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Author (up) Jungles, M.K.; Val del Rio, A.; Mosquera-Corral, A.; Campos, J.L.; Mendez, R.; Costa, R.H.R.
Title Effects of Inoculum Type and Aeration Flowrate on the Performance of Aerobic Granular SBRs Type
Year 2017 Publication Processes Abbreviated Journal Processes
Volume 5 Issue 3 Pages 10 pp
Keywords aeration flowrate; aerobic granules; inoculum; sequencing batch reactor; wastewater
Abstract Aerobic granular sequencing batch reactors (SBRs) are usually inoculated with activated sludge which implies sometimes long start-up periods and high solids concentrations in the effluent due to the initial wash-out of the inoculum. In this work, the use of aerobic mature granules as inoculum in order to improve the start-up period was tested, but no clear differences were observed compared to a reactor inoculated with activated sludge. The effect of the aeration rate on both physical properties of granules and reactor performance was also studied in a stable aerobic granular SBR. The increase of the aeration flow rate caused the decrease of the average diameter of the granules. This fact enhanced the COD and ammonia consumption rates due to the increase of the DO level and the aerobic fraction of the biomass. However, it provoked a loss of the nitrogen removal efficiency due to the worsening of the denitrification capacity as a consequence of a higher aerobic fraction.
Address [Jungles, Mariele K.; Costa, Rejane H. R.] Fed Univ Santa Catarina UFSC, CTC, ENS, Dept Sanit & Environm Engn, BR-88010970 Florianopolis, SC, Brazil, Email: marielejungles@hotmail.com;
Corporate Author Thesis
Publisher Mdpi Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2227-9717 ISBN Medium
Area Expedition Conference
Notes WOS:000412051700009 Approved
Call Number UAI @ eduardo.moreno @ Serial 944
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Author (up) Munoz, V.; Asenjo, F.A.; Dominguez, M.; Lopez, R.A.; Valdivia, J.A.; Vinas, A.; Hada, T.
Title Large-amplitude electromagnetic waves in magnetized relativistic plasmas with temperature Type
Year 2014 Publication Nonlinear Processes In Geophysics Abbreviated Journal Nonlinear Process Geophys.
Volume 21 Issue 1 Pages 217-236
Keywords
Abstract Propagation of large-amplitude waves in plasmas is subject to several sources of nonlinearity due to relativistic effects, either when particle quiver velocities in the wave field are large, or when thermal velocities are large due to relativistic temperatures. Wave propagation in these conditions has been studied for decades, due to its interest in several contexts such as pulsar emission models, laser-plasma interaction, and extragalactic jets. For large-amplitude circularly polarized waves propagating along a constant magnetic field, an exact solution of the fluid equations can be found for relativistic temperatures. Relativistic thermal effects produce: (a) a decrease in the effective plasma frequency (thus, waves in the electromagnetic branch can propagate for lower frequencies than in the cold case); and (b) a decrease in the upper frequency cutoff for the Alfven branch (thus, Alfven waves are confined to a frequency range that is narrower than in the cold case). It is also found that the Alfven speed decreases with temperature, being zero for infinite temperature. We have also studied the same system, but based on the relativistic Vlasov equation, to include thermal effects along the direction of propagation. It turns out that kinetic and fluid results are qualitatively consistent, with several quantitative differences. Regarding the electromagnetic branch, the effective plasma frequency is always larger in the kinetic model. Thus, kinetic effects reduce the transparency of the plasma. As to the Alfven branch, there is a critical, nonzero value of the temperature at which the Alfven speed is zero. For temperatures above this critical value, the Alfven branch is suppressed; however, if the background magnetic field increases, then Alfven waves can propagate for larger temperatures. There are at least two ways in which the above results can be improved. First, nonlinear decays of the electromagnetic wave have been neglected; second, the kinetic treatment considers thermal effects only along the direction of propagation. We have approached the first subject by studying the parametric decays of the exact wave solution found in the context of fluid theory. The dispersion relation of the decays has been solved, showing several resonant and nonresonant instabilities whose dependence on the wave amplitude and plasma temperature has been studied systematically. Regarding the second subject, we are currently performing numerical 1-D particle in cell simulations, a work that is still in progress, although preliminary results are consistent with the analytical ones.
