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1.
Monia Renzi Antonietta Specchiulli Davide Baroni Tommaso Scirocco Lucrezia Cilenti Silvia Focardi 《International journal of environmental analytical chemistry》2013,93(6):676-697
Samples of surface sediments and tissues (liver and muscle) of commercially available European silver eels (Anguilla anguilla L.) collected from Varano lagoon (Italy) were analysed to determine trace element contents. Univariate and multivariate analyses were performed to highlight both the differences between sampling sites and the influence of channel discharges. Atomic ratios indices for sediment data and biological enrichment factors (BEF) for eel tissues were calculated in order to evaluate the enrichment factor due to human activities. The highest levels of As (11.9?µg?g?1) and Zn (14.1?µg?g?1) were observed in the south-eastern zone of the lagoon, which is influenced by urban and agricultural discharges. The low levels of Hg observed in this study (0.04?µg?g?1) led us to exclude both natural and human local sources of this element. Trace element concentrations of all elements were lower in muscle than in liver tissue. Significant enrichment of Cu and Zn was found in livers. 相似文献
2.
Francesco A Bottino Anna Rosa Cinquegrani Giovanna Di Pasquale Leonardi Lucrezia Antonino Pollicino 《European Polymer Journal》2003,39(11):2203-2208
A series of new poly(arylene ether sulfone)s has been obtained by solution condensation polymerisation starting from 1,5- and 2,6-bis-(4-fluorosulfonyl)naphthalene with various aromatic dihydroxy compounds. The polymers, obtained in quantitative yields, possessed inherent viscosities in the range 0.28-0.68 dl g−1, had good thermal stability (10% weight loss temperatures were above 405 and 420 °C respectively in nitrogen and air) and high glass transition temperatures (in the range 217-258 °C). They have been characterised by elemental and infrared analyses, GPC and wide-angle X-ray diffraction. The properties of these poly(arylene ether sulfone)s have been compared with those of the corresponding poly(arylene ether ketone)s. 相似文献
3.
Anna Verdino Gaetano DUrso Carmen Tammone Bernardina Scafuri Lucrezia Catapano Anna Marabotti 《Molecules (Basel, Switzerland)》2021,26(19)
Classic galactosemia is an inborn error of metabolism associated with mutations that impair the activity and the stability of galactose-1-phosphate uridylyltransferase (GALT), catalyzing the third step in galactose metabolism. To date, no treatments (including dietary galactose deprivation) are able to prevent or alleviate the long-term complications affecting galactosemic patients. Evidence that arginine is able to improve the activity of the human enzyme expressed in a prokaryotic model of classic galactosemia has induced researchers to suppose that this amino acid could act as a pharmacochaperone, but no effects were detected in four galactosemic patients treated with this amino acid. Given that no molecular characterizations of the possible effects of arginine on GALT have been performed, and given that the samples of patients treated with arginine are extremely limited for drawing definitive conclusions at the clinical level, we performed computational simulations in order to predict the interactions (if any) between this amino acid and the enzyme. Our results do not support the possibility that arginine could function as a pharmacochaperone for GALT, but information obtained by this study could be useful for identifying, in the future, possible pharmacochaperones for this enzyme. 相似文献
4.
García Ruano JL Torrente E Alonso I Rodriguez M Martín-Castro AM Degl'Innocenti A Frateschi L Capperucci A 《The Journal of organic chemistry》2012,77(4):1974-1982
Phenylselenyl benzylcarbanion stabilized by an (S)-2-p-tolylsulfinyl group evolves in a highly stereoselective way in the reactions with (S)-N-(p-tolylsulfinyl)imines at -98 °C affording diastereomerically pure 1,2-selenoamino derivatives in good yields. The syn or anti relationship of the obtained compounds depends on the alkyl or aryl character of the imine. They are easily transformed into enantiomerically pure (1R,2S)-1-aryl[or (1S,2S)-1-alkyl]-2-(phenylseleno)-2-phenylethylamines by reaction with t-BuLi and subsequent methanolysis of the generated sulfinamide derivatives with TFA. 相似文献
5.
In this paper the solid phase synthesis of various substituted purines is described starting from 4,6-dichloro-5-nitropyrimidine. The 4,6-dichloro-5-nitropyrimidine was coupled to Rink amide resin followed by displacement of the second chloride by an amino compound. Reduction of the nitro compound proved to be problematic but was achieved using lithium aluminum hydride/aluminum trichloride. The diamines (13) were then elaborated to purines by three different routes. 相似文献
6.
