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1.
P. De Montgolfier G.-A. Martin J.-A. Dalmon 《Journal of Physics and Chemistry of Solids》1973,34(5):801-812
The active phase of catalysts is often ferromagnetic. In such a case, one needs some knowledge on the mass and particles size distribution of the ferromagnetic phase, and on an eventual paramagnetic one. This can be achieved by pseudo inversion of a set of magnetization-magnetic fields data. The distribution function is represented by its moments or by a functional and an optimisation procedure is used. Fidelity and sensibility of the computation are tested using known distribution functions. The physical validity of the results is checked on nickel-on-silica catalysts by different ways: comparison between the computed and chemically titrated masses-invariance of the results with the temperature of experiments-comparison of distribution functions obtained by different physical methods. Results are given for Ni-SiO2 catalysts prepared by reduction at various temperatures. 相似文献
2.
Dr. Emmanuelle Rémond Dr. Jean-Alain Fehrentz Laure Liénart Prof. Sébastien Clément Dr. Jean-Louis Banères Dr. Florine Cavelier 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(47):e202201526
Synthesis of fluorescent P-hydroxybinaphtylphosphole-oxide or -sulfide was achieved by trapping a binaphtyl dianion with methyl dichlorophosphite or P-(N,N-diethylamino)dichlorophosphine, followed by oxidation or sulfuration of the P-center. After saponification or acid hydrolysis, the P-hydroxyphospholes were coupled to peptides using the coupling agent BOP, under the conditions required for the synthesis in solution or on a solid support. This new method was illustrated by the labeling of the JMV2959, a potent antagonist of the Growth Hormone Secretagogue Receptor type 1a (GHS−R1a). The labeled conjugates were used to characterize GHSR ligands by competition assays, based on Fluorescence Resonance Energy Transfer (FRET). Such P-hydroxyphosphole-oxide or -sulfide constitute a promising new class of compact fluorophores with large Stokes shift, for labeling biomolecules by grafting through the phosphorus atom. 相似文献
3.
Sonia CantelDamien Boeglin Marc RollandJean Martinez Jean-Alain Fehrentz 《Tetrahedron letters》2003,44(25):4797-4799
Anchoring of an α-amino-acid amide residue by its amine function to a carbamate resin followed by primary amide Hofmann rearrangement led to a gem-diamino residue linked to the resin. The generated primary amine could be acylated with various carboxylic compounds offering a large variety of molecules. Furthermore, this new solid-phase strategy allowed a reliable synthesis of a gem-diamino monomeric residue which could not be easily obtained in solution due to the limited stability of monocarbamate-protected gem-diaminoalkyl derivatives. 相似文献
4.
J. Dalmon 《Fresenius' Journal of Analytical Chemistry》1871,10(1):132
Ohne Zusammenfassung 相似文献
5.
We report on the synthesis of 1,2,4-triazoles substituted with 2 or 3 amino acid side chains, using silver benzoate as a key reagent for the cyclization step. A complete study of the optical purity retention during the synthetic process leading to these compounds is described. In addition an improved work-up after the addition-cyclization step was also established leading to better yields and metal-free products. 相似文献
6.
Marc Pera‐Titus Dr. Rayan El‐Chahal Volainiana Rakotovao Dr. Cécile Daniel Sylvain Miachon Dr. Jean‐Alain Dalmon Dr. 《Chemphyschem》2009,10(12):2082-2089
The properties of condensed matter are strongly affected by confinement and size effects at the nanoscale. Herein, we measured by microvolumetry the increased solubility of H2 in a series of solvents (CHCl3, CCl4, n‐hexane, ethanol, and water) when confined in the cavities of mesoporous solids (γ‐alumina, silica, and MCM‐41). Gas/liquid solubilities are enhanced by up to 15 times over the corresponding bulk values for nanoliquid sizes smaller than 15 nm as long as gas/liquid interfaces are mesoconfined in a porous network. Although Henry’s law constant apparently no longer applies under these confinement, the concentration of dissolved H2 still increases linearly with increasing pressure in the range 1–5 bar. We discuss the role and main implications of surface excess concentrations at mesoconfined gas/liquid interfaces in enhancing gas solubility. 相似文献
7.
Preparation of Some Thiazolyl Hydrazone Derivatives and Evaluation of Their Antibacterial Activities
Gülhan Turan-Zitouni Ahmet Özdemir Zafer Asım Kaplancıklı Jean-Alain Fehrentz Jean Martinez Pierre Chevallet 《Phosphorus, sulfur, and silicon and the related elements》2013,188(10):2613-2623
The increasing clinical importance of drug-resistant fungal and bacterial pathogens has provided additional urgency to microbiological research and to the development of new antibacterial compounds. For this purpose, new tert-butyl [1-aryl/alkyl-2[(4-aryl-2-thiazolyl)hydrazono]ethyl]carbamate derivatives were synthesized and evaluated for antibacterial activity. The reaction of Boc-L-phenylalaninal, Boc-D-phenylalaninal, Boc-L-leucinal, and Boc-L-tryptophanal with thiosemicarbazide yielded the thiosemicarbazones, which furnished the title compounds on reaction with phenacyl bromides. The new compounds were screened for antibacterial activity. The results from the bioassay tests show that some of the compounds have notable activity against Gram-positive bacteria. 相似文献
8.
CO adsorption at room temperature on Ni-Cu alloys supported on SiO2 is studied by two complementary techniques, infra-red spectroscopy and magnetic methods (saturation magnetization). The bond number between CO and the metallic surface calculated from magnetic data decreases from 1.8 to 1 as the Cu content increases. Two bands attributed to CO bonded to Ni are observed (the A band in the 2000–2050 cm?1 region, and the B band in the 1950–1900 cm?1 region). A small band assigned to CO bonded to Cu is also detected. As Cu content increases, the intensity of the B band decreases, and a noticeable and continuous frequency shift of the three bands is observed. Experimental results are fully accounted for assuming that: (i) two adsorbed species of CO on Ni, a monodentate and a bridged species (with small amounts of other multicentered species) are formed, as suggested by Eischens and Pliskin; (ii) dilution of Ni by Cu decreases the relative abundance of the bridged (and multicentered) species for some geometric reasons previously invoked by Soma-Noto and Sachtler; (iii) surface complexes are formed between CO and Ni; however Ni remains in its metallic state. The surface complex is sensitive to the electronic environment of the metallic atom, with a frequency shift of the three infra-red bands upon alloying as a consequence. 相似文献
9.
Jean-Alain Bousquet Jean Faure Jean-Pierre Fouassier Jean-Baptiste Donnet Bassel Haidar Alain Vidal 《Journal of polymer science. Part A, Polymer chemistry》1979,17(6):1685-1700
Photocrosslinking experiments were performed on elastomeric polymer films (EPDM) that contained benzoin derivatives as photosensitive initiators. Infrared (IR) and ultraviolet (UV) spectroscopy investigations were used in conjunction with physical property measurements. The results all together make it possible to discuss the crosslinking mechanism and pose interesting questions about the reactivity of benzoin derivatives in their excited states in relation to their efficiency in the crosslinking process. 相似文献
10.