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101.
Barachevsky V. A. Ait A. O. Gorelik A. M. Valova T. M. Zaichenko N. L. Kol’tsova L. S. Shienok A. I. Grachev V. P. Aldoshin S. M. 《Russian Journal of General Chemistry》2018,88(12):2773-2786
Russian Journal of General Chemistry - The results of the authors’ studies on development of a multilayer photochromic sun-protective energy-saving polymer film able of reversibly changing... 相似文献
102.
The Ugi-Smiles reaction of S-benzyl thiouracil have been exploited in several three-step sequences for the preparation of aminopyrimidine libraries with high diversity. After the 4-component coupling, oxidation of the thioether to sulfone is followed by displacement of the latter by various carbon-centered nucleophiles (cyanide, malonate, boronic acids) or amines. The efficiency of the whole sequence was further demonstrated with one-pot procedures. 相似文献
103.
Hanane Ait Hmeid Mustapha Akodad Mourad Baghour Abdelmajid Moumen Ali Skalli Ghizlane Azizi Hicham Gueddari Mostapha Maach Mimoun Aalaoul Ahmed Anjjar Lahcen Daoudi 《Molecules (Basel, Switzerland)》2021,26(18)
The main objective of this work was to contribute to the reduction in the contamination of phenolic compounds contained in margin by an adsorption process on two types of raw bentonite. The margin used in the studies was collected from a semi-modern oil mill located in the Nador–Morocco region. The results of the physico-chemical analyses showed that the effluents of the oil mills showed that they are highly polluted, particularly in terms of the total suspended solids (TSS), chemical oxygen demand (COD), and iron content of around 154.82 (mg/L), and copper content of 31.72 (mg/L). The mineralogy of bentonites studied by X-ray diffraction (XRD) reveals the existence of two types of montmorillonite; theoretically, the diffraction peak (001) of the montmorillonite appears at 15 Å, with a basal spacing that corresponds to a calcium pole, and the diffraction peak (001) appears at 12Å, with a basal spacing that corresponds to a sodium pole. The specific surface area of the bentonite used is characterized by a large specific surface area, varying between 127.62 m2·g−1 and 693.04 m2·g−1, which is due to the presence of hydrated interleaved cations. This surface is likely to increase in aqueous solution depending on the solid/liquid ratio that modulates the degree of hydration. With a high cation exchange capacity (CEC) (146.54 meq/100 g), samples of margin mixed with raw bentonites at different percentages vary between 5% and 100%. The potential of Moroccan bentonite for the phenol adsorption of 9.17 (g/L) from aqueous solutions was investigated. Adsorption tests have confirmed the effectiveness of these natural minerals in reducing phenolic compounds ranging from 8.72% to 76.23% contained in the margin and the efficiency of heavy metal retention through microelements on raw bentonites. The very encouraging results obtained in this work could aid in the application of adsorption for the treatment of margin. 相似文献
104.
An adaptive least‐squares finite element method is used to solve the compressible Euler equations in two dimensions. Since the method is naturally diffusive, no explicit artificial viscosity is added to the formulation. The inherent artificial viscosity, however, is usually large and hence does not allow sharp resolution of discontinuities unless extremely fine grids are used. To remedy this, while retaining the advantages of the least‐squares method, a moving‐node grid adaptation technique is used. The outstanding feature of the adaptive method is its sensitivity to directional features like shock waves, leading to the automatic construction of adapted grids where the element edge(s) are strongly aligned with such flow phenomena. Using well‐known transonic and supersonic test cases, it has been demonstrated that by coupling the least‐squares method with a robust adaptive method shocks can be captured with high resolution despite using relatively coarse grids. Copyright © 1999 John Wiley & Sons, Ltd. 相似文献
105.
