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[en] The past size and location of the hypothesized proto-South China Sea vanished ocean basin has important plate-tectonic implications for Southeast Asia since the Mesozoic. Here we present new details on proto-South China Sea paleogeography using mapped and unfolded slabs from tomography. Mapped slabs included: the Eurasia-South China Sea slab subducting at the Manila trench; the northern Philippine Sea Plate slab subducting at the Ryukyu trench; and, a swath of detached, subhorizontal, slab-like tomographic anomalies directly under the South China Sea at 450 to 700 km depths that we show is subducted ‘northern proto-South China Sea’ lithosphere. Slab unfolding revealed that the South China Sea lay directly above the ‘northern Proto-South China Sea’ with both extending 400 to 500 km to the east of the present Manila trench prior to subduction. Our slab-based plate reconstruction indicated the proto-South China Sea was consumed by double-sided subduction, as follows: (1) The ‘northern proto-South China Sea’ subducted in the Oligo–Miocene under the Dangerous Grounds and southward expanding South China Sea by in-place ‘self subduction’ similar to the western Mediterranean basins; (2) limited southward subduction of the proto-South China Sea under Borneo occurred pre-Oligocene, represented by the 800–900 km deep ‘southern proto-South China Sea’ slab.
[en] The AFIP-6 (ATR Full-size-plate In center flux trap Position) Characterization Summary Report outlines the fresh fuel characterization efforts performed during the AFIP-6 experiment. The AFIP-6 experiment was designed to evaluate the performance of monolithic uranium-molybdenum (U-Mo) fuels at a scale prototypic of Advanced Test Reactor (ATR) fuel plates (45-inches long). The AFIP-6 test was the first test with plates that were swaged into the rails of the assembly. This test served to examine the effects of a plate in a swaged condition with longer fuel zones (22.5-inches long), that were centered in the plate. AFIP-6 test plates employed a zirconium interlayer that was co-rolled with the fuel foil. Previous mini-plate and AFIP irradiation experiments performed in ATR have demonstrated the stable behavior of the interface between the U-Mo fuel and the zirconium interlayer.
[en] The AFIP-4 (ATR Full -size-plate In center flux trap Position) experiment was designed to evaluate the performance of monolithic fuels at a scale prototypic of research reactor fuel plates. Twelve qualified fueled plates were fabricated for the AFIP-4 experiment; to be irradiated in the INL Advanced Test Reactor (ATR). This report provides details of the fuel fabrication efforts; including material selection, fabrication processes, and fuel plate qualification.
[en] For the failure of a low-temperature globe valve, through disassembly and material analysis, the cause of the failure was initially determined to be caused by adhesive wear between the disc guide rod and the valve seat. From the three aspects of material detection, stress and adhesive wear, the failure mechanism of stainless steel motion pair was analyzed. Finally, the wear test was carried out for chrome plating and non-chromium plating. Tests showed that when the valve seat is chrome-plated, the surface hardness of the guide portion is increased, which could effectively prevent the adhesive wear failure of the guide rod and the valve seat guide hole. (paper)
[en] On the Moon and Mars olivine of probable mantle origin is detected at rims of large Late Heavy Bombardment (LHB) age impact basins for which excavation depth estimates exceed crustal thickness estimates. But lunar Crisium size impact basins are not recognized on Earth nor expected in the Phanerozoic from conventional interpretations of crater size frequency distributions. In this study several large circular to elliptical basin structures on Earth, for which hypothesized impact excavation depth would greatly exceed crustal thickness, are examined for the presence of exposed lithospheric mantle, expressed as ophiolite, at the rims. Three Phanerozoic impact basins, modified by plate tectonics and tentatively correlated with “ophiolite obduction” plus global extinction events, are proposed here. These tentatively suggested Phanerozoic impact basins are: (1) Yucatan Basin/Puerto Rico Trench with a Greater Antilles ophiolite rim. Cretaceous-Paleogene Boundary global extinction may correlate with Maastrichtian ophiolite obduction in Southeast Cuba. (2) Loyalty Basin with a New Caledonia ophiolite plus d’Entrecasteaux Ridge rim. Late Eocene global extinction may correlate with obduction of the New Caledonia Peridotite Nappe. (3) Sulu Sea Basin with a Palawan, Sabah etc. ophiolite rim. The Middle Miocene Disruption Event may correlate with ophiolite obduction plus ophiolitic mélange emplacement in Sabah and in Palawan. These originally circular to elliptical belts of exposed lithospheric mantle may serve as strain markers for relative plate motions in the vicinity of plate boundaries during post-impact geologic times. It is further speculated that plate boundaries may be initiated and/or modified by such impacts.
