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analytical method of Cr stable isotope and its application to water pollution survey

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Chinese science Bulletin 2010年第7期55卷 664-669页

作者： GAO YongJuan 1,2.3,MA Teng 4,5,LING WenLi 1,2.LIU CunFu 4,5 & LI Li 4,5 1Faculty of Earth science,china {2. of Geosciences,Wuhan 430074,china 2.tate key laboratory of Geological Processes and Mineral Resources,china {2. of Geosciences,Wuhan 430074,china 3 Graduate School,china {2. of Geosciences,Wuhan 430074,china 4 Biogeological and Environmental Geology laboratory of ministry of education(china {2. of Geosciences) ,Wuhan 430074,china 5 Sino-Hungary Joint laboratory of Environmental sciences and Health,china {2. of Geosciences,Wuhan 430074,china Faculty of Earth science China University of Geosciences Wuhan 430074 China State key laboratory of Geological Processes and Mineral Resources China University of Geosciences Wuhan 430074 China Graduate School China University of Geosciences Wuhan 430074 China Biogeological and Environmental Geology laboratory of ministry of {2. (china university of Geosciences) Wuhan 430074 China Sino-Hungary Joint laboratory of Environmental sciences and Health China University of Geosciences Wuhan 430074 China

High Cr(VI) concentration is a potential serious risk to environment and ecologic ***,it is essential to effectively monitor Cr contamination in water systems and scientifically evaluate its evolution trend.A new method of in-situ tracer technique by Cr isotopic analysis for quantitatively estimating Cr-contamination and its regional evolution in natural waters as well as a case application are reported in this *** on documented literatures,an experimental procedure for chemical separation and purification of Cr in water samples and its analytical method for Cr isotopic measurement by thermal ionization mass spectrometry(TIMS) are *** samples collected around a chemical factory in Hubei Province were analyzed by this *** samples showδ53Cr values ranging from-1.7‰to 7.3‰and an elevating trend with an increasing in distance from the sampling site to pollution source.A functional correlation following Rayleigh fractionation law was established between sample'sδ53Cr value and its extent of Cr *** study suggests that Cr isotopic analysis is an effective method to reveal the spatial distribution and its evolution trend of Cr contamination in the regional water *** is thus helpful to assessing the self-purifying ability of local water system according to Cr isotopic fractionation.

关键词：铬(VI) 水污染调查稳定同位素应用同位素分析供水系统演变趋势示踪技术

Preparation and properties of ultra-fine TiCN matrix cermets by vacuum microwave sintering

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Rare Metals 2010年第5期29卷 528-532页

作者： ZHANG Hou'an YAN Dike TANG Siwen Institute of Material Preparation and Applied Technology Xiamen University of Technology Xiamen 361024 China College of Electromechanical Engineering Hunan University of Science and Technology Xiangtan 411201 China

Ultra-fine titanium carbonitride （TiCN） matrix materials with a grain size less than 1μm were successfully prepared by vacuum microwave sintering. The milling process for raw TiCN particles and the microstructure and properties of cermets produced with a composition of 15wt.%WC-17wt.%（Co＋Ni）-9wt.%Mo2.-59wt.%***0.3 and sintered by vacuum microwave were analyzed by scanning electron microscopy （SEM） and X-ray diffraction （XRD）. The results show that a ball-to-powder mass ratio of 8：1 and a milling time of 50 h provided appropriate conditions for the production of ultra-fine TiCN solid solution powders. The use of vacuum microwave sintering produced cermets with much finer grain and black core structures and higher relative density and hardness than those produced by vacuum sintering technology.

