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Main deposit styles and associated tectonics of the West Junggar region,NW China

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Geoscience Frontiers 2015年第2期6卷 175-190页

作者： Ping shen Hongdi Pan yuanchao shen Yuhong Yan Shihua zhong Key Laboratory of Mineral Resources Institute of Geology and Geophysics Chinese Academy of Sciences College of Earth Sciences Chang’an University

The West Junggar region, located in the loci of the Central Asian Orogenic Belt, is a highly endowed metallogenic province with 〉100 tonnes Au, 〉0.7 Mt Cu, 〉0.3 Mt Mo, and 〉2.3 Mt chromite as well as significant amounts of Be and U. The West Junggar region has three metallogenic belts distributed systematically from north to south：（1） late Paleozoic Saur Au-Cu belt; （2） early Paleozoic Xiemisitai- Sharburt Be-U-Cu-Zn belt; （3） late Paleozoic Barluk-Kelamay Au-Cu-Mo-Cr belt. These belts host a number of deposits belonging to at least eight economically important styles, including epithermal Au, granite-related Be-U, volcanogenic massive sulfide （VMS） Cu-Zn, podiform chromite, porphyry Cu, hydrothermal quartz vein Au, porphyry-greisen Mo（-W）, and orogenic Au. These deposit styles are associated with the tectonics prevalent during their formation. Five tectonic-mineralized epochs can be recognized：（1） Ordovician subduction-related VMS Cu-Zn deposit; （2） Devonian ophiolite-related podiform chromite deposit; （3） early Carboniferous subductionrelated epithermal Au and porphyry Cu deposits; （4） late Carboniferous subduction-related granite-related Be-U, porphyry Cu, and hydrothermal quartz vein Au deposits; and （5） late Carboniferous to early Permian subduction-related por- phyry-greisen Mo（-W） and orogenic Au deposits.

关键词： Mineral deposit styles Metallogenic belts Tectonic-mineralized epoch West Jonggar Xinjiang

New lignan glycosides from Glehnia littoralis

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Chinese Chemical Letters 2008年第12期19卷 1459-1461页

作者： Wei Xue Kong zhong yuan School of Traditional Chinese Materia Medica Shenyang Pharmaceutical University Shenyang 110016 China

From the roots ethanol extract of Glehnia littoralis, two new lignan glycosides, named glehlinoside E （1） and F （2）, were obtained. Their structures were determined to be （-）-secoisolariciresinol 4-O-β-D-（6-O-feruloyl） glucopyranoside （1） and （-）- secoisolariciresinol 4-O-f-β-D-（6-O-caffeloyl） glucopyranoside （2） by analysis of their spectral data, respectively.

关键词： Glehnia littoralis Lignan glycoside Glehlinoside E and F

A New Triterpenoid Saponin from Codonopsis lanceolata

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Chinese Chemical Letters 2006年第11期17卷 1460-1462页

作者： zhong yuan Zhi Min LIANG School of Traditional Chinese Materia Medica Shenyang Pharmaceutical University Shenyang 110016

A new triterpenoid saponin, named codonolaside （1） was isolated from the root of Codonopsis lanceolata. Its structure was determined by analysis of its spectral and chemical data.

关键词： Codonopsis lanceolata triterpenoid saponin codonolaside.

Conformists and Contrarians in a Kuramoto Model with Uniformly Distributed Natural Frequencies

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Communications in Theoretical Physics 2013年第6期59卷 684-688页

作者： yuan Di YANG Jun-zhong School of Science Beijing University of Posts and Telecommunications Beijing 100876 China School of Physics and Electrical Engineering Anyang Normal University Anyang 455000 China

A generalization of the Kuramoto model in which oscillators are coupled to the mean field with random signs is investigated in this work. We focus on a situation in which the natural frequencies of oscillators follow a uniform probability density. By numerically simulating the model, we find that the model supports a modulated travelling wave state except for already reported 7r state and travelling wave state in the one with natural frequencies following Lorenztian probability density or a delta function. The dependence of the observed dynamics on the parameters of the model is explored and we find that the onset of synchronization in the model displays a non-monotonic dependence on both positive and negative coupling strength.

关键词： Kuramoto model modulated travelling wave state conformist contrarian

Flow properties of three fuel powders

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Particuology 2012年第4期10卷 438-443页

作者： Pan Chen Zhulin yuan Xianglin shen yuanyuan Zhang School of Energy and Environment Southeast UniversityNanjing 210096China

Flow and physical properties were measured for three fuel powders： sawdust, brown coal and hard coal. Besides physical properties, e.g., particle size, bulk density and moisture content, flowability was investigated using the standard shear testing technique of the Jenike shear cell. Flow functions of the three powders used for characterization of bulk flow and design of hoppers were determined, and then compared and discussed. The flow functions of the three powders are located in different regions： while brown coal and hard coal were classified respectively as easy flowing and cohesive material, sawdust was found in regions varying from cohesive to easy fowing at low consolidation stress. The measured effective angle of internal friction and angle of wall friction were 55° and 31.4° for sawdust; 36.2° and 26° for brown coal; and 43.3° and 27.8° for hard coal. Using the measured powder flow properties, Jenike＇s procedure was then followed to estimate and compare the critical hopper dimensions for mass flow of the three powders.

