207 research outputs found
Risk Assessment Techniques for Civil Aviation Security
No full textFollowing the 9/11 terrorists attacks a strong economical effort was made to improve and adapt aviation security, both in infrastructures as in airplanes. National and international guidelines were promptly developed with the objective of creating a security management system able to supervise the identification of risks and the definition and optimisation of control measures.
Risk assessment techniques are thus crucial in the above process, since an incorrect risk identification and quantification can strongly affect both the security level as the investments needed to reach it.
The paper proposes a set of methodologies to qualitatively and quantitatively assess the risk in the security of civil aviation and the risk assessment process based on the threats, criticality and vulnerabilities concepts, highlighting their correlation in determining the level of risk.
RAMS techniques are applied to the airport security system in order to analyse the protection equipment for critical facilities located in air-side, allowing also the estimation of the importance of the security improving measures vs. their effectiveness
Unusual coordinating behavior by three non-steroidal anti-inflammatory drugs from the oxicam family towards copper(II). Synthesis, X-ray structure for copper(II)-isoxicam, -meloxicam and -cinnoxicam-derivative complexes, and cytotoxic activity for a copper(II)-piroxicam complex
No full textCytotoxic tests recently performed at National Cancer Institute, NCI (USA), on [Cu(HPIR)2(DMF)2], 1, (H2PIR = piroxicam, 4-hydroxy-2-methyl-N-pyridin-2-yl-2H-1,2-benzothiazine-3-carboxamide 1,1-dioxide) a widely used non-steroidal anti-inflammatory drug, NSAID [see R. Cini, G. Giorgi, A. Cinquantini, C. Rossi, M. Sabat, Inorg. Chem. 29 (1990) 5197–5200, for synthesis and structural characterization, DMF = dimethylformamide] (NSC #624662) by using a panel of ca. 50 human cancer cells, showed growth inhibition factor GI50 values as low as 20 ?M against several cancer lines, with an average value 54.4 ?M. The activity of 1 is larger against ovarian cancer cells, non-small lung cancer cells, melanoma cancer cells, and central nervous system cancer cells. The widely used anticancer drug carboplatin (cis-diammine(1,1-cyclobutanedicarboxylato)platinum(II)) (NSC #241240) has average GI50 value of 102 ?M. The reactions of copper(II)–acetate with other NSAIDs from the oxicam family were tested and crystalline complexes were obtained and characterized. Isoxicam (H2ISO = 4-hydroxy-2-methyl-N-(5-methylisoxazol-3-yl)-2H-1,2-benzothiazine-3-carboxamide 1,1-dioxide) produced [Cu(HISO)2] · 0.5DMF, 2 · 0.5DMF (DMF = dimethylfomamide). The coordination arrangement is square-planar and the HISO? anions behave as ambi-dentate chelators via O(amide),N(isoxazole) and O(enolate),O(amide) donors. Meloxicam (H2MEL = 4-hydroxy-2-methyl-N-(5-methyl-1,3-thiazol-2-yl)-2H-1,2-benzothiazine-3-carboxamide 1,1-dioxide) produced [Cu(HMEL)2(DMF)] · 0.25H2O, 3 · 0.25H2O. The coordination arrangement is square-pyramidal, the equatorial donors being O(amide),N(thiazole) from two HMEL? anions and the apical donor being O(DMF). Unexpectedly, cinnoxicam (HCIN = 2-methyl-1,1-dioxido-3-[(pyridin-2-ylamino)carbonyl]-2H-1,2-benzothiazin-4-yl-(3-phenylacrylate)) produced [Cu(MBT)2(PPA)2] (MBT = 3-(methoxycarbonyl)-2-methyl-2H-1,2-benzothiazin-4-olate 1,1-dioxide, PPA = 3-phenyl-N-pyridin-2-ylacrylamide)
X-ray structure and circular dichroism of pure rotamers of bis[guanosine-5-monophosphate(-1)](N,N,N',N' -tetramethylcyclohexyl-1,2-diamine)platinum(II) complexes that have R,R and S,S configurations at the asymmetric diamine
No full textThe use of a sterically hindered diamine ligand (Me4DACH) has allowed for the first time, the isolation and characterization, both in the solid state (X-ray crystallography) and in solution (circular dichroism), of pure Î HT rotamers of [Pt(Me4dach)(5â 2-GMP)2] (compounds 1 and 2 for R,R and S,S configurations of the Me4DACH ligand, respectively). Comparison of the CD spectra obtained for each rotamer, which differ only in the chirality of the Me4DACH ligand (R,R or S,S) or in the chirality of the HT conformation (Î or Î ), allowed us to conclude that, in the 200-350 nm range, the contributions to the overall CD spectrum that stem from diamine chirality and diamine-induced chirality of platinum dd transitions or from sugar chirality are negligible relative to the exciton chiral coupling that occurs for Ï -Ï * transitions of the cis guanines. Accurate molecular structures of 1·10D2O and 2·14D2O (conventional crystallographic agreement indexes R1 convergent to 2.07% and 2.18%, respectively) revealed that the crystallized rotamers have a Î HT conformation that is in agreement with all previously reported X-ray structures of [Pt(diamine)(nucleos(t)ide) 2] complexes. This conformation allows the 5â 2-phosphate to be located in proximity to the Me4DACH ligand so that (P)Oâ ̄HC(N) hydrogen-bond interactions exists in both complexes. For both structures, the canting of the guanine planes on the coordination plane is right-handed (R; canting angle (Ï ) of 80.9° and 73.2°, respectively); this indicates that the canting direction is driven by the HT conformation chirality (Î for both compounds) and not by the chirality of the carrier ligand (different for the two compounds). Density functional theory analysis of the conformational space as a function of Ï indicated a good agreement between the computed and experimental structures. The increase in energy for Ï values below 65° and 55° (for 1 and 2, respectively) is mainly due to the short intramolecular contacts between C(8)H and the cis N-Me groups on the same side of the platinum coordination plane
Recent Advances in Biomimetic Metal Phenolates
