1,060 research outputs found
Theory of two-dimensional macroscopic quantum tunneling in a Josephson junction coupled with an LC circuit
We investigate classical thermal activation (TA) and macroscopic quantum
tunneling (MQT) for a Josephson junction coupled with an LC circuit
theoretically. The TA and MQT escape rate are calculated analytically by taking
into account the two-dimensional nature of the classical and quantum phase
dynamics. We find that the MQT escape rate is largely suppressed by the
coupling to the LC circuit. On the other hand, this coupling gives rise to
slight reduction of the TA escape rate. These results are relevant for the
interpretation of a recent experiment on the MQT and TA phenomena in grain
boundary YBCO Josephson junctions.Comment: 4 pages, 1 figure, Proceedings of LT2
Output-Based Allocation of Emissions Permits for Mitigating the Leakage and Competitiveness Issues for the Japanese Economy
The adoption of domestic emissions trading schemes (ETS) can impose a heavy burden on energy-intensive industries. In particular, energy-intensive industries competing with foreign competitors could lose their international edge. Although the abatement of carbon dioxide (CO2) emissions in industrialized countries entails the reduction of their energy-intensive production, a corresponding increase in the production of energy-intensive goods in countries without CO2 regulations may lead to carbon âleakage.â This paper examines the effects of various allocation methods for granting emissions permits in the Japanese ETS on the economy and CO2 emissions using a multiregional and multisector computable general equilibrium model. Specifically, we apply the Fischer and Fox (2007) model to the Japanese economy to address carbon leakage and competitiveness issues. We compare auction schemes, grandfathering schemes, and output-based allocation (OBA) schemes. We further extend the model by examining a combination of auctions and OBA. Though the auction scheme is found to be the best in terms of macroeconomic impacts (welfare and GDP effects), the leakage rate is high and the harm to energy-intensive sectors can be significant. OBA causes less leakage and damage to energy-intensive sectors, but the macroeconomic impact is undesirable. Considering all three effectsâleakage, competitiveness, and macroeconomicsâwe find that combinations of auctions and OBA (with gratis allocations solely to energy-intensive, trade-exposed sectors) are desirable.climate change, emissions trading, emissions permit allocations, output-based allocation, auction, grandfathering, international competitiveness, carbon leakage, CGE analysis
Social structure and reproduction of long-tailed porcupine (Trichys fasciculata)
We studied the social structure of long-tailed porcupine (Trichys fasciculata) in the tropical rainforest in Sabah, Borneo Island, Malaysia via direct observation assisted by radio-tracking and camera-trapping at burrow entrances. We identified and observed seven individuals in the study area, of which five were radio-tagged. Analysis of their burrow use, home range, and behaviour strongly suggested that five of the observed individuals formed a family group consisting of an adult maleâfemale pair and their three offspring, two of which were born during the study period. The family members used the same burrow site almost every day, and their home ranges largely overlapped. In contrast, the other two individuals never used the burrow sites of this family group. The adult maleâfemale pair was maintained for at least 18 months and reproduced twice during the study period. They had a litter size of one, and the inter-litter interval was estimated to be 11 months. During these two reproductions, the previous litter stayed in the natal family group as a sub-adult after the next juvenile was born. Direct paternal care, such as grooming the juvenile, was also observed. Their low reproductive potential should be considered in conservation efforts
Effect of zero energy bound states on macroscopic quantum tunneling in high-Tc superconductor junctions
The macroscopic quantum tunneling (MQT) in the current biased high-Tc
superconductor Josephson junctions and the effect of the zero energy bound
states (ZES) on the MQT are theoretically investigated. We obtained the
analytical formula of the MQT rate and showed that the presence of the ZES at
the normal/superconductor interface leads to a strong Ohmic quasiparticle
dissipation. Therefore, the MQT rate is noticeably inhibited in compared with
the c-axis junctions in which the ZES are completely absent.Comment: 4 pages, 1 figure, comment and reference about recent experiment
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Numerical study of pi-junction using spin filtering barriers
We numerically investigate the Josephson transport through ferromagnetic
insulators (FIs) by taking into account its band structure. By use of the
recursive Green's function method, we found the formation of the pi junction in
the case of the fully spin-polarized FI (FPFI), e.g., LaBaCuO.
Moreover, the 0-pi transition is induced by increasing the thickness of FPFI.
