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A new low-carbon and environmentally friendly process method for the catalytic synthesis of biodegradable polyesters catalyzed by using ionic liquid catalysts.

A new low-carbon and environmentally friendly process method for the catalytic synthesis of biodegradable polyester by utilizing ionic liquid catalysts.

A novel nanocatalyst design using nanomaterials through active-zone crystallisation was proposed. The hydrothermal crystallisation of amorphous dendritic fibrous nano-titanium dioxide with Ni (DFNT/Ni) sites was determined to be the main step in producing extremely active dendritic DFNT/Ni zones, which in turn dramatically enhanced their catalytic activities. DFNT/Ni was then combined with polyvinyl alcohol (PVA) by using a traditional individual-nozzle electrospinning method, and the resulting material was named PVA-DFNT/Ni. This method was utilised to produce 3-aryl-2-oxazolidinones from ethylene oxide, CO2, and anilines. The prepared catalytic apparatus was eco-friendly and had the advantages of high catalytic activity, ability to improve the reaction mixture, and reusability without a considerable decrease in efficiency. It is extracted in the straight and adoptive chemical fixation of flue-gas CO2 obtained from industrial emissions, thereby achieving high degrees of CO2 absorption and conversion.

The Chinese Fusion Engineering and Testing Reactor (CFETR) has been performed and is in its engineering design stage. Presently, there are two options allowed for the divertors; the helium-cooled stage and water-cooled stage. The water-cooled one has been focused in this article. The configuration of CFETR divertor module was designed. The cassette design scheme and cassette box inner and outer locking systems were introduced, and the locking system was designed to compliant with the remote-handling (RH) requirements. Two divertor RH design options were provided: one is removed through lower port; the other is targets and baffles removed through upper port; supports and cassette were not removed. The other major research was the water cooling channels’ design and its pressure drop calculation. In addition, the fluid, thermal, and mechanical analyses on the outer target were done. Within 10-MW/m2 heat flux, outer target design can ensure that the temperature for all the components works within their temperature limit, and all the components meet the stress design criteria except the copper alloy pipe. The maximum primary stress induced by pressure on the copper alloy pipe appears in the local position between the two monoblocks, which exceeds the design limit. Protection components are need to be added at the gap of the future design optimization to reduce the local stress. After the thermal-hydraulic analysis on water-cooled divertor cassette, the maximum temperature and the maximum stress of cassette meet the requirements. The results of electromagnetic force analysis shows that the deformation on first wall and transition support is less than 0.5 mm, and the maximum stress is also below its tensile strength values. This article summarized the latest achievements in the design and research of CFETR water-cooled diverter in China. All the results will be of great reference for the CFETR divertor optimal design.

In order to construct virtual land environment for virtual test, we propose a construction method of virtual land environment using multi-satellite remote sensing data, the key step of which is accurate recognition of ground object. In this paper, a method of ground object recognition based on hyperspectral image (HSI) was proposed, i.e., a HSI classification method based on information measure and convolutional neural networks (CNN) combined with spatial-spectral information. Firstly, the most important three spectra of the hyperspectral image was selected based on information measure. Specifically, the entropy and color-matching functions were applied to determine the candidate spectra sets from all the spectra of the hyperspectral image. Then three spectra with the largest amount of information were selected through the minimum mutual information. Through the above two steps, the dimensionality reduction for hyperspectral images was effectively achieved. Based on the three selected spectra, the CNN network input combined with the spatial-spectral information was designed. Two input strategies were designed: (1) The patch surrounding the pixel to be classified was directly intercepted from the grayscale images of the three selected spectra. (2) In order to highlight the effect of the spectrum of the pixel to be classified, all the spectral components of this pixel were superimposed on the patch obtained by the previous strategy. As a result, a new patch with more prominent spectral components of the pixel to be classified was obtained. Using the two public hyperspectral datasets, Salinas and Pavia Center, the experiments of on both parameter selection and classification performance were performed to verify that the proposed methods had better classification performance.

In the EAST experiment, the extent of damages of the divertor is different in toroidal direction. One of the reasons is uneven of heat load of toroidal distribution, which may be caused by geometric errors of the divertor surface. The EAST lower divertor is cooled by 8 toroidal active water-cooling branches, and calorimetric system estimates the heat load and its distribution by measuring the cooling water temperature difference and flow rate. The non-uniformity of the heat load of 8 branches is -3.5% ∼ 4.5%. Besides, using the Leica AT960 / AT401 laser tracker to measure the profile deviation of the upgraded lower divertor, the non-uniformity of the geometric accuracy is -15% ∼ 25%. Besides, it's found that the annular heat load distribution is positively correlated with the comprehensive deviation of the divertor surface. The correlation coefficient is about 15%, and at least seven of the eight divertor regions meet this characteristic.

