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81.
The purpose of the present note is to establish some new delay integral inequalities, which provide explicit bounds on unknown functions and generalize some results of Li et al. [Some new delay integral inequalities and their applications, J. Comput. Appl. Math. 180 (2005) 191–200]. The inequalities given here can be used to investigate the qualitative properties of certain delay differential equations and delay integral equations. 相似文献
82.
A uniqueness theorem for two distinct non-constant meromorphic functions that share three values of finite weights is proved, which generalizes two previous results by H.X. Yi, and X.M. Li and H.X. Yi. As applications of it, many known results by H.X. Yi and P. Li, etc. could be improved. Furthermore, with the concept of finite-weight sharing, extensions on Osgood-Yang's conjecture and Mues' conjecture, and a generalization of some prevenient results by M. Ozawa and H. Ueda, ect. could be obtained. 相似文献
83.
84.
In this paper, we study the growth of solutions of a first order linear differential equation. From this we verify that a
conjecture given by Brück is true under the restriction of the hyper order less than 1/2, and obtain some uniqueness theorems
of a nonconstant entire function and its first derivative sharing a nonzero constant CM. The results in this paper also improve
some known results. Some examples show that the results in this paper are best possible.
Project supported by the NSFC (NO. A0324617) and the RFDP (NO. 20060422049).
Received: 20 April 2006 Revised: 4 February 2007 相似文献
85.
带干扰的Erlang(2)风险模型的不破产概率 总被引:1,自引:0,他引:1
本文讨论了带干扰的Erlang(2)风险模型,通过构造一个延迟更新过程,我们得到了不破产概率满足的积分-微分方程,进而得到了不破产概率的明确表达式. 相似文献
86.
Large quantities of CaN nanorods are successfully synthesized on Si(111) substrates by ammoniating the films of Ga2O3/ZnO at 950℃ in a quartz tube. The structure, morphology and optical properties of the as-prepared CaN nanorods are studied by x-ray diffraction, scanning electron microscopy, high-resolution transmission electron microscopy, Fourier transform infrared spectroscopy, and photoluminescence. The results show that the CaN nanorods have a hexagonal wurtzite structure with lengths of several micrometres and diameters from 80 nm to 300hm, which could supply an attractive potential to harmonically incorporate future GaN optoelectronic devices into Si-based large-scale integrated circuits. The growth mechanism is also briefly discussed. 相似文献
87.
Protection of iron corrosion by stearic acid and stearic imidazoline self-assembled monolayers 总被引:4,自引:0,他引:4
A type of stearic imidazoline (IM) inhibitor was prepared using stearic acid (SA) and diethylenetriamine (DETA) as raw materials. The monolayers of IM and SA were assembled on the iron surface. The electrochemical characterization of stearic acid (SA) and stearic imidazoline (IM) on an oxide free iron surface had been studied. The monolayers of IM inhibitor were characterized by electrochemical impedance spectroscopy (EIS), electrochemical polarization curves, double layer capacitance, X-ray photoelectron spectroscopy (XPS) and molecular simulation. The results of electrochemical studies had illustrated that the inhibition efficiency of IM was higher than SA. XPS showed that the IM molecules adsorbed on the iron surface. The molecular simulation calculations showed that the IM molecules were tilted at an angle on the iron surface. 相似文献
88.
X.P. Hu X. Wang Z. Yan H.X. Li J.L. He S.N. Zhu 《Applied physics. B, Lasers and optics》2007,86(2):265-268
High power red light was generated from a periodically-poled stoichiometric LiTaO3 (PPSLT) by single-pass frequency doubling of a diode-side-pumped, Q-switched Nd:YAG laser at 1319 nm. An average power of
2.4 W of the 660 nm red light was obtained at the fundamental power of ∼5.4 W with the conversion efficiency up to 44.4% and
with low fluctuation down to 2%. The high efficiency and stability at the red output indicate that it is a practical method
to construct a reliable compact red laser.
PACS 42.70.Mp; 42.79.Nv; 42.55.Xi 相似文献
89.
《Physica A》2006,369(2):266-274
The Percus–Yevick equation is solved numerically for hard disks on a sphere. The effect of curvature of the hosting surface is calculated, and an empirical correction to the equation of state is proposed. 相似文献
90.
In this paper, the structure of cubic CaTiO3 (001) surfaces with CaO and TiO2 terminations has been studied from density functional calculations. It has been found that the Ca atom has the largest relaxation for both kinds of terminations, and the rumpling of the CaO-terminated surface is much larger than that of TiO2-terminated surface. Also we have found that the metal atom relaxes much more prominently than the O atom does in each layer. The CaO-terminated surface is slightly more energetically favourahle than the TiO2-terminated surface from the analysis of the calculated surface energy. 相似文献