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121.
本文采用先进的LAGFD风、浪数值模式和POM(PrincetonOceanModel)三维海流模式对自1945~1995年间发生并影响南海东部海域的299个历史最强热带气旋过程进行数值后报,给出了南海东部部分海域(19°~23°N,113°~118°E)中1000m等深线内60个点的多年一遇风、浪、流和水位极值,并简要分析了南海东部(15°~27°N,108°~122°E)的气候特征,为该海域区域性海洋环境研究与工程开发提供了基础参考数据。 相似文献
122.
Zhongjie Zhang Yanghua Wang Yangfan Deng Lin Chen Jing Wu Jiwen Teng Yun Chen Weiming Fan Giuliano Panza 《地学学报》2013,25(3):245-251
The mechanism of the disruption, both lithospheric thinning and oceanization of the commonly accepted long‐term‐stable Archaean craton, is still an open question. The available models, all imply a bottom to top process. With the construction of a 1660‐km‐long transect across the eastern North China Craton (NCC), we demonstrate that both the P‐wave velocity and density in the lowermost crust beneath the central section are significantly higher than in the corresponding parts of the south and north sections on the transect. These features are interpreted as geophysical signature of lower crustal underplating, which supplies sufficiently high gravitational potential energy to trigger lateral flow of the lower crust. This magma underplating‐triggered bilateral lower crust flow may facilitate the lithospheric thinning by means of asthenosphere upwelling and decompression melting, which infill the gap produced by the lower crust flow. The underplating‐triggered lower crustal flow can provide an alternative mechanism to explain the NCC lithosphere disruption, which highlights the crustal feedback to Archaean lithosphere disruption, from top to bottom. 相似文献
123.
INTRODUCTIONATislowKWCys-rich(aboutonethird)metal-bindingprotein,lackofaromaticaminoacidresidues.AThasbeenfoundinkidneysandliversofmanymammals,andalsoininvertebrates,microorganismsandplants.ThepresenceofanAT-likeproteinhasbeenfoundinanumberofaquaticorganisms,includingtheplaice(Overnelletal.,1977),rock-fish(Olafsonetal.,1974),goldfish(Marafant,1976),andcrabandshrimp(Olafsonetal.,1979).AThasbecomethesubjectofgreatInterestinrecentyearsduetotheirwideexistenceandmetalaffinity.Scientistsha… 相似文献
124.
Yuting Zhang Shanshan Song Bin Zhang Yang Zhang Miao Tian Ziyi Wu Huorong Chen Guangmao Ding Renyan Liu Jingli Mu 《海洋学报(英文版)》2023,42(2):134-141
Toxic harmful algal blooms(HABs) can cause deleterious effects in marine organisms, threatening the stability of marine ecosystems. It is well known that different strains, natural populations and growth conditions of the same toxic algal species may lead to different amount of phycotoxin production and the ensuing toxicity. To fully assess the ecological risk of toxic HABs, it is of great importance to investigate the toxic effects of phycotoxins in marine organisms. In this study, the short-te... 相似文献
125.
Journal of Oceanology and Limnology - The Kuroshio Extension (KE) is one of the most eddy-energetic regions in the global ocean. However, most mesoscale eddy studies in the region are focused on... 相似文献
126.
Mackerel(Pneumatophorus japonicus) proteins were hydrolyzed by five proteases:trypsin,papain,neutrase,acid protease,and flavourzyme.The hydrolysate treated by neutrase exhibited the highest antioxidant activity.Response surface methodology(RSM) was employed to optimize the hydrolysis conditions in an effort to obtain a mackerel protein hydrolysate(MPH) with the highest DPPH radical scavenging activity.The MPH was fractioned using a series of ultrafiltration membranes and five fractions,namely,MPH-Ⅰ(10kDa),MPH-Ⅱ(10-2.5 kDa),MPH-Ⅲ(1-2.5 kDa),MPH-Ⅳ(0.4-1 kDa),and MPH-V(below 0.4 kDa),were obtained.DPPH radical scavenging activity,reducing power,hydroxyl radical scavenging activity,and the lipid peroxidation inhibition capability of these fractions were evaluated.The fractions in molecular weights 2.5 kDa(MPH-Ⅲ,MPH-Ⅳ,and MPH-Ⅴ),which occupied 93.4%of the total fractions,showed the strongest antioxidant activity;and the antioxidant activities of the three fractions are similar to each other.Using SP Sephadex C-25 and Sephadex G-25 columns,eight fractions were obtained from the MPH(2.5 kDa).The isolated peptide I(1 664 kDa) displayed the highest DPPH radical scavenging activity.Therefore,MPH is a potential source of antioxidant peptides. 相似文献
127.
128.
为更好地利用FY-3A气象卫星上中分辨率光谱成像仪 (MERSI) 资料高空间分辨率及多光谱的优势,细致分析云系在宏、微观方面的多重特征,首先利用平面平行辐射传输模式 (SBDART) 证明了MERSI的0.65,1.6 μm和11.25 μm通道能够分别反映云光学厚度、云粒子大小、云顶高度的信息,然后采用三通道合成彩色图像的方法,对FY-3A气象卫星云图进行云的分类解释判读。该技术可直观区分有云区、无云区,显示海陆分界,并且使不同云类在云图上体现为不同颜色。同时,FY-3A气象卫星高达1000 m甚至250 m的空间分辨率也使云的细致结构更为清晰,两项优势的叠加,大大提升了云的分类解释判读的准确程度和精细化水平。文中还尝试寻找典型云系的三通道特征值,以期为模糊C均值聚类 (FCM) 方法中聚类中心的选定提供经验值参考。 相似文献
129.
Introduction The tidal variation signals of the solid Earth recorded with the modern measuring techniques can be used to provide effectively the means to cognize the Earths motion, deformation and structure character, especially to monitor the material motion in the Earths interior. In the recent 20 years, the distribution character of the global gravity field has made great progress since the continuous and deep theoretical studies in geophysics and geodesy domains. The successful manufactur… 相似文献
130.