Baking is an important wall conditioning method that is widely used in tokamak devices to obtain high quality plasma discharges. In order to create a theoretical analysis method for the baking of tokamak plasma facing components (PFCs), the COMSOL Multiphysics software is used to establish and solve a series of the heat transfer models of the experimental advanced superconducting tokamak (EAST) PFCs, as a representative calculation case. The thermohydraulic measurement system (including the temperature, pressure and flow sensors) is successfully installed on EAST to verify the accuracy of the heat transfer model, as a calorimetry verification example. The uncertainty of this analysis method as compared to the experimental results is less than 5% and the robustness of this analysis method is satisfied. These heat transfer models are used to obtain the temperatures on the surface, the internal temperature distributions of the components, and the internal temperature and velocity distributions of the cooling ducts numerically. The significance of these parameters for the fusion reactor design is discussed in detail. This analysis method is an important component of the fusion reactor thermohydraulic analysis method (FRTHAM), and it provides an accurate computing method for fusion reactor baking analysis.

This study features the application of artificial neural network for prediction of surface tension of branched alkanes. Surface and interfacial tensions of alkanes show a specific interaction betwe...

This article concentrates on the optimized design about the structures of the stator in linear induction motors, with the aim of reducing end effects. When the linear induction motor is operating at high speed, the induced eddy current generated by the secondary conductive plate will distort the air gap magnetic field and increase the loss of the linear induction motor. Established in the short primary two-sided linear induction motor, three types of stator optimization schemes are compared and analyzed, and the forward extension triangle slot is taken as the final optimization scheme. The results indicate that adopting the stator slot scheme of forward, expanding triangle can reduce the air gap magnetic field distortion and increase the electromagnetic force of the linear induction motor. Ultimately, the finite element software is used to optimize the parameters to further improve and improve the stator structure of the linear induction motor. The work of this paper is chiefly to provide a new design idea for reducing the end effect of linear induction motors.

Lower divertor, as the most critical part of experimental advanced superconducting tokamak (EAST), has functions of protecting the vacuum vessel, particles exhausting, and heat load handling. Doped graphite with SiC coating is adopted as plasma-facing material, which is bolted to active water-cooling heat sink by an M8 screw with a soft graphite sheet inserted between graphite tile and heat sink to improve the capacity of heat transmission currently. In order to guarantee excellent performance of lower divertor, every striking target, which contains 27th graphite tiles, must be inspected for its assembly quality before being installed in EAST device. This paper introduces a rapid nondestructive inspection method for EAST lower divertor by infrared (IR) thermography. The poor assembly quality, such as unevenness of contact surface of graphite tile or heat sink, overlap of the soft graphite sheet, and unqualified values of torque, can be detected qualitatively by comparison of the surface temperature evolution of graphite tiles in symmetric positions of the same divertor target when water flowing in the tube welded into heat sink is changed from hot to cold. The 3-D thermal finite-element analyses are performed to simulate the case of target with excellent assembly quality and defect-free tiles and as a reference for the experimental observations obtained by IR thermography eventually.

In this study, mechanisms of reduction reaction of carbon dioxide on Iron doped silicon nanocage are investigated in gas phase and water. The metal catalysts have several fundamental problems such as slow kinetics, high over potential, low performance and insignificant selectivity. The reaction pathways of carbon dioxide conversion to methanol are examined by theoretical methods in gas phase and water. The acceptable reaction pathway is identified from thermodynamic view point in gas phase ad water. Results indicated that the in carbon dioxide conversion to methanol the reaction step of 4 is the rate-limiting step. Results indicated that the over potential (−0.825 V) of reaction steps in gas phase and water is lower than metal catalysts (−1.116 V). The Iron doped silicon nanocage with low barrier energies and low over potential is proposed as efficient catalyst in gas phase and water.

