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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. {2. 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 466100, china 4. Research Imaging Center, University of Texas Health Science Center, San Antonio, Texas 782.9, 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 31002., china) [a]key laboratory of {2. 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.

XAFS study on interactions of metallothionein, mercuric chloride and/or sodium selenite

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Acta Geochimica 2006年第S1期 124-124页

作者： Yufeng LI1,2. Chunying CHEN1,2. Jiangxue WANG1,2. Yuxi GAO1,2. Bai LI1,2. Yuliang ZHAO1,2. Zhifang chai1,2.1 key {2. of nuclear Analysis techniques, institute of high energy physics, chinese academy of Sciences, beijing 10004., china 2.Graduate School of the chinese academy of Sciences, {12. 100039, china

Factors affecting the voxel-based analysis of diffusion tensor imaging

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chinese Science Bulletin 2014年第31期59卷 4077-4085页

作者： Jianli Wang Binbin Nie Haitao Zhu Hua Liu Jingjuan Wang Shaofeng Duan baoci shan key laboratory of {2. Radiation and {2. energy Technology Institute of High Energy PhysicsChinese Academy of Sciences beijing Engineering Research Center of Radiographic techniques and Equipment

Diffusion tensor imaging(DTI)provides a unique method to reveal the integrity of white matter microstructure ***-based analysis(VBA),which is a highly reproducible and user-independent technique,has been used to analyze DTI data in a number of *** anisotropy(FA),which is derived from DTI,is the most frequently used *** parameter setting during the DTI data preprocessing might affect the FA analysis ***,there is no reliable evidence on how the parameters affect the results of FA *** study sought to quantitatively investigate the factors that might affect the voxel-based analysis of FA;these include the interpolation during spatial normalization,smoothing kernel and statistical *** it is difficult to obtain the true information of the lesion in the patients,we simulated lesions on the healthy FA *** DTI data were obtained from 2. healthy *** FA maps were calculated using *** randomly divided these FA maps into two *** was used as a model patient group,and the other was used as a normal control *** lesions were added to the model patient group by decreasing the FA intensities in a specified region by 5%–50%.The model patient group and the normal control group were compared by two-sample t test statistic analysis voxelby-voxel to detect the simulated *** evaluated these factors by comparing the difference between the detected lesion through VBA and the simulated *** result showed that the space normalization of FA image should use the trilinear interpolation,and the smoothing kernel should be 2.3 times the voxel size of spatially normalized FA *** lesions with small intensity change,FWE correction must be cautiously *** study provided an important reference to the analysis of FA with VBA method.

关键词：扩散张量体素成像三线性插值可能影响统计分析结构完整性预处理过程

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磁约束聚变堆中的润滑研究

摩擦学学报（中英文） 2024年第3期44卷 421-436页

作者：张瑞张弘柴利强王鹏中国科学院兰州化学物理研究所固体润滑国家重点实验室甘肃兰州730000 中国科学院大学北京100049

核聚变反应可以提供近乎无限的能源,且是1种安全清洁的方式.磁约束核聚变通过强磁场约束高温高密度氘氚等离子体放电发生聚变反应产生能源,其装备结构复杂且服役环境恶劣.服役于磁约束聚变装置中的活动部件使用的润滑材料不仅面临着摩... 详细信息

核聚变反应可以提供近乎无限的能源,且是1种安全清洁的方式.磁约束核聚变通过强磁场约束高温高密度氘氚等离子体放电发生聚变反应产生能源,其装备结构复杂且服役环境恶劣.服役于磁约束聚变装置中的活动部件使用的润滑材料不仅面临着摩擦磨损还要承受聚变装置高低温、真空以及辐射环境.本文中系统地总结了磁约束聚变装置发展过程中真空室、超导磁场、离子回旋加热系统和遥操作系统等各个部件面临的润滑挑战以及解决方案,并对未来商用磁约束聚变堆所需润滑材料与技术进行了展望.

