Electron fluxes in the outer radiation belt are essentially governed by the dynamics of trapped particle motion in the inner magnetosphere, wherein the energetic particles execute complex periodic motions. Each motion is associated with one adiabatic invariant, namely, gyromotion around the magnetic field line, which is described as the first adiabatic invariant, bounce motion along the magnetic field line being identified as the second adiabatic invariant, and drift motion around the Earth as the third adiabatic invariant (Northrop & Teller, 1960; Roederer, 1970). Early spacecraft data revealed that phase space densities across the belts can vary significantly with time (see Roederer 1968), in which the violation of one or more adiabatic invariants can be required. This violation can occur due to the presence of several electrodynamic and magnetohydrodynamic processes in the magnetosphere, causing variations in the outer radiation belt electron flux, such as dropouts (e.g.,

In the conventional preconditioning followed by refiner chemical treatment, alkaline peroxide mechanical pulping (P-RC APMP) process, sodium hydroxide (NaOH) is used as the alkali source. In this study, magnesium oxide (MgO) was used to partially substitute for NaOH as the alkali source (substitution ratio of up to 50%) in the second-stage impregnation of the triploid poplar P-RC APMP process. The changes in pH values of the residual bleaching liquor, yields, and chemical components of the treated wood chips in the second-stage impregnation and also the physical properties of the resultant P-RC APMP pulps with and without MgO substitution were investigated to explore the potential advantages of the process. The results showed that the partial MgO substitution for NaOH resulted in a lower pH of residual bleaching liquor and a higher treated wood chips yield than those of the NaOH-based process. In addition, the dissolution of benzene alcohol extractives, lignin, pentosans, and carbohydrates were all decreased. The resultantly yielded P-RC APMP pulp has a higher bulk, opacity, and light-scattering coefficient, but lower strength properties and a slightly lower brightness.