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71.
A new record of Sebastes koreanus(Kim and Lee,1994) was documented based on morphological characters and DNA barcoding. Fifty-six S ebastes specimens were collected from the coastal waters of northern China. Samples were identified as S. koreanus based on morphological characters. The coloration and morphometric measurements were consistent with those described from specimens collected in South Korea. In this study,specimens had the following morphological characteristics:light brown body with dark stripes and tiny dark spots,4–5 wide indistinct vertical patterns on the side,2 radial stripes behind and below the eyes,1 large dark blotch on the opercle. Additionally,the following meristic characters were recorded:dorsal fin XIV-13,pectoral fin 16,anal fin III-6–7,pelvic fin I-5,lateral line scales 29–30,and vertebrae 26. The fragment of cytochrome oxidase subunit I(C OI) gene of mitochondrial DNA was sequenced for phylogenetic analysis. The mean genetic distance within the species was 0.3%. Net genetic distances between S. koreanus and other S ebastes species ranged from 3.1% to 7.6%,which was greater than the threshold for species delimitation. The phylogenetic analysis strongly supports the validity of S. koreanus in China at the genetic level. The origion,evolution,patterns of speciation and unique features in genome divergence among primate lineages of this species still need future directions of research. 相似文献
72.
Yoshiaki Fujii 《Journal of Atmospheric and Solar》2011,73(5-6):643-652
This study suggests that the cause of the stagnation in global warming in the mid 20th century was the atmospheric nuclear explosions detonated between 1945 and 1980. The estimated GST drop due to fine dust from the actual atmospheric nuclear explosions based on the published simulation results by other researchers (a single column model and Atmosphere-Ocean General Circulation Model) has served to explain the stagnation in global warming. Atmospheric nuclear explosions can be regarded as full-scale in situ tests for nuclear winter. The non-negligible amount of GST drop from the actual atmospheric explosions suggests that nuclear winter is not just a theory but has actually occurred, albeit on a small scale. The accuracy of the simulations of GST by IPCC would also be improved significantly by introducing the influence of fine dust from the actual atmospheric nuclear explosions into their climate models; thus, global warming behavior could be more accurately predicted. 相似文献
73.
D. J. Smith M. G. Petterson A. D. Saunders I. L. Millar G. R. T. Jenkin T. Toba J. Naden J. M. Cook 《Contributions to Mineralogy and Petrology》2009,158(6):785-801
Savo, Solomon Islands, is a historically active volcano dominated by sodic, alkaline lavas, and pyroclastic rocks with up
to 7.5 wt% Na2O, and high Sr, arc-like trace element chemistry. The suite is dominated by mugearites (plagioclase–clinopyroxene–magnetite ± amphibole ± olivine)
and trachytes (plagioclase–amphibole–magnetite ± biotite). The presence of hydrous minerals (amphibole, biotite) indicates
relatively wet magmas. In such melts, plagioclase is relatively unstable relative to iron oxides and ferromagnesian silicates;
it is the latter minerals (particularly hornblende) that dominate cumulate nodules at Savo and drive the chemical differentiation
of the suite, with a limited role for plagioclase. This is potentially occurring in a crustal “hot zone”, with major chemical
differentiation occurring at depth. Batches of magma ascend periodically, where they are subject to decompression, water saturation
and further cooling, resulting in closed-system crystallisation of plagioclase, and ultimately the production of sodic, crystal
and feldspar-rich, high-Sr rocks. The sodic and hydrous nature of the parental magmas is interpreted to be the result of partial
melting of metasomatised mantle, but radiogenic isotope data (Pb, Sr, Nd) cannot uniquely identify the source of the metasomatic
agent. 相似文献
74.
