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101.
Ma Jun Song Jinming Li Xuegang Yuan Huamao Li Ning Duan Liqin Wang Qidong 《中国海洋湖沼学报》2020,38(4):1215-1224
An investigation was carried out in the Y3 seamount area of the Western Pacific Ocean in December 2014,and the distribution of dissolved inorganic carbon(DIC) and its relationship with environmental factors in this area were explored.The results show that DIC concentration was higher in the adjacent waters of the Y3 seamount area,and the uplift of DIC isolines at the stations was close to the seamount.Meanwhile,interaction between the North Equatorial Current(NEC) and the Y3 seamount affected the DIC distribution i.e.,the upwelling in the same direction of the NEC was obvious,resulting in a decreasing trend of average concentration of DIC in the 200 m water column from the top to the two side s in this direction but in the cross direction.The DIC concentration increased with the water depth increase,and its distribution was affected by various environmental factors.In the surface water,high temperature was a decisive factor for the decrease of the DIC concentration,but the photosynthesis of phytoplankton showing only a weak influence.In the North Pacific Tropic Water(NPTW),DIC production rate from organic matter decomposition was higher than that of DIC consumption by phytoplankton photosynthesis,leading to a continual increase of DIC.In the North Pacific Intermediate Water(NPIW),organic matter decomposition played a leading role in the increase of DIC.In the deep water,decomposition of organic matter weakened,and the dissolution of CaCO_3 controlled the carbonate system,and DIC had the smallest variation range. 相似文献
102.
Journal of Oceanology and Limnology - Thymidylate synthase (TS) is a key enzyme in the de novo biosynthesis of thymidine monophosphate, serving as a well-known drug target in chemotherapy against... 相似文献
103.
第三次国土调查数据库是第三次国土调查工作的主要成果,是支撑未来自然资源管理各项工作的关键,其质量必须得到充分重视.对数据库进行充分自检并依据自检问题逐一修改,是减少后期工作量、保障第三次国土调查数据库质量的重要手段.本文通过对湖南省第三次国土调查数据库自检内容和方法的分析,梳理了第三次国土调查数据库自检工作存在的不足,... 相似文献
104.
INTR0DUCnONAlloycoatingscandetivelyproteCtsteelagainstcormsioninseri0uscormsionenvir-orunent,suchasthedrinesplashandtidalzones-TwoInainhodiptincaldrinumalloycOaingswidelyusedcommroiallyareGalfancoaing(contalningZn-5wt%kl-us)devel-oPedbytheIntemaionaltalZincReenhheZaionandhocoating(c0n-talningZn-55Wt%Al-1.6Wt%Si)develoPedbytheBethlehemSteelCorpOration-Anewrinc-basedalloycOaingdevel0PedbyNortheaStemUniversityisdiscussedinthesPaperbyelecthehendcalmethod.FromSun(l996),welmOWthecorms… 相似文献
105.
INTRODUCTIONThetoxicityofheavymetalsreleasedintotheenvironmenthasrecentlytriggeredanumberofstudiesaimingattheremovalofmetalionsfromaqueoussolutions (FourestandVolesky ,1 997;FehrmannandPohl,1 993 ;KuyucakandVolesky,1 989) .Itwasfoundthattheaccumulationofheavymeta… 相似文献
106.
?о???????EGM??DTM???????????????????????????????????????EGM2008??SRTM3???????????????????????????????????????????????????Tzz???????????????????μ??????????????????????????????????????????????????????????????????????????????????????λ???????????????仯??????λ???????ж?????????????????????????????????????????? 相似文献
107.
108.
土地登记代理是土地市场中介服务内容的一部分,是土地市场发展的产物。土地登记政策性强,法定程序严密,权利人自己办理,往往因不了解相关政策法规和缺乏经验而大费周折,也给土地登记部门增加了压力和行政成本。再基于土地使用权变更频繁的新形势,土地登记代理应运而生。淄博市与时俱进,勇于创新,积极稳妥地推进土地登记代理工作,促进了土地市场的健康发展。 相似文献
109.
