Three-dimensional density measurement of unsteady flow field around a sphere is carried out in the ballistic range at Institute of Fluid Science, Tohoku University. Simultaneous multi-angle measurement system using tw...Three-dimensional density measurement of unsteady flow field around a sphere is carried out in the ballistic range at Institute of Fluid Science, Tohoku University. Simultaneous multi-angle measurement system using twelve digital cameras is installed in the test chamber of the ballistic range to achieve the three-dimensional density measurement. The Colored-Grid Background Oriented Schlieren (CGBOS) technique using colored-grid background is utilized for the reconstruction of density. The Mach number of the sphere is set to 1.5. The short pulse LEDs to illuminate the backgrounds are also installed in the chamber to capture the unsteady flow field around a flying sphere. Three-dimensional density distribution around a sphere is successfully reconstructed.展开更多
The search for the ri_(13/2) vi_(13/2 ) band in ^(178)Ir has been conducted through the ^(152)Sm(^(31) P, 5nγ)^( 178)Ir reaction and the excitation functions, x-γ and γ-γ-t coincidence measurements. Five rotationa...The search for the ri_(13/2) vi_(13/2 ) band in ^(178)Ir has been conducted through the ^(152)Sm(^(31) P, 5nγ)^( 178)Ir reaction and the excitation functions, x-γ and γ-γ-t coincidence measurements. Five rotational bands have been newly identified. The low-spin signature inversion in the πi13/2 vi13/2 band has been confirmed by the observations of linking transitions and signature crossing at I = 25.5 h. The inversion phenomenon in rh11/2 vi_(13/2), rh9/2 vi_(13/2) and ri_(13/2) vi13/2 structures in ^(178)Ir provides a unique testing ground for different theoretical interpretations.展开更多
For the measurement of atmospheric NO2 vertical column density (VCD), Kitt Peak Solar Flux Atlas can be substituted as an extraterrestrial solar radiation. Compared with differential analysis method, the Taylor expans...For the measurement of atmospheric NO2 vertical column density (VCD), Kitt Peak Solar Flux Atlas can be substituted as an extraterrestrial solar radiation. Compared with differential analysis method, the Taylor expansion of integrated transfer equation underestimates the VCD. This underestimation is as large as 35% when the amount of NO2 is 1 × 1017 cm?2 and observation is conducted with an air mass factor of 10. Even when the VCD is 2 × 1016 cm?2 and the air mass factor is 4, the relative error of the retrieved VCD is still no less than 3%. If the observation is restricted under the small air mass factor condition (≤ 4), with Kitt Peak Solar spectrum as an extraterrestrial solar radiation, only an atmospheric layer of 2 km thick from ground can be studied, which will make the absorption too weak to be detected by normal instruments. The VCD in winter Tokyo area was observed and analyzed by differential method, which shows a good precision even when the absorption is as low as 3%. The largest average VCD was about 1.3 × 1017 cm-2, and the lowest was about 1.3 × 1016 cm?2. The trend of its variation was almost the same as the ground level observation by Saltzman reagent method. Key words Vertical column density (VCD) - Extraterrestrial solar radiation - NO2 - Atmospheric contamination展开更多
The high-spin level structure of 186 Au is re-investigated by means of in-beam γ-ray spectroscopy via the 172 Yb(19 F,5nγ )186 Au reaction.The oblate bands previously reported are revised and extended to higher-spin...The high-spin level structure of 186 Au is re-investigated by means of in-beam γ-ray spectroscopy via the 172 Yb(19 F,5nγ )186 Au reaction.The oblate bands previously reported are revised and extended to higher-spin states.A new Iπ =(20+) excited state has been identified and assigned to the πh-111/2 (×) vi-213/2h-19/2 configuration.The total Routhian surface and cranked shell model calculations suggest that the πh-111/2 (×) vi-213/2h-19/2 band in 186Au has a non-axial deformation.展开更多
High-spin states in 178'180Ir have been studied via the 152'154Sm(31P,5nγ)reactions through excitation functions,x-γandγ-γ-t coincidence measurements.A doubly decoupled band has been identified in each of ...High-spin states in 178'180Ir have been studied via the 152'154Sm(31P,5nγ)reactions through excitation functions,x-γandγ-γ-t coincidence measurements.A doubly decoupled band has been identified in each of the isotopes.The level spacings for such structures in odd-odd ^(178-186)Ir have been inspected and thus a regular level staggering as a function of the neutron number is revealed.This particular phenomenon may be associated with bandmixing at lower excitation energies.展开更多
We give a lower bound of the Loewy length of the projective cover of the trivial module for the group algebra kG of a finite group G of Lie type defined over a finite field of odd characteristic p, where k is an arbit...We give a lower bound of the Loewy length of the projective cover of the trivial module for the group algebra kG of a finite group G of Lie type defined over a finite field of odd characteristic p, where k is an arbitrary field of characteristic p. The proof uses Auslander-Reiten theory.展开更多
文摘Three-dimensional density measurement of unsteady flow field around a sphere is carried out in the ballistic range at Institute of Fluid Science, Tohoku University. Simultaneous multi-angle measurement system using twelve digital cameras is installed in the test chamber of the ballistic range to achieve the three-dimensional density measurement. The Colored-Grid Background Oriented Schlieren (CGBOS) technique using colored-grid background is utilized for the reconstruction of density. The Mach number of the sphere is set to 1.5. The short pulse LEDs to illuminate the backgrounds are also installed in the chamber to capture the unsteady flow field around a flying sphere. Three-dimensional density distribution around a sphere is successfully reconstructed.