关键词： Powder flow functionEffective angle of internal frictionAngle of wall frictionJenike shear cellParticle distributionMoisture content

Defects activation in CoFe-based metallic glasses during creep deformation

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Journal of Materials Science & Technology 2021年第10期69卷 42-47页

作者： Zhuwei Lv Chenchen yuan Haibo Ke Baolong shen School of Materials Science and Engineering Jiangsu Key Laboratory for Advanced Metallic MaterialsSoutheast UniversityNanjing211189China Songshan Lake Materials Laboratory Dongguan523808China

Maxwell-Voigt model with two Kelvin units and one Maxwell unit was utilized to analyze the microalloying effect of Cu on the creep behavior of CoFe-based metallic glasses at different loading *** defect activation during creep deformation was detected by the relaxation time spectrum based on this *** defect,with respect to a short relaxation time in relaxation spectra,intends to be activated at a quasi-static loading mode in the alloy with 0.5 at.%Cu *** further increasing loading rates,more defects with a large size were provoked activated at both hard and soft regions in the Cu-containing sample.A softening with the reduction of elastic modulus and hardness about 10%and 15%,respectively,was also observed in the Cu-doped *** is consistent with the pronounced viscoplastic deformation of this alloy along with the decrease of *** work provides a microscopic insight into structural evolution during creep deformation in a Cu-doped metallic glass,which might help for understanding the plastic deformation of metallic glasses upon a minor addition.

关键词： Plasticity Creep Disordered Structure Metallic glasses

Growth process,defects,and dopants of bulk β-Ga_(2)O_(3) semiconductor single crystals

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China Foundry 2024年第5期21卷 491-506页

作者： Yan-shen Wang Ming-zhi Zhu yuan Liu School of Materials Science and Engineering Tsinghua UniversityBeijing 100084China Key Laboratory for Advanced Materials Processing Technology(Ministry of Education) Beijing 100084China

β-gallium oxide(β-Ga2O3),as the typical representative of the fourth generation of semiconductors,has attracted increasing attention owing to its ultra-wide bandgap,superior optical properties,and excellent tolerance to high temperature and *** to the single crystals of other semiconductors,high-quality and large-size β-Ga_(2)O_(3) single crystals can be grown with low-cost melting methods,making them highly *** this review,the growth process,defects,and dopants ofβ-Ga_(2)O_(3) are primarily ***,the growth process(e.g.,decomposition,crucible corrosion,spiral growth,and development)ofβ-Ga_(2)O_(3) single crystals are summarized and compared in ***,the defects of β-Ga_(2)O_(3) single crystals and the influence of defects on Schottky barrier diode(SBD)devices are emphatically ***,the influences of impurities and intrinsic defects on the electronic and optical properties ofβ-Ga_(2)O_(3) are also briefly *** this comprehensive analysis,the article offers a concise summary of the current state,challenges and prospects ofβ-Ga_(2)O_(3) single crystals.

关键词： β-Ga_(2)O_(3) single-crystal growth defects dopants semiconductor

Study on the effect of thermal deformation on the liquid seal of high-temperature molten salt pump in molten salt reactor

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Nuclear Science and Techniques 2023年第2期34卷 128-138页

作者： Xing‑Chao shen yuan Fu Jian‑Yu Zhang Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China

The high-temperature molten salt pump is the core equipment in a molten salt reactor that drives the flow of the molten salt *** stability is key to the continuous and reliable operation of the molten salt pump,and the liquid seal at the wear ring can affect the dynamic characteristics of the rotor *** the molten salt pump is operated in the hightemperature molten salt medium,thermal deformation of the submerged parts inevitably occurs,changing clearance between the stator and rotor,affecting the leakage and dynamic characteristics of the *** this study,the seal leakage,seal dynamic characteristics,and rotor system dynamic characteristics are simulated and analyzed using finite element simulation software based on two cases of considering the effect of seal thermal deformation effect or *** results show a significant difference in the leakage characteristics and dynamic characteristics of the seal obtained by considering the effect of seal thermal deformation and neglecting the effect of thermal *** leakage flow rate decreases,and the first-order critical speed of the seal-bearing-rotor system decrease after considering the seal’s thermal deformation.

关键词： High-temperature molten salt pump Seal thermal deformation Leakage characteristics Seal dynamic characteristics Critical speed

Online identification of time-varying dynamical systems for industrial robots based on sparse Bayesian learning

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Science China(Technological Sciences) 2022年第2期65卷 386-395页

作者： shen Tan DONG YunLong HE DingXin yuan Ye School of Artificial Intelligence and Automation Huazhong University of Science and TechnologyWuhan 430074China

Nowadays, industrial robots have been widely used in manufacturing, healthcare, packaging, and more. Choosing robots in these applications mainly attributes to their repeatability and precision. However, prolonged and loaded operations can deteriorate the accuracy and efficiency of industrial robots due to the unavoidable accumulated kinematical and dynamical errors. This paper resolves these aforementioned issues by proposing an online time-varying sparse Bayesian learning(SBL) method to identify dynamical systems of robots in real-time. The identification of dynamical systems for industrial robots is cast as a sparse linear regression problem. By constructing the dictionary matrix, the parameters of the robot dynamics are effectively estimated via a re-weighted1-minimization algorithm. Online recursive methods are integrated into SBL to achieve real-time system identification. By including sparsity and promoting online learning, the proposed method can handle time-varying dynamical systems and therefore improve operational stability and accuracy. Experimental results on both simulated and real selective compliance assembly robot arm(SCARA) robots have demonstrated the effectiveness of the proposed method for industrial robots.

关键词： industrial robots sparse Bayesian learning online identification