EAST (Experimental Advanced Superconducting Tokamak) device is a D-shaped full superconducting tokamak with actively water cooled plasma facing components. As the EAST project technical risk control and possible failure mitigation approach, RAMI (Reliability, Availability, Maintainability and Inspectability) analysis was required for the upper full tungsten divertor water cooling system, which insures the system to cool the PFCs with high efficient and safety without leakage. At the same time the cooling water could be at suitable pressure, temperature and velocity, water parameters of cooling circuit also could be monitored. A functional breakdown was prepared and all functions are described using the IDEFO (Integration DEfinition Function – language O) method. FMECA (Failure Mode, Effects and Criticality Analysis) was performed to the system initial risk. There are 31 risks for the initial state, including 7 major risks. No major risk remains after taking into account all the actions. RBDs (Reliability Block Diagrams) were prepared to calculate the reliability and availability of each function. The initial availability of upper divertor cooling water system was 93.63%, after optimization the expected availability was 98.56% over 11,520 h. It was assessed that the upper full tungsten divertor water cooling system RAMI analysis results meet the EAST project requirement during this design phase and the results will be qualified further when the system design is updated.

In the Experimental Advanced Superconducting Tokamak (EAST), the water in the cooling channels of the upper divertor is difficult to be pushed out by the current drainage system resulting in the possible divertor damage. Therefore, studies on the draining process using the gas pushing for this divertor is essential to improve the current drainage system. In this paper, the hydraulic characteristics of the developing gas-liquid two-phase flow were investigated in detail by using the FLUENT code. The results showed that the pressure difference between the inlet and outlet of the cooling channel should be larger than 4 kPa to effectively blow out the residual water from the cooling channels by the nitrogen gas pressure. Also, it was found that the draining process can be divided into five stages in regards to the different hydraulic characteristics, such as the flow velocity, the draining water flow rate, and the pressure distribution. These results will provide a theoretical basis for future improvements in the EAST drainage systems.

During long-pulse plasma operation with high power in tokamak, excessive heat load on divertor may lead to material melting or erosion of the first wall material, which enhances impurity radiation and degrades plasma performance. As an important component of the first wall, divertor cooling system is important for the high power and stable operation of the device. The Experimental Advanced Superconducting Tokamak (EAST) is committed to achieving more than 400 s long-pulse H-mode operations, which is equipped with a first wall of full metal. The 10 MW/m2 heat load on divertor means a big challenge for the continuous operation of the system, but the current divertor cannot meet the conditions, so it needs to be upgraded. In order to check whether the cooling water system of the new divertor in EAST can meet the requirements, a fluid test was built to measure the flow rate and flow drop of the divertor. The results show that the difference between the test results and the results of ANSYS-based simulation is 9 %, and the maximum difference between the results of the comparison of two different model parts is 3 %. It is concluded that the cooling water system of the divertor in EAST can achieve the heat load and safety requirements.

Nuclear fusion is now the ultimate need for energy, tokamak is one of the possible devices for controlled nuclear fusion. Based on the advanced tokamak magnetic confinement configuration and the research results of fusion physics in recent decades at home and abroad, Chinese Fusion Engineering Test Reactor (CFETR) will carry out innovative physical design to achieve the international requirements. Divertor is an essential component of the magnetic confinement fusion device, which directly sustains the strong particle flow and high heat load. The cooling system of divertor will directly affect whether divertor can function properly. In this paper, a new structure of divertor suitable for CFETR is designed and simulated, both the flow field analysis and the heat transfer analysis of the model were verified. The results show that the designed divertor structure can meet the system requirements.

Linear induction motors (LIMs) are transmission devices that can convert electric power to mechanical work in the form of translational motion. As the rotor of LIM is of such characters as cut-off ends and big air-gap length, which brings a phenomenon known as the end effect. In order to solve this problem, a calculation program of equivalent circuit of LIM is designed based on equivalent circuit method and the unique end effect of LIM in the paper. Finally, the finite element method is used to verify it.

In this paper, propagation characteristics of the 8.7/10kV XLPE cable with joints are investigated by using the CST software. Establishing multiple cable joints model based on finite integral method, it focuses on the relationship between attenuation constant and phase velocity. The simulation results show that the phase velocity is violently shaken with the huge change of attenuation constant in low frequency. It is worth mentioning that in the frequency range from OGHz to 1GHz, there are two frequency bands with little change of phase velocity, which are range from 250MHz to 350MHz and from 650MHz to 850MHz. Since the attenuation constant is not large in the low frequency range from 250MHz to 350MHz, the Signal-to-Noise Ratio is high. It will be helpful to improve the accuracy of partial discharge detection if selecting the signal in this frequency range.

