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Chinese Continental Blocks in Global Paleocontinental Reconstruction during Paleozoic and Mesozoic

Acta Geologica Sinica(English Edition) 2011年第3期85卷 581-597页

作者： wan Tianfeng zhu Hong School of Earth Sciences and Resources China University of Geosciences Beijing 100083 China

The Cambrian to Cretaceous paleomagnetic data from Chinese continental and adjacent blocks were collected using principles to obtain reliable and high-precision paleomagnetic data and to pay attention to the similarity of paleobiogeography and the coordination of tectonic *** Chinese continental blocks were laid up on the reconstruction of proposed global paleocontinents with almost the same ***,it can be clearly recognized that the global continents,including Chinese continental blocks,range along latitudes on the southern side of the equator during the Early Paleozoic. In the Paleozoic,Chinese continental blocks were still located among the Laurentia,Siberia and Gondwana plates,following the fast moving of the Siberia Plate northwards,the amalgamation in a north-south direction at the western parts of the Laurentia and Gondwana plates,and the Iapetus and Rheic Oceans were subducted,eventually to form a uniform Pangea in the Late *** Australian and Indian plates of Eastern Gondwana moved and dispersed gradually southwards, continued to extend the Paleo-Tethys *** Chinese continental and adjacent blocks were still located in the Paleo-Tethys Ocean,preserved the status of dispersion,gradually moving northwards, showing characteristics of ranging along a north-south orientation until the *** addition,a series of local collisions happened during the Triassic,and consequently most of the Chinese continental blocks were amalgamated into the Pangea,except for the Gangdise and Himalayan blocks. There was a counter-clockwise rotation of the Eastern Asian continent in the Jurassic and northwards migration of the Chinese continent in varying degrees during the Cretaceous,but the Himalayan and Indian plates did not collide into the Chinese continent during this period.

关键词： paleomagnetism paleogeographic reconstruction Paleozoic Mesozoic China

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An advanced higher-order theory for laminated composite plates with general lamination angles

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Acta Mechanica Sinica 2011年第5期27卷 720-729页

作者： Zhen Wu Hong zhu wan-Ji Chen Key Laboratory of Liaoning Province forComposite Structural Analysis of Aerocraft and Simulation Shenyang Aerospace University 110136 Shenyang China

This paper proposes a higher-order shear deformation theory to predict the bending response of the laminated composite and sandwich plates with general lamination *** proposed theory a priori satisfies the continuity conditions of transverse shear stresses at ***,the number of unknown variables is independent of the number of *** first derivatives of transverse displacements have been taken out from the inplane displacement fields,so that the C 0 shape functions are only required during its finite element *** to C 0 continuity requirements,the proposed model can be conveniently extended for implementation in commercial finite element *** verify the proposed theory,the fournode C 0 quadrilateral element is employed for the interpolation of all the displacement parameters defined at each nodal point on the composite *** results show that following the proposed theory,simple C 0 finite elements could accurately predict the interlaminar stresses of laminated composite and sandwich plates directly from a constitutive equation,which has caused difficulty for the other global higher order theories.

关键词： Laminated and sandwich composites Higherorder theory C 0 continuity requirement Transverse shear stress

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Electromigration in eutectic SnAg solder reaction couples with various ambient temperatures and current densities

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International Journal of Minerals,Metallurgy and Materials 2009年第6期16卷 685-690页

作者： Guang-chen Xu Fu Guo wan-rong zhu College of Materials Science and Engineering Beijing University of Technology Beijing 100124 China

The electromigration behavior of eutectic SnAg solder reaction couples was studied at various temperature （25 and 120℃ when the current density was held constant at 104 A/cm^2 or 5×10^3 A/cm^2. Under the current density of 104 A/cm^2, scallop type Cu6Sn5 spalls and migrates towards the direction of electron flow at room ambient temperature （25℃）, but transforms to layer type Cu3Sn and leaves Kirkendall voids in it at high ambient temperature （120℃）. Under the current density of 5×10^3 A/cm^2 plus room ambient temperature, no obvious directional migration of metal atoms/ions is found. Instead, the thermal stress induced by mismatch of dissimilar materials causes the formation of superficial valley at both interfaces. However, when the ambient temperature increases to 120℃, the mobility of metal atoms/ions is enhanced, and then the grains rotate due to the anisotropic property of β-Sn.