No full textThe review reports and critically comments on articles mostly published during the period 2012–2015, relevant to phenolate‐containing metal complexes, in the following fields: (i) antioxidants and O2 activation (Section III; copper complexes as models for amine oxidase and phenol‐like antioxidants from the OXICAM family of nonsteroidal anti‐inflammatory therapeutics), and (ii) efficient hydrolysis of phosphate diester bonds (Section IV). Remarkably, the review includes several other tasks grouped in Section V about phenolic chelators of iron, models for halophenol scavenger systems, phenols and their metal complexes designed for DNA cleavage, and synthesis of phenolate–metal complexes via radical reactions. The comments focus on the synthesis of complexes and their structural aspects, on spectroscopy, on reaction mechanisms, on computational analyses, and on biological implications of the compounds
Esperimento didattico sulla magnetostrizione
No full textTra gli esperimenti didattici offerti dal Laboratorio Didattico di Fisica Generale LAFIDIN presso la Facoltà di Ingegneria dell’Università Federico II ne contiamo ora uno sulla magnetostrizione in provini cilindrici ferromagnetici. L’apparato sperimentale consiste in due bobine di eccitazione magnetica alimentate a frequenza acustica che generano onde magnetoelastiche stazionarie nel provino e di un rivelatore di flusso magnetico (pick-up) che fornisce un segnale proporzionale all’ampiezza dell’onda magnetoelastica. Alimentando le bobine di eccitazione con segnali diversamente sfasati è possibile evidenziare al rivelatore l’effetto di interferenza delle onde magnetoelastiche da esse generate. Con questo dispositivo si possono sperimentare diversi effetti di fisica generale e misurare tra l’altro costanti elastiche e costanti di accoppiamento magnetoelastico
Analytical composition of flours through thermogravimetric and rheological combined methods
No full textThe suitability of thermogravimetric analysis (TGA) and rheology for predicting analytical composition of flour was verified. The percentage weight loss of flour samples in different temperature ranges and their analytical composition determined following the American Association of Cereal Chemists (AACC) approved methods were correlated. The moisture content determined by AACC method showed a strong correlation with the weight loss of dried samples in the temperature range 30 – 125°C. Similarly, the weight loss of fully swollen samples, determined by TGA in the temperature range of 30 – 125°C, perfectly correlated with the water-Solvent Retention Capacity (w-SRC) determined by standard method (AACC). The weight loss in the range 200 – 400°C revealed a good correlation with the starch content, while the weight loss in the range 400 – 600°C correlated with the gluten content. Finally, the so-called residue at 600°C (usually attributable to mineral content) correlated with the ash content (AACC standard method). The rheological parameters (G', G'' and tan δ) also showed a strong correlation with the analytical composition of analyzed flours. A perfect correlation was observed between the mineral content and the elastic modulus, as well as between both G' and G'' and the starch content. As the resilience of dough samples strongly depends on the relative amount of gliadins and glutenins, a strong correlation between the Gli/Glu ratio and tan δ was also found
Study of binary and ternary metal complexes containing the sulfato ligand: Molecular models for selected non-catalytic sites in sulfurylase
No full text[CdII(Î1⁄42-O2,Oâ 2, Oâ 3-SO4)(terpy)]2·2H2O, 1·2H2O (terpy, 2,2â 2:6â 2,2â 3-terpyridine) was obtained from the reaction of 3 CdSO4·8H2O with terpy and consists of centrosymmetric dimeric units in which the two Cd(terpy)2+ moieties are held together by two tridentate sulfato anions that act as chelators towards the two metal centres, one oxygen being tri-coordinate. This coordination mode for the sulfato ligand has never been reported before in the solid state. [ZnII(Î1⁄42-O,Oâ 2-SO4) (terpy)]2·2H2O, 2·2H2O, was obtained by using ZnSO4·7H2O through a procedure similar to that followed for 1·2H2O. Semi-empirical quantum mechanics and density functional structure optimisations were performed at the AM1 and Becke3LYP/(6-31 G**, S) levels. The computations reproduced well the main features of the Zn(Î1⁄42-O,Oâ 2-SO4)2Zn unit as found in 2. A [Zn(imidazole)2(O-OOCCH3)2 (O-SO4)]2- model was also optimised as a model for ATP-sulfurylase from Saccharomices cerevisae
Cisplatin analogs with sterically hindered 1,10-phenathrolines and aromatic bases or nucleobase derivatives.
No full textWater content quantification by FTIR in carboxymethyl cellulose food additive
No full textWater content quantification of raw polysaccharide materials for food processing is generally
performed by gravimetric analysis or titrimetric methods, which are time- and energy-consuming,
non-eco-friendly and sample destructive. The present study develops and validates a new
approach, based on the use of Fourier transform infrared (FTIR) spectroscopy, resulting in
a model of the water content of carboxymethyl cellulose (CMC) polysaccharides. Samples of CMC
were exposed to different relative humidity conditions. Water content was determined by standard
gravimetric methods (OIV-Oeno 404–2010) and compared with the area of FTIR absorption in the
range 3675–2980 cm−1, attributed to the stretching of OH groups. The strong correlation between
gravimetric results and FTIR area (R2 = 0.88) showed no signs of bias across the water content range.
A cross-validation technique to predict the water content by band area was assessed obtaining
a general equation: y = 2.12 x + 2.80 with a high repetitively and good prediction of the tested
models
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