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Distribution,formation and evolution of sand ridges on the East China Sea shelf

Science China Earth Sciences 2010年第1期53卷 101-112页

作者： WU ZiYin JIN XiangLong CAO ZhenYi LI JiaBiao ZHENG YuLong shang jihong Key Laboratory of Submarine Geosciences State Oceanic AdministrationHangzhou 310012China Second Institute of Oceanography State Oceanic AdministrationHangzhou 310012China Department of Earth Sciences Zhejiang UniversityHangzhou 310028China

Based on the integrated results of multiple data types including MBES (Multi-Beam Echo Sounding) and historical topography maps,the LSR (Linear Sand Ridges) on the ECS (East China Sea) shelf are identified,divided into subareas,and *** distribution of sand ridge crests is also *** strikes of the LSR on the ECS shelf fall in a normal distribution with the center point being 155° azimuth with additional peak points at 125°,130°,140°,and 180° *** distribution of the ECS shelf sand ridges is congested in the central area,sparse in the south and north ends,divergent and bifurcated in the eastern area,and densely convergent in the western *** LSR are divided into seven subzones according to the strikes and distribution of the sand ridges;estuary mouth ridges and open shelf sand ridges are identified and marked *** high amplitude change of sea level resulting from the glacial-interglacial cycle is the main cause of the vast development of sand ridges on the ECS *** sediments on the shelf carried by the PYR (Paleo-Yangtze River) are the material source for the LSR formation,and the negative seafloor topography influences the strikes of *** on the effects of LSR distribution,change of sea level,and the simulation of ancient tidal currents,the evolution of the LSR on the ECS shelf is divided into four main stages:Stage Ⅰ before 14.5 ka BP,Stage Ⅱ between 12 and 14 ka BP,Stage Ⅲ from 1.5 to 9.5 ka BP,and Stage Ⅳ after 9 ka BP.

关键词： East China Sea shelf linear sand ridges genetic mechanism evolution of sand ridges multi-beam echo sounding

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Methods and procedures to determine the outer limits of the continental shelf beyond 200 nautical miles

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Acta Oceanologica Sinica 2013年第12期32卷 126-132页

作者： WU Ziyin LI Jiabiao JIN Xianglong FANG Yinxia shang jihong LI Shoujun Key Laboratory of Submarine Geosciences State Oceanic Administration The Second Institute of Oceanography State Oceanic Administration

This paper establishes techniques and methods to determine a variety of boundaries associated with 200 nautical miles beyond the continental shelf. The methods, based on topography, slope and second-deriv- ative profile integrated analysis, are now able to identify automatically the foot of the continental slope （FOS）. By analyzing the sedimentary profile, the points of 1% sediment thickness are recognized. Through the intersection, cut, deletion and mergence calculation of the extrapolated data set of fLxed-point series, the method succeeds in generating automatically the extrapolated boundaries, including the FOS＋60 M line, the 350 M line, and the 2500 m＋100 M line. In addition, based on the automatic analysis of the topographic profile, it can be applied to determine rapidly the points of maximum water depth. Taking the northern Okinawa Trough （OT） as an example, these methods are used to calculate and examine the boundaries in- cluded in the Submission by the People＇s Republic of China Concerning the Outer Limits of the Continental Shelf beyond 200 Nautical miles in Part of the East China Sea （ECS）; the boundaries thus derived have a solid scientific and rational basis.

关键词： 200 nautical miles continental shelf demarcation methodology Okinawa Trough

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A VGGNet-based correction for satellite altimetry-derived gravity anomalies to improve the accuracy of bathymetry to depths of 6500 m

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Acta Oceanologica Sinica 2024年第1期43卷 112-122页

作者： Xiaolun Chen Xiaowen Luo Ziyin Wu Xiaoming Qin jihong shang Huajun Xu Bin Li Mingwei Wang Hongyang Wan Key Laboratory of Submarine Geosciences Second Institute of OceanographyMinistry of Natural ResourcesHangzhou 310012China Ocean College Zhejiang UniversityZhoushan 316021China Key Laboratory of Ocean Space Resources Management Technology Marine Academy of ZhejiangHangzhou 310012China School of Oceanography Shanghai Jiao Tong UniversityShanghai 200240China School of Civil Engineering and Architectures Zhejiang University of Science and TechnologyHangzhou 310023China National Center for Archaeology Beijing 100013China

