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Hydrogen bonding and the electrostatic shielding effect between cellulose nanocrystals (CNCs) and bis(2-hydroxyethoxy)oleylamine (BOA) enhanced adsorption of surfactant molecules at the gas/water interface and induced gelation within the bulk.

Mastering nuclear fusion, which is an abundant, safe, and environmentally competitive energy, is a great challenge for humanity. Tokamak represents one of the most promising paths toward controlled fusion. Obtaining a high-performance, steady-state, and long-pulse plasma regime remains a critical issue. Recently, a big breakthrough in steady-state operation was made on the Experimental Advanced Superconducting Tokamak (EAST). A steady-state plasma with a world-record pulse length of 1056 s was obtained, where the density and the divertor peak heat flux were well controlled, with no core impurity accumulation, and a new high-confinement and self-organizing regime (Super I-mode = I-mode + e-ITB) was discovered and demonstrated. These achievements contribute to the integration of fusion plasma technology and physics, which is essential to operate next-step devices.

All-inorganic carbon-based perovskite solar cells (C-PSCs) with CsPbI2Br as photosensitizer have attracted great attention due to their low cost, high efficiency, and good stability. However, the CsPbI2Br film prepared by the solution method usually has many defects, which reduces the charge extraction rate and photoelectric performance. In this paper, intermediate gradient annealing and antisolvent ethyl acetate treatment are combined to prepare CsPbI2Br films with good crystallinity and few voids. The surface of the obtained CsPbI2Br film is then treated using tetrabutylammonium iodide (TBAI), which can interact with the Pb-I framework to passivate defect states and extend the carrier lifetime. Finally, the champion power conversion efficiency (PCE) of the optimized C-PSCs with a structure of FTO/SnO2/CsPbI2Br/carbon electrode prepared in the air reach 12.29%. At the same time, TBAI molecules also effectively enhance the stability of the PSCs, and the unencapsulated device can still maintain 90% of the initial efficiency after 300 h of storage in an ambient air atmosphere with a relative humidity of 20%-30%. This work provides a simple and effective strategy for the preparation of cheap, high-performance, and stable all-inorganic C-PSCs under atmospheric conditions, and also increases the feasibility of PSCs commercialization.

The gas-insulated transmission line (GITL), which is an important link between ion source and the power supply system, carries all the ion source and the extraction power supplies (ISEPS) conductors at −400 kV with respect to ground, from high voltage deck (HVD) to the ion source and the intermediate potentials of acceleration grids (AGs). In this article, three insulation schemes of the corner section of the GITL are put forward. Through the finite element analysis, only one scheme satisfies the design requirements. In this analysis, the relationships between the design parameters (the radius and angle of the corner section) and the design guiding principles (maximum electric field strength, equivalent distributed capacitance, and so on) are obtained. According to design requirements, the preliminary design parameters of the corner section are determined: the radius of the corner section can change from 50 to 150 mm and the angle of the corner section is chosen as 90°. In this case, the maximum electric field strength of the GITL decreases from 3.18 to 3.06 kV/mm, the maximum electric field strength of the inner surface of the grounding shell decreases from 1.08 to 0.73 kV/mm, the electric field non-uniformity coefficient decreases from 2.21 to 2.15, and the equivalent distributed capacitance increases from 82.12 to 94.70 pF. The simulation results provide a theoretical basis for the engineering design of the corner section of the GITL.

Recently, deep learning methods have made a remarkable improvement in compressed sensing image recovery stage. In the compressed measurement stage, the existing methods measured by block by block owing to a huge measurement dictionary for the whole images and the high computational complexity. In this work, a novel deep convolutional neural network (DCNN) named Convolutional Measurement Compressed Sensing network (CMCS-net) is proposed for image compressed sensing considering both convolutional measurement (CM) and sparse prior. Different from existing works, the convolution operation is adopted both in the measurement phase and reconstruction phase, which retains the structure information of images much better. Simultaneously, the size of the measurement matrix is no longer limited by data dimensions. Particularly, by unfolding the CM process to analyse a Toeplitz-type matrix, the theoretical support of the convolutional compressed measurement is proposed. In addition, in the recovery phase, the authors consider the sparse prior in nature images by embedding the truncated hierarchical projection algorithm into their architecture to solve the problem of multilayered convolutional sparse coding. Furthermore, extensive experiments demonstrate that their proposed CMCS-net can marvellously reconstruct the images and fully remove the block artefact.

