Biomedical subjects

F Cariati

Publications and source records attributed to F Cariati.

10 recordsLinked to original sources

PubMed2004

MSWI fly ash particle analysis by scanning electron microscopy-energy dispersive X-ray spectroscopy.

Municipal solid waste incinerator (MSWI) fly ash was investigated to study metal distribution on the particle surface. A detailed investigation into the distribution of chlorine, copper, iron, and zinc was carried out by electron microscopy coupled with X-ray fluorescence spectroscopy. Compositional and leaching test data were used to identify the correlation of significant variables and to formulate a hypothesis about metals speciation. The presence of copper chloride, iron, and zinc oxides was inferred. The iron and zinc accumulation in the submicron nuclei indicates that these metals came from the condensation of volatile species. As far as concerns copper, morphological data together with the element correlation study suggest that this element accumulates on particles involved in heterogeneous condensation processes. Furthermore, during such processes, particles of small size containing copper are formed.

Carbon↗

PubMed2002

Synthesis, structure, and second-order nonlinear optical properties of copper(II) and palladium(II) acentric complexes with N-salicylidene-N'-aroylhydrazine tridentate ligands.

Two new N-salicylidene-N'-aroylhydrazines ligands have been prepared: N-4-diethylaminosalicylidene-N'-4-nitrobenzoyl-hydrazine (L(1)) and N-4-diethylaminosalicylidene-N'-4-(4-nitrophenylethylidene)-benzoyl-hydrazine (L(2)). The ligands are properly functionalized with strong electron donor-acceptor groups and are of potential interest in second-order nonlinear optics (NLO). Dimeric copper(II) and palladium(II) complexes with L(1) and L(2) have been prepared, and, starting from these, mononuclear acentric adducts with pyridine as a further ligand have been prepared and characterized. The X-ray structures of three adducts are also reported. The NLO activity of the adducts has been determined by EFISH measurements giving mubeta values up to 1500 x 10(-48) esu for an incident wavelength of 1.907 microm.

Journal Article↗

PubMed2001

Extended polymorphism in copper(II) imidazolate polymers: a spectroscopic and XRPD structural study.

Copper(II) bisimidazolate affords five different polymorphs; of these, one was structurally characterized 40 years ago by standard single-crystal X-ray diffraction (Jarvis, J. A. J.; Wells, A. F. Acta Crystallogr. 1960, 13, 1027), while the remaining four, selectively prepared as pure polycrystalline phases, have been now studied by X-ray powder diffraction (XRPD) methods. Of the four new (blue, green, olive-green, and pink) phases, three were solved by the ab initio XRPD technique and refined by the Rietveld method, and the fourth phase (pink) could not be structurally characterized. Crystal data for [Cu(imidazolate)(2)](n): blue phase, a = 27.559(3) A, c = 5.3870(9) A, trigonal, R3 macro, Z = 54; green phase, a = 21.139(1) A, b = 19.080(1) A, c = 9.2842(8) A, orthorhombic, Ccca, Z = 20; olive-green phase, a = 11.7556(8) A, b = 23.422(2) A, c = 9.0727(9) A, beta = 104.993(5) degrees, monoclinic, C2/c, Z = 12. All polymorphs contain four-coordinate CuN(4) chromophores and (N,N')-exobidentate imidazolate ligands, but show different spectroscopic and structural properties, the latter ranging from 2D to different 3D networks of the PtS, sodalite, and moganite archetypes. The intermediacy of the [Cu(imidazole)(2)CO(3)]-H(2)O species in the synthesis of the blue polymorph has been confirmed by spectroscopic and thermal analyses. FTIR, Raman, and electronic spectra were correlated with the structural features revealed in the present work, and used to gain insight into the coordination geometry of copper(II) ions of the pink polymorph. In addition, the correct Raman spectrum for copper(II) bisimidazolate, common for all polymorphs, has been definitely determined.

Journal Article↗

PubMed2001

Thermal oxidation kinetics and mechanism of sludge from a wastewater treatment plant.

The organic fraction of a sludge from a wastewater biological treatment plant is characterized by the total organic carbon, TOC, content, cyclohexane and toluene extractions, and thermal desorptions in nitrogen and air flow at different temperatures. The inorganic fraction is characterized by water extraction, FT-IR spectroscopy, thermogravimetric analysis, and scanning electron microscopy/energy dispersion X-ray analysis. The thermal degradation rate of organic carbon is studied in batch experiments in air, in the 250-500 degrees C temperature range. The sample TOC is used to measure the decrease of reagent concentration with time. The TOC vs time data are well fitted by a generalized kinetic model, previously proposed for the MSWIs fly ash thermal degradation. The rate constants of the immediate carbon gasification, k2, and of the dissociative oxygen chemisorption, k1, followed by C(O) intermediate gasification, k3, together with activation and thermodynamic parameters are calculated. The rate determining step is the C(O) oxidation. The influence of desorbed or extracted organic compounds on kinetics and the role of the C(O) formation in explaining the reaction mechanism as well as the comparison with fly ash kinetics are discussed.

