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1.
Superperiodicity, chaos and coexisting orbits of ion-acoustic waves (IAWs) are studied in a multi-component plasma consisting of fluid ions, q -nonextensive cold and hot electrons and Maxwellian hot positrons. The significant impacts of the system parameters on superperiodic and nonlinear periodic IAWs are presented. Considering an external periodic perturbation various types of quasiperiodic and chaotic features for IAWs are studied in different parametric ranges through time series’ plots, phase spaces and Lyapunov exponents. It has been observed that there exist some coexisting orbits for IAWs. Coexisting orbits for IAWs in a classical electron–positron–ion plasma system are reported. 相似文献
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Rafael Dias do Espírito Santo Rosineide Costa Simas Alviclér Magalhães Vanessa Gonçalves dos Santos Thais Regiani Ana Cristina Isler Natiza Graziele Martins Marcos Nogueira Eberlin Eduardo René Pérez González 《Journal of Physical Organic Chemistry》2013,26(4):315-321
Molecules containing the guanidinic nuclei possess several pharmacological applications, and knowing the preferred isomers of a potential drug is important to understand the way it operates pharmacologically. Benzoylguanidines were synthesized in satisfactory to good yields and characterized by NMR, Electrospray Ionization Mass Spectrometry (ESI‐MS) and Fourrier Transform InfraRed Spectroscopy techniques (FTIR). E/Z isomerism of the guanidines was studied and confirmed by NMR analysis in solution (1H‐13C Heteronuclear Single Quantum Coherence (HSQC) and Heteronuclear Multiple‐Bond Correlation (HMBC), 1H‐15N HMBC, 1H‐1H Correlation Spectroscopy (COSY) and Nuclear Overhauser Effect Spectroscopy (NOESY) experiments) at low temperatures. Compounds with p‐Cl and p‐Br aniline moiety exist mainly as Z isomer with a small proportion of E isomer, whereas compounds with p‐NO2 moiety showed a decrease in proportion of isomer Z. The results are important for the application of these molecules as enzymatic inhibitors. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
3.
Easwaramoorthy D. Gowrisankar A. Manimaran A. Nandhini S. Rondoni Lamberto Banerjee Santo 《Nonlinear dynamics》2021,106(2):1375-1395
Nonlinear Dynamics - The coronavirus disease 2019 (COVID-19) pandemic has fatalized 216 countries across the world and has claimed the lives of millions of people globally. Researches are being... 相似文献
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Condensation of 2-nitrothiophenol with ethyl propiolate afforded 3-(2-nitrophenylthio)propenoate. Oxidation of sulfur atom to sulfone group gave ethyl 3-(2-nitrophenylsulfonyl)propenoate, which underwent condensation with tosyl methylisocyanide (TosMIC) to yield ethyl 4-(2-nitrophenylsulfonyl)pyrrole-3-carboxylate. Reduction of nitro group afforded ethyl 4-(2-aminophenylsulfonyl)-1H-pyrrole-3-carboxylate, which was cyclized to 2H-pyrrolo[3,4-b][1,5] benzothiazepin-10(9H)-one 4,4-dioxide. Similar procedure was used for the synthesis of 9,10-dihydro-10-methyl-2H-pyrrolo[3,4-b][1,5]benzothiazepine 4,4-dioxide. 相似文献
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P. M. Ossi F. Neri N. Santo S. Trusso 《Applied Physics A: Materials Science & Processing》2011,104(3):829-837
Silver and gold thin films were deposited by pulsed laser ablation in a controlled Ar atmosphere at pressures between 10 and
100 Pa. Different morphologies, ranging from isolated nanoparticle arrays up to nanostructured thin films were observed. Fast
imaging of the plasma allowed deducing the expansion dynamics of the ablated plume. Plasma velocity and volume were used together
with the measured average ablated mass per pulse as input parameters in a model to estimate the average size of nanoparticles
grown in the plume. The nanoparticle size is expected to decrease from 4 nm down to 1 nm with decreasing Ar pressure between
100 and 10 Pa: this was confirmed by transmission electron micrographs which indicate a reduced dispersion of particle size
over narrow size ranges. The production of substrates for surface enhanced Raman scattering whose performances critically
depend on nanoparticle size, shape, and structure is discussed. 相似文献
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After our article, Physica A 391 (2012) 107–112, had been published online, T. Hillen told us about a theorem by Osaki, relevant for our numerical simulations. 相似文献
10.
Archimede Rotondo Giuseppe Bruno Francesco Nicol Giuseppe Tresoldi Santo Di Pietro 《Acta Crystallographica. Section C, Structural Chemistry》2010,66(1):o15-o19
The structure of 2,6‐bis(2‐pyridyltsulfanylmethyl)pyridine (pytmp), (I), C17H15N3S2, presents a twisted conformation, with the three planar moieties almost perpendicular to each other. The structures of two related derivatives, namely 2,6‐bis(6‐methyl‐2‐pyridylsulfanylmethyl)pyridine (mpytmp), (II), C19H19N3S2, and 2,6‐bis(4‐methyl‐2‐pyrimidylsulfanylmethyl)pyridine (mprtmp) n‐pentane hemisolvate, (III), C17H17N5S2·0.5C5H12, present extended planar fragments with just one quasi‐perpendicular arylsulfanylmethyl side arm, such that the molecules are folded in an L‐shaped conformation. All three conformations appear different from those adopted by similar compounds, demonstrating the great flexibility of such species, although such differences in conformational behaviour might drive specific coordination modes. 相似文献