On the other hand, Josephson current through the Eu chalcogenides shows the pi
junction behavior in the case of the strong d-f hybridization between the
conduction d and the localized f electrons of Eu. Such FI-based Josephson
junctions may become a element in the architecture of future quantum
information devices.Comment: 9 pages, 5 figure
Polar surface engineering in ultra-thin MgO(111)/Ag(111) -- possibility of metal-insulator transition and magnetism
A recent report [Kiguchi {\it et al.}, Phys. Rev. B {\bf 68}, 115402 (2003)]
that the (111) surface of 5 MgO layers grown epitaxially on Ag(111) becomes
metallic to reduce the electric dipole moment raises a question of what will
happen when we have fewer MgO layers. Here we have revealed, first
experimentally with electron energy-loss spectroscopy, that MgO(111) remains
metallic even when one-layer thick, and theoretically with the density
functional theory that the metallization should depend on the nature of the
substrate. We further show, with a spin-density functional calculation, that a
ferromagnetic instability may be expected for thicker films.Comment: 5 pages, 7 figure
Different photochemical behavior of bis(biphenyl)ethylenes and ethenes in solution and in the solid-state: Structurally controlled Z/E-photoisomerization in the solid-state
ArticleJOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY A-CHEMISTRY. 184(1-2): 44-49 (2006)journal articl
SixâAxis Ground Motion Measurements of Caldera Collapse at KÄ«lauea Volcano, Hawai'iâMore Data, More Puzzles?
Nearâfield recordings of large earthquakes and volcanoâinduced events using traditional seismological instrumentation often suffer from unaccounted effects of local tilt and saturation of signals. Recent hardware advances have led to the development of the blueSeisâ3A, a very broadband, highly sensitive rotational motion sensor. We installed this sensor in close proximity to permanently deployed classical instrumentation (i.e., translational seismometer, accelerometer, and tiltmeter) at the Hawaiian Volcano Observatory (USGS). There, we were able to record three ~Mw 5 earthquakes associated with large collapse events during the later phase of the 2018 KÄ«lauea summit eruption. Located less than 2 km from the origins of these sources, the combined sixâaxis translational and rotational measurements revealed clear static rotations around all three coordinate axes. With these six component recordings, we have been able to reconstruct the complete time history of ground motion of a fixed point during an earthquake for the first time
Reconstruction of the biogeochemistry and ecology of photoautotrophs based on the nitrogen and carbon isotopic compositions of vanadyl porphyrins from Miocene siliceous sediments
We determined both the nitrogen and carbon isotopic compositions of various vanadyl alkylporphyrins isolated from siliceous marine sediments of the Onnagawa Formation (middle Miocene, northeastern Japan) to investigate the biogeochemistry and ecology of photoautotrophs living in the paleo-ocean. The distinctive isotopic signals support the interpretations of previous works that the origin of 17-nor-deoxophylloerythroetioporphyrin (DPEP) is chlorophylls-<i>c</i><sub>1-3</sub>, whereas 8-nor-DPEP may have originated from chlorophylls-<i>a</i><sub>2</sub> or <i>b</i><sub>2</sub> or bacteriochlorophyll-<i>a</i>. Although DPEP and cycloheptanoDPEP are presumably derived from common precursory pigments, their isotopic compositions differed in the present study, suggesting that the latter represents a specific population within the photoautotrophic community. The average &delta;<sup>15</sup>N value for the entire photoautotrophic community is estimated to be &ndash;2 to +1&permil; from the &delta;<sup>15</sup>N values of DPEP (&ndash;6.9 to &ndash;3.6&permil;; <i>n</i>=7), considering that the empirical isotopic relationships that the tetrapyrrole nuclei of chloropigments are depleted in <sup>15</sup>N by ~4.8&permil; and enriched in <sup>13</sup>C by ~1.8&permil; relative to the whole cells. This finding suggests that nitrogen utilized in the primary production was supplied mainly through N<sub>2</sub>-fixation by diazotrophic cyanobacteria. Based on the &delta;<sup>13</sup>C values of DPEP (&ndash;17.9 to &ndash;15.6&permil;; <i>n</i>=7), we estimated isotopic fractionation associated with photosynthetic carbon fixation to be 8&ndash;14&permil;. This range suggests the importance of &beta;-carboxylation and/or active transport of the carbon substrate, indicating in turn the substantial contribution of diazotrophic cyanobacteria to primary production. Based on the &delta;<sup>15</sup>N values of 17-nor-DPEP (&ndash;7.4 to &ndash;2.4&permil; <i>n</i>=7), the &delta;<sup>15</sup>N range of chlorophylls-<i>c</i>-producing algae was estimated to be &ndash;3 to +3&permil;. This relative depletion in sup>15</sup>N suggests that these algae mainly utilized nitrogen regenerated from diazotrophic cyanobacteria. Given that diatoms are likely to have constituted the chlorophylls-<i>c</i>-producing algae within the biogenic-silica-rich Onnagawa Formation, cyanobacteria-hosting diatoms may have been important contributors to primary production
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