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101.
P. Perez‐Tejeda A. Jimenez‐Ruiz E. M. Grueso R. Prado‐Gotor C. Carrasco A. Pastor N. Alvarez M. Garcia‐Lora M. Garcia‐Pageo 《国际化学动力学杂志》2013,45(12):780-786
The electron transfer reaction between [Ru(NH3)5pz]2+ and [Co(C2O4)3]3? was studied in the presence of monomers and aggregates of bile salts (sodium deoxycholate, sodium taurodeoxycholate, and sodium glycocholate) at 298.2 ± 0.1 K. The results show a decreasing rate constant with the successive addition of bile salts. To rationalize the trends of the reaction rate on the [bile salts], two models were used. One of them takes into account the aggregation feature by considering a stepwise self‐association between monomers, whereas the other assumes the formation of a critical micellar concentration. Binding constants between [Ru(NH3)5pz]2+ species and deoxycholate or taurodeoxycholate aggregates were higher than that for glycocholate aggregates. These results are consistent with the way in which the monomers are added to form the bile anion aggregates. 相似文献
102.
Baptiste Schindler Agathe Depraz Depland Gina Renois-Predelus Gabriel Karras Bruno Concina Gulabi Celep Jacques Maurelli Vincent Loriot Eric Constant Richard Bredy Christian Bordas Franck Lépine Isabelle Compagnon 《International Journal for Ion Mobility Spectrometry》2017,20(3-4):119-124
An original workflow allowing inline FAIMS separation, electrospray ionization, mass analysis and ion spectroscopy (IRMPD: InfraRed Multiple Photon Dissociation) is presented for multidimensional molecular analysis. This new instrument consists of an ultraFAIMS (Owlstone) device interfaced to a linear ion trap (LTQ XL Thermo Scientific) which was modified for IRMPD spectroscopy. Two modes of operation are demonstrated on an isomeric mixture of paracetamol and 2-phenylglycine. In the first mode a FAIMS (high-Field Asymmetric waveform Ion Mobility Spectrometry) separation of the isomers is performed with a static compensation field for mass- and isomer- selective ion spectroscopy. In the second mode, the compensation field is scanned while the ions are irradiated at a fixed wavenumber. The advantages of this workflow as compared to traditional FAIMS-MS and IRMPD spectroscopy are described. The potential of the two modes for molecular spectroscopy and analytical applications, in particular the new “omics” are discussed. 相似文献
103.
Prof. Santiago Alvarez 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(19):4350-4377
After briefly reviewing the applications of the coordination ability indices proposed earlier for anions and solvents toward transition metals and lanthanides, a new analysis of crystal structures is applied now to a much larger number of coordinating species: anions (including those that are present in ionic solvents), solvents, amino acids, gases, and a sample of neutral ligands. The coordinating ability towards s-block elements is now also considered. The effect of several factors on the coordinating ability will be discussed: (a) the charge of an anion, (b) the chelating nature of anions and solvents, (c) the degree of protonation of oxo-anions, carboxylates and amino carboxylates, and (d) the substitution of hydrogen atoms by methyl groups in NH3, ethylenediamine, benzene, ethylene, pyridine and aldehydes. Hit parades of solvents and anions most commonly used in the areas of transition metal, s-block and lanthanide chemistry are deduced from the statistics of their presence in crystal structures. 相似文献
104.
Access to New Endoperoxide Derivatives by Electrochemical Oxidation of Substituted 3‐Azabicyclo[4.1.0]hept‐4‐enes
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Dr. Frédérick Nuter Dr. Abdou Khadre Djily Dimé Dr. Cheng Chen Dr. Lotfi Bounaadja Dr. Elisabeth Mouray Dr. Isabelle Florent Dr. Yvan Six Dr. Olivier Buriez Dr. Angela Marinetti Dr. Arnaud Voituriez 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(14):5584-5593
A series of substituted 3‐azabicyclo[4.1.0]hept‐4‐ene derivatives were prepared and analysed by cyclic voltammetry. Preparative aerobic electrochemical oxidation reactions were then carried out. Three original endoperoxides were isolated, characterised and subjected to antimalarial and cytotoxicity activity assays. 相似文献
105.
Camille Piovesan Anne-Laurence Dupont Isabelle Fabre-Francke Odile Fichet Bertrand Lavédrine Hervé Chéradame 《Cellulose (London, England)》2014,21(1):705-715
Two di-alkoxysilanes, with (AMDES, aminopropylmethyldiethoxysilane) or without (DMDES, dimethyldiethoxysilane) an amine function, and a tri-alkoxy aminosilane (APTES, aminopropyltriethoxysilane) as well as their mixtures were introduced in paper as fiber strengthening agents. The polymerization and copolymerization of these polysiloxanes in the paper were investigated. In all the cases where APTES was present, the formation of networks was established by measuring the soluble fraction amount extracted from the treated papers. A slight decrease of the opacity of the paper sheets when AMDES was part of the treatment was noted. The presence of APTES reduced this opacity loss. The study of the physicochemical properties of the treated paper (mechanical strength and alkalinity) demonstrated that, besides the required deacidification feature, the different treatments allowed an efficient strengthening of the cellulose fibers to various extents. Contact angle measurements indicated a decrease of the hydrophilic character of papers treated with the mixture APTES/AMDES and the occurrence of a hydrophobic character of the papers treated with APTES alone. These results were consistently obtained for both spray and immersion treatment processes. 相似文献
106.
107.
Mihaela Gulea Isabelle Abrunhosa Jozef Drabowicz Guillaume Grach Matthieu Hamel Serge Masson 《Phosphorus, sulfur, and silicon and the related elements》2013,188(5-6):1267-1272
Abstract A new method to prepare enantioenriched sulfinates was developed to obtain optically active ortho-methylsulfinyl(phenylphosphonates). It consists of a diastereoselective oxidation of sulfenates to sulfinates. Additionally, preliminary results concerning the synthesis of ortho-phophonylated benzylic thiol derivatives via a new P═S to P═C [1,4]-rearrangement and a first synthetic application of these compounds are also described. 相似文献
108.
The reaction of chloroacetyl chloride and triethylamine with a chiral imine derived from the combination of methyl glyoxylate and protected L-threonine gave two optically active α-amino acid derivatives with a cis-substituted β-lactam skeleton in a 72:28 ratio. The major product is obtained in 59% yield by simple crystallisation. 相似文献
109.
Emily F. Evans Norman J. Lewis Isabelle Kapfer Gregor Macdonald Richard J. K. Taylor 《合成通讯》2013,43(11):1819-1825
A mild and efficient procedure is described for the removal of the tert-butoxycarbonyl (BOC) group using boron trifluoride etherate and molecular sieves in dichloromethane at room temperature. The scope of this procedure is explored for the deprotection of a variety of amines including amino acid derivatives. 相似文献
110.
In network problems, latency is associated with the metric used to evaluate the length of the path from a root vertex to each vertex in the network. In this work we are dealing with two applications or variations of the minimum latency problem known as the repairman problem and the deliveryman problem. We have developed two integer formulations for the minimum latency problem and compared them with other two formulations from the literature for the time-dependent traveling salesman problem. The present work highlights the similarities and differences between the different formulations. In addition, we discuss the convenience of including a set of constraints in order to reduce the computation time needed to reach the optimal solution. We have carried out extensive computational experimentation on asymmetrical instances, since they provide the characteristics of the deliveryman and repairman problems in a better way. 相似文献