Lucrezia Palummo Andrea Bearzotti 《Applied Physics A: Materials Science & Processing》2009,97(4):835-839
Linseed oil is a material widely used in various applications as a protecting layer for surfaces in industry, in scientific
research, for medical use, and finally for artistic purpose. This natural origins substance has a particular application as
a protective and smoothing layer on phenolic-melaminic laminate electrodes on Resistive Plate Chamber (RPC) detectors used
in various particle physic experiments. In such electronic applications where linseed oil could be exposed to water vapours,
an electrical characterization should result useful for having an overall control of the process involving the oil. In this
paper, we studied the electrical behaviour towards relative humidity variations of linseed oil films deposited on interdigitated
metal electrodes. Moreover, I/V characterisation both in air and vacuum, current vs. temperature and relative humidity was
performed. 相似文献
7.
Simona Manuguerra Letteria Caccamo Monique Mancuso Rosaria Arena Alessandro C. Rappazzo Lucrezia Genovese 《Natural product research》2020,34(11):1567-1570
AbstractArmoracia rusticana (AR) was tested for antimicrobial and antioxidants power. The compound demonstrated to inhibit fish pathogens such as Vibrio anguillarum, V. harvey, V. alginolyticus, Aeromonas hydrophila, A. salmonicida, Photobacterium damselae subspecie piscicida, Tenacibaculum marinum and Pseudomonas anguilliseptica,. The total phenolic content and the reducing power resulted higher in the water extract of AR, respect to the hydroalcoolic. In vitro test demonstrated that AR significantly protect cells against death, induced by oxidative stress. 相似文献
8.
Detto F Armani N Lazzarini L Toccoli T Verucchi R Aversa L Nardi MV Rossi B Salviati G Iannotta S 《Physical chemistry chemical physics : PCCP》2012,14(16):5705-5710
Unprecedented room temperature excitonic emissions are achieved from TiO(2) nanocrystals synthesized at 300 K by supersonic cluster beams. Transmission electron microscopy studies show the crystalline nature of the nanoparticles (NPs) with a diameter ranging from 5 to 30 nm. All the samples show mixed rutile and anatase phases as confirmed by Raman spectroscopy. XPS core level analyses evidence an O/Ti ratio of the as-grown nanoparticles of 2.30 ± 0.04. Two room temperature cathodoluminescence excitonic peaks observed at 3.16 and 3.25 eV are ascribed to the coexistence of rutile and anatase crystallographic phases respectively. Subsequent thermal treatments at 450 °C cause the complete quenching of the UV excitonic emissions and result in a more conventional broad visible band centered at 2.5 eV. HRTEM and XPS studies reveal that, after annealing, the NPs remain single crystals in nature with an O/Ti ratio of 2.20 ± 0.04. These results suggest a correlation between the emission properties and the oxygen concentration of our NPs. The achieved ability to tune the optical properties of TiO(2) nanoparticles is very promising for sensing and energy applications. 相似文献
9.
Sebastian Govaerts Lucrezia Angelini Charlotte Hampton Laia Malet‐Sanz Alessandro Ruffoni Daniele Leonori 《Angewandte Chemie (International ed. in English)》2020,59(35):15021-15028
Vicinal diamines are ubiquitous materials in organic and medicinal chemistry. The direct coupling of olefins and amines would be an ideal approach to construct these motifs. However, alkene diamination remains a long‐standing challenge in organic synthesis, especially when using two different amine components. We report a general strategy for the direct and selective assembly of vicinal 1,2‐diamines using readily available olefin and amine building blocks. This mild and straightforward approach involves in situ formation and photoinduced activation of N‐chloroamines to give aminium radicals that enable efficient alkene aminochlorination. Owing to the ambiphilic nature of the β‐chloroamines produced, conversion into tetra‐alkyl aziridinium ions was possible, thus enabling diamination by regioselective ring‐opening with primary or secondary amines. This strategy streamlines the preparation of vicinal diamines from multistep sequences to a single chemical transformation. 相似文献
10.
Francesco Portioli Claudia Casapulla Lucrezia Cascini Mario D’Aniello Raffaele Landolfo 《Archive of Applied Mechanics (Ingenieur Archiv)》2013,83(10):1415-1438
In this paper, a formulation for limit analysis of three-dimensional masonry structures discretized as rigid block assemblages interacting through no-tension and frictional contact interfaces is developed. Linear and piecewise linearized yield functions are used for rocking, sliding and torsion failure. A simple yield condition has been defined to take into account interaction effects of shear force with torsion and bending moment. Associative flow rules are considered for strain rates. On the basis of the developed governing equations, the limit analysis problem has been formulated as a nonlinear mathematical program. An iterative solution procedure based on linear programming is used to solve the limit analysis problem and to take into account nonlinearities due to the influence of bending moments and shear stresses on torsion strength. The results of experimental investigations on out-of-plane masonry walls constrained at one edge and different examples from literature were considered for validation. Comparison with existing formulations is carried out. 相似文献