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Turbidite and bottom-current evolution revealed by anisotropy of magnetic susceptibility of redox sediments in the Ulleung Basin,Sea of Japan

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Chinese Science Bulletin 2012年第6期57卷 660-672页

作者： GE ShuLan SHI XueFa LIU YanGuang WANG KunShan ZOU JianJun DIAO JingYu ZHU ZhiWei WANG ChunJuan First Institute of oceanography State Oceanic AdministrationQingdao 266061China Affiliated Middle school of china ocean university Qingdao 266003China

Anisotropy of magnetic susceptibility(AMS) from above and below 7.31 m in a core from the southern Ulleung Basin shows clear differences on an equal area projection of the lower *** concentrated steep inclination of K 3 and horizontal inclination of K 1 and K 2(K1 ≥K2 ≥K3) are located within the upper part,and the latter two axes lie perpendicular to each other near the bedding *** contrast,random distribution of the three axes and extremely high value of shape parameters(Q=(K1-K2)/[(K1+K2)/2-K3]) are evident in the lower part,indicating complete destruction of the original sedimentary *** result is consistent with data from X-radiographs,which show numerous conglomerates,distortions and cleavages in the lower *** to age models by Liu et al.(2010) and Zou et al.(2010),the bottom age at 7.31 m is 48 cal ka BP,and the time domain is discussed *** degree of AMS(P) is low,1-1.08,and linearly related to the foliation(F)(R2 =0.95,N=176).The relationship between F and linearity(L) implies oblate aligning patterns that are typically sedimentary in *** least five redox couplets were found with the aid of S ratios and other rock magnetic parameters,and in most cases,the original signals of climate survived early *** paleomagnetically reoriented AMS show corresponding changes with millennial events in the last 48 cal *** tilted K 3 directions and reduction of P and F occurred within DO1-BA warm events,when melt water pulse 1A nd the YD cold event took *** turbulent conditions therein,synchronous with coarsening of sediments,provide evidence of strong bottom currents and possible directional changes,as evidenced by different K3 tilting directions.A NE current direction in the last 4.5 cal ka is consistent with in situ measurements of bottom *** of AMS,mainly to climatic modulation,show on the one hand,the limited influence of diagenesis on rock magnetic signals and,on the other hand,the

关键词：磁化率各向异性电流方向氧化还原沉积物底部盆地日本海早期成岩作用

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Impact of the Western Pacific Tropical Easterly Jet on Tropical Cyclone Genesis Frequency over the Western North Pacific

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Advances in Atmospheric Sciences 2022年第2期39卷 235-248页

作者： Ruifen ZHAN Yuqing WANG Yihui DING Department of Atmospheric and ocean Sciences Institute of Atmospheric SciencesFudan UniversityShanghai 200438China Shanghai Typhoon Institute of china Meteorological administration Shanghai 200030China Innovation Center of ocean and Atmosphere System Zhuhai Fudan Innovation Research InstituteZhuhai 519055China international Pacific Research Center and Department of Atmospheric Sciences School of Ocean and Earth Science and TechnologyUniversity of Hawaii at ManoaHonoluluHawaiiHI 96822USA National Climate Center and Laboratory for Climate Studies China Meteorological AdministrationBeijing 100081China

Although it is well known that the tropical easterly jet(TEJ)has a significant impact on summer weather and climate over India and Africa,whether the TEJ exerts an important impact on tropical cyclone(TC)activity over the western North Pacific(WNP)remains *** this study,we examined the impact of the TEJ on the interannual variability of TC genesis frequency over the WNP in the TC season(June-September)during *** results show a significant positive correlation between TC genesis frequency over the WNP and the jet intensity in the entrance region of the TEJ over the tropical western Pacific(in brief WP_TEJ),with a correlation coefficient as high as *** intensified WP_TEJ results in strong ageostrophic northerly winds in the entrance region and thus upper-level divergence to the north of the jet axis over the main TC genesis region in the *** would lead to an increase in upward motion in the troposphere with enhanced low-level convergence,which are the most important factors to the increases in low-level vorticity,mid-level humidity and low-level eddy kinetic energy,and the decreases in sea level pressure and vertical wind shear in the *** these changes are favorable for TC genesis over the WNP and vice *** analyses indicate that the interannual variability of the WP_TEJ intensity is likely to be linked to the local diabatic heating over the Indian ocean-western Pacific and the central Pacific El Ni?o-Southern Oscillation.

