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In this article, we consider a (3 + 1)-dimensional Sharma–Tasso–Olver-like (STOL) model describing dynamical propagation of nonlinear dispersive waves in inhomogeneous media. Applying Hirota's bilinear technique and a trial function, we explore nonlinear dynamical properties of basic solutions to the STOL model. We find that the fission fusion pattern occurs in the collision between the lump and kink waves, the collision between the lump and periodic waves, and the collision among the lump, kink and periodic waves, which is a novel fascinating collision pattern. We also observe that a large value of the coefficient in the periodic function produces a hybrid lump wave by fission in the collision solution. To better understand the dynamic properties of the obtained collision solutions, we plot a number of 3D and contour diagrams by choosing suitable parametric values with the aid of the computational software Maple 18.  相似文献   
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林元华 《高分子科学》2015,33(2):339-348
The influence of poly(methylmethacrylate-co-N-vinyl-2-pyrrolidone), P(MMA-co-VP), on corrosion of carbon steels(J55, N80, P110 SS and C110 steels) in 3.5 wt% NaCl solution saturated with CO2 was evaluated using static high pressure and high temperature(HPHT) autoclave. The surface was further evaluated by X-ray diffraction(XRD), scanning electron microscopy(SEM) and contact angle measurements. Quantum chemical calculations have been used to evaluate the structural, electronic and reactivity parameters of the inhibitor on the steels surface. SEM, XRD and contact angle measurement studies reveal that the surface of metals are quite unaffected after use of inhibitor in 3.5% NaCl solution saturated with CO2.  相似文献   
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McAnally  Morgan  Ma  Wen-Xiu 《Nonlinear dynamics》2020,102(4):2767-2782
Nonlinear Dynamics - Darboux and Bäcklund transformations on integrable couplings are formulated and generalized. The generalization of the theory pertains to spectral problems where the...  相似文献   
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This paper studies the Biswas–Milovic equation that is a generalized version of the familiar nonlinear Schrodinger's equation describing the propagation of solitons through optical fibers for trans-continental and trans-oceanic distances with Kerr law nonlinearity by the aid of the first integral method. The dark 1-soliton solution is retrieved by the aid of this method and a couple of other singular periodic solutions are also obtained.  相似文献   
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The effectiveness of the neutralization process on heavy metals precipitated in sludge has been evaluated using instrumental neutron activation analysis (INAA) facilities at the South African Nuclear Energy Corporation (Necsa). The elemental concentrations of Th, Fe, Ag, Co, Cr, As, Au and K were reduced after the neutralization process with the exception of Mn and Sn which appeared to be enhanced by the neutralization process. Even though the neutralization process was targeted at the basic ferric arsenate compound, it was found to be effective in reducing other elemental concentrations. The variations in the geochemical compositions of the sulphidic ores during treatment at various stages also showed that physical processing stages do not significantly alter the elemental concentrations in the feed materials, however, the chemically active processing stages do. Also, the enhancement of the elements at the chemical stages depends on total quality control, where the application was not very repeatable the pattern of variation of elements at some stages was found to be irregular irrespective of the ore grade. The elements; Sn, Fe, Th, K, Au, Ag, As, Cr, and Co were enhanced in almost all the chemically active stages. Au was much more enhanced during flotation and bio-oxidation processes. Correlation analysis performed to determine the distribution patterns show that Fe, As, Ag and Co are geochemically associated and might be enriched simultaneously.  相似文献   
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