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61.
Kanger T Kriis K Laars M Kailas T Müürisepp AM Pehk T Lopp M 《The Journal of organic chemistry》2007,72(14):5168-5173
Monosalts of N-substituted bimorpholine derivatives are efficient organocatalysts in intramolecular and intermolecular aldol reactions. The properties of the catalysts can be tuned either by the selection of an appropriate acid for the salt formation or by the change of a substituent at the nitrogen atom. In aldol condensation, i-Pr-substituted bimorpholine is the most stereoselective catalyst affording products in high yield with enantioselectivities up to 95% ee. 相似文献
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Long liquid slugs reaching a length of several hundreds of pipe diameter may appear when transporting gas and liquid in horizontal or nearly horizontal pipelines. These long slugs may cause system vibration, separator flooding, and operational problems for the downstream processing facilities. Although mainly short hydrodynamic slugs have been observed in offshore gas and oil production fields over the past years, the appearance of the long slugs is becoming more common as many production fields are now more mature and reach end of field life, giving reduced production rates and reduced operational pressure. 相似文献
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Safaei Mohammad Reza Tlili Iskander Gholamalizadeh Ehsan Abbas Tehseen Alkanhal Tawfeeq Abdullah Goodarzi Marjan Dahari Mahidzal 《Journal of Thermal Analysis and Calorimetry》2021,143(3):2453-2462
Journal of Thermal Analysis and Calorimetry - The main aim of the present research is to measure the nucleate boiling heat transfer coefficient (BHTC) of aqueous glycol nano-suspension as a coolant... 相似文献
66.
Complex perovskite oxides Ca2?xPrxMnO4 (x = 0–0.5) compounds were synthesized by a solid-state reaction technique. A tetra–ortho structural transition was observed. Impedance spectroscopy was used to study the electrical behavior in the frequency range 40 Hz–1 MHz and in the temperature range 80–350 K. Frequency-dependent conductivity spectra were found to obey the Jonscher's power law. Complex impedance plane plots have indicated that the dielectric response is mainly intrinsic. Materials bulk response was found to be dominated by non-localized or localized conduction, depending on temperature and frequency. 相似文献
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Kerehalli Vinayaka Prasad Hanumesh Vaidya Fateh Mebarek Oudina Khalid Mustafa Ramadan Muhammad Ijaz Khan Rajashekhar Choudhari Rathod Kirankumar Gulab Iskander Tlili Kamel Guedri Ahmed M. Galal 《印度化学会志》2022,99(8):100617
Due to the illuminating function of nanoliquids in several technological and medicinal domains, particularly in liquid transport processes known as peristalsis, inquisitive researchers have investigated the flow of peristaltic nanofluids. Consequently, the current study investigates the entropy production and magnetic influence on the peristaltic transport of heat and mass transport of Casson nanofluid in a non-uniform channel under convective circumstances. Utilizing the perturbation approach, fields of concentration, temperature, and velocity are derived from non-linear coupled partial differential equations (PDE). Entropy generation studies have been done. In addition, the influence of associated factors via specific physical terms, including the Sherwood number, the skin-friction coefficient, and the Nusselt number, for both Casson and Newtonian liquids, as well as the trapping phenomena, is visually examined. 相似文献
68.
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
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Copper‐Catalyzed Arylation of Nitrogen Heterocycles from Anilines under Ligand‐Free Conditions 下载免费PDF全文
Dounia Toummini Dr. Anis Tlili Julien Bergès Prof. Fouad Ouazzani Dr. Marc Taillefer 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(45):14619-14623
The arylation of pyrazole and derivatives can be achieved by coupling arenediazonium species (formed in situ from anilines) by using a catalytic system that employs low‐toxicity and inexpensive copper metal under very mild and ligand‐free conditions (T=20 °C). From other nitrogen heterocycles, the presence of an additive (NBu4I) significantly improves the efficiency of the catalytic system. These results represent the first examples of C?N bond formation from arenediazonium species. 相似文献