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91.
Producing solvent-resistant microfluidic devices is a challenge for analytical chemistry and biochemistry. We demonstrate a simple and low-cost fabrication approach for the realization of solvent-resistant microchannels based on perfluoropolyether elastomers, exhibiting very low aspect ratios (0.01). The strength of the microchannels sealing is evaluated through the maximum internal pressure (1.52 MPa) prior to device failure, due to delamination at the bonded interface. This approach allows the elastic properties of silicone elastomers, suitable for high quality external connections, to be combined with the non-swelling character of perfluoropolyethers. 相似文献
92.
Iacopo Ciabatti Cristina Femoni Mohammad Hayatifar Maria Carmela Iapalucci Irene Maggiore Stefano Stagni Stefano Zacchini 《Journal of Cluster Science》2016,27(2):431-456
The reaction of [Fe4C(CO)12{Cu(MeCN)}2] (1) with 3 equivalents of L–L (phen or Me2phen) affords [Cu(L–L)2][Fe4C(CO)12{Cu(L–L)}] (L–L = phen, 2; Me2phen, 3) in good yields. These are protonated by strong acids resulting in [HFe4C(CO)12{Cu(L–L)}] (L–L = phen, 4; Me2phen, 5). The reaction may be reversed with bases, resulting in the quaternary ammonium salts [NR4][Fe4C(CO)12{Cu(phen)}] (6). 4 and 5 react with a slight excess of L–L resulting in the elimination of copper in the form of [Cu(L–L)2]+ and formation of the previously reported [HFe4C(CO)12]? homometallic cluster. Conversely, the reaction of 1 with a monodentate N-ligand such as quinoline, even if used in large excess, results in the substitution product [Fe4C(CO)12{Cu(quinoline)}2] (8), which is then transformed into [Cu(Me2phen)2] [Fe4C(CO)12{Cu(quinoline)}] (9) after reaction with Me2phen. By using the anionic cluster [Fe5C(CO)14{Cu(MeCN)}]? instead of the neutral 1, only substitution has been observed by using both phen and quinoline, resulting in [Fe5C(CO)14{Cu(phen)}]? (10) and [Fe5C(CO)14{Cu(quinoline)}]? (11), respectively. Finally, the reaction of 1 with [Ru(tpy)(bpy)(N4C-C6H4-CN)]Cl affords crystals of [Fe4C(CO)12Cu2Cl{Ru(tpy)(bpy)(N4C-C6H4-CN)}] (12). All compounds 2-12 have been characterized by a combination of spectroscopic (IR, NMR) and crystallographic methods. All these clusters may be viewed as composed by a butterfly [Fe4C(CO)12]2? core bonded to Cu(I) fragments and/or H+ ions. 相似文献
93.
Alessandro D’Urso Giovanna Brancatelli Neal Hickey Erica Farnetti Rita De Zorzi Carmela Bonaccorso 《Supramolecular chemistry》2016,28(5-6):499-505
AbstractThe octaanionic 5,11,17,23-tetrasulfonato-25,26,27,28-tetrakis(hydroxycarbonylmethoxy)-calix[4]arene (cone conformation) (C4TsTc) was investigated as a sensor for the biogenic tetracationic polyamine, spermine .(H4Spe4+). Fluorescence titration experiments of the water-soluble calixarene with spermine showed the formation of the 2:1 and 1:1 calixarene:spermine complexes in solution. The single crystal X-ray diffraction analysis of [(NaC4TsTc)4·(H4Spe)7] confirmed the formation of 2:1 and 1:1 calixarene:spermine species and showed that the water-soluble calixarene binds the spermine either by partially hosting it in the inner cavity or through the carboxylate groups on the lower rim. In order to investigate the effect of multivalent systems, supramolecular assemblies of octaanionic calixarene molecules templated by meso-tetrakis(4-N-methylpyridyl)porphyrin (H2T4) in different stoichiometric porphyrin:calixarene ratios (1:4 and 3:4) were also tested for spermine binding in solution. Fluorescence titration experiments with the 1:4 and 3:4 H2T4:C4TsTc supramolecular complexes showed that the multivalent assemblies are more sensitive to the presence of spermine than the calixarene alone. 相似文献
94.
