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The Thomson scattering spectra by an electron moving in the laser-magnetic resonance acceleration regime are computed numerically and analytically. The dependence of fundamental frequency on the laser intensity and magnetic resonance parameter is examined carefully. By calculating the emission of a single electron in a circularly polarized plane-wave laser field and constant external magnetic field, the scale invariance of the radiation spectra is evident in terms of harmonic orders. The scaling law of backscattered spectra are exhibited remarkably for the laser intensity as well for the initial axial momentum of the electron when the cyclotron frequency of the electron approaches the laser frequency. The results indicate that the magnetic resonance parameter plays an important role on the strength of emission. And the rich features of scattering spectra found may be applicable to the radiation source tunability.

By implementing the bremsstrahlung with Monte Carlo algorithm into the particle-in-cell code, the bremsstrahlung and nonlinear Compton scattering can be studied simultaneously in comparison way in the laser plasma interactions. The simulations are performed for the laser of different intensities interacting with either low-Z or high-Z target. The relative strength of the two photon emission from bremsstrahlung and nonlinear Compton scattering are compared. The result shows that when an ultrastrong intensity laser interacting with a thin and relative high Z target the nonlinear Compton scattering is dominant, however, when the laser intensity I < 10 22 W/cm 2 , the photon emission contributed by bremsstrahlung is comparable to that from nonlinear Compton scattering. In this case the usual ignorable of bremsstrahlung need to be reconsidered.

The mechanism of the cross-linking reaction between hydrolyzed polyacrylamide (HPAM) and chromium acetate in formation water was systematically studied by viscometry, ultraviolet-visual absorption spectrometry, and core flow experiments. The results show that the process and outcome of the cross-linking reaction between HPAM and chromium acetate is significantly affected by salinity. In formation water, chromium acetate cannot cross-link HPAM when the salinity is too low. With an increase of salinity, the cross-linking reaction occurs, and the degree of the reaction increases to a balance point. When the cross-linking reaction occurs, two different types of the reaction appear under different salinity. The intramolecular crosslinking reaction is the first to happen, whether under high salinity or under low salinity. In this stage, the cross-linking reaction is a first-order reaction and plays a greater role in the whole process of the reaction due to its higher reaction rate and higher reaction degree. Next, the intramolecular cross-linking continues to occur if the formation water is in the low salinity range, but the intermolecular cross-linking reaction occurs if the formation water is in the high salinity range. In this stage, the cross-linking reaction is a multistage reaction. Meanwhile, the experiments quantify a matching relationship between cations in the formation water and the profile control and oil displacement agent. The experimental results in this paper can provide theoretical guidance for the practical application of profile control and oil displacement using HPAM/Ac 3 Cr.

Thomson backscattering in combined fields with a general elliptical polarization of laser field and an applied constant magnetic field is studied. The monotonous and non-monotonous dependence of emission spectra on the ellipticity and the initial phase of laser field are found. We have also revealed the scaling law of the radiation spectra about the initial axial momentum in the general elliptic polarized case that is similar to the circularly polarized one. However, the scaling law about the laser intensity exists conditionally and the scale invariance about the magnetic resonance parameter exists, too. Another interesting feature is the feasibility to obtain the THz radiation by this scheme.