Brahim Ait Addi Abdelaziz Ait Addi Abdul Shaban El-Habib Ait Addi Mohamed Hamdani 《Electroanalysis》2021,33(2):400-411
The inhibition efficiency of H2PO42− ions against tin corrosion in 0.2 M maleic acid is studied using electrochemical methods, surface analytical methods, and thermodynamic analysis. The potentiodynamic polarization plots showed the presence of an active/passive transition state of the tin electrode. The EIS measurements confirmed that the inhibition efficiency of H2PO42− increased by increasing the concentration (η=81 % at Cinh=2.10−2 M) and decreased by rising the temperature. The polarization tests demonstrated that the inhibitor performs as a cathodic-type. The adsorption of the inhibitor was spontaneous and followed the Langmuir adsorption isotherm. A model of the inhibition mechanism was suggested. 相似文献
106.
N. L. Zaichenko A. I. Shienok L. S. Kol’tsova A. V. Lyubimov I. R. Mardaleishvili V. M. Retivov S. K. Belus’ A. O. Ait 《Russian Journal of General Chemistry》2016,86(5):1022-1027
A novel hybrid compound composed of substituted imidazole and salicylideneaniline luminophors has been synthesized and shown to exhibit multiple luminescence in ethanol, which can be switched by varying the excitation wavelength. 相似文献
107.
Hossni Ziyat Moulay Youssef Ait Itto Mustapha Ait Ali Abdellah Karim Abdelkhalek Riahi Jean-Claude Daran 《Journal of chemical crystallography》2011,41(3):338-342
Abstract
The title compounds C11H16Cl2O3 (III) and C11H16Br2O3 (IV) have been prepared from (S)-Limonen. Their crystal structure and absolute configuration have been determined by X-ray analysis which confirmed the 1′S absolute configuration at the cyclopropyl moiety, in agreement with the known absolute configuration of the starting material. Both (III) and (IV) are orthorhombic, space group P212121 with a = 7.2558(4) ? (for III) 7.4058(6) ? (for IV), b = 9.7885(5) ? (for III) 9.7459(7) ? (for IV), c = 17.7551(10) ? (for III) 18.0354(14) ? (for IV), α = 90°, β = 90°, γ = 90° and Z = 4. 相似文献108.
Said SA Fernandez C Greff S Torre F Derridj A Gauquelin T Mevy JP 《Molecules (Basel, Switzerland)》2011,16(3):2646-2657
Three different altitudes were selected to study the variability of terpenoid composition from leaves of female plants of Pistacia lentiscus L. throughout the elevation gradient. GC-MS analyses showed that terpenoid contents change with altitude. Forty nine compounds were identified with a high interpopulation variability for low- and midaltitude sites that also exhibited the same major components when data were expressed on dry weight basis. However, Two-Way-ANOVA followed by Tukey's post hoc test showed that monoterpene hydrocarbons increased with elevation, giving values of 21.7, 37.5 and 221.5 μg g?1 dw for low- mid- and highlands, respectively. On the other hand, applying P.C.A. with data expressed in percentage of the chromatogram of the volatile extract led to the identification of three chemotypes associated with altitudinal levels. In highlands (Group I), the major compounds were β-caryophyllene (12%), δ-cadinene (9.3%) and a-pinene (6.3%) while in midlands (Group II), β-caryophyllene (11.5%), δ-cadinene (8.6%) and caryophyllene oxide (6.8%) were the main components. In lowlands (Group III) δ-cadinene (10.9%), cubebol (10.5%) and β-bisabolene (7.7%) were chiefly present. Hence, the involvement of genetic factors, temperature and drought in the chemical polymorphism of P. lentiscus associated with elevation is discussed in this report. 相似文献
109.
110.
Fahim Zakaria Mohyi Eddine Bouzzine Si Mohamed Ait Aicha Youssef Bouachrine Mohammed Hamidi Mohamed 《Research on Chemical Intermediates》2018,44(3):2009-2023
Research on Chemical Intermediates - The dye-sensitized solar cells containing a triphenylamine unit as the electron donor connected with a terminal cyanoacrylic acid electron acceptor by... 相似文献