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一种超声速射流计算方法与实验验证

推进技术 2020年第2期41卷 314-323页

作者：丛彬彬万田樊菁中国科学院力学研究所北京100190 中国科学院大学工程科学学院北京100049

高温射流流场计算是尾焰辐射目标特性计算的前提,然而由于缺少可靠实验数据,针对湍流超声速射流的数值模拟多集中于低温射流,高温射流计算与实验的对比工作还很少见。利用k-ωSST双方程湍流模型,模拟了多个典型超声速射流实验的流场速... 详细信息

高温射流流场计算是尾焰辐射目标特性计算的前提,然而由于缺少可靠实验数据,针对湍流超声速射流的数值模拟多集中于低温射流,高温射流计算与实验的对比工作还很少见。利用k-ωSST双方程湍流模型,模拟了多个典型超声速射流实验的流场速度与温度分布,通过与实验结果进行对比,建立了一种超声速射流计算方法。首先,通过对比多个低温射流的实验与计算结果,探索了湍流模型中可压缩修正以及来流湍动粘性比对超声速射流计算结果的影响;进而,针对火箭发动机尾焰实验,计算尾焰流场与流场红外辐射,流场辐射计算结果与实验观测结果符合较好,进一步验证了计算方法。最终认为经过可压缩修正的k-ωSST双方程湍流模型结合湍动粘性比取值30可以作为超声射流计算中较为典型的湍流计算方法。

关键词：尾焰超声速射流红外辐射湍动粘性比可压缩修正

Some notes on the spectral perturbations of the signless Laplacian of a graph

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Applied Mathematics(A Journal of Chinese Universities) 2014年第2期29卷 241-248页

作者： YU Gui-dong CAI Gai-xiang fan Yi-zheng School of Mathematics & Computation Sciences Anqing Normal University School of Mathematical Sciences Anhui University

Let G be a simple graph and let Q（G） be the signless Laplacian matrix of G. In this paper we obtain some results on the spectral perturbation of the matrix Q（G） under an edge addition or an edge contraction.

关键词： Graph signless Laplacian matrix spectral perturbation.

Synthesis of polynorbornene with pendant moiety bearing azide and terminal alkyne groups

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Chinese Chemical Letters 2011年第7期22卷 785-788页

作者： Ze Zhang Zhi Wei Peng Kun Zeng fan School of Biochemical Engineering Anhui Polytechnic University Wuhu 241000 China Department of Chemistry University of Science and Technology of China Hefei 230026 China

A powerful approach to the synthesis of an unprecedented polynorbornene with pendant moiety bearing azide and terminal alkyne groups is developed. Two key intermediates, namely, 3-azido-5-（2-（trimethylsilyl）ethynyl） benzyl alcohol and 4-（4-azatricyclo [5.***.1.0^2.6]dec-8-en-4-yl） benzoic acid, were optimally synthesized for convergent synthesis of the corresponding monomer.

关键词： Polynorbomene Azide Alkyne Esterification Metathesis

The　Enhancement　of　Fluorescence　of　The　Squaraine　Dye　LB　Films　by　Overcoating　of　Glycolipids

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Chinese Chemical Letters 1996年第10期7卷 935-938页

作者： Li, JR fan, CY Li, BF Jiang, L ACAD SINICA INST PHOTOG CHEMBEIJING 100101PEOPLES R CHINA

The influence of overcoating layers of dialkylglycerylether-β-glucosides(A)1,2O-dialkylglycerylethers(B) and arachidic acid (C20) on the fluorescence of the squaraine dye(SQ) and C20 mixed film were investigated by fluorescence and time-resolved fluorescence measurements. An apparent increase in fluorescence intensity for three layer mixed film of SQ and C20 were obtained by overcoating A in comparison with the small change fluorescence intensity for SQ dye mixed film by overcoating B or C20.

关键词： LB Dye Films Enhancement Fluorescence

The Middle Miocene lobe-shaped and band-shaped submarine fans in the Lingshui Sag,Qiongdongnan Basin:source-to-sink system,genesis and implication

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Acta Oceanologica Sinica 2024年第4期43卷 61-79页

作者： Xingzong yao Congjun Feng Hongjun Qu Min Zhang Daming Li State Key Laboratory of Continental Dynamics Northwest UniversityXi’an 710069China Department of Geology Northwest UniversityXi’an 710069China Exploration and Development Technology Research Center of Yanchang Oilfield Co. Ltd.Yan’an 716000China Chexplor Resource Exploration Technology Co. Ltd.Huaibei 235000China

Deepwater oil and gas exploration is the key to sustainable breakthroughs in petroleum exploration *** Central Canyon gas field has confirmed the Lingshui Sag is a hydrocarbon-generating sag,and the deepwater reservoirs in the Lingshui Sag still have more fabulous oil and gas exploration *** on drilling data and three-dimensional(3D)seismic data,this paper uses seismic facies analysis,seismic attribute analysis,and coherence slice analysis to identify the types of submarine fans(lobe-shaped and band-shaped submarine fans)that developed in the Lingshui Sag during the Middle Miocene,clarify the source-to-sink system of the submarine fans and discuss the genesis mechanism of the submarine *** results show that:(1)the deepwater source-to-sink system of the Lingshui Sag in the Middle Miocene mainly consisted of a“delta(sediment supply)-submarine canyon(sediment transport channel)-submarine fan(deepwater sediment sink)”association;(2)the main factor controlling the formation of the submarine fans developed in the Lingshui Sag was on the relative sea level decline;and(3)the bottom current reworked the lobe-shaped submarine fan that developed in the northern Lingshui Sag and formed the band-shaped submarine fan with a greater sand *** paper aims to provide practical geological knowledge for subsequent petroleum exploration and development in the deepwater area of the Qiongdongnan Basin through a detailed analysis of the Middle Miocene submarine fan sedimentary system developed in the Lingshui Sag.

