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121.
Mehrzia Krimi Ammar Fatma Ben Amor Tahar Jouini Ahmed Driss 《Journal of chemical crystallography》2002,32(3-4):87-89
The synthesis and crystal structure of a new dinuclear complex Cu2(C2H4N4)2 (CH3N3)4 are reported. It crystallizes in the monoclinic system of space group P21/c, with a = 8,459(1) Å, b = 15,481(3) Å, c = 8,714(2) Å, = 110,60(1)°, and Z = 2. The centrosymmetric molecular structure of Cu2(C2H4N4)2(CH3N3)4 comprises a tetrakis(guanidino)-bridged dinuclear copper(II) core with axially located cnge moities. 相似文献
122.
A Topochemical Approach to Synthesize Layered Materials Based on the Redox Reactivity of Anionic Chalcogen Dimers
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Dr. Shunsuke Sasaki Dr. Dalel Driss Elodie Grange Dr. Jean‐Yves Mevellec Dr. Maria Teresa Caldes Dr. Catherine Guillot‐Deudon Dr. Sylvian Cadars Dr. Benoît Corraze Dr. Etienne Janod Dr. Stéphane Jobic Dr. Laurent Cario 《Angewandte Chemie (International ed. in English)》2018,57(41):13618-13623
Layered transition metal compounds represent a major playground to explore unconventional electric or magnetic properties. In that framework, topochemical approaches that mostly preserve the topology of layered reactants have been intensively investigated to tune properties and/or design new materials. Topochemical reactions often involve the insertion or deinsertion of a chemical element accompanied by a change of oxidation state of the cations only. Conversely, cases where anions play the role of redox centers are very scarce. Here we show that the insertion of copper into two dimensional precursors containing chalcogen dimers (Q2)2? (Q=S, Se) can produce layered materials with extended (CuQ) sheets. The reality of this topochemical reaction is demonstrated here for different pristine materials, namely La2O2S2, Ba2F2S2, and LaSe2. Therefore, this work opens up a new synthetic strategy to design layered transition metal compounds from precursors containing polyanionic redox centers. 相似文献
123.
Jean-Louis Aubagnac Franoise Debart Driss Mrani Gilles Gosselin Bernard Rayner Jean-Louis Imbach 《Journal of heterocyclic chemistry》1991,28(1):145-151
The fast-atom bombardment (FAB) mass spectra of a series of netropsin derivatives and analogues were examined in positive-ion and when necessary negative-ion modes. Behaviour of these derivatives was related to that of oligopeptides. Some compounds protected by t-butoxycarbonyl groups were also investigated using this technique and showed characteristic fragmentations. 相似文献
124.
Hammouda Chebbi Amen Allah Hajem Ahmed Driss 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(8):e333-e334
The crystal structure of the title compound, 2,2‐dimethyl‐1,3‐propanediammonium chromate, (C5H16N2)[CrO4], consists of layers built up from CrO42? tetrahedra alternating with diprotonated 2,2‐dimethylpropylendiamine molecules. N—H?O hydrogen bonds ensure the cohesion and stability of the structure. 相似文献
125.
Wassim Moslah Dorra Aissaoui-Zid Soioulata Aboudou Zaineb Abdelkafi-Koubaa Marie Potier-Cartereau Aude Lemettre Ines ELBini-Dhouib Naziha Marrakchi Didier Gigmes Christophe Vandier Jos Luis Kamel Mabrouk Najet Srairi-Abid 《Molecules (Basel, Switzerland)》2022,27(3)
Glioblastoma is the most aggressive and invasive form of central nervous system tumors due to the complexity of the intracellular mechanisms and molecular alterations involved in its progression. Unfortunately, current therapies are unable to stop its neoplastic development. In this context, we previously identified and characterized AaTs-1, a tetrapeptide (IWKS) from Androctonus autralis scorpion venom, which displayed an anti-proliferative effect against U87 cells with an IC50 value of 0.57 mM. This peptide affects the MAPK pathway, enhancing the expression of p53 and altering the cytosolic calcium concentration balance, likely via FPRL-1 receptor modulation. In this work, we designed and synthesized new dendrimers multi-branched molecules based on the sequence of AaTs-1 and showed that the di-branched (AaTs-1-2B), tetra-branched (AaTs-1-4B) and octo-branched (AaTs-1-8B) dendrimers displayed 10- to 25-fold higher effects on the proliferation of U87 cells than AaTs-1. We also found that the effects of the newly designed molecules are mediated by the enhancement of the ERK1/2 and AKT phosphorylated forms and by the increase in p53 expression. Unlike AaTs-1, AaTs-1-8B and especially AaTs-1-4B affected the migration of the U87 cells. Thus, the multi-branched peptide synthesis strategy allowed us to make molecules more active than the linear peptide against the proliferation of U87 glioblastoma cells. 相似文献
126.
