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91.
Pulsatile flow of blood through mild stenosed narrow arteries is analyzed by treating the blood in the core region as a Casson fluid and the plasma in the peripheral layer as a Newtonian fluid. Perturbation method is used to solve the coupled implicit system of non-linear differential equations. The expressions for velocity, wall shear stress, plug core radius, flow rate and resistance to flow are obtained. The effects of pulsatility, stenosis, peripheral layer and non-Newtonian behavior of blood on these flow quantities are discussed. It is found that the pressure drop, plug core radius, wall shear stress and resistance to flow increase with the increase of the yield stress or stenosis size while all other parameters held constant. The percentage of increase in the resistance to flow over the uniform diameter tube is considerably very low for the present two-fluid model compared with those of the single-fluid model.  相似文献   
92.
In this article,we prove that the symmetric function F_n~*(x,r)=i_1+i_ 2_++i_n =r(x_1~(i~1)x_2~(i~2)... x_n~(i~n)1/r is Schur harmonic convex for x∈R~n_+and r∈N={1,2,3,...}.As its applications,some analytic inequalities are established.  相似文献   
93.
In this paper, the Hermitian positive definite solutions of the nonlinear matrix equation X^s - A^*X^-tA = Q are studied, where Q is a Hermitian positive definite matrix, s and t are positive integers. The existence of a Hermitian positive definite solution is proved. A sufficient condition for the equation to have a unique Hermitian positive definite solution is given. Some estimates of the Hermitian positive definite solutions are obtained. Moreover, two perturbation bounds for the Hermitian positive definite solutions are derived and the results are illustrated by some numerical examples.  相似文献   
94.
讨论了具有散度偏大特征计数数据的建模与拟合问题.针对导致数据散度偏大的原因和常用的几类候选模型的结构,分别给出了关于嵌套模型的模型与变量同时选择的Bayes方法和关于非嵌套模型的模型检验与比较方法,并在此基础上进一步完善,提出了较为系统完整的模型与变量选择方法.实际例子说明了方法的具体实现过程和有效性.  相似文献   
95.
主要讨论了Hardy-Littlewood极大函数,Sharp极大函数以及分数次极大函数与BMO(R~n)函数生成的交换子在广义Morrey空间上有界性的等价刻画.  相似文献   
96.
Let Ω be a bounded domain in Rnwith a smooth boundary, and let h p,q be the space of all harmonic functions with a finite mixed norm. The authors first obtain an equivalent norm on h p,q, with which the definition of Carleson type measures for h p,q is obtained. And also, the authors obtain the boundedness of the Bergman projection on h p,q which turns out the dual space of h p,q. As an application, the authors characterize the boundedness(and compactness) of Toeplitz operators T μ on h p,q for those positive finite Borel measures μ.  相似文献   
97.
Journal of Radioanalytical and Nuclear Chemistry - The effect of Bacillus spp. on Re(VII) and Se(IV) diffusion in compacted GMZ bentonite was investigated by a through-diffusion method. Bacillus...  相似文献   
98.
利用密度泛函理论(DFT)研究了M12Ni(M=Pt, Sn, Cu) 3种双金属合金团簇的电子活性和结构稳定性, 并探讨了甲烷干法重整反应(DRM)在M12Ni双金属团簇表面的反应能量变化情况. 经比较发现甲烷脱氢和二氧化碳活化过程在Pt12Ni团簇表面进行需克服的活化能垒最低, 反应最易进行. Sn12Ni团簇上生成碳需要较高的活化能, 说明Sn12Ni团簇能够有效抑制焦碳的生成, 一定程度上克服了碳沉积导致的催化剂失活现象, 并且Sn12Ni团簇在C *和CH *氧化过程中表现出最佳的催化活性. Cu12Ni团簇仅在甲烷脱氢过程中表现出较为优异的催化活性.  相似文献   
99.
The two-dimensional total routhian surface calculations have been carried out to stud), the triaxial superdeformed structure of a neutron-rich nucleus ^173 Hf firstly. In particular the effects of the rotational frequency ω and pairing-energy gap parameter A are discussed in detail in the course of shaping its triaxial superdeformation; additionally the neutron-shell correction energy is analyzed with emphasis in the confirmed triaxial superdeformed nucleus ^173Hf. Finally, more systematical results have been investigated for some confirmed superdeformed nuclei experimentally and a few predicted triaxial superdeformed nuclei theoretically with quadropole deformation ε2 ≈0.4 and triaxial deformation γ≈20° or 30° in the Z = 72 region.  相似文献   
100.
ZHANG Da-Li 《理论物理通讯》2008,50(12):1391-1395
Properties of the four rotation bands, ^157Er(1,2) and ^15SEr(1,2), at ultrahigh spin are investigated within the supersymmetry scheme including many-body interactions and possessing the SO(5) (or SU(5)) symmetry on the rotational symmetry. Quantitatively good results of the 7-ray energies and the dynamical moments of inertia in the rotation bands in ^157 Er and ^158 Er at ultrahigh spin are obtained. We theoretically predict that the competition between the anti-pairing and pairing effects may exist in ^157 Er(1,2) and ^158Et(2) bands states. In ^158Er(1) band state, the favourepairing effects may exist and the SO(5) (or SU(5)) symmetry play a dominant role. There may be sphere coexisting with headecupole deformed in ^158Et(1) rotation band state.  相似文献   
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