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361.
Hernández PI Moreno D Javier AA Torroba T Pérez-Tomás R Quesada R 《Chemical communications (Cambridge, England)》2012,48(10):1556-1558
The tambjamine alkaloids and related synthetic analogs are potent transmembrane anion tranporters promoting bicarbonate/chloride exchange in model phospholipid liposomes and discharging pH gradients in living cells. 相似文献
362.
A Iglesias X Feás S Rodrigues JA Seijas MP Vázquez-Tato LG Dias LM Estevinho 《Molecules (Basel, Switzerland)》2012,17(7):8561-8577
In this study the characterization of a total of 60 honey samples with Protected Denomination of Origin (PDO) collected over three harvests (2009-2011, inclusive), from the Northeast of Portugal was carried out based on the presence of pollen, physicochemical and microbiological characteristics. All samples were found to meet the European Legislation, but some didn't meet the requirements of the PDO specifications. Concerning the floral origin of honey, our results showed the prevalence of rosemary (Lavandula pedunculata) pollen. The microbiological quality of all the analyzed samples was satisfactory, since fecal coliforms, sulfite-reducing clostridia and Salmonella were absent, and molds and yeasts were detected in low counts. Significant differences between the results were studied using one-way analysis of variance (ANOVA), followed by Tukey's HSD test. The samples were submitted to discriminant function analysis, in order to determine which variables differentiate between two or more naturally occurring groups (Forward Stepwise Analysis). The variables selected were in this order: diastase activity, pH, reducing sugars, free acidity and HMF. The pollen spectrum has perfect discriminatory power. This is the first study in which a honey with PDO was tested, in order to assess its compliance with the PDO book of specifications. 相似文献
363.
Modesto T. López-López Ana Gómez-Ramírez Guillermo R. Iglesias Juan D. G. Durán Fernando González-Caballero 《Adsorption》2010,16(4-5):215-221
We describe in this paper different and complementary experimental methods for assessing the adsorption of surfactants on metal particles in oil-based suspensions. Two different kinds of particles are dispersed in mineral oil: iron microparticles and CoNi nanoparticles. The adsorption of oleic acid in the Fe/oil interface in diluted suspensions can be determined by obtaining the adsorption isotherm. In addition, we present a method based on the time evolution of the optical absorbance of suspensions, from which the existence of adsorption can be inferred. For concentrated suspensions, the used of optical methods is not recommended, since they are affected by a significant inaccuracy. We present here a useful alternative based on electromagnetic induction phenomena. The results obtained allow a more comprehensive knowledge of the aggregation process in concentrated suspensions. With the same purpose, a third group of experiments, based on rheological techniques, is carried out in Fe/oil and CoNi/oil concentrated suspensions. In these series of experiments, the effect of three surfactants (oleic acid, aluminum stearate and lecithin) is tested by measuring either the viscosity, or the magnetic field-induced yield stress of the suspensions. The combination of these series of experiments gives us valuable information about the most appropriate surfactant/carrier combination capable of imparting a high stability and a strong magnetorheological response in magnetic colloids. 相似文献
364.
M. S. de la Lama I. G. Szendro J. R. Iglesias H. S. Wio 《The European Physical Journal B - Condensed Matter and Complex Systems》2006,51(3):435-442
We analyze a simple opinion formation model consisting of two
parties, A and B, and a group I, of undecided agents. We
assume that the supporters of parties A and B do not interact
among them, but only interact through the group I, and that there
is a nonzero probability of a spontaneous change of opinion (
,
). From the master
equation, and via van Kampen's Ω-expansion approach, we have
obtained the “macroscopic” evolution equation, as well as the
Fokker-Planck equation governing the fluctuations around the
deterministic behavior. Within the same approach, we have also
obtained information about the typical relaxation behavior of small
perturbations.
An erratum to this article is available at . 相似文献
365.
Elvira L Sampedro L Montero de Espinosa F Matesanz J Gómez-Ullate Y Resa P Echevarría FJ Iglesias JR 《Ultrasonics》2006,45(1-4):92-99
An eight-channel ultrasonic detecting device for microbiological quality evaluation of packed liquid foods is presented in this paper. This device makes possible a non-invasive detection of the microbial growth in liquid foods with no need to open the carton-based packages where they are contained. Thermal and humidity stabilization are required inside the measuring chamber. The changes in the liquid media produced by the microorganism growth induce variations in the ultrasonic propagation parameters giving a non-invasive evidence of the developing contamination. For that purpose, the amplitude and time of flight of an ultrasonic 800 kHz tone burst travelling through an UHT milk pack are analysed. Inoculated and sterile packs were tested to evaluate the performance of this new non-invasive ultrasonic microbiological quality sensor. 相似文献
366.
We study the realizations of certain braided vector spaces of rack type as Yetter–Drinfeld modules over a cosemisimple Hopf algebra H. We apply the strategy developed in [1] to compute their liftings and use these results to obtain the classification of finite-dimensional copointed Hopf algebras over . 相似文献
367.
J.R. Iglesias Sicardi A.K. Bhattacharjee R. Jullien B. Coqblin 《Solid State Communications》1975,16(5):499-502
A simple model based on the resonant scattering theory can explain the first-order semiconductor-to-metal transition accompanied by a change of valency in SmS. 相似文献
368.
369.
M. J. Cuesta F. Rubiera A. Arenillas M. J. Iglesias I. Suárez-Ruiz J. J. Pis 《Journal of Thermal Analysis and Calorimetry》2005,80(2):333-337
Summary Perhydrous coals are characterized by a high hydrogen content and exhibit a modified composition and physico-chemical properties in comparison with normal coals. These modifications affect the behaviour of perhydrous coals during pyrolysis and, therefore, may have an influence on the subsequent combustion process. In this work the combustibility behaviour of a series of perhydrous coals was evaluated in order to study the effect of hydrogen enrichment during the thermal treatment of the coals in an oxidant atmosphere. To this end temperature programmed combustion tests for the coals, and air isothermal (500°C) reactivity tests for their chars, were carried out in a thermogravimetric analyser. A clear relationship between the combustion behaviour of the perhydrous coals, and the aromatic to aliphatic hydrogen ratio was found. 相似文献
370.
González-Arellano C Corma A Iglesias M Sánchez F 《Chemical communications (Cambridge, England)》2005,(27):3451-3453
A new neutral dimeric gold(I) complex bearing the 1,2-bis[(2R,5R)-2,5-dimethylphospholanebenzene] [(R,R)-Me-Duphos] ligand has been synthesized which catalyzes the asymmetric hydrogenation of alkenes and imines under mild reaction conditions. 相似文献