This paper presents two pieces of method about how to improve performance of surfaced-inserted permanent magnet synchronous generator (PMSG). One way is increasing q-axle's synchronous inductance appropriately, this way can reduce voltage regulation rate which is an important point that let permanent magnet synchronous generator can be used widely. The other way is using skewed slot to reduce cogging torque, this can reduce axle's mechanical damage. This paper uses finite element method to build permanent magnet synchronous generator's model and result of calculation shows that the method above can improve permanent magnet synchronous generators' performance exactly.

s The Experimental Advanced Superconducting Tokamak (EAST) aims at more than 400 s long-pulse H-mode operations with a full metal wall and a divertor heat load of 10 MW/m2 in the next machine operation phase. However, currently the lower graphite divertor heat handling capability is restricted to less than 2 MW/m2. Therefore, the lower divertor and lower corresponding components are demanded to be upgraded. The in-vessel plasma facing components (PFCs) cooling water system (CWS) providing water to the lower divertor is important, which requires to meet cooling requirement according to the related heat load of PFCs. This paper describes the latest EAST in-vessel CWS. The conceptual design procedure of the in-vessel CWS for EAST lower tungsten divertor is detailed presented. Hydraulic and structure analysis are performed. The pressure drop is within acceptable range of design requirement. The resultant stress and displacement meet the requirement of the design code and standard. According to the test of EAST lower divertor in-vessel CWS prototype, the test and simulation data are provided to prove that the design is rational and the minor difference of structure and weld have a little effect on water pressure drop. These results show that the design of the in-vessel CWS for EAST lower divertor at present meets the requirements, which give a strong support to the next design phase.

An accurate critical heat flux (CHF) prediction method is the key factor for realizing the steady-state operation of a water-cooled divertor that works under one-sided high heating flux conditions. An improved CHF prediction method based on Euler's homogeneous model for flow boiling combined with realizable k- model for single-phase flow is adopted in this paper in which time relaxation coefficients are corrected by the Hertz-Knudsen formula in order to improve the calculation accuracy of vapor-liquid conversion efficiency under high heating flux conditions. Moreover, local large differences of liquid physical properties due to the extreme nonuniform heating flux on cooling wall along the circumference direction are revised by formula IAPWS-IF97. Therefore, this method can improve the calculation accuracy of heat and mass transfer between liquid phase and vapor phase in a CHF prediction simulation of water-cooled divertors under the one-sided high heating condition. An experimental example is simulated based on the improved and the uncorrected methods. The simulation results, such as temperature, void fraction and heat transfer coefficient, are analyzed to achieve the CHF prediction. The results show that the maximum error of CHF based on the improved method is 23.7%, while that of CHF based on uncorrected method is up to 188%, as compared with the experiment results of Ref. [12]. Finally, this method is verified by comparison with the experimental data obtained by International Thermonuclear Experimental Reactor (ITER), with a maximum error of 6% only. This method provides an efficient tool for the CHF prediction of water-cooled divertors.

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 order to accurately predict the incident critical heat flux (ICHF, the heat flux at the heated surface when CHF occurs) of a water-cooled W/Cu monoblock for a divertor, the exact knowledge of its peaking factors (fp) under one-sided heating conditions with different design parameters is a key issue. In this paper, the heat conduction in the solid domain of a water-cooled W/Cu monoblock is calculated numerically by assuming the local heat transfer coefficients (HTC) of the cooling wall to be functions of the local wall temperature, so as to obtain fp. The reliability of the calculation method is validated by an experimental example result, with the maximum error of 2.1% only. The effects of geometric and flow parameters on the fp of a water-cooled W/Cu monoblock are investigated. Within the scope of this study, it is shown that the fp increases with increasing dimensionless W/Cu monoblock width and armour thickness (the shortest distance between the heated surface and Cu layer), and the maximum increases are 43.8% and 22.4% respectively. The dimensionless W/Cu monoblock height and Cu thickness have little effect on fp. The increase of Reynolds number and Jakob number causes the increase of fp, and the maximum increases are 6.8% and 9.6% respectively. Based on the calculated results, an empirical correlation on peaking factor is obtained via regression. These results provide a valuable reference for the thermal-hydraulic design of water-cooled divertors.

