Toroidal computations are performed using the MARS-F code [Liu Y Q et al 2000 Phys.Plasmas 7 3681], in order to understand correlations between the plasma response and the observed mitigation of the edge localized modes (ELM) using resonant magnetic perturbation fields in ASDEX Upgrade. In particular, systematic numerical scans of the edge safety factor reveal that the amplitude of the resonant poloidal harmonic of the response radial magnetic field near the plasma edge, as well as the plasma radial displacement near the X-point, can serve as good indicators for predicting the optimal toroidal phasing between the upper and lower rows of coils in ASDEX Upgrade. The optimal coil phasing scales roughly linearly with the edge safety factor 95 q , for various choices of the toroidal mode number n=1-4 of the coil configuration. The optimal coil phasing is also predicted to vary with the upper triangularity of the plasma shape in ASDEX Upgrade. Furthermore, multiple resonance effects of the plasma response, with continuously varying 95 q , are computationally observed and investigated.

Volatile organic compounds (VOCs) such as benzene (C 6 H 6 ), methylbenzene (C 6 H 5 CH 3 ), dichloromethane (CH 2 Cl 2 ) and methyl ethyl ketone (CH 3 COCH 2 CH 3 ), are exhausted into the atmosphere from a variety of industrial processes [1]. The removals of these VOCs are required because they are responsible for many environmental problems and diseases such as ozone depletion, photochemical smog, heart disease, asthma and even cancer [1][2][3][4]. There exist a lot of traditional techniques for VOCs degradation, including adsorption, incineration and condensation [5][6][7][8]. These methods have

Plasma response to 3D resonant magnetic perturbations (RMPs), applied for the purpose of controlling type-I edge localized modes (ELMs) in ITER with the baseline ELM control coils, is computed using a toroidal, resistive, full magneto-hydrodynamic model. Considered are five representative ITER plasmas, designed for different phases of the ITER exploration. The plasma response, measured by the plasma boundary corrugation, is found to be similar for the two DT scenarios at full plasma current (15 MA) and full toroidal field (5.3 T) but different fusion gain factors (Q  =  5 versus Q  =  10), indicating similar ELM control performance with the same RMP coil current configuration. The other plasma scenarios, with proportionally scaled down plasma current and toroidal field, can have different plasma boundary corrugation. The key plasma parameter affecting the response is the plasma toroidal flow near the pedestal region, which significantly varies depending on the transport model assumption for the toroidal momentum. Lower pedestal flow leads to a stronger edge peeling response from the plasma and thus probably a better ELM control. The optimal coil configuration for controlling type-I ELMs is similar for all four ITER plasmas with similar safety factor but different current levels, but is significantly different for the case at half plasma current (7.5 MA) and full field (5.3 T). On the other hand, for the purpose of controlling the radial profile of the plasma toroidal rotation in ITER using 3D fields, the relative amplitude of the toroidal torque density, between the plasma core and edge region, is optimized. Generally, a strong coupling between the core and edge torques is observed, largely due to the middle row ELM control coils. The best decoupling scheme of the core-edge torque distribution thus de-emphasizes the role of the middle row coils. Optimal coil current configurations are found for the ITER 15 MA/5.3 T Q  =  10 plasma, that synergistically maximize the plasma edge-peeling response (indication for good ELM control) and the toroidal torque near the plasma edge (good for RMP field penetration through pedestal).

A systematic numerical study is carried out, computing the resistive plasma response to the resonant magnetic perturbation (RMP) fields for ITER plasmas, utilizing the toroidal code MARS-F (Liu et al 2000 Phys. Plasmas 7 3681). A number of factors are taken into account, including the variation of the plasma scenarios (from 15 MA Q=10 inductive scenario to the 9 MA Q=5 steady state scenario), the variation of the toroidal spectrum of the applied fields (n=1, 2, 3, 4, with n being the toroidal mode number), the amplitude and phase variation of the currents in three rows of the RMP coils as designed for ITER, and finally a special case of mixed toroidal spectrum between the n=3 and n=4 RMP fields. Two-dimensional parameter scans, for the edge safety factor and the coil phasing between the upper and lower rows of coils, yield 'optimal' curves that maximize a set of figures of merit, that are defined in this work to measure the plasma response. Other two-dimensional scans of the relative coil current phasing among three rows of coils, at fixed coil currents amplitude, reveal a single optimum for each coil configuration with a given n number, for the 15 MA ITER inductive plasma. On the other hand, scanning of the coil current amplitude, at fixed coil phasing, shows either synergy or cancellation effect, for the field contributions between the off-middle rows and the middle row of the RMP coils. Finally, the mixed toroidal spectrum, by combining the n=3 and the n=4 RMP field, results in a substantial local reduction of the amplitude of the plasma surface displacement.

A novel strategy for degradation of high gaseous hourly space velocity (GHSV) benzene, toluene, xylene (BTX) by double dielectric barrier discharge (DDBD) coupled with Mn3O4/ activated carbon fibers (ACF) catalysts was proposed in this work. A series of Mn3O4/ACF catalysts were synthesized by hydrothermal method and characterized. The results showed that all the prepared catalysts could improve the degradation of BTX in DDBD system and inhibit the production of ozone. Among the catalysts with different Mn loading, the 5.6%Mn3O4/ACF, with the highest Mn(+3) content (43.2%) and the highest absorbed oxygen content (38.5%), presented the best catalytic performance. In 5.6%Mn3O4/ACF+DDBD system, the degradation efficiency of benzene, toluene and xylene could reach 49.9%, 79.7% and 97.1% respectively with SIE of 400 J L-1. The carbon balance and CO2 selectivity, meanwhile, were 83.3% and 51.1%, respectively. It seemed that Mn(+3) and absorbed oxygen content could be a reference for the catalytic performance of Mn3O4/ACF catalysts. The higher the Mn (Ⅲ) and absorbed oxygen, the better the catalytic performance of the Mn3O4/ACF catalysts. The organic by-products were identified by chromatography-mass spectrometry (GC-MS), and a possible reaction mechanism of BTX in DDBD reactor and catalyst surface was proposed based on the composition of organic by-products.