The Izu-Bonin subduction zone in the Northwest Pacific is an ideal location for understanding mantle dynamics such as cold lithosphere subduction. The slab produces a lateral thermal anomaly, inducing local topographi...The Izu-Bonin subduction zone in the Northwest Pacific is an ideal location for understanding mantle dynamics such as cold lithosphere subduction. The slab produces a lateral thermal anomaly, inducing local topographic changes at the boundary of a post-spinel phase transformation, considered to be the origin of the ‘660-km discontinuity.’ In this study, the short-period(1–2 Hz) S-to-P conversion phase S660P was used to obtain the fine-scale structure of the discontinuity. More than 100 earthquakes that occurred from the 1980s to the 2020s and were recorded by high-quality seismic arrays in the United States and Europe were analyzed. A discontinuity in the ambient mantle with an average depth of ~670 km was found beneath the 300–400-km event zone in the northern Bonin region near 33°N. Meanwhile, the ‘660-km discontinuity’ has been pushed upward, away from the slab, possibly because of a hot upwelling mantle plume. In the central part of the subduction zone, the 660-km discontinuity is depressed to an average depth of(690 ± 5) km within the slab at approximately 150 km below the coldest slab core, indicating a(300 ± 100) ℃ cold anomaly estimated using a post-spinel transformation Clapeyron slope of(-2.0 ± 1.0) MPa/K. In southern Bonin near 28°N, the discontinuity was found to be further depressed at an average depth of(695 ± 5) km below the deepest event and with a focal depth of ~550 km. The discontinuity is located where the slab bends abruptly to become sub-horizontal toward the west-southwest. Near the zone of the isolated Bonin Super Deep Earthquake, which occurred at ~680 km on May 30,2015, the discontinuity is depressed to ~700 km, suggesting a near-vertical penetrating slab and an S-to-P conversion in the coldest slab core, where a large low-temperature anomaly should exist.展开更多
We studied the structure of 12 C through the modified Glauber model using the density distributions calculated by the relativistic mean field theory. The experimental reaction cross sections of 12 C + 12 C were analyz...We studied the structure of 12 C through the modified Glauber model using the density distributions calculated by the relativistic mean field theory. The experimental reaction cross sections of 12 C + 12 C were analyzed within the MOL by a χ 2 -fitting procedure. The effects of the nuclear deformation on the reaction cross sections are studied. The reliable structure of 12 C is deduced. The studies show that the conjunction of these two models will be a more effective tool to study the properties of nuclei.展开更多
Prophenol oxidase isoform A1 was isolated from Drosophila melanogaster （The sequence has been deposited in GenBank data base under accession number AB557586） PHOX-S strain, and its characteristics and activation mec...Prophenol oxidase isoform A1 was isolated from Drosophila melanogaster （The sequence has been deposited in GenBank data base under accession number AB557586） PHOX-S strain, and its characteristics and activation mechanism were determined. The NH2-terminal region of PHOX-S A1 was determined to be comprised of 15 amino acids with the following sequence MTNMKMKMKAMMR. Comparison of an alignment in the known prophenol oxidase protein sequences from Drosophila melanogaster strains showed high homology in the copper-binding sequences at the Cu （A） site of the active center. Limited proteolysis takes place between Arg-50 and Val-51. Therefore, it is concluded that prophenol oxidase PHOX-S protein was evolved at the upstream, but no evolved at the central site in Drosophila melanogaster.展开更多
We study the reaction cross sections （σR） and root-mean-square （RMS） radii of ^8Li and ^8B, the halo-like nuclei, with stable target ^12C, ^27Al and ^9Be within the standard optical-limit Glauber model, using den...We study the reaction cross sections （σR） and root-mean-square （RMS） radii of ^8Li and ^8B, the halo-like nuclei, with stable target ^12C, ^27Al and ^9Be within the standard optical-limit Glauber model, using densities obtained from relativistic mean-field （RMF） formalisms and other types of distributions. It is found that the experimental σR can be reproduced well at high energy. The RMS radius and Ar extracted by RMF- theory and harmonic oscillator distribution are compared. larger than those of SLi. In addition, we analyze in detail the We find that the RMS radius and Ar of SB are relationship between σR and density distribution.展开更多
