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排序方式: 共有291条查询结果,搜索用时 15 毫秒
111.
This paper obtains the solutions of the Kuramoto-Sivashinsky equation. The G′/G method is used to carry out the integration of this equation. Subsequently, its special case, will be integrated and topological 1-soliton solution will be obtained by the soliton ansatz method. The restrictions on the parameters and exponents are also identified. 相似文献
112.
Photoinduced electron transfer between coumarin dyes and N,N-dimethylaniline has been investigated by using steady state and picosecond time resolved fluorescence spectroscopy in sodium dodecyl sulphate (SDS) micelles and PVP-polyvinyl pyrrolidone (SDS) polymer-surfactant aggregates. A slower rate of electron transfer is observed in PVP-SDS aggregates than in polymer-free SDS micelles. A Marcus type inversion is observed in the correlation of free energy change in comparison with the electron transfer rate. The careful investigation reveals that C-151 deviates from the normal Marcus inverted region compared to its analogs C-152 and C-481 due to slower rotational relaxation and smaller translational diffusion coefficient. 相似文献
113.
Anjan Biswas Yakup Yıldırım Emrullah Yaşar Qin Zhou Ali Saleh Alshomrani Seithuti P. Moshokoa Milivoj Belic 《Optical and Quantum Electronics》2018,50(3):149
This paper reveals bright, dark and singular soliton solutions to the perturbed Gerdjikov–Ivanov equation by the aid of extended Kudryashov’s method. The nonlinear terms appear with full nonlinearity in order to give a generalized flavor to the model. As a byproduct of this scheme, plane waves and singular periodic solutions fall out and these solutions are listed as well. 相似文献
114.
The evolution of quasilinear optical pulses in multiple channels, with strong dispersion-management, is studied analytically. The nonlinear terms of the Gabitov-Turitsyn equations are analysed asymptotically. The total spectral intensity, for a lossless system, is found to be an invariant of propagation, while for a lossy system it is dependent on the relative position of the amplifier in the dispersion map. 相似文献
115.
Anjan Biswas 《Optical and Quantum Electronics》2005,37(4):359-369
The soliton perturbation theory is used to study and analyze the stochastic perturbation of optical solitons, due to Kerr law nonlinearity, in addition to deterministic perturbations of optical solitons that is governed by the nonlinear Schrödingers equation. The Langevin equations are derived and analyzed. The deterministic perturbations that are considered here are of both Hamiltonian as well as of non-Hamiltonian type. 相似文献
116.
Reactions of ((NacNac)Ni)2(mu-eta3-eta3-C6H5Me) (NacNac = HC(CMeNC6H3(i-Pr)2)2) with PH2Ph or PHPh2 proceeds in a facile manner to afford the Ni(I)-phosphine adducts (NacNac)Ni(PH2Ph) and (NacNac)Ni(PHPh2) , respectively. The related reactions of the Fe(I) complex (NacNac)Fe(eta2-CH2CPh2) with PH2Ph resulted in the formation of [(NacNac)Fe(mu2-PPh)]2. Alternatively was also obtained from the reaction of [(NacNac)Fe(mu-Cl)]2 with PHPh2 and Na/K. The Ni(II) di-phosphosphine bridged compound [((NacNac)Ni)2(mu4-(PPh)2)] was prepared via reaction of ((NacNac)Ni)2(mu-eta3-eta3-C6H5Me) with P5Ph5. Crystallographic data are reported for compounds . 相似文献
117.
The dynamics of solvent and rotational relaxation of Coumarin 480 and Coumarin 490 in glycerol containing bis-2-ethyl hexyl sulfosuccinate sodium salt (AOT) reverse micelles have been investigated with steady-state and time-resolved fluorescence spectroscopy. We observed slower solvent relaxation of glycerol confined in the nanocavity of AOT reverse micelles compared to that in pure glycerol. However, the slowing down in the solvation time on going from neat glycerol to glycerol confined reverse micelles is not comparable to that on going from pure water or acetonitrile to water or acetonitrile confined AOT reverse micellar aggregates. While solvent relaxation times were found to decrease with increasing glycerol content in the reverse micellar pool, rotational relaxation times were found to increase with increase in glycerol content. 相似文献
118.
Busacca CA Lorenz JC Grinberg N Haddad N Lee H Li Z Liang M Reeves D Saha A Varsolona R Senanayake CH 《Organic letters》2008,10(2):341-344
Asymmetric hydrogenation of unsaturated urea esters with the BIPI Ligands has been examined. Optimization of the P-N ligand structure has led to the development of chiral rhodium catalysts capable of producing the targets with >99% ee. The critical phosphine borane SNAr reaction needed for ligand synthesis has been optimized to give the adducts in high yield at ambient temperature with no racemization. An extremely concise, economical, and scalable sequence to these important new ligands for catalysis of asymmetric hydrogenation has been developed. 相似文献
119.
Pali Maiti Totan Ghosh Anjan Banerjee Arpita Banerjee Santanu Bhattacharya Eringathodi Suresh Debasis Das 《Transition Metal Chemistry》2011,36(2):195-199
A dinuclear MnII complex, namely [Mn2L2(μ1,5-dca)2(dca)2]·H2O [L = N,N′-ethylenebis(2-benzoylpyridineimine), dca = dicyanamide], has been synthesized and structurally characterized in
order to study its catecholase-like activity. Single-crystal X-ray analysis revealed that the molecule possesses a center
of inversion at the midpoint of the line bisecting the adjacent metal centers of the dimers. The coordination number of each
MnII center is seven, and the coordination geometry is approximately distorted pentagonal bipyramid. The complex is an efficient
catalyst for the oxidation of 3,5-di-tert-butylcatechol to 3,5-di-tert-butylbenzoquinone under air in methanol solution but is inactive in acetonitrile solution. A kinetic study of the catalysis
was treated on the basis of the Michaelis–Menten model and reveals high turnover numbers (k
cat = 4.5 × 102 h−1) in methanol. 相似文献
120.
Maxwell's equations for a metallic and nonlinear Kerr interface waveguide at the nanoscale can be approximated to a (1+1) D Nonlinear Schrodinger type model equation (NLSE) with appropriate assumptions and approximations. Theoretically, without losses or perturbations spatial plasmon solitons profiles are easily produced. However, with losses, the amplitude or beam profile is no longer stationary and adiabatic parameters have to be considered to understand propagation. For this model, adiabatic parameters are calculated considering losses resulting in linear differential coupled integral equations with constant definite integral coefficients not dependent on the transverse and longitudinal coordinates. Furthermore, by considering another configuration, a waveguide that is an M–NL–M (metal–nonlinear Kerr–metal) that tapers, the tapering can balance the loss experienced at a non-tapered metal/nonlinear Kerr interface causing attenuation of the beam profile, so these spatial plasmon solitons can be produced. In this paper taking into consideration the (1+1)D NLSE model for a tapered waveguide, we derive a one soliton solution based on He's Semi-Inverse Variational Principle (HPV). 相似文献