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As solar cell back contact schemes have improved in recent years, the non-ideal emitter region has become a dominant contributor to overall losses in solar cell efficiency. Our analysis shows that these losses can be greatly reduced by creating a lightly ( 10 µm) is measured by cross-sectional etching and electron beam-induced current measurements. Electrochemical capacitance-voltage measurements are used to measure both the depth as well as the dopant profile resulting from the laser-driven process. We also analyse dislocation defects induced by the large thermal gradients inherent to the laser-based process which would greatly limit the device performance.

Divertor is one of key components of tokamak fusion reactor. The CFETR is China Fusion Engineering Test Reactor. Its divertor will expose to tritium environment and neutron radiation. Materials of the divertor will be radioactived, and cannot be handled by personnel directly. To develop structure which compatible with robots handle for installation, maintenance and removing is required. This paper introduces a conceptual design of CFETR divertor module which compatible with remote handling end-effectors. The divertor module is confined by inner and outer support. The inner support is only confined divertor module radial, toroidal and vertical moving freedom degrees, but not confined rotating freedom degrees. The outer support is the structure that can confine rotating freedom degrees and should also be compatible with remote handling end-effectors.

In this work, trimesic acid was introduced in the preparation of cerium-manganese oxide, and its effect on thermal aging resistibility for catalytic diesel soot elimination was investigated systematically. The prepared catalysts were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), N2 adsorption–desorption, X-ray diffraction (XRD), Raman spectra, X-ray photoelectron spectroscopy (XPS) and H2-temperature programmed reduction (H2-TPR). The experimental results show that trimesic acid addition has no significant effect on the morphologies of cerium-manganese oxide catalyst, and also contribute litter to the suppression of catalyst particles sintering and textual features destroying. In addition, the crystal structure and high-temperature (800 °C) phase separation of CeO2-MnOx solid solution are not improved by the trimesic acid modification. But, noteworthily, trimesic acid assisted synthesis can obviously promote Mn4+ generation and keep up oxygen vacancy concentration and hence improve the product of highly active oxygen species (especially O 2 - ) of CeO2-MnOx catalyst during the thermal aging process. Furthermore, trimesic acid assistance can significantly alleviate the loss of CeO2-MnOx metal-support interaction caused by thermal aging, and maintain the ability to supply active oxygen at low-temperature (approximately 200–400 °C). Finally, after thermal aging at 800 °C for 12 h, the trimesic acid assisted synthesized CeO2-MnOx catalyst shows significantly better catalytic soot oxidation activity. Thus this work reveals that besides stabilizing textual and structural properties, stabilizing and optimizing electronic structure is another feasible pathway to enhance the thermal aging resistibility of CeO2-based soot oxidation catalysts.

In-vessel components of the EAST superconducting tokamak upgraded from full carbon plasma facing material (PFM) to carbon PFM for upper and lower divertor, and molybdenum PFM for other surface in 2011. Carbon tiles were mechanical connected to CuCrZr heat sink can handle heat flux ∼3 MW/m2. EAST was planned to update plasma heating power to 36 MW. After that heat flux to divertor will be up to 10 MW/m2 for steady state operation and 15 MW/m2 for transient. Upgrading divertor accommodate high performance plasma operation requirement is necessary. Tungsten PFM with ITER-like monoblock and flat tungsten technology was developed for EAST upper divertor to handle the high heat flux. To meet tungsten divertor pumping requirement an in-vessel cryo-pump was designed to install in upper divertor area. Type-I edge localized mode (ELM) was observed during EAST plasma operation in 2012. Resonant Magnetic Perturbation (RMP) coils with ITER in vessel coils like insulation technology were developed for the ELM mitigation. Vertical Stability (VS) control coils are also upgrade to ITER-like insulation technology, and coils locations were optimized to obtain more effective instability control.

In the ITER project the cryostat is one of the most important components. Cryostat shall transfer all the loads that derive from the TOKAMAK inner basic machine, and from the cryostat itself, to the floor of the TOKAMAK pit (during the normal and off-normal operational regimes, and at specified accidental conditions). This paper researches the dynamic structure strength of the ITER cryostat during the operation of TOKAMAK. Firstly the paper introduces the types of loads and the importance of every type load to the research. Then it gives out the method of building model and principle of simplified model, boundary conditions and the way of applying loads on the cryostat. Finally the author discussed the analysis result and the strength questions of cryostat, also, the author pointed out the opinions according to the analysis results.

