Performance comparison with different methods for ethanol/O2 biofuel cell based on NAD+ cofactor immobilized and activated by two types of carbon nanoparticles

Journal of Solid State Electrochemistry - Biofuel cells are an attractive alternative to conventional fuel cells, because they use biological catalysts. We report in this article the construction...     

Polyphenols contents,heavy metals analysis and in vitro antibacterial activity of extracts from Cladanthus arabicus and Bubonium imbricatum of Moroccan Origin

Abstract

Aim of this study was to evaluate polyphenols and major and trace elements of Cladanthus arabicus and Bubonium imbricatum, along with their in vitro antibacterial activity against six multidrug resistant Enterobacteriaceae (Escherichia coli S33/16, E. coli S34/16, Proteus mirabilis S32/16, Klebsiella pneumoniae S12/16, Enterobacter cloacae S5/16, and Salmonella sp S12/14). UV spectrophotometry, ultra-high-performance liquid chromatography coupled to mass spectrometry and inductively coupled plasma mass spectrometry were used to evaluate total polyphenol content, quali-quantitative profile of single polyphenols and inorganic elements of the extract. The antibacterial activity was investigated by standard methods. Twelve polyphenols were identified in both plants and these were more concentrated in B. imbricatum than C. arabicus extracts. High levels of minerals, essential trace elements and tolerable levels of heavy metals (Cd, As and Pb) were found. Furthermore, the extracts showed also a strong in vitro antibacterial activity, particularly versus E. coli S33/16 (MIC, 0.125?mg ml^?1).     

Competitive adsorption of anionic dyes onto DMOA modified MCM-41

Research on Chemical Intermediates - The single and binary adsorption of two anionic dyes Acid Yellow 17 (AY17) and Naphtol Green B (NGB) onto N–N–Dimethyl-n-octylamine (DMOA) modified...     

Hypersurfaces compactes d'un fibré vectoriel riemannien à courbure moyenne prescriteCompact hypersurfaces of a Riemannian vector bundle with prescribed mean curvature

Let M be a compact Riemannian manifold, E a Riemannian vector bundle on M and Σ the sphere subbundle of E. We look for embeddings of Σ into E admitting prescribed mean curvatures of various types. To cite this article: P. Cherrier, A. Hanani, C. R. Acad. Sci. Paris, Ser. I 335 (2002) 525–528.     

Global solutions and self-similar solutions of semilinear wave equation

We prove existence, uniqueness and regularity results for the global solutions of the semilinear wave equations. In particular, we show existence of regular self-similar solutions. Also, we build some finite-energy asymptotically self-similar solutions. Received: 20 September 1999; in final form: 10 May 2000 / Published online: 25 June 2001     

Faà di Bruno’s Formula and Modular Forms

We show that Faà di Bruno’s formula can play important roles in modular forms theory and in the study of differential operators of the form \( \displaystyle \left( a(x)\frac{d}{dx} \right) ^n\). We also emphasize the importance of the fundamental forms \(\displaystyle y_k= \Delta ^{-\frac{k}{12}}, \Delta \) is the discriminant function, making a link between some aspects of differential Galois theory and modular forms.     

Thermodynamic properties of the species resulting from the phenyl radical with O2 reaction system

Phenyl radicals are formed in combustion and oxidation systems by abstraction of the phenyl—hydrogen from benzene or aromatics by active radical species and by oxidation and thermal reactions of the benzylic carbon on alkyl‐substituted aromatics. The reaction of phenyl with O₂ leads to chain‐branching reactions and a number of unsaturated oxygenated hydrocarbon intermediates that may need to be included in detailed combustion models. Thermochemical parameters and structures on important species resulting from the phenyl radical + O₂ association and reaction are reported in this study. Enthalpies, Δ_f H, of a series of stable molecules, radicals, and transition state structures are calculated using ab initio (G3MP2B3 and G3) and density functional (DFT, B3LYP/6–311g(d,p) calculations, group additivity (GA), and literature data. The ab initio and density functional calculations are combined with isodesmic reaction analysis, whenever possible, to improve the accuracy of the enthalpy values. Entropies, S, and heat capacities, Cp_f298 (T), are calculated using density functional calculations, group additivity, and literature data. © 2008 Wiley Periodicals, Inc. Int J Chem Kinet 40: 583–604, 2008     

Reversible photomagnetic properties of the molecular compound [{Cu(bipy)2}2{Mo(CN)8}]·9H2O·CH3OH

The optical and photomagnetic properties of [{Cu^II(bipy)₂}₂{Mo^IV(CN)₈}]·9H₂O·CH₃OH (1) have been reinvestigated. A comparison between spectra in solution and in the solid state revealed the presence of an intervalence band (or Metal–Metal Charge Transfer, hereafter noted MMCT) at 570 nm. The photomagnetic properties have been performed in a Superconducting QUantum Interference Device at 10 K with irradiation in the range of the MMCT: 488 nm, 520 nm and 647 nm at 10 K. An important increase of the magnetic signal has been measured after 1 h of irradiation at 488 nm, whereas a weaker increase has been obtained for the irradiation at 520 nm in the same conditions. Moreover, after an excitation at 488 nm, an irradiation at 647 nm has induced a decrease of the magnetic moment, which corresponds to a partial deexcitation. The complete characterization of the photoproduct has been realised after an irradiation of 4 h at 488 nm. The photomagnetic properties have shown an increase of the paramagnetism of 1 at low temperature. After a thermal heating at 300 K, the material goes back to its initial state before irradiation. It is the first time that a fully reversible photomagnetic behaviour for the compound [{Cu^II(bipy)₂}₂{Mo^IV(CN)₈}]·9H₂O·CH₃OH has been described. The observed properties have been discussed in terms of an electron transfer mechanism Mo → Cu.     

A regiodivergent synthesis of ring a C-prenylflavones

Capitalizing on the use of orthogonal protecting groups and the development of a modified Robinson flavone synthesis that avoids harsh acidic conditions, a regioselective synthesis of 6- and 8-prenylflavones from the same prenylated disilylated phloracetophenone (9) has been developed, targeting cannflavin B (1d), the COX-inhibiting principle of marijuana, and its unnatural isomer isocannflavin B (1e) as model compounds.