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111.
The nondegenerative elliptic function solutions of some nonlinear equations are obtained by a nonlinear transform, which names the Jacobi elliptic function expansion. When taking particular parameters, the elliptic function solutions can degenerate as solitary wave solutions and singularity solutions. 相似文献
112.
MA Jianhua LIN Weizhen WANG Wenfeng & YAO Side . College of Biology Engineering Jimei University Xiamen China . Shanghai Institute of Applied Physics Chinese Academy of Sciences Shanghai China 《中国科学B辑(英文版)》2005,48(5):476-480
Many processes in organisms are involved in elec-tron transfer reaction, and radioactive effect, preven-tion and sensitization of radioactive injury are in-volved in it too. There exists a quantitative relation-ship between one-electron reduction potentia… 相似文献
113.
《Tetrahedron: Asymmetry》2006,17(3):320-323
Benzaldehyde was converted into enantiomerically pure (S)-mandelic acid by sequential HCN addition and hydrolysis in the presence of a cross-linked enzyme aggregate composed of the (S)-selective oxynitrilase from Manihot esculenta and the non-selective recombinant nitrilase from Pseudomonas fluorescens EBC 191. Surprisingly, (S)-mandelic amide was formed in large amounts. It was shown, in separate experiments, that the nitrilase hydrolyses (S)-mandelonitrile into an approx. equimolar mixture of acid and amide, whereas with the (R)-enantiomer only 10% of amide was formed. 相似文献
114.
Chen Zhangxu Fu Ming-Lai Huang Xiao-Dan Yuan Baoling Yang Jia-Cheng E. 《Research on Chemical Intermediates》2018,44(10):6369-6385
Research on Chemical Intermediates - To enhance photocatalytic activity spectra area of the TiO2 based photocatalyst, and to separate and recycle photocatalyst easily, magnetic photocatalyst was... 相似文献
115.
A new copper compound constructed from H2 Pmal (phenylmalonic acid), Dadm (4,4-diaminodiphenylmethane) and Cu(Ⅱ) has been synthesized from H2O-EtOH-DMF solution, and is characterized by X-ray single-crystal diffraction and other measurements. The compound crystallizes in the monoclinic system, space group C2/c with a=13.7866(6), b=10.1557(4), c=30.9036(17), β=101.422(5)o, V=4241.2(3)3 , Z=4, Dc=1.547g/cm3 , Mr=987.94, F(000)=2056, μ(MoKα)=1.078 mm-1 , S=1.007, R=0.0453 and wR=0.987 for 2806 observed reflections (I>2σ (I)). The title compound is characteristic of the cyclic dimeric molecules which further aggregate through hydrogen bonds and π-π interactions to form a 3-D supramolecular network. The microbial activities of the title compound and its reagents are investigated with filter paper discs diffusion method. The results show that the activity of the title compound is slightly better than its precursor reagents. 相似文献
116.
研究了孔雀石绿、高锰酸钾和甲醛对褶皱臂尾轮虫的急性毒性.结果表明:孔雀石绿、高锰酸钾和甲醛溶液对褶皱臂尾轮虫的毒性作用随浓度的增加而变大,这三种药物对褶皱臂尾轮虫的急性毒性顺序为:孔雀石绿>高锰酸钾>甲醛;孔雀石绿、高锰酸钾和甲醛对褶皱臂尾轮虫24 h的LC50分别是0.613 mg·L-1、0.873 mg·L-1和11.277 mg·L-1,其相应的安全浓度分别为6.13 μg·L-1、8.73 μg·L-1和112.77 μg·L-1. 相似文献
117.
研究锥伪单调、锥拟凸和上锥连续映射在某种强制性条件下的向量均衡问题解集的特征,建立强制性条件与向量均衡问题解集的关系,得到对偶向量均衡问题局部解集含于向量均衡问题解集的性质和向量均衡问题解集的非空性条件,给出在锥伪单调、锥拟凸和上锥连续映射条件下向量均衡问题解集的非空有界性与强制性条件的等价性. 相似文献
118.
本文考虑了一类食饵具有流行病和阶段结构的脉冲时滞捕食模型.利用脉冲时滞微分方程的相关理论和方法,获得易感害虫根除周期解全局吸引的充分条件以及当脉冲周期在一定范围内时,天敌与易感害虫可以共存且易感害虫的密度可以控制在经济危害水平E(EIL)之下.我们的结论为现实的害虫管理提供了可靠的策略依据. 相似文献
119.
Shui-Li Chen Guo-Long Chen Jian-Cheng Zhang 《Fuzzy Optimization and Decision Making》2008,7(4):351-360
In this paper, an ω-convergence theory of filters in an Lω-space is established. By means of the ω-convergence theory, some important characterizations with respective to the ω-closed sets, ω
T
2 separation and (ω
1, ω
2)-continuous mappings are obtained. Moreover, the mutual relationships among ω-convergence of molecular nets, ω-convergence of ideals and ω-convergence of filters are given. 相似文献
120.
《力学快报》2022,12(5):100364
As a promising vibration control device, the vibro-impact nonlinear energy sink (VI-NES) gathered extensively attention in recent years. However, general optimization procedures have not been available for the design of VI-NES subjected to random excitations. To this end, this paper constitutes a research effort to address this gap. Specifically, the approximate analytical solution of the system stochastic response is obtained in conjunction with non-smooth conversion and stochastic averaging methodology. Taking advantages of this approximate solution, the variance of the system is defined and easily minimized to calculate the optimal parameters for VI-NES. In addition, the results computed by this way fairly correlate with direct numeric simulations. 相似文献