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991.
The problem of the ageing infrastructure of urban water distribution networks and the loss of water associated with this has been one of the greatest infrastructure problems in urban areas. When a leakage is detected in the water supply network, problems arise when seeking to rehabilitate the network. Therefore, the decision problem is to choose which components to add or to improve and to maximize the benefits, which will result from the changes implemented. In addition, it is important to minimize costs, since water supply companies have limited budgets. Moreover, there are often several leakage points in the same water supply network and in the same period of analysis. Therefore, this paper puts forward a model for rehabilitating the greatest number of leakage points in a water network; it respects the constraints which a water company may have. Promethee V is used to assist the decision maker (DM) in selecting a set of feasible alternatives for rehabilitating the network from the criteria and the constraints set by the DM on the problem. For demonstration purposes, the proposed model was tested in a simulated network. 相似文献
992.
Marine bivalves (such as mussels, oysters, and clams) are widespread mollusks in coastal waters at different latitudes; due to their filter-feeding habits, they accumulate large numbers of bacteria from the harvesting waters and may act as passive carriers of human pathogens. To cope with this challenge, bivalves possess both humoral and cellular defense mechanisms with remarkably effective capabilities. The circulating cells, or hemocytes, are primarily responsible for defense against parasites and pathogens; microbial killing results from the combined action of the phagocytic process with humoral defense factors such as agglutinins (e.g., lectins), lysosomal enzymes (e.g., acid phosphatase, lysozyme), toxic oxygen intermediates, and various antimicrobial peptides. In this work, current knowledge of the mechanisms underlying the interactions between bacteria and the hemolymph components of marine bivalves is summarized. Bacterial susceptibility to hemolymph killing in different bivalve species may be a consequence of the different ability of bacterial products to attract phagocytes, the presence or absence of specific opsonizing molecules, the hemocyte capability to bind and engulf different bacteria, and the different bacterial sensitivity to intracellular killing. The role of soluble (e.g., agglutinins and opsonins) and surface-bound factors in bacterial phagocytosis by hemocytes of the most common marine bivalve species is described and the possibility that environmental temperatures and other seasonal factors may influence this process is considered. Moreover, the potential strategies used by bacteria to evade phagocytic killing by hemocytes are discussed. From the available data it is clear that several questions need further investigation; the elucidation of the factors influencing phagocytosis in bivalves and the fundamental strategies used by bacteria to escape hemolymph killing are important not only to understand bivalve immune defenses but also to explain the persistence of pathogenic bacteria in bivalve tissues and to predict the consequent impact on human health. 相似文献
993.
Flexible Electronics: A Bi‐Sheath Fiber Sensor for Giant Tensile and Torsional Displacements (Adv. Funct. Mater. 35/2017) 下载免费PDF全文
994.
Reusable Cellulose‐Based Hydrogel Sticker Film Applied as Gate Dielectric in Paper Electrolyte‐Gated Transistors 下载免费PDF全文
Inês Cunha Raquel Barras Paul Grey Diana Gaspar Elvira Fortunato Rodrigo Martins Luís Pereira 《Advanced functional materials》2017,27(16)
A new concept for reusable eco‐friendly hydrogel electrolytes based on cellulose is introduced. The reported electrolytes are designed and engineered through a simple, fast, low‐cost, and eco‐friendly dissolution method of microcrystalline cellulose at low temperature using an aqueous LiOH/urea solvent system. The cellulose solution is combined with carboxymethyl cellulose, followed by the regeneration and simultaneous ion incorporation. The produced free standing cellulose‐based electrolyte films exhibit interesting properties for application in flexible electrochemical devices, such as biosensors or electrolyte‐gated transistors (EGTs), because of their high specific capacitances (4–5 µF cm?2), transparency, and flexibility. Indium–gallium–zinc‐oxide EGTs on glass with laminated cellulose‐based hydrogel electrolytes (CHEs) as the gate dielectric are produced presenting a low working voltage (<2 V), showing an on–off current ratio (I on/off) of 106, a subthreshold swing lower than 0.2 V dec?1, and saturation mobility (μSat) reaching 26 cm2 V?1 s?1. The flexible CHE‐gated transistors on paper are also demonstrated, which operate at switching frequencies up to 100 Hz. Combining the flexibility of the EGTs on paper with the reusability of the developed CHEs is a breakthrough toward biodegradable advanced functional materials allied with disposable/recyclable and low‐cost electronic devices. 相似文献
995.
996.