Satoru Yamamoto Ryosuke Nakamura Tsuneo Matsunaga Yoshiko Ogawa Yoshiaki Ishihara Tomokatsu Morota Naru Hirata Makiko Ohtake Takahiro Hiroi Yasuhiro Yokota Junichi Haruyama 《Icarus》2012,218(1):331-344
The distribution and the geological context of the olivine-rich exposures in the South Pole-Aitken (SPA) Basin on the Moon were investigated based on the spectral data obtained from the Spectral Profiler (SP) and Multiband Imager (MI) onboard the Japanese lunar explorer Kaguya/SELENE. The olivine-rich exposures are found only in the peak rings or central peaks of the Schrödinger basin and Zeeman crater, which are located in the outer region of the SPA Basin and not in the center region. On a localized scale, the olivine-rich materials are exposed on landslide features on the crater walls or sloped wall of the central peaks or the peak rings. Another observational finding is the co-existence of olivine-rich and plagioclase-rich materials on a kilometer scale spanning most of the olivine-rich sites in the Schrödinger basin. Pyroxene-rich materials are found in fresh craters outside the peak rings or the central peaks with olivine-rich materials. Based on these results, the following scenario are proposed: (1) the impact to form the SPA Basin melted a large amount of the lunar upper mantle and crust, and distributed the melted materials to the outer region; (2) local differentiation of melted materials hid the olivine-rich materials in the center region of the SPA Basin; (3) later impacts that formed the Schrödinger and Zeeman craters excavated and exposed the olivine-rich materials to the surface again; and (4) space weathering and regolith gardening obscured the olivine-rich spectra at the exposure sites, but recent, small scale impacts or landslides on the sloped wall exposed fresh olivine-rich materials, allowing the identification of the olivine-rich exposures by spectral remote-sensing. This suggests that several, different scale events play an important role in forming the surface distributions of originally deep-seated materials on the Moon, as well as on other planetary bodies. 相似文献
75.
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78.
The interaction between mechanically generated regular waves and wind waves is experimentally investigated in a wind-wave tunnel. It is shown that the growth process of regular waves is divided into the four distinct stages as follows: (1) almost independent coexistence of wind waves and regular waves, (2) attenuation of wind waves with simultaneous growth of regular waves, (3) rapid growth of regular waves after disappearance of wind waves, and (4) transition of regular waves to wind waves after the wave breaking. At the second stage there is an apparent relation between the attenuation of wind waves and the growth of regular waves. This fact suggests that there is some strong nonlinear interactions which transfers energy effectively from wind waves to regular waves. 相似文献
79.
Zooplankton biomass consisting of large and small-size copepods, copepod nauplii and tintinnids were investigated over a period of one year at two stations in Funka Bay, Japan. The food requirement of zooplankton was also estimated using the method of Ikeda and Motoda. Estimated total carbon requirement of zooplankton in the coastal and central parts of the bay was equivalent to 52 and 38% of the annual primary production, respectively. These corresponded to zooplankton production of 12–13 gC·m–2·yr–1.The total carbon requirement at each station increased to 63 and 74% of the primary production during summer compared with 26 and 3% in spring or 19 and 17% in winter. The microzooplankton (copepod nauplii and tintinnids) accounted for about half of the carbon requirement from April to November.Food requirements reached 161% at the coastal station and 194% at the central station of the daily organic carbon production during September. Zooplankton may also feed on carbon sources other than living phytoplankton. This could account for the observed decrease in particulate organic carbon in a water column.Contribution No. 202 from the Research Institute of North Pacific Fisheries, Faculty of Fisheries, Hokkaido University. 相似文献
80.
Vertical fine distributions of suspended matter and some chemical compositions in seawater were measured in the layer near the seabed. Distributions of organic suspended matter were almost uniform throughout the layer, but others were anomalous. However, with respect to their peak heights and distribution patterns, the tendency of profiles was the same on the whole. We suggested that these anomalous distributions were primarily caused by the destruction of the large flocculent particle on the seabed and by upward diffusion of disintegrated particles. The similarity of profiles between chemical compositions of dissolved substances and suspended matter of non-dissolved substances, was explained by assuming that pore water in the large particle was simultaneously transported with disintegrated particles after the destruction. An equation for the vertical distribution of suspended matter near the seabed was derived, provided that the rate of destruction of large flocculent particle was in proportion to the current velocity on the seabed. The equation represented the existence of the anomalous distribution, which was continuously changing its pattern. Measurements of vertical profiles of suspended matter showed almost the same tendency with the theory. From the characteristics of the theoretical equation, it was expected that the eddy diffusivity near the seabed was 1050 cm2/sec. 相似文献