关键词： tropical cyclones genesis frequency tropical easterly jet western North Pacific

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Influence of light availability on the specific density,size and sinking loss of Anabaena flos-aquae and Scenedesmus obliquus

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Journal of oceanology and Limnology 2018年第4期36卷 1053-1062页

作者： HUANG Yingylng ZHANG Haichun GAO Rufeng HUANG Xiaochen YU Xiaojuan CHEN Xuechu Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration School of Ecological and Environmental Sciences East China Normal University Shanghai 200241 China Shanghai Environmental Monitoring Center Shanghai 200235 China Shanghai administration Center for ocean affairs Shanghai 200050 China East Sea Information Center of State oceanic administration People's Republic of china Shanghai 200137 China school of Environmental Science and Engineering Shanghai Jiao Tong University Shanghai 200240 China

Harmful algal blooms in eutrophic waters pose a serious threat to freshwater ecosystems and human health. In-situ light availability control is one of the most commonly used technologies to suppress algae in lakes and reservoirs. To develop a better understanding of the effects of light on algal growth, specific density, colony size and sinking loss, Anabaena flos-aquae(cyanobacteria) and Scenedesmus obliquus(green algae) were evaluated in varying light scenarios. The results showed that the specific density and colony size of these two species varied during growth, and there were obvious differences among the light scenarios. At the end of exponential phase, S. obliquus incubated under light-limited condition maintained a higher specific density and formed larger aggregates, whereas A. flos-aquae formed a longer filament length. Both species exhibited higher sinking loss rates with lower light availability. These results implied that the sinking loss rate was not always constant but should be considered as a variable response to the change of light availability, and in-situ light availability control might result in a significant increase of the sinking loss of algae due to the change of size and specific density, thereby further affecting the algal biomass in the water column.

关键词： specific density size light availability control sinking loss

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Oil spill detection by a support vector machine based on polarization decomposition characteristics

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Acta oceanologica Sinica 2016年第9期35卷 86-90页

作者： ZOU Yarong SHI Lijian ZHANG Shengli LIANG Chao ZENG Tao National Satellite ocean Application Service State Oceanic Adminstration Key Laboratory for Space ocean Remote Sensing and Application State Oceanic Administration school of English Language Literature and CultureBeijing International Studies University

Marine oil spills have caused major threats to marine environment over the past few *** early detection of the oil spill is of great significance for the prevention and control of marine *** present,remote sensing is one of the major approaches for monitoring the oil *** polarization synthetic aperture radarc SAR data are employed to extract polarization decomposition parameters including entropy（H） and reflection entropy（A）.The characteristic spectrum of the entropy and reflection entropy combination has analyzed and the polarization characteristic spectrum of the oil spill has developed to support remote sensing of the oil *** findings show that the information extracted from（1-A）×（1-H） and（1-H）×A parameters is relatively evident *** results of extraction of the oil spill information based on H×A parameter are relatively not *** combination of the two has something to do with H and A *** general,when H〉0.7,A value is relatively ***,the extraction of the oil spill information using（1-A）×（1-H） and（1-H）×A parameters obtains evident *** combined parameter is adopted,oil well data would cause certain false alarm to the extraction of the oil spill *** particular the false alarm of the extracted oil spill information based on（1-A）×（1-H） is relatively high,while the false alarm based on（1-A）×H and（1-H）×A parameters is relatively small,but an image noise is relatively *** oil spill detection employing polarization characteristic spectrum support vector machine can effectively identify the oil spill information with more accuracy than that of the detection method based on single polarization feature.

关键词： oil spill polarization synthetic aperture radar characteristic spectrum entropy reflection entropy support vector machine

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Effects of light quality on growth rates and pigments of Chaetoceros gracilis(Bacillariophyceae)

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Journal of oceanology and Limnology 2020年第3期38卷 795-801页

作者： LI Yongfu LI Ruiqian YI Xiaoyan Key Laboratory of Experimental Marine Biology Institute of OceanologyCenter for Ocean Mega-ScienceChinese Academy of SciencesQingdao 266071China Laboratory for Marine Biology and Biotechnology Qingdao National Laboratory for Marine Science and TechnologyQingdao 266237China Nantong Research and Development Center of Marine Science and Technology Institute of OceanologyChinese Academy of SciencesNantong 226019China school of international Aff airs and public administration Ocean University of ChinaQingdao 266100China Xishuangbanna Tropical Botanical Garden Chinese Academy of SciencesMengla 666303China

Light is an important parameter in algal *** this work,the effects of different light qualities on growth of the marine diatom Chaetoceros gracilis are *** cells were cultured under light quantum flux density of 60μmol photons/(m2·s)with nine light qualities:LED red light(LR),LED blue light(LB),LED red plus LED blue light(LR+LB),LED white light(LW),fluorescent white light(FW),and combinations of LW and FW lights with increased proportions of red or blue light(FW+LR,FW+LB,LW+LR,and LW+LB).Blue light promoted the growth of *** *** light qualities,FW+LR,LW+LR,and LR,resulted in the lowest growth *** chlorophyll and carotenoids reached the highest level under LB and the lowest level under LR among monochromatic light sources;however,increasing of the proportion of blue or red light in the white light induced an increase of the chlorophyll and carotenoid *** absorption ability of microalgae was critical for the growth of these organisms,as we observed a positive correlation between the extinction coefficient at different wavelengths and the specific growth *** findings are of importance to improve the culturing of this alga in bioreactors.

