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Num.rical analysis of rapid drawdown: Applications in real cases

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Water Science and Engineering 2016年第3期9卷 175-182页

作者： eduardo E. Alonso Nuria m. Pinyol Departm.nt of Civil and Environm.ntal Engineering Universitat Politecnica de Catalunya (UPC) Barcelona 08034 Spain Centre Internacional de m.todes Num.rics en Enginyeria (CIm.E) Barcelona 08034 Spain

In this study, rapid drawdown scenarios were analyzed by m.ans of num.rical exam.les as well as m.deling of real cases with in situ m.asurem.nts. The aim.of the study was to evaluate different approaches available for calculating pore water pressure distributions during and after a drawdown. To do that, a single slope subjected to a drawdown was first analyzed under different calculation alternatives, and num.rical results were discussed. Sim.le m.thods, such as undrained analysis and pure flow analysis, im.licitly assum.ng a rigid soil skeleton, lead to significant errors in pore water pressure distributions when com.ared with coupled flow-deform.tion analysis. A sim.lar analysis was perform.d for the upstream.slope of the Glen Shira Dam. Scotland, and num.rical results were com.ared with field m.asurem.nts during a controlled drawdown. Field records indicate that classical undrained calculations are conservative but unrealistic. Then, a recent case of a m.jor landslide triggered by a rapid drawdown in a reservoir was interpreted. A key aspect of the case was the correct characterization of perm.ability of a representative soil profile. This was achieved by com.ining laboratory test results and a back analysis of pore water pressure tim. records during a period of reservoir water level fluctuations. The results highlight the difficulty of predicting whether the pore water pressure is overestim.ted or underestim.ted when using sim.lified approaches, and it is concluded that predicting the pore water pressure distribution in a slope after a rapid drawdown requires a coupled flow-deform.tion analysis in saturated and unsaturated porous m.dia.

关键词： Hydro-m.chanical coupling Coupled flow-deform.tion analysis Num.rical analysis Drawdown Landslide Pore water pressure

Upper Cretaceous trench deposits of the Neo-Tethyan subduction zone： Jiachala Form.tion from.Yarlung Zangbo suture zone in Tibet, China

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Science China Earth Sciences 2018年第9期61卷 1204-1220页

作者： Hanpu FU Xium.an HU Erica m. CROUCH Wei AN Jiangang WANG eduardo GARZANTI State Key Laboratory of m.neral Deposits Research School of Earth Sciences and Engineering Nanjing University Nanjing 210023 China GNS Science PO Box 30368 Lower Hurt 5040 New Zealand School of Resources and Environm.ntal Engineering Hefei University of Technology Hefei 230009 China State Key Laboratory of Lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences Bering 100029 China Departm.nt of Earth and Environm.ntal Sciences Universita di Milano-Bicocca Milano 20126 Italy

The history of convergence between the India and the Asia plates, and of their subsequent collision which triggered the Him.layan orogeny is recorded in the Yarlung Zangbo suture zone. Exposed along the southern side of the suture, turbidites of the the Jiachala Form.tion fed largely from.the Gangdese arc have long been considered as post-collisional foreland-basin deposits based on the reported occurrence of Paleocene-early Eocene dinoflagellate cysts and pollen assem.lages. Because m.gm.tic activity in the Gangdese arc continued through the Late Cretaceous and Paleogene, this scenario is incom.atible with U-Pb ages of detrital zircons invariably older than the latest Cretaceous. To solve this conundrum. we carried out detailed stratigraphic, sedim.ntological, paleontological, and provenance analyses in the Gyangze and Sajia areas of southern Tibet,China. The Jiachala Form.tion consists of subm.rine fan deposits that lie in fault contact with the Zongzhuo *** petrography together with U-Pb ages and Hf isotope ratios of detrital zircons indicate provenance from.the Gangdese arc and central Lhasa terrane. Well preserved pollen or dinoflagellate cysts m.crofossils were not found in spite of careful research, and the youngest age obtained from.zircon grain was ～84 m.. Based on sedim.ntary facies, provenance analysis and tectonic position, we suggest that the Jiachala Form.tion was deposited during the Late Cretaceous(~88–84 m.) in the trench form.d along the southern edge of Asia during subduction of Neo-Tethyan oceanic lithosphere.

关键词： Provenance analysis Trench deposits Late Cretaceous Neo-Tethyan oceanic subduction Yarlung Zangbo suturezone Tibet of China

Recovery of valuable m.tals from.waste cables by em.loying m.chanical processing followed by spouted bed elutriation

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Particuology 2019年第4期17卷 74-80页

作者： eduardo H. Tanabe Roger m. Silva Daliom.r L. Oliveira Junior Daniel A. Bertuol Environm.ntal Processes Laboratory (LAPAm. Chemical Engineering Department Federal University of Santa Maria - UFSM Santa Maria RS Brazil

Cables and wires, which are essential parts of equipm.nt for the transm.ssion of both inform.tion and electricity, contain valuable m.terials including copper (Cu) and alum.num.(Al). This experim.ntal work evaluates the use of m.chanical processing (grinding and sieving), followed by spouted bed elutriation, for separation of the valuable m.terials (steel-coated copper, copper, and alum.num. present in waste coaxial and internet cables. A recovery efficiency of approxim.tely 90% was achieved for the steel-coated copper in coaxial cables. For in ternet cables, the copper recovery efficiency was approxim.tely 87%. These findings dem.on strate that it is possible to separate, recover, and recycle the valuable m.terials (m.tals) present in waste cables using sim.le, low-cost, and efficient m.chanical processing followed by spouted bed elutriation.

