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1.
Dynamical analysis,circuit realization,and application in pseudorandom number generators of a fractional-order laser chaotic system 下载免费PDF全文
Chenguang Ma 《中国物理 B》2021,30(12):120504-120504
A new five-dimensional fractional-order laser chaotic system (FOLCS) is constructed by incorporating complex variables and fractional calculus into a Lorentz-Haken-type laser system. Dynamical behavior of the system, circuit realization and application in pseudorandom number generators are studied. Many types of multi-stable states are discovered in the system. Interestingly, there are two types of state transition phenomena in the system, one is the chaotic state degenerates to a periodical state, and the other is the intermittent chaotic oscillation. In addition, the complexity of the system when two parameters change simultaneously is measured by the spectral entropy algorithm. Moreover, a digital circuit is design and the chaotic oscillation behaviors of the system are verified on this circuit. Finally, a pseudo-random sequence generator is designed using the FOLCS, and the statistical characteristics of the generated pseudo-random sequence are tested with the NIST-800-22. This study enriches the research on the dynamics and applications of FOLCS. 相似文献
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《数学季刊》2017,(2):194-207
In this paper, by means of the dual Brunn-Minkowski theories and methods as well as the integral transform, we have established a stability version of nonsymmetric convex bodies from intersection bodies. In addition, a stability results of symmetric convex bodies from Lp-counterparts is established. 相似文献
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用密度泛函理论在B3LYP/6-311++G(2d,2P)计算水平上对硝基甲烷分子进行了结构优化、频率和热化学分析.发现:在相同温度条件下改变压强,分子熵函数产生了改变,当温度和压强条件相同时,对于不同物质熵函数的改变是相同的.以热力学理论中麦克斯韦关系为基础,通过计算等温过程中分子的熵函数对压强的变化率,用数值拟合方法得到不同压强条件下分子温度的表达式:T=T0+(1-B)[18.3858+0.5392P]V0,式中T0、V0分别表示分子系统初态的温度和体积,T、V分别表示系统在末态的温度和体积,B是体积的压缩比.在选定参数的情况下该表达式可以计算不同压强条件下CHNO含能材料的分子温度.同时,以硝基甲烷为验证,选取基本参数V0和B,计算其在C-J条件对应的爆压14GPa下,分子温度为3461K,对应爱因斯坦温度,相当于3228cm-1的能量,在实验中该能量足以激发硝基甲烷分子内振动能量重新分配过程,有可能激发C-N键的红外振动而引起单分子分解反应的发生.因此,此表达式可用于预测含能材料撞击点火过程单分子分解可能的反应通道. 相似文献
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Youneng Guo Maofa Fang Shiyang Zhang Jiang Huang Xiang Liu 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2014,68(11):1-7
The nonlinear interaction between electron-acoustic shock waves in a dissipative, non-Maxwellian plasma composed of cold fluid electrons, stationary background ions, and inertialess superthermal electrons has been studied. The effects of plasma parameters on the trajectory changes (i.e., phase shifts) of shock waves after their head-on collision is our main concern. The results indicate that the interactions between shocks are different from those of solitons. Also, it is found that the occurrence and variation of trajectory shifts may be due to the combined role played by the dispersion and dissipation of the colliding nonlinear structure. 相似文献
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Junhua Luo Fei Tuo Xiangzhong Kong 《Journal of Radioanalytical and Nuclear Chemistry》2011,288(1):143-148
The cross sections for formation of metastable state of 178Hf (178m2Hf, 574.215 keV, 31 y) and 179Hf (179m2Hf, 362.55 keV, 25.05 d) through reactions induced by 14.8 ± 0.2 MeV neutrons on natural hafnium were measured for the first
time. The monoenergetic neutron beam was produced via the 3H(d, n)4He reaction on ZF-300-II Intense Neutron Generator at Lanzhou University. Induced gamma activities were measured by a gamma-ray
spectrometer with high-purity germanium (HPGe) detector. Measurements were corrected for gamma-ray attenuations, random coincidence
(pile-up), dead time and fluctuation of neutron flux. The neutron fluence were determined by the cross section of 93Nb(n, 2n)92mNb reaction. The neutron energy in the measurement were by the cross section ratios of 90Zr(n, 2n)89m+gZr and 93Nb(n, 2n)92mNb reactions. 相似文献
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Junhua Luo Rong Liu Li Jiang Zhenlai Liu 《Journal of Radioanalytical and Nuclear Chemistry》2011,289(2):455-459
Cross-sections for (n,2n), (n,p), (n,α), and (n,d*) (The expression (n,d*) cross section used in this work includes a sum
of (n, d), (n, np) and (n, pn) cross sections) reactions have been measured on erbium isotopes at the neutron energies from
13.5 to 14.8 MeV using the activation technique in combination with high-resolution gamma-ray spectroscopy. Data are reported
for the following reactions: 162Er(n,2n)161Er, 164Er(n,2n)163Er, 168Er(n,α)165mDy, 166Er(n,p)166gHo, 170Er(n,α)167Dy, 168Er(n,p)168m+gHo, 170Er(n,p)170gHo, and 170Er(n,d*)169Ho. The cross sections were discussed and compared with experimental data found in the literature, and with the comprehensive
evaluation data in ENDF/B-VII.0 and l JEFF-3.1/A libraries. 相似文献
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设计合成了新型烯醇-酮互变异构型亚胺衍生物R, 考察了受体R对18种阳离子的紫外光谱及裸眼识别性能. 结果表明, 该受体对Co2+, Fe2+和Ni2+表现出良好的紫外光谱识别能力, 且可实现对Co2+相对明显的裸眼单一识别. Job曲线表明, 受体R与Co2+形成了1:1型金属配合物, 且检出限可达4.14×10-7 mol/L. 制备了受体R裸眼比色识别试纸; 根据理论计算及核磁滴定实验结果阐述了Co2+离子识别过程中烯醇-酮互变异构机理. 相似文献