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21.
Ruggieri F Fanelli M Di Pasquale D Burri E Petitta M Mazzeo P 《Annali di chimica》2005,95(9-10):607-616
In the present work are reported the results of a monitoring on a vast scale, carried out through evaluation of opportune chemical parameters, of the pollution state of the agricultural-industrial settlement of the Fucino Plain. The parameters took into consideration have been the presence of wide consumption pesticides and of ionic species as Cl-, NO2-, NO3-, NH4+, the quantification of the dissolved oxygen, of the temperature, of the conductivity, of pH and eH. Collected data are used for chemometric elaboration. The water systems examined, by means of drawing campaigns carried out at regular intervals in winter, spring, summer, and autumnal seasons, are represented by superficial waters constituting a network of irrigation canals fed by stratum and meteoric waters. In this work are reported the results relative to the drawing campaigns. 相似文献
22.
We study the fully inhomogeneous Dirichlet problem for the Laplacian in bounded convex domains in Rn, when the size/smoothness of both the data and the solution are measured on scales of Besov and Triebel-Lizorkin spaces. As a preamble, we deal with the Dirichlet and Regularity problems for harmonic functions in convex domains, with optimal nontangential maximal function estimates. As a corollary, sharp estimates for the Green potential are obtained in a variety of contexts, including local Hardy spaces. A substantial part of this analysis applies to bounded semiconvex domains (i.e., Lipschitz domains satisfying a uniform exterior ball condition). 相似文献
23.
In this paper, we consider a new class CS*s,b of generalized close-to-starlike functions, which is defined by means of the Srivastava-Attiya operator Js,b involving the Hurwitz-Lerch Zeta function Φ(z, s, a). Basic results such as inclusion relations, coefficient inequalities and other interesting properties of this class are investigated. Relevant connections of some of the results presented here with those that were obtained in earlier investigations are pointed out briefly. 相似文献
24.
25.
Mihaela Dochia Dorina Chambre Simona Gavrilaş Cristian Moisă 《Journal of Thermal Analysis and Calorimetry》2018,132(3):1489-1498
The nature of the complexing agents used in the bioscouring process of cotton fabrics aiming to eliminate the non-cellulosic compounds (pectin, waxes, etc.) and to improve the hydrophilic and wetting properties influences the thermal behaviour and the FT-IR spectra of the textile materials. In this paper, we study the influence of the experimental conditions and complexing agent nature (sodium citrate or disodium EDTA salt) on the pectin elimination in bioscouring treatment of cotton fabric by FT-IR and TG/DTG/DTA analysis. The changes from FT-IR spectra of the specific bands (absorbance intensity at 2916, 2852, 1732 and 1640/1642 cm?1) were evaluated. The thermal behaviour of the investigated samples’ fabric by using TG/DTG/DTA analysis was studied at 30–600 °C temperature range, in air atmosphere. All samples showed three mass-loss steps due to the elimination of humidity, decomposition of the non-cellulosic and cellulosic components (main degradation stage of the samples) and thermo-oxidative decomposition of the formed degradation products. The Tonset values corresponding to the main decomposition step, the mass-loss values (%Δm) and the % residual mass (at 600 °C) were influenced by the complexing agent nature as well as the concentration and the action time of the commercial enzyme product. In addition, the calcium content of some samples treated with and without ultrasound was determined using atomic absorption spectroscopy method (AAS) in order to correlate the results with TG/DTG/DTA analysis. The obtained results have shown that the synergistic action of experimental conditions (enzyme concentration, pH, enzyme product action time, ultrasound) and the presence of sodium citrate as a biodegradable complexing agent led to the elimination of a higher amount of pectin from the cotton samples than that eliminated when using EDTA. 相似文献
26.
Dorina Mitrea 《Transactions of the American Mathematical Society》2008,360(7):3771-3793
Let be the solution operator for in , Tr on , where is a bounded domain in . B. E. J. Dahlberg proved that for a bounded Lipschitz domain maps boundedly into weak- and that there exists such that is bounded for . In this paper, we generalize this result by addressing two aspects. First we are also able to treat the solution operator corresponding to Neumann boundary conditions and, second, we prove mapping properties for these operators acting on Sobolev (rather than Lebesgue) spaces.
27.
