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International Journal of Minerals,Metallurgy and Materials 2020年第11期27卷 1482-1488页

作者： Jing-qun Yin zhi-qiang Zou Jun Tian Institute of Applied Chemistry Jiangxi Academy of SciencesNanchang 330029China School of Resource and Environmental Engineering Jiangxi University of Science and TechnologyGanzhou 341000China

Crystalline rare-earth(RE)carbonates having large particle size were prepared from the lixivium of weathered crust elution-deposited rare-earth ores using the precipitation method with ammonium bicarbonate as the *** chemical composition was studied using elemental and thermogravimetric analyses(TGA),and their structure and morphology were characterized using Fourier transform infrared(FTIR)spectroscopy,X-ray diffraction(XRD),and scanning electron microscopy(SEM).The results demonstrate that the crystalline rareearth carbonate is a hydrated basic carbonate or oxycarbonate and not astable intermediate carbonate in the process of thermal *** particle size of crystalline rare-earth carbonates with large particle size is in the range of 50–200μ*** an RE2O3 content of up to 95wt%,the quality of crystalline rare-earth carbonates is higher compared to the Chinese National Standard(GB/T 28882–2012).The quality of the product is superior to the Chinese National Standard.

关键词： rare-earth ores precipitation crystalline rare-earth carbonate large particle size

Research on High-Availability of Softswitch System

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The Journal of China Universities of Posts and Telecommunications 2006年第2期13卷 50-53页

作者： LOU zhi-qiang LIAO Ning Beijing Telestar Telecommunications Technology Institute Beijing University of Posts and Telecommunications Beijing 100876 P.R. China School of Telecommunication Engineering Beijing University of Posts and Telecommunications Beijing 100876 P.R. China

Since softswitch is the kernel of the Next Generation Network （NGN）, it is practically significant to improve the availability of the softswitch system. This paper expatiates upon the methods of realizing the high-availability of softswitch system. It gives the methods from a multi-level viewpoint ： software-level high-availability design, platformlevel high-availability of softswitch kernel components, network-level high-availability. Additonally, it gives certain analysis on obtaining network high-availability.

关键词： softswitch high-availability single-distributor multi-processors cluster multi-level monitor

Late-model Ionic Clusters of KNO_3 and Their Configurations

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Chemical Research in Chinese Universities 2005年第5期21卷 587-591页

作者： SHI Lei YANG zhi LIU zhi-qiang LIU Shu-ying School of Public Health Jilin University Changchun 130021 P. R. China Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 P. R. China

Late-model ionic clusters of KNO3 were formed under the conditions of electrospray ionization. A series of peaks of the ionic clusters could be observed in the electrospray ionization mass spectra（ESIMS）. The general formulae of the ionic clusters were deduced to be K^ ＋（ KNO3 ） m and NO3^-（ KNO3 ）m. By referring to the crystal structure of KNOs , the possible configurations of these new typical ionic clusters were speculated based on the calculated data by means of the Gaussian-94^x computer program.

关键词： Cluster KNO3 Configuration Gaussian-94^* computer program

A review of geometric calibration for different 3-D X-ray imaging systems

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Nuclear Science and Techniques 2016年第3期27卷 194-204页

作者： Yang,Yao Li,Liang Chen,zhi-qiang Department of Engineering Physics Tsinghua UniversityBeijing 100084China Key Laboratory of Particle and Radiation Imaging(Tsinghua University) Ministry of EducationBeijing 100084China

A precise knowledge of geometry is always pivotal to a 3-D X-ray imaging system,such as computed tomography(CT),digital X-ray tomosynthesis,and computed *** get an accurate and reliable reconstruction image,exact knowledge of geometry is ***,geometric calibration has become a necessary step after completing CT system *** geometric calibration methods have been reported with the fast development of 3-D X-ray imaging *** these methods,different measuring methods,calibration phantoms or markers,and calculation algorithms were involved with their respective advantages and *** paper reviews the history and current state of geometric calibration methods for different3-D X-ray imaging *** calibration algorithms are presented and summarized,followed by our discussion and outlook.

