期刊：
Journal of Materials Chemistry A,2024年 ISSN：2050-7488
通讯作者：
Ju, J;Qian, XT
作者机构：
[Huang, Chenhui; Kang, Xiaomin; Zhang, Meng] Univ South China, Coll Mech Engn, Hengyang 421001, Peoples R China.;[Zhai, Zhaofeng] Chinese Acad Sci, Inst Met Res, Shenyang 110012, Peoples R China.;[Ju, Jiang] City Univ Hong Kong, Ctr Adv Nucl Safety & Sustainable Dev, Hong Kong 999077, Peoples R China.;[Qian, Xitang; Qian, XT] Hong Kong Univ Sci & Technol, Dept Chem & Biol Engn, Kowloon, Hong Kong, Peoples R China.
通讯机构：
[Qian, XT ] H;[Ju, J ] C;City Univ Hong Kong, Ctr Adv Nucl Safety & Sustainable Dev, Hong Kong 999077, Peoples R China.;Hong Kong Univ Sci & Technol, Dept Chem & Biol Engn, Kowloon, Hong Kong, Peoples R China.
摘要：
Nanofluidic ion regulation membranes have emerged as versatile platforms for applications in molecular/ion separation and energy conversion. The use of two-dimensional (2D) material-based membranes holds great potential for the regulation of nanofluidic ions owing to their unique properties of surface charges, nanochannels, and nanocapillary force. Herein, a class of 2D flexible ion-conductive membranes with surface charge-controllable and voltage-tunable ion transport properties, which are assembled with monolayered Cd vacancy-containing CdPS3 (vc-CdPS3)-based nanosheets, is reported. Importantly, the ion conductivity of the vc-CdPS3 membrane is several orders of magnitude higher than that of bulk salt solutions up to 0.1 M and reaches a plateau of similar to 10 mS cm(-1) in low concentrated solution (<= 1 mM), demonstrating typical charge-controllable nanofluidic ion transport behavior. This membrane exhibits excellent stability and maintains an ion conductivity of 23 and 20 mS cm(-1) under harsh acidic and alkaline conditions, respectively. By applying positive/negative gating voltage, ion transportation within the vc-CdPS3 membrane is tuned, resulting in low/high ion conductivity. The voltage-tunable behavior across a broad spectrum of cations with varying sizes and charges is observed, showcasing the ion-specific switch ratios of 12 and 10 for potassium and sodium ions, respectively, under an applied voltage of 2 V/-2 V. This work demonstrates the potential of vacancy-containing membranes for a variety of membrane separation applications and offer a strategy for preparing efficient ion transport devices.
通讯机构：
[Zhu, HM ] U;Univ South China, Sch Mech Engn, Hengyang 421001, Hunan, Peoples R China.;Hunan Prov Key Lab Adv Laser Mfg Technol, Hengyang 421001, Hunan, Peoples R China.
关键词：
distortion;laser repairing;microstructure;properties;scanning strategy;temperature distribution
摘要：
In order to explore the effects of scanning strategies on the distortion and properties of laser-repaired thin-plate components, four commonly used strategies, including continuous raster scanning strategy, continuous orthogonal scanning strategy (COS), subarea W-type scanning strategy and subarea leap-type scanning strategy, were applied for laser-repairing thin-plate 2Cr13 steel. The finite element simulation and experimental results show that the temperature field of the laser-repaired layer prepared by COS exhibits symmetrical elliptical characteristic, with homogeneous temperature gradient along all directions. Consequently, the outermost of COS sample exhibits the smallest deformation of 2.86 mm, by avoiding both the unidirectional shrinkage of molten pool and the cumulative effect of longitudinal stress. In contrast, much larger distortion was produced by the other three scanning strategies due to the uneven temperature gradient. Dense martensite without defects was achieved by continuous scanning, while the coarsen martensite occurred by using subarea scanning. The repaired layer by using subarea scanning exhibits lower microhardness of 585-590 HV0.2 and poor wear resistance of 1.45 x 10-5-1.48 x 10-5 mm3/N m, in comparison to 613-618 HV0.2 and 0.9 x 10-5-0.92 x 10-5 mm3/N m obtained by using continuous strategy. COS is the most ideal strategy in laser-repairing thin-plate 2Cr13 steel in this work, exhibiting the lowest distortion as well as the highest microhardness and wear resistance.
