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Discovery of the choristodere Hyphalosaurus baitaigouensis from the Lower Cretaceous Jiufotang Formation of western Liaoning,China and its paleobiogeographic significance

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Journal of Palaeogeography 2024年第3期13卷 547-562页

作者： Li-jun zhang Shu-An Ji Hai-Chun zhang South China Sea Culture Museum Hainan Tropical Ocean UniversitySanya 572022Hainan ProvinceChina Key Laboratory of Stratigraphy and Paleontology Ministry of Natural ResourcesInstitute of GeologyChinese Academy of Geological SciencesBeijing 100037China State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology and Center for Excellence in Life and PaleoenvironmentChinese Academy of SciencesNanjing 210008Jiangsu ProvinceChina

The water-living reptile genus Hyphalosaurus was previously discovered in the Lower Cretaceous Yixian Formation bearing the middle Jehol Biota in western Liaoning,*** complete skeletons of Hyphalosaurus are reported for the first time from the Jiufotang Formation bearing the late Jehol Biota at two sites in western *** show the typical characteristics of Hyphalosaurus baitaigouensis in terms of the contact between some cranial bones and the number of cervical and dorsal vertebrae,and therefore are assigned to *** discovery extends the stratigraphic range of this species from the Yixian Formation to the overlying Jiufotang *** paper further briefly compares the main characteristics of the two skeletons,summarizes the temporal and spatial distribution of Hyphalosaurus,and discusses the palaeogeographic evolution of western Liaoning at the middle and late Jehol Biota stages based on the aquatic habits of Hyphalosaurus and the geological background of western *** analytical results show that the volcanic downwarped lakes,with distinct geographical divisions in western Liaoning during the deposition of the Yixian Formation,had not completely disappeared till the deposition of the Jiufotang *** palaeo-lake in the Fuxin-Yixian Basin underwent the process of generation,expansion and shrinkage during the depositional period of the Yixian Formation and finally merged into a large *** palaeo-Dalinghe River,which connected the main basins in western Liaoning during the depositional period of the Jiufotang Formation,was formed simultaneously.

关键词： Western liaoning Jehol biota Jiufotang formation Hyphalosaurus baitaigouensis Palaeobiogeography

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Two types of dynamic cool coronal structures observed with STEREO and Hinode

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Research in Astronomy and Astrophysics 2009年第12期9卷 1368-1376页

作者： jun zhang Le-Ping Li Key Laboratory of Solar Activity National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China

Solar coronal loops show significant plasma motions during their formation and eruption stages. Dynamic cool coronal structures, on the other hand, are often observed to propagate along coronal loops. We report on the discovery of two types of dynamic cool coronal structures, and characterize their fundamental properties. Using the EUV 304 A images from the Extreme UltraViolet Imager （EUVI） telescope on the Solar TErrestrial RElation Observatory （STEREO） and the Ca Ⅱ filtergrams from the Solar Optical Telescope （SOT） instrument on Hinode, we study the evolution of an EUV arch and the kinematics of cool coronal structures. The EUV 304A observations show that a missile-like plasmoid moves along an arch-shaped trajectory, with an average velocity of 31 km s^- 1. About three hours later, a plasma arch forms along the trajectory, subsequently the top part of the arch fades away and disappears; meanwhile the plasma belonging to the two legs of the arch flows downward to the arch＇s feet. During the arch formation and disappearance, SOT Ca Ⅱ images explore dynamic cool coronal structures beneath the arch. By tracking these structures, we classify them into two types. Type I is thread- like in shape and flows downward with a greater average velocity of 72 km s-l; finally it combines with a loop fibril at a chromospheric altitude. Type Ⅱ is shape-transformable and sometimes rolling as it flows downward with a smaller velocity of 37 km s-1, then disappears insularly in the chromosphere. It is suggested that the two types of structures are possibly controlled by different magnetic configurations.

关键词： Sun: chromosphere -- Sun: UV radiation -- Sun: activity

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Two-Flux Colliding Plane Waves in String Theory

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Communications in Theoretical Physics 2005年第3X期44卷 463-472页

作者： CHEN Bin zhang jun-Feng Department of Physics Peking University Beijing 100871 China Department of Mathematics Capital Normal University Beijing 100037 China

We construct the two-flux colliding plane wave solutions in higher-dimensional gravity theory with dilaton,and two complementary fluxes. Two kinds of solutions have been obtained: Bell-Szekeres (BS) type and homogeneous type. After imposing the junction condition, we find that only the BS type solution is physically well-defined. Furthermore, we show that the future curvature singularity is always developed for our solutions.

