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Fractal　and　chaotic　phenomena　of　seismic　dissipated　energy　in　an　energy　system　of　engineering　struct

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Acta Seismologica Sinica(English Edition) 1998年第4期11卷 479-486页

作者： Cui, Yu-Hong Nie, Yong-An Yan, Zong-Da Wu, Guo-You Department of Mechanics Tianjin University Tianjin China Seismological Bureau of Tianjin Tianjin China

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关键词： phenomena 崔玉 Fractal

Investigating dynamic mechanisms of geological phenomena using methodology of computational geosciences:An example of equal-distant mineralization in a fault

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Science China Earth Sciences 2008年第7期51卷 947-954页

作者： B.E.HOBBS A.ORD CSIRO Division of Exploration and Mining P. O. Box 1130 Bentley WA 6102 Australia

This paper presents a research methodology associated with approximately a decade old computa- tional geosciences. To demonstrate how it can be used to investigate the dynamic mechanisms of geological phenomenon, we use as an example the equal-distant distribution of gold deposits in a three-dimensional permeable fault within the Yilgarn Craton, Western Australia. The related numerical results demonstrate that: (1) convective pore-fluid flow in fluid-saturated porous media is the control- ling dynamic mechanism leading to the equal-distant distribution of gold deposits along the fault; (2) the main characteristic of the new methodology is to change the traditionally used empirical, descrip- tive and qualitative methodology into the fundamentally scientific principles based predictive and quantitative methodology. Thus, this new methodology provides a modern scientific research tool for investigating the dynamic mechanisms associated with observed geological phenomena in nature.

关键词： computational geosciences research methodology geological phenomena dynamic mechanisms

EXPERIMENTAL INVESTIGATION ON ORDERED AND CHAOTIC phenomena OF VORTEX SHEDDING IN THE WAKE FLOW BEHIND A TWO-DIMENSIONAL CIRCULAR CYLINDER

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Science China Mathematics 1992年第1期35卷 81-90页

作者：魏中磊吴忠 H.E.FIEDLER Department of Mechnics Peking University Beijing 100871 PRC Hermann-Fottinger Institut Technische Universitat Berlin 1000 Berlin 12

In this paper, some preliminary experiments of ordered and chaotic vortex sheddingsbehind a 2--D circular cylinder at Reynolds numbers ranging from R_e=50 to 400 are presented.A transition in vortex shedding from the laminar to chaotic state occurs at Re=184.6-193.5,but it is seemingly not through the quasi--periodicity routes. There is a couple of dis-continuities in slope on the curve of the relationship between the vortex shedding frequencyand Reynolds number. The discontinuity at Re = 70 might correspond to the change of themode of the oblique vortex shedding. The second one at Re = 193.5 is responsible for thetransition from the ordered to the chaotic state.

关键词： ordered and chaotic phenomena vortex shedding wake.

Special magnetic phenomena in heavily doped La_(0.7-x)Dy_xSr_(0.3)MnO_3 system

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Science China(Physics,Mechanics & Astronomy) 2008年第1期51卷 90-97页

作者： LIU Ning 1,2 ,YAN GuoQing 1,3 ,CAI ZhiRang 1 ,PI Li 2 ,ZHANG Bei 2 &TONG Wei 2 1 Department of Physics,Suzhou College,Suzhou 234000,China 2 Structure Research Laboratory,University of Science and Technology of China,Hefei 230026,China 3 National Laboratory of Solid State Microstructures,Physics Department,Nanjing University,Nanjing 210093,China Department of Physics Suzhou College Suzhou China Structure Research Laboratory University of Science and Technology of China Hefei China National Laboratory of Solid State Microstructures Physics Department Nanjing University Nanjing China

The magnetism in heavily Dy doped La0.7-xDyxSr0.3MnO3(0.40≤x≤0.70)system is studied in this *** M-T relation seems to be complicated with the increase of *** sample with x=0.40,AFM behavior exists at T≤TN and M-T curves under zero field cooling(ZFC)and field cooling(FC)exhibit typical behavior of spincluster glass state above *** the sample with x=0.50,the M-T curve under ZFC exhibits a valley at a low temperature while the M-T curve under FC exhibits the negative magnetization below *** samples with x=0.60,0.70,their ZFC M-T curves are similar to that of x=0.50,but the FC M-T curves do not exhibit negative values any *** the peculiar phenomena above are well explained by Néel double-lattice model combined with M-H relation at typical *** molecular field theory fits well the negative magnetization for x=0.50.

关键词： heavily doped special magnetic phenomena double-lattice model

Numerical simulation of flow phenomena and optimum operation of tundish

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Journal of Central South University of Technology 2003年第2期10卷 155-158页

作者：时章明鄂加强刘春洋梅炽张全周应其 School of Energy and Power Engineering Central South University Xiangtan Iron and Steel Group Corporation

To enhance the quality of grade 20 carbon-steel on the continuous casting production line, the mechanism of forming blowholes and non-metallic inclusions in billets and numerical simulation of flow phenomena about liquid steel in tundish were studied. The results show that the configuration and operation of tundish play an important part in quality assurance of grade 20 carbon-steel products. By optimizing the configuration of the tundish, the depth of liquid bath in tundish is enhanced, the impact of liquid steel is decreased, and the residence time of liquid steel is lengthened, which is useful for eliminating inclusions and blowholes and improving the service life of tundish. Improving the pouring and tapping operation of liquid steel can avoid the contact of liquid steel with air, and decrease re-oxidation. Strict control of the superheat degree of casting liquid steel can decrease the non-metallic inclusion content of the re-oxidation in billets and reduce the erosion of tundish. The inclusions and blowholes in the continuous casting grade 20 steel billets are reduced to a great extent and qualification rate is enhanced from 60% to 80%.