[en] The first fuel plate frame assembly of the AFIP-6 MKII experiment was irradiated as planned from December, 2011 through February, 2012 in the center flux trap of the Advanced Test Reactor during cycle 151A. Following irradiation in this cycle and while reconfiguring the experiment in the ATR canal, a non-fueled component (the bottom plate) of the first fuel plate frame assembly became separated from the rail sides. There is no evidence that the fueled region of the fuel plate frame assembly was compromised by this incident or the irradiation conditions. The separation of this component was determined to have been caused by flow induced vibrations, where vortex shedding frequencies were resonant with a natural frequency of the bottom plate component. This gave way to amplification, fracture, and separation from the assembly. Although parallel flow induced vibrations were analyzed, vortex shedding flow induced vibrations was an unfamiliar failure mode that was difficult to identify. Both the once-irradiated first fuel plate and un-irradiated second fuel plate frame assemblies were planned for irradiation in the subsequent cycle 151B. The AFIP-6 MKII experiment was excluded from irradiation in cycle 151B because non-trivial design modifications would be needed to mitigate this type of incident during the second irradiation cycle. All items of the experiment hardware were accounted for and cycle 151B occurred with a non-fueled AFIP backup assembly in the center flux trap. Options for completion of the AFIP-6 MKII experiment campaign are presented and future preventative actions are recommended.
[en] The Advanced Test Reactor (ATR) Full-size Plate In Center Flux Trap Position (AFIP)-2 experiment was designed to evaluate the performance of monolithic fuels at a scale prototypic of research reactor fuel plates. Two qualified fueled plates were fabricated for the AFIP 2 experiment to be irradiated in the Idaho National Laboratory ATR. This report provides details of the fuel fabrication efforts, including material selection, fabrication processes, and fuel plate qualification.
[en] Clad steel used in constructions exposed to severe corrosion conditions. Roll cladding, explosion cladding, and hot rolling of explosion clad slabs as a means of manufacture. Further development through improvement processing and service properties. Base metal for quenched and tempered clad plate. Possibilities for new combinations with austenitic, austenitic-ferritic, and ferritic super stainless steels. (orig.)
[de]Plattierte Staehle als Konstruktionswerkstoffe fuer schwierige Beanspruchungsbedingungen. Walzplattieren, Sprengplattieren und Warmwalzen von vorgesprengtem Halbzeug als Fertigungsverfahren. Weiterentwicklung durch verbesserte Verarbeitungs- und Gebrauchseigenschaften. Grundwerkstoff fuer wasserverguetete Plattierungen. Neue Kombinationsmoeglichkeiten mit austenitischen, austenitisch-ferritischen und ferritischen nichtrostenden Sonderstaehlen. (orig.)
[en] Microspheres coated with a perfectly conductive surface have many advantages in the applications of biosensors and micro-electromechanical systems. Polystyrene microspheres with the diameter of 10 μm were coated with a 50 nm-thick gold layer using an electroless gold plating approach. Dielectrophoresis (DEP) for bare microspheres and shelled microspheres was theoretically analysed and the real part of the Clausius—Mossotti factor was calculated for the two kinds of microspheres. The experiments on the dielectrophoretic characterisation of the uncoated polystyrene microspheres and gold coated polystyrene microspheres (GCPMs) were carried out. Experimental results showed that the gold coated polystyrene microspheres were only acted by a positive dielectrophoretic force when the frequency was below 40M Hz, while the uncoated polystyrene microspheres were governed by a negative dielectrophoretic force in this frequency range. The gold coated polystyrene microspheres were exploited to form the microwire automatically according to their stable dielectrophoretic and electric characterisations. (condensed matter: electronic structure, electrical, magnetic, and optical properties)
[en] The AFIP-6 (ATR Full-size plate In center flux trap Position) experiment was designed to evaluate the performance of monolithic fuels at a scale prototypic of research reactor fuel plates. Two qualified fueled plates were fabricated for the AFIP-6 experiment; to be irradiated in the INL Advanced Test Reactor (ATR). This report provides details of the fuel fabrication efforts, including material selection, fabrication processes, and fuel plate qualification.