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101.
Vittorio Colao Giuseppe Marino Luigi Muglia 《Applied mathematics and computation》2012,218(11):6232-6241
Starting by a finite family of mappings, we define the concept of procedure with Lipschitzian dependence of the coefficients. We give seven concrete examples of such procedures and prove the strong convergence of two viscosity methods. 相似文献
102.
Cosimo Taiti Elisa Masi Vittoria Cicaloni Vittorio Vinciguerra Laura Salvini Stefania Garzoli 《Molecules (Basel, Switzerland)》2022,27(24)
Considering the large number of volatile molecules that characterize Cannabis sativa L., adequate investigation supported by the application of robust and effective analytical methods is essential to better understand the impact of these low- and medium-molecular-weight molecules on the entire phytocomplex. This work aimed to characterize the volatile fraction of the chemical profile of three different cultivars of Cannabis sativa L. pollen, grown in Italy, which were thoroughly investigated by the application of two complementary techniques: SPME-GC-MS and PTR-ToF-MS. Furthermore, in order to provide more information on the chemical profile of the matrices under study, the cannabinoid content of the hexane extracts was also measured by GC-MS. Until now, no similar study, in terms of survey techniques applied, has been performed on C. sativa pollen. The obtained results showed a high content of volatile molecules, which differentiated the three matrices. The data relating to the content of cannabinoids were also interesting as they showed that one of the three cultivars was richer than the others. Finally, an in-depth statistical survey was performed to better compare the investigated samples and identify the molecules that most contribute to differentiating them. The findings of this study may be useful for integrating the compositional information on C. sativa L. 相似文献
103.
Silvia Gentiluomo Dr. Sanjay B. Thorat Dr. Antonio Esau Del Río Castillo Dr. Peter S. Toth Dr. Jaya Kumar Panda Dr. Vittorio Pellegrini Dr. Francesco Bonaccorso 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(29):6715-6725
One of the applications of graphene in which its scalable production is of utmost importance is the development of polymer composites. Among the techniques used to produce graphene flakes, the liquid-phase exfoliation (LPE) of graphite stands out due to its versatility and scalability. However, solvents suitable for the LPE process are generally toxic and have a high boiling point, making the processing challenging. The use of low boiling point solvents could be convenient for the processing, due to the easiness of their removal. In this study, the use of poly(methyl methacrylate) (PMMA) as a stabilizing agent is proposed for the production of graphene flakes in a low boiling point solvent, that is, acetone. The graphene dispersions produced in the mixture acetone-PMMA have higher concentration, +175 %, and contain a higher percentage of few-layer graphene flakes (<5 layers), that is, +60 %, compared to the dispersions prepared in acetone. The as-produced graphene dispersions are used to develop graphene/acrylonitrile-butadiene-styrene composites. The mechanical properties of the pristine polymer are improved, that is, +22 % in the Young's modulus, by adding 0.01 wt. % of graphene flakes. Moreover, a decrease of ≈20 % in the oxygen permeability is obtained by using 0.1 wt. % of graphene flakes filler, compared to the unloaded matrix. 相似文献
104.
Pier Vittorio Ceccherini 《Results in Mathematics》1997,32(3-4):221-233
105.
Jochen Bartels Vittorio Del Duca Mark Wüsthoff 《Zeitschrift fur Physik C Particles and Fields》1997,76(1):75-79
As a signal for the BFKL Pomeron in small-x deep inelastic ep scattering, we calculate the azimuthal dependence of the inclusive cross section of forward jets relative to the outgoing electron. For not very large differences in rapidity between the current jet and the forward jet the cross section peaks at π/2. For increasing rapidity BFKL dynamics predicts a decorrelation in the azimuthal dependence between the electron and the forward jet. 相似文献
106.
107.
Exploiting Synergistic Effects in Organozinc Chemistry for Direct Stereoselective C‐Glycosylation Reactions at Room Temperature 下载免费PDF全文
Dr. Alberto Hernán‐Gómez Dr. Samantha A. Orr Dr. Marina Uzelac Dr. Alan R. Kennedy Dr. Santiago Barroso Dr. Xavier Jusseau Dr. Sébastien Lemaire Dr. Vittorio Farina Prof. Eva Hevia 《Angewandte Chemie (International ed. in English)》2018,57(33):10630-10634
Pairing a range of bis(aryl) zinc reagents ZnAr2 with the stronger Lewis acidic [(ZnArF2)] (ArF=C6F5), enables highly stereoselective cross‐coupling between glycosyl bromides and ZnAr2 without the use of a transition metal. Reactions occur at room temperature with excellent levels of stereoselectivity, where ZnArF2 acts as a non‐coupling partner although its presence is crucial for the execution of the C(sp2)–C(sp3) bond formation process. Mechanistic studies have uncovered a unique synergistic partnership between the two zinc reagents, which circumvents the need for transition‐metal catalysis or forcing reaction conditions. Key to the success of the coupling is the avoidance of solvents that act as Lewis bases versus diarylzinc compounds (e.g. THF). 相似文献
108.
Recently the low-energy effective string theory has been used by Gasperini and Veneziano to elaborate a very interesting scenario for the early history of the universe (birth of the universe as quantum scattering). Here we investigate the gauge fixing and the problem of the definition of a global time parameter for the quantum form of the model, and obtain the positive norm Hilbert space of states. 相似文献
109.
α-bromo Michael acceptors undergo ipso-substitution by phenol or benzenethiol in the K2CO3-acetone system, the reaction originating the (Z) isomers, via a stereospecific AdSNE process. 相似文献
110.
Vittorio Lucchini Maurizio Prato Gianfranco Scorrano Paolo Tecilla 《Journal of heterocyclic chemistry》1986,23(4):1135-1139
Substituted 4-benzoyl-3a,4,5,9b-tetrahydro-3H-cyclopenta[c]quinolines 3 and 6-benzoyl-5,6,6a,7,8,10a-hexahydrophenanthridines 10 are obtained through Lewis acid catalyzed addition of 1-phenyl-2-arylamino-2-methoxyethanones 2 to cyclopentadienes and 1,3-cyclohexadiene respectively. Compounds 3 can be converted to the aromatized analogues by reaction with 2,3-dichloro-5,6-dicyanobenzoquinone in refluxing benzene. Compounds 10 are oxidized by sulfur either in decalin or in quinoline to substituted 6-benzoylphenanthridines. 相似文献