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Accuracy assessment of global ocean tide models in the South China Sea using satellite altimeter and tide gauge data

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Acta Oceanologica Sinica 2020年第12期39卷 1-10页

作者： Yanguang Fu Yikai Feng Dongxu zhou xinghua zhou Jie Li Qiuhua Tang First Institute of Oceanography Ministry of Natural ResourcesQingdao 266061China College of Geodesy and Geomatics Shandong University of Science and TechnologyQingdao 266590China

In this study,to meet the need for accurate tidal prediction,the accuracy of global ocean tide models was assessed in the South China Sea(0°–26°N,99°–121°E).Seven tide models,namely,DTU10,EOT11 a,FES2014,GOT4.8,HAMTIDE12,OSU12 and TPXO8,were *** accuracy of eight major tidal constituents(i.e.,Q1,O1,P1,K1,N2,M2,S2 and K2)were assessed for the shallow water and coastal areas based on the tidal constants derived from multi-mission satellite altimetry(TOPEX and Jason series)and tide gauge *** root mean square values of each constituent between satellite-derived tidal constants and tide models were found in the range of 0.72–1.90 cm in the deep ocean(depth>200 m)and 1.18–5.63 cm in shallow water area(depth<200 m).Large inter-model discrepancies were noted in the Strait of Malacca and the Taiwan Strait,which could be attributable to the complicated hydrodynamic systems and the paucity of high-quality satellite altimetry *** coastal regions,an accuracy performance was investigated using tidal results from 37 tide gauge *** root sum square values were in the range of 9.35–19.11 cm,with the FES2014 model exhibiting slightly superior performance.

关键词： accuracy assessment tide model satellite altimetry tide gauge South China Sea

Equivalence of Network-Solution and PPP-Solution

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Geo-Spatial Information Science 2006年第2期9卷 99-102页

作者： PENG Lin LIU Yanxiong zhou xinghua WU Yongting the First Oceanography Institute SOA 6 Xianxialing Road High-Tech District Qingdao 266061 China

The technique of precise point positioning (PPP) is gradually becoming a popular method in GPS data-processing. In GPS observation equation, the unknown parameters can be separated into two parts: global parameters and local parameters. The global parameters include orbit, satellite clock and geodynamic parameters. The local parameters are site-occupation-specific, such as position, tropospheric delay, etc. The formulas of local parameters are firstly derived under the network-solution and the PPP-solution conditions respectively. If the weight matrix of global parameters in PPP-solution is small enough, the cofactor matrices of local parameters are the same as that in network-solution. Then, 16 daily solutions are obtained in both PPP mode and network mode. Three sites are selected to compare the solutions. The experimental results demonstrated that the difference between two solutions in coordinates and tropospheric delays are only few millimeters. This level of difference can be neglected so that the solutions from both PPP mode and network mode can be taken as the same in the actual application.

关键词： network-solution precise point positioning equivalence network-solution ~ precise point positioning~ equivalence

Preliminary Study on Broadband Resonance of Shaking Table Based on the Compressibility of Gas

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Journal of Beijing Institute of Technology 2019年第2期28卷 257-264页

作者： xinghua zhou Xiao Sun Kehong Tang Lili Cheng Dingxuan Zhao School of Mechanical Science and Engineering Jilin UniversityChangchun 130025China Institute of Applied Technology Jilin UniversityChangchun 130012China College of Mechanical Engineering Yanshan UniversityQinhuangdao 066004China

In order to improve the performance of the shaking table,a vibration-enhanced shaking table which exploited broadband resonance was *** broadband resonance was realized by an adjustable stiffness mechanism which exploited gas *** from the traditional device,a gas filled cylinder(GFC)was mounted between the shake table and the exciter,and a pressure regulator was designed to regulate the gas pressure of the *** natural frequency of the designed shaking table can be adjusted based on the compressibility of gas during the *** principle of stiffness adjustment was theoretically analyzed and a series of experiments were carried out to investigate the effects of regulating the natural *** experimental results indicate that the amplitude can be twice amplified and the natural frequency can be regulated between 2 0 Hz and 6 0 Hz.