关键词： electromigration eutectic solder Joule heating intermetallic compound

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Modified Frequency Scaling Algorithm for FMCW SAR Data Processing

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Chinese Journal of Aeronautics 2007年第4期20卷 339-345页

作者： Jiang Zhihong Huang Fukan wan Jianwei Cheng zhu College of Electronic Science and Engineering National University of Defense Technology Changsha 410073 China

This paper presents a modified frequency scaling algorithm for frequency modulated continuous wave synthetic aperture radar （FMCW SAR） data processing. The relative motion between radar and target in FMCW SAR during reception and between transmission and reception will introduce serious dilation in the received signal. The dilation can cause serious distortions in the reconstructed images using conventional signal processing methods. The received signal is derived and the received signal in range-Doppler domain is given. The relation between the phase resulting from antenna motion and the azimuth frequency is analyzed. The modified frequency scaling algorithm is proposed to process the received signal with serious dilation. The algorithm can effectively eliminate the impact of the dilation. The algorithm performances are shown by the simulation results.

关键词： FMCW radar SAR radar imaging frequency scaling algorithm

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Cretaceous-Early Eocene Tectonic Stress Field in China

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Acta Geologica Sinica(English Edition) 1989年第3期63卷 227-239页

作者： wan Tianfeng and zhu Hong China University of Geosciences, Beijing, China 2wan Tianfeng male born in 1938 engaged in geological education since 1959 and now is a professor of the Teaching and Research Group of Structural Geology China University of Geosciences Beijing 100083. China University of Geosciences Beijing China

The Cretaceous-early Eocene tectonic stress field in China was reconstructed using the data of 369 largeand medium-scale flexural folds and 157 joint sets. It was found that the maximum compressive principal stress axis in eastern China dips 32° NE (nearly horizontal), and strikes SW 212°, whereas that in western China dips 15° NE (also nearly horizontal) and trends SW 195°. The estimation of the dip angles of fold limbs and the palaeotectonic stress values indicates that there was a tendency of gradual weakening of tectonism from southwestern to northeastern China in the Cretaceous-early Eocene. At the depth of 2-3 km, the differential stress value changes from 183 MPa in Tibet to 100 MPa in North and East China.The authors consider that the tectonic stress of this period was related to the north-northeastward movement and push of the Indian-Australian plate.

关键词： Cretaceous-Early Eocene Tectonic Stress Field in China

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Comparison of Seven Kinetic Equations for K Release and Application of Kinetic Parameters

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Pedosphere 2007年第1期17卷 124-129页

作者： Lü Xiao-Nan XU Jian-Ming MA wan-zhu LU Yun-Fu Institute of Soils and Fertilizers Zhejiang Academy of Agricultural Sciences Hangzhou 310021 （China） College of Environmental Sciences and Resources Zhejiang University Hangzhou 310029 （China）