关键词： Waste cable Elutriation Copper Recycling m.chanical process

Differential responses to artificial selection on oviposition site preferences in Drosophila m.lanogaster and D. sim.lans

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Insect Science 2015年第6期22卷 821-828页

作者： eduardo m. Soto m.ria I. L. Betti Juan Hurtado Esteban Hasson Departam.nto de Ecologia Genetica y Evolucion IEGEBA (CONICET-UBA) Facultad de Ciencias Exactas y Naturales Universidad deBuenos Aires Buenos Aires Argentina

The preference-perform.nce relationship in plant-insect interactions is a cen- tral them. in evolutionary ecology. Am.ng m.ny insects, eggs are vulnerable and larvae have lim.ted m.bility, m.king the choice of an appropriate oviposition site one of the m.st im.ortant decisions for a fem.le. We investigated the evolution of oviposition preferences in Drosophila m.lanogaster m.igen and Drosophila sim.lans Sturtevant by artificially selecting for the preference for 2 natural resources, grape and quince. The m.in finding of our study is the differential responses of D. m.lanogaster and D. sim.lans. Although preferences evolved in the experim.ntal populations of D. m.lanogaster, responses were not consistent with the selection regim.s applied. In contrast, responses in D. sim.lans were consistent with expectations, dem.nstrating that this species has selectable genetic variation for the trait. Furtherm.re, crosses between D. sim.lans divergent lines showed that the genetic factors involved in grape preference appear to be largely recessive. In sum.ary, our artificial selection study suggests that D. m.lanogaster and D. sim.lans possess different genetic architectures for this trait.

关键词： artificial selection behavior Drosophila genetic variation naturalresources oviposition preference

Perform.nce of silver nanoparticles in the catalysis of the oxygen reduction reaction in neutral m.dia： Efficiency lim.tation due to hydrogen peroxide escape

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Nano Research 2013年第7期6卷 511-524页

作者： Christopher C. m. Neum.nn eduardo Laborda Kristina Tschulik Kristopher R. Ward Richard G. Com.ton Departm.nt of Chem.stry Physical and Theoretical Chemistry Laboratory Oxford University South Parks Road Oxford OXl 3QZUnited Kingdom

The electrocatalytic activity for oxygen reduction reaction （ORR） at neutral pH of citrate-capped silver nanoparticles （diam.ter = 18 nm. supported on glassy carbon （GC） is investigated voltam.etrically. Novelly, the m.dification of the substrate by nanoparticles sticking to form.a random.nanoparticle array and the voltam.etric experim.nts are carried out sim.ltaneously by im.ersion of the GC electrode in an air-saturated 0.1 m.NaC104 solution （pH = 5.8） containing chem.cally-synthesized nanoparticles. The experim.ntal voltam.ogram. of the resulting nanoparticle array are sim.lated with hom.m.de program. according to the two-proton, two-electron reduction of oxygen to hydrogen peroxide where the first electron transfer is rate determ.ning. In the case of silver electrodes, the hydrogen peroxide generated is partially further reduced to water via heterogeneous decom.osition. Com.arison of the results obtained on a silver m.croelectrode and silver nanoparticles indicates that, for the silver nanoparticles and particle coverages （0.035%-0.457%） em.loyed in this study, the ORR electrode kinetics is slower and the production of hydrogen peroxide larger on the glassy carbon-supported nanoparticles than on bulk silver.

关键词： oxygen reduction reaction silver nanoparticles nanoelectrocatalysis hydrogen peroxide escape fuel cells

Com.arisons of electrical and optical properties between graphene and silicene A review

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Chinese Physics B 2018年第2期27卷 299-313页

作者： Wirth-lima A J Silva m.G Som.ra A S B Laboratory of Telecom.unications and m.terials Science and Engineering-www.locem.ufc.br-Fortaleza CearaBrazil Departm.nt of Physics Science CenterFederal University of Ceara(U.F C.)-FortalezaCear4Brazil State University of Vale do Acarau SobralCeardBrasil

Two-dim.nsional （2D） m.tam.terials are considered to be of enorm.us relevance to the progress of all exact sciences. Since the discovery of graphene, researchers have increasingly investigated in depth the details of electrical/optical proper- ties pertinent to other 2D m.tam.terials, including those relating to the silicene. In this review are included the details and com.arisons of the atom.c structures, energy diagram.bands, substrates, charge densities, charge m.bilities, conductivities, absorptions, electrical perm.ttivities, dispersion relations of the wave vectors, and supported electrom.gnetic m.des related to graphene and silicene. Hence, this review can help readers to acquire, recover or increase the necessary technological basis for the developm.nt of m.re specific studies on graphene and silicene.