关键词： shaking table gas compressibility hydraulic variable stiffness broadband resonance

Multibeam water column data research in the Taixinan Basin:Implications for the potential occurrence of natural gas hydrate

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Acta Oceanologica Sinica 2019年第5期38卷 129-133页

作者： Yilan Chen Jisheng Ding Haiquan Zhang Qiuhua Tang xinghua zhou Xiaoyu Liu First Institute of Oceanography Ministry of Natural Resources

A multi beam sonar survey is carried out in the continental slope of the Taixinan Basin to obtain submarine topographic and water column data. The data are processed to obtain water column images. Anomalous water column images, displaying plume characteristics, are found in gas hydrate enriched areas in the Taixinan *** indicates the presence of natural gas resources in the Taixinan Basin. The multibeam sonar system is shown to provide an accurate and effective approach for detecting sub-sea gas hydrate.

关键词： multibeam sonar water column image plume flow Taixinan Basin gas hydrate

A Method for the Removal of Ray Refraction Effects in Multibeam Echo Sounder Systems

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Journal of Ocean University of China 2008年第2期7卷 233-236页

作者： DING Jisheng zhou xinghua TANG Qiuhua First Institute of Oceanography SOA Qingdao 266061 P. R. China

To a multibeam echo sounder system (MBES), under water sound refraction plays an important role in depth measure- ment accuracy, and errors in sound velocity profile lead to inaccuracies in the measured depth (especially for outer beams). A method is developed to estimate the sound velocity profile based on the depth measured by vertical beam. Using this depth and other pa- rameters, such as t (sound pulse propagation time), θ (beam inclination angle), etc. We can estimate a simple sound velocity profile with which the depth error has been reduced. This method has been tested with a real dataset acquired in the East China Sea.

关键词： multibeam echo sounder system acoustic ray refraction equivalent sound velocity profile

Synthesis and properties of carbon and yttrium co-doped TiO2 photocatalyst

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Synthesis and properties of carbon and yttrium co-doped TiO2...

Trace element characteristics in the diopsides of peridotite xenoliths: a laser ablation-inductively coupled plasma-mass spectrometry study

2014中国功能材料科技与产业高层论坛

作者： LIU Jianmei zhou xinghua ZHU Zhongqi ZHANG Jin LIU Qingju Yunnan Key Laboratory for Micro/nano Materials &Technology Yunnan University

ISBN: (纸本)9783038353522

TiO photocatalysts doped with different element of C and Y were synthesized by sol-gel process using glucose,yttrium nitrate and tetrabutyl titanate as *** characterized by XRD,XPS,TEM,PL and UV-Vis *** photocatalytic activity of samples was investigated by photocatalytic degradation of methylene-blue(MB)under the irradiation of fluorescent *** results indicate that C ion and Y ion are incorporated into the lattice of TiO,and C doping accelerate phase transition from anatase to rutile phase,but Y doping inhabits the phase *** was also found that both C and Y doping can broaden the absorption spectrum to visible light region and inhibit the recombination of the photo-generated electron and hole *** synergy effect of codoped C and Y ions provides C-Y-TiO sample better photocatalytic activity than that of the single-doped samples and P25 under fluorescent *** photo-catalytic activity of the sample with C,Y co-doped is the best under the irradiation of fluorescent *** is94.23%within 3 hours and significantly higher than that of Degussa P25(44.72%)under the same experimental conditions.

