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fMRI time series analysis based on stationary wavelet and spectrum analysis

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Progress in Natural Science:Materials International 2006年第11期16卷 1171-1176页

作者： ZHI Lianhe~ 1,2,3 , ZHAO Xia~4. SHAN Baoci~1**, PENG Silong~5, YAN Qiang~1, YUAN Xiuli~1 and TANG Xiaowei~ 1,6 (1. Key Laboratory of Nuclear analysis Techniques, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 10004., china 2. Graduate School of Chinese Academy of Sciences, Beijing 10004., china 3. Department of Physics, Zhoukou Normal university, Zhoukou 4.6100, china 4. Research Imaging center, university of Texas Health Science center, San Antonio, Texas 78229, USA 5. National ASIC Design and Engineering center, Institute of Automation, Chinese Academy of Sciences, Beijing 10004., china 6. Department of Physics, zhejiang university, Hangzhou 310027, china) [a]Key Laboratory of Nuclear analysis Techniques Institute of High Energy Physics Chinese Academy of Sciences Beijing China [b]Graduate School of Chinese Academy of Sciences Beijing China [c]Department of Physics Zhoukou Normal University Zhoukou China [d]Research Imaging center University of Texas Health Science Center San Antonio Texas USA [e]National ASIC Design and Engineering center Institute of Automation Chinese Academy of Sciences Beijing China [f]Department of Physics Zhejiang University Hangzhou China

The low signal to noise ratio (SNR) of functional MRI (fMRI) prefers more sensitive data analysis methods. Based on stationary wavelet transform and spectrum analysis, a new method with high detective sensitivity was developed for analyzing fMRI time series, which does not require any prior assumption of the characteristics of noises. In the proposed method, every component of fMRI time series in the different time-frequency scales of stationary wavelet transform was discerned by the spectrum analysis, then the components from noises were removed using the stationary wavelet transform, finally the components of real brain activation were detected by cross-correlation analysis. The results obtained from both simulated and in vivo visual experiments illustrated that the proposed method has much higher sensitivity than the traditional cross-correlation method.

关键词： fMRI stationary wavelet transform spectrum analysis data analysis.

Surface investigation on Upilex-S polymide film iradiated by vacuum ultraviolet radiation

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Rare Metals 2007年第S1期26卷 168-174页

作者： LIU Yuyan1),GONG Xianyun2),WAN Zhimin3),and DU Xingwen4.1) Department of Applied Chemistry,Harbin Institute of Technology,Harbin 150001,china 2) Department of Life Science and Chemistry,Harbin university,Harbin 150001,china 3) analysis and {4. center,Harbin Institute of Technology,Harbin 150001,china 4. center for Composite Materials,Harbin Institute of Technology,Harbin 150001,china Harbin Inst Technol Dept Appl Chem Harbin 150001 Peoples R China Harbin Univ Dept Life Sci & Chem Harbin 150001 Peoples R China Harbin Inst Technol Ctr Anal & Measurement Harbin 150001 Peoples R China Harbin Inst Technol Ctr Composite Mat Harbin 150001 Peoples R China

Vacuum ultraviolet radiation of Upilex-S polyimide film 25 μm thick was performed using a gas jet type of vacuum ultraviolet simulator which gives unfixed wavelength from 5 nm to 200 *** redeposited on the films were observed and the nanoparticles formed on the surface consist mainly of carbon *** in the composition and the chemical characteristics of film surface after radiation were identified by X-ray photoelectron spectroscopy(XPS).Relative O content in the radiated area was found to be higher,while N content was lower than in the pristine *** indicates that Upilex-S polyimide film releases N atoms as volatile *** the C1s,O1s envelopes were fitted using Multipak Spectrum *** surface morphologies on iradiated area were examined by Atomic Force Microscope(AFM).Pieces of radiant products protrude from the eradiated surface,leading to considerable roughness for the iradiated *** the surface transmittance of Upilex-S film after radiation reduces.

