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1.
Hua Nie Jian-hua Wu 《应用数学学报(英文版)》2006,22(2):257-264
This paper is concerned with the unstirred chemostat model with two-species and one non-reproducingresource.The global attractivity of the positive steady-state solutions of the original system is established.Moreover,the effects of the growth rate on the unique positive equilibrium of the single population model arestudied. 相似文献
2.
3.
双包层椭圆光波导解析解 总被引:3,自引:0,他引:3
解析求解了双包层椭圆光纤中的波动方程,得到了模式精确解有模式特征方程。对基模的特征方程进行了数值计算,给出了不同椭圆比下的归一化双折射和模间色散随归一化频率的变化关系曲线,并与高斯近似解的结果进行了比较。 相似文献
4.
I. R. Gulamov A. A. Karakhodzhaev A. M. Mukhamedzhanov G. K. Nie E. A. Pak R. Yarmukhamedov V. Burjan J. Cejpek V. Kroha J. Křemének M. Kurka 《Czechoslovak Journal of Physics》1990,40(8):875-894
The angular distributions of the (p, d), (d, t) and(3He, ) reactions on13C have been analysed within the framework of DWBA in which additional information on nuclear vertex constants was introduced. Although all these reactions seem to be similar single nucleon transfer, their mechanism is shown to be quite different and so is the information extracted thereof. While from the (p, d) reactions spectroscopic factors may be extracted unambiguously, from the (d, t) reactions it is possible to obtain directly the values of vertex constants only, which in turn are consistent with those determined by extrapolation of the experimental cross sections of the (p, d) reactions to the pole.In the case of (3He, ) reactions, however, the analysis indicates inadequacy of the DWBA concerning the calculations of central partial amplitudes. For a more reliable extraction of structural information, besides the correct normalization of peripheral amplitudes, a contribution of more complex mechanisms must be taken into account. 相似文献
5.
In this paper, a natural R
+
n+1
extension of singular integrals, i.e.,T
κ:f→K*φ
t
*t with K a standard C-Z kernel and ϕ usual one, is investigated. One of the main results is: Let (dμ, udx) ∈C1 and u-Mw, w∈A∞, then Tk is of type (Lp(udx), Lp(dμ)). As a related topic, a maximal operator
is proved to be of type
, where
, provided (dμ, udx) ∈C1 and u∈ A∞.
Supported by National Science Foundation of China 相似文献
6.
S. A. Goncharov A. M. Mukhamedzhanov E. A. Romanovskii G. E. Valiev I. R. Gulamov Yu. I. Denisov T. Iskhakov A. Karakhodzhaev G. K. Nie R. Yarmuchamedov V. A. Stepanenko V. Kroha 《Czechoslovak Journal of Physics》1988,38(1):12-18
The differential cross sections of tritons from the (d, t) reaction on9Be,10B and13C targets have been measured in the angular range of 5°
LAB110° with relatively small errors, 5%. The experimental data were analysed in terms of the standard DWBA using both zero-range and exact finite-range approaches. 相似文献
7.
8.
Ying Wang Pu Xiao Gang Qiang Wu Su Qing Shi Jun Nie 《中国化学快报》2007,18(8):977-980
A benzophenone derivative photoinitiator, HBP-TDI-HQ-TDI-HBP (HTCTH), was synthesized based on 4-hydroxy benzophenone (HBP), toluene-2,4-diisocyanate (TDI) and hydroquinone (HQ). HTCTH was a more effective photoinitiator which had longer wavelength absorption in the UV-vis absorption spectra than the low molecular counterpart benzophenone (BP). It showed that both rate of polymerization (Rp) and final conversion (P) increased with increase of amine and HTCTH concentration in photopolymerization. 相似文献
9.
10.
A new quartz crystal impedance sensing technique for the assay of hyaluronidase (HAse) activity is presented. It is based on the changes in viscosity and density during the enzymatic hydrolysis of hyaluronic acid (HA) by HAse. The variations of equivalent circuit parameters of piezoelectric quartz crystal (PQC) during the enzymatic degradation are discussed. The motional resistance shift curves indicate that the viscosity of the test solutions decreases during the hydrolysis process. The initial hydrolysis rates of HA are obtained from changes in viscosity and density as a function of incubation time. Kinetic parameters (the Michaelis constant K(m) and the maximum hydrolysis rate V(max)) of the degradation reaction are estimated by using a linear Lineweaver-Burk plot in this work. The K(m) was 0.44+/-0.03 mg.ml(-1) and the V(max) was -(5.29+/-0.36)x10(-3) kg.m(-2).s(-1/2).min(-1). 相似文献