关键词： TiO2 C-Y-doping Sol-gel chemistry photocatalyst

来源： cnki会议评论

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Chinese Science Bulletin 1998年第7期43卷 579-583页

作者： Shaohai Chen xinghua zhou S. Y. O’Reilly W. L. Griffin Guohui Zhang M. Zhang Chinese Acad Sci Inst Geol Lab Lithosphere Tecton Evolut Beijing 100029 Peoples R China Macquarie Univ Sch Earth Sci GEMOC Sydney NSW 2109 Australia

Among the various xenoliths entrained by the Cenozoic Hannuoba basalts, peridotite is the most abundant one. The trace elements of the diopsides from the peridotite xenoliths were analysed by LA-ICP-MS. The overall depletion and some heterogeneity of the continental mantle beneath northern North China Craton were indicated by the characteristics of the trace elements. The ∑REE amount in diopside correlates with the Cr/(Cr+Al) ratio of diopside which is indicative of xenolith’s partial melting degree. As the peridotite hosts and pyroxenite veins show similar REE distribution patterns, the composite xenoliths are probably formed by mantle deformation, rather than by the late metasomatism of mantle fluids/melts.

关键词： LA-ICP-MS diopside trace elements.

Therapeutic efficacy of novel memantine nitrate MN-08 in animal models of Alzheimer′s disease and vascular dementia

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中国药理学与毒理学杂志 2023年第7期37卷 492-493页

作者： LIANG Miao zhou xinghua WANG Yuqiang HOI Mag-gie PM ZHANG Zaijun Institute of New Drug Research College of Pharmacy Jinan University State Key Laboratory of Quality Research in Chinese Medicine and Institute of Chinese Medical Sciences University of Macau

OBJECTIVE Alzheimer′s disease (AD)and vascular dementia (VD)are the primary causes of dementia in elderly individuals,and therapeutic options for both conditions are *** of N-methylD-aspartate (NMDA) receptors,decreased cerebral blood flow,and subsequent pathological events,play significant roles in the progression of AD and *** In this study,we investigated the therapeutic effects and underlying mechanisms of MN-08,a novel memantine nitrate,in mouse models of AD and rats with *** MN-08 was found to inhibit Aβ accumulation,prevent neuronal and dendritic spine loss,and attenuate cognitive deficits in 2-month-old APP/PS1 transgenic mice (following a 6-month preventative course) and in 8-month-old triple-transgenic (3×Tg-AD) mice (following a4-month therapeutic course),as well as in rat models of VD with preventive and therapeutic *** vitro,MN-08 was shown to bind to and antagonize NMDA receptors,inhibit calcium influx,and reverse dysregulations of the ERK and PI3K/Akt/GSK3β pathway,subsequently preventing glutamate-induced neuronal ***,MN-08 exhibited favorable pharmacokinetics,blood-brain barrier penetration,and safety profiles in rats and beagle *** These findings suggest that the novel memantine nitrate MN-08 may be a useful therapeutic agent for AD and VD.

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海洋垂直基准研究进展与展望

测绘学报 2017年第10期46卷 1770-1777页

作者：周兴华付延光许军山东科技大学测绘科学与工程学院山东青岛266510 国家海洋局第一海洋研究所山东青岛266061 大连舰艇学院海洋测绘系辽宁大连116018

海洋垂直基准的构建是海洋测绘的基础性工作。2009—2012年,我国初步构建了中国近岸80海里范围内高程/深度基准转换与统一模型。近年来,这一模型扩展到了我国南海、西太平洋和东印度洋,接下来将逐步构建南北极和全球的无缝垂直基准面模... 详细信息

海洋垂直基准的构建是海洋测绘的基础性工作。2009—2012年,我国初步构建了中国近岸80海里范围内高程/深度基准转换与统一模型。近年来,这一模型扩展到了我国南海、西太平洋和东印度洋,接下来将逐步构建南北极和全球的无缝垂直基准面模型,这对推动我国数字海洋建设具有基础的支撑作用。本文主要论述和梳理目前国内外主要沿海国家进行海洋垂直基准构建的研究现状,分析了海洋垂直基准构建的主要工作、途径及关键技术,重点阐述了我国在海洋垂直基准建设实践中取得的成果和存在的问题。

关键词：海洋潮汐垂直基准深度基准面卫星测高调和分析