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Study on 3D simulation of wave fields in acoustic reflection image logging

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Science china Earth sciences 2008年第S2期51卷 186-194页

作者： TAO Guo,HE FengJiang,WANG Bing,WANG Hua & CHEN Ping State key laboratory of Petroleum Resources and Prospecting,china university of Petroleum,Beijing 102249,china china Univ Petr State Key Lab Petr Resources & Prospecting Beijing 102249 Peoples R China

The borehole acoustic reflection imaging logging is a newly developed acoustic logging method that has attracted many interests. These converted and reflected waves for imaging are usually mixed up with borehole guided waves and therefore difficult to be clearly identified. To improve the downhole tool design and develop more sophisticate data processing and interpretation algorithms,studies on precisely numerical modeling of the wave fields in the acoustic reflection imaging logging are neces-sary and critical. This paper developed a parallelized scheme of 3D finite difference (3DFD) with non-uniform staggered grid and PML absorbing boundary to simulate the acoustic wave fields in isotropic and anisotropic formations. Applications of this scheme to the typical cases of isotropic and anisot-ropic formations and comparison with the results from published analytical solutions have demon-strated the validation and efficiency of the scheme. Higher accuracy and lower computation cost (3.5 times faster than the conventional schemes) have been achieved with this scheme for modeling such a complex wave fields of 60 dB dynamic range with higher frequency (10 kHz). This simulating program provides a quantitative analytical means for studying acoustic reflection imaging tool and development of the data processing and interpretation methods.

关键词： acoustic reflection imaging 3D wave field modeling non-uniform staggered grid PML absorb ring boundary parallel scheme

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

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

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

第三十五届国际光谱会议

作者： J.P.Lai L.M.Yu Y.B.Zhao~* Department of Chemistry and the key laboratory of analytical sciences of the Ministry of Education,College of Chemistry and Chemical Engineering,xiamen university,xiamen 361.05,china

Au nanoparticles coated with silica were successfully fabricated into 1D nanochains with a bi-functional groups compound,2,6-dicarboxylicpydine(DCP).The spherical Au nanoparticles were initially prepared by citrate reduction method with a diameter about 18 nm and then coated by a 4 nm silica shell with amino functionalized *** Au@SiO nanoparticles were interconnected in to chains with DCP by forming amide

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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 university of Technology, Dalian 116024, china 2State key laboratory for Disaster Reduction in Civil Engineering, Tongji university, Shanghai 200092, 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

Fluorescent Core-shell Silica Nanoparticles as Functionable Precursors:Towards Multicolor and Multifunctional Nanoprobes

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Fluorescent Core-shell Silica Nanoparticles as Functionable ...

Hydrogen isotopic characteristics and their genetic relationships for individual n-alkanes in plants and sediments from Zoigê marsh sedimentary environment

第三十五届国际光谱会议

作者： C.L.Wu J.Q.Hong X.Q.Guo Y.B.Zhao~* Department of Chemistry and the key laboratory of analytical sciences of the Ministry of Education College of Chemistry and Chemical Engineering xiamen university xiamen 361.05 china

＜正＞Rational design of functional nanoparticles has attracted a great deal of attention in multiplex bioanalysis and multifunctional ***,we have proposed a post-encoding concept[1]to the design and preparation of encoding fluorescent probes, which makes the preparation process of multicolor fluorescent spheres rather laborsaving

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Science china Earth sciences 2010年第9期53卷 1329-1334页

作者： DUAN Yi1, ZHENG ChaoYang2 & WU BaoXiang1 1 key laboratory of Petroleum Resources Research, Institute of Geology and Geophysics, Chinese Academy of sciences, Lanzhou 730000, china 2 Department of Geology, Northwest university, Xi’an 710069, china 1. key laboratory of Petroleum Resources Research Institute of Geology and Geophysics Chinese Academy of Sciences Lanzhou 730000 China2. Department of Geology Northwest University Xi’an 710069 China

To understand internal relations of their hydrogen isotopic compositions in typical marsh environment, we, using GC-IRMS analytical technique, measured the hydrogen isotopes of individual n-alkanes in the herbaceous plant, woody plant leaf, and sediments from Zoigê marsh in china. The results show significant differences in the hydrogen isotopic compositions of n-alkanes among the different kinds of plants and the different species in the same kind. δD values of n-alkanes in the herbaceous plants (from -254‰ to -184‰) are lighter than those in woody plant leaf ( from -195‰ to -142‰ ), and the hydrogen isotopic compositions of n-alkanes in K. tibetica P. are lighter than P. pratensis L. The mean δD values of n-alkanes in the sediments from Zoigê marsh reflect that they were derived from herbaceous plants, which is consistent with the peat samples being composed mainly of herbaceous plant remnants. The significant differences in hydrogen isotopic compositions of n-alkanes among the sedimentary samples are caused possibly by environment factors and the difference in input quantity of different herbaceous plants. A certain negative correlation exists between the δ13C and δD values of n-alkanes in the samples, and plant types can be distinguished using the cross plot of δD vs. δ13C values of n-alkanes in the plants. These data and recognitions provide scientific basis for hydrogen isotopic applied research of individual n-alkanes.