关键词： submarine fan source-to-sink system genesis mechanism Middle Miocene Lingshui Sag

Theory of gas extraction from coal seams and its use

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Journal of Coal Science & Engineering(China) 2012年第3期18卷 276-279页

作者： fan Xi-sheng Mine Safety Technology Branch China Coal Research InstituteBeijing 100013China State Key Laboratory of Coal Mining and Clean Utilization(China Coal Research Institute) Beijing 100013China

Gas extraction is one of the main measures of control and use of gas of coal mines. At present, the design method is under the experimental period and do not satisfy the need of practice. In this paper, the theory of gas extraction of coal seams based upon Darcy law was studied. Mathematical model of gas extraction of coal seams was established and two kinds of solv- ing approaches based on computer software and linear approximation were given. The rightness and the validities of the model were examined with a practical example. Results obtained can be used to determine and optimize the parameters related etc.

关键词： coal seam gas gas extraction linear approximation

Synthesis and Optical Properties of Ce-doped ZnO

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Chemical Research in Chinese Universities 2008年第3期24卷 266-269页

作者： YANG jing-hai GAO Ming ZHANG Yong-jun YANG Li-li LANG Ji-hui WANG Dan-dan WANG Ya-xin LIU Hui-lian fan Hou-gang WEI Mao-bin LIU Fu-zhu The Institute of Condensed State Physics Jilin Normal University Siping 136000 P R. China Key Laboratory of Excited State Processes Changehun Institute of Optics Fine Mechanics and Physics Chinese Academy of Sciences Changehun 130033 P R. China School of Material Science and Engineering Jiangsu University Zhenjiang 210013 P. R. China

ZnO nanorods were synthesized using the sol-gel method, and the effects of annealing temperature and Ce doping on the morphologies and optical properties of ZnO nanostructures were investigated in detail. The XRD measurements showed that the as-synthesized ZnO nanostructures had a hexagonal wurtzite structure. SEM images showed that uniform nanorods formed at 900 °C. Photoluminescence measurements showed an ultraviolet emission peak and a relatively broad visible light emission peak for the samples sintered at different temperatures. The UV emission peak bathochromically shifted when the annealing temperature rose from 850 to 1000 °C. Ce doping decreased the synthesized temperature of the ZnO nanorods to 500 °C, and the UV peaks hypsochromically shifted.

关键词： Annealing temperature Ce-doped ZnO Optical property

The influence of Si substitution on soft magnetic properties and crystallization behavior in Fe_(83)B_(10)C_(6-x)Si_xCu_1 alloy system

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Science China(Technological Sciences) 2012年第9期55卷 2416-2419页

作者： fan XingDu MEN He MA AiBin SHEN BaoLong College of Mechanics and Materials Hohai UniversityNanjing 210098China Zhejiang Province Key Laboratory of Magnetic Materials and Application Technology Key Laboratory of Magnetic Materials and DevicesNingbo Institute of Material Technology&EngineeringChinese Academy of SciencesNingbo 315201China

In this study, the soft magnetic properties and crystallization behavior of Fes3B10C6-xSixCul （x=0-4） nanocrystalline alloys prepared by annealing the melt-spun amorphous ribbons have been investigated. It is found that in the Fe83B10C6-xSixCU1 alloy system, the coercivity （Hc） decreases slightly with increasing Si addition and exhibits a minimum value with composition of x = 2, while the effective permeability （Ue） shows an opposite variation trend. The saturation magnetic flux density （Bs） shows a slightly decreasing trend owing to the decreasing volume fraction of nanocrystalline phase. The Fe83B10CaSi2Cu1 nanocrystalline alloy exhibits excellent soft magnetic properties with a high Bs of 1.78 T, high ue of 13 600 and low Hc of 4 A/m.

关键词： soft magnetic alloy Fe-based nanocrystalline alloy high saturation magnetic flux density low coercivity

Uniform Exponential Attractors for Second Order Non-autonomous Lattice Dynamical Systems

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Acta Mathematicae Applicatae Sinica 2017年第3期33卷 587-606页

作者： Xiao-peng ZHOU Fu-qi YIN Sheng-fan ZHOU School of Mathematics and Computational Science Xiangtan University Department of Mathematics Zhejiang Normal University

In this paper, the existence of a uniform exponential attractor for a second order non-autonomous lattice dynamical system with quasiperiodic symbols acting on a closed bounded set is considered. Firstly, the existence and uniqueness of solutions for the considered systems which generate a family of continuous processes is shown, and the existence of a uniform bounded absorbing sets for the processes is proved. Secondly, a semigroup defined on a extended space is introduced, and the Lipschitz continuity, a-contraction and squeezing property of this semigroup are proved. Finally, the existence of a uniform exponential attractor for the family of processes associated with the studied lattice dynamical systems is obtained.

关键词： uniform exponential attractor quasiperiodic symbols a family of processes squeezing property lattice dynamical systems