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Open Source GIS Software Options for Forestry Education in Papua New Guinea

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Open Journal of Ecology 2014年第4期4卷 234-243页

作者： david lopez Cornelio Department of Forestry PNG University of Technology PMB Lae Papua New Guinea

Although open source softwares (OSS) for GIS and Remote Sensing are rapidly expanding and improving in the global context, there has been uncertainty at higher education institutions in developing countries, such as the department of forestry (Dfo) at Unitech, Papua New Guinea (PNG), regarding appropriate GIS softwares and hardware to acquire and use for teaching and research purposes. The paper briefly describes the characteristics of some mature OSS and discusses their main capabilities, advantages and disadvantages. Their adoption in the Dfo curricula may be advantageous in the long term, considering issues of learning curve steepness, versatility, affordability, effectiveness, and documentation available on them.

关键词： Open Source Software GIS Software Forestry Education

Highly accessible aqueous synthesis of well-dispersed dendrimer type platinum nanoparticles and their catalytic applications

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Nano Research 2019年第5期12卷 1083-1092页

作者： Adrian Fernandez-Lodeiro Jamila Djafari david lopez-Tejedor Carlos Perez-Rizquez Benito Rodriguez-Gonzalez Jose Luis Capelo Jose M.Palomo Carlos Lodeiro Javier Fernandez-Lodeiro BIOSCOPE Group LAQV@REQUIMTEChemistry DepartmentFaculty of Science and TechnologyUniversity NOVA of LisbonCaparica CampusCaparica 2829-516Portugal PROTEOMASS Scientific Society Rua dos InventoresMadan ParqueCaparica CampusCaparica 2829-516Portugal Department of Biocatalysis Institute of Catalysis(CSIC)MadridSpainMarie Curie 2CantoblancoUAM CampusMadrid 28049Spain Scientific and Technological Research Assistance Center(CACTI) University of VigoLagoas-MarcosendeVigo 36310Spain

The application of novel methodologies to the synthesis of nanomaterials is still a challenge in many different technological and scientific *** efficient and reproducible synthetic methodologies,that produce fewer residues and reduce the cost of raw materials must be *** the present work,we have explored the attractive possibility to apply the cheap iron (Ⅱ) sulphate salt in the reduction process of the K2PtCl4 to produce colloids *** synthesis took places in water and was assisted by sodium citrate (SC) using polyvinylpyrrolidone (PVP) as a *** adjustment of this novelty process allows obtaining well-dispersed and sub-20 nm dendrimer-type platinum nanoparticles (Pt D-NPs).The nano-dendrimers produced have been characterized using dynamic light scattering (DLS),transmission electron microscopy (TEM),high-resolution TEM (HR-TEM),XRD spectroscopy,inductive couple plasma (ICP) analysis,Fourier transform infrared (FT-IR) and ultraviolet-visible (UV-vis) *** conformational results derived from the size and shape will be *** application of the Pt D-NPs has been explored in the reduction of p-nitrophenol (p-NP) to p-aminophenol (p-AP) in aqueous media at room temperature obtained TOF value of 253 min^-***,our Pt D-NPs were tested as artificial metalloenzyme showing catechol oxidase activity for oxidation of L-DOPA.

关键词： platinum dendrimer NPs catalytic application green synthesis cateohol oxidase-like activity

Integration of Power MOSFETs for Synchronous Buck Converters

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Journal of Energy and Power Engineering 2012年第7期6卷 1126-1130页

作者： Juan A. Herbsommer Jonathan Noquil Osvaldo lopez david Jauregui Power Stage Business Unit Texas Instruments Bethlehem 18015 PA USA

Efficiency and power loss in the microelectronic devices is a major issue in power electronics applications. The engineers are challenged every year to increase power density and at the same time reduce the amount of power dissipated in the applications to keep the maximum temperatures under specifications. This situation drives a constant demand for better efficiencies in smaller packages. Traditional approaches to improve efficiency in DC/DC synchronous buck converters include reducing conduction losses in the MOSFETs （metal oxide semiconductor field effect transistors） through lower RDS （ON）（resistance drain to source in the ON state） devices and lowering switching losses through low-frequency operation. However, the incremental improvements in RDS （ON） are at a point of diminishing returns and low RDS （ON） devices have large parasitic capacitances that do not facilitate the high-frequency operation required to improve power density. The drive for higher efficiency and increased power in smaller packages is being addressed by advancements in both silicon and packaging technologies. The NexFET power block combines these two technologies to achieve higher levels of performance, and in half the space versus discrete MOSFETs. This article explains these new technologies and highlights their performance advantage.

关键词： MOSFET synchronous buck converters integration DC/DC converters.

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委内瑞拉1999年特大泥石流灾害

山地学报 2000年第6期18卷 580-582+584-585页

作者：韦方强,谢洪,Jose L.lopez,david Perez 中国科学院水利部成都山地灾害与环境研究所!四川成都610041 西南交通大学土木工程学院四川成都610031 中国科学院水利部成都山地灾害与环境研究所!四川成都610041 委内瑞拉中央大学流体力学研究所委内瑞拉环境部

受娜尼拉现象的影响 ,1 999-1 2 -1 5～ 1 6委内瑞拉北部阿维拉山区加勒比海沿岸的 8个州连降特大暴雨 ,造成山体大面积滑塌 ,数十条沟谷同时暴发大规模的泥石流。泥石流造成 3万人死亡 ,经济损失高达1 0 0亿美元 ,成为本世纪最严重的... 详细信息

