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Recoil nuclei produce high ionization and excitation densities in organic scintillators leading to reduced light yield via ionization quenching. To improve understanding of the relationship between organic scintillator specific luminescence and the characteristics of the recoil particle, this work evaluates proton and carbon light yield data using ionization quenching models over an energy range of tens of keV to several MeV for protons and 1-5 MeV for carbon ions. Previously-measured proton and carbon light yield data were examined for a variety of commercial and novel organic scintillating media: EJ-309, a liquid with pulse shape discrimination (PSD) properties; EJ-204, a fast plastic; EJ-276, a PSD-capable plastic; and a custom organic glass scintillator developed by Sandia National Laboratories. The canonical model of Birks did not adequately describe the ionization quenching behavior. Models proposed by Yoshida et al. and Voltz et al. provided a reasonable description of the proton light yield of a variety of organic scintillators over a broad energy range, but additional work is needed to extend the models to carbon ions. The impact of stopping power data was also investigated by comparing model predictions using SRIM and PSTAR/MSTAR libraries, and the results show a significant discrepancy for carbon ions. This work enhances understanding of ionization quenching and facilitates the accurate modeling of scintillator-based neutron detection systems relevant for medical physics, nuclear security and nonproliferation, and basic science studies.

Control parameters of classical control system are expected to be online tuned and optimized by intelligent methods, in order to improve performance and help engineers reduce a lot of repetitive work in dangerous and harmful working environments. Main ideas and works of this paper are as follows:Firstly, change ratio based expert PID control method (EA-PID) is proposed to expand range of control parameters. Expert rule table (ERT) of expert PID control method (E-PID) is replaced by change ratio table (CRT) of EA-PID. Adjusted parameters of EA-PID are the results of multiplying change ratios in current adjusting cycle and control parameters in previous adjusting cycle. Secondly, NARX prediction-based NARX-E-PID and NARX-EA-PID are proposed. The NARX neural network is designed as a time series predictor to predict the output of the control system, then control parameters are adjusted according to the predicted output. Thirdly, comparative simulations of all the above methods are implemented to verify the improved effects. Finally, theoretical analysis is provided to ensure the stability of control systems. Effect are as follows: Firstly, comparative simulations verify that the improved methods have faster control speed, smaller steady-state error, less overshoot, and better ability of anti-interference. Secondly, theoretical analysis shows that the unstable control systems with adjusted parameters can be changed into a stable system by stability judgment in each adjusting cycle.

Electrical double layer capacitors (EDLCs) featuring low-cost and solution-processable electrode materials have attracted significant research interest for their green and economical applications in energy harvesting and storage devices. Here, we demonstrate a novel synthetic route for films of an underexplored 3-D hexagonal bismuth chalcohalide, Bi13S18I2, and investigate its potential as the active electrode material in EDLC-type supercapacitors. The synthetic procedure has been optimised and comprises the lowest annealing temperature (150 °C) and the shortest processing time (1 h) currently reported. When integrated in a symmetrical EDLC with an aqueous NaClO4 electrolyte, the Bi13S18I2-based device achieves a remarkable areal capacitance of 210.68 mF cm−2 with 99.7% capacitance retention after 5000 cycles. Both the Bi13S18I2 powder and thin-film electrodes have been characterized through XRD, XPS, Raman spectroscopy, and SEM. The superior stability, low-cost, and facile synthesis of Bi13S18I2 proves its promising potential for supercapacitor applications.

We report the electrochemical applications of hybrid iodobismuthates [C3H5N2]3[Bi2I9] (IMB), [C2H4N3S][BiI4] (ADB) and [C3H5N2S][BiI4] (ATB), as a new type of environmentally-friendly anode for lithium-ion batteries. The materials show impressive Li-storage capacities along with very good rate capabilities and stability. The excellent properties of ATB, ADB and IMB indicate that further development and optimisation of this new family may be possible by further cation tuning within the series.

To meet the requirement of high molar extinction coefficient, broad absorption spectrum, and photo/thermal stability for sensitizers of quasi-solid-state dye-sensitized solar cells (Qs-DSSCs) with reduced film thickness, a novel D-A-π-A configuration organic sensitizer IQ22 was specifically designed, in which the conjugation bridge of cyclopentadithiophene (CPDT) unit was incorporated to widen the light response and enhance molar coefficients for increasing the short-circuit current density (JSC), and the octane chain on CPDT was targeted for suppressing the charge recombination and improving the open-circuit voltage (VOC). As a result, the Qs-DSSC based on IQ22 exhibits very promising conversion efficiency as high as 8.76%, with a JSC of 18.19 mA cm–2, a VOC of 715 mV, and a fill factor (FF) of 0.67 under AM 1.5 illumination (100 mW cm–2), standing out in the Qs-DSSCs utilizing metal-free organic sensitizers.

Metasurfaces are 2D metamaterials composed of subwavelength nanoantennas according to specific design. They have been utilized to precisely manipulate various parameters of light fields, such as phase, polarization, amplitude, etc., showing promising functionalities. Among all meta-devices, the metalens can be considered as the most basic and important application, given its significant advantage in integration and miniaturization compared with traditional lenses. However, the resonant dispersion of each nanoantenna in a metalens and the intrinsic chromatic dispersion of planar devices and optical materials result in a large chromatic aberration in metalenses that severely reduces the quality of their focusing and imaging. Consequently, how to effectively suppress or manipulate the chromatic aberration of metalenses has attracted worldwide attention in the last few years, leading to variety of excellent achievements promoting the development of this field. Herein, recent progress in chromatic dispersion control based on metalenses is reviewed.

Recently, enormous research passion has been devoted to enhance the power conversion efficiency (PCE) of porphyrin sensitizers for dye-sensitized solar cells (DSSCs), but the major stumbling block is the absorption defect in the visible-light region. To address this challenge, high-performance DSSCs are reported based on a new donor-π-acceptor sensitizer FW-1, 7H-dibenzo[c,g]carbazole-substituted and fused zinc porphyrin, co-sensitized with a benzotriazole-containing dye (WS-5) in iodine and cobalt redox systems, and high PCEs of 10.21 and 10.42 %, respectively, were obtained. An unprecedented breakthrough was obtained by making one sensitizer suitable for several electrolyte systems because of its appropriate molecular orbitals and co-sensitizer.