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41.
Manganese ferrite nanoparticles synthesized through a nanocasting route as a highly active Fenton catalyst 总被引:2,自引:0,他引:2
Teresa Valds-Solís Patricia Valle-Vign Sonia lvarez Gregorio Marbn Antonio B. Fuertes 《Catalysis communications》2007,8(12):2037-2042
Spinel ferrite MnFe2O4 nanoparticles were synthesized by means of a nanocasting technique using a low-cost mesoporous silica gel as a hard template. The magnetic nanoparticles, of <10 nm diameter and with a surface area of around 100 m2/g, were tested as a heterogeneous Fenton catalyst for the decomposition of hydrogen peroxide under neutral and basic conditions. This catalyst shows a much higher activity than previous heterogeneous catalysts reported in the literature, which is mainly ascribed to its small particle size. Furthermore, the magnetic catalyst can be easily separated from the reaction medium by means of an external magnetic field. The effects of residual silica and the purity of the catalyst (hematite formation) on catalytic activity have been studied and correlated. The results obtained show this catalyst to be a suitable candidate for the removal of pollutants in wastewaters by means of the Fenton heterogeneous reaction. 相似文献
42.
Noemí de-los-Santos-Álvarez 《Electrochimica acta》2007,53(2):829-836
We have studied the potential electrocatalytic activity towards the oxidation of NADH of several oxidation products of guanine and its derivative guanosine-5′-monophosphate (5′-GMP) on pyrolytic graphite electrodes (PGE). The distribution of products generated strongly depends on the experimental conditions. Our investigations focused on the oxidation products that are adsorbed on the electrode surface, are redox active and, exhibited electrocatalytic activity toward the oxidation of NADH. These compounds were electrochemically and kinetically characterized in terms of dependence of the formal potential on pH and electron transfer rate constant (ks). The voltammetric and catalytic behavior of both guanine and 5′-GMP oxidation products was compared with that of other guanine derivatives we have previously studied. Some mechanistic aspects concerning the generation of the catalysts are also discussed. 相似文献
43.
Alejandro Ávila-Ortega José Pablo Avalos-Hernández Rudy Trejo-Tzab Andrés Iván Oliva Juan Antonio Juárez-Moreno 《应用聚合物科学杂志》2021,138(30):50737
Among several oil/water emulsion separation technologies, the utilization of nanoparticle-decorated membranes with diverse functionalities has received considerable attention in recent years, particularly if the antifouling capacity can be improved. In this article, we propose a new membrane based on surface-hydrolyzed polyacrylonitrile electrospun membranes and/or decorated with amine-functionalized Si-MCM-41 nanoparticles to be used as oil/water emulsion separation treatment and to determine their antifouling ability. X-Ray photoelectron spectrometry, attenuated total reflectance Fourier transform infrared spectroscopy, and toluidine blue O assay, scanning electron microscopy, contact angle measurements for oil under water and thermogravimetry were used for characterizing the membranes and an assay of permeability was developed to quantify the diffusion of oil molecules across the electrospun membrane. The electrospun and/or decorated membranes showed an underwater oleophobic wettability, which can separate oil-in-water emulsions with 87% separation efficiency, results of fouling experiments, evaluated in terms of rejection and flux recovery ratio, exhibited good antifouling ability, but the membrane decoration process did not lead to superior outcomes compared with undecorated membranes. 相似文献
44.
45.
G. Asencio-Cortés E. Florido A. Troncoso F. Martínez-Álvarez 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2016,20(11):4205-4216
Urban traffic congestion prediction is a very hot topic due to the environmental and economical impacts that currently implies. In this sense, to be able to predict bottlenecks and to provide alternatives to the circulation of vehicles becomes an essential task for traffic management. A novel methodology, based on ensembles of machine learning algorithms, is proposed to predict traffic congestion in this paper. In particular, a set of seven algorithms of machine learning has been selected to prove their effectiveness in the traffic congestion prediction. Since all the seven algorithms are able to address supervised classification, the methodology has been developed to be used as a binary classification problem. Thus, collected data from sensors located at the Spanish city of Seville are analyzed and models reaching up to 83 % are generated. 相似文献
46.
