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61.
《Wave Motion》2018
The breather solutions of the Maxwell–Bloch equations in a two-level resonant system associated with the self-induced transparency phenomenon are constructed by the Darboux transformation. After constructing the formulas of the second-order breather solutions, the double degeneration and hybrid solutions are studied by the analytical form as well as figures. Our results might be helpful in such application or prevention of the rogue waves from breather solution interactions and degeneration in the nonlinear optical systems associated with the Maxwell–Bloch equations. 相似文献
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This paper is concerned with a class of systems of delay differential equations which are defined on the nonnegative function space. Under proper conditions, we employ a novel proof to establish several criteria of the global stability of positive equilibrium. Moreover, we give two examples to illustrate our main results. 相似文献
65.
Hong Gao 《Applied mathematics and computation》2009,211(1):148-154
In this paper, we use the coincidence degree theory to establish new results on the existence and uniqueness of T-periodic solutions for a kind of forced Rayleigh equation of the form
x″+f(x′(t))+g(t,x(t))=e(t). 相似文献
66.
Haidong Liu 《Journal of Mathematical Analysis and Applications》2009,354(2):451-855
In this paper, we study a class of semilinear elliptic equations with Hardy potential and critical Sobolev exponent. By means of the Ekeland variational principle and Mountain Pass theorem, multiple positive solutions are obtained. 相似文献
67.
This paper applies the exp-function method, which was originally proposed to find new exact travelling wave solutions of nonlinear evolution equations, to the Riccati equation, and some exact solutions of this equation are obtained. Based on the Riccati equation and its exact solutions, we find new and more generalvariable separation solutions with two arbitrary functions of (1+1)-dimensional coupled integrable dispersionless system. As some special examples, some new solutions can degenerate into variable separation solutions reported in open literatures. By choosing suitably two independent variables p(x) and q(t) inour solutions, the annihilation phenomena of the flat-basin soliton, arch-basin soliton, and flat-top soliton are discussed. 相似文献
68.
以3,6-二溴-2,7-二羟基萘为起始原料,经与2-溴-N-苯基乙酰胺醚化,再用硼氢化钠和三氟化硼乙醚还原得基于萘基块新型的开链冠醚,两步总收率为96%.利用单晶X衍射研究其结构,晶体为三斜晶系,P-1空间群,a=9.588(3),b=10.898(3),c=13.060(4),α=103.190(4)°,β=93.953(4)°,γ=115.622(5)°,V=1176.0(6)3,Z=2,Dc=1.571 g/cm3,λ=0.71075 nm,μ(Mo Kα)=3.472 mm-1,Mr=353.22,F(000)=560.在晶体结构中,分子中的一个N—H基团与另外一分子形成双分叉氢键N—H…Br和N—H…O,进而组装成二聚体.这些中心对称的二聚体进一步通过C—H…π相互作用叠加成二维层状结构平行于(110)面. 相似文献
69.
Geometry optimization and subsequent harmonic vibration calculations of prior synthesized (E)-3-(4-fluorophenyl)-N-[4-(phenyl-amino) quinazoline-7-yl] acrylamide were carried out by DFT/B3LYP method with both 6-31G and 6-311G basis sets.The Infrared (IR) spectrum of the title compound was recorded in the field of 400-4000 cm 1 and then assigned.The correlation analyses between the scaled theoretical vibration frequencies and the experimental ones indicate that there exist good linearity relationships since the correlation coefficients R 2 are larger than 0.999.The intramolecular interactions existed in the title molecule were confirmed by the Atoms in molecules (AIM) method,and their influences on the absorption frequency were also investigated. 相似文献
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