Corn field experiments with two treatments, NP and NPK, where N in the form of urea, P in the form of calcium phosphate, and K in the form of KCl were applied at rates of 187.5, 33.3, and 125 kg ha^-1, respectively, on soils derived from Quaternary red clay were conducted in the hilly red soil region of Zhejiang Province, China. Plant grains and stalks were collected for determination of K content. Seven equations were used to describe the kinetics of K release from surface soil samples taken before the corn experiments under electric field strengths of 44.4 and 88.8 V cm^-1 by means of electro-ultrafiltration （EUF） and to determine if their parameters had a practical application. The second-order and Elovich equations excellently described K release; the first-order, power function, and parabolic diffusion equations also described K release well; but the zero-order and exponential equations were not so good at reflecting K release. Five reference standards from the field experiments, including relative grain yield （yield of the NP treatment/yield of the NPK treatment）, relative dry matter yield （dry matter of the NP treatment/dry matter of the NPK treatment）, quantity of K uptake in the NP treatment （no K application）, soil exchangeable K, and soil HNO3-soluble K, were used to test the effectiveness of equation parameters obtained from the slope or intercept of these equations. Correlations of the ymax （the maximum desorbable quantity of K） in the second-order equation and the constant b in the first-order and Elovich equations to all five reference standards were highly significant （P ≤ 0.01）. The constant a in the power function equation was highly significant （P 〈 0.01） for four of the five reference standards with the fifth being significant （P ≤ 0.05）. The constant b in the parabolic equation was also significantly correlated （P ≤ 0.05） to the relative grain yield and soil HNO3-soluble K. These suggested that all of these parameters could be used to estimate t

关键词： corn K release kinetic equation kinetic parameters

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Metal/nanocarbon layer current collectors enhanced energy efficiency in lithium-sulfur batteries

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Science Bulletin 2017年第18期62卷 1267-1274页

作者： Jia-Qi Huang Pei-Yan Zhai Hong-Jie Peng wan-Cheng zhu Qiang Zhang Beijing Key Laboratory of Green Chemical Reaction Engineering and Technology Department of Chemical Engineering Tsinghua University Advanced Research Institute of Multidisciplinary Science Beijing Institute of Technology Department of Chemical Engineering Qufu Normal University

Lithium-sulfur （Li-S） batteries with intrinsic merits in high theoretical energy density are the most promising candidate as the next-generation power sources. The strategy to achieve a high utilization of active materials with high energy efficiency is strongly requested for practical applications with less energy loss during repeated cycling. In this contribution, a metal/nanocarbon layer current collector is proposed to enhance the redox reactions of polysulfides in a working Li-S cell. Such a concept is demon- strated by coating graphene-carbon nanotube hybrids （GNHs） on routine aluminum （AI） foil current collectors. The interracial conductivity and adhesion between the current collector and active material are significantly enhanced. Such novel cell configuration with metal/nanocarbon layer current collectors affords abundant Li ions for rapid redox reactions with small overpotential. Consequently, the Li-S cells with nanostructured current collectors exhibit an initial discharge capacity of 1,113 mAh g-1 at 0.5 C, which is -300 mAh g-1 higher than those without a GNH coating layer. The capacity retention is 73% for cells with GNH after 300 cycles. A reduced voltage hysteresis and a high energy efficiency of ca. 90% are therefore achieved. Moreover, the AI/GNH layer current collectors are easily implanted into current cell assembly process for energy storage devices based on complex multi-electron redox reactions （e.g., Li-S batteries, Li-O2 batteries, fuel cells, and flow batteries）.

关键词： Lithium-sulfur battery Nanostructured current collectors Polysulfides Energy efficiency Pouch cell

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Research on extraction and reproduction of deformation camouflage spot based on generative adversarial network model

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Defence Technology（防务技术） 2020年第3期16卷 555-563页

作者： Xin Yang Wei-dong Xu Qi Jia Ling Li wan-nian zhu Ji-yao Tian Hao Xu National Key Laboratory of Lightning Protection and Electromagnetic Camouflage Amy Engineering UniversityNanjingJiangsu210007China Teaching and Research Office of Camouflage in Training Center Army Engineering UniversityXuzhouJiangsu221004China

The method of describing deformation camouflage spots based on feature space has some shortcomings,such as inaccurate description and difficult *** on the strong fitting ability of the generative adversarial network model,the distribution of deformation camouflage spot pattern can be directly fitted,thus simplifying the process of spot extraction and *** requirements of background spot extraction are analyzed *** calculation formula of limiting the range of image spot pixels is given and two kinds of spot data sets,forestland and snowfield,are *** feature is decomposed into shape,size and color features,and a GAN(Generative Adversarial Network)framework is *** effects of different loss functions on network training results are analyzed in the *** the meantime,when the input dimension of generator network is 128,the balance between sample diversity and quality can be *** effects of sample generation are investigated in two ***,the probability of the generated spots being distinguished in the background is counted,and the results are all less than 20% and mostly close to ***,the features of the spot shape are calculated and the independent sample T-test is applied to verify that the features are from the same distribution,and all the P-Values are much higher than *** subjective and objective methods prove that the spots generated by this method are similar to the background *** proposed method can directly generate the desired camouflage pattern spots,which provides a new technical method for the deformation camouflage pattern design and camouflage effect evaluation.

