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31.
Nonlinear Dynamics - An integrable extension of the Kadomtsev–Petviashvili (KP) and Davey–Stewartson (DS) equations is investigated in this paper. We will refer to this integrable... 相似文献
32.
Raluca Pele Gabriel Marc Anca Stana Ioana Ionu Cristina Nastas Brîndua Tiperciuc Ilioara Oniga Adrian Pîrnu Laurian Vlase Ovidiu Oniga 《Molecules (Basel, Switzerland)》2022,27(8)
Considering the important damage caused by the reactive oxygen (ROS) and nitrogen (RNS) species in the human organism, the need for new therapeutic agents, with superior efficacy to the known natural and synthetic antioxidants, is crucial. Quinazolin-4-ones are known for their wide range of biological activities, and phenolic compounds display an important antioxidant effect. Linking the two active pharmacophores may lead to an increase of the antioxidant activity. Therefore, we synthesized four series of new hybrid molecules bearing the quinazolin-4-one and phenol scaffolds. Their antioxidant potential was evaluated in vitro, considering different possible mechanisms of action: hydrogen atom transfer, ability to donate electrons and metal ions chelation. Theoretical quantum and thermodynamical calculations were also performed. Some compounds, especially the ortho diphenolic ones, exerted a stronger antioxidant effect than ascorbic acid and Trolox. 相似文献
33.
Anca Corina Frca Sonia Ancua Socaci Maria Simona Chi Francisc Vasile Dulf Paula Podea Maria Tofan 《Molecules (Basel, Switzerland)》2022,27(6)
Apple industrial by-products are a promising source of bioactive compounds with direct implications on human health. The main goal of the present work was to characterize the Jonathan and Golden Delicious by-products from their fatty acid, amino acid, and volatile aroma compounds’ point of view. GC-MS (gas chromatography-mass spectrometry) and ITEX/GC-MS methods were used for the by-products characterization. Linoleic and oleic were the main fatty acids identified in all samples, while palmitic and stearic acid were the representant of saturated ones. With respect to amino acids, from the essential group, isoleucine was the majority compound identified in JS (Jonathan skin) and GS (Golden skin) samples, lysine was the representant of JP (Jonathan pomace), and valine was mainly identified in GP (Golden pomace). A total number of 47 aroma volatile compounds were quantified in all samples, from which the esters groups ranged from 41.55–53.29%, aldehydes 29.75–43.99%, alcohols from 4.15 to 6.37%, ketones 4.14–5.72%, and the terpenes and terpenoids group reached values between 2.27% and 4.61%. Moreover, the by-products were valorized in biscuits manufacturing, highlighting their importance in enhancing the volatile aroma compounds, color, and sensorial analysis of the final baked goods. 相似文献
34.
An analysis of experimental data for ternary copolymerizations has been performed by an optimizing calculation method, resulting in the estimation of the r ij copolymerization constants. The azeotrope calculation results have been compared to those based on the r ij constants found for binary copolymerization. For each set of r ij constants, the possibility of the ternary azeotropy was studied. The formation of quasihomogeneous ternary copolymers was studied subsequent to the determination of the ternary pseudoazeotropy domains occurring at the intersection of the partial pseudoazeotropy domains. 相似文献
35.
Xiao-Jun Yang Feng Gao J. A. Tenreiro Machado Dumitru Baleanu 《The European physical journal. Special topics》2017,226(16-18):3567-3575
In this paper, a new fractional derivative involving the normalized sinc function without singular kernel is proposed. The Laplace transform is used to find the analytical solution of the anomalous heat-diffusion problems. The comparative results between classical and fractional-order operators are presented. The results are significant in the analysis of one-dimensional anomalous heat-transfer problems. 相似文献
36.
Advances on the Determination of the Astatine Pourbaix Diagram: Predomination of AtO(OH)2− over At− in Basic Conditions
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Dumitru‐Claudiu Sergentu Dr. David Teze Dr. Andréa Sabatié‐Gogova Dr. Cyrille Alliot Ning Guo Dr. Fadel Bassal Dr. Isidro Da Silva Prof. Dr. David Deniaud Dr. Rémi Maurice Dr. Julie Champion Dr. Nicolas Galland Dr. Gilles Montavon 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(9):2964-2971
It is generally assumed that astatide (At?) is the predominant astatine species in basic aqueous media. This assumption is questioned in non‐complexing and non‐reductive aqueous solutions by means of high‐pressure anion‐exchange chromatography. Contrary to what is usually believed, astatide is found to be a minor species at pH=11. A different species, which also bears a single negative charge, becomes predominant when the pH is increased beyond 7. Using competition experiments, an equilibrium constant value of 10?6.9 has been determined for the formation of this species from AtO(OH) with the exchange of one proton. The identification of this species, AtO(OH)2?, is achieved through relativistic quantum mechanical calculations, which rule out the significant formation of the AtO2? species, while leading to a hydrolysis constant of AtO(OH) in excellent agreement with experiment when the AtO(OH)2? species is considered. Beyond the completion of the Pourbaix diagram of astatine, this new information is of interest for the development of 211At radiolabeling protocols. 相似文献
37.
We consider the single-inclusive minijet cross section in pA at forward rapidity within the color glass condensate model of high energy collisions. We show that the nucleus appears black to the incident quarks except for very large impact parameters. A markedly flatter p(t) distribution as compared to QCD in the dilute perturbative limit is predicted for transverse momenta about the saturation scale, which could be as large as Q(2)(s) approximately 10 GeV2 for a gold nucleus boosted to rapidity approximately 10 (as at the BNL-RHIC). 相似文献
38.
39.
We put forward a mechanism for tailoring, and even arresting, the collapse of wave packets in nonlinear media, whose dynamics is governed by nonlocal two-dimensional nonlinear Schr?dinger-like equations. The key ingredient of the scheme is the self-generation of nonlocal nonlinearities mediated by wave rectification. 相似文献
40.
Dumitru Vălcan 《Czechoslovak Mathematical Journal》2003,53(2):277-287
The present work gives some characterizations of R-modules with the direct summand sum property (in short DSSP), that is of those R-modules for which the sum of any two direct summands, so the submodule generated by their union, is a direct summand, too. General results and results concerning certain classes of R-modules (injective or projective) with this property, over several rings, are presented. 相似文献