2010.3--2012.3  南开大学陈省身数学研究所  博士后

2009.7-2012.9   吉林大学数学学院, 讲师

主要应用变分与拓扑方法研究非线性（非局部）薛定谔方程（组）解的存在性、多重性，解的集中等。

近期感兴趣的领域：

1. 图上的变分方法及其应用（度量图、离散图)。

2.各种非线性薛定谔方程（组）的正规化解问题。

主要工作如下：

1. J. Borthwick, X. J. Chang, L. Jeanjean and N. Soave,  Bounded Palais-Smale sequences with Morse type information for some constrained functionals, Trans. Amer. Math. Soc., 377(2024), no.6, 4481–4517.

2. X. J. Chang, L. Jeanjean and N. Soave, Normalized solutions of $L^2$-supercritical NLS equations on compact metric graphs, Annales de l Institut Henri Poincare (C) Non Linear Analysis, 41(2024),no.4, 933–959.

3. Qun Wang, X. J. Chang, Normalized solutions of L2-supercritical Kirchhoff equations in bounded domains.  J. Geom. Anal. DOI: 10.1007/s12220-024-01793-5.

4. Qian Gao, Qun Wang, X. J. Chang, Normalized ground state solutions of Schrödinger-KdV
system in R^3,  Z. Angew. Math. Phys. DOI: 10.1007/s00033-024-02330-8.

5. M. T. Liu and X. J. Chang, Normalized ground state solutions for nonlinear Schrodinger equations with general Sobolev critical nonlinearities, Discrete Contin. Dyn. Syst. Ser. S. Online, DOI: 10. 3934/dcdss.2024035.

6. X. J. Chang, Y. Sato and Chengxiang, Zhang, Multi-peak solutions of a class of fractional p-Laplacian equations,J. Geom. Anal. 34(2024), no. 1,  Paper No. 29, 36 pp.

7. J. Borthwick, X. J. Chang, L. Jeanjean and N. Soave,  Normalized solutions of $L^2$-supercritical NLS equations on noncompact metric graphs with localized nonlinearities,  Nonlinearity. 36(2023) 3776-3795.

8. X. J. Chang, R. Wang and D. K. Yan, Ground states for logarithmic Schrödinger equations on locally finite graphs.  J. Geom. Anal. 33 (2023), no. 7, Paper No. 211, 26 pp.
9. X. J. Chang,  M. T. Liu and D. K. Yan, Normalized ground state solutions of nonlinear Schrödinger equations involving exponential critical growth.  J. Geom. Anal. 33 (2023), no. 3, Paper No. 83, 20 pp.

10. X. J. Chang and  Y. Sato, Localized solutions of nonlinear Schrödinger systems with critical frequency for infinite attractive case. NoDEA Nonlinear Differential Equations Appl. 26 (2019), no. 5, Paper No. 31, 31 pp.

11. X. J. Chang, Z. H. Nie and Z.-Q. Wang, Sign-changing solutions of fractional p-Laplacian problems.
Adv. Nonlinear Stud. 19 (2019), no. 1, 29–53.

12.X. J. Chang, T. C. Ouyang and D. K. Yan, Linear stability of the criss-cross orbit in the equal-mass three-body problem. Discrete Contin. Dyn. Syst. 36 (2016), no. 11, 5971–5991.

13. X. J. Chang and Y. Li, Rotating periodic solutions of second order dissipative dynamical systems. Discrete Contin. Dyn. Syst. 36 (2016), no. 2, 643–652.

14. X. J. Chang, Ground states of some fractional Schrödinger equations on RN. Proc. Edinb. Math. Soc. (2) 58 (2015), no. 2, 305–32.

15. X. J. Chang and Z.-Q. Wang, Nodal and multiple solutions of nonlinear problems involving the fractional Laplacian. J. Differential Equations 256 (2014), no. 8, 2965–2992.

16. X. J. Chang and Z.-Q. Wang, Ground state of scalar field equations involving a fractional Laplacian with general nonlinearity. Nonlinearity 26 (2013), no. 2, 479–494.

17. X. J. Chang, Ground state solutions of asymptotically linear fractional Schrödinger equations. J. Math. Phys. 54 (2013), no. 6, 061504, 10 pp.

18.X. J. Chang, Multiplicity of solutions for semilinear elliptic problems with combined nonlinearities. Commun. Contemp. Math. 13 (2011), no. 3, 389–405.

19.X. J. Chang and Y. Li, Existence and multiplicity of nontrivial solutions for semilinear elliptic Dirichlet problems across resonance. Topol. Methods Nonlinear Anal. 36 (2010), no. 2, 285–310.

20. X. J. Chang, Y. Li and S. G. Ji, Nonresonance conditions on the potential with respect to the Fučík spectrum for semilinear Dirichlet problems. Z. Angew. Math. Phys. 61 (2010), no. 5, 823–833.

21. X. J. Chang and Q. D. Huang, Two-point boundary value problems for Duffing equations across resonance. J. Optim. Theory Appl. 140 (2009), no. 3, 419–430.