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81.
Bridging β‐Cyclodextrin Prevents Self‐Inclusion,Promotes Supramolecular Polymerization,and Promotes Cooperative Interaction with Nucleic Acids 下载免费PDF全文
Dr. Pierre Evenou Dr. Julien Rossignol Dr. Gaëlle Pembouong Adélie Gothland Dr. Dmitri Colesnic Dr. Renaud Barbeyron Dr. Sergii Rudiuk Prof. Anne‐Geneviève Marcelin Dr. Mickaël Ménand Prof. Damien Baigl Prof. Vincent Calvez Dr. Laurent Bouteiller Prof. Matthieu Sollogoub 《Angewandte Chemie (International ed. in English)》2018,57(26):7753-7758
82.
This paper describes a slope scaling heuristic for solving the multicomodity capacitated fixed-charge network design problem. The heuristic integrates a Lagrangean perturbation scheme and intensification/diversification mechanisms based on a long-term memory. Although the impact of the Lagrangean perturbation mechanism on the performance of the method is minor, the intensification/diversification components of the algorithm are essential for the approach to achieve good performance. The computational results on a large set of randomly generated instances from the literature show that the proposed method is competitive with the best known heuristic approaches for the problem. Moreover, it generally provides better solutions on larger, more difficult, instances. 相似文献
83.
Christophe Loup Dr. Ana Tesouro Vallina Dr. Yannick Coppel Dr. Ulla Létinois Prof. Dr. Yasuo Nakabayashi Dr. Bernard Meunier Prof. Dr. Bernhard Lippert Dr. Geneviève Pratviel 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(37):11420-11431
Two PtIV and two PtII complexes containing a 2,2′‐bipyridine ligand were treated with a short DNA oligonucleotide under light irradiation at 37 °C or in the dark at 37 and 50 °C. Photolysis and thermolysis of the PtIV complexes led to spontaneous reduction of the PtIV to the corresponding PtII complexes and to binding of PtII 2,2′‐bipyridine complexes to N7 of guanine. When the reduction product was [Pt(bpy)Cl2], formation of bis‐oligonucleotide adducts was observed, whereas [Pt(bpy)(MeNH2)Cl]+ gave monoadducts, with chloride ligands substituted in both cases. Neither in the dark nor under light irradiation was the reductive elimination process of these PtIV complexes accompanied by oxidative DNA damage. This work raises the question of the stability of photoactivatable PtIV complexes toward moderate heating conditions. 相似文献
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86.
The two kinds of experiments actually existing in phase conjugation and production of images by backward stimulated scatterings are explained on the basis of the holographic model. The conditions for the correct transfer of information from one wavelength to another are presented. 相似文献
87.
Hureau C Blanchard S Nierlich M Blain G Rivière E Girerd JJ Anxolabéhère-Mallart E Blondin G 《Inorganic chemistry》2004,43(14):4415-4426
Two heptacoordinated Mn(II) complexes are isolated and X-ray characterized using the well-known tpen ligand (tpen = N,N,N',N'-tetrakis(2-pyridylmethyl)-1,2-ethanediamine): [(tpen)Mn(OH(2))](ClO(4))(2) (1(ClO(4))(2)) and [(tpen)Mn(micro-OAc)Mn(tpen)](ClO(4))(3).2H(2)O (2(ClO(4))(3).2H(2)O). Crystallographic data for 1(ClO(4))(2) at 110(2) K (respectively at 293(2) K): monoclinic, space group C2/c, a = 15.049(3) A (15.096(3) A), b = 9.932(2) A (10.105(2) A), c = 19.246(4) A (19.443(4) A), beta = 94.21(3) degrees (94.50(3) degrees ), Z = 4. Crystallographic data for 2(ClO(4))(3).0.5(C(2)H(5))(2)O at 123(2) K: triclinic, space group P, a = 12.707(3) A, b = 12.824(3) A, c = 19.052(4) A, alpha = 102.71(3) degrees, beta = 97.83(3) degrees, gamma = 98.15(3) degrees, Z = 2. Investigation of the variation upon temperature of the molar magnetic susceptibility of compound 2(ClO(4))(3).2H(2)O reveals a weak antiferromagnetic exchange interaction between the two high-spin Mn(II) ions (J = -0.65 +/- 0.05 cm(-)(1), H = -JS(1).S(2)). EPR spectra are recorded on powder samples and on frozen acetonitrile solutions, demonstrating the