文摘The Izu-Bonin subduction zone in the Northwest Pacific is an ideal location for understanding mantle dynamics such as cold lithosphere subduction. The slab produces a lateral thermal anomaly, inducing local topographic changes at the boundary of a post-spinel phase transformation, considered to be the origin of the ‘660-km discontinuity.’ In this study, the short-period(1–2 Hz) S-to-P conversion phase S660P was used to obtain the fine-scale structure of the discontinuity. More than 100 earthquakes that occurred from the 1980s to the 2020s and were recorded by high-quality seismic arrays in the United States and Europe were analyzed. A discontinuity in the ambient mantle with an average depth of ~670 km was found beneath the 300–400-km event zone in the northern Bonin region near 33°N. Meanwhile, the ‘660-km discontinuity’ has been pushed upward, away from the slab, possibly because of a hot upwelling mantle plume. In the central part of the subduction zone, the 660-km discontinuity is depressed to an average depth of(690 ± 5) km within the slab at approximately 150 km below the coldest slab core, indicating a(300 ± 100) ℃ cold anomaly estimated using a post-spinel transformation Clapeyron slope of(-2.0 ± 1.0) MPa/K. In southern Bonin near 28°N, the discontinuity was found to be further depressed at an average depth of(695 ± 5) km below the deepest event and with a focal depth of ~550 km. The discontinuity is located where the slab bends abruptly to become sub-horizontal toward the west-southwest. Near the zone of the isolated Bonin Super Deep Earthquake, which occurred at ~680 km on May 30,2015, the discontinuity is depressed to ~700 km, suggesting a near-vertical penetrating slab and an S-to-P conversion in the coldest slab core, where a large low-temperature anomaly should exist.
文摘We studied the structure of 12 C through the modified Glauber model using the density distributions calculated by the relativistic mean field theory. The experimental reaction cross sections of 12 C + 12 C were analyzed within the MOL by a χ 2 -fitting procedure. The effects of the nuclear deformation on the reaction cross sections are studied. The reliable structure of 12 C is deduced. The studies show that the conjunction of these two models will be a more effective tool to study the properties of nuclei.
文摘Prophenol oxidase isoform A1 was isolated from Drosophila melanogaster （The sequence has been deposited in GenBank data base under accession number AB557586） PHOX-S strain, and its characteristics and activation mechanism were determined. The NH2-terminal region of PHOX-S A1 was determined to be comprised of 15 amino acids with the following sequence MTNMKMKMKAMMR. Comparison of an alignment in the known prophenol oxidase protein sequences from Drosophila melanogaster strains showed high homology in the copper-binding sequences at the Cu （A） site of the active center. Limited proteolysis takes place between Arg-50 and Val-51. Therefore, it is concluded that prophenol oxidase PHOX-S protein was evolved at the upstream, but no evolved at the central site in Drosophila melanogaster.
基金Supported by One Hundred Person Project of Chinese Academy of Sciences (26010701)Knowledge Innovation Project of Chinese Academy of Sciences (KJCX2-SW-N13,KJCX3-SYW-N2)National Natural Science Foundation of China (10675156)
文摘We study the reaction cross sections （σR） and root-mean-square （RMS） radii of ^8Li and ^8B, the halo-like nuclei, with stable target ^12C, ^27Al and ^9Be within the standard optical-limit Glauber model, using densities obtained from relativistic mean-field （RMF） formalisms and other types of distributions. It is found that the experimental σR can be reproduced well at high energy. The RMS radius and Ar extracted by RMF- theory and harmonic oscillator distribution are compared. larger than those of SLi. In addition, we analyze in detail the We find that the RMS radius and Ar of SB are relationship between σR and density distribution.
