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Self-ordered porous anodic alumina (PAA) films are studied extensively due to a large number of possible applications in nanotechnology and low cost of production. Whereas empirical relationships between growth conditions and produced oxides have been established, fundamental aspects regarding pore formation and self-organization are still under debate. We present in situ structural studies of PAA

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The effect of surface strain on the passive film evolution of SAF 2507 super duplex stainless steel exposed to ambient air and 0.1 M NaCl solution with varying anodic polarization at room temperature has been investigated using in-situ grazing incidence X-ray diffraction (GIXRD) in combination with electrochemical measurements. Surface strain affected the crystallinity of the passive film as such

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Porous anodic alumina (PAA) can be used as a template for controlled electrodeposition and growth of nano-structures, it is also essential for long-lasting decorative coloring of aluminum. We have investigated the deposition of Sn nanopillars into PAA in-situ, with Grazing transmission small angle X-ray scattering, X-ray fluorescence and X-ray absorption near edge structure spectroscopy. An accumu

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The complexity of granular (geo-)materials is associated with the mobility and interaction of their constituent particles. Under the effect of loading, these materials exhibit a highly inhomogeneous behaviour, which might vary significantly as the loading develops (i.e. certain grain assemblies take up the load whilst other, neighbouring assemblies fall into states of lower load). To that end, und

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Urbanization has resulted in a gigantism of urban complexes and in many environmental and social problems. The situation on the surface and the principles of sustainable development compel urban planners to utilize the urban underground space, which for centuries has been almost exclusively the application field of mining. More often than not spatial planning in urban areas allocates various land-

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Weakly coupled relaxors based on compositions (1-x) BaTiO 3 -xBiMeO 3 , where Me is a metal ion, have attracted at

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The present paper deals with the time - dependent rock deformation during tunnelling, and more particularly, its association with the related phenomenon of creep in its viscoelastic form, as well as the numerical evaluation of it. Initially, a brief introduction of these two phenomena is provided. Then, the Burgers' idealized model of rheological rock mass behaviour is presented and analysed, alon

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Wealth is highly correlated between parents and their children; however, little is known about the extent to which these relationships are genetic or determined by environmental factors. We use administrative data on the net wealth of a large sample of Swedish adoptees merged with similar information for their biological and adoptive parents. Comparing the relationship between the wealth of adopte

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The rock mass viscous behaviour during tunnel construction is discussed. Initially, a brief introduction to the squeezing phenomenon and its association with the related one of creep is provided. Then, existing simplified models of rheological rock mass behaviour are presented and analysed. The range of the viscoelastic rock parameters identified in the literature for weak rocks is also given and

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Gold nanoparticles are of great interest for various nanoelectronic applications, e.g., for making single electron transistors or very fine leads to molecular size entities. For this and other applications, it is important that all particles have controllable size and shape. In this paper, we describe the production of size-selected gold aerosol particles in the 20 nm range made by evaporation in

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In this paper we investigate the feasibility of a fabrication route to produce nanocrystals of compound material with incongruent sublimation behavior via the simple evaporation of the powder of the compound. The generation of stoichiometric particles would only be possible if the particle formation occurs at temperatures below the incongruent sublimation point. Our experiments, done on three diff

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We have used carbon nanotubes to electrically contact a 7 nm gold particle by scanning-probe manipulation. The result was a single-electron transistor showing a periodic modulation of the current as a function of gate voltage for temperatures up to ∼200 K, with the particle responsible for the main features of the electron transport. This interpretation could be verified when the particle was remo

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We have developed a technique for the synthesis of size-selected, GaAs, epitaxial nano-whiskers, grown on a crystalline substrate. As catalysts, we used size-selected gold aerosol particles, which enabled us to fully vary the surface coverage independently of the whisker diameter. The whiskers were rod shaped, with a uniform diameter between 10 and 50 nm, correlated to the size of the catalytic se

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Arrangements of nanometer-sized particles were obtained on plane oxidized silicon substrates by direct deposition from the gas phase. The particles were attracted onto charge patterns created by contact charging. Monodisperse, singly charged indium aerosol particles with a diameter of 30 nm were used as a test case to illustrate this process. Due to the surface treatment, the deposition is highly

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Nanometer-sized particles of W are of interest in semiconductor device research, where such particles may store electrons inside heteroepitaxially defined structures. In this paper, we present results concerning W particles produced by thermal decomposition of tungsten hexacarbonyl. By the described method, it was possible to produce size-selected, single-crystalline W particles in the size range

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Nanocrystals of indium phosphide, with diameters of around 10nm, have been produced via an aerosol route. The method is based on the formation of monodisperse indium droplets and the subsequent reaction with phosphine at elevated temperature. The size of the final InP nanocrystal is self-limited by the size of the introduced size-selected In droplet. This size can be tuned carefully, thus this met

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Single-electron transistors (SET) rely for their functionality on extreme control of lithography and lateral positioning as well as of properties of the building blocks from which the devices are built. By an aerosol-based nanoparticle fabrication we can prepare nanocrystals down to sub-10nm dimensions with metallic or semiconducting character, as well as having a core + shell design for definitio