Neonatal hypoxia-ischemia brain damage is an important cause of death by affecting prognosis of neural diseases. It is difficult to find effective methods of prevention and treatment due to the complexity of its pathogenesis. N-methyl-D-aspartate (NMDA), as an excitotoxicity amino acids, has proven to play an important role in hypoxic-ischemic. However, the exact effects of the NMDA subunits, NR2A and NR2B, during hypoxic-ischemic have not been investigated in detail. Therefore, we sought to study whether the NMDA receptor antagonist could confer neuroprotective effects in a neonatal rat hypoxia-ischemia model. The effects of intraperitoneal injections of different drugs, namely MK-801 (0.5 mg/kg), NVP-AAM077 (5 mg/kg), and Ro25-6981 (5 mg/kg), on the expressions of anti-apoptotic protein Bcl-2 and apoptosis protein Bax in the subventricular zone were analyzed by immunohistochemical staining to explore the roles of NMDA subunits (NR2A and NR2B) in hypoxic-ischemic. We found that the NR2B antagonist (Ro25-6981) could inhibit hypoxic-ischemic with the increasing Bcl-2 expression. NR2A antagonists (NVP-AAM077) can increase cerebral hypoxia-ischemia in neonatal rats, promoting the expression of apoptotic protein Bax.

In order to realize safe and stable operation of a water-cooled W/Cu divertor under high heating condition, the exact knowledge of its subcooled boiling heat transfer characteristics under different design parameters is crucial. In this paper, subcooled boiling heat transfer in a water-cooled W/Cu divertor was numerically investigated based on computational fluid dynamic (CFD). The boiling heat transfer was simulated based on the Euler homogeneous phase model, and local differences of liquid physical properties were considered under one-sided high heating conditions. The calculated wall temperature was in good agreement with experimental results, with the maximum error of 5% only. On this basis, the void fraction distribution, flow field and heat transfer coefficient (HTC) distribution were obtained. The effects of heat flux, inlet velocity and inlet temperature on temperature distribution and pressure drop of a water-cooled W/Cu divertor were also investigated. These results provide a valuable reference for the thermal-hydraulic design of a water-cooled W/Cu divertor.

EAST, with full superconducting magnetic coils, has been designed and constructed to address the scientific and engineering issues under steady state operation. It has passive stabilizers with the function of protecting the vacuum vessel, heating systems and diagnostic components from the plasma particles and heat loads. As the vertical plasma motion is unstable in tokamak with elongated D-shape plasma, the passive stabilizers and in-vessel active feedback coils are used for vertical plasma position control in EAST. To accommodate with the new stage for high performance plasma and enhance the control of vertical stabilization in EAST, the project of passive stabilization loop (PSL), connect all the independent passive stabilizers together as a loop, has been accomplished. The PSL consists of 32 passive stabilizers and the current bridges. All the supporting structures of PSL are insulated from the vacuum vessel. The separate passive stabilizers are electrically connected together forming the upper and lower toroidal loops, and then the two loops are electrically connected by the copper current bridges. The current bridges are designed coaxial and symmetrical in order to counterpoise the electromagnetic forces. There are insulation layer and external resistor between the outer and inner bridges to avoid breakdown. What’s more, a stainless steel shell with graphite tiles is covered on the bridges to protect them from the plasma. The total resistance of PSL is reduced to 150 micro ohms by silver plating on the contact surface. As indicated, the PSL was fabricated and assembled successfully and met the design requirement for the plasma operation. With the PSL, the control of the vertical stabilization is improved.

The thermal boundary condition has very important effects on the accuracy of thermal stress calculation of a water-cooled W/Cu divertor. In this paper, phase-change heat transfer was simulated based on the Euler homogeneous phase model, and local differences of liquid physical properties were considered under one-sided high heating conditions. The steady-state temperature field and thermal stress field under nonuniform thermal boundary conditions were obtained through numerical calculation. By comparison with the case of traditional uniform thermal boundary conditions, the results show that the distribution of thermal stress under nonuniform thermal boundary conditions exhibits the same trend as that under uniform thermal boundary conditions, but is larger in value. The maximum difference of maximum von Mises stress is up to 42% under the highest heating conditions. These results provide a valuable reference for the thermal stress calculation of water-cooled W/Cu divertors.

