摘要：
Aqueous zinc-ion batteries (ZIBs) have attracted significant attention for grid-scale energy applications due to their low cost, intrinsic safety, and environmental friendliness. However, the energy density of current ZIBs is impeded by unsatisfactory performance of cathodes, due to their limited areal capacity and low active material loading, especially at extreme environments. Herein, an electrochemical activation strategy is put forward to build high energy density ZIBs by designing a flexible cathode composed of NH4+ pillared ammonium vanadate nanosheets on carbon cloth (NVMCE@CC). The electrochemical activation process with high anodic potential (> 1.5 V vs. Zn2+/Zn) guarantees the effective conversion of low-valent to high-valent vanadium and promotes the utilization of large amounts of vanadium elements in the NVMCE@CC composite. Meanwhile, the pillared NH4+ ions expand the interlayer spacing and enhance the structural integrity through the hydrogen bonding between NH4+ and V-O framework. Consequently, the activated NVMCE@CC cathode with a high mass-loading of-5.2 mg cm-2 delivers large areal capacity (-1.74 mAh cm-2 at 1 mA cm-2) and superior cycling stability (capacity retention of 72.1% after 1500 cycles). Importantly, the flexible cathode shows admirable capacities of 0.52 mAh cm-2 at 60 degrees C and 0.55 mAh cm-2 at -10 degrees C, respectively. Moreover, the NVMCE@CC//Zn@CC quasi-solid-state battery demonstrates excellent safety performance and performs well in extreme situations, including bending, cutting, hammering, and washing. This work provides enlightenment for the development of large-areal-capacity vanadium-based cathode materials for practical ZIBs.
作者机构：
[Lei, Zeyong; Deng, Jian; Lei, ZY; Zhong, Lin] Univ South China, Sch Nucl Sci & Technol, Hengyang 421001, Peoples R China.;[Wang, Guolong; Deng, Jian] Univ South China, Sch Mech Engn, Hengyang 421001, Peoples R China.;[Lei, Jieheng] Univ South China, Sch Elect Engn, Hengyang 421001, Peoples R China.;[Zhao, Mu] China Nucl Ind 24 Construct Co Ltd, Beijing 102400, Peoples R China.
通讯机构：
[Lei, ZY ] U;Univ South China, Sch Nucl Sci & Technol, Hengyang 421001, Peoples R China.
关键词：
304SS;cobalt;deposition;spinel;primary loop
摘要：
The radioactive corrosion products (58)Co and (60)Co in the primary loops of pressurized water reactors (PWRs) are the main sources of radiation doses to which workers in nuclear power plants are exposed. To understand cobalt deposition on 304 stainless steel (304SS), which is the main structural material used in the primary loop, the microstructural characteristics and chemical composition of a 304SS surface layer immersed for 240 h in borated and lithiated high-temperature water containing cobalt were investigated with scanning electron microscopy (SEM), X-ray diffraction (XRD), laser Raman spectroscopy (LRS), X-ray photoelectron spectroscopy (XPS), glow discharge optical emission spectrometry (GD-OES), and inductively coupled plasma emission mass spectrometry (ICP-MS). The results showed that two distinct cobalt deposition layers (an outer layer of CoFe(2)O(4) and an inner layer of CoCr(2)O(4)) were formed on the 304SS after 240 h of immersion. Further research showed that CoFe(2)O(4) was formed on the metal surface by coprecipitation of the iron preferentially dissolved from the 304SS surface with cobalt ions from the solution. The CoCr(2)O(4) was formed by ion exchange between the cobalt ions entering the metal inner oxide layer and (Fe, Ni) Cr(2)O(4). These results are useful in understanding cobalt deposition on 304SS and have a certain reference value for exploring the deposition behavior and mechanism of radionuclide cobalt on 304SS in the PWR primary loop water environment.