关键词： marsh environment plants sediments individual lipids hydrogen isotopes genetic relationship

Distribution of lanthanum among the chloroplast subcomponents of spinach and its biological effects on photosynthesis:location of the lanthanum binding sites in photosystem II

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Science Bulletin 2005年第16期 44-50页

作者： YAN Wenwu, YANG Limin & WANG Qiuquan Department of Chemistry & the MOE key laboratory of Modern Ana-lytical sciences, College of Chemistry and Chemical Engineering, Xia-men university, xiamen 361006, china

The effects of lanthanum at different concen-trations on the related photosynthetic activities of Hill reac-tion, Mg2+-ATPase and Ca2+-ATPase in spinach chloroplast were studied. Experimental results showed that lanthanum can increase all the activities at suitable concentration (15-30 mg·L-1), however, it behaves toxically on them when over used (60 mg·L-1). To get an improved understanding of the mechanism of lanthanum effects on the photosynthesis of spinach, the different subcomponents in the chloroplast of the cultured spinach were isolated, and the content of lan-thanum in each subcomponent was determined by ICP-MS. The results obtained indicated that among these different subcomponents, about 90% out of the total chloroplast lan-thanum was located in photosystem II (PS II) while there was little lanthanum in photosystem I (PS I). Moreover, size ex-clusion high performance liquid chromatography (SE-HPLC) coupled with online UV and ICP-MS detections was novelly used for locating lanthanum binding sites in PS II proteins for the first time. It was found that lanthanum has two bind-ing sites in PS II: La associates with chlorophyll together with magnesium in PS II by partly replacing magnesium and also shares the common binding sites of PS II proteins to-gether with the inorganic cofactors of calcium and manga-nese, influencing the process of photosynthesis.

关键词： lanthanum photosynthesis chloroplast PS II.

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事件诱发电位信号分类的时空特征提取方法

生物化学与生物物理进展 2011年第9期38卷 866-871页

作者：黄志华李明泓马原野周昌乐厦门大学智能科学与技术系厦门361005 厦门大学福建省仿脑智能系统重点实验室厦门361005 福州大学数学与计算机科学学院福州350108 昆明医学院基础医学院昆明650031 中国科学院昆明动物研究所昆明650223

准确对事件诱发电位(ERPs)进行分类,对于各种人类认知研究和临床医学评估非常有意义.由于ERPs信号是非常高维的数据,而且其中包含非常多的与分类无关的信息,从ERPs信号中提取特征尤显重要.分析了共空间模式(CSP)的原理和不足,引入自回归... 详细信息

准确对事件诱发电位(ERPs)进行分类,对于各种人类认知研究和临床医学评估非常有意义.由于ERPs信号是非常高维的数据,而且其中包含非常多的与分类无关的信息,从ERPs信号中提取特征尤显重要.分析了共空间模式(CSP)的原理和不足,引入自回归(AR)模型与白化变换相结合,提出了针对ERPs分类的时空特征提取方法,并设计了验证该方法的认知实验,在认知实验数据上分别用时空特征提取方法与CSP提取特征,用同样的分类器支持向量机(SVM)训练分类器,比较它们的分类效果.实验表明,在ERPs分类问题上,时空特征提取方法与CSP相比具有明显的优势,在参数确定合理的情况下,时空特征提取方法可使分类准确率达到90%以上.

关键词： ERPs信号分类时空特征提取法共空间模式支持向量机

Degradation of retinoid X receptor α by TPA through proteasome pathway in gastric cancer cells

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World Journal of Gastroenterology 2003年第9期9卷 1915-1919页

作者： Xiao-Feng Ye Su Liu Qiao Wu Xiao-Feng Lin Bing Zhang Jia-Fa Wu Ming-Qing Zhang Wen-Jin Su key laboratory of the Ministry of Education for Cell Biology and Tumor Cell Engineering,School of Life sciences,xiamen university,xiamen 361.05,Fujian Province,china Xiao-Feng Ye Su Liu Qiao Wu Xiao-Feng Lin Bing Zhang Jia-Fa Wu Ming-Qing Zhang Wen-Jin Su Key Laboratory of the Ministry of Education for Cell Biology and Tumor Cell Engineering School of Life Sciences Xiamen University Xiamen 361005 Fujian Province China

AIM: To investigate and determine the mechanism and signal pathway of tetradecanoylphorbol-1, 3-acetate (TPA) in degradation of RXRα.METHODS: Gastric cancer cell line, BGC-823 was used in the experiments. The expression level of R XRα protein was detected by Western blot. Nuclear and cytoplasmic protein fractions were prepared through lysis of cell and *** and translocation of RXRα were observed under laser-scanning confocal microscope through labeling specific anti-RXRα antibody and corresponding immunofiuorescent antibody as secondary antibody. Different inhibitors were used as ***: In BGC-823 cells, RXRα was expressed in the nucleus. When cells were treated with TPA, expression of RXRα was repressed in a time-dependent and TPAconcentration-dependent manner. Meanwhile, translocation of RXR from the nucleus to the cytoplasm occurred, also in a time-dependent manner. When cells were pre-incubated with proteasome inhibitor MG132 for 3 hrs, followed by TPA for another 12 hrs, TPA-induced RXRα degradation was inhibited. Further observation of RXRα translocation in the presence of MG132 showed that MG-132 could block TPAinduced RXRα redistribution. Conversely, when RXRαtranslocation was inhibited by LMB, an inhibitor for blocking protein export from the nucleus, TPA could not repress expression of RXRα.CONCLUSION: TPA could induce the degradation of RXRα protein in BGC-823 cells, and this degradation is time-and TPA-concentration-dependent. Furthermore, the degradation of RXRα by TPA is via a proteasome pathway and associated with RXRα translocation from the nucleus to the cytoplasm.

关键词：胃癌类维生素A受体X TPA BGC-823细胞

Inhibitory Effects of Salicylic acid Family Compounds on the Diphenolase Activity of Mushroom Tyrosinase

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Inhibitory Effects of Salicylic acid Family Compounds on the...