关键词： cutting tools titanium carbonitride grain size microwave sintering milling hardness

河口水体中痕量稀土元素的共沉淀预富集-电感耦合等离子体质谱法测定研究

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分析测试学报 2005年第1期24卷 12-16页

作者：李云春弓振斌李俊温裕云汪霆厦门大学海洋学系厦门大学海洋环境科学教育部重点实验室福建厦门361005

建立了氢氧化铟共沉淀预富集 -电感耦合等离子体质谱法测定河口水体中痕量稀土元素的方法。实验结果表明 ,在80mg·L -1的In3 +和pH9.5的实验条件下 ,在1.0L水样中添加5.0～2.0.0ng的混合稀土标准溶液 ,均能定量回收 ,回收率在82.2.%～1... 详细信息

建立了氢氧化铟共沉淀预富集 -电感耦合等离子体质谱法测定河口水体中痕量稀土元素的方法。实验结果表明 ,在80mg·L -1的In3 +和pH9.5的实验条件下 ,在1.0L水样中添加5.0～2.0.0ng的混合稀土标准溶液 ,均能定量回收 ,回收率在82.2.%～106.9 %之间。方法的分析流程空白为0.04(Tb)～10.17(La)ng·L -1,检出限在0.17(Yb)～1.46(La)ng·L-1之间 ,精密度 (RSD ,n=3)小于11.7 % 。

关键词：河口水体稀土元素共沉淀预富集电感耦合等离子体质谱

Time-Frequency Synchronization Method for Multi-Point Underwater Acoustic Communication System

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Full-scale measurements of dynamic response of suspension bridge subjected to environmental loads using GPS technology

第二十九届中国控制会议

作者： YUAN Fei,CHEN Shengli,LIN Xizhou,CHENG En key laboratory of Underwater Acoustic Communication and Marine Information technology {2. of education,xiamen university,xiamen 361005,P.R.china

Underwater acoustic communication network is one of the most challenging and complex researches in modern communication *** the paper,we proposed a method which could be used in point-to-point system as synchronization while as simple multi-access method in multi-point *** using the time-frequency synchronization method as the prelusion of communication,the system could be suitable for the multi-point underwater acoustic communication *** showed that it could realize efficient detection in the weak signal conditions,and had high reliability and scalability.

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science china(Technological sciences) 2010年第2期53卷 469-479页

作者： YI TingHua1,2. LI HongNan1 & GU Ming2.1State key laboratory of Coastal and Offshore Engineering, Dalian {2. of Technology, Dalian 11602., china 2.tate key laboratory for Disaster Reduction in Civil Engineering, Tongji {2., Shanghai 2.0092. china 1. State key laboratory of Coastal and Offshore Engineering Dalian University of Technology Dalian 116024 China2. State Key Laboratory for Disaster Reduction in Civil Engineering Tongji University Shanghai 200092 China

Nowadays, there are many larger and taller engineering structures than in the past. These structures are commonly designed to be more flexible. Thus, they are sensitive to severe wind gust and earthquake tremor. For the dynamic response prediction, finite element (FE) modal updating and structural health monitoring, the dynamic characteristics of a structure are becoming increasingly important. The aim of this paper is to show an emerging tool-the real time kinematic (RTK) global positioning system (GPS), which is used to measure and monitor the low-frequency vibration of Dalian BeiDa Bridge, a medium span suspension bridge. The modal analysis is firstly performed on the developed three-dimensional FE model according to the original blue prints of the bridge to provide the analytical frequencies and mode shapes. The field ambient vibration tests using the accelerometers on the bridge deck are conducted just prior to the use of the GPS system in order to validate the FE model. And then, the calibration test is done to assess the dynamic displacement measurement accuracy of the GPS in three orthogonal directions. The GPS signal properties, such as the amplitude, standard deviations (STD), power spectral density (PSD), and probability density functions (PDF), are studied in details. After that, a structural health monitoring system based on the GPS is devised and installed on the bridge to provide real-time measurement of deck movement. The output-only modal parameter identification is carried out by using the Periodogram method to investigate the responses of the bridge. The result shows that the spectral densities of the displacements measured by the GPS correspond well with the results by the FEM analysis and the accelerometer vibration test. It is concluded that the GPS method is reliable and useful to clarify the ambient vibration response behaviors of the flexible structures. The integration of the GPS and accelerometer methods results in a hybrid arrangement tha

