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IntroductionMuchworkhasbeendevotedinthelastfewdecadestothemeasurementandmodelingofthescalinglawofstructurefunctionofturbulentflows.Theso_called“velocitystructurefunctionofordern”forturbulentflowsisdefinedas〈ΔV(r) n〉 ,whereΔV(r) =V(x r) -V(x)isthevelocitycomp…  相似文献   
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The experimental study is conducted to clarify the functional enhancement of a non-equilibrium argon plasma jet by seeding potassium in the applied magnetic field to extend its industrial applications. It is shown that the plasma parameters such as electron number density and electron temperature increase considerably by seeding especially in the applied magnetic field, which results in the easy enhancement of transport properties such as electrical conductivity and electron thermal conductivity. Finally, the infrared thermography is shown to visualize the relative variation of radiative temperature field comparing both with seeding and without seeding.  相似文献   
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IntroductionManymechanicalsystemscanbeviewedaslinearHamiltoniansystems.Whenwestudytheeffectsofsystemparametersonthebehaviorofthesystems,thesystemcanberegardedasthesystemdependingonparameters.Veryimportantsystemparameters ,suchascriticalload ,criticalang…  相似文献   
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On the basis of the sufficient consideration of vectorial characteristics of stress, a new nonlinear constitutive model for cohesionless soil under plane strain and 3-D conditions was presented in a way that the action effects of stress vector are decomposed into the action effect of mean effective stress and that of the stress ratio vector (ratio of deviatoric stress vector to mean effective stress). The constitutive model can take account of the influence of both numerical and directional changes of stress vector on deformation of soil simultaneously, and is applicable of both static and dynamic loading. Biography: Shi Hong-yan (1964-)  相似文献   
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Two novel lanthanide‐based coordination polymers with 2D lattice‐type motif, [Ln2(CAM)3(H2O)4]·2H2O (CAM = 4‐Hydroxypyridine‐2,6‐dicarboxylate; Ln = Tb( 1 ), Pr( 2 )), have been prepared by hydrothermal reaction of Ln(OH)3, CAM and water at 160 °C and characterized by single‐crystal X‐ray diffraction analysis, IR and TGA. The investigation of luminescent property reveals that 1 exhibits characteristic green emission of Tb3+ ions.  相似文献   
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A semi-analytical and semi-numerical method is proposed for the dynamic analysis of foundations. The Lamb's solution and the approximate formulae were used to establish the relation of the contact force and deflection between the foundation and soil. Therefore, the foundation can be separated from soil and analyzed by FEM as for the static cases. The plate can be treated as that the known forces are acting on the upper surface, and the contact pressure from soil can be represented as the deflection. So that only the plate needs to be divided into elements in the analysis. By this method, a series of vibration problems, including various shapes and rigidities of foundations, different excitation frequencies, were analyzed. Furthermore, it can be used for the embedded foundation. The numerical examples show that this method has simplicity, highly accurate and versatile. It is an effective method for the dynamic analysis of foundations.  相似文献   
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