关键词：聚变堆辐照结构遥操润滑

Distinct Roles of Dopamine Receptors in the Lateral Thalamus in a Rat Model of Decisional Impulsivity

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Neuroscience Bulletin 2017年第4期33卷 413-422页

作者： Zhiyan Wang Shengxiang Liang Shuangshuang Yu Tong Xie Baicheng Wang Junkai Wang Yijing Li baoci shan Cailian Cui Neuroscience Research institute Peking UniversityBeijing 100191China Department of Neurobiology School of Basic Medical SciencesPeking UniversityBeijing 100191China key laboratory of Neuroscience The Ministry of Educationand Ministry of Public HealthBeijing 100191China Division of nuclear Technology and Applications Instituteof High Energy PhysicsChinese Academy of SciencesBeijing 100049China

The thalamus and central dopamine signaling have been shown to play important roles in high-level cognitive processes including impulsivity. However, little is known about the role of dopamine receptors in the thalamus in decisional impulsivity. In the present study,rats were tested using a delay discounting task and divided into three groups： high impulsivity（HI）, medium impulsivity（MI）, and low impulsivity（LI）. Subsequent in vivo voxel-based magnetic resonance imaging revealed that the HI rats displayed a markedly reduced density of gray matter in the lateral thalamus compared with the LI rats. In the MI rats, the dopamine D1 receptor antagonist SCH2.390 or the D2.receptor antagonist eticlopride was microinjected into the lateral thalamus. SCH2.390 significantly decreased their choice of a large, delayed reward and increased their omission of lever presses. In contrast,eticlopride increased the choice of a large, delayed reward but had no effect on the omissions. Together, our results indicate that the lateral thalamus is involved in decisional impulsivity, and dopamine D1 and D2.receptors in the lateral thalamus have distinct effects on decisional impulsive behaviors in rats. These results provide a new insightinto the dopamine signaling in the lateral thalamus in decisional impulsivity.

关键词： Lateral thalamus Decisional impulsivity D1 receptor D2.receptor

Two-plane painting injection scheme for BRing of HIAF

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nuclear Science and techniques 2017年第8期28卷 47-53页

作者： Guo-Feng Qu Wei-Ping chai Jia-Wen Xia Jian-Cheng Yang Heng Du Zhong-shan Li Wen-Wen Ge Wen-Heng Zheng Peng shang institute of Modern physics Chinese Academy of SciencesLanzhou 730000 China University of chinese academy of Sciences Beijing 100046China

The high-intensity heavy-ion accelerator facility(HIAF)is under design at the institute of Modern {2.(IMP)and will provide an intense ion beam for nuclear {2.,atomic mass measurement research,and other *** the main ring of HIAF,the BRing accumulates beams to high intensity and accelerates them to high *** achieve high intensities up to 1×10^(11)(^(2.8)U^(34+)),the injection gain of the BRing must be as high as ***,multiple multiturn injection supported by the electron cooling system takes a long time,causing substantial beam loss under a strong space charge ***,a two-plane painting injection scheme is proposed for beam accumulation in the *** scheme uses a tilted injection septum and horizontal and vertical bump magnets to paint the beam into horizontal and vertical phase space *** this paper,the two-plane painting injection parameters are optimized,and the resulting injection process is simulated using the Objective Ring Beam Injection and Tracking(ORBIT)*** injection gain of up to 110.3 with a loss rate of 2.3%is achieved,meeting the requirements of BRing.

关键词：绘画平面近代物理研究所注射过程重离子加速器电子冷却系统束流损失纵向相空间

A combined DFT and molecular dynamics study of U(Ⅵ)/calcite interaction in aqueous solution

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Science Bulletin 2017年第15期62卷 1064-1073页

作者： Jian-Hui Lan Zhi-Fang chai Wei-Qun Shi laboratory of nuclear {2. Chemistry and Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China School of Radiological and Interdisciplinary Sciences (RAD-X) and Collaborative Innovation Center of Radiation Medicine of Jiangsu higher Education Institutions Soochow University Suzhou 215123 China

Here we present a combined DFF and molecular dynamics study of uranyl （U（VI）） interaction mecha- nisms with the calcite （104） surface in aqueous solution. The roles of three anion ligands （CO2., HCO3, OH ） and solvation effect in U（VI） interaction with calcite have been evaluated. According to our calculations, water adsorbed on the calcite （104） surface prefers to exist in molecular state rather than dis- sociative state. energy analysis indicate that the positively charged uranyl species prefers to form surface complexes on the surface, while neutral uranyl species may bind with the surface via both surface complexing and ion exchange reactions of U（VI） → Ca（II）. In contrast, the negatively charged uranyl species prefer to interact with the surface via ion exchange reactions of U（VI）→ Ca（II）, and the one with UO2.CO3）2.H2.）^2. as the reactant becomes the most favorable one in energy. We also found that uranyl adsorption increases the hydrophilicability of the （104） surface to different extents, where the UO2.CO3）3Ca2.species contributes to the largest degree of energy changes （ 53 kcal/mol）. Our calcula- tions proved that the （104） surface also has the ability to immobilize U（VI） via either surface complexing or ion exchange mechanisms under different pH values.

