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71.
Kishor S. Adhav Abhijit S. Bansod Rajesh P. Wankhade Hanumant G. Ajmire 《Central European Journal of Physics》2011,9(4):919-925
The exact solutions of the Einstein field equations for dark energy in Kantowski-Sachs metric under the assumption on the
anisotropy of the fluid are obtained for exponential and power-law volumetric expansions. The isotropy of the fluid, space
and expansion are examined. 相似文献
72.
73.
74.
Annals of Operations Research - Supply chain risk management embroils quite a lot of situations of managerial decision-making under uncertainties. As contemporary supply chains are intricate... 相似文献
75.
Kumar Sunil Jeon H. C. Kang T. W. Kalia Rajesh Sharma J. K. Panwar Sanjay Kalia Sapna Sharma Vandana Choubey R. K. 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2017,91(13):2666-2670
Russian Journal of Physical Chemistry A - In the present work, the effect of temperature and moisture has been studied on nano-porous polycarbonate membranes of size 15, 50, and 80 nm, respectively... 相似文献
76.
In this article, we study the homogenization of the family of parabolic equations over periodically perforated domains
. Here, Ωɛ=ΩS
ɛ is a periodically perforated domain. We obtain the homogenized equation and corrector results. The homogenization of the
equations on a fixed domain was studied by the authors [15]. The homogenization for a fixed domain and
has been done by Jian [11]. 相似文献
77.
We study the phenomenon of gyroscopic precession and the analogues of inertial forces within the framework of general relativity. Covariant connections between the two are established for circular orbits in stationary spacetimes with axial symmetry. Specializing to static spacetimes, we prove that gyroscopic precession and centrifugal force both reverse at the photon orbits. Simultaneous non-reversal of these in the case of stationary spacetimes is discussed. Further insight is gained in the case of static spacetime by considering the phenomena in a spacetime conformal to the original one. Gravi-electric and gravi-magnetic fields are studied and their relation to inertial forces is established. 相似文献
78.
A new bis-andrographolide ether from Andrographis paniculata nees and evaluation of anti-HIV activity 总被引:3,自引:0,他引:3
Reddy VL Reddy SM Ravikanth V Krishnaiah P Goud TV Rao TP Ram TS Gonnade RG Bhadbhade M Venkateswarlu Y 《Natural product research》2005,19(3):223-230
Novel bis-andrographolide ether (1) and six known compounds andrographolide, 14-deoxy-11,12-didehydroandrographolide, andrograpanin, 14-deoxyandrographolide, (+/-)-5-hydroxy-7,8-dimethoxyflavanone, and 5-hydroxy-7,8-dimethoxyflavone have been isolated from the aerial parts of Andrographis paniculata and their structures were established by spectral data. All the isolates were tested for the anti-HIV and cytotoxic activity. 相似文献
79.
We describe a model of cluster aggregation with a source which provides a rare example of an analytically tractable turbulent system. The steady state is characterized by a constant mass flux from small masses to large. Thus it can be studied using a phenomenological theory, inspired by Kolmogorov's 1941 theory, which assumes constant flux and self-similarity. We prove that such self-similarity is violated in dimensions less than or equal to two. We then use dynamical renormalization group techniques to show that the scaling of multipoint correlation functions implies nontrivial multifractality. The analytical results are supported by Monte Carlo simulations. 相似文献
80.
An integral approach to phase measurement is presented. First, the use of a high-resolution technique for the pixelwise detection of phase steps is proposed. Next, the robustness of the algorithm that is developed is improved by incorporation of a denoising procedure during spectral estimation. The pixelwise knowledge of phase steps is then applied to the Vandermonde system of equations for retrieval of phase values at each pixel point. Conceptually, our proposal involves the design of an annihilating filter that has zeros at the frequencies associated with the polynomial that describes the fringe intensity. The parametric estimation of this annihilating filter yields the desired spectral information embedded in the signal, which in our case represents the phase steps. The proposed method offers the advantage of extracting the interference phase of nonsinusoidal waveforms in the presence of miscalibration error of the piezoelectric transducer. In addition, in contrast to previously reported methods, this method does not require the application of selective phase steps between data frames for nonsinusoidal waveforms. 相似文献