The stromal cell-derived factor 1/C-X-C chemokine receptor type 4 (SDF-1/CXCR-4) axis plays an important role during stem cell recruitment. SDF-1 can also bind the more recently described CXCR-7 receptor, but effects of SDF-1/CXCR-7 signaling on stem cell migrating to ischemic brain injury area are little known. In the present study, we investigated the effect of CXCR-7 on bone marrow mesenchymal stem cell (BMSC) migration toward SDF-1α in the cerebral ischemia/reperfusion (I/R) rat hippocampus. We cultured BMSCs from rats and characterized them using flow cytometry, immunocytochemistry, western blotting, and immunofluorescence to detect SDF-1α, CXCR-4, and CXCR-7 expression in third passage BMSCs (P3-BMSCs). We also prepared the model of transient cerebral I/R by four-vessel occlusion (4-VO), and BMSCs were transplanted into I/R rat brain via lateral ventricle (LV) injection (20μl, 1×10(6)/ml). After that, we examined the effect of BMSCs migration in the cerebral I/R rat hippocampus through Transwell chamber assay. Our results show that SDF-1α, CXCR-4, and CXCR-7 were expressed in P3-BMSCs. Moreover, SDF-1α expression was increased in I/R hippocampus. At 48h after transplant, green fluorescent BrdU-BMSCs were observed in transplant groups, but no green fluorescent BrdU-BMSCs were seen in medium group. Among BMSCs transplant groups, the number of BrdU-BMSCs positive cell was the highest in BMSC group. Treatment with AMD3100 and/or CXCR-7 neutralizing antibody decreased the number of BMSC migration. Collectively, these findings indicate that CXCR-4 and -7 receptors were co-expressed in BMSCs and synergistically promoted BMSC migration. The effect of CXCR-7 was stronger than that of CXCR-4. Moreover, BMSCs that migrated to hippocampus promoted the autocrine and paracrine signaling of SDF-1α.

The neutron wall load ( \(P_{\mathrm{n}})\) of Chinese fusion engineering testing reactor (CFETR) will be less than 1 MW/m2. To meet the net tritium breeding ratio (TBR) of the reactor, a new water-cooled blanket concept is considered. The blanket neutronics schemes are performed to explore the local TBR issues in the \(P_{\mathrm{n}}\) range of 1–5 MW/m2, which aims at the effective design of the blanket concept considering the tritium self-sufficiency. As a result, the calculation results are compared with the local TBR values and the material fraction changes. It is found that the local TBR has the high value at low \(P_{\mathrm{n}}\) while the blanket size in radial direction is determined. It is mainly because of the total breeding area increasing due to the pipe pitch increasing in the model. This leads to the possibility for CFETR using a simplified blanket interior. In addition, to match the pressurized water reactor (PWR) water-cooled condition, a reduced size of blanket module in toroidal direction is achievable. It can be concluded that a PWR water-cooled blanket has more benefits to CFETR engineering implementation in the future.

An effective method for eddy current calculation has been developed for EAST’s new divertor by using ANSYS. A 3D model of a double null divertor for the EAST device was built to evaluate eddy currents and electromagnetic (EM) forces on these components. The main input to the model is the plasma current and poloidal field coil currents, which are loaded into the model using experimental data measured from the EAST discharges. These currents generate magnetic fields that match those producing an EAST discharge, and the time variation of these fields produces the eddy currents in the divertors, along with from the resulting EM forces. In addition, the first 10 time steps were discussed for the eddy current generation and changing trend. It indicates that a static analysis before a transient mode start can solve the eddy current origination in the initial time steps. With this method, the EM transient response of EAST’s new divertor can be predicted based on ANSYS simulations. Furthermore, the method is also an effective approach to estimate the EM results for the in-vessel components of a fusion reactor during a disruption.

This paper demonstrated our discovery of the movement effect of BiFeO3 nanoparticles in solution by strong electrical polarization. First, BiFeO3 nanoparticles were prepared by ball milling and characterized by SEM. Then, the preparation of BiFeO3 solution was finished. BiFeO3 nanoparticles are found to move in solution due to electrical field. The movement velocity of BiFeO3 nanoparticles, which is about 10 μm·s−1, is influenced and controlled by the applied electrical field. The concentration of BiFeO3 solution and the nanoparticle sizes also have effects on its movement properties. The movement of BiFeO3 nanoparticles in solution is induced by strong polarization, and BiFeO3 nanoparticles have net negative electric charges because of the electrostatic force between BiFeO3 nanoparticles and the negative ions in water resolver.