作者机构：
School of Software, University of South China, Hengyang, China;School of Mechanical Engineering, University of South China, Hengyang, China
关键词：
Integration Testing;Strategy and Methodology;Grey-Box Approach;GUI Software
摘要：
In this paper, by means of effective testing practices, main strategies of integration testing for GUI software, including differentiating strategy for distinguished system, strategy of personnel organization, incremental testing strategy based on baseline version, testing strategy of circulating loop through the whole life, and the strategy of test suite construction, were briefly investigated. Moreover, for the code analysis, the FTA (Fault Tree analysis) is proposed to deal with the software change in regression testing. For test suite constructing, the constructing methods for baseline version and the incremental change are deeply discussed, in which main points focus on the testing strategy based on “Sheet/Form”, the “Grey-box approach” for integration testing process, and the application of the improved STD (State Transform Diagram) in state testing. At the same time, the suite construction of integration testing for two types, including small scale program and large scale software, is analyzed and discussed in detail. For testing execution, the specific method based on “Cross-testing” is investigated. Concurrently, by a lot of examples, all results of testing activity indicate that these strategies and methods are useful and fitted to integration testing for GUI software.
摘要：
A new method of numerical simulating prediction and decontamination effect evaluation for abrasive jet decontamination to radioactively contaminated metal is proposed. Based on the Computational Fluid Dynamics and Discrete Element Model (CFD-DEM) coupled simulation model, the motion patterns and distribution of abrasives can be predicted, and the decontamination effect can be evaluated by image processing and recognition technology. The impact of three key parameters (impact distance, inlet pressure, abrasive mass flow rate) on the decontamination effect is revealed. Moreover, here are experiments of reliability verification to decontamination effect and numerical simulation methods that has been conducted. The results show that: 60Co and other homogeneous solid solution radioactive pollutants can be removed by abrasive jet, and the average removal rate of Co exceeds 80%. It is reliable for the proposed numerical simulation and evaluation method because of the well goodness of fit between predicted value and actual values: The predicted values and actual values of the abrasive distribution diameter are 057 and 055; the total coverage rate is 26.42% and 23.50%; the average impact velocity is 81.73 m/s and 78.00 m/s. Further analysis shows that the impact distance has a significant impact on the distribution of abrasive particles on the target surface, the coverage rate of the core area increases at first, and then decreases with the increase of the impact distance of the nozzle, which reach a maximum of 14.44% at 300 mm. It is recommended to set the impact distance around 300 mm, because at this time the core area coverage of the abrasive is the largest and the impact velocity is stable at the highest speed of 81.94 m/s. The impact of the nozzle inlet pressure on the decontamination effect mainly affects the impact kinetic energy of the abrasive and has little impact on the distribution. The greater the inlet pressure, the greater the impact kinetic energy, and the stronger the decontamination ability of the abrasive. But in return, the energy consumption is higher, too. For the decontamination of radioactively contaminated metals, it is recommended to set the inlet pressure of the nozzle at around 0.6 MPa. Because most of the Co elements can be removed under this pressure. Increasing the mass and flow of abrasives appropriately can enhance the decontamination effectiveness. The total mass of abrasives per unit decontamination area is suggested to be 50 g because the core area coverage rate of the abrasive is relatively large under this condition; and the nozzle wear extent is acceptable. (c) 2023 Korean Nuclear Society, Published by Elsevier Korea LLC. This is an open access article under the
作者机构：
[Tang, Dewen; Qian, Jian] Univ South China, Sch Mech Engn, Hengyang 421001, Peoples R China.
通讯机构：
[Tang, DW ] U;Univ South China, Sch Mech Engn, Hengyang 421001, Peoples R China.
关键词：
point cloud registration;deep learning;attention mechanism
摘要：
The problem of registering point clouds in scenarios with low overlap is explored in this study. Previous methodologies depended on having a sufficient number of repeatable keypoints to extract correspondences, making them less effective in partially overlapping environments. In this paper, a novel learning network is proposed to optimize correspondences in sparse keypoints. Firstly, a multi-layer channel sampling mechanism is suggested to enhance the information in point clouds, and keypoints were filtered and fused at multi-layer resolutions to form patches through feature weight filtering. Moreover, a template matching module is devised, comprising a self-attention mapping convolutional neural network and a cross-attention network. This module aims to match contextual features and refine the correspondence in overlapping areas of patches, ultimately enhancing correspondence accuracy. Experimental results demonstrate the robustness of our model across various datasets, including ModelNet40, 3DMatch, 3DLoMatch, and KITTI. Notably, our method excels in low-overlap scenarios, showcasing superior performance.