Understanding the topographic patterns of the seafloor is a very important part of understanding our *** the science involved in bathymetric surveying has advanced much over the decades,less than 20%of the seafloor has been precisely modeled to date,and there is an urgent need to improve the accuracy and reduce the uncertainty of underwater survey *** this study,we introduce a pretrained visual geometry group network(VGGNet)method based on deep *** apply this method,we input gravity anomaly data derived from ship measurements and satellite altimetry into the model and correct the latter,which has a larger spatial coverage,based on the former,which is considered the true value and is more *** obtaining the corrected high-precision gravity model,it is inverted to the corresponding bathymetric model by applying the gravity-depth *** choose four data pairs collected from different environments,i.e.,the Southern Ocean,Pacific Ocean,Atlantic Ocean and Caribbean Sea,to evaluate the topographic correction results of the *** experiments show that the coefficient of determination(R~2)reaches 0.834 among the results of the four experimental groups,signifying a high *** standard deviation and normalized root mean square error are also evaluated,and the accuracy of their performance improved by up to 24.2%compared with similar research done in recent *** evaluation of the R^(2) values at different water depths shows that our model can achieve performance results above 0.90 at certain water depths and can also significantly improve results from mid-water depths when compared to previous ***,the bathymetry corrected by our model is able to show an accuracy improvement level of more than 21%within 1%of the total water depths,which is sufficient to prove that the VGGNet-based method has the ability to perform a gravity-bathymetry correction and achieve outstanding results.

关键词： gravity anomaly bathymetry inversion VGGNet multibeam sonar satellite altimetry

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Effects of Long-term Site-specific Fertilization on Soil Physical and Chemical Properties and Nutrients in Dry Farmland

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Agricultural Science & Technology 2017年第11期18卷 2118-2122页

作者： Xiaojun WANG Yuqing SUN Yong WANG Xiaojuan ZHANG shangpei ZHANG Junxue YANG Shiwu LUO jihong shang Bingwen CHENG Guyuan Branch of Ningxia Academy of Agriculture and Forestry Sciences Guyuan 756000China

In order to investigate the variation in soil physical and chemical properties and nutrients in the mountainous areas in southern Ningxia, and to provide a theoretical basis for fertilization management in local farmland, the soil p H, total salt content,crop root length, root weight, soil organic matter, available nitrogen, total nitrogen, total phosphorous and total potassium in different fertilization treatments were measured from 2010 to 2016. Multiple comparisons of the data were performed using Duncan's new multiple range test. The results indicated that in the 0-20 cm soil layer, soil p H value and total salt content changed in different patterns, and varied greatly from 2010 to 2016(P<0.05). The changes of both root length and root weight of millet over time fitted S-shaped curves. The root length and root weight in the four fertilization treatments(Treatment 2 to Treatment5) increased faster than those in the control(Treatment 1). The soil organic matter content in all the five treatments gradually increased from 2010 to 2016. The content of alkaline hydrolyzable nitrogen in soil rapidly increased in the first two to three years of the experiment, followed by a slow increase or decrease in 2013, and then raised rapidly again from 2014 to *** soil total nitrogen content varied significantly from 2010 to 2016. The total phosphorus content in soil changed in a different pattern from that of total nitrogen content. The seven-year field trails revealed that soil p H, total salt content, root length, root weight and soil nutrient all changed with the increase of fertilizer level, and that long-term fertilization is of significance for maintaining soil fertility, improving soil quality and reducing soil salinization.