Address [Munoz, V.; Dominguez, M.; Lopez, R. A.; Valdivia, J. A.] Univ Chile, Fac Ciencias, Dept Fis, Santiago, Chile, Email: vmunoz@fisica.ciencias.uchile.cl
Corporate Author Thesis
Publisher Copernicus Gesellschaft Mbh Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1023-5809 ISBN Medium
Area Expedition Conference
Notes WOS:000332337700017 Approved
Call Number UAI @ eduardo.moreno @ Serial 360
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Author (up) Pabon-Pereira, C.P.; Hamelers, H.V.M.; Matilla, I.; van Lier, J.B.
Title New Insights on the Estimation of the Anaerobic Biodegradability of Plant Material: Identifying Valuable Plants for Sustainable Energy Production Type
Year 2020 Publication Processes Abbreviated Journal Processes
Volume 8 Issue 7 Pages 23 pp
Keywords anaerobic digestion; biodegradability; lignocellulosics; fiber degradation
Abstract Based on fifteen European plant species, a statistical model for the estimation of the anaerobic biodegradability of plant material was developed. We show that this new approach represents an accurate and cost-effective method to identify valuable energy plants for sustainable energy production. In particular, anaerobic biodegradability (B-o) of lignocellulosic material was empirically found to be related to the amount of cellulose plus lignin, as analytically assessed by the van Soest method, i.e., the acid detergent fiber (ADF) value. Apart from being theoretically meaningful, the ADF-based empirical model requires the least effort compared to the other four proposed conceptual models proposed, as individual fractions of cellulose, hemicellulose, and lignin do not need to be assessed, which also enhances the predictive accuracy of the model's estimation. The model's results showed great predictability power, allowing us to identify interesting crops for sustainable crop rotations. Finally, the model was used to predictB(o)of 114 European plant samples that had been previously characterized by means of the van Soest method.
Address [Pabon-Pereira, Claudia P.] Univ Adolfo Ibanez, Fac Engn & Sci, Diagonal Las Torres 2700, Penalolen 2700, Santiago De Chi, Chile, Email: claudia.pabon@uai.cl;
Corporate Author Thesis
Publisher Mdpi Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2227-9717 ISBN Medium
Area Expedition Conference
Notes WOS:000556716400001 Approved
Call Number UAI @ eduardo.moreno @ Serial 1217
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Author (up) Pedrouso, A.; Vazquez-Padin, J.R.; Crutchik, D.; Campos, J.L.
Title Application of Anammox-Based Processes in Urban WWTPs: Are We on the Right Track? Type
Year 2021 Publication Processes Abbreviated Journal Processes
Volume 9 Issue 8 Pages 1334
Keywords autotrophic nitrogen removal; effluent quality; energy efficiency; mainstream; nitritation; sludge thermal hydrolysis
Abstract The application of partial nitritation and anammox processes (PN/A) to remove nitrogen can improve the energy efficiency of wastewater treatment plants (WWTPs) as well as diminish their operational costs. However, there are still several limitations that are preventing the widespread application of PN/A processes in urban WWTPs such as: (a) the loss of performance stability of the PN/A units operated at the sludge line, when the sludge is thermally pretreated to increase biogas production; (b) the proliferation of nitrite-oxidizing bacteria (NOB) in the mainstream; and (c) the maintenance of a suitable effluent quality in the mainstream. In this work, different operational strategies to overcome these limitations were modelled and analyzed. In WWTPs whose sludge is thermically hydrolyzed, the implementation of an anerobic treatment before the PN/A unit is the best alternative, from an economic point of view, to maintain the stable performance of this unit. In order to apply the PN/A process in the mainstream, the growth of ammonia-oxidizing bacteria (AOB) should be promoted in the sludge line by supplying extra sludge to the anaerobic digesters. The AOB generated would be applied to the water line to partially oxidize ammonia, and the anammox process would then be carried out. Excess nitrate generated by anammox bacteria and/or NOB can be removed by recycling a fraction of the WWTP effluent to the biological reactor to promote its denitrification.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2227-9717 ISBN Medium
Area Expedition Conference
Notes WOS:000690228200001 Approved
Call Number UAI @ alexi.delcanto @ Serial 1453
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Author (up) Toledo, P.A.; Riquelme, S.R.; Campos, J.A.