The provision of support for holistic operations in the scope of a horizontal digital administration requires the fulfillment of a number of previous steps that guarantee the viability of services in the domain. One of these tasks is the proper management of documents. Documents are a key element of any democratic administration and their digital management is a clear pre-requisite for the arrival of digital government. This article tackles how this service can be provided using the support of semantics as a technological cornerstone. The implementation of such a tool is made through the so-called cPortfolio. This platform is deeply discussed and details about its design and implementation are provided. This system is designed to manage both the personal information from the citizen and the documents they possess. Tests on the prototype showed interesting features regarding the simplicity of use and the interoperability support provided to third party agents. 相似文献
47.
Álvaro Rubio-Largo Miguel A. Vega-Rodríguez Juan A. Gómez-Pulido Juan M. Sánchez-Pérez 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2013,17(2):199-211
Nowadays, the most promising technology for designing optical networks is the wavelength division multiplexing. This technique divides the huge bandwidth of an optical fiber link into different wavelengths, providing different available channels per link. However, a problem comes up when it is necessary to interconnect a set of traffic demands. This problem is known as routing and wavelength assignment problem, and due to its complexity (NP-hard problem) it is very suitable for being solved using evolutionary computation. The selected heuristics is the artificial bee colony algorithm, an heuristics based on the behavior of honeybee foraging for nectar. Therefore, we have applied multiobjective optimization to solve the static routing and wavelength assignment problem, and adapted this algorithm to the multiobjective context. New results have been obtained that significantly improve those published in previous researches. 相似文献
48.
49.
One of the applications of workflow systems is the management of administrative processes characterized by the transmission
of information elements among users of an organization. Tasks contained in these processes are carried out by users responsible
for confirming, modifying or adding information throughout. These processes need to be defined in workflow management systems
in which all the elements are perfectly identified and are easily adaptable to changes that may arise in the sequences of
tasks, in the users involved or in the data transmitted from one task to another. For this kind of processes is easier to
reuse those represented in ontologies. On one hand, existing ontologies for representing some domain elements can be reused.
At the same time, ontologies have an excellent expressive capacity to define tasks, their relationships and the flow control
among them with precision. This paper proposes a complete model, together with the necessary software tools, for tackling
this issue.
álvaro E. Prieto is a teaching/research assistant professor of Computer Science at the University of Extremadura, Spain. He has an MSc in Computer Science from the University of Extremadura (2000). His Ph.D. research addresses the use of ontologies in workflows. He is currently involved in various national and regional R&D&I projects. Adolfo Lozano-Tello is teaching/research assistant professor of Computer Science Department at University of Extremadura, Spain. He is a Ph.D. (2002) with a special prize of extraordinary thesis about selection of ontologies for software applications. He has published more than 50 papers on the above issues on Software Engineering and Knowledge Engineering. 相似文献
álvaro E. PrietoEmail: |
álvaro E. Prieto is a teaching/research assistant professor of Computer Science at the University of Extremadura, Spain. He has an MSc in Computer Science from the University of Extremadura (2000). His Ph.D. research addresses the use of ontologies in workflows. He is currently involved in various national and regional R&D&I projects. Adolfo Lozano-Tello is teaching/research assistant professor of Computer Science Department at University of Extremadura, Spain. He is a Ph.D. (2002) with a special prize of extraordinary thesis about selection of ontologies for software applications. He has published more than 50 papers on the above issues on Software Engineering and Knowledge Engineering. 相似文献
50.
GN Kremenchutski? ML Gorbunova LG Iurgel' VI Chu?ko SA Cherniaev 《Canadian Metallurgical Quarterly》1994,56(4):36-42
The paper deals with the data on biology of Aerococcus, a slightly studied group of microorganisms. Physiological-biochemical properties of Aerococcus are described, data of their distribution in nature are given. Peculiar attention is paid to the estimate of the role of Aerococcus in human microbiocenoses. As a result of the profound and all-round study of this group of microorganisms the authors have developed new bacterial drug "A-bakterin" based on the aerococcus strain. Data presented about the results of clinical tests of "A-bakterin" are presented, a possibility to use Aerococcus lysate in the elaboration of new drugs is discussed. 相似文献