关键词： Uranyl Incorporation Adsorption Calcite Density functional theory Molecular dynamics

Spherical nanoindentation stress–strain responses of SIMP steel to synergistic effects of irradiation by H and He ions

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nuclear Science and techniques 2022年第6期33卷 139-147页

作者： Peng Jin Tie-Long Shen Jing Li Yu-shan Yang Jian-Long chai Ya-Bin Zhu Ming-Huan Cui Chao Liu Tong-Min Zhang Long Kang Jun Li Jin-Yu Li Shuo-Xue Jin Xing-Zhong Cao Zhi-Guang Wang institute of Modern physics Chinese Academy of SciencesLanzhou 730000China School of nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100049China institute of high {2. physics Chinese Academy of SciencesBeijing 100049China

A novel Fe-10Cr ferritic/martensitic steel called SIMP was chosen to investigate synergistic effects of H and He on the mechanical properties of structural materials for innovative nuclear energy systems. Sequential and separate irradiation experiments on SIMP steel specimens at room temperature using H and He ions with various energy levels were conducted to produce an ion deposition plateau at 300-650 nm. The indentation stress-strain responses were examined using spherical nanoindentation tests after the irradiation experiments. It was found that the sequential irradiation by He and H produced a higher indentation yield stress than separate irradiation, indicating that the hardening was enhanced by the synergy of the H and He irradiation. The micro-mechanism responsible for enhancing the hardening of the SIMP steel through the H and He synergy was investigated using Doppler broadening spectroscopy detection and transmission electron spectroscopy observations.

关键词： H/He irradiation Spherical nanoindentation Bubbles Dislocation loops

Mesoporous silica SBA-15 functionalized with phosphonate and amino groups for uranium uptake

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Science china Chemistry 2012年第9期55卷 1705-1711页

作者： WANG XiaoLiang YUANLiYong WANG YanFei LI ZiJie LIU YaLan FENG YiXiao ZHAO YuLiang chai ZhiFang SHI WeiQun Department of Applied Chemistry School of Chemistry and Chemical EngineeringUniversity of South ChinaHengyang 421001China key laboratory of {2. analytical techniques Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China key laboratory for Biomedical Effects of Nanomaterials&Nanosafety{2. Chinese Academy of SciencesBeijing 100049China

Mesoporous silicas have a very attractive ability of sorption and enrichment of metal ions due to their huge surface area and facile functionalization by organic ligands. In this work, phosphonate-amino hifunctionalized mesoporous silica SBA-15 （PA-SBA-15） as U（VI） sorbent was fabricated through post-grafting method. The obtained mesoporous silica was character- ized by SEM, XRD, NMR and nitrogen sorption/desorption experiments, which revealed the existence of ordered mesoporous structure with uniform pore diameter and large surface area. The adsorptivity of PA-SBA-15 for U（VI） from aqueous solution was investigated using batch sorption technique under different experimental conditions. The preliminary results show that the U（VI） sorption by PA-SBA-15 is very quick with equilibrium time of less than 1 h, and the U（VI） uptake is as large as 373 mg/g at pH 5.5 under 95℃. The sorption isotherm has been successfully modeled by the Langmuir isotherm, suggesting a monolayer homogeneous sorption of U（VI） in PA-SBA-15. The sorption is pH-dependent due to the pH-dependent charge of sorbent in the aqueous solution. The thermodynamics research shows that the sorption is a feasible and endothermic process. Based on these results, PA-SBA-15 could be a promising solid phase sorbent for highly-efficient removal of U（VI） ions from waste water and enrichment of U（VI） from a solution at a very low level.

关键词： mesoporous silica SBA-15 phosphonate amino group bifunctionalized sorption uranium