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Charge Transfer for Reactions of Sc^(3+) with N_(2) and H_(2) at Electron-volt Energy

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Chinese Physics Letters 2001年第4期18卷 528-530页

作者： JIANG Yu-Rong NIE Zong-Xiu li jiao-mei GAO Ke-lin Laboratory of Magnetic Resonance and Atomic and Molecular Physics Wuhan Institute of Physics and MathematicsChinese Academy of SciencesWuhan 430071

The charge transfer rate coefficients for reactions of Sc^(3+)with N_(2) and H_(2) have been measured at the mean collision energy of *** rate coefficients are derived from the decay rate of ion signals by using ion storage in a radio-frequency ion *** rate coefficients are 8.18(0.18)×10^(-10)cm^(3)·s^(-1) at Tequiv≈1.26×10^(4)K for Sc^(3+) with N_(2) and 1.44(0.39)×10^(-9)cm^(3)·s^(-1) at Tequiv>≈1.67×10^(3) K for Sc^(3+) with H_(2),*** results are comparable with the Langevin rate coefficients.

关键词： coefficients Electron H_

Observation of Hysteresis of the Ion Cloud Motion in an rf Trap

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Chinese Physics Letters 1997年第8期14卷 581-584页

作者： GAO Ke-lin LUO Xue-li ZHU Xi-wen YAN Min li jiao-mei Laboratory of Magnetic Resonance and Atomic and Molecular Physics Wuhan Institute of PhysicsChinese Academy of SciencesWuhan 430071

Variations of the hysteresis of the rf detection signals corresponding to the axial motion of an ion cloud in a Paul trap versus the detection voltage,operation parameters and number of ions have been *** features are explained by an extended pseudopotential model with an octupole potential correction and an effective potential from the ion cloud.

关键词： correction hysteresis Hyster

Effect of the Double Frequency of Trap Field in a Paul Trap

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Communications in Theoretical Physics 2001年第11期36卷 593-596页

作者： NIE Zong-Xiu FENG Mang li jiao-mei SHI Lei ZHU Xi-Wen GAO Ke-lin State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics Wuhan Institute of Physics and MathematicsThe Chinese Academy of SciencesWuhan 430071China

The effect of double frequency oftrap fieldφ=U-V1 cosΩt-V2 cos 2Ωt in a Paul trap can be described exactly by using a function series expansion to solve the corresponding Mathieu *** stability regions of a trapped ... 详细信息

关键词： double frequency trap field Paul trap

Quantitative computed tomography measurement of cross-sectional area of small pulmonary vessels in asthmatic patients

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Chinese Medical Journal 2019年第16期132卷 1903-1908页

作者： Juan Wang mei-jiao li Chun Chang Department of Respiratory and Critical Care Medicine Peking University Third HospitalBeijing 100191China Department of Radiology Peking University Third HospitalBeijing 100191China

Background: Cross-sectional area (CSA) for small pulmonary vessels is considered a parameter of pulmonary vessel alterations in patients with chronic obstructive pulmonary disease. This study was to evaluate the correlation of CSA with airflow obstruction parameters in asthma. Furthermore, we aimed to measure the difference in vascular alteration between asthma phenotypes and evaluate its relation with cytokine levels. Methods: We consecutively enrolled 20 adult asthmatic patients (13 women: age range, 26–80 years) and 20 healthy controls (8 women: age range, 23–61 years) from Peking University Third Hospital. Total CSA lice spiral computed tomography, and the percentage CSA linked immunosorbent assay was used to detect the expression of leptin, total immunoglobulin E, periostin, and transforming growth factor β1 in serum and matrix metalloproteinase 9 in induced sputum supernatant of asthmatic patients. The differences in %CSAlinical indexes and inflammatory cytokine levels. Results: Patients with asthma and controls did not differ in %CSAlimitatio

关键词： Asthma Computed tomography Airway remodeling

Experimental Determination(∼mHz)of the Ground-State Hyperfine Separation of Trapped ^(199)Hg^(+) in a Hyperbolic Paul Trap

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Chinese Physics Letters 2012年第12期29卷 70-73页

作者： HE Yue-Hong SHE Lei CHEN Yi-He YANG Yu-Na liU Hao li jiao-mei Key Laboratory of Atomic Frequency Standards(KLAFS) Wuhan Institute of Physics and MathematicsChinese Academy of SciencesWuhan 430071 State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics Wuhan Institute of Physics and MathematicsChinese Academy of SciencesWuhan 430071 Graduate School Chinese Academy of SciencesBeijing 100190

The Ramsey fringes on the ground-state hyperfine transition of ^(199)Hg^(+)(ΔF=1,ΔmF=0)ions trapped in a hyperbolic Paul trap are firstly observed with the method of time-separated oscillatory *** full width at half maximum of central Ramsey fringes is about 25 mHz and the corresponding quality factor Q of the line is greater than 10^(12) for the trapped ^(199)Hg^(+)microwave frequency *** hyperfine transition frequency shifted by magnetic field is also measured by the high-resolution Ramsey *** final result isΔνhfs=40507347997.3(0.5)Hz,which is corrected to zero magnetic field.

