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The Zoulang Nanshan Caledonian Subduct ion Complex in the Northern qilian Mountains and Its Dynamics

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Acta Geologica Sinica(English Edition) 1994年第3期68卷 225-241页

作者： Xu Zhiqin, Xu Huifen, Zhang Jianxin, Li Haibing, zhu Zhizhi, qu Jingchuan,Institute of Geology, Chinese Academy of Geological Sciences, BeijingChen Daizhang, Chen Jinlu, China University of Geosciences, Beijingand Yang KaichunNo. 2 q ilian Geological Party, Bureau of Geology and Mineral Resources of q inghai Province, q ilian County, q inghai Chinese Academy of Geological Sciences Beijing China

The front of the Zoulang Nanshan Caledonian volcanic island arc zone in the northern qilian Mountains is a forearc accretionary terrane, composed of multiple accretionary volcanic island arcs, flysch accretionary wedges,high-pressure metamorphosed detachment zones and remnants of ophiolites. It resulted from the northeastward subduction of the Early Palaeozoic qilan oceanic crust beneath the Alxa block. High-pressure metamorphism, which occurred during the subduction, progressed through three stages: the initial stage of medium T-high P,the main stage of temperature decrease and pressure increase, and the lag stage of pressure decrease and temperature increase. Finally the paper presents a retrotrench subduction dynamic model indicative of northward subduction of the central qilian block and southward accretion of the Alxa block during the period of 450-500 Ma.

关键词： subduction complex accretionary terrane multiple structure retrotrench subduction dynamics

A FAMILY OF THE LOCAL CONVERGENCE OF THE IMPROVED SECANT METHODS FOR NONLINEAR EqUALITY CONSTRAINED OPTIMIZATION SUBJECT TO BOUNDS ON VARIABLES

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Journal of Systems Science & Complexity 2014年第2期27卷 307-326页

作者： ZHANG Yong zhu Detong School of Mathematics and Physics Changzhou University Mathematics and Science College Shanghai Normal University

This paper studies a family of the local convergence of the improved secant methods for solving the nonlinear equality constrained optimization subject to bounds on variables. The Hessian of the Lagrangian is approximated using the DFP or the BFGS secant updates. The improved secant methods are used to generate a search direction. Combining with a suitable step size, each iterate switches to trial step of strict interior feasibility. when the Hessian is only positive definite in an affine null subspace, one shows that the algorithms generate the sequences converging q-linearly and two-step q-superlinearly. Yhrthermore, under some suitable assumptions, some sequences generated by the algorithms converge locally one-step q-superlinearly. Finally, some numerical results are presented to illustrate the effectiveness of the proposed algorithms.

关键词： Affine scaling local convergence secant methods second order correction.

Microwave dielectric properties and microstructure of a new kind Eu-based Eu(Mg_(0.5)Ti_(0.5))O_3 ceramic

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Rare Metals 2018年第11期37卷 913-918页

作者： Tao Shi Jing zhu National Center for Electron Microscopy in Beijing Tsinghua University School of Materials Science and Engineering Tsinghua University The State Key Laboratory of New Ceramics and Fine Processing Tsinghua University Laboratory of Advanced Materials Tsinghua University

A new Eu-based microwave dielectric ceramic,Eu(MgTi)O(EMT for short), was prepared through conventional solid-state reactions. The EMT ceramics were well densified at 1425 ℃ and exhibit good microwave dielectric properties with permittivity of 23.92, high quality factor(q*f) of 66,957 GHz at 8.93 GHz and relatively low-temperature coefficient of resonant frequency of-20.3 10/K. Additionally, the variations of dielectric constants among Ln(MgTi)O(Ln represents rare earth elements, LMT) compounds were analyzed. Ionic radii of Ln, associated with the tolerance factors of the perovskite structure of LMT, were investigated to be the key factor to influence the permittivity. These results indicate that EMT ceramics might be one of the promising candidates as microwave resonators.

