《La France considère que les changements accomplis ou en voie de l’être , depuis 1949 , en Europe , en Asie et ailleurs , ainsi que l’évolution de sa propre situation et de ses propres
《La France considère que les changements accomplis ou en voie de l’être , depuis 1949 , en Europe , en Asie et ailleurs , ainsi que l’évolution de sa propre situation et de ses propres
2008年,这一刻,我们的地球怎样了?《明日风尚》在内地华文媒体之中,首先取得《法国世界外交论衡月刊》(Le Monde Diplomatique)特别授权,辑录了该国际性月刊今年推出的"世界地图集",以大量地图和图表,向华文读者展现我们地球的最新状况...
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2008年,这一刻,我们的地球怎样了?《明日风尚》在内地华文媒体之中,首先取得《法国世界外交论衡月刊》(Le Monde Diplomatique)特别授权,辑录了该国际性月刊今年推出的"世界地图集",以大量地图和图表,向华文读者展现我们地球的最新状况。地球明显盛载着战争、疾病、贫穷、疯狂和环境破坏。我们从"天视"的角度去俯瞰地球,不出我们所料,地球形势叫人不安。深海水产遭到可以装下整座巴黎铁塔的渔网的无情扫荡。森林采伐、疯狂贸易,进一步导致地球气温攀升。水源匮乏进入了五十年倒数的灾难阶段。紧接着令人忧心忡忡的基因改造生物技术,这年头,我们又迎来了"微不足道"同时危险莫测的"纳米科技"。文明国家可以联合起来做些什么吗?对不起,我们发现国际上普遍存在企业环保责任的"司法空白"。跨国企业一方面牟取暴利肆意破坏环境,一方面展开"伪绿色宣传",为企业形象"整容"。原来"国有国法,家有家规"之外,我们并没有一条"地球法"。"生物多样性"正呈现明显衰退,远古出现过五次大规模生物灭绝,现在我们是否已踏进第六波生物灭绝?下一页,你将从"地球人视角"看到宏观的世界。——编者——
Strain engineering is a powerful tool to tailor the physical properties of materials coherently stacked in an epitaxial heterostructure. Such an approach, applied to the mature field of planar heteroepitaxy, has yield...
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Strain engineering is a powerful tool to tailor the physical properties of materials coherently stacked in an epitaxial heterostructure. Such an approach, applied to the mature field of planar heteroepitaxy, has yielded a variety of new phenomena and devices. Recently, heteroepitaxial vertically aligned nanocomposites have emerged as alternatives to planar structures. Owing to the peculiar geometry of such nanoarchitectures, efficient strain control can be achieved, opening the way to novel functionalities. In this paper, we report a very large tensile axial strain in epitaxial transition metal nanowires embedded in an oxide matrix. We show that axial strains in excess of 1.5% can be sustained over a large thickness (a few hundred nanometers) in epitaxial nanowires having ultrasmall diameters (-3-6 nm). The axial strain depends on the diameter of the nanowires, reflecting its epitaxial nature and the balance of interface and elastic energies. Furthermore, it is experimentally shown that such strain is metastable, in agreement with the calculations performed in the framework of the Frenkel-Kontorova model. The diameter dependence and metastability provide effective ways to control the strain, an appealing feature for the design of functional nanoarchitectures.
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