关键词： vacuum ultraviolet radiation Upilex-S polyimide film

Is There any Hexazirconium Cluster in the Compounds [HP(t-Bu)_2Ph_3]_3[Zr_6Cl_(18)H_5] and Zr_6Cl_(14.(PPr_3)_4._4.

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Chinese Chemical Letters 1997年第9期8卷 829-830页

作者： Wen LI ChunHua HU Pei Ju ZHENG(Research center of analysis and measurement, Fudan university, Shanghai 2004.3) FUDAN UNIV RES CTR ANAL & MEASUREMENTSHANGHAI 200433PEOPLES R CHINA

The [Zr6(μ2-Cl)12Cl6H4.3- ion with C4. Symmetry in the title compounds has been calculated by DV-Xα program. The calculated results show that ther is almost no available covalence bonding between zirconium atoms and significant Zr 4. AO compositions in the MOs. but there are much stronger Zr-Cl(bridging) bonding. All analysis results suggest that these compounds would be the cluster with Zr6Cl12 cage linked by Zr-Cl bridging bonding plus six Cl teminal ligands rather than the hexazirconium cluster in view of the chemical bonding.

关键词： and Zr6Cl PPr3 Is There any Hexazirconium Cluster in the Compounds t-Bu H5 Zr6Cl HP

Pollen morphology of Rhododendron subgen. Tsutsusi and its systematic implications

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Journal of Systematics and Evolution 2009年第2期47卷 123-138页

作者： 1,2Yue-Jiao ZHANG 1Xiao-Feng JIN 3Bing-Yang DING 4.ing-Ping ZHU 1(School of Life & Environment Sciences,Hangzhou Normal university,Hangzhou 310036,china) 2(College of Life Sciences,zhejiang university,Hangzhou 310012,china) 3(School of Life & Environment Sciences,Wenzhou university,Wenzhou 325027,china) 4.center of analysis & measurement,zhejiang university,Hangzhou 310028,china) ( center of analysis & measurement Zhejiang University Hangzhou 310028 China )

Eighty-four pollen samples were obtained for 80 taxa,of which,13 species and one variety are from *** Sweet,58 species and two varieties from *** Sweet,and six species from ***(***) Pojarkova,*** morphology of all samples was observed using LM and *** grains are revealed to be spheroidal and tetrahedral with tricolporate *** sizes of ***(Sweet) Pojarkova range from 37.67 μm to 61.06 μm,and the exine sculptures are more or less compactly *** sizes are significantly different between *** and *** of *** tashiroi *** *** Sleumer shows a close affinity to *** size and exine are consistent with general morphology in differentiating species in *** huadingense *** & ***,once placed as a member of ***,should be considered as a species in ***.

关键词： Ericaceae Rhododendron subgen.Tsutsusi pollen morphology tetrahedral tetrads systematic implication

Orientation-Singularity Representation and Orientation-Capability Computation of a Special Class of the Gough-Stewart Parallel Mechanisms Using Unit Quaternion

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Chinese Journal of Mechanical Engineering 2012年第6期25卷 1096-1104页

作者： LI Baokun1, 2, CAO Yi1, 3, *, ZHANG Qiuju1, and HUANG Zhen4.1 School of Mechanical Engineering, Jiangnan university, Wuxi 214.22, china 2 School of Mechanical Engineering, Anhui university of Science and Technology, Huainan 232001, china 3 State Key Laboratory of Fluid Power Transmission and Control, Hangzhou 310027, china 4.Robotics Research center, Yanshan university, Qinhuangdao 066004. china 1. School of Mechanical Engineering Jiangnan University Wuxi 214122 China 2. School of Mechanical Engineering Anhui University of Science and Technology Huainan 232001 China 3. State Key Laboratory of Fluid Power Transmission and Control Hangzhou 310027 China 4. Robotics Research center Yanshan University Qinhuangdao 066004 China