期刊：
Physica Status Solidi-Rapid Research Letters,2024年18(2):2300334- ISSN：1862-6254
通讯作者：
Huo, SY
作者机构：
[Fu, Chun-Ming; Li, Hong-Kang; Huo, Shao-Yong; Yao, Long-Chao] Univ South China, Coll Mech Engn, Hengyang 421001, Peoples R China.
通讯机构：
[Huo, SY ] U;Univ South China, Coll Mech Engn, Hengyang 421001, Peoples R China.
关键词：
defect states;elastic valley edge states;power dividers;rainbow trapping;topological phononic crystals
摘要：
Topological phononic crystals (PnCs) with topologically protected boundary states have important applications in the fields of acoustic wave transmission and control. However, previous studies based on solid-state PnC systems are mostly limited by fixed structures, resulting in the difficulty to deform the edge states, which partly limits its practical applications. Herein, a 2D solid topological PnC coupled with the defect is designed to achieve the adjustable valley edge state and rainbow trapping. First, by breaking the spatial inversion symmetry, the valley Hall phase transition of elastic wave is realized and valley edge states are obtained. Next, by introducing defects of different widths between the two different valleys' topological PnCs, both the defect-adjusted valley edge state and defect state are achieved. Then, by designing different topological PnCs waveguides, the robust transport characteristics of the two above states are compared. Subsequently, a new power divider based on the defect-adjusted valley edge state is designed, which is found to possess various manners of operation such as equal and unequal power divisions. Finally, based on defect adjustment of the edge states, a rainbow trapping is implemented. This research provides an important guidance for ultrasonic devices, such as waveguides, energy harvesters, and power dividers. By introducing the line defects in the topological domain wall for the elastic wave, the defect-adjusted valley edge states and defect states are presented, which further are applied to design the novel elastic ultrasonic devices, such as the equal or unequal power dividers and the rainbow trapping effects.image & COPY; 2023 WILEY-VCH GmbH
关键词：
Ti alloys;surface nitriding;microhardness;wear resistance;high-temperature oxidation resistance
摘要：
Titanium alloys are considered lightweight alloys and are widely applied across various industries. However, their low hardness, poor wear resistance, and limited oxidation resistance restrict their prospects for wider application. In this paper, nitride coatings were prepared using three preparation processes, namely laser surface nitriding (LSN), physical vapor deposition (PVD), and plasma ion implantation (PII). Their microstructure, microhardness, tribological behavior, and high-temperature oxidation characteristics were compared. The experimental results revealed that nitrided coatings were successfully prepared using the three methods. However, a comparison of these data shows that the LSN coating exhibited superior comprehensive performance. It achieved the maximum thickness within the shortest preparation time: the thickness was about 280 mu m and the deposition rate of the LSN method was 2250 and 90,000 times higher than those of the PVD and PII methods. Nitrides have high hardness, but the carrying capacity could be attributed to the thickness of the coatings: the PVD coating could withstand a force of 500 g, while the PII coating only withstood a force of less than 25 g. In addition, as hardness is the most important factor for excellent wear resistance, the average volumetric wear rate of the LSN and PVD coatings was about 9 x 10-6 mm3/m center dot N, and their relative wear resistance was 49.2 times that of Ti6Al4V. Meanwhile, the excellent bond between the LSN coating and the substrate was evidenced by a high-temperature oxidation test during a rapid heating-cooling cycle.
作者机构：
[Yu, Miao; Guo, Xin; Zhang, Kai] Sichuan Univ, Sch Mech Engn, Chengdu 610065, Peoples R China.;[Yu, Miao; Guo, Xin; Zhang, Kai] Sichuan Univ, Yibin Ind Technol Res Inst, Yibin 644000, Peoples R China.;[Kang, Xiaomin] Univ South China, Sch Mech Engn, Hengyang 421001, Peoples R China.;[Zhang, Song] Moutai Inst, Dept Food Sci & Engn, Renhuai 564502, Guizhou, Peoples R China.;[Qian, Lu; Qian, L] South China Univ Technol, Sch Mat Sci & Engn, Guangzhou 510641, Peoples R China.
通讯机构：
[Zhang, S ] M;[Qian, L ] S;Moutai Inst, Dept Food Sci & Engn, Renhuai 564502, Guizhou, Peoples R China.;South China Univ Technol, Sch Mat Sci & Engn, Guangzhou 510641, Peoples R China.
