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81.
在弹簧质量不能忽略的情况下,推导了n个弹簧串联系统的动能和弹性势能具体表达式,结果表明:n个串联弹簧系统的动能与每个弹簧自身质量、劲度系数密切相关;系统的弹性势能由n个串联弹簧的等效劲度系数和串联弹簧的总伸长量决定. 相似文献
82.
Nusselt number correlations for heat transfer to small spheres in thermal plasma flows 总被引:1,自引:0,他引:1
Seven different equations predicting heat transfer rates to small spheres in plasma flows are examined considering argon and nitrogan as plasma gases from 300 to 21,000 K at 1 atm. For argon there is a general consensus up to 9000 K, beyond which wide deviations in behavior occur. For nitrogen, the seven correlations are in good agreement up to 4000 K, but show substantial deviations beyond this value. Comparisons with the sparsely available experimental data are made for argon from 300 to 17,000 K and for nitrogen up to 5500 K. Disagreement between the various correlations and experiment can exceed one order of magnitude. 相似文献
83.
84.
For the methylsilsesquioxane film whose optical birefringence is almost zero, it was recently reported that its vertical thermal expansion coefficient (CTE) was approximately one order of magnitude larger than the lateral CTE. Though the birefringence is not an absolute predictor of anisotropic behavior, the discrepancy in both the CTEs was so remarkable that it was essential to investigate whether the anisotropy was intrinsic property or not. If the effect of Poisson's ratio is considered in the calculation of the vertical CTE and when elastic modulus measured by surface acoustic wave spectroscopy is used in the assessment of the lateral CTE, both the CTEs are coincident with each other. Therefore, it can be concluded that the discrepancy in the CTEs can be attributed to a higher in‐plane polymer chain orientation but it can also arise from the misleadingly assumed modulus and Poisson's ratio. © 2006 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 44: 3109–3120, 2006 相似文献
85.
用高密度等离子体模型可以计算出一整套输运参数,并且在很宽的等离子体温度和密度范围内有合理的精度,可广泛应用于Z箍缩等离子体、激光聚变和磁约束聚变等领域,并将这个模型计算出的各种输运参数拟合成了实用的公式。 相似文献
86.
In order to replace silicones in some of their biomedical applications, e.g. syringe lubrication, implants ets., a series of digermoxanes (R1R2R3Ge)2O (R = n–alkyl, aryl) were synthesized. These compounds are thermally stable oils; their viscosities, depending on the nature of substituents, lie in the range 1–72 cPo (mPa s) at 20°C. 相似文献
87.
詹毅 《应用数学学报(英文版)》1997,(2)
ThisresearchissupportedbytheNationalNaturalSciencesFoundationofChina.1.IntroductionInthispaper,weseektoestablishthecomparisonprinciple,regularity,ekistenceandsomegeometricpropertiesoftheinterfaceoftheviscositysolutionsforthefollowingfullynonlineardegenerateequations(Problem(C)):withFsatisfyingthefollowingassumptions:Fisdegenerateparabolic,i.e.F(q,X Y)5F(q,X),VY20,whereSadenotesthespaceofnxnsymmetricmatriceswiththeusualordering.wherellXlll~ItrX l ltrX--l,X~X X--,X 20,X--50,A,B20,p>2… 相似文献
88.
Yang Lingxia Ge Debiao Wei Bing 《International Journal of Infrared and Millimeter Waves》2003,24(11):1893-1897
A modified formulation for fringe component of diffraction coefficient is implemented to TD-EEC method. An example of diffraction by perfectly conducting plate is used to illustrate our scheme. Comparing with the FDTD results we observe that the improved expression for fringe component is more accurate than that of Michaeli's formulation. This high frequency time domain technique is available for treating the bistatic scattering problems for millimeter waves. 相似文献
89.
G. A. Kohring 《Journal of statistical physics》1992,66(3-4):1177-1184
A hydrodynamic cellular automata (HDCA) for simulating two-dimensional fluids with large viscosities is proposed. The model is characterized by a mean free path which is of the same size as in the FHP-II model, but with a viscosity more than 10 times larger. This new model should make simulations of flows at low Reynolds number more efficient. 相似文献
90.
P. Terech 《Il Nuovo Cimento D》1994,16(7):757-764
Summary Viscoelastic solutions of a binuclear copper(II) tetracarboxylate (Cu2S8) in tert-butylcyclohexane (TBC) have been investigated by rheology and small-angle neutron scattering techniques. The data
are analysed in the theoretical framework of the so-called ?living polymers?. The Cu2S8 aggregates are semi-rigid thin heterogeneous molecular threads undergoing scission/recombination reactions. Structural and
dynamical correlations have been made with the thermotropic columnar phase and some lyotropic swollen mesophases of the system.
The simplicity of the composition and structural constitution enables to avoid the usual salt and composition problems of
the aqueous analogues and also to deduce some most probable behaviours related to the scission mechanisms, chain flexibility
and dynamics of stress relaxation.
Paper presented at the I International Conference on Scaling Concepts and Complex Fluids, Copanello, Italy, July 4–8, 1994.
Member of CNRS. 相似文献