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Inundation Maps for Extreme Flood Events at the Mouth of the Danube River

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International Journal of Geosciences 2011年第1期2卷 68-74页

作者： Daniela E.Nistoran Gogoase iuliana armas Cristina S.Ionescu Hydraulics Department University“Politehnica”of BucharestBucharestRomania Department of Geography University of BucharestBucharestRomania

Hydrodynamic modeling is used to analyse the inundation behavior of St. George village during extreme flood events, in particular for a flood happened in spring 2006. The study reach, 4 km in length, is situated in the Danube Delta, at the mouth of St. George distributary and includes St. George village. Land and bathymetric surveys were used to create a digital terrain model (DTM) of the river channel and the village. By coupling the geometry with hydrologic data, a 2D hydrodynamic model was built up with the help of the CCHE2D code (University of Mississippi). The model is based on integrating Saint-Venant shallow waters (depth averaged) equations through finite-difference implicit numerical scheme. It was calibrated in terms of roughness coefficients on measured values of water surface elevation registered in the St. George port. Flood maps obtained from computations were compared to satellite images from the same days of the spring 2006 extreme event. Inundation behaviour of the St. George village was analysed for different scenarios of river hydrological and sea level (variable because of wind waves) conditions. Findings were compared with high water marks and inhabitants testimonials. The model proved that sea level has a higher influence upon the inundability of the area than the river flood events.

关键词： Hydraulic Modeling Finite Difference Method Flood Inundation Maps

Generation of lossy mode resonances(LMR)using perovskite nanofilms

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Opto-Electronic Advances 2024年第2期7卷 33-40页

作者： Dayron armas Ignacio R.Matias M.Carmen Lopez-Gonzalez Carlos Ruiz Zamarreño Pablo Zubiate Ignacio del Villar Beatriz Romero Electrical Electronic and Communications Engineering DepartmentPublic University of NavarraPamplona 31006Spain Institute of Smart Cities(ISC) Public University of NavarraPamplona 31006Spain Experimental Science and Technology School Rey Juan Carlos UniversityMostoles 28933Spain

The results presented here show for the first time the experimental demonstration of the fabrication of lossy mode resonance(LMR) devices based on perovskite coatings deposited on planar waveguides. Perovskite thin films have been obtained by means of the spin coating technique and their presence was confirmed by ellipsometry, scanning electron microscopy, and X-ray diffraction testing. The LMRs can be generated in a wide wavelength range and the experimental results agree with the theoretical simulations. Overall, this study highlights the potential of perovskite thin films for the development of novel LMR-based devices that can be used for environmental monitoring, industrial sensing, and gas detection, among other applications.

关键词： perovskite thin films slab waveguide lossy mode resonance

Morphological and molecular diversity of arbuscular mycorrhizal fungi in revegetated iron-mining site has the same magnitude of adjacent pristine ecosystems

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Journal of Environmental Sciences 2018年第5期30卷 330-343页

作者： Caroline Krug Vieira Matheus Nicoletti Marascalchi Arthur Vinicius Rodrigues Rafael Dutra de armas Sidney Luiz Stürmer Universidade Regional de Blumenau(FURB) Programa de Pos-Graduacao em Engenharia Ambiental89030-903 BlumenauSCBrazil Universidade Regional de Blumenau(FURB) Departamento de Ciencias Naturais(DCN)89030-903 BlumenauSCBrazil Uniuersidade Regional de Blumenau(FURB) Programaa de Pos-Graduacao em Engenharia Florestal89030-903 BlumenauSCBrazil Centro Universitario-Catolica de Santa Catarina 89203-005 JoinvilleSCBrazil

