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Abstract: A set of in-vessel saddle coils has been installed on J-TEXT tokamak. They are proposed for further researches on controlling tearing modes and driving plasma rotation by static and dynamic resonant magnetic perturbations (RMPs). The saddle coils will be energized by DC with the amplitude up to 10kA, or AC with maximum amplitude up to 5kA within the frequency range of 1–5kHz. At DC mode two antiparallel 6-pulse phase thyristor rectifiers are chosen to obtain bidirectional current, while at AC mode an AC–DC–AC converter including a series resonant inverter can generate current of various amplitudes and frequencies. The paper presents the design of the power supply system, based on the definition of the power supply requirements and the feasibility of implementation of the topology and control strategy. Some simulation and experimental results are given in the end. [Copyright &y& Elsevier]

Highlights: [•] Flexible LiFePO4/graphene films were prepared first time by a solvent evaporation process. [•] The flexible electrode exhibited a high discharge capacity without conductive additives. [•] Graphene network offers the electrode adequate strength to withstand repeated flexing. [Copyright &y& Elsevier]

Abstract: Graphene composites were prepared by hydrothermal method using titanium dioxide (TiO2) adsorbed graphene oxide (GO) sheets as precursors. Free-standing hybrid films for lithium-ion batteries were prepared by adding TiO2/graphene composites to the polyvinylidene fluoride (PVdF)/N-methyl-2-pyrrolidone (NMP) solution, followed by a solvent evaporation technique. These films were characterized by atomic force microscopy (AFM), X-ray diffraction (XRD), scanning electron microscopy (SEM) and various electrochemical techniques. Flexible films show an excellent cycling performance, which was attributed to the interconnected graphene conducting network, which depressed the increasing of electric resistance during the cycling. [Copyright &y& Elsevier]

Abstract: Bi0.4Ca0.6MnO3 (BCMO) film was epitaxially grown on a (110) SrTiO3 substrate using the pulsed laser ablation technique. The morphologies of the epitaxial films with different thicknesses were considerably different. For the Bi0.4Ca0.6MnO3 epitaxial film with a thickness of 10nm, the morphology was more like islands. As the film thickness increased to 40nm, the island became smaller, and disappeared when the film thickness reached 110nm. The growth mechanism of the epitaxial films depends on film thickness, which has been discussed. The results will shed light on the formation mechanism of BCMO epitaxial films. [Copyright &y& Elsevier]

Abstract: Bi0.4Ca0.6MnO3 (BCMO) film with a thickness of 110nm was epitaxially grown on a (110) SrTiO3 (STO) substrate using pulsed laser ablation technique. The microstructure of the epitaxial films was investigated by transmission electron microscopy (TEM) and high-resolution transmission electron microscopy (HRTEM) in details. Two different kinds of dislocations, one being perpendicular to the BCMO/STO interface, the other being parallel to the interface, have been commonly observed. The formation mechanism for these dislocations has been discussed. All the dislocations are thought to relieve the local strain in the epitaxial film. [Copyright &y& Elsevier]

Abstract: To investigate the interactions between both the static and rotating resonant magnetic perturbations (RMP) and the tokamak plasma, two sets of coils, namely static RMP (SRMP) and dynamic RMP (DRMP), are constructed on the J-TEXT tokamak. SRMP is reconstructed from TEXT-U and mainly produces static m/n =1/1, 2/1 and 3/1 resonant perturbation field, where m and n are the poloidal and toroidal mode numbers, respectively. DRMP, newly designed and installed inside the vacuum vessel, can generate pure 2/1 RMP. DRMP is also designed to operate in the AC mode and can produce rotating 2/1 RMP which will be used to study the tearing mode control. Due to the effect of the eddy current in the vacuum vessel wall, the amplitudes of the 2/1 component will be attenuated to about 1/3.6 of the DC value when the operation frequency is larger than 500Hz. However, DRMP can still provide sufficient large rotating 2/1 perturbation for tearing mode related studies. [Copyright &y& Elsevier]

Abstract: A soft X-ray pulse height analyzer has been designed and installed on the J-TEXT tokamak for measuring the electron temperature and possibly for monitoring the impurity content and concentration. A multi-channel analyzer, a set of amplifiers, and three silicon drift detectors constitute the detection system. An off-line analysis code was developed to analyze the raw data recorded by the system. The system can measure a minimum electron temperature of 400eV, and its routine operation provides electron temperature measurements at three different positions with a temporal resolution of 60ms and channel separation of 18cm. Line radiation from some moderate and high Z impurities are observable by the system. The results show that the intensity of line radiation from heavy impurity ions is inversely proportional to the plasma density under similar discharge conditions. [Copyright &y& Elsevier]

