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HI-13串列加速器升级工程在线同位素分离器高质量分辨谱仪物理设计 被引量:6
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作者 彭朝华 关遐令 崔保群 《原子能科学技术》 EI CAS CSCD 北大核心 2006年第2期133-138,共6页
HI-13串列加速器升级工程中的在线同位素分离器(ISOL)高质量分辨谱仪要求20 000的质量分辨率。本工作采用大小铁双能量结构削弱能量色散,有效解决了束流能散过大导致的谱仪质量分辨率低的问题。结果表明:当束流高斯分布宽度为0.06 mm和1... HI-13串列加速器升级工程中的在线同位素分离器(ISOL)高质量分辨谱仪要求20 000的质量分辨率。本工作采用大小铁双能量结构削弱能量色散,有效解决了束流能散过大导致的谱仪质量分辨率低的问题。结果表明:当束流高斯分布宽度为0.06 mm和10 mrad时,谱仪的质量分辨率达到了33 400;若考虑加速段引入的0.002%能散,谱仪最终的质量分辨率为20 000。 展开更多
关键词 在线同位素分离器 高质量分辨 能量色散 谱仪
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在线同位素分离器监控系统的研制
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作者 马瑞刚 崔保群 +4 位作者 马鹰俊 唐兵 陈立华 黄青华 马燮 《原子能科学技术》 EI CAS CSCD 北大核心 2019年第9期1565-1571,共7页
在线同位素分离器(ISOL)装置是HI-13串列加速器升级工程中产生放射性核束及13MeV串列加速器的注入部分,其能产生多种放射性核束,具有高质量分辨率的特点。为实现该装置的监控任务,结合ISOL的分布情况和特点,设计了一套PLC框架下构建的... 在线同位素分离器(ISOL)装置是HI-13串列加速器升级工程中产生放射性核束及13MeV串列加速器的注入部分,其能产生多种放射性核束,具有高质量分辨率的特点。为实现该装置的监控任务,结合ISOL的分布情况和特点,设计了一套PLC框架下构建的基于以太网的分布式控制系统。本文介绍受控设备的特点、控制方式、监控系统的基本结构、安全联锁和抗干扰设计、图形化监控软件设计、数据存储方式及运行情况。 展开更多
关键词 在线同位素分离器 监控系统 高质量分辨 控制接口 安全联锁和抗干扰
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一种基于质谱仪的数字滤波器参数设计方法研究 被引量:2
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作者 章燕妮 李畅 +8 位作者 刘梅英 楚士颖 安育庭 徐锐锋 黄泽建 戴新华 方向 俞晓平 江游 《中国计量大学学报》 2021年第3期298-303,共6页
目的:数字滤波器可以提高质谱仪信噪比。针对数字滤波器参数设置不当会降低质谱仪质量分辨率以及浪费系统资源的问题,提出一种数字滤波器参数设计的方法。方法:根据滤波前后质量分辨率变化规律、限定质量分辨率增量以及基线信号强度变化... 目的:数字滤波器可以提高质谱仪信噪比。针对数字滤波器参数设置不当会降低质谱仪质量分辨率以及浪费系统资源的问题,提出一种数字滤波器参数设计的方法。方法:根据滤波前后质量分辨率变化规律、限定质量分辨率增量以及基线信号强度变化,完成了数字滤波器的窗函数、阶数及最佳截止频率的参数设计。结果:在实验室自主研制的四极杆-线形离子阱串联质谱仪中,使用本方法实现了hamming窗低通数字滤波器的设计,将仪器信噪比提升71%,同时分辨率降低量小于1%。结论:该方法在提高质谱仪信噪比和分辨率的同时,减少了系统资源浪费,为高灵敏质谱仪研发提供了参考方法。 展开更多
关键词 数字滤波器 四极杆-线形离子阱串联质谱仪 高质量分辨 信噪比
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二噁英、多氯联苯和氯丙醇的痕量与超痕量检测技术研究 被引量:8
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作者 吴永宁 《中国食品卫生杂志》 2005年第6期481-486,共6页
为建立食品中二噁英、多氯联苯和氯丙醇的检测技术并达到国际水平,将稳定性同位素稀释质谱技术应用到中国食品安全和环境分析领域,针对不同目标化合物分别建立了高分辩磁质谱、四极杆低分辩质谱和离子阱串联质谱的标准化检测技术,特别... 为建立食品中二噁英、多氯联苯和氯丙醇的检测技术并达到国际水平,将稳定性同位素稀释质谱技术应用到中国食品安全和环境分析领域,针对不同目标化合物分别建立了高分辩磁质谱、四极杆低分辩质谱和离子阱串联质谱的标准化检测技术,特别是采用双同位素稀释同时测定4种氯丙醇的技术。通过对EPA1613A1668A、FDA4084和EPS1RM31、AOAC2000.01等国际先进方法用食品(鱼、鱼油、鹿肉、奶粉和猪油)和环境样品(飞灰、土壤和底泥)开展对比筛选和一系列实验室间协同性验证,确立了二英和多氯联苯的稳定性同位素稀释质谱检测方法,建立了用双稳定性同位素进行酱油中单氯取代和双氯取代氯丙醇同时测定的方法,提出了符合国际规范的技术方案,作为国家标准方法待颁布。利用该检测技术在中国首次开展鱼贝类和土壤中污染的二英和多氯联苯同系物类型特征指纹库研究和酱油中氯丙醇的大规模调查,获得了中国人群膳食二英毒性当量和氯丙醇摄入状况的暴露数据,不仅证明所建立的方法实用、可行,也为我国履行承诺摸清了家底,提供了依据。 展开更多
关键词 多氯联苯化舍物 二噁英类 同位素稀释技术 分辨质量
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On the initiation,movement and deposition of a large landslide in Maoxian County,China 被引量:3
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作者 pei xiang-jun guo bin +3 位作者 cui sheng-hua wang dong-po xu qiang li tian-tao 《Journal of Mountain Science》 SCIE CSCD 2018年第6期1319-1330,共12页
At 5 am 24 th June 2017, a catastrophic landslide hit Xinmo Village, Maoxian County, Sichuan Province, China. The slide mass rushed down from an altitude of 3400 m and traveled 2700 m in a high velocity. The 13 millio... At 5 am 24 th June 2017, a catastrophic landslide hit Xinmo Village, Maoxian County, Sichuan Province, China. The slide mass rushed down from an altitude of 3400 m and traveled 2700 m in a high velocity. The 13 million m^3 deposition buried the whole village and caused about 100 deaths. The source area of the landslide is located in a high steep slope, average