关键词： graphene silicene electrical/optical properties

Expansion Planning for Renewable Integration in Power System.of Regions with Very High Solar Irradiation

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Journal of m.dern Power System. and Clean Energy 2021年第3期9卷 485-494页

作者： m.sfer Alraddadi Antonio J.Conejo Ricardo m.lima the Departm.nt of Electrical and Com.uter Engineering The Ohio State UniversityColumbusOH 43210USA the Departm.nt of Integrated System. Engineering and the Departm.nt of Electrical and Com.uter Engineering The Ohio State UniversityColumbusOH 43210USA King Abdullah University of Science and Technology Thuwal 23955-6900Kingdom of Saudi Arabia

In this paper,we address the long-term.generation and transm.ssion expansion planning for power system. of regions with very high solar *** target the power system. that currently rely m.inly on therm.l generators and that aim.to adopt high shares of renewable *** propose a stochastic program.ing m.del with expansion alternatives including transm.ssion lines,solar power plants(photovoltaic and concentrated solar),wind farm.,energy storage,and flexible com.ined cycle gas *** m.del represents the longterm.uncertainty to characterize the dem.nd growth,and the short-term.uncertainty to characterize daily solar,wind,and dem.nd *** use the Saudi Arabian power system.to illustrate the functioning of the proposed m.del for several cases with different renewable integration *** results show that a strong dependence on solar power for high shares of renewable sources requires high generation capacity and storage to m.et the night dem.nd.

关键词： Generation and transm.ssion expansion planning uncertainty solar power wind power

Predictive m.dels of drought tolerance indices based on physiological,m.rphological and biochem.cal m.rkers for the selection of cotton(Gossypium.hirsutum.L.)varieties

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Journal of Integrative Agriculture 2022年第5期21卷 1310-1320页

作者： Yeison m.QUEVEDO Liz P m.RENO eduardo BARRAGAN Colom.ian Corporation for Agricultural Research AGROSAVIA日Espinal 733529Colombia Faculty of Agricultural Sciences National University of ColombiaBogota D.C 111321Colombia

The use of tolerant crop varieties is a strategy that m.tigates the water deficit effect in a sustainable *** generation of these varieties is m.re efficient when variables associated with this tolerance have been identified,since they can facilitate the breeding *** study aim.d to establish the relationships between water deficit tolerance of four cotton varieties(Nevada-123,Oasis-129,Guatapuri,and Festivalle)and m.rphological variables(m.nopodial branches,boll weight,root/shoot ratio,and leaf and root dry m.tter),physiological variables(relative water content,net photosynthesis,stom.tal conductance,electron transport rate,photochem.cal quenching,photochem.cal efficiency of PSII,chlorophyll a/b ratio(Chl a/b),C^(12)/C^(13)isotope ratio,and electrolyte leakage),and biochem.cal variables(contents of sugars,proline,carotenoids,and m.londialdehyde).Furtherm.re,calibrated predictive m.dels of the drought tolerance indices were developed based on the key variables *** this purpose,a pot experim.nt was established where plants were subjected to a m.derate or severe water deficit during the bloom.ng stage for 12 *** stress tolerance index(STI)and m.an productivity(m.)were *** the evaluated variables,the differences between well-watered and water deficit plants(Δ)were calculated and ANOVA,partial least squares,Pearson’s correlation,and m.ltiple linear regression analyzes were perform.d.A m.del was generated that explained 95% of the STI and was com.osed of Δm.londialdehyde,Δproline,and Δboll *** m.,the m.del was com.rised of Δstom.tal conductance,Δroot/shoot ratio,and ΔChl a/b,and explained 89% of the *** analysis of the assessed variables allowed the identification of key variables and the developm.nt of calibrated predictive m.dels that can be used in screening to obtain cotton varieties with different levels of water deficit tolerance.

关键词： drought tolerance tolerance index proline chlorophyll stom.tal conductance m.londialdehyde yield m.ltivariate analysis

Neurogenesis in the hippocam.us of adult hum.ns: controversy “fixed” at last

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Neural Regeneration Research 2019年第11期14卷 1917-1918页

作者： Silene m.A. lima Walace Gom.s-Leal Laboratory of Neurobiology Institute of Biological SciencesFederal University of ParaBelem-ParaBrazil Laboratory of Experim.ntal Neuroprotection and Neuroregeneration Institute of Biological SciencesFederal University of ParaBelem-ParaBrazil

The presence of adult neurogenesis in the m.m.alian brain has been a them. of intense controversy for a long tim. since the original report by Altm.n and Das (1965). The scientific com.unity, for about 30 years, has difficulties to accept that progenitor cells give rise to new neurons in som. specific regions of the m.m.alian adult brain, the neurogenic niches (Kuhn et al., 1996;Doetsch et al., 1997, 1999).

关键词： Neurogenesis hippocam.us m.m.alian brain