Arbuscular mycorrhizal fungi（AMF） are important during revegetation of mining sites, but few studies compared AMF community in revegetated sites with pristine adjacent ecosystems. The aim of this study was to assess AMF species richness in a revegetated iron-mining site and adjacent ecosystems and to relate AMF occurrence to soil chemical parameters. Soil samples were collected in dry and rainy seasons in a revegetated iron-mining site（RA） and compared with pristine ecosystems of forest（FL）, canga（NG）,and Cerrado（CE）. AMF species were identified by spore morphology from field and trap cultures and by LSU r DNA sequencing using Illumina. A total of 62 AMF species were recovered, pertaining to 18 genera and nine families of Glomeromycota. The largest number of species and families were detected in RA, and Acaulospora mellea and Glomus sp1 were the most frequent species. Species belonging to Glomeraceae and Acaulosporaceae accounted for 42%–48% of total species richness. Total number of spores and mycorrhizal inoculum potential tended to be higher in the dry than in the rainy season, except in RA. Sequences of uncultured Glomerales were dominant in all sites and seasons and five species were detected exclusively by DNA-based identification. Redundancy analysis evidenced soil p H,organic matter, aluminum, and iron as main factors influencing AMF presence. In conclusion, revegetation of the iron-mining site seems to be effective in maintaining a diverse AMF community and different approaches are complementary to reveal AMF species, despite the larger number of species being identified by traditional identification of field spores.

关键词： Community structure Glomeromycota Illumina LSU rDNA Spore morphology Taxonomic distinctness index

Resource economics and coordination among above- and below-ground functional traits of three dominant shrubs from the Chilean coastal desert

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Journal of Plant Ecology 2015年第1期8卷 70-78页

作者： Joaquín Morales Francisco A.Squeo Yann Tracol Cristina armas Julio R.Gutiérrez Facultad de Ciencias Universidad de La SerenaCasilla 554La SerenaChile Institute of Ecology and Biodiversity(IEB) Casilla 653SantiagoChile Center of Advanced Studies in Arid Zones Casilla 554La SerenaChile

Aims Plant functional traits determine how plants respond to environmen-tal factors and influence ecosystem *** them,root traits and analyses of relations between above and below-ground traits in natural communities are *** we characterized a set of above-and below-ground traits of three dominant shrub species in a semiarid shrub-steppe that had contrasting leaf pheno-logical habits(deciduous,semideciduous and evergreen).We ana-lysed if there was coordination among above-and below-ground resource economics patterns:*** of biomass allocation,construction costs and *** Findings Above-and below-ground traits and their resource economics relations pointed to species-specific functional strategies to cope with drought and poor soils and to a species ranking of fast to slow whole-plant strategies in terms of resource uptake,biomass con-struction costs and *** deciduous shrub,Proustia cunei-folia,had relatively deep and even distribution of roots,and high proportion of short-lived tissues of low C construction costs:it had high fine to coarse root and high leaf-to-stem biomass ratios,high specific leaf area(SLA),and stems of low wood *** strat-egy allows Proustia to maximize and coordinate above-and below-ground resources uptake as long as the most limiting factor(water)is available,but at the cost of having relative high plant biomass *** evergreen Porlieria chilensis,instead,displayed a more conservative and slow strategy in terms of resource *** had~80%of the roots in the 40 cm topsoil profile,low pro-portion of fine compared with coarse roots and low leaf-to-stem ratios,low SLA and stems of high wood density,*** invested in C costly tissues that,overall,persist longer but probably at the cost of having lower plant resource uptake *** in the semide-ciduous Adesmia bedwellii were in between these two functional *** results revealed high functional diversity and above-

关键词： drought functional diversity mass fractions root distribution specific leaf area

Functional groups of Sahelian trees in a semiarid agroforestry system of Senegal

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Journal of Plant Ecology 2018年第3期11卷 375-384页

作者： Joseph S.Diémé Mayécor Diouf Cristina armas Graciela MRusch Francisco I.Pugnaire Estación Experimental de ZonasÁridas Consejo Superior de Investigaciones CientíficasCtra.de Sacramento s/n04120 La CañadaAlmeríaSpain Centre National de Recherches Forestières Institut Sénégalais de Recherches Agricoles(CNRF/ISRA)DakarSenegal Norwegian Institute for Nature Research TrondheimNorway

Aims Addressing plant responses to water stress is critical to understand the structure of plant communities in water-limited environments and to forecast their resilience to future changes in *** a semiarid agroforestry system in the Sahelian savannah of Leona(Senegal),we selected nine common tree species and explored their stress-resistance *** species represent a variety of life forms and are of high regional socio-economic *** hypothesized that different species would show different suites of traits to cope with water stress and expected to identify functional groups differing in strategies to withstand water *** Along a dry and a wet season,we monitored four traits reflecting above-and below-ground strategies of resource acquisition such as predawn leaf water potential(ψpd),specific leaf area(SLA),leaf thickness and leaf area index(LAI).We also measured two mor-phological traits:trunk diameter and tree *** andψpd were measured six times during the dry and rainy seasons,and the other traits were measured *** Findings We identified two functional classes subdivided into two func-tional groups of each *** first class included deciduous and semi-deciduous species that generally had large SLA,low leaf thickness and small-to-intermediate inter-seasonal varia-tions inψ*** second class included evergreen species of two functional groups that differ in SLA,leaf thickness and the mag-nitude of inter-seasonal variations ofψpd throughout the *** four functional groups identified in this study represent plant strategies differing in their response to changing environmental conditions.

