacial resistance. The f…
Microwave assisted synthesis and solid-state characterization of lithocholyl amides of isomeric aminopyridines
2011
Microwave (MW) assisted synthesis and solid state structural characterizations of novel lithocholyl amides of 2-, 3-, and 4-aminopyridine are reported. It is shown that the MW technique is a proper method in the preparation of N-lithocholyl amides of isomeric aminopyridines. It offers many advantages compared to conventional heating. The molecular and crystal structures as well as the polymorphic and hydrated forms of prepared conjugates with their thermodynamic stabilities have been characterized by means of high resolution liquid- and solid-state NMR spectroscopy, single crystal and powder X-ray diffraction, and thermogravimetric analysis. Owing to the many biological functions of bile ac…
Surface modification of luminescent lanthanide phosphate nanorods with cationic "Quat-primer" polymers.
2011
"Quat-primer" polymers bearing cationic groups were investigated as a surface modifier for Tb-doped cerium phosphate green-emitting fluorescent nanorods (NRs). The NRs were synthesized by a microwave process without using any complex agents or ligands and were characterized with different analytical tools such as X-ray diffraction, transmission electron microscopy, and fluorescence spectroscopy. Poly(ethyleneimine) partially quarternized with glycidyltrimethylammonium chloride was synthesized separately and characterized in detail. (1)H and (13)C NMR spectroscopic studies revealed that the quaternary ammonium group was covalently attached to the polymer. UV-vis spectroscopy was used to exam…
Efficient Conversion of Carbon Dioxide by Imidazolium-Based Cross-Linked Nanostructures Containing Polyhedral Oligomeric Silsesquioxane (POSS) Buildi…
2019
Polyhedral oligomeric silsesquioxanes (POSS) have been employed as molecular building blocks for the synthesis of imidazolium cross-linked networks, to be used as heterogeneous catalysts for the conversion of carbon dioxide into cyclic carbonates. Two hybrid materials with different nucleophilic species (bromide and iodide) have been prepared and characterized by means of elemental analysis, 13C and 29Si solid-state NMR spectroscopy, thermogravimetric analysis and IR spectroscopy. The solids were tested as the sole catalyst under metal- and solvent-free reaction conditions showing full selectivity toward the formation of cyclic carbonates. High turnover number (TON) and productivity values,…
A tris-oxovanadium pyrogallate complex: synthesis, structure, and magnetic and electronic properties
2021
International audience; With the aim of identifying new cation-phenolate complexes, we herein investigated the reactivity of pyrogallol (H(3)pgal) with vanadium salts. A trimetallic anionic complex was identified, and found to be formed under a broad set of reaction conditions. This complex, with the formula V3O3(pgal)(3)(3-), consists of three oxovanadium(iv) units connected together by three pyrogallate ligands to afford a bowl-shaped species presenting a pseudo 3-fold symmetry axis. Its crystal structure is reported, as well as its characterisation by a broad set of techniques, including powder X-ray diffraction, thermogravimetric analysis, infrared and Raman spectroscopy, and solid stat…
Ecocompatible Halloysite/Cucurbit[8]uril Hybrid as Efficient Nanosponge for Pollutants Removal
2016
Hybrid materials based on halloysite nanotubes (HNT) and cucurbit[8]uril (CB[8]) were prepared with the aim to obtain efficient nanosponges towards hydrocarbons both in liquid and vapor phases. The loading on both HNT surfaces and the hybrid morphology were evidenced by FTIR spectroscopy, thermogravimetric analysis and scanning electron microscopy. In order to highlight the interactions in the hybrid 13C {1H} CP-MAS NMR experiments were performed. The aqueous colloidal stability of HNT/CB[8] was highlighted through ζ potential and dynamic light scattering measurements. The HNT/CB[8] composite was employed as nanosponge to capture aromatic oils in aqueous phase as evidenced by fluorescence e…
Nafion® and polyaniline composite modification with Li and Mg ions
2019
Funding from European Union`s Horizon 2020 Research and Innovation Program project under grant agreement No 768789 is greatly acknowledged.
One step grafting of monomethoxy poly(ethylenglycol) during synthesis of maghemite nanoparticles in aqueous medium
2008
Abstract Grafting of silanated monomethoxy poly(ethylene glycol) (m-PEG) onto maghemite nanoparticles surface in aqueous medium through one step procedure was investigated. The major characteristic of this work is that the grafting of m-PEG was produced during the synthesis of maghemite nanoparticles. The maghemite nanoparticles were characterized by photon correlation spectroscopy (PCS), zeta potential measurement, X-ray diffraction (XRD), Raman spectroscopy, transmission electron microscopy (TEM), Fourier transform infrared spectrometer (FTIR), and X-ray photoelectron spectroscopy (XPS). The spinel structure of maghemite nanoparticles was verified and successful grafting of m-PEG was evid…
Effect of plasma treatment on the properties of Arundo Donax L. leaf fibres and its bio-based epoxy composites: A preliminary study
2016
Abstract A preliminary investigation about the effect of plasma treatment on the properties of natural fibres extracted from the leaf of the giant reed Arundo Donax L. and their compatibility with a bio-based epoxy resin is performed. To this aim, the influence of plasma treatment on the functional groups and on the thermal behaviour of fibre were investigated using Fourier transform infrared spectroscopy and thermogravimetric analysis. Moreover, the mechanical characterization of fibres was performed through fibre tensile tests. Short randomly oriented fibres/bio-based epoxy composites were manufactured by hand lay-up method followed by compression moulding, varying both fibres weight cont…