关键词： Chaetoceros gracilis light quality pigments wavelength effect mean extinction coefficients

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Mechanisms of carbon storage and the coupled carbon, nitrogen and sulfur cycles in regional seas in response to global change

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Science china Earth Sciences 2017年第5期60卷 1010-1014页

作者： XIE ShuCheng CHEN JianFang WANG FengPing XUN LuYing TANG Kai ZHAI WeiDong LIU JiHua MA WenTao State Key Laboratory of Biogeology and Environmental Geology China University of Geosciences The Second Institute of oceanography State Marine Administration of China Faculty of Life Science and Technology Shanghai Jiaotong University Institute of oceanography Shangdong University College of ocean and Earth Sciences Xiamen University school of ocean and Earth Science Tongji University

*** challenges in scientific frontiers of marine carbon storage in the scenario of global change The marine carbon cycle is influenced by anthropogenic activities,affecting global climate change and casting a significant impact on ***,the complex spatiotemporal process of the marine carbon cycle results in the uncertainty in the estimation of marine carbon budget。

关键词： sulfur anthropogenic cycle scenario affecting microbial warming nutrients anaerobic Bohai

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Numerical Investigations on the Transient Behavior of Sand Waves in Beibu Gulf Under Normal and Extreme Sea Conditions

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china ocean Engineering 2023年第2期37卷 232-246页

作者： ZANG Zhi-peng XIE Bo-tao CHENG Liang HE Fang ZOU Xing State Key Laboratory of Hydraulic Engineering Simulation and Safety Tianjin UniversityTianjin 300072China Key Laboratory of Earthquake Engineering Simulation and Seismic Resilience of china Earthquake administration Tianjin UniversityTianjin 300350China CNOOC Research Institute Co. Ltd.Beijing 100028China school of Marine Science and Engineering Guangzhou International CampusSouth China University of Technology ocean College Zhejiang UniversityZhoushan 316021China

In this study, a morphodynamic numerical model is established with the Regional ocean Modeling System(ROMS)to investigate the transient behavior of sand waves under realistic sea conditions. The simulation of sand wave evolution comprises two steps: 1) a regional-scale model is configured first to simulate the ocean hydrodynamics, i.e., tides and tidal currents, and 2) the transient behavior of sand waves is simulated in a small computational domain under the time-variant currents extracted from the large model. The evolution of sand waves on the continental shelf in the Beibu Gulf is specifically investigated. The numerical results of the two-year evolution of sand waves under normal sea conditions compare well with the field survey data. The transient behavior of sand waves in individual months shows that the sand waves are more stable in April and October than that in other months, which can be selected as the windows for seabed operations. The effects of sediment properties, including settling velocity, critical shear stress and surface erosion rate, on sand wave evolution are also analyzed. Then, the typhoon-induced currents are further superimposed on the tidal currents as the extreme weather conditions. Sand waves with the average wavelength generally have more active behavior than smaller or larger sand waves. The characteristics of the evolution of sand waves in an individual typhoon process are quite different for different hydrodynamic combinations. For the storm conditions, i.e., the real combination and maximum combination cases, the sand waves experience a significant migration together with a damping in height due to the dominant suspended sediment transport. For the mild conditions, i.e., the pure tidal current and minimum combination cases, the sand waves migrate less, but the heights continue growing due to the dominant bedload transport.