摘要：
Hyaluronic acid (HA), a vital glycosaminoglycan in living organisms, possesses remarkable mechanical and viscoelastic properties that have garnered significant attention in therapeutic, biomedical, and cosmetic applications. However, a comprehensive picture of the physicochemical and biocharacterization of HA at the single-molecule level remains elusive. In this work, atomic force microscopy (AFM)-based single-molecule force spectroscopy (SMFS) and molecular dynamics (MD) simulation were used to investigate the nanomechanics and water retention properties of HA at the single-molecule level. The present study aims to unravel the intricate details of the influence of molecular structure on HA behavior and shed light on its unique attributes. According to the force measurements, the energy used to stretch a HA chain in water is 8.45 kJ/mol, significantly surpassing that of Curdlan (3.45 kJ/mol) and chitin (2.23 kJ/mol), both of which possess molecular structures partially similar to that of HA. Intriguingly, the strength of the intrachain interaction of HA (5.54 kJ/mol) was considerably weaker compared to Curdlan (11.06 kJ/mol) and chitin (or cellulose, 10.76 kJ/mol). This result indicates that HA exhibits a preference for interacting with water rather than with itself, thereby showing enhanced water affinity. Moreover, the force measurements demonstrated that changing the glycosidic bond from β-(1-3) (Curdlan) or β-(1-4) (chitin or cellulose) to β-(1-3) + β-(1-4) (HA) resulted in polysaccharides displaying improved water affinity and more extended conformation. These conclusions were further verified by molecular dynamics (MD) simulations. Overall, our work sheds new light on the nanomechanics and water retention properties of HA at the single-molecule level, offering valuable insights for future research in this field.
摘要：
Mining can provide abundant resources, but it also causes heavy metal wastewater pollution, which poses a serious threat to aquatic ecosystems. In this study, Cypridopsis vidua was used as the test organism to investigate the single and combined acute toxicity of common heavy metals (such as chromium (Cr) and nickel (Ni)) in mining wastewater. Then, a random forest model (RF model) was used to predict the combined toxicity of chromium and nickel. Single acute toxicity experiments showed that the 96 h-LC(50 )values of the Cr and Ni for Cypridopsis vidua were 0.81 mg/L and 4.3 mg/L, respectively. aCr was more toxic than Ni. Furthermore, the combined acute toxicity experiments demonstrated that the toxicity of Cr-Ni was higher than Ni but lower than Cr. The predicted results of the RF model were highly consistent with the experimental results of the Cr-Ni combined acute toxicity. So, the model has accurate toxicity prediction ability.
作者机构：
[Chen, Nan; Yuan, Tie-chui; Li, Zhi-you] Cent South Univ, State Key Lab Powder Met, Changsha 410083, Peoples R China.;[Teng, Hao; Chen, Long-wei] Univ South China, Coll Mech Engn, Hengyang 421001, Peoples R China.
通讯机构：
[Li, ZY ] C;[Teng, H ] U;Cent South Univ, State Key Lab Powder Met, Changsha 410083, Peoples R China.;Univ South China, Coll Mech Engn, Hengyang 421001, Peoples R China.
摘要：
With high-energy wet ball milling M2 high-speed steel (HSS) powder and ferrovanadium alloy, an in-situ synthesized core-shell MC carbides reinforced M2 HSS was prepared via vacuum sintering. The phase, morphology and composition distribution of the milled composite powders, and the evolution of the sintered microstructure with the temperature and the associated mechanical properties before and after heat treatment were investigated. The ground powders were fully refined into lamellae and aggregates with V-element evenly distributed inside. Almost full densification (similar to 99.2% relative density) of the modified M2 steel was achieved at 1180 degree celsius by supersolidus liquid phase sintering. Near-spherical MC carbides and irregular M6C carbides were dispersed within the HSS matrix, and the MC developed a core-shell structure due to the solidification of the sintering liquid. Both the matrix grains and carbides of the sintered alloy had been refined by heat treatment, reaching satisfactory bending strength of 3580 MPa and hardness of HRC58, and enhancing the scratch resistance significantly.
期刊：
Engineering Analysis with Boundary Elements,2024年160:45-51 ISSN：0955-7997
通讯作者：
Dong, YQ
作者机构：
[Dong, Yunqiao; Sun, Hengbo; Tan, Zhengxu; Dong, YQ] Univ South China, Sch Mech Engn, Hengyang 421001, Peoples R China.
