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Evolution of forest cover in Portugal: A review of the 12th–20th centuries

journal of Forestry Research 2014年第2期25卷 249-256页

作者： Fernando Reboredo joo pais Universidade Nova de Lisboa Faculdade de Ciências e TecnologiaCICEGeDepartmento de Ciências da Terra

Portugal＇s forests in the 12th century were dominated by the Fagaceae represented by Quercus and Castanea, and several pine species From the 12th century onwards, forests underwent changes in their management starting with protection and ultimately leading to intense exploitation. The massive naval construction during the maritime expansion （mainly in the 15th-16th centuries） involved felling of approximately 5 million trees mainly Quercus suber, Pinus pinea and other Quercus species. Cumulative fuel-wood consumption of 959 Mm3 during 1300-1854 was attributed to demographic expansion while the deforestation rate during 1636-1854 accounted for a minimum of 72.6% and a maximum of 96% of total forest cover. The volume of timber used in railway sleepers from 1856 onwards might have reached 0.5 Mm3. The last quarter of the 20th century increased the forest cover of Portugal through the World Bank program of Eucalyptus globulus reforestation.

关键词： forest cover change forest exploitation forest economics Portugal.

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The role of surface functionalization of silica nanoparticles for bioimaging

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journal of Innovative optical Health Sciences 2016年第4期9卷 11-26页

作者： Maria C.Gomes Angela Cunha Tito Trindade joão P.C.Tome QoPNA University of Aveiro 3810-193 AveiroPortugal CICECo and Department of Chemistry University of Aveiro 3810-193 AveiroPortugal CESAM and Department of Biology University of Aveiro 3810-193 AveiroPortugal Centro de Quimica Estrutural Instituto Superior Tecnico Universidade de LisboaAv.Rovisco Pais1049-001 LisboaPortugal Department of organic and Macromolecular Chemistry Ghent University B-9000 Gent Belgium

Among the several types of inorganic nanoparticles available,silica nanoparticles(SNP)have earned their relevance in biological applications namely,as bioimaging *** fact,uorescent SNP(FSNP)have been explored in this-eld as protective nanocarriers,overcoming some limitations presented by conventional organic dyes such as high photobleaching rates.A crucial aspect on the use of uorescent SNP relates to their surface properties,since it determines the extent of interaction between nanoparticles and biological systems,namely in terms of colloidal stability in water,cellular recognition and internalization,tracking,biodistribution and speci-city,among ***,it is imperative to understand the mechanisms underlying the interaction between biosystems and the SNP surfaces,making surface functionalization a relevant step in order to take full advantage of particle *** versatility of the surface chemistry on silica platforms,together with the intrinsic hydrophilicity and biocompatibility,make these systems suitable for bioimaging applications,such as those mentioned in this review.

关键词： Fluorescent silica nanoparticles bioimaging surface functionalization nanoparticlecell interactions.

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optimization of high-speed railway pantographs for improving pantograph-catenary contact

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Theoretical & Applied Mechanics Letters 2013年第1期3卷 51-57页

作者： jorge Ambrósio joo Pombo Manuel Pereira IDMEC-IST Technical Univ. of Lisbon Av. Rovisco pais

A crucial system for the operation of high-speed trains is the pantograph catenary interface as it is the sole responsible to deliver electrical power to the train. Being the catenary a stationary system with a long lifespan it is also less likely to be redesigned and upgraded than the pantographs that fit the train vehicles. This letter proposes an optimization procedure for the improvement of the contact quality between the pantograph and the catenary solely based on the redesign of the pantograph head suspension characteristics. A pantograph model is defined and validated against experimental dynamic characteristics of existing pantographs. An optimization strategy based on the use of a global optimization method, to find the vicinity of the optimal solution, followed by the use of a deterministic optimization algorithm, to fine tune the optimal solution, is applied here. The spring stiffness, damping characteristics and bow mass are the design variables used for the pantograph optimization. The objective of the optimal problem is the minimization of the standard deviation of the contact force history, which is the most important quantity to define the contact quality. The pantograph head suspension characteristics are allowed to vary within technological realistic limits. It is found that current high-speed railway pantographs have a limited potential for mechanical improvements, not exceeding 10% 15% on the decrease of the standard deviation of the contact force. C 2013 The Chinese Society of Theoretical and Applied Mechanics. [doi：10.1063/2.1301306]

关键词： high-speed railway pantograph

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Design and Control Nonlinear Dynamic Response optimization of Flexible Mechanical Systems

Design and Control Nonlinear Dynamic Response Optimization o...

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The Fourth World Congress of Structural and Multidisciplinary optimization

作者： Paulo Pires Moita jorge Pinto Pereira jo o Barradas Cardoso Escola Superior de Tecnologia de Setúbal Campus do IPS 2914-508 SetúbalPortugal Escola Superior de Tecnologia de Setúbal Campus do IPS 2914-508 SetúbalPortugal Instituto Superior Técnico Departamento de Engenharia Mec（a|＾）nica Av. Rovisco Pais1049-001 LisboaPortugal

＜正＞A design and control sensitivity analysis and multicriteria optimization formulation is derived for flexible mechanical systems. This formulation is implemented in an optimum design code and it is applied to the nonlinear response of an impact absorber and to a flexible vehicle chassis with suspension. Structural dimensions as well as lumped damping and stiffness characteristics plus control driven forces, are considered as decision variables. The dynamic response and its sensitivity are discretized via space and time finite elements, and are integrated globally or step-by-step. Direct differentiation and adjoint system approaches are used to calculate the sensitivities. Nonlinear programming and optimality criteria are used for the optimization process.

