Search results for "spectroscopic analysi"
showing 6 items of 6 documents
Comprehensive Study on the Performance of Waste HDPE and LDPE Modified Asphalt Binders for Construction of Asphalt Pavements Application
2022
This research is aimed at investigating the mechanical behavior of the bitumen by the addition of high-density polyethylene (HDPE) and low-density polyethylene (LDPE) obtained from waste plastic bottles and bags. Polymers (HDPE and LDPE) with percentages of 0%, 2%, 4%, and 6% in shredded form by weight of bitumen were used to evaluate the spectroscopic, structural, morphological, and rheological properties of polymer-modified binders. The rheological properties for different factors; viscosity (ἠ) from Rotational Viscometer (RV), rutting factor G*/Sin (δ), fatigue characteristics G*. Sin (δ), for the modified binder from dynamic shear rheometer (DSR), Short and long-term a…
La pittura vascolare attica a fondo bianco: la prospettiva archeologica, l'apporto dell'indagine scientifica
2017
Il presente contributo intende offrire nuovi spunti di ricerca sui vasi attici a fondo bianco e sulla relativa tecnica pittorica. In particolare, è stato selezionato come caso di studio il cratere del Pittore della Phiale (450-440 a.C.) con il mito di Perseo e Andromeda, esposto nel Museo Archeologico di Agrigento. La prima parte del lavoro si concentra sugli aspetti archeologici e storico-artistici, cercando di ricostruire il ruolo di questa tecnica nella produzione figurativa dell’artigiano e il rapporto tra il cratere di Agrigento e gli altri prodotti del Pittore della Phiale. Inoltre, viene considerata la connessione tra tecnica e con- testo di utilizzo e acquirenti o “committenti”, la…
Lateral Fusion of Chemical Vapor Deposited N = 5 Armchair Graphene Nanoribbons
2017
Bottom-up synthesis of low-bandgap graphene nanoribbons with various widths is of great importance for their applications in electronic and optoelectronic devices. Here we demonstrate a synthesis of N = 5 armchair graphene nanoribbons (5-AGNRs) and their lateral fusion into wider AGNRs, by a chemical vapor deposition method. The efficient formation of 10- and 15- AGNRs is revealed by a combination of different spectroscopic methods, including Raman and UV−visnear-infrared spectroscopy as well as by scanning tunneling microscopy. The degree of fusion and thus the optical and electronic properties of the resulting GNRs can be controlled by the annealing temperature, providing GNR films with o…
Interaction of metal ions with N-glycosylamines: isolation and characterization of the products of 4,6-O-benzylidene-N-(o-carboxyphenyl)-β-D-glucopyr…
2001
Metal-ion complexes of Li+, Na+, K+, Mg2+, Ca2+, Ba2+, Pb2+, Cd2+, Hg2+ with 4,6–O–benzylidene–N–(o–carboxyphenyl)–β–D–glucopyranosylamine were synthesized and isolated as solid products and characterized by analytical means as well as by spectral techniques, such as, 1H and 13C NMR, FTIR, absorption, FAB mass spectrometry, optical rotation and CD. While the alkali metal ions formed ML type of complexes, the other metal ions formed ML2 type complexes. Molecular weights of the complexes of Li+, Na+ and K+ were established based on the molecular-ion peaks in the FAB mass spectra. The saccharide portion remians in the β-anomeric form even after the complexation. The spectral data, as well as t…
Synthesis, spectroscopic, and X-ray structural study of aqua-bis(thymine-N 1 ,N 4 )-ethylenediamine copper(II)dihydrate [Cu(Thy) 2 (en)(H 2 O)].2H 2 O
2016
International audience; A new compound of thyminato anions and ethylenediamine with five-coordinate Cu(II) is synthesized. Elemental analysis and spectroscopic techniques (IR, UV-visible) were used to characterize this compound and its crystal structure was determined by single-crystal X-ray diffraction. The crystal structure consists of the neutral mononuclear complex [Cu(Thy)(2)(en)(H2O)]center dot 2H(2)O. The environment around Cu(II) ion exhibits a square pyramidal geometry with two nitrogen atoms of ethylenediamine and two other nitrogen atoms of the monodentate monoanions of thymine building the equatorial plane. The oxygen atom from H2O molecule occupies the apical position. The comp…
Preparation of pH sensitive poly(vinilydenefluoride) porous membranes by grafting of acrylic acid assisted by supercritical carbon dioxide
2012
Free radical grafting of acrylic acid (AA) on poly(vinilydenefluoride) (PVDF) porous membranes was studied at 65°C using supercritical carbon dioxide (scCO 2) as a solvent and delivery agent. The process was initiated by the thermal decomposition of benzoylperoxide (BPO). Spectroscopic analyses confirmed the presence of poly(AA) chains linked to treated membranes. The mass fraction of grafted AA increased with grafting time and BPO concentration while it decreased when the density of the fluid phase was enhanced. A not-monotonic trend was obtained when the effect of the initial AA concentration was studied. The grafting process was accompanied by a reduction of the crystallinity of the PVDF…