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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. {2. of nuclear Analysis techniques, Institute of High Energy Physics, chinese academy of sciences, beijing 100049, china 2. Graduate School of chinese academy of sciences, beijing 100049, 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 100049, china 6. Department of Physics, Zhejiang University, Hangzhou 31002., china) key laboratory of {2. Analysis {2. Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China Graduate School of chinese academy of sciences Beijing 100049 China Department of Physics Zhoukou Normal University Zhoukou 466100 China Research Imaging Center University of Texas Health Science Center San Antonio TX 78229 United States National ASIC Design and Engineering Center Institute of Automation Chinese Academy of Sciences Beijing 100049 China Department of Physics Zhejiang University Hangzhou 310027 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 {2. Analysis techniques, Institute of High Energy Physics, chinese academy of sciences, beijing 100049, china 2.Graduate School of the chinese academy of sciences, beijing 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

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 Physics(IMP)and will provide an intense ion beam for nuclear physics,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

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 Energy 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

Prediction of proton-induced SEE error rates for the VATA160 ASIC

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nuclear Science and techniques 2017年第1期28卷 88-93页

作者： Kai Xi Di Jiang shan-shan Gao Jie Kong Hong-Yun Zhao Hai-Bo Yang Tian-Qi Liu Bin Wang Bing Ye Jie Liu Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000 China University of chinese academy of sciences Beijing 100049China State key laboratory of Particle Detection and Electronics University of Science and Technology of ChinaHefei 230026 China

We predict proton single event effect(SEE)error rates for the VATA160 ASIC chip on the Dark Matter Particle Explorer(DAMPE) to evaluate its radiation *** proton test facilities,we built a Monte Carlo simulation tool named PRESTAGE to calculate the proton SEE *** is based on the particle transport toolkit *** adopts a location-dependent strategy to derive the SEE sensitivity of the device from heavy-ion test data,which have been measured at the HI-13 tandem accelerator of the china Institute of Atomic Energy and the heavy-ion research facility in *** AP-8,SOLPRO,and August 1972.worst-case models are used to predict the average and peak proton fluxes on the DAMPE *** results show that the averaged proton SEE error rate for the VATA160 chip is approximately 2.17×10^(-5)/device/***-case error rates for the Van Allen belts and solar energetic particle events are 1-3 orders of magnitude higher than the averaged error rate.

关键词： Proton ASIC Single event effects Error rates

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. {2. techniques Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China key laboratory for Biomedical Effects of Nanomaterials&Nanosafety Institute of High Energy Physics 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

A primary study on biological behavior of aluminum using^2.Al-AMS

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nuclear Science and techniques 2016年第3期27卷 25-30页

作者： Song-Mei Qin Xiang-Gao Wang Xiao-Xi Lan Yun-Ting Gu Ke-Jun Dong Ming He shan Jiang Guangxi University of chinese Medicine Nanning 530001China GXU-NAOC Center for Astrophysics and Space sciences Department of PhysicsGuangxi UniversityNanning 530004China Guangxi key laboratory for the Relativistic Astrophysics Nanning 530004China china Institute of Atomic Energy Beijing 102413China

Aluminum is concerned as a possible cause of many *** investigate the long-term A1 biokinetics and bioavailability in various kinds of Al-contained medicine and food,an accelerator mass spectrometry(AMS)based on the HI-13 tandem has been established for biological analysis with ^(2.)A1(T_(1/2. = 716,000 years) as the *** this paper,the animal tracing,sample preparation procedure and ^(2.)A1-AMS measurement are *** sample preparation procedure has been simplified.A high sensitivity of 5×10^(-15) for ^(2.)A1/^(2.)A1 has been *** phases were found before and after a break time(t_b)for the ^(2.)A1 retained in blood and brain,with t_b≈8 and12.h after the ^(2.)Al tracer injection,respectively.

关键词： AMS 生物学特性铝制备过程生物利用度生物动力学加速器质谱生物分析

利用膜进样质谱仪测定水稻土几种厌氧氮转化速率

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农业环境科学学报 2019年第7期38卷 1541-1549页

作者：李进芳柴延超陈顺涛单军颜晓元中国科学院南京土壤研究所土壤与农业可持续发展国家重点实验室南京210008 中国科学院大学北京100049 中国药科大学南京210009

:为了在同一体系下区分和测定水稻土反硝化、厌氧氨氧化(Anammox)和硝酸根异化还原成铵(DNRA)过程发生速率和相互关系,并获取近似原位情况下的净脱氮速率,本研究通过将15NH4^+化学氧化法测定DNRA速率和添加尿素模拟原位土柱测定净脱氮... 详细信息

:为了在同一体系下区分和测定水稻土反硝化、厌氧氨氧化(Anammox)和硝酸根异化还原成铵(DNRA)过程发生速率和相互关系,并获取近似原位情况下的净脱氮速率,本研究通过将15NH4^+化学氧化法测定DNRA速率和添加尿素模拟原位土柱测定净脱氮速率与膜进样质谱法(MIMS)进行联用,完善了一套基于膜进样质谱法(MIMS)的稻田硝态氮转化测定方法体系,利用该方法测定了5种典型的水稻土[辽宁营口(YK)、江苏宜兴(YX)、浙江金华(JH)、广西桂林(GL)和四川广安(GA)]的反硝化、Anammox、DNRA和净脱氮4种氮转化速率。结果显示:基于MIMS的方法体系可实现对水稻土中反硝化、Anammox、DNRA和净脱氮速率的测定,5种水稻土反硝化、Anammox、DNRA和净脱氮速率范围分别为(358.63±2..37)^(479.96±2..12.、(-14.81±0.2.)^(5.2.±1.2.)、(2..76±12.71)^(109.87±3.88)g N·hm^-2.h^-1和(33.33±11.16)^(72.74±14.18)g N·hm^-2.h^-1,相关结果与其他方法研究结果具有可比性。相关性分析显示:水稻土NO-3、可溶性有机碳(DOC)和土壤Fe^2.含量是反硝化过程的主要限制因素;NO3-是Anammox的关键限制因素;而土壤DOC和Fe^2.含量是DNRA过程的主要限制因素。基于MIMS的方法体系可以在短时间内(1周)测定水稻土四种厌氧氮转化速率,且所需样品量低、精确度高,在稻田或湿地土壤厌氧氮转化过程研究中有很好的应用前景。

关键词：水稻土 15N示踪反硝化厌氧氨氧化硝酸根异化还原成铵