基金Supported by the National Natural Science Foundation of China under Grant Nos.10025525 and 19605008the Japan STA Scientist Exchange Programme,the JSPS Invitation Fellowship Programme for Research in Japan under Grant No.L00515the Major State Basic Research Development Programme of China(Contract No.G2000077400).
文摘The search for the ri_(13/2) vi_(13/2 ) band in ^(178)Ir has been conducted through the ^(152)Sm(^(31) P, 5nγ)^( 178)Ir reaction and the excitation functions, x-γ and γ-γ-t coincidence measurements. Five rotational bands have been newly identified. The low-spin signature inversion in the πi13/2 vi13/2 band has been confirmed by the observations of linking transitions and signature crossing at I = 25.5 h. The inversion phenomenon in rh11/2 vi_(13/2), rh9/2 vi_(13/2) and ri_(13/2) vi13/2 structures in ^(178)Ir provides a unique testing ground for different theoretical interpretations.
文摘For the measurement of atmospheric NO2 vertical column density (VCD), Kitt Peak Solar Flux Atlas can be substituted as an extraterrestrial solar radiation. Compared with differential analysis method, the Taylor expansion of integrated transfer equation underestimates the VCD. This underestimation is as large as 35% when the amount of NO2 is 1 × 1017 cm?2 and observation is conducted with an air mass factor of 10. Even when the VCD is 2 × 1016 cm?2 and the air mass factor is 4, the relative error of the retrieved VCD is still no less than 3%. If the observation is restricted under the small air mass factor condition (≤ 4), with Kitt Peak Solar spectrum as an extraterrestrial solar radiation, only an atmospheric layer of 2 km thick from ground can be studied, which will make the absorption too weak to be detected by normal instruments. The VCD in winter Tokyo area was observed and analyzed by differential method, which shows a good precision even when the absorption is as low as 3%. The largest average VCD was about 1.3 × 1017 cm-2, and the lowest was about 1.3 × 1016 cm?2. The trend of its variation was almost the same as the ground level observation by Saltzman reagent method. Key words Vertical column density (VCD) - Extraterrestrial solar radiation - NO2 - Atmospheric contamination
基金Supported by the National Natural Science Foundation of China under Grant Nos 10905075,10825522,10735010,and 10975006the National Basic Research Program of China under Grant No 2007CB815005the Chinese Academy of Sciences.
文摘The high-spin level structure of 186 Au is re-investigated by means of in-beam γ-ray spectroscopy via the 172 Yb(19 F,5nγ )186 Au reaction.The oblate bands previously reported are revised and extended to higher-spin states.A new Iπ =(20+) excited state has been identified and assigned to the πh-111/2 (×) vi-213/2h-19/2 configuration.The total Routhian surface and cranked shell model calculations suggest that the πh-111/2 (×) vi-213/2h-19/2 band in 186Au has a non-axial deformation.
基金Supported by Japan STA(Science and Technology Agency)Scientist Exchange Program(Grant No.1998-21)the National Natrural Science Foundation of China under Grant No.19605008.
文摘High-spin states in 178'180Ir have been studied via the 152'154Sm(31P,5nγ)reactions through excitation functions,x-γandγ-γ-t coincidence measurements.A doubly decoupled band has been identified in each of the isotopes.The level spacings for such structures in odd-odd ^(178-186)Ir have been inspected and thus a regular level staggering as a function of the neutron number is revealed.This particular phenomenon may be associated with bandmixing at lower excitation energies.
基金the Japan Society for Promotion of Science （JSPS）, Grant-in-Aid for Scientific Research （C）15K04776, 2015-2018, and by the CIB in EPFL. The second author was supported by the German Science Foundation （DFG） Scientific Priority Programme SPP-1489 ＂Algorithmic and Experimental Methods in Algebra, Geometry, and Number Theory＂.
文摘We give a lower bound of the Loewy length of the projective cover of the trivial module for the group algebra kG of a finite group G of Lie type defined over a finite field of odd characteristic p, where k is an arbitrary field of characteristic p. The proof uses Auslander-Reiten theory.
