223,198 research outputs found

    Highly efficient interfacing of guided plasmons and photons in nanowires

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    Successful exploitations of strongly confined surface plasmon-polaritons critically rely on their efficient and rapid conversion to lossless channels. We demonstrate a simple, robust, and broad-band butt-coupling technique for connecting a metallic nanowire and a dielectric nanofiber. Conversion efficiencies above 95% in the visible and close to 100% in the near infrared can be achieved with realistic parameters. Moreover, by combining butt-coupling with nanofocusing, we propose a broad-band high-throughput near-field optical microscope.Comment: 5 figure

    Segmented back-up bar Patent

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    Segmented back-up bar for butt welding large tubular structures such as rocket booster bodies or tank

    Structures in the Universe and Origin of Galaxies

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    The analysis of images (of obtained in various ranges of the lengths of waves) of luminous objects in the Universe by means of a method of multilevel dynamic contrasting led author to the conclusions: a) the structures of all observable galaxies represents a complicated constructions which have the tendency to self-similarity and made of separate (basic) blocks, which are a coaxially tubular structures and a cartwheel-like structures; b) the majority of observable objects in the Universe are luminous butt-ends of almost invisible (of almost completely transparent) of filamentary formations which structures are seen only near to their luminous butt-ends; c) the result of analysis of images of cosmic objects show the structure of many pairs of cooperating galaxies point to opportunity of their formation at butt-ends generated in a place of break of the similar filament; d) the interacting galaxies (M 81 and M 82) show they are butt-ends of sawed off of two branches of a treelike filament and their interaction is coming out through this filament; e) as our Universe is in dynamics the processes of formation of stars, galaxies and their congestions can go presently by means of a fracturing of filaments with a corresponding diameters and of the time for their such formation is necessary much less, than along existing standard model.Comment: 15 pages, 17 figures, the part of materials of given paper has been represented in Conf. "New Vistas in Physics of Dusty Plasmas",and published in AIP Proc. of this Conference, editors: Laifa Boufendi, Vfxime Mikikian, P.K. Shukla, v. 799 (2005), pp. 165-16

    Residual stress redistribution during elastic shake down in welded plates

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    Residual stresses are a consequence of welding in various structures such as ships and offshore structures. Residual stresses can be relaxed or redistributed according to the load levels during operation. The elastic shakedown phenomenon can be considered as one of the reasons for this change. This paper studies the relaxation/redistribution of weld residual stress during different levels of shakedown in a butt-welded plate chosen according to ship design and welding procedures. Welding was performed on DH36, a ship structural steel. Neutron diffraction was used to measure residual stresses in these plates in the as-welded state and after different levels of shakedown. A mixed hardening model in line with the Chaboche model is determined for both weld and base material. A numerical model is developed to estimate the shakedown limit on butt-welded plate. Further, the redistribution of residual stress in a numerical weld model according to the different levels of shakedown limit is studied. Based on the shakedown limit of the butt-welded plate, a shakedown region is determined, where the structure will undergo elastic shakedown in the presence of an existing residual stress field if the maximum stress on the load section after a few initial cycles is in the shakedown region

    A procedure for furnace brazing butt joints in tungsten-uranium dioxide cermet cylinders at 3000 deg C

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    Furnace brazing butt joints in tungsten-uranium dioxide cermet cylinders at 3000 deg

    Ultrasonic detection of flaws in fusion butt welds

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    Reliable and accurate Delta technique, a nondestructive ultrasonics method, uses redirection of energy to detect randomly oriented imperfections in fusion butt welds. Data on flaws can be read from either an oscilloscope or a printout

    The cooling of spent carbon anodes in the aluminium smelting industry : a thesis presented in partial fulfilment of the requirements for the degree of Master of Science in Mathematics at Massey University

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    As part of the New Zealand Aluminium Smelters (NZAS) upgrade, a hot butt cleaning system has been proposed, this would remove the bath from anodes as they are removed from the cells. It is expected that the time to cool for hot cleaned anodes would be significantly less than for current method of allowing the butts to cool before the bath is removed. In this project a mathematical model of the cooling process of both the clean and dirty anodes is developed. This model will aid in the investigation of the hot butt cleaning system by showing the difference in cooling times between the clean and dirty anodes. The temperature profiles within both clean and dirty anodes is calculated for one-, two- and three-dimensional models. Temperature changes in the anodes with time are also compared to experimental data

    The cooling of spent carbon anodes in the aluminium smelting industry : a thesis presented in partial fulfilment of the requirements for the degree of Master of Science in Mathematics at Massey University

    Get PDF
    As part of the New Zealand Aluminium Smelters (NZAS) upgrade, a hot butt cleaning system has been proposed, this would remove the bath from anodes as they are removed from the cells. It is expected that the time to cool for hot cleaned anodes would be significantly less than for current method of allowing the butts to cool before the bath is removed. In this project a mathematical model of the cooling process of both the clean and dirty anodes is developed. This model will aid in the investigation of the hot butt cleaning system by showing the difference in cooling times between the clean and dirty anodes. The temperature profiles within both clean and dirty anodes is calculated for one-, two- and three-dimensional models. Temperature changes in the anodes with time are also compared to experimental data
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