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21.
A modified HWE reaction using triethylamine and lithium bromide with ethyl bis(trifluoroethyl)phosphonoacetate gives satisfactory yields of α,β-unsaturated esters from a variety of ketones. 相似文献
22.
A reactive zinc powder is obtained by addition of ZnCl2 to a lithium dispersion suspended in ether. Reformatsky Reactions with the zinc powder are described. 相似文献
23.
Caterina Calgaro Meriem Ezzoug Ezzeddine Zahrouni 《Mathematical Methods in the Applied Sciences》2017,40(1):92-105
In this paper, we study a multiphasic incompressible fluid model, called the Kazhikhov–Smagulov model, with a particular viscous stress tensor, introduced by Bresch and co‐authors, and a specific diffusive interface term introduced for the first time by Korteweg in 1901. We prove that this model is globally well posed in a 3D bounded domain. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
24.
M. Ostafin Ph. Lavalle R. Ezzeddine P. -F. Ogier J. -F. Stoltz B. Senger 《Journal of colloid and interface science》1999,210(2):391
Computer simulations of the irreversible adhesion of charged colloidal particles at a solid/liquid interface are performed to determine whether the distribution of particles in the vicinity of a preadsorbed (also charged) one follows the Boltzmann law applied to ana prioriuniform adhesion probability, as first assumed by Adamczyket al.(J. Colloid Interface Sci.140, 123 (1990)). If true, this would indicate that the whole information on the deposition process is contained in the potential energy distribution on the adsorbing surface. In general, diffusion in a field of force and the irreversibility of the process induce significant deviations from the Boltzmann-weighted uniform adhesion density. Nevertheless, it is shown that for particles characterized by a small gravitational energy this procedure leads to a reasonable first approximation of the distribution of the particles over the adsorbing surface. This observation thus demonstrates the validity of Adamczyk's assumption and extends its range of applicability to the case of a weak gravitational field. 相似文献
25.
NMR spectra of proton, fluorine-19 and carbon-13 satellites of partially oriented propargyl fluoride have enabled the complete structure of this molecule to be determined. Agreement with microwave results is excellent, except for the carbon-fluorine bond length. Signs of all indirect coupling constants have been determined. 相似文献
26.
The proton NMR spectrum and carbon-13 satellites of partially oriented propyne give the complete structure of this molecule. Agreement with microwave results is excellent. 相似文献
27.
Khabbouchi Mohamed Hosni Khaled Srasra Ezzeddine 《Russian Journal of Applied Chemistry》2017,90(12):2046-2054
Russian Journal of Applied Chemistry - The various molar ratios of P/Si + Al (0.1, 0.2, 0.4, and 1.4), based on metakaolin and phosphoric acid, have been investigated at two temperatures 750 and... 相似文献
28.
Néji Besbes Houyem Jellali Patrick Pale Mohamed Lotfi Efrit Ezzeddine Srasra 《Phosphorus, sulfur, and silicon and the related elements》2013,188(4):883-889
Silica gel and activated clay, behaving as Lewis acids, reacted with N-acyl-2,2-dimethylaziridines 1 to lead to pentacoordinated aziridinium silicate ions. The regiospecific ring opening on the CMe2 carbon side of the intermediate I involves, after removal of the catalyst, the zwitterion II. The zwitterion II undergoes either a transfer of proton leading to the N-methallylamide 2 or intramolecular cyclization reaction leading to the oxazoline 3. The unstable oxazoline 3 on catalyst is hydrated in turn into amidoalcohol 4 via the oxazolinium silicate III. 相似文献
29.
Evaluation of phosphate removal from water by calcined-LDH synthesized from the dolomite 总被引:1,自引:0,他引:1
In the present study, the characteristics of the adsorption of phosphate on calcined layered double hydroxides (LDHs) from
aqueous solution were evaluated under laboratory conditions. The anionic clays were Mg3pH10-LDH synthesized by co-precipitation and D 1pH10-LDH synthesized from the dolomite. The equilibrium isotherm showed that the uptake of phosphate ion by Mg3pH10(500)-LDH was in agreement with the Langmuir and Freundlich equations; the Langmuir model gave a better fit to the experimental
data than the Freundlich one. The equilibrium isotherm showed, however, that the adsorption of the phosphate on D1pH10(500)-LDH was accompanied with precipitation reac tion of the phosphate salts. A mechanism proposed for the removal of phosphate
ion has been confirmed by X-ray diffraction and FT-IR spectroscopy. 相似文献
30.