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391.
392.
Giovanna Barbarella Pasquale Dembech Anna Garbesi Antonino Fava 《Magnetic resonance in chemistry : MRC》1976,8(9):469-476
13C n.m.r. spectra of methyl substituted thianes and thianium cations have been determined. The magnitude of the 13C substituent effects of an equatorial methyl group or of a gem-dimethyl grouping appear to depend in a systematic way on whether the carbon atom concerned is adjacent to, or removed from, the heteroatom. The shieldings are discussed in relation to the conformational properties of the thiane ring. Moreover, the average 13C substituent parameters obtained from conformationally biased systems are applied to potentially mobile systems to assess the position of the conformational equilibrium. 相似文献
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396.
Andrea Clementi Pierluigi Crescenzi Carola Doerr Pierre Fraigniaud Francesco Pasquale Riccardo Silvestri 《Random Structures and Algorithms》2016,48(2):290-312
We analyze randomized broadcast in dynamic networks modeled as edge‐Markovian evolving graphs. The most realistic range of edge‐Markovian parameters yields sparse and disconnected graphs. We prove that, in this setting, the “push” protocol completes with high probability in optimal logarithmic time. © 2015 Wiley Periodicals, Inc. Random Struct. Alg., 48, 290–312, 2016 相似文献
397.
Vincenzo Leone Pasquale Iovino Sante Capasso Marco Trifuoggi Dino Musmarra 《Chemical Papers》2018,72(4):929-935
New environmental friendly sorption materials were synthesized and studied to remove organic contaminants in wastewater purification. Humic acids extracted from green-waste compost (HAcomp) and from leonardite (HAleo) were chemically characterized by infrared spectroscopy, carbon nitrogen and hydrogen analysis, ash content, hydrophobicity tests, and molecular weight distribution. Humic acids were thermally immobilized at 330 °C for 1.5 h and their sorbent properties towards of some benzene derivatives (toluene, o-xylene, phenol, and benzyl alcohol) with the batch equilibrium method were studied. HAcomp was found to be less rich in aromatic rings and more hydrophobic than HAleo. The maximum amount of sorbate bound at the equilibrium was consistently higher for the immobilized HA from compost than from leonardite and increased with the n-octanol/water partition coefficient of the adsorbate. The data point to hydrophobic interactions as the main force involved in the sorption of the compounds tested. The results showed that these materials can have potential applications in wastewater purification. 相似文献
398.
Ralph J. De Pasquale 《Journal of fluorine chemistry》1976,8(4):311-321
-Phenylisocyanate reacts with cyclic or linear anhydrides with the aid of catalysts to form -(N-arylimides) in good yields. Similar reactions with fluorinated acids lead directly to amides. This isocyanate undergoes smooth reaction with various substrates (hexafluoroacetone, trioctylphospine oxide, and itself). Several reactions between -aryl and -alkyl isocyanates are compared. Reaction between the latter and -anhydrides or acids gives products derived from fluoride ion transfer reactions. 相似文献
399.
Mura P Camalli M Messori L Piccioli F Zanello P Corsini M 《Inorganic chemistry》2004,43(13):3863-3870
Two ruthenium(III) complexes bearing the thiazole ligand, namely, thiazolium (bisthiazole) tetrachlororuthenate (I, TzICR) and thiazolium (thiazole, DMSO) tetrachlororuthenate (II, TzNAMI) were prepared and characterized. The crystal structures of both complexes were solved by X-ray diffraction methods and found to match closely those of the corresponding imidazole complexes. The behavior in aqueous solution of bothTzICR and TzNAMI was analyzed spectroscopically. The time-dependent spectrophotometric profiles resemble closely those of the related ICR and NAMI-A anticancer compounds, respectively. It is observed that replacement of imidazole with thiazole, a less basic ligand, produces a significant decrease of the ligand exchange rates in the case of the NAMI-like compound. The main electrochemical features of these ruthenium(III) thiazole complexes were determined and compared to those of ICR and NAMI-A. Moreover, some preliminary data were obtained on their biological properties. Notably, both complexes exhibit higher reactivity toward serum albumin than toward calf thymus DNA; cytotoxicity is negligible in line with expectations. A more extensive characterization of the pharmacological properties in vivo is presently in progress. 相似文献
400.
A reaction scheme for propylene formation from methyl alcohol over ZSM-5-based catalysts is proposed which involves two vicinal acidic-basic sites.
ZSM-5. - - .相似文献