关键词： health monitoring global positioning system real-time kinematic suspension bridge modal analysis

0号柴油水溶性成分对僧帽牡蛎脂质过氧化的影响

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水产学报 2005年第2期29卷 150-153页

作者：陈荣魏凤琴王重刚厦门大学环境科学研究中心教育部海洋生态环境开放实验室福建省平潭县白青乡水产技术推广站厦门大学生物学系福建厦门 361005 福建平潭 350400

在实验条件下,将僧帽牡蛎分别置于含有0.5、2.5 mg·L-10号柴油水溶性成分的海水中,在污染后1、4、7、11、15 d采样,15 d后转入清洁海水中进行6 d的恢复实验,采样,观察消化腺和鳃脂质过氧化的程度。结果表明:(1)正常生理条件下消化腺... 详细信息

在实验条件下,将僧帽牡蛎分别置于含有0.5、2.5 mg·L-10号柴油水溶性成分的海水中,在污染后1、4、7、11、15 d采样,15 d后转入清洁海水中进行6 d的恢复实验,采样,观察消化腺和鳃脂质过氧化的程度。结果表明:(1)正常生理条件下消化腺和鳃也有一定程度的脂质过氧化,消化腺显著高于鳃;(2.脂质过氧化的程度随污染时间的延长而增加,并存在一定的剂量-效应关系,可作为监测海洋石油污染的生物标志物;(3)解除污染后,脂质过氧化恢复到对照水平。

关键词： 0号柴油水溶性成分僧帽牡蛎脂质过氧化

The reflection of regular and irregular waves by a partially perforated caisson breakwater on a step bed

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Acta Oceanologica Sinica 2009年第4期28卷 107-117页

作者： LIU Yong LIYucheng TENG Bin XIA Zhisheng key laboratory of Ocean Engineering Ocean {2. of china Qingdao 266100 China State key laboratory of Coastal and Offshore Engineering Dalian University of Technology Dalian 116024 China key laboratory of Water ＆ Water ＆ Sediment {2. and Water Hazard Prevention Changsha 410076 China

This study examines the reflection of regular and irregular waves from a partially perforated caisson breakwater located on a step bed. The step bed is treated as an idealized rubble mound foundation. Based on the linear potential theory, an analytical solution is developed to calculate the reflection coefficient of the structure subjected to regular waves. The matched eigenfunction expansion method is used for the solution. The regular wave method is also extended to irregular waves using a linear transfer function. The calculated results obtained for limiting cases are exactly the same as corresponding results given by the previous researchers. The present predictions also agree well with experimental data in the published literatures. Numerical experiments are conducted to examine the variations of the reflection coefficient versus its main effect factors, and some interesting results are presented.

关键词： partially perforated caisson step irregular waves reflection coefficient

Research of the Multiple Access Protocol for Underwater Acoustic Networks Based on OPNET

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Research of the Multiple Access Protocol for Underwater Acou...

Fabrication of 1D Au@SiO2.Nanoparticle Chains with Lanthanide Complex on Its Backbone

第二十九届中国控制会议

作者： YUAN Fei,WANG Shanhong,LIN Bilan,CHENG En (key laboratory of Underwater Acoustic Communication and Marine Information technology {2. of education,xiamen university,xiamen 361005,P.R.china

The research on MAC protocol is one of the key tasks of the underwater acoustic *** this paper,the author used the simulation tool OPNET to research about the performance of the protocols ALOHA and MACAW in the underwater acoustic network,and compared the network performance in the different traffics,such as,the average delay,the throughput and the *** simulation results showed that the performance of the MACAW protocol was better than the ALOHA protocol in the current underwater networks,and both of them can be used in the low traffic network.

关键词： Underwater Acoustic Network Network Performance OPNET Simulation MAC Protocol

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Fabrication of 1D Au@SiO2 Nanoparticle Chains with Lanthanid...