受娜尼拉现象的影响 ,1 999-1 2 -1 5～ 1 6委内瑞拉北部阿维拉山区加勒比海沿岸的 8个州连降特大暴雨 ,造成山体大面积滑塌 ,数十条沟谷同时暴发大规模的泥石流。泥石流造成 3万人死亡 ,经济损失高达1 0 0亿美元 ,成为本世纪最严重的泥石流灾害。这次泥石流灾害具有群发性、规模大、低频率和直接入海等特点 ,对这类泥石流进行泥石流成因、活动规律、预测预报、泥石流与异常气候现象关系和直接入海型泥石流运动规律、沉积特征、对海水的污染扩散过程以及防治对策的研究具有重要意义

关键词：委内瑞拉泥石流灾害

Land use impacts on parasitic infection: a cross-sectional epidemiological study on the role of irrigated agriculture in schistosome infection in a dammed landscape

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Infectious Diseases of Poverty 2021年第2期10卷 78-78页

作者： Andrea J.Lund david HRehkopf Susanne HSokolow MMoustapha Sam Nicolas Jouanard Anne-Marie Schacht Simon Senghor Assane Fall Gilles Riveau Giulio ADe Leo david lopez-Carr Emmett Interdisciplinary Program in Environment and Resources Stanford University473 Via Ortega Suite 226StanfordCAUSA 不详

Background:Water resources development promotes agricultural expansion and food *** are these benefits offset by increased infectious disease risk?Dam construction on the Senegal River in 1986 was followed by agricultural expansion and increased transmission of human *** the mechanisms linking these two processes at the individual and household levels remain *** investigated the association between household land use and schistosome infection in children.

关键词： Agriculture Exposure Livelihoods Planetary health Senegal Schistosomiasis Water contact

阿姆斯特丹Conservatorium酒店

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设计家 2012年第1期 60-67页

作者： Daniel Knuttel piero lissoni davide cerini david lopez fabrizia bazzana carlo vedovello giovani giorgi michele bertoldini alberto massi mauri 赵如梦 Lissoni Associati工作室

结合了现代式与哥特式的conservatorum酒店是由荷兰建筑师DanielKnuttel在19世纪设计的，在成为阿姆斯特丹音乐学院（1983年——2003年）之前的77年里．

关键词：阿姆斯特丹酒店建筑师哥特式

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2型糖尿病与癌症：对观察性研究荟萃分析的同类系统性综述

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英国医学杂志中文版 2015年第9期18卷 483-483页

作者： Konstantinos K Tsilidis John C Kasimis david S lopez Evangelia E Ntzani John P A Ioannidis 任倩不详北京大学人民医院内分泌科

目的总结并评价2型糖尿病与癌症风险以及癌症死亡之间相关性的证据及证据的客观性。研究设计对2型糖尿病与癌症风险以及癌症死亡之间观察性研究的荟萃分析进行同类系统性综述。数据来源PubMed、Embass、Cochrane数据库的系统性综述，以... 详细信息

目的总结并评价2型糖尿病与癌症风险以及癌症死亡之间相关性的证据及证据的客观性。研究设计对2型糖尿病与癌症风险以及癌症死亡之间观察性研究的荟萃分析进行同类系统性综述。数据来源PubMed、Embass、Cochrane数据库的系统性综述，以及手工文献筛检。入选标准在人群中评价2型糖尿病与癌症风险或癌症死亡之间关系的观察性研究及其荟萃分析和系统性综述。

关键词： 2型糖尿病综述癌症

墨西哥的西尼罗河病毒∶自2002年7月以来大流行的证据

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中国人兽共患病学报 2004年第3期 269-269页

作者： Jose G.Estrada-Franco ,Robert Navarro-lopez ,david W.C.Beasley ,林春芳

Development and Evolution of the Size of Polygonal Fracture Systems during Fluid-Solid Separation in Clay-Rich Deposits

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Journal of Earth Science 2018年第6期29卷 1319-1334页

作者： Teodolina lopez Raphael Antoine JoséDarrozes Michel Rabinowicz david Baratoux CESBIO Universite de ToulouseCNES/CNRS/IRD/UPSloulousePrance International Space Science Institute(ISSI) BernSwitzerland CEREMA Laboratoire Regional de RouenGroupe Sciences de la TerreCS 90245F-76121 Le Grand QuevillyFrance GET Universite de ToulouseUPS/CNRS/IRD/CNESToulouseFrance Institut Fondamental d'Afrique Noire(IFAN) Cheikh Anta DioDakarSenegal

In continental and oceanic conditions, clay-rich deposits are characterised by the development of polygonal fracture systems（PFS）. PFS can increase the vertical permeability of clay-rich deposits（mean permeability ≤10-16 m2） and are pathways for fluids. On continents, the width of PFS ranges from centimeters to hundreds of meters, while in oceanic contexts they are up to a few kilometers large. These structures are linked to water-solid separation during deposition, consolidation and complete fluid squeeze of the clay horizon. During the last few decades, modeling of melt migration in partially molten plastic rocks led to rigorous quantifications of two-phase flows with a particular emphasis on 2D and 3D induced flow structures. The numerical modeling shows that the melt migrates on distances almost equal to a few times the compaction length L that depends on permeability and viscosity. Consequently, polygonal structures in partially molten plastic rocks are resulted from the melt-rock separation and their sizes are proportional to L. Applying these results to fluid-solid separation in clay-rich horizons, we show that（1） centimetric to kilometric PFS are resulted from the dramatic increase of L during compaction and（2）, this process involves agglomerates with 100 μm to 1 mm size.

关键词： compaction clay deposit agglomerates polygonal fractures desiccation cracks

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