关键词： Site-specific fertilization Physical and chemical properties Nutrient Soil quality

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The Influence of Microbial Community on Oil Reservoirs:A Case Study on the Mesozoic Natural Gas in the Pengyang Area,Southwestern Ordos Basin,China

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Acta Geologica Sinica(English Edition) 2025年第1期99卷 144-158页

作者： shang Ting NIU Xiaobing LI Mingrui ZHANG Zhongyi HUANG Xuan HAN Tianyou ZHANG Xiaolei LI jihong CHU Meijuan LIU Xin School of Geography and the Environment Xianyang Normal UniversityXianyang712000China State Key Laboratory of Continental Dynamics Northwest UniversityXi'an 710069China PetroChina Changqing Oilfield Company Xi'an 710018China Exploration&Development Research Institute of PetroChina Changqing Oilfield Company Xi'an 710018China National Engineering Laboratory for Exploration and Development of Low-Permeability Oil&Gas Fields Xi'an 710018China Northwest University Xi’an 710069China

The formation of Mesozoic natural gas in the Pengyang area of southwestern Ordos Basin is discussed,from the perspective of microbial community characteristics,in order to clarify the relationship between the origin of natural gas and its associated indigenous microbial *** types and diversity of indigenous microbial communities associated with the oil reservoir were studied by means of collecting reservoir formation water samples from exploration *** indigenous microbial communities in the Chang 8 member of the Yanchang Formation were primarily distributed within Proteobacteria and Firmicutes,including the specific species and genera of Methylobacter,Pseudomonas,Haibacter,Toxobacillus,Acinetobacter and Adura *** results of diversity analysis shows that the number of common genes was 5448,while the number of unique genes and information was *** reflects the fact that the strata in the study area are relatively closed and not invaded by external water sources,which leads to the development of biological community *** conjunction with the analysis of geochemical characteristics of oil and gas reservoirs in this area,this indicates that the study area possesses the necessary geological conditions for microbial *** is the first time that the species and diversity of the indigenous microbial community in the Ordos Basin have been analyzed,showing that microbial degradation is the main cause of natural gas formation here,changes the characteristics of crude oil in this area and provides first-hand information on the impact of indigenous microorganisms on the reservoir.

关键词： microbial community source of natural gas Yanchang Formation Pengyang area Ordos Basin

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变频调速在氧化铝生产中应用的节能效果

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轻金属 2001年第2期 56-57页

作者：商继红王仰俊山西铝厂山西河津043300

介绍PWM型交流变频工作原理、技术性能、控制特点及其应用情况 ,说明该装置在生产中应用的节能效果。

关键词：变频调速氧化铝生产节能

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Effects of carbon content on the microstructure and tensile properties of a low-density steel

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 391-401页

作者： Yongxuan shang Mingyu Fan Shuyong Jiang Zhongwu Zhang Key Laboratory of Superlight Materials and Surface Technology Ministry of EducationCollege of Materials Science and Chemical EngineeringHarbin Engineering UniversityHarbin 150001China State Key Laboratory of Metal Material for Marine Equipment and Application Iron&Steel Research Institute of Ansteel Group CorporationAnshan 114009China

Carbon can change the phase components of low-density steels and influence the mechanical *** this study,a new method to control the carbon content and avoid the formation ofδ-ferrite by decarburization treatment was *** microstructural changes and mechanical characteristics with carbon content induced by decarburization were systematically ***-Jaoul(C-J)analysis was employed to examine the work hardening characteristics during the tensile *** decarburization by heat treatments,the carbon content within the austenite phase decreased,while Mn and Al were almost unchanged;this made the steel with full austenite transform into the austenite and ferrite dual ***,(Ti,V)C carbides existed in both matrix phase and the mole fraction almost the *** addition,the formation of other carbides *** loss induced a decrease in strength due to the weakening of the carbon solid *** the steel with the single austinite,the deformation mode of austenite was the dislocation planar glide,resulting in the formation of *** the dual-phase steel,the deformation occurred by the dislocation planar glide of austenite first,with the increase in strain,the cross slip of ferrite took place,forming dislocation cells in *** the late stage of deformation,the work hardening of austinite increased rapidly,while that of ferrite increased slightly.