关键词： Deformation camouflage Generative adversarial network Spot feature Shape description

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Magneto-optical Kerr and Faraday effects in bilayer antiferromagnetic insulators

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Chinese Physics B 2023年第8期32卷 472-478页

作者：朱婉情单文语 Department of Physics School of Physics and Materials ScienceGuangzhou UniversityGuangzhou 510006China

Control and detection of antiferromagnetic topological materials are challenging since the total magnetization *** we investigate the magneto-optical Kerr and Faraday effects in bilayer antiferromagnetic insulator Mn *** find that by breaking the combined mirror symmetries with either perpendicular electric field or external magnetic moment,Kerr and Faraday effects *** perpendicular electric field,antiferromagnetic topological insulators(AFMTI)show sharp peaks at the interband transition threshold,whereas trivial insulators show small adjacent positive and negative *** voltage and Fermi energy can be tuned to reveal the differences between AFMTI and trivial *** find that AFMTI with large antiferromagnetic order can be proposed as a pure magneto-optical rotator due to sizable Kerr(Faraday)angles and vanishing *** external magnetic moment,AFMTI and trivial insulators are significantly different in the magnitude of Kerr and Faraday angles and *** the qualitative behaviors,AFMTI shows distinct features of Kerr and Faraday angles when the spin configurations of the system *** phenomena provide new possibilities to optically detect and manipulate the layered topological antiferromagnets.

关键词： magneto-optical Kerr and Faraday effects antiferromagnetic topological insulators bilayer systems

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Endoscopic nasal surgery for mucocele and pyogenic mucocele of turbinate: Three case reports

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World Journal of Clinical Cases 2022年第32期10卷 12007-12014页

作者： Shu-Juan Sun Ai-Ping Chen Yu-zhu wan Hong-Zhi Ji Department of Otolaryngology-Head and Neck Surgery Shandong Provincial ENT HospitalShandong UniversityJinan 250022Shandong ProvinceChina

BACKGROUND Cases of turbinate mucocele or pyogenic mucocele are extremely *** nasal endoscopy,turbinate hypertrophy can be detected in patients with turbinate or pyogenic ***,in many instances,differentiating between turbinate hypertrophy and turbinate mucocele is *** examinations,such as computed tomography(CT)or magnetic resonance imaging(MRI),are essential for the accurate diagnosis of turbinate ***,we report three cases of mucocele or pyogenic mucocele of turbinate,including their clinical presentation,imaging findings,and treatments,to help rhinologists understand this condition *** SUMMARY Three cases of turbinate and pyogenic mucocele were encountered in our *** all patients,nasal obstruction and headache were the most common symptoms,and physical examination revealed hypertrophic *** CT scan,mucocele appeared as non-enhancing,homogeneous,hypodense,well-defined,rounded,and expansile ***,MRI clearly illustrated the cystic nature of the lesion on T2 *** patients with inferior turbinate mucocele underwent mucocele lining removal,while the patient with pyogenic mucocele underwent endoscopic middle turbinate *** patients were followed up on the first,third,sixth month,and 1 year after discharge,and no complaints of headache and nasal congestion were reported during this *** In conclusion,both CT and MRI are helpful in the diagnosis of turbinate or pyogenic ***,endoscopic nasal surgery is considered to be the most effective treatment method.

关键词： Mucocele Pyogenic mucocele Inferior turbinate Middle turbinate Concha bullosa Case report

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