摘要：
In order to minimize the gaps between the direct laser deposition channels and improve the quality and performance of the formed parts, the process of direct laser deposition is utilized in laser additive manufacturing to create sequential, single- and double-channel deposition layers on 304 stainless steel plates. Under the premise of keeping the layer rate and defocusing amount unchanged, this study investigates the effects of laser power, scanning speed, and powder feeding rate on the morphology and inclusions of single- and double-channel deposited layers. The aim is to determine the optimal process parameter values for direct laser deposition of single-layer, single-channel Inconel 738. The effects of the three process parameters on the response values were investigated using a multi-factor, multi-level experimental design. The evaluation indexes for the analysis included the deposited layer wetting angle and aspect ratio. The analysis involved one-way extreme analysis and ANOVA analysis. The optimal process parameters are a laser power of 550 similar to 750 W, a scanning speed of 7 similar to 13 mm/s, and the powder feeding rate was 2.1 similar to 4.33 g/min. At the same time, the relationship between surface tension and gravity was integrated with the spherical coronal model and Young's equation to develop a mathematical model of the direct laser deposition process at a theoretical level. The mathematical model of the direct laser deposition process was utilized to analyze the correlation between the geometric parameters of the cross-section of the deposited layer. This analysis provides a valuable data reference for future Inconel 738 direct laser deposition.
作者机构：
[Li, ZY; Li, Zhenye; Jiang, Yufeng] Univ South China, Coll Mech Engn, Hengyang 421001, Peoples R China.
通讯机构：
[Li, ZY ] U;Univ South China, Coll Mech Engn, Hengyang 421001, Peoples R China.
关键词：
Organic solar cells;Morphology;Additives
摘要：
Bulk heterojunction (BHJ) organic solar cells (OSCs) have achieved rapid development in the past decades, and their power conversion efficiency (PCE) has been improved to nearly 20%. The improvement of PCE is often inseparable from the morphology optimization of the active layer. Using different types of additives in the preparation of active layer is one of the most common strategies to optimize the morphology of active layer. In recent years, the application of additives in OSCs has become a hot research direction in the field of OSCs, but there are still great challenges in the in-depth understanding of the action mechanism of additives. Starting from the importance of morphology regulation for performance improvement of OSCs, this review summarizes the application research progress of additives (including solvent additives and solid additives) in OSCs and the regulation mechanism of active layer morphology. The current problems in the development of efficient additives were also discussed, which can provide guidance for the future development of additives in OSCs.
