In the previous work[1], we have presented a new kind of instability in the toroidal plasmas: magnetic curvature (MC)-driven one. The MC instability is characterized by possessing the finite growth rate when both η_i=L_n/L_Ti and η_e=L_n/L_Te are zero but ε_n=L_n/R is appropriately large. In addition, no matter what magnitudes the η_i and η_e are, the instability can be stabilized as long as the magnetic curvature is zero. In this paper, we study the interaction between the trapped electrons[2] and MC drift wave. It is found that, after the trapped electrons are included, there exist the ion and electron heat pinch driven by the modes with k_⊥² < η_e/2 and the particle pinch by the modes with k_⊥² > η_e/2. Especially in the position of K_//≈0, the significant particle pinch (if the mode with k_⊥²> η_e/2 is destabilized) and ion and electron heat pinch (if the mode with k_⊥² < η_e/2 is destabilized) are induced by the electron-wave resonance. Compared with the MC instability without the trapped electron effects, however, the electron-wave resonance destabilizes the modes with the short wavelength (k_⊥²>> η_e/2, i.e., kρ_i>>1)[3]. In the regime, they contribute the significant positive value to χ_i and χ_e (but the significant negative value to D_e). Finally, a nonlinear equation, describing the wave-wave couplings with the trapped electron effects, is given, which is retained for the future numerical research. If the wave-wave couplings make the energy of the short wavelength modes cascade toward the long wavelength modes and balance the turbulent transport competition between the short (k_⊥² < η_e/2) and long (k_⊥² > η_e/2) wavelength modes, the present electron-wave resonance-induced pinches in the position of K _//≈0 are possible candidates to explain the experimental facts that the transport barriers have been always observed at or near the rational surface.

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