Abstract: Fe-based ferromagnetic [(Fe1− x Ni x )0.75B0.2Si0.05]96Nb4 (x =0, 0.2 and 0.4) bulk glassy alloys (BGAs) with a diameter of 2mm were prepared by copper mold casting. The corrosion behavior of glassy alloy rods obtained was investigated in 0.5M NaCl, 0.5M NaOH and 0.5M H2SO4 aqueous electrolytes, respectively, using weight loss and electrochemical polarization measurements. It was found that the corrosion rates significantly decrease with an increase in Ni content in all examined solutions. The Ni-containing BGAs are spontaneously passivated with wide passive regions and low passive current densities in NaCl and NaOH solutions, but exhibit the active–passive–transpassive behavior in H2SO4 solution. The partial substitution of Ni for Fe results in a considerable improvement on the corrosion resistance of [(Fe1− x Ni x )0.75B0.2Si0.05]96Nb4 BGAs, because of the structural and chemical homogeneousness of the amorphous phase and the effect of Ni on promoting the formation of a passive film. Besides their high glass-forming ability (GFA), excellent soft-magnetic properties and good mechanical performance, which have been reported before, these FeNi-based BGAs also feature rather high corrosion resistance. [Copyright &y& Elsevier]

Abstract: There has been little research on the application of shading devices in the air gap of the Trombe wall in China. Experiments on the thermal performance of an advanced Trombe wall with shading in the air gap was conducted in a passive solar house in Dalian. The thermal performance was investigated with regard to the simultaneous temperatures, heat gain and their acquisition of the Trombe wall. By analyzing experimental data, an investigation was carried out on the heat preservation effect by the shading device on a winter night. The theoretical optimum fixed location of the shading in the air gap for minimizing the heat loss was also discussed. Finally, the influence of shading on improving indoor thermal comfort was discussed using the concept of the building envelope response factor (BER) presented earlier by Lukic [The transient house heating condition—the building envelope response factor (BER). Renewable Energy 2003;28(4):523–32]. [Copyright &y& Elsevier]

Deep-sea soil particles collected from the Pacific C-C area w ere successfully immobilized on commercial AFM cantilever by a home-made test apparatus. Using this modified probe, adhesion force distribution between the deep-sea soil particle and four metals was measured by in situ AFM. The factors influencing the adhesion force were investigated. The adhesion forces between soil particles and the metal surface were ranked in an order of aluminum alloy (5052) < titanium alloy (STi80) < pure titanium (TA2) < titanium alloy (TC4) under same roughness, indicating the self-cleaning property of 5052 is better than the others. Furthermore, the results suggest the adhesion force decreases as the roughness increases within a certain range. The adhesion forces were determined by the surface energy and the contact radius based on JKR contact model. [ABSTRACT FROM AUTHOR]

Electronic structure and magnetism in CoO systems doped with Zn and Ti have been studied by the first-principles calculations. The ground state is an antiferromagnetic insulator in CoO. The Zn-doped CoO becomes ferromagnetic insulators, but the Co 2+ magnetic moment is enhanced due to the Zn incorporation. By introducing one Ti atom into CoO, the conductivity is enhanced by comparing with pure CoO. The system of CoO doped with two Ti atoms on 9 and 11 substitution positions shows a half-metallic character due to the strong hybridization between Ti and Co atoms. Ti 2 Co 14 O 16 systems with Ti atoms at 9, 10 and 9, 16 and 1, 9 positions show the metallic characteristics with a large spin polarization, which can enhance the conductivity of CoO systems. [ABSTRACT FROM AUTHOR]

Abstract: Three-dimensionally macroporous (3DM) polymer membranes based on poly(vinylidene fluoride-co-hexafluropropylene) (P(VdF-HFP)) are simply prepared through etching calcium carbonate (CaCO3) hard template, which was filled in the polymer matrix previously. It is observed, from the SEM images, that some macropores within the obtained 3DM polymer membrane interconnect through many little holes, which would leave the continuous channels for ion transportation in the resultant polymer electrolyte. The 3DM polymer membrane made from the casting solution, in which the mass ratio of CaCO3 to P(VdF-HFP) is 2:1, has a porosity of 73.6%. The resultant 3DM polymer electrolyte (3DMPE) possesses high ionic conductivity of 1.38×10−3 S cm−1 at room temperature and low activation energy for ion transportation of 6.85kJmol−1. The assembled Li/LiMn2O4 cells exhibit good rate and cycling capabilities when using this 3DMPE membrane as a separator. The results suggest the 3DMPE could be promisingly applied in lithium-ion batteries. [Copyright &y& Elsevier]

Abstract: The paper clarified the effect of humidity adjustment of Trombe wall on indoor environment by the experimental comparison between a passive solar cell and a reference cell. Theoretical analysis on indoor humidity adjustment of Trombe wall in the passive solar cell is also performed based on steady moisture transfer theory. Simultaneously, the experiment proved that the passive solar cell could provide a relatively comfortable indoor environment. [Copyright &y& Elsevier]

Abstract: Recent progress of lower hybrid (LH) experiments with new graphite limiters configuration in the HT-7 tokamak is presented. The lower hybrid current drive (LHCD) efficiency can be determined by fitting based on experimental data. Improved particle confinement was observed via LHCD () characterized by the particle confinement time increased about 1.56 times. It is found that runaways are suppressed during loop voltage is decreasing at the flat-top phase of LH discharges. The main limitations of pulse length are presented in long-pulse experiments with new limiter configuration. [Copyright &y& Elsevier]