Singular configuration seriously affects the performance of the Gough-Stewart parallel mechanism and has attracted many researchers’ attentions. However, most of existing topics often focus on the position-singularity of the mechanism for a constant-orientation, but few reports research the orientation-singularity for a given position. In order to investigate the orientation-singularity of the Gough-Stewart parallel mechanisms with two dissimilar semi-regular hexagonal platforms for a given position, after constructing the discrimination matrix of the singular configuration of the mechanism and computing the determinant of this matrix by using unit quaternion as the orientation parameters which can avoid the singularities in parameterization, a general symbolic expression representing the three-dimensional orientation-singularity locus for a given position is obtained and the three-dimensional view of the orientation-singularity locus is further described. The orientation-singularity-free void exists inside the orientation-singularity locus, but the shape of the orientation-singularity-free void is irregular and inconvenient for the design of the mechanism. The minimal inscribed sphere of the three-dimensional orientation-singularity locus namely the orientation-singularity-free ball is described. The radius of the ball orientation-capability is used as the measurement for the orientation-singularity-free void size. A new efficient algorithm is proposed for the computation of the orientation-capability. Finally, the influences of the geometry parameters and the different positions of the mechanism on the orientation-capability are discussed. A new method of the singularity analysis of the Gough-Stewart parallel mechanism is advanced based on the unit quaternion, and the research finds have important referential value for the configuration parameters optimization of this class of the parallel mechanisms with the goal of having the maximal singularity-free zone.

关键词： parallel mechanism unit quaternion orientation-singularity orientation-singularity-free void orientation-capability

Patterns of platinum-group elements in mantle peridotite, granulite xenoliths and basalt in Hannuoba

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Chinese Science Bulletin 1999年第18期44卷 1676-1681页

作者： CHU Xuelei, LI Xiaolin, XU Jiuhua and LIU Jianming1. The Research center of Mineral Resources Exploration , Chinese Academy of Sciences , Beijing 100101, china 2. Institute of Geology , Chinese Academy of Sciences , Beijing 100029, china 3. Institute of High Energy Physics , Chinese Academy of Sciences , Beijing 100817 , china 4. Beijing {4. of Science and Engineering , Beijing 100083, china Corresponding author The Research center of Mineral Resources Exploration Chinese Academy of Sciences Beijing China Institute of Geology Chinese Academy of Sciences Beijing China Institute of High Energy Physics Chinese Academy of Sciences Beijing China Beijing university of Science and Engineering Beijing China

Neutron activation analysis after preconcentration of nickel sulfide fire assay was used in measurement of Ru, Ph, Pd, Os, Ir, Pt (i.e. PGE elements) and Au concentrations for basalt, mantle and granulite xenoliths in Hannuoba. The chondrite- and primitive mantle-normalized PGE patterns generally exhibit flat (for Iherzolite), negative slope (for harzburgite),

关键词： mantle xenolith granulite xenolith basalt platinum-group element Hannuoba.

Comparison of dark energy models:A perspective from the latest observational data

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中国科学：物理学、力学、天文学英文版 2010年第9期53卷 1631-1645页

作者： LI Miao1,2,LI XiaoDong2,3 & ZHANG Xin1,4.1Kavli Institute for Theoretical Physics china,Chinese Academy of Sciences,Beijing 100190,china 2Key Laboratory of Frontiers in Theoretical Physics,Institute of Theoretical Physics,Chinese Academy of Sciences,Beijing 100190,china 3Interdisciplinary center for Theoretical Study,{4. of Science and Technology of china,Hefei 230026,china 4.epartment of Physics,College of Sciences,Northeastern {4.,Shenyang 110004.china 1. Kavli Institute for Theoretical Physics china Chinese Academy of Sciences Beijing 100190 China2. Key Laboratory of Frontiers in Theoretical Physics Institute of Theoretical Physics Chinese Academy of Sciences Beijing 100190 China3. Interdisciplinary Center for Theoretical Study University of Science and Technology of China Hefei 230026 China4. Department of Physics College of Sciences Northeastern University Shenyang 110004 China