通讯机构：
[Dong, YQ ] U;Univ South China, Sch Mech Engn, Hengyang 421001, Peoples R China.
关键词：
Distance transformation;Domain integrals;Boundary integral equation;Transient heat conduction
摘要：
Accurate estimation of domain integrals is of crucial importance for the pseudo-initial condition method applied in transient heat conduction analysis. When small time step is used, the integrand of the domain integral changes dramatically and is close to singular. A straightforward evaluation of the domain integrals using Gaussian quadrature may produce large errors. To improve the computational accuracy of two-dimensional domain integrals in boundary integral equation, a new distance transformation method is presented in this paper. The proposed method takes the time step as the transformation parameter, implementing the new transformation in the radial direction directly. With the new distance transformation method, the integrand of the domain integral can be smoother, thus more accurate results can be obtained. Numerical examples have demonstrated the efficiency and accuracy of the proposed method.
摘要：
In this study, a hierarchical Fe2O3-Co3O4 heterojunction with abundant oxygen vacancies was fabricated by a MOF-assisted strategy combing with a thermal treatment process. The morphology, nanostructure and other properties of the synthesized samples were comprehensively investigated by related characterizations. The re-sults display that the Co3O4 modified with Fe2O3 nanorod exhibits an admirable mesoporous structure and abundant oxygen vacancies. In addition, the gas sensing devices were constructed by as-prepared samples and demonstrated that the gas sensor based on Fe2O3-Co3O4 composites shows excellent gas sensitivity of 91.5 to-wards 100 ppm acetone at a working temperature of 200 degrees C, with a short response-recovery time of 20/21 s. Meanwhile, the sensor possesses good reproducibility and long-term stability (over 30 days), and outstanding selectivity towards acetone gas. Exploration into a convincing gas sensing mechanism confirms that fabricating of p-n heterojunction architecture, regulating of oxygen vacancies and designing of mesoporous structure syn-ergistically induced the excellent gas sensing performance. Therefore, this work can offer a promising strategy to enhance acetone sensing response of Fe2O3-Co3O4 in practical applications.
期刊：
Virtual and Physical Prototyping,2024年19(1) ISSN：1745-2759
通讯作者：
Bai, XW
作者机构：
[Bai, Xingwang; Xi, Shengxuan; Dong, Honghui; Liu, Mengru] Univ South China, Sch Mech Engn, Hengyang, Peoples R China.;[Li, Runsheng] China Univ Petr East China, Coll Mech & Elect Engn, Qingdao, Peoples R China.;[Zhang, Haiou] Huazhong Univ Sci & Technol, Sch Mech Sci & Engn, Wuhan, Peoples R China.;[Zhou, Xiangman] China Three Gorges Univ, Coll Mech & Power Engn China, Yichang, Peoples R China.
通讯机构：
[Bai, XW ] U;Univ South China, Sch Mech Engn, Hengyang, Peoples R China.
关键词：
Wire and arc additive manufacturing;3D point cloud;defect detection;surface curvature
摘要：
Wire and Arc Additive Manufacturing (WAAM) with high efficiency and low-cost is an economical choice for the rapid fabrication of medium-to-large-sized metallic components and has attracted great attention from scholars and entrepreneurs in recent years. However, defects such as porosity, and humps, could occur occasionally after each layer of deposition on weld bead surfaces due to disturbances and process abnormities. Detection and quantitative evaluation of weld bead defects is crucial to ensure successful deposition and the quality of the entire component. In this paper, a novel defect detection and evaluation system was developed for WAAM utilizing machine vision technology. The system incorporated new defect detection algorithms based on analysing the 2D curvature of the weld bead height curve and the 3D curvature of the weld bead point cloud. Furthermore, a defect evaluation algorithm was developed based on reconstructing the normal weld bead contour using geometric features extracted from the accumulated point cloud. This system enables the automatic detection of weld bead morphology during the WAAM process, offering important information about the location, type, and volume of defects for effective interlayer repairs and enhanced part quality.
