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Effect of negative permittivity and permeability on the transmission of electromagnetic waves through a structure containing left-handed material

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Natural Science 2011年第4期3卷 328-333页

作者： Muin F. Ubeid Mohammed M. Shabat Mohammed O. sid-Ahmed 不详

We investigate the characteristics of electromagnetic wave reflection and transmission by multilayered structures consisting of a pair of left-handed material (LHM) and dielectric slabs inserted between two semi-infinite dielectric media. The theoretical aspect is based on Maxwell's equations and matching the boundary conditions for the electric and magnetic fields of the incident waves at each layer interface. We calculate the reflected and transmitted powers of the multilayered structure taking into account the widths of the slabs and the frequency dependence of permittivity and permeability of the LHM. The obtained results satisfy the law of conservation of energy. We show that if the semi-infinite dielectric media have the same refractive index and the slabs have the same width, then the reflected (and transmitted) powers can be minimized (and maximized) and the powers-frequency curves show no ripple. On the other hand if the semi-infinite dielectric media have different values of refractive indices and the slabs have different widths, then under certain conditions the situation of minimum and maximum values of the mentioned powers will be reversed.

关键词： Electromagnetic Waves Left-Handed Materials Frequency Reflected and Transmitted Powers

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碰撞中的红牛

建筑实践 2012年第5期 93-97+92页

作者：张游 sid Lee

功能饮料红牛前不久委托sid Lee建筑事务所的设计阿姆斯特丹红牛新总部充满了撞击的力量,在这里,红牛寻找到了适合自己的新空间。新搬迁总部位于阿姆斯特丹北侧的港区,这里容易让人联想起艺术街头文化和极限运动。实际上,这里的前身为... 详细信息

功能饮料红牛前不久委托sid Lee建筑事务所的设计阿姆斯特丹红牛新总部充满了撞击的力量,在这里,红牛寻找到了适合自己的新空间。新搬迁总部位于阿姆斯特丹北侧的港区,这里容易让人联想起艺术街头文化和极限运动。实际上,这里的前身为一座造船厂,面对着一个似乎永恒不变的起重机和一个废弃的俄罗斯潜艇。

关键词：红牛阿姆斯特丹荷兰美术家建筑师造船厂

Redox Reactions Values of AlZn + Ag Eutectoid Chemical Composition

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Journal of Materials Science and Chemical Engineering 2014年第8期2卷 12-16页

作者： Socorro Valdez Jorge A. Ascencio Angélica Meneses sid R. Casolco Facultad de Farmacia Universidad Autónoma del Estado de Morelos Cuernavaca México Instituto de Ciencias Físicas Universidad Nacional Autónoma de México Cuernavaca México Instituto Tecnológico y de Estudios Superiores de Monterrey Vía Atlixcáyotl México

The effect of IB element additions [Ag] on the corrosion behavior of AlZn alloy has been investigated. The potentiodynamic polarization curves revealed that the corrosion behavior of SSAl, SSZn and AgZn3 phases was significantly influenced by IB element content. The electrochemical investigations showed that the corrosion rate increased with the IB-element additions. Furthermore, it was also evidenced the formation of a passive layer for the highest Ag content alloys;the passivity of this layer could be broken due to the presence of the intermetallic compound (IMCs) AgZn3.

关键词： AlZn Alloys Ag Additions Polarization Curve AgZn3 Precipitate

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消失中的森林

中国科技教育 2010年第6期 81-82页

作者： sid Perkins

一些人因为树的原因而看不到森林．但是对于许多人而言，他们看不到树，不是因为树不存在，而是因为这些树真的正处于消失中。一项卫星图像分析研究显示出，到2005年，世界森林的保有率比起2000年要减少了3％。