slope angle is 40o and maximal angle is 65o. The strata are interbedded Triassic Zagunao Formation metamorphic sandstone and slate with the dip slope angle of 45°. Based on high-resolution satellite remote sensing image, UAV image, DEM data, and field investigation, failure mechanism, travel features, and deposit characteristics were analyzed. The results showed that this landslide was influenced by Songpinggou Fault zone. According to the topography before the failure, the landslide is located in the back scarp of an antecedent landslide induced by Diexi Earthquake in 1933. The bedding slope provided potential rupture surface. Historical seismic activities and long-term gravitational deformation caused rock mass accumulated damages. Weathering and precipitation weakened the rock mass and finally induced shearing and tension failure. A huge block detached from the top rock slope, pushed the past landslide deposits in the middle part, rushed out of the slope bottom in a high velocity and buried the Xinmo Village. The rapid movement entrained and brought the soil into the Songping Gully which recoiled with and bounced back from the opposite mountain. 展开更多
关键词 Xinmo landslide Seismic damages Longrunout Failure mechanism Rock fragment
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Determination of trace elements in high purity nickel by high resolution inductively coupled plasma mass spectrometry 被引量:11
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作者 聂西度 梁逸曾 +1 位作者 唐有根 谢华林 《Journal of Central South University》 SCIE EI CAS 2012年第9期2416-2420,共5页
The contents ofMg, Al, Si, Ti, Cr, Mn, Fe, Co, Cu, Ga, As, Se, Cd, Sb, Pb and Bi in high purity nickel were determined by high resolution inductively coupled plasma mass spectrometry (HR-ICP-MS). The sample was diss... The contents ofMg, Al, Si, Ti, Cr, Mn, Fe, Co, Cu, Ga, As, Se, Cd, Sb, Pb and Bi in high purity nickel were determined by high resolution inductively coupled plasma mass spectrometry (HR-ICP-MS). The sample was dissolved in HNO3 and HCI by microwave digestion. Most of the spectral interferences could be avoided by measuring in the high resolution mode. The matrix effects because of the presence of excess HC1 and nickel were evaluated. Correction for matrix effects was made using Sc, Rh and T1 as internal standards. The optimum conditions for the determination were tested and discussed. The detection limits range from 0.012 to 1.76 ~tg/g depending on the type of elements. The applicability of the proposed method is also validated by the analysis of high purity nickel reference material (NIST SRM 671). The relative standard deviation (RSD) is less than 3.3%. Results for determination of trace elements in high purity nickel were presented. 展开更多
关键词 high resolution inductively coupled plasma mass spectrometry high purity nickel trace element matrix effect internal standard
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Ultra High Energy Cosmic Rays: Spectral Signatures and Observations
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作者 Svetlana Grigorieva 《Journal of Physical Science and Application》 2014年第6期393-397,共5页