Eva Zahorska Francesca Rosato Kai Stober Sakonwan Kuhaudomlarp Joscha Meiers Dirk Hauck Dorina Reith Emilie Gillon Katharina Rox Anne Imberty Winfried Römer Alexander Titz 《Angewandte Chemie (International ed. in English)》2023,62(7):e202215535
Bacterial adhesion, biofilm formation and host cell invasion of the ESKAPE pathogen Pseudomonas aeruginosa require the tetravalent lectins LecA and LecB, which are therefore drug targets to fight these infections. Recently, we have reported highly potent divalent galactosides as specific LecA inhibitors. However, they suffered from very low solubility and an intrinsic chemical instability due to two acylhydrazone motifs, which precluded further biological evaluation. Here, we isosterically substituted the acylhydrazones and systematically varied linker identity and length between the two galactosides necessary for LecA binding. The optimized divalent LecA ligands showed improved stability and were up to 1000-fold more soluble. Importantly, these properties now enabled their biological characterization. The lead compound L2 potently inhibited LecA binding to lung epithelial cells, restored wound closure in a scratch assay and reduced the invasiveness of P. aeruginosa into host cells. 相似文献
28.
Mazzeo P Di Pasquale D Ruggieri F Fanelli M D'Archivio AA Carlucci G 《Biomedical chromatography : BMC》2007,21(11):1166-1171
A high-performance liquid chromatographic method for the simultaneous determination of di(2-ethylhexyl)phthalate (DEHP) and its major metabolite mono(2-ethylhexyl)phthalate (MEHP) in seminal plasma was developed and validated. The method involves liquid-liquid extraction followed by isocratic reversed-phase chromatography with diode-array detection. The recovery, selectivity, linearity, precision and accuracy of the method were evaluated from the analysis of spiked seminal plasma samples. The effect of mobile-phase composition and pH on the retention of the target analytes was investigated. The limits of detection were 0.010 and 0.015 microg/mL, for DEHP and MEHP, respectively. This method was used to analyze real samples in support of clinical studies on these potential endocrine disruptors. 相似文献
29.
A new route for adding self‐healing properties to soluble polymers is presented briefly. Self‐healing block copolymers (polystyrene‐block‐polybutadiene block‐polystyrene from Sigma‐Aldrich) were obtained by dissolving the polymer in a solvent that neither dissolves the microbubbles nor deactivate the Grubbs catalyst. The self‐healing block copolymer has been obtained by mixing the polymer, the solvent, the microbubbles filled with monomer (dicyclopentadiene), and the Grubbs' catalyst followed by the evaporation of the solvent. The structure of self‐healed high elasticity block copolymer has been investigated by optical and Scanning Electron Microscopy. Raman spectroscopy and mechanical data suggested that the block copolymer exhibits self‐healing features. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
30.
Mihaela Dochia Monica Pustianu Cristian Moisă Dorina Chambre Simona Gavrilaş 《Chemical Papers》2018,72(8):1881-1888
A 50% of cotton–50% of flax fabric was subjected to an enzymatic treatment (bioscouring) in ultrasound for removing the compounds which could negatively affect the further specific technological processes as whitening and dyeing. During the scouring process, some parameters of the fabrics are improved. Even EDTA is usually used as a chelating agent in the pretreatments of the fabrics, recent studies aimed to identify new biodegradable complexing agents. In this study, we present the results obtained for bioscouring treatment of the cellulosic/lignocellulosic fabrics in the presence of sodium citrate as a complexing agent. The treatments were made in 0.1 M phosphate buffer of pH 8 and ultrasound media. The samples were immersed in an aliquot containing the commercial pectinolytic product BEISOL PRO, Denimcol Wash-RGN as a surfactant and sodium citrate or EDTA (ethylenediaminetetraacetic acid). The reactions were conducted by varying the enzyme concentration and action time using a central, rotatable second-order compound program. All the parameters determined after bioscouring [weight loss, hydrophilicity, whiteness index, yellowness index, tensile strength, elongation at break, the relative absorbance (A1731) from FT-IR spectra, color strength (K/S) and color difference (ΔE*ab)] of the investigated samples showed in the case of sodium citrate (an eco-friendly biodegradable compound) treatments better or comparable values to treatments conducted using EDTA (non-biodegradable compound). 相似文献