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51.
Imen Soussi Ahlem Maalaoui Olivier Pérez Mohamed Rzaigui Samah Akriche 《Journal of Cluster Science》2016,27(6):1863-1876
A mixed-metal Lindqvist-type heteropolyanion of organic cation; (C8H14N2)2[V2W4O19]?2H2O (m-XDAV2W4) has been synthesized hydrothermally and characterized by means ICP and elemental analysis, X-ray diffraction, IR, UV–Vis, luminescence and biological analyses. The X-ray structural analysis supported by a detailed Hirshfeld surface analysis and fingerprint plots has been elucidated the different inter-contacts in the crystal structure mainly associated with O…H/H…O close contacts between [V2W4O19]4? (V2W4) clusters, water molecules and m-xylylenediammonium entities so stabilizing the 3D-supramolecular structure. The optical survey reveals an important HOMO–LUMO band gap indicating stability and blue luminescent behavior of reported material. Moreover, the biological trials indicated that this compound displays promising antibacterial and antifungal activities. 相似文献
52.
Faycal Abidi Mekki Ayadi Khaled Omrani 《Journal of Applied Mathematics and Computing》2008,27(1-2):293-305
A finite difference scheme is derived for the initial-boundary problem for the nonlinear equation system $$\frac{\partial u}{\partial t}=A\frac{\partial^{2}u}{\partial x^{2}}+f(u),$$ where A is a complex diagonal matrix, f is a complex vector function. The stability and convergence in discrete L ∞-norm of proposed Crank-Nicolson type finite difference schemes is proved. No restrictions on the ratio of time and space grid steps are assumed. Some numerical experiments have been conducted in order to validate the theoretical results. 相似文献
53.
Amira Zaouak Ahlem Noomen Haikel Jelassi 《Journal of Radioanalytical and Nuclear Chemistry》2018,316(1):37-47
Cesium uptake by natural zeolite clinoptilolite from Bulgaria was studied using batch technique and model solutions. The optimal conditions of interaction were determined. The pseudo-second-order rate model better describes the kinetic data obtained at different concentrations. The intraparticle diffusion and the surface diffusion models were tested to identify the rate-controlling step. The sites in the structure of clinoptilolite that are preferable for exchange were studied by application of Rietveld structural approach and the sequence of site occupation by cesium was followed. The Langmuir isotherm model provides a good fit of the equilibrium experimental data. The thermodynamic parameters for the system were calculated. 相似文献
54.
Inside Back Cover: Piling Up Pillar[5]arenes To Self‐Assemble Nanotubes (Chem. Eur. J. 18/2016)
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Belkadi Ahlem Kenouche Samir Melkemi Nadjib Daoud Ismail Djebaili Rachida 《Structural chemistry》2021,32(6):2235-2249
Structural Chemistry - In this paper, a combined approach based on a k-means algorithm and statistical analysis has been applied successfully to classify 500 cytotoxic agents using 21 molecular... 相似文献
58.
Surfaces of materials can be modified to ensure specific interaction features with microorganisms. The current work discloses biocidal properties of polystyrene (PS) Petri-dish surfaces that have been exposed to a dry gaseous-ozone flow. Such treated PS surfaces are able to inactivate various species of vegetative and sporulated bacteria on a relatively short contact time. Denaturation of proteins seems likely based on a significant loss of enzymatic activity of the lysozyme protein. Characterization of these surfaces by atomic-force microscopy (AFM), Fourier-transform infra-red (FTIR) spectroscopy and X-ray photoelectron spectroscopy (XPS) reveals specific structural and chemical modifications as compared to untreated PS. Persistence of the biocidal properties of these treated surfaces is observed. This ozone-induced process is technically simple to achieve and does not require active precursors as in grafting. 相似文献
59.
Thermal decomposition of cellulose has been widely studied for the past several years. It has been reported that the source of cellulose and its composition greatly affect its pyrolysis. One of the most widely used analytical tools for the study of cellulose pyrolysis is thermogravimetric (TG) analysis. Several model-fitting methods have been employed to study cellulose pyrolysis kinetics. An alternative to the model-fitting approach is the so-called model-free method developed by Vyazovkin. This isoconversional technique calculates the activation energy as a function of the degree of the conversion. In this article, the pyrolysis of cellulose in cotton fibers compared to microcrystalline cellulose (Avicel, PH 105) was investigated. TG curves were acquired as a function of the heating rates (4, 5, 8, 10, and 16 °C min?1) and the model-free method was used to analyze the data. Activation energies of cotton fibers and Avicel were obtained, and compared to the data reported in the literature. In addition, models for isothermal decomposition were calculated and compared with experimental data at the same temperature. 相似文献
60.
Tlili Kadri Noomen Khiari Faycal Abidi Khaled Omrani 《Numerical Methods for Partial Differential Equations》2008,24(6):1501-1516
L∞‐error estimates for finite element for Galerkin solutions for the Benjamin‐Bona‐Mahony‐Burgers (BBMB) equation are considered. A priori bound and the semidiscrete Galerkin scheme are studied using appropriate projections. For fully discrete Galerkin schemes, we consider the backward Euler method and analyze the corresponding error estimates. For a second order accuracy in time, we propose a three‐level backward method. © 2008 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2008 相似文献