Femoni C Iapalucci MC Longoni G Tiozzo C Wolowska J Zacchini S Zazzaroni E 《Chemistry (Weinheim an der Bergstrasse, Germany)》2007,13(23):6544-6554
The synthesis, structure, spectroscopic characterization and electrical resistivity of the [EtV](2)[Fe(4)Pt(CO)(16)], [EtV][Fe(3)Pt(3)(CO)(15)].THF, [EtV][Fe(4)Au(CO)(16)](2)2.THF (EtV=1,1'-diethyl-4,4'-bipyridilium cation) and [NEt(4)](2)[Fe(4)Au(CO)(16)] is reported. The crystal structure of [EtV](2)[Fe(4)Pt(CO)(16)] is based on infinite stacks of [(EtV)(*+)](2) pi-dimers rotated by 90 degrees and isolated [Fe(4)Pt(CO)(16)](2-) ions. Within each pi-dimer, the [EtV](*+) radical ions are perfectly eclipsed and the distance between their mean planes is 3.275 A. The EPR spectrum of the solid material at room temperature clearly indicates the presence of a significantly populated triplet state of the pi-dimer, by showing signals both at Deltam=1 and Deltam=2. The solid-state structure of [EtV][Fe(3)Pt(3)(CO)(15)].THF is based on the ionic packing of [EtV](2+) and [Fe(3)Pt(3)(CO)(15)](2-) ions, inferred from a comparison of their molecular parameters with literature data. Significant electron transfer could have been expected to give [EtV](*+)[Fe(3)Pt(3)(CO)(15)](*-) on the basis of their formal redox potentials. In spite of their different stoichiometries, the structures of [EtV][Fe(4)Au(CO)(16)](2).2 THF and [NEt(4)](2)[Fe(4)Au(CO)(16)] both contain an isomer of the monoanion [Fe(4)Au(CO)(16)](-) in solution (previously characterized in the solid state as a [NMe(3)CH(2)Ph](2)[Fe(4)Au(CO)(16)]Cl mixed salt). Resistivity measurements on pellets of powdered samples of the above compounds indicate that their tetrasubstituted ammonium salts, and complex [EtV][Fe(4)Au(CO)(16)](2)2.THF, largely behave as insulators. However, the [EtV](2)[Fe(4)Pt(CO)(16)] and [EtV][Fe(3)Pt(3)(CO)(15)].THF samples respectively display resistivities 3 and 4 orders of magnitude less than those of their corresponding ammonium salts and could be classified as semiconductor materials. 相似文献
95.
Fiorella Di Nicuolo Roberta Castellani Alessandra De Cicco Nardone Greta Barbaro Carmela Paciullo Alfredo Pontecorvi Giovanni Scambia Nicoletta Di Simone 《Molecules (Basel, Switzerland)》2021,26(2)
Endometriosis is an estrogen-linked gynecological disease defined by the presence of endometrial tissue on extrauterine sites where it forms invasive lesions. Alterations in estrogen-mediated cellular signaling seems to have an essential role in the pathogenesis of endometriosis. Higher estrogen receptor (ER)-β levels and enhanced ER-β activity were detected in endometriotic tissues. It is well known that ER-β interacts with components of the cytoplasmic inflammasome-3 (NALP-3), the NALP-3 activation increases interleukin (IL)-1β and IL-18, enhancing cellular adhesion and proliferation. Otherwise, the inhibition of ER-β activity suppresses the ectopic lesions growth. The present study aims to investigate the potential effect of α-lipoic acid (ALA) on NALP-3 and ER-β expression using a western blot analysis, NALP-3-induced cytokines production by ELISA, migration and invasion of immortalized epithelial (12Z) and stromal endometriotic cells (22B) using a 3D culture invasion assay, and matrix-metalloprotease (MMPs) activity using gelatin zymography. ALA significantly reduces ER-β, NALP-3 protein expression/activity and the secretion of IL-1β and IL-18 in both 12Z and 22B cells. ALA treatment reduces cellular adhesion and invasion via a lower expression of adhesion molecules and MMPs activities. These results provide convincing evidence that ALA might inhibit endometriosis progression. 相似文献
96.
Cristiana Cesari Beatrice Berti Francesco Calcagno Cristina Femoni Marco Garavelli Maria Carmela Iapalucci Ivan Rivalta Stefano Zacchini 《Molecules (Basel, Switzerland)》2021,26(6)
The reaction of [Co(CO)4]− (1) with M(I) compounds (M = Cu, Ag, Au) was reinvestigated unraveling an unprecedented case of polymerization isomerism. Thus, as previously reported, the trinuclear clusters [M{Co(CO)4}2]− (M = Cu, 2; Ag, 3; Au, 4) were obtained by reacting 1 with M(I) in a 2:1 molar ratio. Their molecular structures were corroborated by single-crystal X-ray diffraction (SC-XRD) on isomorphous [NEt4][M{Co(CO)4}2] salts. [NEt4](3)represented the first structural characterization of 3. More interestingly, changing the crystallization conditions of solutions of 3, the hexanuclear cluster [Ag2{Co(CO)4}4]2− (5) was obtained in the solid state instead of 3. Its molecular structure was determined by SC-XRD as Na2(5)·C4H6O2, [PPN]2(5)·C5H12 (PPN = N(PPh3)2]+), [NBu4]2(5) and [NMe4]2(5) salts. 5 may be viewed as a dimer of 3 and, thus, it represents a rare case of polymerization isomerism (that is, two compounds having the same elemental composition but different molecular weights) in cluster chemistry. The phenomenon was further studied in solution by IR and ESI-MS measurements and theoretically investigated by computational methods. Both experimental evidence and density functional theory (DFT) calculations clearly pointed out that the dimerization process occurs in the solid state only in the case of Ag, whereas Cu and Au related species exist only as monomers. 相似文献
97.