关键词： sand waves morphodynamic numerical model normal sea condition extreme sea conditions transient behaviors

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Analysis of internal tidal characteristics in the layer above 450 m from acoustic Doppler current profiler observations in the Luzon Strait

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Science china Earth Sciences 2011年第7期54卷 1078-1094页

作者： LIAO GuangHong YUAN YaoChu Kaneko ARATA YANG ChengHao CHEN Hong Taniguchi NAOKAZU Gohda NORIAKI College of Information Science and Technology Ocean University of China Qingdao 266100 China State Key Laboratory of Satellite ocean Environment Dynamics Second Institute of Oceanography State Oceanic Administration Hangzhou 310012 China Graduate school of Engineering Hiroshima University Higashi-Hiroshima 739-8527 Japan

The characteristics of internal tides in the upper layer of the Luzon Strait are investigated on the basis of direct-observation current data recorded on April 25 and September 26, 2008 by an acoustic Doppler current profiler. Spectral analysis and energy estimation show that the diurnals and semidiurnals carry most of the energy of internal tides. Values of the depth-integrated total energy E for the three frequency bands of diurnal, semidiurnal, and high frequencies are 31, 6.9, and 3.4 kJ. m, respectively. Near-inertial peaks are only present in the baroclinic component. The behavior of typical tidal frequencies （i.e., O1, K1, M2, MK3, and M4） and the near-inertial frequency is basically consistent with linear internal wave theory, which predicts E＋（ω）/E_（ω）=（ω-f）2/（ω＋f）2 at depths above 66 m, while not all prominent tidal components coincide well with the relation of the linear internal wave field at other depths. Examinations of depth structures of the baroclinic tides and temporal variations show that the surface tides and internal tides are both of mixed type, having diurnal inequality and spring-neap fortnight periods. The K1 and O1 tides have comparable cross- and along-shelf components, while the M2 and S2 tides propagate toward the shelf in the northern South china Sea as wave beams. The amplitude and phase of internal tides vary with time, but M2 and S2 tides appear to have structures dominated by the first mode, while the K1 and O1 tides resemble second-mode structures. The minor to major axis ratios are close to expected values of flω in the thermocline.

关键词： current observation acoustic Doppler current prof'fler internal tides internal waves Luzon Strait

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Strategic Communications of the Muslim Brotherhood in Egypt

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Asian Journal of Middle Eastern and Islamic Studies 2019年第1期13卷 93-109,I0007页

作者： Zhaohui Yu Yaohong Liu school of international Relations and public affairs Shanghai International Studies UniversityShanghaiChina

As the oldest and largest religious political organization and a political opposition,the Muslim Brotherhood has long been active in the Egyptian political *** eruption of the‘January 25th Revolution’in 2011 enabled the Muslim Brotherhood to successfully move from behind the scenes to the stage,and the Freedom and Justice Party under the Muslim Brotherhood was highlighted in Egyptian politics and succeed in the administration of the Egyptian *** successful development model of the Muslim Brotherhood is closely related to its strategic communication *** article explores the various strategic communication tactics of the Muslim Brotherhood targeting the internal public,the international community and the stakeholders,including vertical word-of-mouth strategic communications,joint organization strategic communications and social media strategic *** the‘January 25th Revolution’,the Muslim Brotherhood began to adjust to the previous strategic communications,focusing on accelerating the Islamization of the Egyptian legal system,government departments and official media,and new strategic communications have trapped it into a difficult position and it has been faced with more hurdles.

关键词： Muslim brotherhood Strategic communication Egyptian studies the‘January 25th Revolution’

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The inter-annual variability of the Yellow Sea Warm Current surface axis and its influencing factors

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Chinese Journal of oceanology and Limnology 2009年第3期27卷 607-613页

作者：宋德海鲍献文王小华徐玲玲林霄沛吴德星 College of Physical and Environmental oceanography Ocean University of China school of Physical Environmental and Mathematical Sciences University of New South Wales at Australian Defence Force Academy Shandong Maritime Safety administration

Based on the Pathfinder sea surface temperature(PFSST),the surface axis and its pattern of the Yellow Sea Warm Current(YSWC) are discussed.A structure of double-warm-tongue is found in February and it varies in different *** indexes are calculated to represent the westward shift(WSI) and northward extension(NEI) of the warm water in the Yellow Sea(YS).Wavelet analysis illustrates that the WSI and NEI have prominent periods of 3-6 years and 3-4 years,*** Empirical Orthogonal Function(EOF) decomposition is applied to the winter wind stress curl and the Kuroshio Current(KC) transport,which are believed to play important roles in forcing the variability of the YSWC surface *** shows that the WSI is significantly related with the second EOF mode of the wind stress curl in February,which may force the YSWC surface axis moving westward and maintaining the double warm tongues because of its opposite curl in the YSWC *** first EOF mode of wind stress curl in January is propitious for inducing the warm tongue in the YS to advance more ***,the wind stress curls both in January and in February could force variations of the YSWC surface axis;however,the effect of the January wind stress curl is relatively weaker than that of the *** relationship between the NEI and the KC transport is remarkable,and it seems that the stronger KC supplies more power to push the YSWC northward against the southward wind.

关键词： Yellow Sea Yellow Sea Warm Current (YSWC) surface axis inter-annual variability sea surface temperature (SST)

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