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81.
Merlin C. E. Bandeira César V. Franco Emilse Martini 《Journal of Solid State Electrochemistry》1999,3(4):210-214
The present study focuses on the electronic and electrochemical features of a copolymer electrochemically grown from pyrrole
and trans-[RuCl2(pmp)4] monomers, where pmp = 3-(pyrrol-1-ylmethyl)pyridine. The results from electrochemical impedance spectroscopy analyses revealed
the redox behavior of the poly{pyrrole-trans-[RuCl2(pmp)4]} compound as well as the non-homogeneous nature of the extremely thin polymeric layers. An equivalent circuit is proposed
for an optimized film produced under the scope of the work.
Received: 4 May 1998 / Accepted: 24 August 1998 相似文献
82.
Emission of volatile sesquiterpenes and monoterpenes in grapevine genotypes following Plasmopara viticola inoculation in vitro 下载免费PDF全文
Alberto Algarra Alarcon Valentina Lazazzara Luca Cappellin Pier Luigi Bianchedi Rainer Schuhmacher Georg Wohlfahrt Ilaria Pertot Franco Biasioli Michele Perazzolli 《Journal of mass spectrometry : JMS》2015,50(8):1013-1022
The grapevine (Vitis vinifera) is one of the most widely cultivated fruit crops globally, and one of its most important diseases in terms of economic losses is downy mildew, caused by Plasmopara viticola. Several wild Vitis species have been found to be resistant to this pathogen and have been used in breeding programs to introduce resistance traits to susceptible cultivars. Plant defense is based on different mechanisms, and volatile organic compounds (VOCs) play a major role in the response to insects and pathogens. Although grapevine resistance mechanisms and the production of secondary metabolites have been widely characterized in resistant genotypes, the emission of VOCs has not yet been investigated following P. viticola inoculation. A Proton Transfer Reaction‐Time of Flight‐Mass Spectrometer (PTR‐ToF‐MS) was used to analyze the VOCs emitted by in vitro‐grown plants of grapevine genotypes with different levels of resistance. Downy mildew inoculation significantly increased the emission of monoterpenes and sesquiterpenes by the resistant SO4 and Kober 5BB genotypes, but not by the susceptible V. vinifera Pinot noir. Volatile terpenes were implicated in plant defense responses against pathogens, suggesting that they could play a major role in the resistance against downy mildew by direct toxicity or by inducing grapevine resistance. The grapevine genotypes differed in terms of the VOC emission pattern of both inoculated and uninoculated plants, indicating that PTR‐ToF‐MS could be used to screen hybrids with different levels of downy mildew resistance. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
83.
Kobra Mahdavipour Mahshid Khazaei Shadfar Hossein Rangani Jahromi Roberto Morandotti Rosario Lo Franco 《Entropy (Basel, Switzerland)》2022,24(3)
A witness of non-Markovianity based on the Hilbert–Schmidt speed (HSS), a special type of quantum statistical speed, has been recently introduced for low-dimensional quantum systems. Such a non-Markovianity witness is particularly useful, being easily computable since no diagonalization of the system density matrix is required. We investigate the sensitivity of this HSS-based witness to detect non-Markovianity in various high-dimensional and multipartite open quantum systems with finite Hilbert spaces. We find that the time behaviors of the HSS-based witness are always in agreement with those of quantum negativity or quantum correlation measure. These results show that the HSS-based witness is a faithful identifier of the memory effects appearing in the quantum evolution of a high-dimensional system with a finite Hilbert space. 相似文献
84.
R. Lo Franco G. Compagno A. Messina A. Napoli 《The European physical journal. Special topics》2008,160(1):247-257
We show that the N-photon generalized binomial states of electromagnetic field may be put in a bijective mapping with the
coherent atomic states of N two-level atoms. We exploit this correspondence to simply obtain both known and new properties
of the N-photon generalized binomial states. In particular, an over-complete basis of these binomial states and an orthonormal
basis are obtained. Finally, the squeezing properties of generalized binomial state are analyzed. 相似文献
85.