A meshless method for numerical simulation of depth‐averaged turbulence flows using a k‐ϵ model
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A three‐dimensional numerical model is developed to analyze free surface flows and water impact problems. The flow of an incompressible viscous fluid is solved using the unsteady Navier–Stokes equations. Pseudo‐time derivatives are introduced into the equations to improve computational efficiency. The interface between the two phases is tracked using a volume‐of‐fluid interface tracking algorithm developed in a generalized curvilinear coordinate system. The accuracy of the volume‐of‐fluid method is first evaluated by the multiple numerical benchmark tests, including two‐dimensional and three‐dimensional deformation cases on curvilinear grids. The performance and capability of the numerical model for water impact problems are demonstrated by simulations of water entries of the free‐falling hemisphere and cone, based on comparisons of water impact loadings, velocities, and penetrations of the body with experimental data. For further validation, computations of the dam‐break flows are presented, based on an analysis of the wave front propagation, water level, and the dynamic pressure impact of the waves on the downstream walls, on a specific container, and on a tall structure. Extensive comparisons between the obtained solutions, the experimental data, and the results of other numerical simulations in the literature are presented and show a good agreement. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
127.
128.
Driss Ousaaid Hassan Laaroussi Hamza Mechchate Meryem Bakour Asmae El Ghouizi Ramzi A. Mothana Omar Noman Imane Es-safi Badiaa Lyoussi Ilham El Arabi 《Molecules (Basel, Switzerland)》2022,27(2)
The main objective of the current study was to determine the physicochemical properties, antioxidant activities, and α-glucosidase and α-amylase inhibition of apple vinegar produced by artisanal and industrial methods. Apple vinegar samples were analyzed to identify their electrical conductivity, pH, titratable acidity, total dry matter, Brix, density, mineral elements, polyphenols, flavonoids, and vitamin C. The antioxidant activity of apple vinegar samples was evaluated using two tests, total antioxidant capacity (TAC) and DPPH radical scavenging activity. Finally, we determined α-glucosidase and α-amylase inhibitory activities of artisanal and industrial apple vinegar. The results showed the following values: pH (3.69–3.19); electrical conductivity (2.81–2.79 mS/cm); titratable acidity (3.6–5.4); ash (4.61–2.90); °Brix (6.37–5.2); density (1.02476–1.02012), respectively, for artisanal apple vinegar and industrial apple vinegar. Concerning mineral elements, potassium was the most predominant element followed by sodium, magnesium, and calcium. Concerning bioactive compounds (polyphenols, flavonoids, and vitamin C), the apple vinegar produced by the artisanal method was the richest sample in terms of bioactive compounds and had the highest α-glucosidase and α-amylase inhibition. The findings of this study showed that the quality and biological activities of artisanal apple vinegar were more important than industrial apple vinegar. 相似文献
129.
Driss Ousaaid Hamza Mechchate Hassan Laaroussi Christophe Hano Meryem Bakour Asmae El Ghouizi Raffaele Conte Badiaa Lyoussi Ilham El Arabi 《Molecules (Basel, Switzerland)》2022,27(1)
The popularity of fruits vinegar (FsV) has been increased recently as a healthy drink wealthy in bioactive compounds that provide several beneficial properties. This review was designed in the frame of valorization of fruits vinegar as a by-product with high value added by providing overall information on its biochemical constituents and beneficial potencies. It contains a cocktail of bioactive ingredients including polyphenolic acids, organic acids, tetramethylperazine, and melanoidins. Acetic acid is the most abundant organic acid and chlorogenic acid is the major phenol in apple vinegar. The administration of fruits vinegar could prevent diabetes, hypercholesterolemia, oxidative stress, cancer, and boost immunity as well as provide a remarkable antioxidant ability. The production techniques influence the quality of vinegar, and consequently, its health benefits. 相似文献
130.