关键词：森林图像分析病虫害防护

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以爱之名——布宜诺斯艾利斯

人生十六七 2008年第4期 42-43页

作者： Fay sid

港湾……探戈……当夜晚来临时,寂静的海面上,唯有渔般的灯光点点闪烁,岸上、情调优雅的酒吧里传来阵阵"探戈"的响声。在这座充满浪漫的城市里,爱情悄然开始了。

关键词：阿根廷博尔赫斯爱情水手西班牙人酒吧意大利式故事闪烁情调

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矛盾的共鸣红牛阿姆斯特丹总部

室内设计与装修 2012年第3期 18-25页

作者： sid Lee Architecture sid Lee Architecture

2010年9月,希德李建筑事务所（sid Lee Architecture）和希德李建筑事务所位于阿姆斯特丹的工作室共同赢得了红牛品牌阿姆斯特丹总部办公室的设计权。5个月后,这个位于阿姆斯特丹的新总部落成了,又一次诠释了红牛品牌中对立统一的矛盾... 详细信息

2010年9月,希德李建筑事务所（sid Lee Architecture）和希德李建筑事务所位于阿姆斯特丹的工作室共同赢得了红牛品牌阿姆斯特丹总部办公室的设计权。5个月后,这个位于阿姆斯特丹的新总部落成了,又一次诠释了红牛品牌中对立统一的矛盾文化。

关键词：阿姆斯特丹红牛建筑事务所共鸣对立统一办公室工作室品牌

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The contribution of the European Society for Soil Conservation (ESSC) to scientific knowledge, education and sustainability

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International Soil and Water Conservation Research 2019年第1期7卷 102-107页

作者： Carmelo Dazzi Wim Comelis Edoardo A.C.Costantini Mihail Dumitru Michael A.Fullen Donald Gabriels Raimonds Kasparinskis Adam Kertész Giuseppe Lo Papa Guenola Pérès Jane Rickson JoséL.Rubio Thomas Sholten sid Theocharopoulos Ivan Vasenev Department of Agricultural Food and Forest SciencesUniversity of PalermoItaly Department of Environment University of GhentBelgium CREA-AA Research Centre for Agriculture and Environment Firenze/FlorenceItaly Institute for Soil Science Agrochemistry&Environment Protection ICPA BucharestRomania Faculty of Science and Engineering The University of WolverhamptonWV1 1LYUK UNESCO Chair on Eremology Faculty of Biosciences EngineeringGhent UniversityBelgium University of Latvia Faculty of Geography and Earth SciencesRigaLatvia Geographical Institute Research Centre for Astronomy and Earth SciencesHungarian Academy of SciencesBudapestHungary UMR SAS INRA Agrocampus 65 rue de Saint BrieucRennesFrance Cranfield Soil and AgriFood Institute Cranfield UniversityCranfieldUK IDE-CSIC Ctra Moncada-Naquera km 4.546113 MoncadaValenciaSpain Department of Geosciences Soil Science and GeomorphologyUniversity of TübingenGermany Hao-Demeter Institute of Soil and Water Resources14123 AthensGreece Ecology Department Russian State Agrarian UniversityTimiryazev Agricultural AcademyMoscowRussia

Soil is an integral component of the global environmental system which supports the quality and diversity of terrestrial life on ***,it is vital to consider the processes and impacts of soil degradation on society,especially on the provision of environmental goods and services,including food security and climate change mitigation and *** societies devoted to soil science play significant roles in reducing soil degradation and promoting soil conservation by advancing scientificknowledge,education and environmental *** ESSC was founded on 4 November 1988,with the aims to:*** research on soil degradation,soil protection and soil and water *** a network for the exchange of knowledge about soil degradation processes and soil conservation research and *** publications on major issues relating to soil degradation and soil and water *** regulators and policy-makers on soil issues,especially soil degradation,protection and *** societal challenges that can be addressed through better soil protection,advancing knowledge and scientific approaches to soil protection and sustainable management,mean the ESSC embraces the on-going development,application,review and constructive criticism of highly innovative scientific soil conservation methods,In this context,the ESSC analyses and publicizes the roles and functions of soil in natural and human-modified systems and the functional optimization of soils to ensure sustainable environmental protection.'The thin layer of soil that forms a patchy covering over the continents controls our awn existence and that of every other animal of the land' (Rachel Carson (1962) in'Silent Spring).

关键词： Soil degradation Soil education Soil functions Soil health Soil knowledge