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41.
I. S. Bojii M. D. Filipovi Q. A. Parker J. L. Payne P. A. Jones W. Reid A. Kawamura Y. Fukui 《Monthly notices of the Royal Astronomical Society》2007,378(4):1237-1247
We present a new multiwavelength study of supernova remnant (SNR) B0513−692 in the Large Magellanic Cloud (LMC). The remnant also has a strong, superposed, essentially unresolved, but unrelated radio source at its north-western edge, J051324−691049. This is identified as a likely compact H ii region based on related optical imaging and spectroscopy. We use the Australia Telescope Compact Array (ATCA) at 4790 and 8640 MHz (λ≃ 6 cm and λ≃ 3.5 cm) to determine the large-scale morphology, spectral index and polarization characteristics of B0513−692 for the first time. We detect a strongly polarized region (49 per cent) in the remnant's southern edge (λ≃ 6 cm) . Interestingly, we also detect a small (∼40 arcsec) moderately bright, but distinct optical, circular shell in our Hα imagery which is adjacent to the compact H ii region and just within the borders of the north-eastern edge of B0513−692. We suggest that this is a separate new SNR candidate based on its apparently distinct character in terms of optical morphology in three imaged emission lines and indicative SNR optical spectroscopy (including enhanced optical [S ii ] emission relative to Hα). 相似文献
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Application of a modified UV-irradiation procedure to the fractionation of total dissolved phosphorus (TDP) in seawater was examined. By using a peristaltic pump, a sample solution was passed through a quartz column which was coiled around the three Hg-lamps and thus consistently exposed to a controlled UV-irradiation flux. The UV-flux was much lower than that historically employed to hydrolyze total dissolved organic phosphorus (DOP). Before and after the UV-irradiation, colorimetric measurements of soluble reactive phosphorus (SRP) were made by the method of Murphy and Riley (1962) to determine the liberation rate of orthophosphate from P-compounds in the sample. Experiments using 19 different P-compounds indicated that organic phosphate-esters containing only monomers of phosphate were readily decomposed by a 20-minute UV-irradiation period. Release of SRP from organic polyphosphates was minimal. The P released by this procedure is operationally referred to as UV-P. The procedure described herein was employed for fractionation of TDP in seawater. These studies defined several classes of dissolved P: (1) PO4–P(inorganic phosphate-P), (2) UV-P (Photodecomposable organic-P, most of which consists of organic monophosphate-P), and (3) Org-Poly-P (organic polyphosphate-P). Vertical profiles of DOP and UV-P observed in the oligotrophic regions of Suruga Bay and Antarctic Ocean indicated that UV-P was a major part of total dissolved phosphorus (TDP) in euphotic layers, where inorganic nutrients were probably limiting the active growth of phytoplankton. It is probable that UV-P can be utilized as a source of nutrient-P, in place of PO4–P. 相似文献
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Observations of the total lunar eclipse were made at 3.4-mm wavelength (87.4 GHz) on March 24, 1978. Eclipsr cooling curves with the best S/N ratio among those published thus far were obtained for the three points (the mountain area near the crater of Hipparuchus, Sinus Medii, and Copernicus). Each of the curves can be decomposed into the three parts which apparently correspond to ingress, totality, and egress. The derived cooling rate and heating rate differ significantly at the three points. 相似文献
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Summary ¶This paper outlines the development of a new expert system for assessing the applicability of tunnel boring machine (TBM) tunneling in Japan. Although a great deal of research on TBMs has been published, and the applicability of TBMs has been discussed, considerable differences in opinion still exist between authors. In this paper, we review previous studies and outline the present situation with particular focus on disc-cutter TBMs. Based on the knowledge acquired, we present an expert system for the applicability of TBMs, for use in pre-feasibility studies. Originally, we planned to construct the expert system on the basis of unified knowledge or rules without contradictions. However, it was found after several attempts that it is very difficult to unify knowledge because opinions vary considerably and TBMs are under continuous development. As a result, the expert system was divided into three stages. In stage A, the fulfillment of fundamental requirements is checked. Stage B is a simple expert system consisting of a minimal set of suitable rules as judged by the authors. Stage C incorporates the opinions of various other experts and the over-simplified and omitted points in stage B. The system is applied to 18 tunnels in Japan, and while the results provided by the expert system can certainly be improved, the method for accumulating knowledge and rules makes the system simple and easy to use, with very large scope for improvement and expansion.Received July 1, 2001; accepted December 9, 2002
Published online April 29, 2003 相似文献
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The galactic center radio lobe found in the radio continuum is interpreted as due to a channeled exhaust of material perpendicular to the galactic plane driven by an activity in the nuclear region. A common characteristic of the lobe to extragalactic more energetic jets is pointed out.Paper presented at the IAU Third Asian-Pacific Regional Meeting, held in Kyoto, Japan, between 30 September–6 October, 1984. 相似文献
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Summary. A constitutive equation is proposed in which the compliance is assumed to monotonically increase as a load is applied. The
primary feature of the constitutive equation is that the equation can be applied to various loading conditions such as constant
stress rate, constant strain rate, creep, or relaxation. The second feature is that the equation has exact solutions under
many loading conditions. The present paper shows the exact solutions for the constitutive equation and investigates the mutual
relationships between the exact solutions for the different loading conditions. The third feature is that it is comparatively
easy to find the constants in the constitutive equation. The present paper shows how to solve the constitutive equation for
the constants, and the constants for some native Japanese rocks. The constitutive equation used in the present paper is extremely
simple. Therefore, the equation can be easily implemented in almost any FEM code. It is likely that additional terms of the
constitutive equation will prove necessary for practical usage. However, additional terms can be found very easily by finding
higher-order approximations of experimental data. 相似文献