The three bilinearities for functions are sharply estimated in function spaces associated to the Schrödinger operator . These bilinear estimates imply local wellposedness results for Schrödinger equations with quadratic nonlinearity. Improved bounds on the growth of spatial Sobolev norms of finite energy global-in-time and blow-up solutions of the cubic nonlinear Schrödinger equation (and certain generalizations) are also obtained.
In this paper we prove uniqueness of positive solutions to logistic singular problems , , 1$">, 0$"> in , where the main feature is the fact that . More importantly, we provide exact asymptotic estimates describing, in the form of a two-term expansion, the blow-up rate for the solutions near . This expansion involves both the distance function and the mean curvature of .
We consider the ( p , n m p ) right focal boundary value problem: $${\matrix{{(- 1)^{n - p} u^{(n)} \! = \lambda \;f(t, u), } \hfill & \ {{\rm for }\ 0 \lt t \lt 1, } \hfill \cr \quad \quad \,{u^{(i)} (0) = 0, } \hfill & {0 \le i \le p - 1, } \hfill \cr \quad \quad \,{u^{(i)} (1) = 0, } \hfill & {p \le i \le n - 1, } \hfill \cr}} $$ where 1 h p h n m 1 is fixed and u > 0. Using a fixed point theorem for operators on a cone, we develop criteria for the existence of positive solutions of the boundary value problem for u on a suitable interval. 相似文献
The effect of Fe-doping on the structural, morphological and optical properties of ZnO nanoparticles synthesized by simple solution combustion process are reported. The powder XRD pattern indicates that the Fe-doped ZnO samples exhibit primary and secondary phases. The primary phase indicates the hexagonal wurtzite structure with the average crystalline size of around 25–50 nm and the secondary phase is associated with the face centered cubic structure of magnetite iron oxide. The elemental composition of pure and Fe-doped samples are evaluvated by EDX. The results of FE-SEM and HR-TEM cleary show that particles morphology have changed with respect to the incorporation of doping agent and particles are in aggregating nature. The vibrational properties of the synthesized ZnO nanoparticles are investigated by Raman scattering technique and it exhibits that the influence of Fe-doping significantly modify the lattice vibrational characteristics in ZnO sites. The optical properties of the Fe-doped ZnO nanoparticles are carried out by UV–vis absorption and PL spectra. The results of PL spectra show the near-band edge related emission as well as strong blue emissions in the Fe-doped ZnO nanoparticles. 相似文献
This paper deals with the existence and nonexistence of global positive solution to a semilinear reaction-diffusion system with nonlinear boundary conditions.For the heat diffusion case,the necessary and sufficient conditions on the global existence of all positive solutions are obtained.For the general fast diffusion case,we get some conditions on the global existence and nonexistence of positive solutions.The results of this paper fill the some gaps which were left in this field. 相似文献
This present work narrates the stress stability behavior and development of a liquid chromatographic method for the quantitative
determination of anastrozole. Anastrozole is appropriately used when using substantial amounts of aromatizing steroids, or
when one is prone to gynecomastia and using moderate amounts of such steroids. A chromatographic separation was achieved on
a Hichrom RPB18 (250 × 4.6 mm, 5 μ) column using water and mixture of acetonitrile and methanol (1:1 ratio) as mobile phase.
Forced degradation studies were performed on bulk samples of anastrozole using acid, base, hydrogen peroxide, heat and UV
light. Degradation of the drug substance was observed in base hydrolysis. Degradation product formed under base hydrolysis
was found to be Imp-C. The sample solution and mobile phase were found to be stable up to 48 h. The developed method was validated
with respect to linearity, accuracy, precision, robustness and forced degradation studies prove the stability indicating power
of the method. 相似文献