关键词： colliding plane wave string theory

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Cold Model Study on Mg Desulfurization of Hot Metal Under Mechanical Stirring

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Journal of Iron and Steel Research International 2013年第12期20卷 1-6页

作者： LIU Yan zhang Zi-mu LIU Jian-nan zhang jun-hua Masamichi Sano zhang jun Key Laboratory of Ecological Utilization of Multi-metal Intergrown Ores of Ministry of Education School of Materials and MetallurgyNortheastern University Beijing Institute of Technology Dalian University of Technology Nagoya University

The new method of in-situ desulfurization with mechanical stirring of new type impellers was introduced, in which the bubble＇s dispersion and disintegration of magnesium vapor were the key to boosting the desulfurization efficiency and increasing the utilization rate of magnesium. Effects of different new type of impellers on bubble dis persion and disintegration were studied through bubble image analysis, gas-liquid mass transfer, and power con- sumption levels of different impeller structures. The results showed that the sloped swept-back blade impeller-2 pro- duces optimal bubble＇s dispersion and disintegration, as well as higher volumetric mass transfer coefficient and CO2 gas utilization while consuming the least power. Numerical simulation result with Fluent software also showed that the sloped swept-back blade impeller-2 has higher turbulent kinetic energy and better velocity distribution than the other two impellers.

关键词： gas injection refining eccentric mechanical stirring bubble disintegration bubble dispersion volumetric mass transfer coefficient Mg desulfurization hot metal

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Spin-orbit coupling in Bose-Einstein condensate and degenerate Fermi gases

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Frontiers of physics 2014年第5期9卷 598-612页

作者： Peng-jun Wang Jing zhang State Key Laboratory of Quantum Optics and Quantum Optics Devices Institute of Opto-Electronics Shanxi University Taiyuan 030006 China

We review our recent experimental realization and investigation of a spin orbit （SO） coupled Bose Einstein condensate （BEC） and quantum degenerate Fermi gas. By using two counter-propagathlg Ranlan lasers and controlling the different frequency of two R,aman lasers to engineer the atom light interaction, we first study the SO coupling in BEC. Then we study SO coupling in Fermi gas. We, observe the spin dephasing in spin dynamics and momentum distribution asymmetry of the equilibrium state as halhnarks of SO coupling in a Fermi gas. To clearly reveal the, property of SO coupling Fermi gas, we also study the momentmn-resolved radio-frequency spectroscopy which characterizes the energy momentum dispersion and spin composition of the quantum states. We observe the change of errmion surfaces in different helieity branches with different atomic density, which indicates that a Lifshitz transition of the Fermi surface topology change can be found by further cooling the system. At last, we study the momentum-resolved Raman spectroscopy of an ultracoht Fermi gas.

关键词： spin-orbit coupling Bose Einstein condensate Fermi gases topological change momentum-resolved radio-frequency spectroscopy momentum-resolved Raman spectroscopy

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Effects of Surface Flux Parameterization on the Numerically Simulated Intensity and Structure of Typhoon Morakot(2009)

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Advances in Atmospheric Sciences 2016年第1期33卷 58-72页

作者： Jie MING jun A.zhang Key Laboratory of Mesoscale Severe Weather/MOE and School of Atmospheric Sciences Nanjing UniversityNanjing 210023 Hurricane Research Division Atlantic Oceanographic and Meteorological LaboratoryNational Oceanographic and Atmospheric AdministrationMiamiFLUSA Rosenstiel School of Marine and Atmospheric Science University of Miami MiamiFLUSA

The effects of surface flux parameterizations on tropical cyclone（TC） intensity and structure are investigated using the Advanced Research Weather Research and Forecasting（WRF-ARW） modeling system with high-resolution simulations of Typhoon Morakot（2009）.Numerical experiments are designed to simulate Typhoon Morakot（2009） with different formulations of surface exchange coefficients for enthalpy（C_K） and momentum（C_D） transfers,including those from recent observational studies based on in situ aircraft data collected in Atlantic *** results show that the simulated intensity and structure are sensitive to C_K and C_D,but the simulated track is *** with previous studies,the simulated storm intensity is found to be more sensitive to the ratio of C_K/C_D than to C_K or C_D *** pressure-wind relationship is also found to be influenced by the exchange coefficients,consistent with recent numerical *** paper emphasizes the importance of C_D and C_K on TC structure *** results suggest that C_D and C_K have a large impact on surface wind and flux distributions,boundary layer heights,the warm core,and *** to available observations,the experiment with observed C_D and C_K generally simulated better intensity and structure than the other experiments,especially over the *** reasons for the structural differences among the experiments with different C_D and C_K setups are discussed in the context of TC dynamics and thermodynamics.