期刊：
International Journal of Heat and Mass Transfer,2024年218 ISSN：0017-9310
通讯作者：
Zhou, XM
作者机构：
[Fu, Junjian; Tian, Qihua; Zhou, Xiangman; Zhou, Xing; Fu, Zichuan] China Three Gorges Univ, Coll Mech & Power Engn, Yichang 443002, Peoples R China.;[Zhou, Xing] China Three Gorges Univ, Hubei Key Lab Hydroelect Machinery Design & Mainte, Yichang 443002, Peoples R China.;[Bai, Xingwang] Univ South China, Sch Mech Engn, Hengyang 421001, Peoples R China.;[Zhang, Haiou] Huazhong Univ Sci & Technol, State Key Lab Digital Mfg Equipment & Technol, Wuhan 430074, Peoples R China.
通讯机构：
[Zhou, XM ] C;China Three Gorges Univ, Coll Mech & Power Engn, Yichang 443002, Peoples R China.
关键词：
WAAM;External deflection magnetic field;Heat and mass transfer;Numerical simulation;Overlapping flatness
摘要：
During the magnetic controlling wire arc additive manufacturing (WAAM) process, the external magnetic field directly influences the arc shape and the molten pool flow, which can further affect the morphology of the deposition layer and the overlapping flatness. This study introduced an external deflection magnetic field (EDM) with longitudinal and deposition direction components into the WAAM process. A numerical simulation model of the coupling of the arc and the molten pool was established on the basis of a weak coupling method. The numerical simulation model was utilized to investigate the effect of the EDM field on the heat and mass transfer behaviors in the WAAM overlapping deposition process. The results showed that the EDM field generated an additional electromagnetic force in the welding arc and molten pool with circumferential and single-side lateral components. The additional electromagnetic force drove the arc plasma to the rear of the molten pool and the side of the solidified weld bead simultaneously, which resulted in more heat and electromagnetic force concentrated on the gap of the overlapping beads. An asymmetric circumferential rotating vortex appeared in the molten pool, which drove the melted metal to fill the gap of the overlapping beads and improved the overlapping flatness.
关键词：
Al2O3–ZrO2;Crack propagation;Cracks;Laser powder bed fusion;Microstructure
摘要：
Abstract The cracks in Al2O3–ZrO2 eutectic ceramics produced by laser powder bed fusion (LPBF) have a significant impact on their practical applications in various industries. In order to understand the factors influencing crack formation, a systematic study of the characterization and propagation of cracks in single‐track, multi‐track, and bulk samples by varying the process parameters has been carried out in this research. The results showed that parallel cracks can be healed by reducing the scanning spacing and scanning length. Additionally, it was found that using a modest scanning speed and a shorter length can minimize the accumulation of thermal stress, resulting in the suppress crack formation. Based on this conclusion, a crack‐free Al2O3–ZrO2 eutectic ceramic sample was finally obtained under the optimized parameters with the power of 100 W, the scanning speed of 100 mm/s, the hatch spacing of 100 μm, the scanning length of 3 mm, and the layer thickness of 50 μm. Additionally, three typical microstructures, including eutectic, cellular, and dendritic structures, were identified in the LPBF‐fabricated Al2O3–ZrO2 samples. The cellular microstructure showed improved crack inhibition capability due to the deflection and pinning effects. Cracks expand more easily in dendritic and eutectic microstructures, where anisotropy is more prominent.
摘要：
The cutting vibration generated by cutting forces is critical to the accuracy and efficiency of face-hobbed hypoid gears. However, few relevant works are currently on cutting dynamics modeling for the face-hobbing process due to its complex spatial relationships. This study developed an efficient cutting dynamics model considering comprehensive characteristics of the non-generated face-hobbed hypoid gear machining process. A concise and efficient analytical solution to cutting dynamics modeling for face-hobbing of hypoid gears is obtained by using a vectorization method to characterize chip regenerating mechanisms. The machine tool vibration caused by cutting forces is predicted and validated according to an industrial case study. The proposed cutting dynamic model is 36.11% more efficient than the semi-analytical dynamic model derived from other cutting force prediction methods, and its accuracy is also improved with an error of less than 15%. Furthermore, the proposed vectorization solution to face-hobbing cutting dynamics modeling will be a practicable and effective method for analyzing the chatter in the machining of complex surfaces.
摘要：
The long-lived fission products (LLFPs) are one of the major impediments to the development of nuclear energy due to their longevity and toxicity. The fast neutron reactor, with its high neutron flux and excessed neutron, is a strong candidate for transmuting LLFPs. In this investigation, 79Se, 99Tc and 129I were selected as the representative nuclide of LLFPs, and then neutron moderators were loaded into the LLFPs assembly with LLFPs to evaluate the effect of different loading approaches on transmutation efficiency by the transmutation performance of LLFPs. The results show that the optimal loading strategy of moderator could increase the TR and SR with 2.35 (1.01) and 284.80 (151.11), 0.36 (0.28) and 8.06 (7.88), 1.69 (0.69) and 11.45 (7.80), respectively. It is suggested that it can transmute an additional 4500 g, 1000 g and 6600 g of these three LLFPs per year.
