Localized characteristics of lump and interaction solutions to two extended Jimbo–Miwa equations

We focus on the localized characteristics of lump and interaction solutions to two extended Jimbo–Miwa equations.Based on the Hirota bilinear method and the test function method,we construct the exact solutions to the extended equations including lump solutions,lump–kink solutions,and two other types of interaction solutions,by solving the underdetermined nonlinear system of algebraic equations for associated parameters.Finally,analysis and graphical simulation are presented to show the dynamical characteristics of our solutions and the interaction behaviors are revealed.

Study on the appropriate dose of dexmedetomidine leading analgesia combined with transverse abdominal plane block for postoperative analgesia in colon cancer

Objective:To explore the suitable dosage of dexmedetomidine preemptive analgesia combined with transverse abdominal muscle block for postoperative analgesia of colon cancer.Methods:From March 2018 to October 2019,120 patients undergoing laparoscopic radical resection of colon cancer in our hospital were randomly divided into control group(group C,without dexmedetomidine),low-dose group(group L,0.5μg/kg),medium-dose group(group M,1μg/kg)and high-dose group(group M,0.5μg/kg)The Mean arterial pressure,MAP),Heart rate,HR)and visual analog scale(vas)pain were compared at 2 h(T0),4 h(T1),8 h(T2),12 h(T3),24 h(T4)and 48 h(T5)after operation The pain sensitive area of mechanical stimulation was measured at T4,T5 and 72 h(T6)after operation.The adverse reactions of patients after operation were compared.Results:Compared with C group,MAP and HR of L,M and H groups decreased in different degrees at each time point.MAP and HR of m and h groups were lower than those of l group at different time points(P<0.05).The VAS score and pain sensitive area of T4-T6 in l,m and h groups were significantly lower than those in c group(P<0.05),but there was no significant difference in Ramsay score among groups(p>0.05).The vas score and pain sensitive area of m and h groups were lower than those of l group(P<0.05).Incidence of postoperative adverse reactions in l,m and h groups was lower than that in c group(P<0.05).Conclusion:Dexmedetomidine at doses of 1μg/kg and 1.5μg/kg has a good analgesic effect without increasing the incidence of adverse reactions.It is recommended that 1μg/kg Dexmedetomidine be used as an auxiliary drug dose of ropivacaine during TAP block.At the same time,it is necessary to strengthen monitoring to avoid adverse reactions such as hypotension and bradycardia.

Rogue wave solutions and rogue-breather solutions to the focusing nonlinear Schr?dinger equation

Based on the long wave limit method,the general form of the second-order and third-order rogue wave solutions to the focusing nonlinear Schr?dinger equation are given by introducing some arbitrary parameters.The interaction solutions between the first-order rogue wave and one-breather wave are constructed by taking a long wave limit on the two-breather solutions.By applying the same method to the three-breather solutions,two types of interaction solutions are obtained,namely the first-order rogue wave and two breather waves,the second-order rogue wave and one-breather wave,respectively.The influence of the parameters related to the phase on the interaction phenomena is graphically demonstrated.Collisions occur among the rogue waves and breather waves.After the collisions,the shape of them remains unchanged.The abundant interaction phenomena in this paper will contribute to a better understanding of the propagation and control of nonlinear waves.

Dynamic behaviors of the lump solutions and mixed solutions to a(2+1)-dimensional nonlinear model

In this paper,we propose a combined form of the bilinear Kadomtsev-Petviashvili equation and the bilinear extended(2+1)-dimensional shallow water wave equation,which is linked with a novel(2+1)-dimensional nonlinear model.This model might be applied to describe the evolution of nonlinear waves in the ocean.Under the effect of a novel combination of nonlinearity and dispersion terms,two cases of lump solutions to the(2+1)-dimensional nonlinear model are derived by searching for the quadratic function solutions to the bilinear form.Moreover,the one-lump-multi-stripe solutions are constructed by the test function combining quadratic functions and multiple exponential functions.The one-lump-multi-soliton solutions are derived by the test function combining quadratic functions and multiple hyperbolic cosine functions.Dynamic behaviors of the lump solutions and mixed solutions are analyzed via numerical simulation.The result is of importance to provide efficient expressions to model nonlinear waves and explain some interaction mechanism of nonlinear waves in physics.

The influence of adding niobium and vanadium on hydrogen diffusion in 22MnB5 hot stamping steel

Adding alloying elements is always considered as an effective method to enhance the resistance against hydrogen embrittlement in steels.Nb and V were added into 22MnB5 hot stamping steel,and then their influences on hydrogen permeation of 22MnB5 steel suffering from corrosion in 3.5%NaCl aqueous solution were investigated.The results showed that the addition of Nb/V could reduce the hydrogen permeation content due to solution corrosion.Electrochemical techniques including electrochemical impedance spectroscopy and overpotential stepping hydrogen permeation test con-firmed that compared to the original 22MnB5 steel,22MnB5-NbN steel owned a higher corrosion resistance and a higher hydrogen diffusion resistance.Furthermore,it was confirmed that Nb-V-alloyed 22MnB5 steel showed higher resistance against hydrogen embrittlement than the Nb-V-free counterpart,which should be related to the presentence of nanoscaled Nb/V-containing precipitates as the irreversible trapping sites for hydrogen detected by thermal desorption spectroscopy.Finally,the lattice diffusion coefficient of hydrogen DL was determined in steels with and without Nb and V.