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1.
Journal of Radioanalytical and Nuclear Chemistry - The simplified 8-oxide system (SiO2-B2O3-Na2O-Al2O3-CaO-TiO2-MoO3-La2O3) has been prepared under two types of cooling methods, and analyzed with...  相似文献   
2.
In this Letter,we report the existence and relaxation properties of a critical phenomenon on called a 3D super crystal that emerges at T=TC?3.5℃,that is,in the proximity of the Curie temperature of a Cu:KTN sample.The dynamics processes of a 3D super crystal manifest in its formation containing polarized nanometric regions and/or polarized clusters.However,with strong coupling and interaction of microcomponents,the characteristic relaxation time measured by dynamic light scattering demonstrates a fully new relaxation mechanism with a much longer relaxation time.As the relaxation mechanism of a relaxator is so-far undetermined,this research provides a novel perspective.These results can help structure a fundamental theory of ferroelectric relaxation.  相似文献   
3.
This paper is concerned with the problem of exponential stability for a class of impulsive nonlinear stochastic differential equations with mixed time delays. By applying the Lyapunov–Krasovskii functional, Dynkin formula and Razumikhin technique with a stochastic version as well as the linear matrix inequalities (LMIs) technique, some novel sufficient conditions are derived to ensure the exponential stability of the trivial solution in the mean square. The obtained results generalize and improve some recent results. In particular, our results are expressed in terms of LMIs, and thus they are more easily verified and applied in practice. Finally, a numerical example and its simulation are given to illustrate the theoretical results.  相似文献   
4.
By using the generalized Riccati transformation and the inequality technique, we establish some new oscillation criteria for the second-order nonlinear delay dynamic equations with damping on a time scale. Our results extend and improve some known theorems, but also unify the oscillation of the second-order nonlinear delay differential equation with damping and the second-order nonlinear delay difference equation with damping.  相似文献   
5.
In this paper, a class of second order nonlinear differential equations with perturbation is studied. By using the generalized Riccati transformation, the integral averaging technique and the method of classification, new oscillation criteria are obtained for all solutions of the equations, which generalize and improve some known results.  相似文献   
6.
汤文超  李文海  郑博  黄权欣 《应用声学》2014,22(8):2366-2368
针对传统层次分析(APH)方法在进行测试性分配时没有考虑人判断的模糊性,以及在构造判断矩阵时需要进行一致性检验这两个问题,建立了测试性分配层次结构模型,采用可拓层次分析法对测试性指标进行分配,将符合一致性要求的判断矩阵权重向量的方法有机地融合到可拓层次分析法中;最后结合实例对本文进行应用研究,求得了合适的分配指标,应用结果验证了此方法的可行性。  相似文献   
7.
邓露  许爱强  席靓  黄权欣 《应用声学》2014,22(8):2508-2511
装备在研制阶段通常缺乏有效的试验和使用数据,其测试性水平往往难以评估,针对上述问题,提出基于多源信息加权融合的研制阶段测试性评估方法;方法综合考虑了装备研制阶段可利用的仿真信息、专家经验信息以及类似装备的历史信息,构建了以3类信息为基础的装备测试性指标值密度分布函数,同时依据可信度原则确定了3类信息的融合权重;在此基础上,利用证据折扣组合方法评估装备当前的测试性水平;最后,通过案例应用证明了该方法的有效性。  相似文献   
8.
The pH effects on the photochemical reaction of amino acids and related dipeptides with 4-nitroquinoline 1-oxide (4NQO) as a photosensitizer have been investigated by laser flash photolysis. The obtained kinetic parameters show that the electron transfer from Tryptophan (Trp), Tyrosine (Tyr) as well as dipeptides containing Trp and/or Tyr residue to triplet 4NQO (T4NQO) are efficient, but inefficient from methionine (Met) and dipeptides containing neither Trp nor Tyr. The result was supported by the calculated values of the free energy change from measured oxidation potentials for the electron transfer. It was demonstrated that Trp and Tyr residues are initial reaction sites with T4NQO, while Tyr/O? radical may be final species for Trp-Tyr dipeptide. In acidic aqueous solutions, the self-quenching rate constants of T4NQO and the rate constants of electron transfer from amino acids to T4NQO decrease with decreasing pH. In alkaline solutions, amino acids are easily oxidized by 4NQO under irradiation of laser pulse, and no transient absorption signal was observed.  相似文献   
9.
利用Ar/CF4、Ar/CF2Cl2或Ar/CF3COOH混合气体的直流脉冲放电产生CF自由基,观测了260~360nm范围内转动分辨的CF自由基双光子共振增强多光子电离谱。分析表明,该段光 谱对应于CF自由基3pπD2Πr(ν'=2~6,r=3/2,1/2)←←X2Πr(ν"=0,r=3/2,1/2)的共振激发。对观测的振动带进行了转动分析,并获得了3p里德堡态的转动常数和自旋-轨道分裂值。  相似文献   
10.
Zhang  Guoping  Zhu  Quanxin 《Nonlinear dynamics》2021,105(1):387-401
Nonlinear Dynamics - For nonlinear Itô-type stochastic systems, the problem of event-triggered optimal control (ETOC) is studied in this paper, and the adaptive dynamic programming (ADP)...  相似文献   
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