关键词： Acacia tortilis Adansonia digitata Balanites aegyptiaca Celtis integrifolia Combretum glutinosum Faidherbia albida functional traits Neocarya macrophyla Sclerocarya birrea Tamarindus indica water stress

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Don Quijote

Inhibition of the growth and development of mosquito larvae of Culex quinquefasciatus(Diptera:Culicidae) treated with extract from leaves of Pseudocalymma alliaceum(Bignonaceae)

作者： Miguel de Cervantes translated by Burton Raffel edited by Diana de armas Wilson.

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Asian Pacific Journal of Tropical Medicine 2014年第8期7卷 594-601页

作者： Carlos Granados-Echegoyen Rafael Pérez-Pacheco Marcos Soto-Hernndez Jaime Ruiz-Vega Luicita Lagunez-Rivera Nancy Alonso-Hernandez Rene Gato-armas CIIDIR-OAXACA Instituto Poluécnico NacionalCalle Hornos 1003Santa CruzXoxocotlnOaxacaMéxico.C.P.71230 Colegio de Postgraduados MontecilloEstada de MéxicoMexico Institute de Medicina Tropical "Pedro Kouri" La HabanaCuba

Objective:To determine larvicidal activity of the essential oil,hydrolat and botanical extracts derived from leaves ol Pseudocalymma alliaceum an mosquito larvae of Culex ***:Groups of twenty lanae were used in the larvicidal *** mortality,relative growth rate,the larval and pupal duration and viability was *** essential oil was analyzed by solid phase microextraction using gas chromatography coupled to mass ***:Essential oil at 800 ppm showed larvicidal activity at 24 h with lethal values of LC_(50) and LC_(90) of 267.33 and 493.63 *** hvdrolat at 20% and 10% on 2nd stage larvae showed 100%effectiveness after 24 *** aqueous extract at 10% had a relative growth index of *** the ethanolic and methanolic extract obtained values of 0.76 and 0.70 and control reached *** treated with 10% of methanol,ethanol and aqueous extract showed a reduction in larval duration of 5.00,2.20 and 4.35 days;ethanol extract at 1% provoke decrease of 2.40 days in the development and exhibited an increment of 3.30 days when treated with 0.01%.Aqueous,ethanol and methanol extracts at 10%reduced in 6.15,3.42 and 5.57 days pupal *** main compounds were diallyl disulfide(50.05%),diallyl sulfide(11.77%) and disulfide di-2-propenyl(10.37%).Conclusions:The study demonstrated for the first time,the larvicidal activity of the essential oil and hydrolat of Pseudocalymma alliaceum:aqueous,ethanol and methanol extracts inhibited the normal growth and development of mosquito larvae,prolonging and delaying larval and pupal duration.

关键词： Pseudocallyma Mosquito control growth inhibition Botanical extracts Essential oils Hydrolat

Optimization of Micromechanical Cleavage Technique of Natural Graphite by Chemical Treatment

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Graphene 2014年第1期3卷 1-5页

作者： Luis Torres Luis Gomez armas Antonio Carlos Seabra Centro de Ciências Naturais e Humanas Universidade Federal do ABC Sao Paulo Brazil Grupo de óptica Micro e Nanofabricao de Dispositivos (GOMNDI) Universidade Federal do Pampa Rio Grande do Sul Brazil Laboratório de Sistemas Integráveis do Departamento de Engenharia de Sistemas Eletronicos da Escola Politécnica da USP (LSI-PSI/EPUSP) Sao Paulo Brazil

In this work,we report a method to improve the efficiency of the micromechanical cleavage technique to obtain few-layers graphene samples, from natural graphite flakes, which were previously submitted to two chemical treatment times with H2SO4(17 and 25 hours). After the chemical treatment times, Raman spectroscopy reveals a hydrogenation of the few-layer graphene samples, which were obtained from the treated graphite flakes. To analyze the hydrogenation of the samples, the G and 2D bands of the Raman spectra of the treated and un-treated samples were analyzed and compared, as well as the I(2D)/I(G) ratio, revealing a p-doping on the treated samples when compared with the untreated samples. Our studies could be of great importance to obtain larger and greater amount of few-layer graphene samples.