关键词： optimization Nonlinear Structures Dynamic Response Space-Time Finite Elements

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Trefftz Spectral Analysis of Biphasic Media

Trefftz Spectral Analysis of Biphasic Media

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The Sixth World Congress on Computational Mechanics in Conjunction with the Second Asian-Pacific Congress on Computational Mechanics

作者： joo A.Teixeira de Freitas Ionut D.Moldovan Milan Toma Departamento de Engenharia Civil e Arquitectura Instituto Superior Técnico Universidade Técnica de Lisboa Av. Rovisco pais 1049-001 Lisboa Portugal

The hybrid-Trefftz finite element formulation is used to model the response of two-phase media in the frequency domain. The applications selected illustrate the relative advantage of Trefftz elements over conventional elements in the modeling of wave propagation in unbounded saturated porous media and of the transient response of incompressible soft tissues.

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波尔图Fraunhofer新总部

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设计家 2012年第2期 90-95页

作者： Hugo Ramos Rita pais Jette Fyhn Dina Castro Andr Gois Fernandes Ricardo Sousa. Bruno Almeida Rita a joana Coimbra JCT with GATFNGRL Astratec with Prolicht Lighting BENE Empatias joo Morgado Pauline Pan Pedra Silva Architects

设计师应邀来设计位于波尔图技术大学校园内的新总部。他们通过传达一个简单而积极的动态信息，将弗劳恩霍夫的创新哲学纳入了设计考量的范畴。弗劳恩霍夫办公创新中心位于斯图加特．其创新工作室布局及组织元素为弗劳恩霍夫的设计理念... 详细信息

设计师应邀来设计位于波尔图技术大学校园内的新总部。他们通过传达一个简单而积极的动态信息，将弗劳恩霍夫的创新哲学纳入了设计考量的范畴。弗劳恩霍夫办公创新中心位于斯图加特．其创新工作室布局及组织元素为弗劳恩霍夫的设计理念增添了一个新的层次。

关键词：波尔设计师大学校园动态信息设计理念斯图加特创新工作室

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空间、环境和历史因素对热带森林树种周转的影响

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journal of Plant Ecology 2021年第4期14卷 717-729页

作者： Alisson Borges Miranda Santos Vinicius Andrade Maia Cleber Rodrigo de Souza Nathalle Cristine Alencar Fagundes Fernanda Moreira Gianasi Aurelio de Jesus Rodrigues pais Natalia de Aguiar-Campos Gabriela Gomes Pires Diego Teixeira Girardelli Jean Daniel Morel Mariana Caroline Moreira Morelli Felipe de Carvalho Araujo Rubens Manoel dos Santos Department of Forestry Sciences Federal University of LavrasUniversity CampusLavrasBrazil Biological Sciences University of the State of Minas GeraisItuiutaba UnitItuiutabaBrazil Department of Biology Federal University of LavrasUniversity CampusLavrasBrazil Faculty of Environmental Engineering and Natural Resources Zambeze UniversityChimoioMozambique

本文通过回答以下问题来分析空间距离、当前和过去的环境差异及这几个因素对树木群落分类和系统发育转换的影响:(i)树木群落分类和系统发育转换是否与空间距离通过环境差异产生的间接影响相关?(ii)树木群落分类和系统发育转换是否随古气... 详细信息

本文通过回答以下问题来分析空间距离、当前和过去的环境差异及这几个因素对树木群落分类和系统发育转换的影响:(i)树木群落分类和系统发育转换是否与空间距离通过环境差异产生的间接影响相关?(ii)树木群落分类和系统发育转换是否随古气候(末次盛冰期和中全新世)的变化而变化?本文对巴西的14个大西洋雨林样点(采样面积20.4 ha)83个科615个种进行了研究,获得了当前、中全新世和末次盛冰期的地块地理坐标、土壤变量和样点生物气候变量。我们使用基于距离的结构方程模型(SEM)来(i)检测空间距离和环境差异的直接影响,以及(ii)检测空间距离通过环境差异对分类(Bray-Curtis距离)和系统发育转换(Comdist和Comdistnt距离)的间接影响。研究结果表明,空间距离通过环境差异对分类和系统发育转换的间接影响较弱。基于生态位中性的历史过程带来的直接影响驱动了树木群落的转换。因此,我们推断古气候(历史过程)促进了产生当前植物区系分支的选择,而空间距离(中性的过程)限制了物种从区域种库向外扩散的范围,环境条件(基于生态位的过程)则在本地选择能够持续生存的分类群。

关键词：聚类过程系统发育群落环境过滤中性群落系统发育转换生态位古气候效应

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