关键词： X射线成像系统几何校正三维计算机断层扫描计算机层析成像 X射线成像技术综述校准方法

Mode Conversion and Diffraction of Guided Optical Waves from Magnetostatic Waves under Inclined Bias Magnetic Field

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Communications in Theoretical Physics 2001年第10期36卷 497-502页

作者： WU Bao-Jian LIU Gong-qiang ZOU zhi-qiang Department of Applied Physics Shanghai Jiao Tong University Shanghai 200030 China Department of Applied Physics Shanghai Jiao Tong University Shanghai 200030 China Department of Applied Physics Shanghai Jiao Tong University Shanghai 200030 China

The noncollinear interaction of guided optical waves with magnetostatic waves under inclined bias magnetic field is theoretically studied in detail. Similar approach can also be applied to the collinear interaction. Calculation results indicate that the diffraction efficiency (DE) in magnitude is equal to the mode-conversion efficiency (MCE) under vertical bias magnetic field, but they differ greatly under inclined bias magnetic field. By comparison to the case of vertical magnetization, the DE or the MCE can be greatly increased under inclined magnetic field. The characteristic of the DE curves obtained is basically in agreement with the experimental result.

关键词： guided optical wave, magnetostatic wave, mode conversion, diffraction efficiency

Soil Fertility Self-development Under Ecological Restoration in the Zhuxi Watershed in the Red Soil Hilly Region of China

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Journal of Mountain Science 2014年第5期11卷 1231-1241页

作者： BAI Li-yue CHEN zhi-qiang CHEN zhi-biao College of Geographical Sciences Fujian Normal University Institute of Agriculture Regional Planning of Fujian Province

Current methods that utilize simple data or models to judge whether soil fertility can selfdevelop are not sufficiently rigorous. A new framework has been set up using catastrophe theory, laboratory experiment, field work, and 3S(Geographic information system, Global positioning system, and Remote sensing) to explore soil fertility catastrophe under ecological restoration, discriminate whether soil fertility can self-develop, and propose adjustment of ecological restoration measures in the Zhuxi watershed of Changting County, Fujian Province, China, which is a typical representative of the red soil hilly region of China. The results show that: 1) the soil fertility is obviously improved through the four ecological restoration measures, which impels soil fertility catastrophe. Among 89 soil samples, catastrophic soil samples and stable soil samples account for 26(29.21%) and 63(70.79%) of the samples, respectively. The four ecological restoration measures are listed in the order lowquality forest improvement > arbor–bush–herb mixed plantation > orchard improvement > closing measures according to the proportions of catastrophic soil samples. A typical soil sample in Bashilihe that can self-develop is selected as the criterion to judge the upper lobe and lower lobe of soil fertility in the process surface of the Cusp catastrophe model. Twenty-six(29.21%) were in the middle lobe, 10(11.24%) were in the upper lobe, and 53(70.79%) were in the lower lobe. The catastrophic direction of 26 catastrophic soil samples is to the upper lobe according to soil and water loss change as well as fieldwork. There is a significant positive correlation of Δ with soil and water loss change, and the lower soil and water loss relates to higher catastrophic probability. 2) Soil fertility self-development could be regionalized as "Soil fertility can self-develop" whose area was 12.74 km2(28.33%) distributed mainly in the leftmost and rightmost parts, "Soil fertility tends to self-develop" who

关键词： Soil fertility Catastrophe Ecological restoration Red soil hilly region

A modified stratified model for the 3C 273 jet

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Chinese Journal of Astronomy and Astrophysics 2009年第5期9卷 520-528页

作者： Wen-Po Liu zhi-qiang Shen Key Laboratory for Research in Galaxies and Cosmology Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai 200030 China Graduate School of Chinese Academy of Sciences Beijing 100049 China

We present a modified stratified jet model to interpret the observed spectral energy distributions of knots in the 3C 273 jet. Based on the hypothesis of the single index of the particle energy spectrum at injection and identical emission processes among all the knots, the observed difference of spectral shape among different 3C 273 knots can be understood as a manifestation of the deviation of the equivalent Doppler factor of stratified emission regions in an individual knot from a characteristic one. The summed spectral energy distributions of all ten knots in the 3C 273 jet can be well fitted by two components; a low-energy component （radio to optical） dominated by synchrotron radiation and a high- energy component （UV, X-ray and γ-ray） dominated by inverse Compton scattering of the cosmic microwave background. This gives a consistent spectral index of α = 0.88 （Sv ∝ v^-α） and a characteristic Doppler factor of 7.4. Assuming the average of the summed spectrum as the characteristic spectrum of each knot in the 3C 273 jet, we further get a distribution of Doppler factors. We discuss the possible implications of these results for the physical properties in the 3C 273 jet. Future GeV observations with GLAST could separate the 7-ray emission of 3C 273 from the large scale jet and the small scale jet （i.e. the core） through measuring the GeV spectrum.