通讯机构：
[Feng, K ] H;Hunan Univ, State Key Lab Adv Design & Mfg Vehicle Body, Changsha 410082, Peoples R China.
关键词：
gas foil bearing;shape memory alloy;THD analysis;thermal energy transport;thermoelastohydrodynamic lubrication
摘要：
Shape memory alloy (SMA)-gas foil bearings (SMA-GFBs) are novel gas bearings comprising top foil, SMA springs, and housing. The radial clearance, stiffness, and damping coefficients of SMA-GFBs can be regulated by the bearing temperature which is determined by the electric heating of SMA springs and the cooling flow. A 3D thermohydrodynamic model (THD) considering the conduction and convection of the top foil, bearing housing, and hollow rotor, and the heat energy of heated SMA springs is presented to simulate the temperature distribution of SMA-GFBs at different rotational speeds, heating powers, and cooling flows. Centrifugal growth of the rotor and thermal expansions of the rotor, SMA springs, and bearing housing are also considered. A test rig is built to measure the bearing temperature and to validate the effectiveness of the theoretical model and circumferential cooling mode. Parametric studies are conducted with different speeds, heating powers, and cooling flows. The heat transfer ratios of the rotor and substructure are also compared. Compared to the temperature differences of the bearing temperature in the circumferential or axial directions, the effects of rotational speed and cooling flow on the bearing temperature are more apparent. The phase transition process of SMA spring can be controlled by adjusting the rotor speed and the cooling flow reasonably, and then the temperature characteristics of SMA-GFB can be changed. The temperature depending on the compressed gas film and heated SMA springs and cooling flow can be adjusted to confirm the feasibility of actively altering the performance of the bearing-rotor system.
作者机构：
[Li, ZY; Li, Zhenye; Huang, Chenhui; Li, Yuehao; Zhang, Meng; Ding, Xu] Univ South China, Coll Mech Engn, Hengyang 421001, Peoples R China.;[Ding, Yu-Feng] Univ South China, Sch Math & Phys, Hengyang 421001, Peoples R China.;[Zhu, Chunguang] Sichuan Univ Sci & Engn, Sch Mat Sci & Engn, Zigong 643002, Sichuan, Peoples R China.
通讯机构：
[Li, ZY ] U;Univ South China, Coll Mech Engn, Hengyang 421001, Peoples R China.
关键词：
cathode interface layer;non-covalent interaction;organic solar cells;power conversion efficiency;vermiculite
摘要：
Interface modification plays an important role in improving the power conversion efficiency (PCE) of organic solar cells (OSCs). However, the low non-covalent interaction between the cathode interface layer (CIL) and nonfullerene acceptor (NFA) directly affects the charge collection of OSCs. Here, the non-covalent interaction between the CIL and NFA is enhanced by introducing the 2D vermiculite (VML) in the poly(9,9-bis(3 '-(N,N-dimethyl)-Nethylammonium-propyl-2,7-fluorene)-alt-2,7-(9,9-dioctylfluorene)) dibromide (PFN-Br) interface layer to form an efficient electron transport channel. As a result, the electron extraction efficiency from the active layer to the CIL is increased, and the PCE of OSCs based on PBDB-T:ITIC is boosted from 10.87% to 12.89%. In addition, the strategy of CIL doping VML is proven to be universal in different CIL materials, for which the PCE is boosted from 10.21% to 11.57% for OSCs based on PDINN and from 9.82% to 11.27% for OSCs based on PNDIT-F3N. The results provide a viable option for designing efficient CIL for high-performance non-fullerene OSCs, which may promote the commercialization of OSCs. The non-covalent interaction between the cathode interface layer and nonfullerene acceptor is enhanced by introducing vermiculite in the PFN-Br interlayer. As a result, the power conversion efficiency of organic solar cells based on PBDB-T:ITIC is boosted from 10.87% to 12.89%. image
摘要：