maintenance upon dissolution of the heptacoordination of Mn in complex 1 while complex 2 partially dissociates. Electrochemical responses of complexes 1 and 2 are investigated in acetonitrile, and bulk electrolyses are performed at oxidative potential in the presence of various amounts of 2,6-lutidine (0-2.65 equiv per Mn ion). The formation from either 1 or 2 of the mixed-valent complex [(tpen)Mn(III)(micro-O)(2)Mn(IV)(tpen)](3+) (3) is established from mass spectrometry and EPR and IR spectroscopy measurements. When reaction is started from 2, formation of [(tpen)Mn(IV)(micro-O)(2)(micro-OAc)Mn(IV)](3+) (4) is evidenced from cyclic voltammetry, EPR, and UV-vis data. The Mn vs tpen ratio in the electrogenerated complexes is accurately controlled by the quantity of additional 2,6-lutidine. The role of tpen as a base is discussed. 相似文献
88.
Loren G. Hepler Zorawar S. Kooner Geneviève Roux-Desgranges Jean-Pierre E. Grolier 《Journal of solution chemistry》1985,14(8):579-594
In the ideal associated solution model, activity coefficients of all species (labelled A, B, and AB here) are taken to be unity at all mole fractions and all temperatures, with several derivative consequences that have not previously been investigated. We have applied this model to an analysis of the thermodynamic properties (vapor pressures, excess volumes, excess enthalpies, partial molar enthalpies of solution, and excess heat capacities) of the chloroform + triethylamine system in terms of K, V, H, and C
p
for the equilibrium represented by A+B=AB. It is shown that there is good consistency between the relatively simple chemical ideal associated solution model and all available thermodynamic data except heat capacities, for which the consistency between model and data is less good. Some limitation of the ideal associated solution model are discussed, along with the relationship of this model to hydrogen bonding in the AB complex and to spectroscopic investigations. New thermal (partial molar enthalpies of solution and excess heat capacities) and volumetric data are presented. 相似文献
89.
90.
St-Pierre G Chagnes A Bouchard NA Harvey PD Brossard L Ménard H 《Langmuir : the ACS journal of surfaces and colloids》2004,20(15):6365-6373
Original and versatile new materials for the electrocatalytic hydrogenation of organic compounds were designed. The materials consist of reticulated glassy carbon cathode electrodes in which the modified silica particles (average diameter 40-63 microm) were dynamically circulated. The modification of the silica surface is 2-fold. First, the silica is surface-modified using organic functions such as -OSi(CH3)2(CH2)3OCH2CH-(OH)(CH)2OH (SiO2-Diol), -OSi(CH3)2(CH2)7CH3 (SiO2-C8), and -OSi(CH3)2C6H5 (SiO2-Phenyl). Second, these silica particles were further modified by vapor phase deposition of nickel nanoaggregates (used as sites for hydrogen atoms and electric contacts with the electrode material), which does not destroy or alter the organic functionalization as demonstrated by thermogravimetric analysis-mass spectrometry and Raman, diffuse reflectance IR Fourier transform, and Auger electron spectroscopies. The new concept stems from relative adsorption and desorption properties of the organic molecules and their corresponding reduced products into the organic functionalization of the surface-modified silica. In this work, the electrocatalytic hydrogenation cyclohexanone was used to test the concept. The performances (amount of cyclohexanol vs time of generated electrolysis at constant current) are measured and compared for the various bonded organic functions of the silica surface listed above, along with the unmodified silica particles (but still containing nickel nanoaggregates) and the presence or absence of methanol in solution. The measurements of the adsorption isotherms of cyclohexanone, and the calculations of the interaction energies (MM3 force field) between the chemisorbed organic functions and the substrates, corroborate perfectly the electrocatalysis results. 相似文献