A tridentate Schiff base ligand, (E)‐3‐((2‐hydroxy‐3‐methoxybenzylidene)amino)‐2‐methylquinazolin‐4(3H)‐one [HL], and its mixed‐ligand Ni(II) complex [Ni(L)(imi)], were synthesized and fully characterized using elemental analysis, FT‐IR, UV–Vis and 1HNMR spectroscopy techniques. The structure of the synthesized ligand and complex was determined with single crystal X‐ray diffraction method. In the complex, a square planner geometry was observed around the Ni(II) central atom coordinated with the donor atoms of the Schiff base ligand and one nitrogen of imidazole group. In addition, the catalytic activity of the complex on the three‐component condensation of hydrazine hydrate with phthalic anhydride and dimedone to obtain 2H–indazolo[2,1‐b]phthalazine‐triones was investigated. Furthermore, in‐vitro antimicrobial studies were performed that indicated the great antibacterial activities of the Ni(II) complex against Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa and Bacillus cereus bacteria. 相似文献
86.
Edoardo Longo Ksenia Morozova Sine Yener Emanuele Boselli Franco Biasioli Matteo Scampicchio 《Journal of mass spectrometry : JMS》2019,54(5):412-421
This work proposes a novel method for the direct flow injection profiling of acylglycerols in edible oils and fats without preliminary extraction and consequent reconstitution in the injection solvent. The work exploits the outstanding performance of high‐resolution mass spectrometry to target unique elemental compositions even in the most complex matrices. The performance of isopropanol as the unique solvent for both the solubilization and analysis of acylglycerols was investigated in comparison with other classical methods involving preliminary extractions, sample recovery, and analysis. The calibrations of two triglyceride standards (triolein and trilinolenin) were successfully performed in presence and absence of oil matrix. As final application, the effects on the acylglycerol fraction of a heat treatment on three different fat samples (extra virgin olive oil, lard oil, and fat from dry cured ham—speck) were monitored. The proposed method is therefore suitable for a rapid evaluation of acylglycerol fractions in food lipid samples. 相似文献
87.
Pedro Henrique Cavalcanti Franco Saulo Fehelberg Pinto Braga Renata Barbosa de Oliveira Isabela Costa César 《Magnetic resonance in chemistry : MRC》2020,58(1):97-105
Quantitative nuclear magnetic resonance (qNMR) is an analytical technique that offers numerous advantages in pharmaceutical applications including minimum sample preparation and rapid data collection times with no need for response factor corrections, being a powerful tool for assaying drug content in both drug discovery and early drug development. In the present work, we have applied qNMR, using both the internal standard and the electronic reference to access in vivo concentrations 2 calibration methods, to assess the purity of RI76, a novel antifungal drug candidate. NMR acquisition and processing parameters were optimized in order to obtain spectra with intense, well-resolved signals of completely relaxed nuclei. The analytical method was validated following current guidelines, demonstrating selectivity, linearity, accuracy, precision, and robustness. The calibration approaches were statistically compared, and no significant difference was observed when comparing the obtained results and their dispersion in terms of relative standard deviation. The proposed qNMR method may, therefore, be used for both qualitative and quantitative assessments of RI76 in early drug development and for characterization of this compound. 相似文献
88.
Denis Bonheure Patrick Habets Franco Obersnel Pierpaolo Omari 《Journal of Differential Equations》2007,243(2):208-237
We discuss existence and multiplicity of positive solutions of the one-dimensional prescribed curvature problem depending on the behaviour at the origin and at infinity of the potential . Besides solutions in W2,1(0,1), we also consider solutions in which are possibly discontinuous at the endpoints of [0,1]. Our approach is essentially variational and is based on a regularization of the action functional associated with the curvature problem. 相似文献
89.
90.
Summary We prove the existence of martingale solutions and of stationary solutions of stochastic Navier-Stokes equations under very general hypotheses on the diffusion term. The stationary martingale solutions yield the existence of invariant measures, when the transition semigroup is well defined. The results are obtained by a new method of compactness. 相似文献