The inevitable organic matters in radioactive wastewater and contaminated waters pose great challenge in uranium recycling by traditional techniques. Here, a self-driven solar coupling system (SSCS), which was assembled by a TiO(2) @MXene/CF cathode and a monolithic photoanode, was proposed for synergistically recycling uranium and degrading organics from complex radioactive wastewater, combining with electricity production. The TiO(2) @MXene/CF was prepared via a simple annealing process with in-situ derived TiO(2) nanoparticles decorated Ti(3)C(2) MXene coated on carbon felt (CF). Under sunlight illumination, the photoanode captured electrons of organics, and drove electrons to the TiO(2) @MXene/CF, which exhibited an exceptional UO(2)(2+) adsorption and reduction capacity because TiO(2) nanoparticles provided plenty of surface hydroxyl groups for UO(2)(2+) adsorption, and the unique two-dimensional MXene facilitated the charge transfer. The SSCS with TiO(2) @MXene/CF removed almost 100% UO(2)(2+) and organics with rate constants of ∼21 and ∼6.9 times those of the system with CF, accompanying with excellent power output (∼1000 μW·cm(-2)). The fixed uranium on TiO(2) @MXene/CF was effectively reduced into insoluble UO(2) (91.1%), and no obvious decay was observed after 15 repeated uses. This study proposes a multi-functional and easy-operated way for remediating radioactive wastewater and contaminated waters, and gives valuable insights in designing cathode materials for uranium reduction.
摘要：
Molecular dynamics (MD) simulation toward the irradiation cascade collision of GaN (10−10) by using different primary knock-on atom (PKA) energies was performed. Simulation results showed that point defects comprising vacancies and interstitials in pairs increased with increased PKA energy. The number of stable defects after cascade collision was linearly related to the PKA energy, which well agreed with the Norgett–Robinson–Torrens equation. Then, we investigated the effect of irradiation-induced point defects on the nanotribological properties and subsurface damage of the GaN (10−10) workpiece by MD simulation of nanoscratching. The irradiation-induced point defects induced a significant change in the wear morphology, as well as more slight wear and a lower coefficient of friction, compared with non-irradiated GaN. The irradiated GaN also exhibited fewer chips and smoother surfaces than the non-irradiated one after scratching. The number of deformed atoms of GaN increased with increased PKA energy, suggesting that irradiation can suppress the atomic/near-atomic scale deformation of GaN crystal under certain conditions. The presence of point defects can, to some extent, hinder the development of dislocations and differentiate the scratching-induced subsurface damage. This study provided atomic-scale insight into the effect of irradiation point defects on the nanotribological behavior of GaN.
通讯机构：
[Zeng, QY ; Yu, T] U;Univ South China, Sch Nucl Sci & Technol, Hengyang 421001, Hunan, Peoples R China.
关键词：
Uranium reduction;Uranyl-organic complex;Organic degradation;Electricity;Resourcization;Solar energy
摘要：
Co-existed organics bring great challenges for uranium recycling from water because of the formation of obstinate complexes with uranyl ions (UO22+), predominated species of uranium in water). Here, we proposed an effective strategy to simultaneously decompose organics and recycle uranium from complex radioactive waste-water, combined with electricity production, by a solar-driven wastewater resourcization system (SWRS), in which an electrodeposited polyaniline (PANI) decorated carbon fiber (CF-PANI) cathode was used for highly efficient UO22+ reduction based on the abundant -NH-groups and conductivity of PANI. Under sunlight illu-mination, a BiVO4 decorated WO3 nanoplate array (BVO/WNP) combined with a rear silicon cell (SC) was applied as the monolithic photoanode to generate oxidative holes and derived hydroxyl radicals for robust organic oxidation, and driven electrons to the CF-PANI cathode for uranium reduction and simultaneous elec-tricity generation at external circuit. Compared to CF, the optimized CF-PANI improved the rate constants (k) by 6 and 6.7 times for UO22+ and organic removal, respectively, and enhanced power output by 2 times (Pmax, 1.12 mW/cm2). Additionally, near 100 % removal ratios for both UO22+ and organics accompanying with Pmax around 1 mW/cm2 were achieved by SWRS when treating model complex wastewater under wide conditions or even under real sunlight illumination. The fixed uranium on the CF-PANI cathode was mainly reduced into U(IV) species (95.8 %) and the repeated tests demonstrated the excellent stability of SWRS (without obvious decay after reusing 15 times). This work provides new insights on the resourceful treatment of radioactive wastewater and contaminated waters.