The observations of Ultra High Energy Cosmic Rays (UHECR) are renewed, focusing on the energy spectra as measured by HiRes, Telescope Array (TA) and Auger detectors (PAO). It is found that highest energy Auger s... The observations of Ultra High Energy Cosmic Rays (UHECR) are renewed, focusing on the energy spectra as measured by HiRes, Telescope Array (TA) and Auger detectors (PAO). It is found that highest energy Auger steepening does not agree with GZK cutoff, which is most probably explained by the nuclei mass composition detected by Auger. At present the difference in mass composition in Auger and HiRes/TA data remains the main unsolved problem of UHECR origin. 展开更多
关键词 Ultrahigh energy cosmic ray origin CMB radiation GZK cutoff.
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Review of pre-processing technologies for ice cores
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作者 DU Wen-tao KANG Shi-chang +4 位作者 QIN Xiang SUN Wei-jun ZHANG Yu-lan LIU Yu-shuo CHEN Ji-zu 《Journal of Mountain Science》 SCIE CSCD 2018年第9期1950-1960,共11页
High-resolution ice core records covering long time spans enable reconstruction of the past climatic and environmental conditions allowing the investigation of the earth system's evolution. Preprocessing of ice co... High-resolution ice core records covering long time spans enable reconstruction of the past climatic and environmental conditions allowing the investigation of the earth system's evolution. Preprocessing of ice cores has direct impacts on the data quality control for further analysis since the conventional ice core processing is time-consuming, produces qualitative data, leads to ice mass loss, and leads to risks of potential secondary pollution. However, over the past several decades, preprocessing of ice cores has received less attention than the improvement of ice drilling, the analytical methodology of various indices, and the researches on the climatic and environmental significance of ice core records. Therefore, this papers reviews the development of the processing for ice cores including framework, design as well as materials, analyzes the technical advantages and disadvantages of the different systems. In the past, continuous flowanalysis(CFA) has been successfully applied to process the polar ice cores. However, it is not suitable for ice cores outside polar region because of high level of particles, the memory effect between samples, and the filtration before injection. Ice core processing is a subtle and professional operation due to the fragility of the nonmetallic materials and the random distribution of particles and air bubbles in ice cores, which aggravates uncertainty in the measurements. The future developments of CFA are discussed in preprocessing, memory effect, challenge for brittle ice, coupling with real-time analysis and optimization of CFA in the field. Furthermore, non-polluting cutters with many different configurations could be designed to cut and scrape in multiple directions and to separate inner and outer portions of the core. This system also needs to be coupled with streamlined operation of packaging, coding, and stacking that can be implemented at high resolution and rate, avoiding manual intervention. At the same time, information of the longitudinal sections could be scanned andidentified, and then classified to obtain quantitative data. In addition, irregular ice volume and weight can also be obtained accurately. These improvements are recorded automatically via user-friendly interfaces. These innovations may be applied to other paleomedias with similar features and needs. 展开更多
关键词 Ice core Alpine region Polar region PRE-PROCESSING INNOVATION
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