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131.
Tabti Hadja Alia Medjahed Baghdad Boudinar Mohamed Kadeche Abdelkader Bouchikhi Noria Ramdani Amina Taleb Safia Adjdir Mehdi 《Research on Chemical Intermediates》2022,48(6):2683-2703
Research on Chemical Intermediates - In this study, Mg-Fe(II)-Al-layered double hydroxide with different molar ratios Fe/Al (Mg0.80-Fe0.14-Al0.06-LDHs and Mg0.80-Fe0.20-Al0.00-LDHs) was prepared... 相似文献
132.
Ukrainian Mathematical Journal - We study Virasoro-type extensions of the q-deformed Witt Hom–Lie superalgebras. Moreover, we provide the cohomology of q-deformed Witt–Virasoro... 相似文献
133.
Dr. Malika Makhlouf Brahmi Dr. Cyril Portmann Danilo D'Ambrosio Dr. Tom M. Woods Damiano Banfi Patrick Reichenbach Laeticia Da Silva Emilie Baudat Dr. Gerardo Turcatti Prof. Dr. Joachim Lingner Prof. Dr. Karl Gademann 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(14):4596-4601
By using the Telospot assay, 27 different extracts of cyanobacteria were evaluated for telomerase inhibition. All extracts showed varying, but significant activity. We selected Microcystis aeruguinosa PCC 7806 to identify the active compound and a bioassay guided fractionation led us to isolate mixtures of sulfoquinovosyl diacylglycerols (SQDGs), which were identified by 2D NMR and MS/MS experiments. Pure SQDG derivatives were then synthesized. The IC50 values of pure synthetic sulfoquinovosyl dipalmitoylglycerol and the monopalmitoylated derivative against telomerase were determined to be 17 and 40 μM , respectively. A structure–activity relationship study allowed the identification of compounds with modified lipophilic acyl groups that display improved activity. 相似文献
134.
Abdelkader Djehiche Vladimir Canseco Aziz Omari Henri Bertin 《Comptes Rendus Mecanique》2009,337(9-10):682-692
This study deals with colloid transport in porous media which applications are found in subsurface water, petroleum engineering or civil engineering. An experimental study of colloidal polystyrene Latex particles deposition in a consolidated porous medium is presented. The influence of ionic strength of the colloid suspension and the flow rate on particle deposition is investigated. We see first that beyond a critical salt concentration, the total collector efficiency increases with the ionic strength. Moreover, such collector efficiency decreases as the flow rate increases according to theory. In other respects, using a γ ray attenuation technique allows us to measure local porosity fluctuation due to particles deposition. By this way deposition kinetics may be followed locally and precisely. Nevertheless when considering the thickness of the adsorbed layer over large scales, obtained results using the γ rays attenuation technique are found in good agreement with those obtained by means of an usual technique especially at latest stages of adsorption process. To cite this article: A. Djehiche et al., C. R. Mecanique 337 (2009). 相似文献
135.
Hachama Kamel Khadraoui Abdelkader Zouikri Mohamed Khodja Mohamed Khelifa Abdellah Echiker Khadidja Hammouti Belkheir 《Research on Chemical Intermediates》2016,42(2):987-996
Research on Chemical Intermediates - A new benzoxazin derivative, namely methyl 3-(2-oxo-2H-1,4-benzoxazin-3-yl) propanoate (1,4-MBXP), was synthesized under mild conditions from 2-aminophenols and... 相似文献
136.
The modified titanium electrode with lead film (PbTiE) was used for determination of trace levels of cadmium using square wave anodic stripping voltammetry (SWASV). The measurement of cadmium on the PbTiE has the best reply under the following conditions of PbTiE preparation: 10–3 mol L–1 Pb2+ in HCl (pH 1.0), deposition potential of–1.40 V vs. Ag/AgCl/KClsat and deposition time of 300 s. The PbTiE reveals highly linear behavior in the concentration range 5 × 10–8 to 10–6 mol L–1, with a limit of detection of 2 × 10–9 mol L–1. Interference of nine ionic species was evaluated. The measurements were carried out without removing dissolved oxygen from the solution. 相似文献
137.
Abdelkader Necer 《代数通讯》2013,41(12):6175-6189
Abstract Let 𝒢 be a simple finite dimensional Lie algebra over the complex numbers and let 𝒢¯ = 𝒢1 ⊕…⊕ 𝒢 k be a regular semisimple subalgebra of 𝒢 with each 𝒢 i being a simple algebra of type A or C. It is shown that the lattice of submodules of a generalized Verma 𝒢-module constructed by parabolic induction starting from a simple torsion free 𝒢¯-module is almost always isomorphic to the lattice of submodules of an associated module formed as a quotient of a classical Verma module by a sum of Verma submodules. In particular, it is shown that the Mathieu admissible Verma modules involved have maximal submodules which are the sum of Verma modules. 相似文献
138.
Using the averaging theory of first and second order we study the maximum number of limit cycles of generalized Linard differential systems{x = y + εh_l~1(x) + ε~2h_l~2(x),y=-x- ε(f_n~1(x)y~(2p+1) + g_m~1(x)) + ∈~2(f_n~2(x)y~(2p+1) + g_m~2(x)),which bifurcate from the periodic orbits of the linear center x = y,y=-x,where ε is a small parameter.The polynomials h_l~1 and h_l~2 have degree l;f_n~1and f_n~2 have degree n;and g_m~1,g_m~2 have degree m.p ∈ N and[·]denotes the integer part function. 相似文献
139.
In this article, a recent nonlinear alternative for contraction maps in Fréchet spaces due to Frigon and Granas [1998, Résultats de type Leray-Schauder pour des contractions sur des espaces de Fréchet, Ann. Sci. Math. Québec 22, 161–168] is used to investigate the existence and uniqueness of solutions for fractional order functional differential equations with infinite delay. 相似文献
140.
Meryem Bey Sabrina Badi Khairedine Fernane Amar Makhlouf 《Mathematical Methods in the Applied Sciences》2019,42(3):821-829
This paper concerns the bifurcation of limit cycles for a quartic system with an isochronous center. By using the averaging theory, it shows that under any small quintic homogeneous perturbations, at most 14 limit cycles birfucate from the period annulus of the considered system. 相似文献