关键词： Microwave dielectrics Eu(Mg_(0.5)Ti_(0.5))O_3 Complex perovskite Solid-state reactions

Compensation of Unbalanced Impedance of Asymmetric wind Power PMSG Compensated by External Circuits in Series

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CES Transactions on Electrical Machines and Systems 2017年第2期1卷 180-188页

作者： Yashan Hu Z.q.zhu Milijana Odavic Sheffield Siemens wind Power Research Centre and Department of Electronic and Electrical Engineering University of SheffieldMappin StreetSheffield S13JDUK Royal Academy of Engineering

The unbalanced impedance of the asymmetric 3-phase wind power permanent magnet synchronous generator(PMSG)compensated by external circuits in series with the 3-phase windings is investigated in this *** asymmetric impedance includes the unbalanced resistances,unbalanced self-inductances,and unbalanced mutual *** the perspective of the second harmonic inductances in dq-frame and from the perspective of the second harmonic power,it is theoretically demonstrated that the original asymmetric 3-phase system with asymmetric impedance can be modified to a balanced system by external circuits consisting of resistances and ***,the second harmonic power and DC bus voltage due to the asymmetries can be suppressed naturally without any software *** feasibility of this compensation method is validated by elaborate experiments at different speeds and under different load condition,although the effectiveness might be slightly affected by the non-linearity of the compensation inductance in practice.

关键词： Asymmetry compensation in series second harmonic DC bus voltage unbalance compensation unbalanced impedance

STRUCTURAL TRANSFORMATION INDUCED BY MECHANICALLY DRIVEN ALLOYING AND SUBSEqUENT MAGNETIC PROPERLIESOF THE Fe-Cu SYSTEM

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Acta Metallurgica Sinica(English Letters) 1998年第2期11卷 128-136页

作者： Y.Z.Yang Y.HLuo q.S.Li Y.L.zhu X.M.Ma Y.D.Dong Y.Z.Chuang Guangdong Univ of Technology Guangzhou China

The structural transformation in Fe-Cu powder induced by mechanically driven alloying has been monitored by the lattice constant measurements and Mossbauer spectroscopy. For the samples with Cu higher than 75at.% Mossbauer the spectra show a broad paramagnetic doublet; for samples with 50 and 60at.%Cu a new broad ferromagnetic sextet; for those with less than 30at.%Cu similar to those of α-Fe. The main peaks of the hyperfine field distribution significantly broaden and shift to a lower position with increasing Cu content due to the complex environments of iron atoms in the solid solutions and the reduction in the nearest neighbor Fe of a cental Fe atom, respectively. The saturation magnetization of Fe-Cu alloys monotonously decreases with Cu content. The complex composition dependence of coercive field for the milled samples is discussed with respect to the solid dissolution, grain size, interfacial state etc.. The increase of lattice constants with the solute content in the two terminal solid solutions has been explained by the volume-size factor theory or magnetovolume effect.

关键词： mechanical alloying Mossbauer effect Fe-Cu alloy magnetic measurement

Recent Advances in Variable Flux Memory Machines for Traction Applications: A Review

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CES Transactions on Electrical Machines and Systems 2018年第1期2卷 34-50页

作者： Hui Yang Heyun Lin Z.q.zhu School of Electrical Engineering Southeast UniversityNanjingP.R.China Department of Electronic and Electrical Engineering University of SheffieldSheffieldU.K

This paper overviews the recent advances in variable flux memory machines(VFMMs)for traction applications with particular reference to newly emerged machine topologies and related control *** to the use of flux memorable low coercive force(LCF)magnets,the air-gap flux of VFMM can be flexibly varied via a magnetizing current ***,the copper loss associated with the flux weakening current and high-speed iron loss can be significantly reduced,and hence high efficiency can be achieved over a wide speed and torque/power *** merits make VFMM potentially attractive for electric vehicle(EV)*** novel VFMMs are reviewed with particular reference to their topologies,working principle,characteristics and related control *** order to tackle the drawbacks in the existing VFMMs,some new designs are introduced for performance ***,the electromagnetic characteristics of an exemplified EV-scaled switched flux memory machine and various benchmark traction machine choices,such as induction machine,synchronous reluctance machines,as well as commercially available Prius 2010 interior permanent magnet(IPM)machine are ***,the key challenges and development trends of VFMM are highlighted,respectively.

