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P. Cañizares J. Lobato J. García-Gómez M.A. Rodrigo 《Journal of Applied Electrochemistry》2004,34(1):111-117
This paper describes a combined adsorption/electrochemical reaction device for the treatment of acidic aqueous phenol wastes. The system works in batch mode. In each operation cycle there are two stages: (i) treatment of waste, in which the organic matter contained in the waste is removed from the aqueous solution and (ii) activated carbon regeneration, in which adsorbed organics are removed from the system and converted into carbon dioxide. The system leads to successful treatment of these wastes and transforms the organics contained in the waste into carbon dioxide and electrocoagulated solids. The granular activated carbon (GAC) bed of the system achieves rapid removal of the organics, with treatment time shorter than those reported for conventional electrochemical treatments. The regeneration of the GAC is achieved by electrochemical means and efficiencies close to 80% are obtained. The energy consumption of this system is similar to those reported for other electrochemical technologies used to treat aqueous wastes. 相似文献
134.
Miguel Angel Lpez‐Manchado Marcela Valle Rodrigo Sapunar Raúl Quijada 《应用聚合物科学杂志》2004,92(5):3008-3015
The properties of two new ethylene‐α‐olefin copolymers, namely, ethylene–1‐hexene copolymer (EHC) and ethylene–1‐octadecene copolymers (EOC), synthesized via metallocene catalysts were evaluated. The copolymerization was carried out in an autoclave reactor with Et(Indenyl)2ZrCl2/methylaluminoxane as a catalyst system. These single‐site catalysts (metallocene type) allow one to obtain very homogeneous copolymers with excellent control of the molecular weight distribution and proportion of comonomer incorporation. So, copolymers with 18 mol % comonomer in the case of EHC and 12 mol % for EOC were shaped, and activities around 100,000 kg of polymer mol?1 of Zr bar?1 h?1 were reached. The properties of these copolymers were compared with other commercial elastomers, such as ethylene–propylene copolymers synthesized by Ziegler–Natta catalysts and an ethylene–octene copolymer obtained via metallocene catalysts. The results show that these new copolymers, in particular, EOC, had excellent elastomeric properties. Furthermore, they had a relatively low viscosity, which implied a good response during processing. Moreover, the effectiveness of these copolymers as impact modifiers for polyolefins was also studied. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 3008–3015, 2004 相似文献
135.
Nelly Abigail Rodríguez Efrain Almanza María de Jesús Pérez Carlos Rodrigo Mu?iz Scott Packer Russell Steel 《Frontiers of Materials Science in China》2010,4(4):415-419
This study evaluates the degree of sensitization (DOS) of 304 stainless steel joined by friction stir welding (FSW). Single-loop electrochemical potentiokinetic reactivation tests were performed using a 0.5 mol/L H2SO4 + 0.01 mol/L KSCN solution. Sensitization was promoted by exposition of the stainless steel at temperatures between 400°C and 850°C. The microstructure was characterized using optical microscopy to identify the weld zone and the base metal. The samples treated at 550°C showed the most severe intergranular corrosion. The DOS was lower in the weld zone than in the base metal after heat treatments. This reduction in the DOS for the weld zone indicates that FSW is a beneficial process in joining stainless steel. 相似文献
136.
In component-based development, software components are taken as units of composition. Nevertheless, to achieve the widely disseminated status of components being plugged together as simple ‘Lego Pieces’, the integration of components must be carefully designed, systematised and verified; only this can ensure reliable architectures. In this work, we propose some conformance notions to predict the precise nature of some forms of composition, considering coordination patterns used in the integration. These notions are formalised in terms of the denotational semantics of the process algebra CSP, and assist the designer in common activities during integration, such as the substitution of component specifications by implementations, contract adaptations, and system extensions. To support mechanical verifications using FDR (a model-checker for CSP), we derive test characterisations from the denotational definitions of conformance. We illustrate the application of these notions through a systematic composition strategy of software frameworks, and we mechanically verify the preservation of behavioural component properties in these compositions. Moreover, we characterise the well-formedness of a coordination pattern used in this strategy at the design stage, before components are assembled. 相似文献
137.
Glaucio H. Paulino Kyoungsoo Park Waldemar Celes Rodrigo Espinha 《International journal for numerical methods in engineering》2010,84(11):1303-1343
Dependence on mesh orientation impacts adversely the quality of computational solutions generated by cohesive zone models. For instance, when considering crack propagation along interfaces between finite elements of 4k structured meshes, both extension of crack length and crack angle are biased according to the mesh configuration. To address mesh orientation dependence in 4k structured meshes and to avoid undesirable crack patterns, we propose the use of nodal perturbation (NP) and edge‐swap (ES) topological operation. To this effect, the topological data structure TopS (Int. J. Numer. Meth. Engng 2005; 64 : 1529–1556), based on topological entities (node, element, vertex, edge and facet), is utilized so that it is possible to access adjacency information and to manage a consistent data structure in time proportional to the number of retrieved entities. In particular, the data structure allows the ES operation to be done in constant time. Three representative dynamic fracture examples using ES and NP operators are provided: crack propagation in the compact compression specimen, local branching instability, and fragmentation. These examples illustrate the features of the present computational framework in simulating a range of physical phenomena associated with cracking. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
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O. Martínez-Matos J. A. Rodrigo M. L. Calvo V. Hevia-Martín P. Cheben 《Optical Memory & Neural Networks》2009,18(1):21-24
The properties of a photopolymerizable glass modified with high refractive index species incorporated at molecular level,
including a wide range of spatial frequencies and the recording kinetics, are analyzed. Implementation of emerging applications
is proposed.
The article is published in the original. 相似文献