Title Earthquake source parameters that display the first digit phenomenon Type
Year 2015 Publication Nonlinear Processes In Geophysics Abbreviated Journal Nonlinear Process Geophys.
Volume 22 Issue 5 Pages 625-632
Keywords
Abstract We study the main parameters of earthquakes from the perspective of the first digit phenomenon: the nonuniform probability of the lower first digit different from O compared to the higher ones. We found that source parameters like coseismic slip distributions at the fault and coseismic inland displacements show first digit anomaly. We also found the tsunami runups measured after the earthquake to display the phenomenon. Other parameters found to obey first digit anomaly are related to the aftershocks: we show that seismic moment liberation and seismic waiting times also display an anomaly. We explain this finding by invoking a selforganized criticality framework. We demonstrate that critically organized automata show the first digit signature and we interpret this as a possible explanation of the behavior of the studied parameters of the Tohoku earthquake.
Address [Toledo, P. A.] Univ Adolfo Ibanez, Fac Engn & Sci, Santiago, Chile, Email: patricio.toledo@uai.cl
Corporate Author Thesis
Publisher Copernicus Gesellschaft Mbh Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1023-5809 ISBN Medium
Area Expedition Conference
Notes WOS:000364328900010 Approved
Call Number UAI @ eduardo.moreno @ Serial 539
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Author (up) Urbina, C.A.F.; Alanís, D.C.; Ramírez, E.; Seguel, O.; Fustos, I.J.; Donoso, P.D.; de Miranda, J.H.; Rakonjac, N.; Palma, S.E.; Galleguillos, M.
Title Estimating soil water content in a thorny forest ecosystem by time-lapse electrical resistivity tomography (ERT) and HYDRUS 2D/3D simulations Type
Year 2023 Publication Hydrological Processes Abbreviated Journal Hydrol. Process.
Volume 37 Issue 10 Pages e15002
Keywords applied geophysics; HYDRUS 1D; Vachellia caven; water balance; water transfer models
Abstract Determination of soil volumetric water content theta in forest ecosystems is particularly challenging due to deep rooting systems and unknown soil vertical and spatial heterogeneity. This research aims to test two undisturbed methods, electrical resistivity tomography (ERT) and HYDRUS 2D/3D, for 2D theta determination in a thorny forest ecosystem. The experiment consisted of infiltrating 10 L of water lasting 60 min. During infiltration, ERT measured apparent resistivity by time-lapse measurements, and theta was measured with an FDR probe (EnviroSCAN) at 33, 63, 83, 97, and 163 cm depth close to the infiltration site. At the end of infiltration, a soil pit was dug, and 100 measurements of theta were performed with a TDR in a 10 x 10 cm regular grid. Archie law transformed soil resistivity (ERT) into theta using manual calibration, verified by an independent dataset. The 2D theta profile obtained by ERT was qualitatively compared with the HYDRUS 2D/3D one. HYDRUS 2D/3D was parametrized with calibrated parameters obtained with HYDRUS 1D using 106 days of theta obtained with EnviroSCAN. The results of HYDRUS 1D calibration and verification were satisfactory, with RMSE and Nash-Sutcliffe coefficients ranging from 0.021 to 0.034 cm(3 )cm(-3) and 0.11 to 0.77, respectively. The forward HYDRUS 2D/3D theta simulation disagrees with EnviroSCAN data for 33 cm depth. However, it follows the trend with near to zero variation of water content at 63 cm depth. Water content determination by ERT was satisfactory with RMSE for calibration and verification of 0.017 and 0.021 cm(3) cm(-3). HYDRUS 2D/3D and ERT comparisons were not equal, with a shallower wetting front by ERT and a deeper one for HYDRUS. Still, both wetting fronts agree with the wetting depth estimated by EnviroSCAN. We conclude that both methods are an alternative for theta determination in heterogeneous and deep soils of forest ecosystems.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0885-6087 ISBN Medium
Area Expedition Conference
Notes WOS:001082448200001 Approved
Call Number UAI @ alexi.delcanto @ Serial 1897
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