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41.
Eduardo Marques de Sá 《Linear and Multilinear Algebra》2019,67(8):1711-1712
42.
Numerical Algorithms - In this paper, we propose and study the iteration complexity of an inexact Douglas-Rachford splitting (DRS) method and a Douglas-Rachford-Tseng’s forward-backward (F-B)... 相似文献
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M. Amélia Santos Adelino Afonso M. Matilde Marques Craig Wilcox 《Supramolecular chemistry》2013,25(3):201-215
Abstract New receptors based upon a carboxamidonaphthyridine unit derivatized with the polyaromatic segments [4-(1-pyrenyl)butyroylamino] and [3-(9-anthracenyl)propanoylamino] have been synthesized and studied by 1H NMR titration in their binding interaction to the guanosine-C8 adducts from the carcinogens 2-acetylaminofluorene and 2-aminofluorene. The high binding energy, in comparison with that of the non-derivatized analogues, is rationalized in terms of a bi-site interaction (hydrogen bonding and aromatic stacking). Although many factors may contribute to the strength of the host-guest complexes described herein, it appears that in some cases π-π interaction may induce a concomitant bending in the hydrogen bond system. 相似文献
47.
Anderson A. B. C. Júnior Gustavo S. G. De Carvalho Lippy F. Marques Charlane C. Corrêa Adilson D. Da Silva Flvia C. Machado 《Acta Crystallographica. Section C, Structural Chemistry》2013,69(8):934-936
The title compound, C14H11NO4, exists in the solid phase in the zwitterionic form, 2‐{[(4‐carboxy‐3‐hydroxyphenyl)iminiumyl]methyl}phenolate, with the H atom from the phenol group on the 2‐hydroxybenzylidene ring transferred to the imine N atom, resulting in a strong intramolecular N—H...O hydrogen bond between the iminium H atom and the phenolate O atom, forming a six‐membered hydrogen‐bonded ring. In addition, there is an intramolecular O—H...O hydrogen bond between the carboxylic acid group and the adjacent hydroxy group of the other ring, and an intermolecular C—H...O contact involving the phenol group and the C—H group adjacent to the imine bond, connecting the molecules into a two‐dimensional network in the (10) plane. π–π stacking interactions result in a three‐dimensional network. This study is important because it provides crystallographic evidence, supported by IR data, for the iminium zwitterionic form of Schiff bases.<!?tpb=12pt> 相似文献
48.
Paula Gomes Maria João Araújo Eduardo F. Marques Soraia Falcão Rodrigo O. Brito 《合成通讯》2013,43(12):2025-2036
Double-chained surfactants with potential biocompatibility have been prepared in high yields by lysine acylation with four natural saturated fatty acids (C6 to C12) and with cis-undec-5-enoic acid. The surfactants were found to assemble into nanotubules in aqueous medium and, when mixed with a commercial cationic surfactant, to spontaneously form liposomes. 相似文献
49.
Sheyla Santa Isabel Marques Iracema Andrade Nascimento Paulo Fernando de Almeida Fábio Alexandre Chinalia 《Applied biochemistry and biotechnology》2013,171(8):1933-1943
Microalgae farming has been identified as the most eco-sustainable solution for producing biodiesel. However, the operation of full-scale plants is still limited by costs and the utilization of industrial and/or domestic wastes can significantly improve economic profits. Several waste effluents are valuable sources of nutrients for the cultivation of microalgae. Ethanol production from sugarcane, for instance, generates significant amounts of organically rich effluent, the vinasse. After anaerobic digestion treatment, nutrient remaining in such an effluent can be used to grow microalgae. This research aimed to testing the potential of the anaerobic treated vinasse as an alternative source of nutrients for culturing microalgae with the goal of supplying the biodiesel industrial chain with algal biomass and oil. The anaerobic process treating vinasse reached a steady state at about 17 batch cycles of 24 h producing about 0.116 m3CH4 kgCODvinasse ?1. The highest productivity of Chlorella vulgaris biomass (70 mg l?1 day?1) was observed when using medium prepared with the anaerobic digester effluent. Lipid productivity varied from 0.5 to 17 mg l?1 day?1. Thus, the results show that it is possible to integrate the culturing of microalgae with the sugarcane industry by means of anaerobic digestion of the vinasse. There is also the advantageous possibility of using by-products of the anaerobic digestion such as methane and CO2 for sustaining the system with energy and carbon source, respectively. 相似文献
50.
Rodrigues Ana Luísa Marques Rosa Dias Maria Isabel Prudêncio Maria Isabel Russo Dulce Diniz Mariana Martins Andrea Neves César Kasztovszky Zsolt Harsányi Ildiko Szilágyi Veronika Kovács Imre Szőkefalvi-Nagy Zoltán 《Journal of Radioanalytical and Nuclear Chemistry》2022,331(9):3887-3903
Journal of Radioanalytical and Nuclear Chemistry - A contribution to the discussion about Vila Nova de São Pedro (VNSP) as a production centre of symbolic lithic artefacts, the origin of raw... 相似文献