关键词： Graphene Micromechanical Cleavage Raman Spectroscopy Chemical Treatment

学习策略对YCT考试成绩的影响研究 ——以拉斯帕尔马斯大学孔子学院的中学生为个案

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学习策略对YCT考试成绩的影响研究 ——以拉斯帕尔马斯大学孔子学...

作者： AINHOA RAMóN armas（爱诺）大连外国语大学

学位级别：硕士

本文通过拉斯帕尔马斯大学孔子学院中学生学习汉语的案例,研究学习策略对汉语学习的影响。众所周知,学习策略在第二语言习得中占有重要的地位。研究采用问卷的形式,以著名的Oxford语言学习策略量表为基础,对拉斯帕尔马斯孔院中学生使用... 详细信息

本文通过拉斯帕尔马斯大学孔子学院中学生学习汉语的案例,研究学习策略对汉语学习的影响。众所周知,学习策略在第二语言习得中占有重要的地位。研究采用问卷的形式,以著名的Oxford语言学习策略量表为基础,对拉斯帕尔马斯孔院中学生使用的学习策略情况,以及他们的YCT考试成绩与他们的个人现状与学习策略使用的关系进行了调查。此次调查分析的目的是为了了解学习汉语的中学生最常用的学习策略,以及使用的学习策略对YCT考试成绩的影响,以便提升学生的汉语学习能力。同时,该研究也可以为教师提出一些教学建议,使教师们能够更好地在学生语言学习策略中发挥作用。全文分为五个部分,具体结构如下:第一部分为绪论。主要阐明了选题的目的与意义,介绍了研究对象与研究方法。第二部分是研究的理论依据。首先,该部分概述了学习策略的研究理论及其重要性。其次是第二语言学习策略的结构和本文所运用的Oxford语言学习策略研究及SILL量表介绍。接着介绍孔子学院在世界的发展情况,以及孔子学院在西班牙尤其是在拉斯帕尔马斯的发展情况,简要叙述全球汉语学习者的学习现状。最后,分析了以西班牙语为母语的汉语学习者学习的现状。第三部分为研究设计。阐述了研究假设、研究对象、研究工具以及研究的实施过程。第四部分是研究结果与参与调查的学生学习策略应用的现状分析。笔者在调查的基础上,对变量以及变量的相互关系进行了分析,同时,笔者也将研究结果跟相关研究进行了对比。第五部分是研究结论与建议。根据学习策略对学习成果的影响,对提升学生汉语学习能力提出了建议,同时也对教师的教学提出一些建议。研究结果分析表明,按照Oxford提出的方法,参与学生的语言学习策略的使用频率为“有时使用该策略”。结果证明,在参与调查的中学生中,使用最多的是补偿策略,次之是社会策略,接下来是使用频率几乎相同的记忆策略和认知策略,再者是元认知策略,使用人数最少的为情感策略。这些参与研究的学生的数据显示,没有“总是使用”的策略,没有“经常使用”的策略,也没有“从未使用”的策略。说明了从总体上讲,拉斯帕尔马斯孔子学院中学生在不同程度上使用了各种学习策略。关于性别情况,参与本研究的所有男女中学生的汉语学习策略频率平均值几乎相同。此外,通过变量的相互关系的分析,笔者得知本研究的变量与研究对象并没有十分显著的相互关系。值得一提的是,最初笔者研究设计中的变量并不包括不同学校的学生的差异分析,但是在分析数据的过程中,由于两所学校的变量参差不齐,笔者发现两所学校的学生的结果也存在着差异,因此又对差异结果进行了分析。最后,为了检验本研究结论的可靠性,笔者将自己的研究结果与相关的研究结果进行了对比分析,参考了其他的以母语为西班牙语的汉语学习策略的研究。

关键词：汉语学习策略 YCT考试成绩中学生案例研究