SnO2 (Tin oxide) is one of the most successful electron transport layer (ETL) materials in perovskite solar cells (PSCs) because of its low sintering temperature and simple preparation process. Similarly, carbon-based hole transport material-free PSCs (C-PSCs) have been widely studied because of their excellent stability and low price. Therefore, C-PSCs having SnO2 as ETL can be envisaged as a promising PSCs system for commercial flexible equipment. However, studies on this system are still scarce because of its low power conversion efficiency (PCE). In this paper, the electron lifetime and current (Jsc) of a PSC containing a Li-SnO2/Al2O3 + CH3NH3PbI3/carbon structure are greatly improved by doping lithium into SnO2(Li-SnO2) and sandwiching an Al2O3 interlayer into the Li-SnO2 ETL and CH3NH3PbI3. A PCE of 10.01% is obtained, which is 42.3% higher than a PSC having a SnO2/CH3NH3PbI3/carbon structure. The entire preparation process is very simple and is carried out in an air atmosphere below 200 °C (20–40% humidity).

Bimetal/carbon aerogels have many advantages, such as nano-scale properties, low density, large specific surface area, and high porosity, but their application in dye-sensitized solar cells (DSSCs) as a counter electrode (CE) instead of noble metal Pt is relatively rare. In this paper, a low-cost sodium alginate was used to obtain a Co-Mo bimetal/carbon composite through a simple and controlled carbonization process. Using them as CEs of ZnO-based DSSCs, the filling characteristics of dye can be effectively improved. When the Co2+/Mo2+ molar ratio is 1:3, the photoelectric conversion efficiency of Co-Mo bimetal/carbon composite–based DSSCs is close to the photoelectric conversion efficiency of Pt based, which is considered to be the result of the synergy of the carbon and two metal ions.

The stability of foams is a critical consideration given their numerous applications. Toward this effort, the hydrophobically associating water-soluble polymer (HAWP) was applied together with alky...

Combined with two-dimensional (2D) and three-dimensional (3D) finite element analysis and preliminary experimental tests, the effects of size and placement of the electromagnetic shield of the radio-frequency (RF) ion source with two drivers on plasma parameters and RF power transfer efficiency are analyzed. It is found that the same input direction of the current is better for the RF ion source with multiple drivers. The electromagnetic shield (EMS) should be placed symmetrically around the drivers, which is beneficial for the plasma to distribute uniformly and symmetrically in both drivers. Furthermore, the bigger the EMS shield radius is the better generating a higher electron density. These results will be of guiding significance to the design of electromagnetic shielding for RF ion sources with a multi-driver.

Carbon-based perovskite solar cells (PSCs) have received widespread attention due to their low cost and high stability. The carbon electrode prepared by the doctor blade method easily forms defects at the interface between the perovskite layer, thereby reducing its photoelectric conversion efficiency (PCE). In this study, an easily deformable Co–Ni alloy@carbon aerogel was added between the carbon electrode and the perovskite layer via the grinding process, thereby effectively improving the interface quality and hole transporting ability. Correspondingly, the open-circuit voltage and fill factor of the hole-transport-material-free PSCs were significantly improved. A PCE of 12.71% was achieved, but it decreased to 10.77%, which remained at 86%, after 1296 h in the air. Chronoamperometry, Nyquist characterization, and capacitive effect were used to explain the cause of the hysteresis in the PSCs in detail.

Following an upgrade of the neutral beam injection (NBI) system, obvious synergy between combined NBI and ion cyclotron resonance frequency (ICRF) heating was observed in recent experiments conducted at EAST. To investigate the effects of beam-ions accelerated by radiofrequency (RF) wave, analyses are performed by using TRANSP code based on the experimental results. The calculated results argue that only a small fraction of the ICRF power is absorbed by the beam ions in the ICRF + NBI synergistic heating of the (H)D plasma. To enhance the beam–RF interactions in synergistic heating and achieve high plasma performance of EAST, different experimental conditions, including multiple injection powers and diverse beam injection options, were explored. Beam injected fast ions are passing particles, trapped particles observed when synergy heating between ICRF and NBI. In particular, by varying the injection direction of the beam ions it was observed that more tangential beam yields better synergy in comparison with more perpendicular beam. The neutron emission rate of D–D fusion in tokamaks is improved and less fast ion loss is produced with tangential NBI + ICRF heating. Also, the effect of the ratio P ICRF/P NBI on ICRF + NBI combined heating is demonstrated, the higher power boosts the fusion enhancement. The study of the performed synergistic heating provides an important reference for the subsequent combined NBI + ICRF heating experiments on EAST.