关键词： AC-magnetized DC-magnetized electrical machines electric vehicles hybrid permanent magnet(PM) memory machine variable flux

Recent Development of Reluctance Machines with Different winding Configurations,Excitation Methods,and Machine Structures

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CES Transactions on Electrical Machines and Systems 2018年第1期2卷 82-92页

作者： X.Y.Ma G.J.Li G.w.Jewell Z.q.zhu Department of Electronic&Electrical Engineering The University of SheffieldSheffieldUK

This paper reviews the performances of some newly developed reluctance machines with different winding configurations,excitation methods,stator and rotor structures,and slot/pole number *** the double layer conventional(DLC-),double layer mutually-coupled(DLMC),single layer conventional(SLC-),and single layer mutually-coupled(SLMC-),as well as fully-pitched(FP)winding configurations have been considered for both rectangular wave and sinewave *** conduction angles such as unipolar􀫚120°elec.,unipolar/bipolar􀫚180°elec.,bipolar􀫛240°*** bipolar􀫜360°*** been adopted and the most appropriate conduction angles have been obtained for the SRMs with different winding *** addition,with appropriate conduction angles,the 12-slot/14-pole SRMs with modular stator structure is found to produce similar average torque,but lower torque ripple and iron loss when compared to non-modular 12-slot/8-pole *** sinewave excitation,the doubly salient synchronous reluctance machines with the DLMC winding can produce the highest average torque at high currents and achieve the highest peak efficiency as *** order to compare with the conventional synchronous reluctance machines(SynRMs)having flux barriers inside the rotor,the appropriate rotor topologies to obtain the maximum average torque have been investigated for different winding configurations and slot/pole number ***,some prototypes have been built with different winding configurations,stator structures,and slot/pole combinations to validate the predictions.

关键词： Double/single layer windings excitation methods fully/short-pitched mutually coupled modular machines switched/synchronous reluctance machines

Modularity Techniques in High Performance Permanent Magnet Machines and Applications

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CES Transactions on Electrical Machines and Systems 2018年第1期2卷 93-103页

作者： Z.q.zhu Y.X.Li University of Sheffield UK

This paper reviews the modularity techniques in the stator manufacture of permanent magnet machines for different *** basic concepts of modular machines are firstly *** machines for several typical applications are then described in details,including domestic appliances,automobiles and electric vehicles,more electric aircrafts and civic applications,wind power generators,***,the influence of manufacture tolerance gaps and flux barriers on the electromagnetic performance is discussed.

关键词： Domestic appliance electric vehicle(EV) modular machine more electric aircraft permanent magnet wind power generator

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高龄女性卵子颗粒细胞转录组的数据分析

中国组织工程研究 2025年第19期29卷 4069-4075页

作者：秦立峰王加强朱伶东北农业大学生命科学学院黑龙江省哈尔滨市150030 重庆市妇幼保健院人类胚胎工程重庆市重点实验室重庆市400013

背景:颗粒细胞的状态很大程度上影响卵母细胞的质量。随着高龄女性在辅助生殖中占比不断增多,为了能更好地评估卵母细胞的质量,此研究在转录水平对不同年龄段患者来源的颗粒细胞进行了检测。目的:探究低龄和高龄患者颗粒细胞mRNA及长链... 详细信息

背景:颗粒细胞的状态很大程度上影响卵母细胞的质量。随着高龄女性在辅助生殖中占比不断增多,为了能更好地评估卵母细胞的质量,此研究在转录水平对不同年龄段患者来源的颗粒细胞进行了检测。目的:探究低龄和高龄患者颗粒细胞mRNA及长链非编码RNA表达变化。方法:在辅助生殖治疗周期中收集患者取卵时获得的废弃卵丘颗粒细胞,其中低龄组患者年龄为25-35周岁,高龄组患者年龄为38-45周岁。对低龄和高龄女性颗粒细胞进行RNA-seq分析,每组3个重复。结果与结论:①RNA-seq分析结果显示,样本平均测序量超过14 G,质控后的数据质量q30超过93%,数据平均比对率为98.4%,表明数据质量较好;②主成分分析及相关性分析结果显示高龄组和低龄组样本间基因表达水平具有明显差异;③差异分析结果显示,相对于低龄组,高龄组颗粒细胞中共有410个差异表达的mRNA,其中上调基因167个,下调基因243个,GO分析结果显示下调基因主要富集到胞吐作用调节、激素代谢过程等,GSEA分析结果显示高龄组颗粒细胞中与分泌相关的通路表达下调;④相对于低龄组,高龄组共检测到662个差异表达的长链非编码RNA,这部分长链非编码RNA直接调控的蛋白质编码基因为1772个,其中与差异表达基因交集59个。结果表明:高龄组颗粒细胞中与分泌相关的基因及通路表达下调,从而影响卵母细胞质量,同时这些表达下调的基因受到长链非编码RNA调控,因此长链非编码RNA的表达可能与年龄有关。

关键词：年龄颗粒细胞卵母细胞全转录组差异基因长链非编码基因