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991.
Hugo M. Santos Bruno Pedras Abel Tamayo Jaume Casabó Lluis Escriche Berta Covelo José Luis Capelo Carlos Lodeiro 《Inorganic chemistry communications》2009,12(11):1128-1134
Two new emissive chemosensors based on coumarin-343 have been synthesized, and their photophysical studies conducted. L1 contains an aza-thio macrocycle ring as the chelating unit, which has great affinity for soft metal ions, whereas L2 is a parent species without macrocyclic unit. Both compounds were separated by column chromatography and characterized by elemental analysis, 1H,13C NMR, UV–vis and FAB mass spectroscopy. The X-ray structures of L1 and L2 and the supramolecular interactions in the solid state are discussed. Preliminary results on the metal–ion sensing effects of the ligands are presented. Titrations with Ag+, Pd2+ and Ni2+ have been studied by UV–vis absorption and fluorescence spectroscopy. 相似文献
992.
María J. Martín de Vidales José Robles‐Molina Juan C. Domínguez‐Romero Pablo Cañizares Cristina Sáez Antonio Molina‐Díaz Manuel A. Rodrigo 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2012,87(10):1441-1449
BACKGROUND: Sulfamethoxazole (SMX, used as a model bacteriostatic antibiotic) is persistent to conventional biological treatments of wastewaters. In this work, conductive‐diamond electrochemical oxidation (CDEO) was found to be an effective technology for its removal from the effluents of conventional wastewater treatment plants. RESULTS: The use of CDEO has been evaluated for the removal of the antibiotic SMX from water and wastewaters. The results show that CDEO can reduce the concentration of this organic pollutant to values below 0.1 µg dm?3. The variation of the SMX concentration during electrolysis shows a complex shape with a plateau zone that increases in size with the initial concentration of SMX. This complex trend is not observed in the changes of TOC, which seems to indicate that the CDEO of SMX solutions does not lead directly to the generation of carbon dioxide as a final product. A tentative reaction pathway has been proposed based on a thorough analysis of the reaction mixture, in which the main intermediate products were identified. The use of liquid chromatography time‐of‐flight mass spectrometry (LC‐TOFMS) allowed the identification of nine organic intermediates (with Mw 98, 108, 172, 173, 197, 203, 227, 269 and 287) during the electrolysis and the concentration of these compounds depends on the initial SMX concentration and on the current density applied. CONCLUSIONS: CDEO is able to reduce the concentration of the organic pollutant below 0.1 mg dm?3. SMX removal is faster than that of TOC. This fact indicates the formation of reaction intermediates. Analytical techniques show that nine reaction intermediates are generated in the system, and that their concentration depends on the initial SMX concentration and on the current density used. Copyright © 2012 Society of Chemical Industry 相似文献
993.
Federico Cismondi Abigail L. Horn André S. Fialho Susana M. Vieira Shane R. Reti João M.C. Sousa Stan Finkelstein 《Expert systems with applications》2012,39(16):12332-12339
In many binary medical classification problems, the cost of misclassifying one category is higher than the other, and in these applications it is desirable to employ a classifier with selective sensitivity or specificity. This work explores the utility of a fuzzy multi–criteria function for performance evaluation during knowledge–based medical classification and prediction. The method presented here uses fuzzy optimization to combine the sensitivity, specificity, and accuracy of classification as goals in a single objective function. This approach is used to assign flexible goals, which can be used to maximize the outcome in terms of each one of the goals. The proposed approach significantly increases the sensitivity and the specificity while maintaining or increasing accuracy. The versatility of the method is further exploited in a multi-model approach, using individual structures of multi-objective optimization of sensitivity and specificity separately, and then combining their outcomes through a decision-making module. Among various medical benefits derived from applying this technique, the divergent feature sets selected by high sensitivity and specificity models lend insight into factors more integrally connected to what causes risk of death for patients. 相似文献
994.
995.
Paulo E. Laranjeira António A. Martins José Carlos B. Lopes Madalena M. Dias 《American Institute of Chemical Engineers》2009,55(9):2226-2243
NETmix® is a new technology for static mixing based on a network of chambers connected by channels. The NETmix® model is the basis of a flow simulator coupled with chemical reaction used to characterize macro and micromixing in structured porous media. The chambers are modeled as perfectly mixing zones and the channels as plug flow perfect segregation zones. A segregation parameter is introduced as the ratio between the channels volume and the whole network volume. Different kinetics and reactants injection schemes can be implemented. Results show that the number of rows in the flow direction and the segregation parameter control both macro and micromixing, but the degree of micromixing is also controlled by the reactants injection scheme. The NETmix® model enables the systematic study of micromixing and macromixing for different network structures and reaction schemes, enabling the design of network structures to ensure the desired yield and selectivity. © 2009 American Institute of Chemical Engineers AIChE J, 2009 相似文献
996.
Maneuver prediction for road vehicles based on a novel neuro-fuzzy dynamic architecture 总被引:1,自引:0,他引:1
Ana Toledo Rafael Toledo-Moreo José Manuel Cano-Izquierdo Miguel Pinzolas-Prado 《Robotics and Autonomous Systems》2010,58(12):1316-1320
Collision avoidance systems for road vehicles may benefit from timely predictions of vehicle maneuvers. This article presents a novel approach for the prediction of maneuvers that copes with noisy measurements and is based on a supervised version of a dynamic FasArt method (SdFasArt). Additionally, the use of size-dependent scatter matrices to compute the activation of the neurons makes the algorithm more adaptable to different data distributions. The results obtained in real tests confirm the goodness of the method. 相似文献
997.
M. Carmen Clemente Fernando Ruiz-Vega Pablo Otero José F. Paris 《Wireless Personal Communications》2014,78(2):1231-1248
In this paper the performance of a wireless communications system over shallow underwater acoustic channels is investigated when adaptive modulation and coding techniques with receiver diversity are used. It is assumed that the communication system experiences Ricean shadowed fading. We obtain the analytical figures of the proposed rate-adaptive transmission schemes, emphasizing in the spectral efficiency and the average bit error rate. These analytical expressions are compared to Monte-Carlo simulations corroborating the analytical results. 相似文献
998.
José Ramón Gállego Ángela Hernández Israel Guío Antonio Valdovinos 《Telecommunication Systems》2010,43(3-4):279-294
In this paper, a comparative analysis of the performance of the nonsynchronized initial random access channel in Mobile WiMAX and E-UTRA systems under different conditions (fast fading, multiuser interference) is carried out. The analysis is focused on the correlation properties of the code sequences used in each case. We evaluate their ability to provide low values for false alarm and erroneous detection probabilities (detecting a sequence that has not been transmitted) at the same time as guaranteeing low nondetection probabilities of the effectively transmitted sequences. Results show the promising performance of the E-UTRA scheme, even in high mobility scenarios, where the Doppler effect requires additional considerations to guarantee the correct system operation. 相似文献
999.
1000.
Carpintero Helio; Lafuente Enrique; Quintana José; Ruiz Gabriel; Sáiz Dolors; Sáiz Milagros; Sánchez Natividad 《Canadian Metallurgical Quarterly》2010,13(3):277
History of Psychology has been an extremely active field for many years in Spain. Both the great expansion of psychological studies and the inclusion of history as a compulsory subject in the psychology curriculum are crucial factors helping to understand the current state of affairs. The aim of this paper is to provide a survey of the work done in this area over the last decade, covering research, teaching, and institutional developments. The study includes consideration of aspects such as main research lines, major theoretical and methodological trends, teaching materials, relevant archives and exhibits, and significant websites. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献