Gases↗

PubMed2001

Determination of the quadratic hyperpolarizability of trans-4-[4-(dimethylamino)styryl]pyridine and 5-dimethylamino-1,10-phenanthroline from solvatochromism of absorption and fluorescence spectra: a comparison with the electric-field-induced second-harmonic generation technique.

For fluorescent compounds, the combined use of absorption and emission solvatochromic data allows to estimate indirectly the cavity radius of the molecule in solution, a very critical parameter in the application of the solvatochromic method for the determination of the quadratic hyperpolarizability beta of dipolar molecules. For two test compounds, trans-4-[4-(dimethylamino)styryl]pyridine (DASP) and 5-dimethylamino-1,10-phenanthroline (DAPHEN), the beta values so obtained are compared with those obtained by the EFISH (Electric Field Induced Second-Harmonic generation) technique. For DAPHEN, the versatility of the method described in this work in the presence of more than one electronic transition contributing to the non-linear optical response is demonstrated.

Absorption↗

PubMed2000

Analytical characterization of municipal solid waste incinerator fly ash. Part II.

The synergy of the micro FT-IR (Fourier Transform-Infrared) and SEM-EDX (Scanning Electron Microscopy-Energy Dispersive X-ray) techniques has been shown to be particularly helpful and effective for the characterization of inorganic compounds in fly ashes. The experimental data obtained by these techniques have been interpreted in comparison with those of other techniques. The presence of calcium carbonate, some sulfates, ammonium nitrate, calcium hydrogen phosphate, some chlorides, some oxides and aluminium silicates have been verified.

Aluminum Silicates↗

PubMed2000

A spectroscopic and magnetic study of complexes of bis(2-benzothiazolyl)methanate and bis(2-benzoxazolyl)methanate with Co(II), Ni(II), Cu(II) and Zn(II).

The co-ordination geometry of the complexes M(bbtm)2 and M(bbom)2 (M: Co, Ni, Cu, Zn; bbtm, bis(2-benzothiazolyl)methanate; bbom, bis(2-benzoxazolyl)methanate) are discussed on the basis of their IR, Raman, resonance Raman, electronic and ESR spectra. Compounds of Ni, Co, Zn with both ligands and Cu(bbom)2 resulted to have a distorted tetrahedral geometry. The distortion towards a square planar geometry is more marked for the M(bbtm)2 series than for the M(bbom)2 one. It has been impossible to suggest a co-ordination geometry for Cu(bbtm)2, that probably has a polymeric structure.

Benzoxazoles↗

PubMed2000

Speciation and structure of copper(II) complexes with histidine-containing peptides in aqueous medium: a combined potentiometric and spectroscopic study.

The complex formation between copper(II) and some histidine-containing peptides has been investigated by means of potentiometric and spectroscopic measurements. Due to the interesting co-ordination mode towards copper(II), peptides with histidyl residue located in second position from the N-terminal amino group have been chosen. The stability constants evaluation has been performed by both pH-metric and ESR (room temperature) measurements; in this context a suitable computer program for the calculation of both stability constant values and the ESR spectrum for each complex has been written. Visible spectrophotometric and circular dichroism spectra, together with the isotropic ESR parameters, were used in order to propose a structure for each complex having a significant percentage of formation in solution.

Circular Dichroism↗

PubMed1994

Spectroscopic evaluation of interactions among trace elements and biogenic carbonates in the marine environment.

The interactions between trace elements and biogenic carbonates (marine mussel shells) in aqueous media were evaluated. The behaviour of Mn, Cu, Co, and Cd was investigated using spectrometric techniques (electrothermal atomic absorption, inductively coupled plasma atomic emission and electron paramagnetic resonance). The results obtained show that the metals considered do not form a distinct precipitated phase on the shell surfaces, but that they interact with the CaCO3. This study aimed to provide more information on the mechanisms involved in the storage of trace elements by the shells of marine bivalves. This would allow the use of mussel shells as an alternative to soft tissues for trace metal analyses in biological monitoring programmes.

Animals↗

PubMedDate not supplied

A key factor in modern protection of historic buildings: the assessment of penetration of water-repellent polymers into porous stone-materials.

From the 1960s on, the conservation of monuments and stone masonry has witnessed an increasing use of polymeric products during restoration interventions. Actual penetration depths reached by different polymers within the porous stone matrix are supposed to be key factors in determining the efficacy of the treatments themselves (besides, of course, the chemical-mineralogical nature of the stone and the chemical-physical characteristics of the various polymers). This work presents some preliminary results obtained on specimens of Noto calcarenite treated with various polymeric protective products. Samples were investigated with direct analytical methods (micro-ATR spectroscopy, SEM) in order to assess penetration depths reached by polymers inside the stone while reducing to a minimum the necessary manipulation of specimens. The obtained results highlighted the following trend in penetration depths for the various products tested: siloxane product > partially fluorinated acrylic resin > acrylic resin. Moreover, data obtained allowed to establish direct correlation between long term efficacy of products and relative penetration depths.

Acrylates↗