Nanoindentation experiments were conducted under loading rates of 500–6000μN/s and applied peak loads of 4000-12000μN to measure the creep behavior of DD407 Ni-base single crystal superalloy at room temperature.Exp...Nanoindentation experiments were conducted under loading rates of 500–6000μN/s and applied peak loads of 4000-12000μN to measure the creep behavior of DD407 Ni-base single crystal superalloy at room temperature.Experimental results demonstrated that DD407 Ni-base single crystal superalloy had a good creep resistance,but its creep properties were sensitive to the loading rate and peak load.The fitting creep parameters significantly increased with increasing loading rate and peak load based on the Findley’s model,and the corresponding creep mechanism was governed by dislocation based on the calculation of creep stress exponent.During nanoindentation creep tests,it was found that the hardness and reduced modulus decreased with increasing the loading rate and peak load,and through a dimensionless analysis,it was also noted that the effect of the dimensionless loading rate was stronger than that of dimensionless peak load on the creep properties.展开更多
The paper deals with the methods of formation pressure evaluation for a single well by using the very common accepted parameters, such as drilling exponent , and flowline temperature , etc. which is part of compiling ...The paper deals with the methods of formation pressure evaluation for a single well by using the very common accepted parameters, such as drilling exponent , and flowline temperature , etc. which is part of compiling the end well report.展开更多
We study the following Schr?dinger equation with variable exponent−Δu+u=u^(p+∈a)(x),u>0 in R^(N),where∈>0,1<p<N+2/N−2,a(x)∈C^(1)(R^(N))∩L^(∞)(R^(N)),N≥3.Under certain assumptions on a vector field r...We study the following Schr?dinger equation with variable exponent−Δu+u=u^(p+∈a)(x),u>0 in R^(N),where∈>0,1<p<N+2/N−2,a(x)∈C^(1)(R^(N))∩L^(∞)(R^(N)),N≥3.Under certain assumptions on a vector field related to a(x),we use the Lyapunov–Schmidt reduction to show the existence of single peak solutions to the above problem.We also obtain local uniqueness and exact multiplicity results for this problem by the Pohozaev type identity.展开更多
In this paper, the existence of chaotic behavior in the single-well Duffing Oscillator was examined under parametric excitations using Melnikov method and Lyapunov exponents. The minimum and maximum values were obtain...In this paper, the existence of chaotic behavior in the single-well Duffing Oscillator was examined under parametric excitations using Melnikov method and Lyapunov exponents. The minimum and maximum values were obtained and the dynamical behaviors showed the intersections of manifold which was illustrated using the MATCAD software. This extends some results in the literature. Simulation results indicate that the single-well oscillator is sensitive to sinusoidal signals in high frequency cases and with high damping factor, the amplitude of the oscillator was reduced.展开更多
基金financial supports from the National Natural Science Foundation of China(Nos.11772236,11472195)。
文摘Nanoindentation experiments were conducted under loading rates of 500–6000μN/s and applied peak loads of 4000-12000μN to measure the creep behavior of DD407 Ni-base single crystal superalloy at room temperature.Experimental results demonstrated that DD407 Ni-base single crystal superalloy had a good creep resistance,but its creep properties were sensitive to the loading rate and peak load.The fitting creep parameters significantly increased with increasing loading rate and peak load based on the Findley’s model,and the corresponding creep mechanism was governed by dislocation based on the calculation of creep stress exponent.During nanoindentation creep tests,it was found that the hardness and reduced modulus decreased with increasing the loading rate and peak load,and through a dimensionless analysis,it was also noted that the effect of the dimensionless loading rate was stronger than that of dimensionless peak load on the creep properties.
文摘The paper deals with the methods of formation pressure evaluation for a single well by using the very common accepted parameters, such as drilling exponent , and flowline temperature , etc. which is part of compiling the end well report.
基金National Natural Science Foundation of China(Grant Nos.11971147 and12371111)The second author is partially supported by National Natural Science Foundation of China(Grant No.11831009)+1 种基金the Fundamental Research Funds for the Central Universities(Grant Nos.KJ02072020-0319,CCNU22LJ002)The third author is supported by National Natural Science Foundation of China(Grant No.12201232)。
文摘We study the following Schr?dinger equation with variable exponent−Δu+u=u^(p+∈a)(x),u>0 in R^(N),where∈>0,1<p<N+2/N−2,a(x)∈C^(1)(R^(N))∩L^(∞)(R^(N)),N≥3.Under certain assumptions on a vector field related to a(x),we use the Lyapunov–Schmidt reduction to show the existence of single peak solutions to the above problem.We also obtain local uniqueness and exact multiplicity results for this problem by the Pohozaev type identity.
文摘In this paper, the existence of chaotic behavior in the single-well Duffing Oscillator was examined under parametric excitations using Melnikov method and Lyapunov exponents. The minimum and maximum values were obtained and the dynamical behaviors showed the intersections of manifold which was illustrated using the MATCAD software. This extends some results in the literature. Simulation results indicate that the single-well oscillator is sensitive to sinusoidal signals in high frequency cases and with high damping factor, the amplitude of the oscillator was reduced.