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21.
Tânia F.C.V. Silva M. Elisabete F. Silva A. Cristina Cunha-Queda Amélia Fonseca Isabel Saraiva M.A. Sousa C. Gonçalves M.F. Alpendurada Rui A.R. Boaventura Vítor J.P. Vilar 《Water research》2013
A multistage treatment system, at a scale close to the industrial, was designed for the treatment of a mature raw landfill leachate, including: a) an activated sludge biological oxidation (ASBO), under aerobic and anoxic conditions; b) a solar photo-Fenton process, enhancing the bio-treated leachate biodegradability, with and without sludge removal after acidification; and c) a final polishing step, with further ASBO. 相似文献
22.
Felipe R. Boni Filipe V. Ferreira Ivanei F. Pinheiro Silvana A. Rocco Mauricio L. Sforça Liliane M. F. Lona 《应用聚合物科学杂志》2020,137(45):49416
Here, an alternative route to successfully synthesize polystyrene-block-poly(methyl methacrylate) (PS-b-PMMA) is reported. Steglich esterification was used as an effective, metal free approach for coupling carboxylic terminated PS and the hydroxyl end-functionalized PMMA chains obtained by nitroxide-mediated polymerization and atom transfer radical polymerization, respectively. α-Functionalization was obtained using 4,4′-azobis(4-cyanovaleric acid) and 2,2,2-tribromoethanol as initiators. The synthesis of PS-b-PMMA was confirmed by gel permeation chromatography and nuclear magnetic resonance (NMR), while the dependence of the diffusion coefficients of the polymers (PS, PMMA, PS/PMMA blend, and PS-b-PMMA) with their corresponding molecular weights was discussed based on the results of atomic force microscopy-based infrared spectroscopy, differential scanning calorimetry, and spectra of diffusion-ordered NMR spectroscopy. Differently from PS-b-PMMA, a partial segregation was observed for the PS/PMMA blend, affecting its thermal behavior and diffusion coefficient. The study here presented provides an easier and efficient strategy for the synthesis of PS-b-PMMA and new insights into the diffusion of polymers. 相似文献
23.
Luís Filipe Sanches Fernandes Maria João Marques Paula Cristina Oliveira João Paulo Moura 《Water and Environment Journal》2014,28(3):350-357
This paper puts forward the importance of decision support systems (DSS) for the planning and management of water resources. A case study of the Pinhão river basin, in Portugal, is presented. Given the importance of vineyards in the Douro region, it is important to determine if water availability will be enough to meet present and future water demands. In order to answer this question, DSS tools were used to assess different scenarios. The MIKE BASIN software was used in the hydrographical basin of Pinhão river, assisted by a geographic information system, GIS, which allowed the modelling of the basin, both temporally and spatially, facilitating the visualisation and interpretation of results. According to the attained results, it was verified that, at present, the hydrographical basin meets the considered water needs. The DSS proved to be an important tool to assist the decision‐making process in the studied river basin. 相似文献
24.
A localized Delaunay triangulation owns the following interesting properties for sensor and wireless ad hoc networks: it can
be built with localized information, the communication cost imposed by control information is limited, and it supports geographical
routing algorithms that offer guaranteed convergence. This paper presents two localized algorithms, fast localized Delaunay
triangulation 1 (FLDT1) and fast localized Delaunay triangulation 2 (FLDT2), that build a graph called planar localized Delaunay
triangulation, PLDel, known to be a good spanner of the Unit Disk Graph, UDG. Our algorithms improve previous algorithms with similar theoretical bounds in the following aspects: unlike previous work,
FLDT1 and FLDT2 build PLDel in a single communication step, maintaining a communication cost of O(n log n), which is within a constant of the optimal. Additionally, we show that FLDT1 is more robust than previous triangulation
algorithms, because it does not require the strict UDG connectivity model to work. The small signaling cost of our algorithms allows us to improve routing performance, by efficiently
using the PLDel graph instead of sparser graphs, like the Gabriel or the Relative Neighborhood graphs. 相似文献
25.