关键词： low-density steels carbon content decarburization strengthening mechanisms work hardening behavior

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基于遗传小波神经网络的海底声学底质识别分类

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海洋学报 2014年第5期36卷 90-97页

作者：熊明宽吴自银李守军尚继宏国家海洋局第二海洋研究所浙江杭州310012 国家海洋局海底科学重点实验室浙江杭州310012

分割海底声纳探测图像,提取单元特征向量进行主成份分析,选取均值、标准差、对比度、相关系数、能量及同质性作为训练特征向量,构建小波神经网络。利用遗传算法优化小波神经网络的初始权值及小波参数,对砂、礁石、泥3种底质类型分别进... 详细信息

分割海底声纳探测图像,提取单元特征向量进行主成份分析,选取均值、标准差、对比度、相关系数、能量及同质性作为训练特征向量,构建小波神经网络。利用遗传算法优化小波神经网络的初始权值及小波参数,对砂、礁石、泥3种底质类型分别进行训练,并得到3种底质的测试精度都在90%以上,优于单独利用小波神经网络进行训练时的测试精度,克服了小波神经网络训练时易陷入局部极小的固有缺陷,表明基于遗传算法的小波神经网络可有效用于海底底质声纳图像的识别和分类。

关键词：遗传小波神经网络底质分类声纳图像遗传算法小波分析

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A PHYB-PIF4-auxin module promotes tomato graft formation in response to elevated ambient temperature

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Horticultural Plant Journal 2025年第1期11卷 227-238页

作者： Xianmin Meng Feng Zhang Wencai Yang Qingmao shang State Key Laboratory of Vegetable Biobreeding Key Laboratory of Horticultural Crop Biology and Germplasm Innovation(Ministry of Agriculture)Institute of Vegetables and FlowersChinese Academy of Agriculture SciencesBeijing 100081China Beijing Key Laboratory of Growth and Developmental Regulation for Protected Vegetable Crops Department of Vegetable ScienceCollege of HorticultureChina Agricultural UniversityBeijing 100193China

Grafting is an effective technique for increasing the resistance of vegetables to biotic and abiotic *** has been widely applied to produce solanaceous and melon *** is an important external factor affecting graft ***,the molecular mechanism by which external ambient temperature affects tomato graft formation remains *** this study,we demonstrated that elevating ambient temperature during grafting to 35℃ for more than 24 h after grafting accelerated vascular *** generated self-or heterografted combinations between phyB1B2 and pif4 loss-of-function mutant and wild-type plants,and were mutants unresponsive to graft formation at elevated ambient *** addition,elevated ambient temperature induced SlPIF4 expression during ***4 directly binds the promoters of auxin biosynthesis genes SlYUCCAs and activates their *** investigation revealed auxin accumulation in the graft junction under elevated ambient *** results illuminate the mechanism by which the PHYB-PIF4-auxin module promotes tomato graft formation in response to elevated ambient temperature.

关键词： Graft formation Tomato Temperature Vascular Auxin

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一种大陆坡脚点自动识别与综合判断方法

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测绘学报 2014年第2期43卷 170-177页

作者：吴自银李家彪阳凡林尚继宏李守军金肖兵国家海洋局第二海洋研究所浙江杭州310012 国家海洋局海底科学重点实验室浙江杭州310012 山东科技大学测绘科学与工程学院山东青岛266590 海岛(礁)测绘技术国家测绘地理信息局重点实验室山东青岛266590

为提升自主能力,更好地维护我国海洋权益,进行了200海里以外大陆架划界的核心界限点——大陆坡脚点(FOS)的自动识别方法与算法研究。提出基于二阶导数极值点和D-P算法的二次简化方法,以及原始剖面和D-P剖面的二次求导方法,并给出数据点... 详细信息

为提升自主能力,更好地维护我国海洋权益,进行了200海里以外大陆架划界的核心界限点——大陆坡脚点(FOS)的自动识别方法与算法研究。提出基于二阶导数极值点和D-P算法的二次简化方法,以及原始剖面和D-P剖面的二次求导方法,并给出数据点坡度、水深和二阶导数,以及曲线凹凸性、连续性和分段性等多重FOS识别方法,通过对地形、坡度、二阶导数及D-P剖面的综合分析,最终实现了FOS的自动识别。进行了该方法的底层初步开发,并采用多波束实测水深数据对其进行了有效性验证。

关键词：大陆坡脚点 D-P算法二次拟合二次求导自动识别

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