关键词： galaxies active -- galaxies individual (3C 273) -- galaxies jets -- radia- tion mechanisms non-thermal

Mixtures of Semiparametric Varying Coefficient Models for Longitudinal Data with Nonignorable Dropout

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Acta Mathematicae Applicatae Sinica 2010年第1期26卷 125-132页

作者： zhi-qiang Li Liu-gen Xue College of Sciences Beijing University of Chemical Technology Beijing 100029 China College of Applied Sciences Beijing University of Technology Beijing 100022 China

Informative dropout often arise in longitudinal data. In this paper we propose a mixture model in which the responses follow a semiparametric varying coefficient random effects model and some of the regression coefficients depend on the dropout time in a non-parametric way. The local linear version of the profile-kernel method is used to estimate the parameters of the model. The proposed estimators are shown to be consistent and asymptotically normal, and the finite performance of the estimators is evaluated by numerical simulation.

关键词： Nonignorable dropout, Estimating equation, Profile-kernel, Local linear estimation, Longitudinal data Semiparametric varying coefficient

Subcarrier assignment considering path loss for multiuser OFDM systems with proportional fairness

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The Journal of China Universities of Posts and Telecommunications 2008年第2期15卷 12-17,25页

作者： XU Wen-jun HE zhi-qiang School of Information Engineering Beijing University of Posts andTelecommunications Beijing 100876 China

This article studies downlink subcarrier assignment problem to maximize rate-sum capacity subject to total power and proportional rate constraints in orthogonal frequency division multiplexing （OFDM） systems. Previous algorithms assume that the initial power is equally distributed over all subcarriers. The presence of path loss makes the assumption not correct any more. This article proposes a novel subcarrier assignment algorithm which makes full use of path loss and rate proportionality information to improve rate-sum capacity. The proposed algorithm determines optimal initial power allocation according to path losses and rate proportionalities of different users, assigns subcarriers to users in a greedy fashion, and then exchanges subcarfiers between users to obtain fairer rate distribution. Simulation results show that the proposed algorithm approximately achieves double the capacity of static assignment schemes, such as fixed frequency band approach, and obtains better performance than previous subcarrier assignment algorithms in the presence of different path losses and proportional rate requirements..

关键词： OFDM subcarrier assignment path loss

冠状动脉旋磨术对老年冠心病合并冠状动脉钙化患者的疗效及安全性分析

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心血管病防治知识（学术版） 2023年第20期13卷 32-34,39页

作者：罗远林徐燕梅谭志强李林岭周学锋杨锦龙四川省乐山市人民医院四川乐山614000 乐山职业技术学院医学系四川乐山614000

目的探讨老年冠心病合并冠状动脉钙化患者采用冠状动脉旋磨术的治疗效果。方法选取该院2021年1-12月收治的老年冠心病合并冠状动脉钙化患者104例,根据是否行冠状动脉旋磨术分为对照组(54例,采用常规介入治疗)、观察组(50例,在常规介入... 详细信息

目的探讨老年冠心病合并冠状动脉钙化患者采用冠状动脉旋磨术的治疗效果。方法选取该院2021年1-12月收治的老年冠心病合并冠状动脉钙化患者104例,根据是否行冠状动脉旋磨术分为对照组(54例,采用常规介入治疗)、观察组(50例,在常规介入基础上行冠状动脉旋磨术),比较两组患者治疗前后心脏射血分数(EF)、靶血管管腔直径、术后并发症情况以及术后12个月主要不良心血管事件(MACE)发生率。结果两组患者吸烟史、高血压、糖尿病、术前心脏射血分数、术前靶血管管腔直径比较,差异均无统计学意义(P>0.05),术后观察组患者心脏射血分数、靶血管管腔直径明显优于对照组(P0.05);术后12个月两组患者MACE事件(心源性死亡、非致死性心梗、支架内血栓形成、靶血管血运重建)发生率无明显差异(P>0.05)。结论针对老年冠心病合冠状动脉钙化患者,冠状动脉旋磨术治疗能有效改善患者冠状动脉狭窄和心功能,安全性较高,值得临床广泛应用。

关键词：冠状动脉旋磨术冠状动脉钙化老年疗效安全性