at Austin in USA, was dismantled and shipped to China in 2004, and renamed as the Joint TEXT (J-TEXT) tokamak. The reconstruction work, which included reassembly of the machine and development of peripheral devices, was completed in spring of 2007. Consequently, the first plasma was obtained at the end of 2007. At present, a typical J-TEXT Ohmic discharge can produce a plasma with flattop current up to 220kA and lasting for 300ms, line averaged density above 2×10 19 m-3 , and an electron temperature about 800eV, with a toroidal magnetic field of 2.2T. A number of diagnostic devices used to facilitate the routine operation and experimental scenarios were developed on the J-TEXT tokamak. Hence, the measurements of the electrostatic fluctuations in the edge region and conditional analysis of the intermittent burst events near the last closed flux surface (LCFS) were undertaken. The observation and simple analysis of MHD activity and disruption events were also performed. The preliminary experimental results and the future research plan for the J-TEXT are described in detail.

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In this paper we report a statistical-mechanics-based continuum theory allowing tackling the simulation of electrochemical double layers under non-equilibrium conditions at electrolyte/electrode interfaces relevant to electrochemical cells for energy conversion and storage. The present theory is designed to capture the impact onto the overall electrode behavior of the electrolyte composition in terms of solvent, charged polymers and ions concentration, for a large diversity of cases, from diluted solutions to ionic liquids. From its continuum character, the theory is particularly useful for the simulation of interfacial electrochemical mechanisms within multiscale frameworks scaling up atomistic and molecular level properties onto overall performance cell models. Results obtained with our home-made MS LIBER-T simulation package are presented and discussed within the context of fuel cells and lithium ion batteries.The charge distribution at the interface between liquid electrolytes and solid electrodes, the so-called electrochemical double layer (EDL), plays a key role in the redox kinetic processes in electrochemical devices for energy conversion and storage. Examples of such devices are fuel cells, rechargeable batteries and super-capacitors. EDLs are formed in a large diversity of forms in these devices, depending on the chemical composition of the electrolyte and the electrode. Electrolytes can have different levels of complexity, as they can be formed by high concentrated ionic solutions (e.g. in lithium ion batteries 1 (LIBs)), moderate concentrated and diluted ionic solutions (e.g. in lithium air batteries 2 (LABs)), mixed media involving ions, solvents and charged polymers (e.g. in polymer electrolyte membrane fuel cells 3 (PEMFCs)) or ions, solvents and additives (e.g. in LIBs), 4 and ionic liquids (e.g. in super-capacitors 5,6 (SCs)). Electrodes can be made of metallic oxide semi-conductors (e.g. in LIBs) 7 or metallic catalysts (e.g. in PEMFCs). 8,9 In these systems, the charge distribution within the EDL is generally time-dependent and affects the effectiveness of the redox reactions (e.g. conversion reactions in batteries) taking place on the electrode, and it is conversely affected by the redox reactions on the electrode and the ionic transport properties of the electrolyte. 10 For instance, it seems unclear how much EDL effects affect the performance of electrochemical devices, as the discharge and charge dynamics of LIBs for example. 11 Furthermore, still in the case of LIBs, understanding these interfacial processes is crucial for tackling the problem of the Solid Electrolyte Interphase (SEI) formation and growing kinetics. 12 Similar questions arise regarding the role of the liquid/solid interfaces onto the electrolyte decomposition kinetics in LABs. 13 Frumkin and coworkers were the first suggesting that EDL and the effectiveness of the redox reactions affect each other. 14 They have also demonstrated that this strong relationship arises in a complex dependence of the electrode potential on its ...