We compare some popular dark energy models under the assumption of a flat universe by using the latest observational data including the type Ia supernovae Constitution compilation,the baryon acoustic oscillation measurement from the Sloan Digital Sky Survey,the cosmic microwave background measurement given by the seven-year Wilkinson Microwave Anisotropy Probe observations and the determination of H0 from the Hubble Space *** comparison statistics such as the Bayesian and Akaike information criteria are applied to assess the worth of the *** statistics favor models that give a good fit with fewer *** on this analysis,we find that the simplest cosmological constant model that has only one free parameter is still preferred by the current *** other dynamical dark energy models,we find that some of them,such as the αdark energy,constant w,generalized Chaplygin gas,Chevalliear-Polarski-Linder parametrization,and holographic dark energy models,can provide good fits to the current data,and three of them,namely,the Ricci dark energy,agegraphic dark energy,and Dvali-Gabadadze-Porrati models,are clearly disfavored by the data.

关键词： dark energy models observational constraints model comparison information criteria

Synthesis of Novel SnO_2 Quantum Cubes and Their Selfassembly

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Journal of Wuhan university of Technology(Materials Science) 2011年第2期26卷 270-273页

作者：俞中平王智宇 State Key Laboratory of Silicon Materials Department of Materials Science and EngineeringZhejiang University

Nano-structured cubic SnO2 crystalines were successfully synthesized through solvothermal *** obtained products were characterized by X-ray diffraction （XRD）,transmission electron microscopy （TEM） and high resolution TEM （HRTEM）.The study showed that,the SnO2 particles were rutile structured and almost uniformly cube shaped crystals in quantum size （3-8 nm）.Self-assembly behavior of the cubic SnO2 quantum dots was also *** synthesis process can be defined as an nonhydrolysis （NH） hydroxylation reaction provided by the amide elimination of carboxylated *** formation of cubic morphology of SnO2 can be ascribed to the mild reaction featured by high nucleation rate and low growth rate,surface energy difference of the crystallographic facets of SnO2 and the passivation effect of the starting material-dodecylamine which drastically reduced the dipole *** selfassembly of the cubic SnO2 quantum dots was driven by van der Waals force and capillary force.

关键词： nanocube quantum dot crystal growth tin oxide

Gravity Changes Before Large Earthquakes in china: 1998-2005

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地球空间信息科学学报（英文） 2011年第1期14卷 1-9页

作者： ZHAN F. Benjamin ZHU Yiqing NING Jinsheng ZHOU Jiangcun LIANG Weifeng XU Yunma School of Resource and Envirorunental Science Wuhan University 129 Luoyu Road Wuhan 430079 China Texas center for Geographic Information Science Texas State University San Marcos TX 78666 USA Institute of Geodesy and Geophysics Chinese Academy of Sciences 340 Xudong Street Wuhan 430077 China Second Crust Monitoring and Application center China Earthquake Administration Xi'An 710054 China School of Geodesy and Geomatics Wuhan University 129 Luoyu Road Wuhan 430079 China

Although it is well known that coseismic gravity changes take place during an earthquake, previous research has not yielded convincing evidence demonstrating that significant gravity changes occur before large earthquakes. Furthermore, even if we suspect that gravity changes occur before large earthquakes, we have yet to demonstrate how to consistently observe these changes for useful earthquake forecast that would bring benefits to society. We analyzed ground gravity survey data obtained in 1998, 2000, 2002, and 2005 at stations of the Crustal Movement Observation Network of china (CMONOC) and examined gravity changes be-fore the occurrence of nine large (Ms≥6.8) earthquakes that ruptured within or near china's Mainland and Taiwan from November 2001 to August 2008. Results from this analysis show that significant gravity changes occurred across a large region before each of these nine large earthquakes, and these changes were detected by repeated ground gravity surveys through CMONOC. Although these gravity changes were significant, more research is needed to investigate whether these gravity changes could be viewed as precursors of large earthquakes. Limitations and uncertainties in the data include sparseness of the gravity monitoring network, long time intervals between consecutive gravity surveys, inevitable measurement errors, hydrological effects on gravity, and effects of vertical crustal movements on gravity. Based on these observations, we make several recommendations about possible future direc-tions in earthquake-related research using gravity monitoring data.

关键词： earthquake gravity seismology china Wenchuan geodesy GIS