关键词： field. Ramsey

A Method of Measuring the Axial Secular Motion Temperature of Trapping Large Size Ion Clouds

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Chinese Physics Letters 2013年第3期30卷 18-21页

作者： YANG Yu-Na liU Hao HE Yue-Hong li Hai-Xia CHEN Yi-He SHE Lei CHEN liang li jiao-mei Key Laboratory of Atomic Frequency Standards(KLAFS) Wuhan Institute of Physics and MathematicsChinese Academy of SciencesWuhan 430071 State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics Wuhan Institute of Physics and MathematicsChinese Academy of SciencesWuhan 430071 University of the Chinese Academy of Sciences Beijing 100049

A large cloud of ^(40)Ca^(+) is successfully trapped and manipulated in a linear ion *** axial length of the ion cloud is measured under a series of end-cap *** propose a method of measuring the axial secular motion temperature of the ion cloud by analyzing its image on an electron-multiplying *** method is based on the Boltzmann equation that the axial density distribution of ions at secular motion temperature T *** axial secular motion temperature of the ion cloud is also obtained by measuring the Doppler broadened line *** the same trapping parameters,the axial secular motion temperature by analyzing the image of ion cloud is 840 K and by fitting the experimental resonance line profile is 700 K.

关键词： axial trapping fitting

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面向网络数据管理的并行查询处理

计算机工程与应用 2007年第30期43卷 5-10页

作者：王勇焦丽梅国家智能计算机研究开发中心北京100080 中国科学院计算技术研究所北京100080 中国科学院研究生院北京100039

随着互联网的迅猛发展,监控网络的所产生的海量数据对查询处理提出挑战。根据数据明显分为大量的事件数据和少量、稳定的配置数据的特点,提出了一种基于单机DBMS的并行查询处理方法。从关系代数的角度,将任意查询分解成对水平数据分区... 详细信息

随着互联网的迅猛发展,监控网络的所产生的海量数据对查询处理提出挑战。根据数据明显分为大量的事件数据和少量、稳定的配置数据的特点,提出了一种基于单机DBMS的并行查询处理方法。从关系代数的角度,将任意查询分解成对水平数据分区的子查询和汇总中间结果的后处理查询。借助DBMS提供的数据库链路,在不改动DBMS的情况下,方便地构造查询处理器。用真实负载的测试表明:在中间结果集不很大的情况下,能获得接近线性的扩展比。

关键词：网络数据管理水平分区查询处理扩展性

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基于关系结构的轻量级工作流引擎

计算机研究与发展 2001年第2期38卷 129-137页

作者：何清法李国杰焦丽梅刘力力中国科学院计算技术研究所北京100080

针对关键业务应用的开发离不开工作流技术的支持 ,通过对关键业务的实际开发需求的分析 ,在传统的关系数据库基础上 ,提出了一个适用于关键业务开发的基于关系结构的轻量级工作流引擎的框架结构 .此工作流模型由机构模型、信息模型和控... 详细信息

针对关键业务应用的开发离不开工作流技术的支持 ,通过对关键业务的实际开发需求的分析 ,在传统的关系数据库基础上 ,提出了一个适用于关键业务开发的基于关系结构的轻量级工作流引擎的框架结构 .此工作流模型由机构模型、信息模型和控制模型 3部分组成 .深入讨论了采用关系结构和轻量级理念来设计工作流引擎的原因 ,并详细地给出了相关的机构模型、信息模型和控制模型的设计原理以及具体的表示和实现方法 .其原型已经应用到实际的应用系统中 .实践证明。

关键词：轻量级工作流引擎关系结构软件开发计算机应用企业

Paul阱中囚禁的低能Ar^(2+)离子与Ar的电荷转移

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原子与分子物理学报 2007年第3期24卷 471-476页

作者：李俊陈亮李交美高克林中国科学院武汉物理与数学研究所波谱与离子分子物理国家重点实验室

在Paul阱中产生并选择囚禁了单一的Ar2+离子,得到低能Ar2+与Ar的电荷转移速率系数为5.84(0.677)×10-10cm3·s-1及其零氩气压强下的离子衰减速率为0.46 s-1,为下一步进行多电荷离子的亚稳态寿命研究提供了有价值的实验参考数据.

关键词： Paull离子阱选择囚禁低能多电荷离子电荷转移衰减速率