Palácio SM Espinoza-Qui?ones FR Módenes AN Manenti DR Oliveira CC Garcia JC 《Water science and technology》2012,65(8):1392-1398
The aim of the present study was to optimise the photocatalytic degradation of a mixture of six commercial azo dyes, by exposure to UV radiation in an aqueous solution containing TiO(2)-P25. Response surface methodology, based on a 3(2) full factorial experimental design with three replicates was employed for process optimisation with respect to two parameters: TiO(2) (0.1-0.9 g/L) and H(2)O(2) (1-100 mmol/L). The optimum conditions for photocatalytic degradation were achieved at concentrations of 0.5 g TiO(2)/L and 50 mmol H(2)O(2)/L, respectively. Dye mineralisation was confirmed by monitoring TOC, conductivity, sulfate and nitrate ions, with a sulfate ion yield of 96% under optimal reactor conditions. Complete decolorisation was attained after 240 min irradiation time for all tested azo-dyes, in a process which followed a pseudo-first kinetic order model, with a kinetic rate constant of approximately 0.018 min(-1). Based on these results, this photocatalytic process has promise as an alternative for the treatment of textile effluents. 相似文献
997.
Elisa Guerrieri Simona de Niederhäusern Patrizia Messi Carla Sabia Ramona Iseppi Immacolata Anacarso Moreno Bondi 《Food Control》2009,20(9):861-865
The antilisterial activity in biofilms developed in a small-scale model by two LAB (lactic acid bacteria) bacteriocin producers (Lactobacillus plantarum 35d, Enterococcus casseliflavus IM 416K1) and by two non-producers (L. plantarum 396/1, Enterococcus faecalis JH2-2) was evaluated against Listeria monocytogenes NCTC 10888. The LAB biofilms showed the capability to influence the survival and the multiplication of the pathogen with differences among the strains. L. plantarum 35d displayed the highest efficacy reducing L. monocytogenes by 5.4 log in the planktonic population and by 3.9 log in the adherent population at the end of the experiment (10 days). L. plantarum 396/1 reduced L. monocytogenes by 3.8 log in the adherent cells and by 4.9 log in the planktonic cells and this outcome could be attributed to the pH reduction.The E. casseliflavus IM 416K1 biofilm caused a L. monocytogenes reduction of 3.7 log in the adherent cells and of 4.8 log in the planktonic cells and the role of the bacteriocin production seemed to be predominant as the pH values did not significantly decrease. This hypothesis is confirmed by a slight capability to influence the L. monocytogenes survival by the non-bacteriocinogenic E. faecalis JH2-2. Studies performed with L. monocytogenes in co-culture with a Pseudomonas putida strain, revealed a reduction of the antilisterial activity only for the biofilms produced by lactobacilli. 相似文献
998.
999.
Julie Ann Kemp Marta Esgalhado Renata Azevedo Macedo Bruna Regis Ngila Raquel Teixeira Damasceno Elizabeth Aparecida Ferraz da Silva Torres Gustavo Henrique Ferreira Gonalinho Natlia Alvarenga Borges Lia Sumie Nakao Denis Fouque Denise Mafra 《Hemodialysis international. International Symposium on Home Hemodialysis》2019,23(2):189-197
1000.
Ana M. Borreguero Juan F. Rodríguez José Luis Valverde Raquel Arevalo Ton Peijs Manuel Carmona 《Journal of Materials Science》2011,46(2):347-356
Catalyst Tegoamin 33 has been used for the synthesis of rigid polyurethane (RPU) foams containing microencapsulated Rubitherm® RT27 and having a high mechanical resistance. These materials could be employed in buildings for thermal insulation and thermal energy storage (TES). The fillers content influence on the foaming process and also the foam properties was evaluated. It was observed that a foam containing up to a 18 wt% of microcapsules can be manufactured, improving the TES capacity while maintaining the mechanical properties of the neat foam. Besides, it was observed that the mechanical resistance of foams synthesized using catalyst Tegoamin 33 are higher than those obtained when catalyst Tegoamin BDE was employed, with the mechanical resistance of the foam containing 21 wt% being higher than those of foams synthesized with catalyst BDE containing only 11 wt% of fillers while maintaining the advantages of an improvement in TES capacity. A general model of reaction curve of n tank-in-series of a same time constant was used to fit the rising curves. This model allowed to predict the final volume of the synthesized foam. Finally, TES capacities and mechanical properties of the synthesized foams were in the range of those reported in literature. Moreover, foam densities satisfied the restriction established by the Spanish regulation for building applications. 相似文献