摘要：
采用1080 nm连续激光器对Q235B碳钢上的锈蚀层进行清洗，研究了激光功率以及清洗速度对清洗后试样的表面宏观与微观形貌的影响，分析了不同工艺参数对粗糙度的影响规律，并对清洗后的试样表面进行截面金相观察、元素含量以及物相分析，并结合电化学分析以及硬度检测发现，在清洗速度恒为100 mm·s-1、激光功率为4 kW时，试样表面粗糙度最小为3.94 μm，Fe含量处于峰值，O含量处于谷值，激光清洗效果最好。当激光功率恒为7 kW、清洗速度由100 mm·s-1增至500 mm·s-1时，试样表面粗糙度先减小后增大，在清洗速度为400 mm·s-1时达到最小为3.68 μm，此时激光单次扫描就能完全清洗锈蚀层，其清洗效率为20.6 m2/h。清洗后的基材表面产生重熔层，这使得锈蚀层清洗后基材表面的耐腐蚀性有相应提高，且其硬度在激光功率为7 kW、清洗速度为100 mm·s-1时相比钢材本身提升接近4倍。在Ansys中建立连续矩形光斑激光清洗模型，并与实验结果对比分析，可以通过该模型为高功率连续激光清洗工艺参数提供选择和效果预估。 In this study, the effects of laser power and cleaning speed on the surface macro- and micromorphology of Q235B carbon steel after the rust layer was cleaned with a continuous laser at 1080 nm, are investigated. Moreover, the effect of different process parameters on roughness is analyzed, and cross-sectional metallographic observations, element content, and compound analysis of the cleaned sample surface are carried out. From hardness test and electrochemical analysis, it is found that the minimum roughness of sample surface is 3.94 μm, and the laser cleaning effect is the best when the cleaning speed is constant at 100 mm·s-1, laser power is 4 kW, Fe content is the highest, and O content is the lowest. When the laser power is constant at 7 kW, and the cleaning speed increases from 100 mm·s-1 to 500 mm·s-1, the surface roughness of the specimen first decreases and then increases. The minimum roughness is 3.68 μm when the cleaning speed is 400 mm·s-1, at which time the laser can completely clean the rust layer in a single scan, and its cleaning efficiency is 20.6 m2·h-1. A remelted layer is generated on the surface of the cleaned substrate, which improves the corrosion resistance of the substrate surface after cleaning the rust layer, and its hardness is approximately 4 times higher than that of the steel when the laser power is 7 kW and the cleaning speed is 100 mm·s-1. A continuous rectangular spot laser cleaning model is created using Ansys software and its results are compared with the experimental results to determine the parameters and estimate their effects for the high power continuous laser cleaning process.
摘要：
Industrial robots need to accurately identify the position and rotation angle of the handwheel of chemical raw material barrel valves during the process of opening and closing, in order to avoid interference between the robot gripper and the handwheel. This paper proposes a handwheel keypoint detection algorithm for fast and accurate acquisition of handwheel position and rotation pose. The algorithm is based on the Keypoint R-CNN (Region-based Convolutional Neural Network) keypoint detection model, which integrates the lightweight mobile network MobileNetV3, the Coordinate Attention module, and improved BiFPN (Bi-directional Feature Pyramid Network) structure to improve the detection speed of the model, enhance the feature extraction performance of the handwheel, and improve the expression capability of small targets at keypoint locations. Experimental results on a self-built handwheel dataset demonstrate that the proposed algorithm outperforms the Keypoint R-CNN model in terms of detection speed and accuracy, with a speed improvement of 54.6%. The detection accuracy and keypoint detection accuracy reach 93.3% and 98.7%, respectively, meeting the requirements of the application scenario and enabling accurate control of the robot's rotation of the valve handwheel.
摘要：
The efficient removal of radionuclide uranium is crucial for sustainable nuclear energy and achieving a zero-carbon loop. In this study, we synthesized MXene/MnO2 nanocomposites and evaluated their ability to adsorb and reduce uranium. The results showed that the nanocomposites achieved a uranium removal rate of 99% and an adsorption capacity of 696 mg/g. Adsorption experiments were conducted under different conditions, including pH, cation, anion, and humic acid, and the uranium removal rate by the composite remained high at 91%, 70%, and 60% under the influence of pH = 4.97, 1.0 mM CaCl2, and 20 mg/L humic acid, respectively. The XRD and SEM analyses revealed that the uranium element was removed by the reduction and fixation of the composite material. These findings indicate that the MXene/MnO2 composite is an effective adsorption cleaning agent for the purification of radioactive nuclear wastewater, which has significant implications for pollution control.
