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161.
Youssef Belmabkhout Gerhard Pirngruber Elsa Jolimaitre Alain Methivier 《Adsorption》2007,13(3-4):341-349
In this work a combination of static gravimetric and inverse chromatographic techniques is used to study the adsorption and
separation of the main synthesis gas components, i.e. CO2, CO, CH4 and H2. The single component adsorption isotherms of CO2, CO, CH4 and H2 on faujasite NaX were measured from 303 K to 473 K and over a large range of pressures (from 0 to 1200 kPa). Breakthrough
curves of CO2 and CO and their mixtures were determined at 323 K and 373 K and 100 kPa as an illustrative example. A nice agreement was
noticed between the two above-mentioned techniques for single component adsorption. Binary mixture dynamics measurements were
compared to the predictions of ideal adsorption solution theory (IAST) via the previously cited single component adsorption
data. 相似文献
162.
Mohamed Ghazzali Vratislav Langer Lars
hrstrm Morsy Abu‐Youssef 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(5):o312-o314
In the crystal structures of the title compounds, C12H12N42+·2BF4−, (I), and C12H11N4+·ClO4−, (II), respectively, infinite two‐ and one‐dimensional architectures are built up via N—H...F [in (I)] and conventional N—H...N [in (II)] hydrogen bonding. The N—N single bond in (I) lies on a crystallographic centre of symmetry; as a result, the two pyridinium rings are parallel. In (II), the pyridinium and pyridyl ring planes are inclined with a dihedral angle of 14.45 (3)°. 相似文献
163.
164.
Simona Sawan Khalil Hamze Ali Youssef Kamal Bouhadir Abdelhamid Errachid Rita Maalouf Nicole Jaffrezic-Renault 《Electroanalysis》2021,33(7):1789-1799
In this work the interaction characteristics of nucleobases with As(III) are studied. Novel materials consisting of magnetic nanoparticles (MNPs) functionalized with adenine hydrazide (AH), guanine hydrazide (GH) and uracil hydrazide (UH) were elaborated. The adsorption isotherms were investigated electrochemically and it was shown that the adsorption capacity of the nanoparticles towards arsenic (III) increased in the following order: AH<UH<GH. The electrochemical detection of As(III) using the GH functionalized MNPs offered better results compared with the other functionalizations, with a sensitivity of 1.92 μA μg−1 L and a limit of detection of 1.6 μg/L (21 nM). 相似文献
165.
In this paper, we prove some fixed point results for multivalued mappings in bounded metric spaces via symmetric spaces. Moreover an application to an integral inclusion is given.
相似文献166.
Youssef Hamadi Sa?d Jabbour Lakhdar Sa?s 《4OR: A Quarterly Journal of Operations Research》2012,10(1):15-32
Learning is a general concept, playing an important role in many Artificial intelligence domains. In this paper, we address
the learning paradigm used to explain failures or conflicts encountered during search. This explanation, derived by conflict
analysis, and generally expressed as a new constraint, is usually used to dynamically avoid future occurrences of similar
situations. Before focusing on clause learning in Boolean satisfiability (SAT), we first overview some important works on
this powerful reasoning tool in other domains such as constraint satisfaction and truth maintenance systems. Then, we present
a comprehensive survey of the most important works having led to what is called today—conflict driven clause learning (CDCL)—which
is one of the key components of modern SAT solvers. In theory, current SAT solvers with clause learning are as powerful as
general resolution proof systems. In practice, real-world SAT instances with millions of variables and clauses are now in
the scope of this solving paradigm. 相似文献
167.
Abdel-Hafez Gehan A. Aboraia Ahmed S. Mohammad Abdel-Mabood I. Youssef Adel F. 《平面色谱法杂志一现代薄层色谱法》2022,35(4):349-362
JPC – Journal of Planar Chromatography – Modern TLC - High-performance thin-layer chromatographic (HPTLC) method provides a simple, sensitive, and accurate analytical method for the... 相似文献
168.
Aequationes mathematicae - Our main result is that we describe the solutions $$g,f:S\rightarrow \mathbb {C}$$ of the functional equation $$\begin{aligned} g(x\sigma (y))=g(x)g(y)-f(x)f(y)+\alpha... 相似文献
169.
Uncertainty Principles for the Generalized Fourier Transform Associated with Spherical Mean Operator
The aim of this paper is to establish an extension of qualitative and quantitative uncertainty principles for the Fourier transform connected with the spherical mean operator. 相似文献
170.
Dr. Rosana Álvarez Claudio Martínez Youssef Madich J. Gabriel Denis Dr. José M. Aurrecoechea Prof. Dr. Ángel R. de Lera 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(42):12746-12753
Structurally diverse C3‐alkenylbenzofurans, C3‐alkenylindoles, and C4‐alkenylisoquinolones are efficiently prepared by using consecutive Sonogashira and cascade Pd‐catalyzed heterocyclization/oxidative Heck couplings from readily available ortho‐iodosubstituted phenol, aniline, and benzamide substrates, alkynes, and functionalized olefins. The cyclization of O‐ and N‐heteronucleophiles follows regioselective 5‐endo‐dig‐ or 6‐endo‐dig‐cyclization modes, whereas the subsequent Heck‐type coupling with both mono‐ and disubstituted olefins takes place stereoselectively with exclusive formation of the E isomers in most cases. 相似文献