关键词： Typhoon Morakot surface flux parameterization exchange coefficients boundary layer

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Integral Self-affine Tiles of Bandt's Model

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Acta Mathematicae Applicatae Sinica 2010年第1期26卷 169-176页

作者： Hui Rao Li-jun zhang Department of Mathematics and Statistics Central China Normal University Wuhan 430079 China Department of Mathematics Tsinghua University Beijing 100084 China

Integral self-affine tiling of Bandt＇s model is a generalization of the integral self-affine tiling. Using ergodic theory, we show that the Lebesgue measure of the tile is a rational number where the denominator equa... 详细信息

关键词： IFS self-affine tiling invariant measure _

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Ruthenium(Ⅲ) chloride as an efficient catalyst for the synthesis of perimidine derivatives under mild conditions

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Chinese Chemical Letters 2007年第9期18卷 1057-1060页

作者： Jing zhang Song Lin zhang jun Min zhang Key Laboratory of Organic Synthesis of Jiangsu Province College of Chemistry and Chemical EngineeringDushu Lake CampusSuzhou UniversitySuzhou 215123China College of Chemistry and Environmental Science Henan Normal UniversityXinxiang 453007China

Various biologically important perimidine derivatives have been synthesized efficiently from various ketones and naphthalene- 1,8-diamine by using a catalytic amount of RuCl_3(1 mol%).This method is a very simple and ... 详细信息

关键词： Ruthenium(Ⅲ)chloride Pedmidine derivatives Naphthalene-1,8-diamine Synthesis Catalyst

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Conserved Gross-Pitaevskii equations with a parabolic potential

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Communications in Theoretical Physics 2022年第10期74卷 30-36页

作者： Shi-min Liu Da-jun zhang Department of Mathematics Shanghai UniversityShanghai 200444People’s Republic of China

An integrable Gross–Pitaevskii equation with a parabolic potential is presented where particle density|u|^(2)is *** also present an integrable vector Gross–Pitaevskii system with a parabolic potential,where the total particle density∑^(n)_(j)=_(1)∣u_(j)∣^(2)is *** equations are related to nonisospectral scalar and vector nonlinear Schrödinger *** many conservation laws are *** transformations between the standard isospectral nonlinear Schrödinger equations and the conserved Gross–Pitaevskii equations,both scalar and vector cases are *** and dynamics are analyzed and *** solutions exhibit features of localized-like waves.

关键词： Gross-Pitaevskii equation gauge transformation nonisospectral conserved particle density

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A Novel Process for High-efficient Synthesis of One-dimensional Carbon Nanomaterials from Flames

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Journal of Materials Science & Technology 2008年第4期24卷 603-607页

作者： XianG QI jun zhang Chunxu PAN Department of Physics and Key Laboratory of Acoustic and Photonic Materials and Devices of Ministry of Education Wuhan University Wuhan 430072 China Center for Electron Microscopy Wuhan University Wuhan 430072 China

The substrate pre-treatment plays a key role in obtaining hollow-cored carbon nanotubes （CNTs） and solid-cored carbon nanofibers （CNFs） from flames. This paper introduces a simply and high-efficient process by coating a NiSO4 or FeSO4 layer on the substrate as catalyst precursors. Comparing with the regular pre-treatment methods, the present experiments showed that the coating pre-treatment provided the following advantages： 1） greatly shortening the synthesis time; 2） available variant substrates and carbon sources; 3） narrowing the diameters distribution. The sulfate is considered to be a crucial factor at the growth of CNTs and CNFs, because it increases the surface energy of catalyst particles and the surface specificity of sulfurs action in metallic grains. This novel process provides a possibility for high quality and mass production of CNTs and CNFs from flames.

关键词： Carbon nanotubes Carbon nanofibers Flames Sulfate

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