摘要：
To facilitate the effective monitoring of human health and environmental quality, it is essential to develop highquality gas sensors for trimethylamine (TEA) with stable sensing sensitivity and low resistance fluctuations in a wide range of humid atmospheres. To this end, a novel Bubble-like Co3O4 tube was fabricated through a ZIF-67 intermediate-assisted thermal decomposition strategy, and its surface morphology and nanostructure were comprehensively investigated. Furthermore, a systematic comparison of the gas sensing properties between Rodlike Co3O4 and Bubble-like Co3O4 was also conducted. The results demonstrated that the introduction of ZIF-67 intermediate not only decreased the baseline resistance of the Bubble-like Co3O4 sensor but also enhanced its gassensing performance. Specifically, the response value of the sensor fabricated using Bubble-like Co3O4 for detecting 100 ppm TEA at 180 degrees C was around ten times higher than that of the Rod-like Co3O4 sensor, while achieving a low detection limit of 55 ppb. Furthermore, the gas sensor exhibited excellent selectivity and antihumidity stability, with negligible variation in response value even after 30 days, retaining approximately 98 % of the initial value. This remarkable sensing-performance can be attributed to several factors, including the large specific surface area, abundant oxygen vacancies, and efficient Co3+/Co2+ catalyzing. Overall, this work sheds new light on the rational design of high-performance TEA sensing materials for practical applications.
期刊：
2023 5th International Conference on Frontiers Technology of Information and Computer (ICFTIC),2023年:679-682
作者机构：
[Xinlin Wang] College of Mechanical Engineering, University of South China, Hengyang, China;[Jiating Peng; Tiejun Zeng] School of Electrical Engineering, University of South China, Hengyang, China
摘要：
Aiming at the problems of low precision and poor working stability of the microcontroller-based IRIG-B decoder, an FPGA-based IRIG-B decoding design scheme is proposed. Considering the IRIG-B code in the transmission process due to the existence of circuit parasitic effects and random noise, the signal waveform will produce the burr problem, the design is based on the combination of Schmitt trigger and median filter hardware to completely eliminate the burr and noise on the stability of the system, over the Questa simulation experiments verified the decoding accuracy of the scheme and the advantages of stability.
作者机构：
[Luo, Xiao-Qing; Zhu, Weihua; Xu, Xiaofeng; Liu, Qin-Ke; Luo, XQ; Chen, Zhiyong; Wang, Xin-Lin] Univ South China, Sch Elect Engn, Nano Technol & Adv Laser Mfg, Hunan Prov Key Lab Ultra Fast Micro, Hengyang 421001, Peoples R China.;[Li, Yan] Univ South China, Sch Nucl Sci & Technol, Hengyang 421001, Peoples R China.;[Liu, W. M.] Chinese Acad Sci, Inst Phys, Beijing Natl Lab Condensed Matter Phys, Beijing 100190, Peoples R China.;[Wang, Xin-Lin] Univ South China, Sch Mech Engn, Hengyang 421001, Peoples R China.
通讯机构：
[Luo, XQ ] U;Univ South China, Sch Elect Engn, Nano Technol & Adv Laser Mfg, Hunan Prov Key Lab Ultra Fast Micro, Hengyang 421001, Peoples R China.
摘要：
The bound states in the continuum (BICs) in optical metasurfaces have latterly received prominent attention for their ultrahigh quality factors and the promise that they hold for realizing lowthreshold nanolasers, high-harmonic generation, and slow-light devices. In this scenario, the flexible tuning of the BIC is at the heart of multifunctional and tunable metadevices underpinning the central role in the modulation of optical spectral responses. Most BIC-inspired works are limited to single types of BICs modes only affected by the structural perturbation without tunable functionality, while different types of BIC modes have received little attention in manipulating the spectral line shapes in optical metasurface. Here, we show that the simultaneous generation and tailored interplay of two types of BIC modes can empower the realization of tailorable spectral lineshape manipulation in all-dielectric metasurfaces. In particular, the magnetic symmetry-protected BICs and accidental BIC result from the preserved reflection symmetry and geometrical parameter perturbation, respectively. The varied asymmetric parameters and the polarization angle of the incident light are responsible for the generation and interplay of the symmetry-protected and accidental quasi-BIC modes. Additionally, the interplaying quasi-BICs enable the implementation of the dual-wavelength passive optical switches throughout the related telecom bands, and can exhibit the tunable spectral features of different types of Fano resonances and EIT analog-based slow-light effect. These results could offer exploration potential for the development of multifunction and high-performance metadevices.
