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11.
Resonance width, shift in resonance frequency, relaxation time and activation energy of 5CB nematic liquid crystal are measured
using microwave cavity technique under the influence of an external magnetic field at 9 GHz and at different temperatures.
The dielectric response in liquid crystal at different temperatures and the effects of applied magnetic field on transition
temperatures are studied in the present work. The technique needs a small quantity (< 0.001 cm3) of the sample and provides fruitful information about the macroscopic structure of the liquid crystal. 相似文献
12.
PRASHANT SINGH RUDRA BANERJEE MOSHIOUR RAHAMAN A V RUBAN BIPLAB SANYAL ABHIJIT MOOKERJEE 《Pramana》2011,76(4):639-656
We study the electronic structure and a mean-field phase analysis based on the pair–pair energies derived from first-principles
electronic structure calculations of AuFe and NiMo alloys. We have used the tight-binding linear muffin-tin orbitals-based
augmented space recursion (TB-LMTO-ASR) method to do so. We investigate different behaviours of the two alloy systems by mapping
the problems onto equivalent Ising models and then discuss the magnetic phase diagrams using the calculated pair energies.
All three phases: paramagnetic, random ferromagnetic and spin glass, have been studied. 相似文献
13.
Primordial black holes evaporate due to Hawking radiation. We find that the evaporation times of primordial black holes increase
when accretion of radiation is included. Thus, depending on accretion efficiency, more primordial black holes are existing
today, which strengthens the conjecture that the primordial black holes are the proper candidates for dark matter. 相似文献
14.
We study the interplay of topology and dynamics of excitable nodes on random networks. Comparison is made between systems
grown by purely random (Erdős–Rényi) rules and those grown by the Achlioptas process. For a given size, the growth mechanism
affects both the thresholds for the emergence of different structural features as well as the level of dynamical activity
supported on the network. 相似文献
15.
In this paper,the basic equations governing the flow and heat transfer of an incompressible viscous and electrically conducting fluid past a semi-infinite vertical permeable plate in the form of partia... 相似文献
16.
Let (S,ω) be a weighted abelian semigroup, let M ω (S) be the semigroup of ω-bounded multipliers of S, and let \(\mathcal {A}\) be a strictly convex commutative Banach algebra with identity. It is shown that T is an onto isometric multiplier of \(\ell ^{1}(S,\omega , \mathcal {A})\) if and only if there exists an invertible σ ∈ M ω (S), a unitary point \(a \in \mathcal {A}\), and a k>0 such that \(T(f)= ka{\sum }_{x \in S} f(x)\delta _{\sigma (x)}\) for each \(f={\sum }_{x \in S}f(x)\delta _{x} \in \ell ^{1}(S,\omega ,\mathcal {A})\). It is also shown that an isomorphism from \(\ell ^{1}(S_{1},\omega _{1},\mathcal {A})\) onto \(\ell ^{1}(S_{2},\omega _{2}, \mathcal {B})\) induces an isomorphism from \(M(\ell ^{1}(S_{1},\omega _{1},\mathcal {A}))\), the set of all multipliers of \(\ell ^{1}(S_{1},\omega _{1},\mathcal {A})\), onto \(M(\ell ^{1}(S_{2},\omega _{2},\mathcal {B}))\). 相似文献
17.
C P ANIL KUMAR 《Proceedings Mathematical Sciences》2017,127(1):69-90
Many questions about triangles and quadrilaterals with rational sides, diagonals and areas can be reduced to solving certain diophantine equations. We look at a number of such questions including the question of approximating arbitrary triangles and quadrilaterals by those with rational sides, diagonals and areas. We transform these problems into questions on the existence of infinitely many rational solutions on a two parameter family of quartic curves. This is further transformed to a two parameter family of elliptic curves to deduce our main result concerning density of points on a line which are at a rational distance from three collinear points (Theorem 4). We deduce from this a new proof of density of rational quadrilaterals in the space of all quadrilaterals (Theorem 39). The other main result (Theorem 3) of this article is on the density of rational triangles which is related to analyzing rational points on the unit circle. Interestingly, this enables us to deduce that parallelograms with rational sides and area are dense in the class of all parallelograms. We also give a criterion for density of certain sets in topological spaces using local product structure and prove the density Theorem 6 in the appendix section. An application of this proves the density of rational points as stated in Theorem 31. 相似文献
18.
PAVINDER SINGH 《Proceedings Mathematical Sciences》2011,121(3):259-265
The aim of this article is to study the homological properties of deficiently extremal Gorenstein algebras. We prove that
if R/I is an odd deficiently extremal Gorenstein algebra with pure minimal free resolution, then the codimension of R/I must be odd. As an application, the structure of pure minimal free resolution of a nearly extremal Gorenstein algebra is
obtained. 相似文献
19.
S.K. SHARMA ASHIM KUMAR ROY D.J. SOMERFORD 《Journal of Quantitative Spectroscopy & Radiative Transfer》1998,60(6):1001-1010
We present two new phase functions, one for particles small compared to the wavelength of the scattering radiation and the other for particles large compared to the wavelength of the scattering radiation. These phase functions have been validated for the case of Mie scatterers. For small particles, the results of the new phase function are found to be identical with the Mie results. For large particles, comparison with the Mie results show that the phase function presented here is an extremely good approximation to the Mie phase function. We believe that these phase functions can be expediently used in problems relating to solutions of the radiative transfer equations. 相似文献
20.