Domenico Iacopetta Alessia Catalano Jessica Ceramella Carmela Saturnino Lara Salvagno Ileana Ielo Dario Drommi Elisabetta Scali Maria Rosaria Plutino Giuseppe Rosace Maria Stefania Sinicropi 《Molecules (Basel, Switzerland)》2021,26(9)
In the late 1930s and early 1940s, it was discovered that the substitution on aromatic rings of hydrogen atoms with chlorine yielded a novel chemistry of antimicrobials. However, within a few years, many of these compounds and formulations showed adverse effects, including human toxicity, ecotoxicity, and unwanted environmental persistence and bioaccumulation, quickly leading to regulatory bans and phase-outs. Among these, the triclocarban, a polychlorinated aromatic antimicrobial agent, was employed as a major ingredient of toys, clothing, food packaging materials, food industry floors, medical supplies, and especially of personal care products, such as soaps, toothpaste, and shampoo. Triclocarban has been widely used for over 50 years, but only recently some concerns were raised about its endocrine disruptive properties. In September 2016, the U.S. Food and Drug Administration banned its use in over-the-counter hand and body washes because of its toxicity. The withdrawal of triclocarban has prompted the efforts to search for new antimicrobial compounds and several analogues of triclocarban have also been studied. In this review, an examination of different facets of triclocarban and its analogues will be analyzed. 相似文献
98.
Pierpaolo D’Urso Riccardo Massari Livia De Giovanni Carmela Cappelli 《Fuzzy Optimization and Decision Making》2017,16(1):51-70
In several real life and research situations data are collected in the form of intervals, the so called interval-valued data. In this paper a fuzzy clustering method to analyse interval-valued data is presented. In particular, we address the problem of interval-valued data corrupted by outliers and noise. In order to cope with the presence of outliers we propose to employ a robust metric based on the exponential distance in the framework of the Fuzzy C-medoids clustering mode, the Fuzzy C-medoids clustering model for interval-valued data with exponential distance. The exponential distance assigns small weights to outliers and larger weights to those points that are more compact in the data set, thus neutralizing the effect of the presence of anomalous interval-valued data. Simulation results pertaining to the behaviour of the proposed approach as well as two empirical applications are provided in order to illustrate the practical usefulness of the proposed method. 相似文献
99.
Valeria Visalli Carolina Muscoli Iolanda Sacco Francesca Sculco Ernesto Palma Nicola Costa Carmela Colica Domenicantonio Rotiroti Vincenzo Mollace 《BMC neuroscience》2007,8(1):106
Background
HIV envelope gp 120 glycoprotein is released during active HIV infection of brain macrophages thereby generating inflammation and oxidative stress which contribute to the development of the AIDS-Dementia Complex (ADC). Gp120 has also been found capable to generate excitotoxic effect on brain tissue via enhancement of glutamatergic neurotransmission, leading to neuronal and astroglial damage, though the mechanism is still to be better understood. 相似文献100.
Francesca Buiarelli Patrizia Di Filippo Carmela Riccardi Donatella Pomata Eugenio Rumolo Luigi Giannetti 《International journal of environmental analytical chemistry》2015,95(8):713-729
An effective analytical method for the screening of mycotoxins, in indoor/outdoor airborne particulate matter, was developed and method performance data are presented. Mycotoxins are natural compounds produced, in particular conditions, as secondary metabolites by filamentous fungi and moulds, and, after their production, they can be transported far from their source. To simulate real samples, an urban dust (reference material 1649a) free from mycotoxins was used as matrix and spiked by the most common mycotoxins, chosen on the basis of studies carried out previously in other real matrices: deoxynivalenol, aflatoxin B1, ochratoxin A, T-2 toxin, zearalenone and sterigmatocystin. The analytical method was optimised and structured in four successive steps: (1) accelerated solvent extraction of the (spiked) analytes from matrix, (2) solid-phase purification (SPE) of the previous extract, (3) pre-concentration of the eluates from SPE and (4) analysis of the concentrated eluates by high performance liquid chromatography tandem mass spectrometry in multiple reaction monitoring mode. After a proper sampling campaign, the method was applied to real indoor and outdoor particulate matter samples, where the clean-up step showed to be very effective and fundamental to avoid misleading analytical results. 相似文献