Inês Portugal Susana C. Ribeiro Ana M.R.B. Xavier Filipe Centeno Pierre Strehaiano 《International Journal of Food Science & Technology》2011,46(2):284-289
Maloalcoholic fermentation (MAF) of grape must by Schizosaccharomyces pombe immobilised in calcium‐alginate double‐layer beads (ProMalic®) was studied in Erlenmeyer flasks and in a total recycle fixed‐bed reactor operating in batch mode. The reaction is pseudo‐first order with respect to l ‐malic acid and under similar conditions deacidification is faster in the recycle reactor. This was attributed to mass transfer limitations which were confirmed in the recycle reactor by studying the influence of yeast load on the rate of MAF. Mass transfer limitations are also responsible for the lower activation energy of fermentation with the immobilised yeast (67 ± 9 kJ mol?1) in comparison with the free cells (126 ± 19 kJ mol?1). Alcoholic fermentation and MAF were performed simultaneously, both in the recycle reactor and in the industrial trials, confirming the efficacy of immobilised S. pombe to reduce grape must acidity without interfering with the main fermentation. Altogether, the present results are useful for the scale‐up of a recycle reactor to process large volumes of grape must. 相似文献
26.
Pedro Santarém Andrade António Almeida Saraiva 《Bulletin of Engineering Geology and the Environment》2010,69(2):207-214
This work defines the physical and mechanical characteristics of phyllites and metagreywackes belonging to a schist–greywacke
complex in central Portugal. The index properties, point load strength, uniaxial compressive strength, slake durability and
Schmidt rebound hardness were determined. In general, the metagreywackes gave a higher strength than phyllites with the same
weathering degree. Possible correlations and estimation models were established and compared with the equations obtained by
different researchers. 相似文献
27.
Ana S.V. FerreiraCátia M.C. Soares Filipe M.H.L.R. FigueiredoFernando M.B. Marques 《International Journal of Hydrogen Energy》2011,36(5):3704-3711
Composite ionic conductors for fuel cells were produced by combination of one ceria-based ceramic electrolyte and various mixtures of Na and Li carbonates, using several processing routes. These materials were characterized by impedance spectroscopy, scanning electron microscopy with energy dispersive spectroscopy, X-ray diffraction and Fourier transform infrared spectroscopy with attenuated total reflectance. The chemical composition of the mixed carbonates and the processing route were influential in the development of impressive conductivity levels (close to 0.1 S/cm) at modest temperatures (below 600 °C), suggesting a complex role of chemical composition (Na/Li ratio), phase composition (solid/liquid ratio), processing route (mechanothermal history) and microstructure. Furthermore, exposure to humidity showed formation of OH groups. Such hydrogenated species are believed to increase the complexity of the global surface processes and charge transport mechanisms where several native and foreign species may play a significant role. 相似文献
28.
Filipe Valente Alberto Vale Daniel Fonte Isabel Ribeiro 《Fusion Engineering and Design》2011,86(9-11):1967-1970
The transfer cask system (TCS) is one of the remote handling systems that will operate in ITER, transporting heavy and highly activated in-vessel components between the tokamak building and the hot cell building. A motion planning methodology for the TCS was developed, providing smooth paths that maximize the clearance to obstacles and that incorporate manoeuvres whenever necessary. This paper presents the results of the TCS planning algorithm with trajectories computed for nominal operations. The length of the journey, the velocity, the time duration, and the risk of collision were evaluated individually for each trajectory. A summary of all results, conclusions and future work are presented and discussed. 相似文献
29.
In this text we present the real-time implementation of a Bayesian framework for robotic multisensory perception on a graphics
processing unit (GPU) using the Compute Unified Device Architecture (CUDA). As an additional objective, we intend to show
the benefits of parallel computing for similar problems (i.e. probabilistic grid-based frameworks), and the user-friendly
nature of CUDA as a programming tool. Inspired by the study of biological systems, several Bayesian inference algorithms for
artificial perception have been proposed. Their high computational cost has been a prohibitory factor for real-time implementations.
However in some cases the bottleneck is in the large data structures involved, rather than the Bayesian inference per se.
We will demonstrate that the SIMD (single-instruction, multiple-data) features of GPUs provide a means for taking a complicated
framework of relatively simple and highly parallelisable algorithms operating on large data structures, which might take up
to several minutes of execution with a regular CPU implementation, and arrive at an implementation that executes in the order
of tenths of a second. The implemented multimodal perception module (including stereovision, binaural sensing and inertial
sensing) builds an egocentric representation of occupancy and local motion, the Bayesian Volumetric Map (BVM), based on which
gaze shift decisions are made to perform active exploration and reduce the entropy of the BVM. Experimental results show that
the real-time implementation successfully drives the robotic system to explore areas of the environment mapped with high uncertainty. 相似文献
30.