作者机构：
[Yao, Yuan; Chen, Yong] Univ South China, Coll Mech Engn, Hengyang 421101, Peoples R China.;[Feng, Xiaowei; Luo, Tiegang; Han, Shengli; Zheng, Kaihong] Guangdong Acad Sci, Inst New Mat, Natl Engn Res Ctr Powder Met Titanium & Rare Met, Guangdong Prov Key Lab Met Toughening Technol & Ap, Guangzhou 510650, Peoples R China.
通讯机构：
[Tiegang Luo; Kaihong Zheng] A;Authors to whom correspondence should be addressed.<&wdkj&>Guangdong Provincial Key Laboratory of Metal Toughening Technology and Application, Institute of New Materials, Guangdong Academy of Sciences, National Engineering Research Center of Powder Metallurgy of Titanium & Rare Metals, Guangzhou 510650, China
摘要：
In the field of metal matrix composites, it is a great challenge to improve the strength and elongation of magnesium matrix composites simultaneously. In this work, xTC4/AZ31 (x = 0.5, 1, 1.5 wt.%) composites were fabricated by spark plasma sintering (SPS) followed by hot extrusion. Scanning electron microscopy (SEM) showed that nano-TC4 (Ti-6Al-4V) was well dispersed in the AZ31 matrix. We studied the microstructure evolution and tensile properties of the composites, and analyzed the strengthening mechanism of nano-TC4 on magnesium matrix composites. The results showed that magnesium matrix composites with 1 wt.%TC4 had good comprehensive properties; compared with the AZ31 matrix, the yield strength (YS) was increased by 20.4%, from 162 MPa to 195 MPa; the ultimate tensile strength (UTS) was increased by 11.7%, from 274 MPa to 306 MPa, and the failure strain (FS) was increased by 21.1%, from 7.6% to 9.2%. The improvement in strength was mainly due to grain refinement and good interfacial bonding between nano-TC4 and the Mg matrix. The increase in elongation was the result of grain refinement and a weakened texture.
摘要：
Microstructure refinement and mechanical properties enhancement were achieved by utilizing friction stir processing (FSP) as post-treatment to 6061 aluminum alloy fabricated by wire and arc additive manufacturing (WAAM). FSP led to a significant microstructure refinement and porosity reduction. The average grain size decreased from approximately 128 mu m to about 5 mu m. Because of the refined microstructure and the reduced porosity, the average microhardness, yield strength, and ultimate tensile strength increased by 31.5 %, 23.3 % and 6.0 %, respectively. The elongation difference between the horizontal and vertical direction was reduced from 4.5 % to 1.4 %. The properties anisotropy caused by delamination was weakened by the FSP. This work provides a valid option for the quality assurance of the WAAM process of aluminum alloys.
关键词：
CO2 electrochemical reduction;Cu nanoparticles;Cu-based MOFs;Electrocatalysts;Electrochemical reduction reaction
摘要：
The electrochemical CO 2 reduction reaction (CO 2 ER) is an emerging process that involves utilizing CO 2 to produce valuable chemicals and fuels by consuming excess electricity from renewable sources. Recently, Cu and Cu-based nanoparticles, as earth-abundant and economical metal sources, have been attracting significant interest. The chemical and physical properties of Cu-based nanoparticles are modified by different strategies, and CO 2 can be converted into multicarbon products. Among various Cu-based nanoparticles, Cu-based metal-organic frameworks (MOFs) are gaining increasing interest in the field of catalysis because of their textural, topological, and electrocatalytic properties. In this minireview, we summarized and highlighted the main achievements in the research on Cu-based MOFs and their advantages in the CO 2 ER as electrocatalysts, supports, or precursors.(c) 2023 Published by Elsevier B.V. on behalf of Chinese Chemical Society and Institute of Materia Medica, Chinese Academy of Medical Sciences.