The passive stabilization loop (PSL) is part of the plasma stabilization system built in the EAST. Its purpose is to provide passive feedback control of the plasma vertical instability on short time scales. To accommodate with the new stage for high performance plasma and enhance the control of vertical stabilization in EAST, the project of PSL has been carried out. The eddy currents are induced by the vertical displacement events (VDEs) and disruption. The distribution of the eddy currents depend on the structure of the PSL and the formation of the induction. The global model is created and meshed by the ANSYS software. Based on the simulation of plasma VDEs and disruption, the distribution and decay curve of the eddy currents on the PSL are obtained. The stress and the strain caused by the eddy currents and the magnetic field are calculated. To decrease the resistance of the joint and enhance anti-corrosion of the joint surface, the silvered craft is used. In the experiment of test model, the resistance is decreased to half after silvered with the same matrix material and under the same preload. The PSL is insulated from the vacuum vessel at the supports of passive stabilizers. The insulation structure is designed and tested with ceramic material. The PSL is designed, fabricated and assembled with the total resistance 150 μΩ. It can supply passive feedback control to the plasma by the eddy currents induced by the VDEs, which could enhance the vertical placement control of plasma.

On EAST Tokamak, DC glow discharge (GDC) is developed to clean the first wall of plasma. It can effectively control the recycling of H, C, O impurities and improve the wall conditions. There are four GDCs which distribute equally on the EAST Tokamak vacuum vessel wall. Each GDC is equipped with an anode, a stainless steel cover and four support legs. The anode is insulated from cover with Al2O3 ceramics. After a round of experiment, the value of insulation resistance of GDC decreases remarkably due to metallization. To protect the insulation parts and heighten the reliability, ceramic protection covers are used on the GDCs. The other measures which can heighten insulation grades are also taken. After upgrade, the insulation resistance of each GDC between anode and ground is raised highly. When the pressure reaches 4 Pa, H2-GDC and He-GDC is strarted. Boronation and siliconization are also applied to the device wall conditioning. After GDC cleaning, the impurities and partial pressure of remainder gases in vacuum vessel (VV) is decreased greatly and vacuum degree of VV can reach high easily.

The first wall in Experimental Advanced Superconducting Tokamak (EAST) has used many graphite tiles to face the plasma. All graphite ties have been mounted on heat sink using screw bolts which had been preloaded to produce clamp force. The clamp force is very important to keep the graphite tiles on the surface of the heat sink tightly because the heat flux will cross this contacting surface in a small thermal resistor. Without the clamp force the small gap between graphite tiles and heat sink will lead thermal power cannot be carried away by cooling water. The worse is some bolts turned out with the loss of clamp force. From the mathematical models the process of the loss of clamp force has been studied. Research results explain how the different thermal expansion of three members of the screw joint leads to the clamp force decrease to zero under temperature rise and external force and how the stiffness affect the relationship between the clamp force and temperature. The research also gets the critical temperature point that the clamp force can remain above zero. Research results indicated this screw joint is absolute to lose their clamp force during the EAST running so that the bolt joints should be redesign to improve its reliability.

EAST plasma facing components (PFCs) have the function of protecting the vacuum vessel, heating systems and diagnostic components from the plasma particles and heat loads, and also additional to this particles and heat loads handling. The PFCs are designed up–down symmetry to accommodate with both double null and single null plasma configuration. All PFCs use graphite tile for plasma facing surfaces affixed to copper alloy heat sink considering economical factor. Based on this structural design, detailed structural and thermal analysis had been carried out. A special deep hole drilling technology was developed to drill cooling channels directly on heat sink for high efficient heat removal. A dry lubricate material is used between stainless steel support and heat sink for the purpose of absorption of thermal expansion. And analysis results show that the present PFCs need to be improved for the next stage of steady state operation. The PFCs are installed in the vacuum vessel together with in-vessel coils, cryopump and diagnostic components. The design, analysis, manufacture and assembly have been finished. As indicated, all the in-vessel components were fabricated and assembled successfully and meet the design requirement for the plasma operation.