关键词： tundish flow phenomena numerical simulation optimum

LINEAR POLYMERIZATION OF THE S-SULPHONATE OF THE B-CHAIN OF INSULIN Ⅰ. phenomena

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Science in China Series A:Mathematics 1963年第1期 83-100页

作者：鲁子賢曹天欽 Institute of Biochemistry Academia Sinica Shanghai Institute of Biochemistry Academia Sinica Shanghai

关键词： LINEAR POLYMERIZATION OF THE S-SULPHONATE OF THE B-CHAIN OF INSULIN phenomena

Uncommon and Impact-Suspicious Geologic phenomena across Jordan and Adjacent Areas, Arabian Plate

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Open Journal of Geology 2014年第12期4卷 680-717页

作者： Werner Schneider Elias Salameh Im Ziegenforth 15 D-38108 Braunschweig Germany Faculty of Science University of Jordan Amman Jordan

For the discovery and analysis of Jebel Waqf as Suwwan (JWS) Impact Crater, Jordan pushed the authors to consequently focusing on other unusual geologic phenomena such as circular/oval structures (some of “crypto-volcanic” origin), disharmonic folding, horizontal stylolites, and a broad stripe of?Sanidine-Hornfels-Facies, all of them hosted in Upper Cretaceous/Paleogene carbonate rocks exposed across Jordan and adjacent areas. Shatter cones are the most useful tools during field work in the realm of circular structures. In addition to the impact-geologic data of JWS Impact Structure hitherto available, the cooling process of melted Lower Cretaceous Kurnub-Sandstone could be verified by microscopically identified SiO2-modifications between the melting point (1714°C) and low temperatures. In comparison with the Suffield 500 tons explosion tests [20] and with the Ries Impact Crater, Germany, excavation and vaporization processes of target rocks demand drilling between Central Uplift and Inner Ring of the JWS Impact Structure (“Chert-Carbonate-Impact-Chess Game”). In a scenario: “Impacting meets Plate Tectonics”, phenomena like disharmonic folding, horizontal stylolites, and an abundance of circular/oval structures of high diameter variation through northwest Jordan are discussed under aspects of gravitational gliding, effects of seismic surface waves (Love-), transpressional structures related to Jordan Rift-Tectonics, and possible impact processes of unknown number occurred on the Arabian Plate in southeastern direction with northwest-directed impulse. The so-called “Mottled Zone” of Jordan and Palestine owning a high number (~100) of mineral neoformations with formation temperatures up to ~1120°C(pseudo-wollastonite = β-CaSiO3), is to be interpreted as of “Sanidine-Hornfels-Impact Facies” under ricochet conditions along an “Avenue of Ricochet-Impact-Thermo-Cataclysm”. Marble-related travertines represent a low temperature facies of the impact event. The temporal proj

关键词： Impact-Suspicious phenomena Ricochet Impact Impact-Related SiO2-Modifications Sanidine-Hornfels-Impact Facies Rapid Climate Change Holocene Hoyle’s Comet Rise and Fall of Neolithic/Bronze Age Cultures Coincidence of Natural and Cultural Evidence Jordan

An Analysis of the Cultural phenomena in Translation of Public Signs

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海外英语 2010年第6X期 213-214页

作者：张艳商丘师范学院外语学院河南商丘476000

This research focuses on several aspects of the translation of public signs from the perspective of cross-cultural *** discusses the existing problems and possible causes for Chinese-English translation of public sign... 详细信息

关键词： cultural phenomena public signs translation

Numerical Modeling of the Coupled Electromagnetic and Mechanical phenomena of Linear Stepping Motors

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Journal of Electromagnetic Analysis and Applications 2012年第1期4卷 1-8页

作者： Mustapha Zaouia Nacereddine Benamrouche M'hemed Rachek 不详

In this paper, we propose an electromagnetic-mechanical model based on the finite element and Macro-Element (ME) technique to analyse and study the dynamic characteristics of a Tubular Linear Switched Reluctance Stepping Motor (LSRSM). After the resolution of the non-linear electromagnetic equation governing the behaviour of the different materials of the motor using the nodal-based finite element method, this equation is then coupled to the mechanical equation firstly through the magnetic force computed by Maxwell stress tensor, and secondly by the modified flux distribution due to the moving part. Because of the precision required in the mobile part displacement and the very small air gap of stepping motors, the simulation of the movement is assured by the Macro-Element (ME) technique compared to other movement techniques that present many disadvantages. The validity of the developed model is verified through the comparison of the computed displacement of the LSRSM moving part with those given experimentally [2]. The Results shows satisfactory agreement. The obtained dynamic characteristics, particularly the starting magnetic force, are obtained by considering two values of the supplying currents.

关键词： Numerical Modeling Electromagnetic-Mechanical phenomena Finite Element Movement Stepping Motors