Peng-Xiong Ma Yong-Jie Zhang Ya-Peng Zhang Yao Li Jing-Jing Zang Xiang Li Tie-Kuang Dong Yi-Zhong Fan Shi-Jun Lei Jian Wu Yu-Hong Yu Qiang Yuan Chuan Yue Zhi-Yu Sun 《天文和天体物理学研究(英文版)》2019,(6):63-70
The Plastic Scintillator Detector(PSD) onboard the DArk Matter Particle Explorer(DAMPE)is designed to measure cosmic ray charge(Z) and to act as a veto detector for gamma ray identification.To fully exploit the charge identification potential of PSD and to enhance its capability to identify gamma ray events, we develop an alignment method for the PSD. The path length of a given track in the volume of a PSD bar is derived taking into account the shift and rotation alignment corrections. By examining energy spectra of corner-passing events and fully contained events, position shifts and rotations of all PSD bars are obtained, and are found to be on average about 1 mm and 0.0015 radian respectively. To validate the alignment method, we introduce artificial shifts and rotations of PSD bars into the detector simulation.These shift and rotation parameters can be recovered successfully by the alignment procedure. As a result of the PSD alignment procedure, the charge resolution of the PSD is improved from 4% to 8%, depending on the nuclei. 相似文献
110.
P. Beck E. Quirico A. Garenne Q.‐Z. Yin L. Bonal B. Schmitt G. Montes‐Hernandez G. Montagnac R. Chiriac F. Toche 《Meteoritics & planetary science》2014,49(11):2064-2073
Sutter's Mill is a regolith breccia composed of both heavily altered clasts and more reduced xenoliths. Here, we present a detailed investigation of fragments of SM18 and SM51. We have characterized the water content and the mineralogy by infrared (IR) and thermogravimetric analysis (TGA) and the structure of the organic compounds by Raman spectroscopy, to characterize the secondary history of the clasts, including aqueous alteration and thermal metamorphism. The three methods used in this study suggest that SM18 was significantly heated. The amount of water contained in phyllosilicates derived by TGA is estimated to be approximately 3.2 wt%. This value is quite low compared with other CM chondrites that typically range from 6 to 12 wt%. The infrared transmission spectra of SM18 show that the mineralogy of the sample is dominated by a mixture of phyllosilicate and olivine. SM18 shows an intense peak at 11.2 μm indicative of olivine (Fig. 1). If we compare SM18 with other CM and metamorphosed CM chondrites, it shows one of the most intense olivine signatures, and therefore a lower proportion of phyllosilicate minerals. The Raman results tend to support a short‐duration heating hypothesis. In the ID/IG versus FWHM‐D diagram, SM18 appears to be unusual compared to most CM samples, and close to the metamorphosed CM chondrites Pecora Escarpment (PCA) 91008 and PCA 02012. In the case of SM51, infrared spectroscopy reveals that olivine is less abundant than in SM18 and the 10 μm silicate feature is more similar to that of moderately altered CM chondrites (like Murchison or Queen Alexandra Range [QUE] 97990). Raman spectroscopy does not clearly point to a heating event for SM51 in the ID/IG versus FWHM‐D diagram. However, TGA analysis suggests that SM51 was slightly dehydrated as the amount of water contained in phyllosilicates is approximately 3.7 wt%, which is higher than SM18, but still lower than phyllosilicate water contents in weakly altered CM chondrites. Altogether, these results confirm that fragments with different secondary histories are present within the Sutter's Mill fall. The dehydration that is clearly observed for SM18 is attributed to a short‐duration heating based on the similarity of its Raman spectra to that of PCA 91008. Because of the brecciated nature of Sutter's Mill and the presence of adjacent clasts with different thermal histories, impacts that can efficiently fragment and heat porous materials are the preferred heat source. 相似文献