To ensure the uniformity of plasma generated by the ion source in the neutral beam system, a large-area high-current ion source with multi-drivers is designed in the neutral beam system1. When these drivers are simultaneously supplied with alternating current work at the same time, there may be mutual coupling and interference between themselves2,3 due to the small distance between them (about 10 cm), which results in an asymmetric distribution of the RF magnetic field in the driver, thereby affects the normal operation of the RF ion source. In this study, a three-dimensional numerical simulation model of the 2-drivers of the radio frequency ion source was established. The electromagnetic induction between the two drivers was simulated and analyzed via this three-dimensional model. Under different distances, the distribution of the magnetic field in the driver without input which induced by the driver with input is analyzed. This research will provide theoretical support for the distribution of CRAFT's RF negative ion source drivers.

To meet the operating conditions of the high power neutral beam injection long-pulse high power injection heating experiment in the fusion experimental device, making the arc power supply of hot cathode bucket positive ion source realize the feedback control mode by different variables is necessary. 1 For the feedback control system of positive ion source beam line arc power supply, a single operation mode is commonly used. This paper mainly studies the multi-mode integrated control mode, including the feedback control of voltage, current, probe, power, beam current and other variables at the same time.The research contents include the principle and structure of the NBI power supply system, typical main loop topology circuit of auxiliary power supply, power control mode theory, typical controller and main chip devices, etc. 2 The inn ovation of this paper lies in the theory of different variable control modes of arc power supply, and the system has the function of PID adjustment automatically according to the feedback variable. 3 Finally, the optimized output of arc power supply, as well as the stable an reliable operation of long pulse extraction beam, are achieved.

The mismatch of the operating parameters of the NBI ion source of the nuclear fusion experimental device will lead to the instability of the plasma, and maybe cause breakdown in the ion source, which will limit the operation of the NBI long pulse and high power. To stabilize the plasma in the NBI ion source, data from multiple rounds of experiments along with a priori information obtained from a predictive plasma model are used. For the problem of low accuracy of the existing key-values extraction algorithms for experimental data, the OPTICS (Ordering Point To Identify the Cluster Structure) algorithm is used to improve the accuracy of the experimental data extraction, and provide a reference for the failure analysis during the experimental operation. A method based on self-organizing feature map (SOM) and BP neural network is adopted. By training historical data, the pulse width of the NBI ion source beam extraction process is estimated under given parameters to adjust the operating parameters.

As one of the most important auxiliary heating facilities of tokamak, Neutral Beam Injector (NBI) has the highest heating efficiency and clearest operating mechanism. Almost all important tokamak devices in the world are equipped with NBI, including Experimental Advanced Superconducting Tokamak (EAST). The mismatch of the operating parameters of the NBI ion source will lead to the instability of the plasma, and maybe cause breakdown in the ion source, which will limit the operation of the NBI long pulse and high power, and it will even be difficult to heat the plasma in the tokamak. In order to stabilize the plasma in the NBI ion source, data from multiple rounds of experiments along with a priori information obtained from a predictive plasma model are used. This paper proposes a method based on Self-Organizing Map (SOM) and Back Propagation(BP) type neural network to estimate the pulse width during the beam extraction process of the NBI ion source under given parameters by training historical data, and adjust the operating parameters accordingly to reduce the ratio of ion source breakdown. The SOM approach mainly relies on current and voltage sensors's data instead of a priori information, and tries to estimate the beam extraction pulse width with less calculations. A BP neural network is also designed to reduce the uncertainty of the SOM algorithm. The algorithms have been tested on off-line data, obtained from experimental shots at EAST-NBI, Hefei, China.

Commercial carbon-based perovskite solar cells have rapidly developed due to its low cost and long-term stability. However, commercial carbon paste as counter electrode always produces a large number of defects at the perovskite interface, thereby greatly affecting the performance of the perovskite solar cells. In this work, a grinding process is used to compact the thin carbon film. The process effectively eliminates defects and improves the extraction efficiency of holes from the photoexcited layer, resulting in 21.2% increase in the efficiency of the carbon-based perovskite solar cells. In addition, open-circuit voltage decay on the order of tens of seconds is analyzed in detail. A new capacitor-like model is established to successfully explain the hysteresis phenomenon. Perovskite solar cells show 700 h of stability with ground carbon counter electrode.