期刊：
Chemical Engineering Journal,2024年485:149856 ISSN：1385-8947
通讯作者：
Yi-Lin Liu<&wdkj&>Qingyi Zeng
作者机构：
[Chao Zhang; Yi-Lin Liu; Qingming Zeng; Yanjun Wen; Lulin Guo; Haodong Chen; Xinyi Xie; Qingyi Zeng] School of Mechanical Engineering, & School of Resources & Environment and Safety Engineering, University of South China, Hengyang 421001, PR China;[Yi Wang] Laboratory of Environmental Technology, INET, Tsinghua University, Beijing 100084, China
通讯机构：
[Yi-Lin Liu; Qingyi Zeng] S;School of Mechanical Engineering, & School of Resources & Environment and Safety Engineering, University of South China, Hengyang 421001, PR China
摘要：
An innovative MnO/Ti3C2 MXene heterostructure, consisting of three-dimensional (3D) MnO nanosheet array directly assembled on two-dimensional (2D) Ti3C2 MXene nanosheets, was synthesized via a simple hydrothermal-annealing strategy for uranium elimination. This unique 3D/2D heterostructure derived substantially high specific surface area (311.9 m2/g) and exposed considerable amount of surface oxygen groups, including surface lattice M–O and adsorbed –OH. Through a comprehensive exploration encompassing adsorbent dosage, pH, ionic strength, initial U(VI) concentration, and environmental conditions, the MnO/Ti3C2 MXene heterostructure demonstrated an extraordinary proficiency and specificity in the removal of U(VI). This composite exhibited an outstanding adsorption capacity of 862.1 mg/g, with a removal efficiency of 99.7 % and rapid kinetics (above 90 % within 20 s). The kinetic study indicated the adsorption process followed chemisorption dynamics and single-layer adsorption behavior. Comprehensive analyses validated the structural integrity and confirmed the successful uranium adsorption via strong interaction between UO22+ and surface unsaturated oxygen groups. Notably, the MnO/Ti3C2 MXene maintained excellent recyclability, highlighting its potential for large-scale applications. It emerges as a promising candidate for uranium removal, offering insights for optimizing composite materials in diverse environmental conditions and fostering advancements in water purification technologies.
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.
期刊：
CALPHAD-COMPUTER COUPLING OF PHASE DIAGRAMS AND THERMOCHEMISTRY,2024年84:102666 ISSN：0364-5916
通讯作者：
Huixin Liu<&wdkj&>Shiyi Wen
作者机构：
[Hui Yang; Shipeng Huang; Xiangyang Yin; Peiqiong Zhou; Qianhui Min; Yuling Liu; Yong Du] State Key Laboratory of Powder Metallurgy, Central South University, Changsha, Hunan, 410083, China;[Huixin Liu] School of Energy and Mechanical Engineering, Hunan University of Humanities, Science and Technology, Loudi, Hunan, 417000, China;School of Metallurgy and Environment, Central South University, Changsha, Hunan, 410083, China;[Changfa Du] School of Mathematics and Statistics, Changsha University of Science and Technology, Changsha, Hunan, 410114, China;School of Mechanical Engineering, University of South China, Hengyang, Hunan, 421001, China
通讯机构：
[Huixin Liu; Shiyi Wen] S;School of Energy and Mechanical Engineering, Hunan University of Humanities, Science and Technology, Loudi, Hunan, 417000, China<&wdkj&>State Key Laboratory of Powder Metallurgy, Central South University, Changsha, Hunan, 410083, China<&wdkj&>School of Metallurgy and Environment, Central South University, Changsha, Hunan, 410083, China
摘要：
Diffusion study of the Ni–Si–V system is significant for the establishment of kinetic database of Ni-based alloys. In this work, the diffusion couple experiment combined with the numerical inverse method was adopted to evaluate the diffusivities and atomic mobilities for the Ni–Si–V fcc phase with high throughput. We prepared 12 fcc Ni–Si–V diffusion couples, which were annealed at 1273, 1373 and 1473 K, and their composition profiles after annealing were then measured by EPMA (Electron Probe Microanalysis). Subsequently, inputting the measured composition profiles as well as the available thermodynamic descriptions into the numerical inverse method incorporated in the CALTPP (CALculation of ThermoPhysical Properties) software, the composition- and temperature-dependent diffusivities and atomic mobilities for the Ni–Si–V fcc phase were simultaneously evaluated. In order to verify the reliability of the present evaluations, the CALTPP-simulated diffusion behaviors such as composition profiles and diffusion paths were compared with the measured ones, demonstrating reasonable agreements with each other. Meanwhile, the high-throughput determinations of diffusivities were confirmed by the ones obtained by the Matano-Kirkaldy method. Furthermore, applying the presently obtained diffusivities and atomic mobilities in combination with thermodynamic descriptions of the Ni–Si–V fcc phase, their diffusion flux, two-dimensional composition profile, activation energy and pre-frequency factor were predicted. It is expected that the presently obtained diffusivities and atomic mobilities of the Ni–Si–V fcc phase can contribute to the establishment of kinetic database of Ni-based alloys for their high-efficiency material design.
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
期刊：
Nuclear Engineering and Technology,2024年 ISSN：1738-5733
通讯作者：
Changjun Qiu
作者机构：
School of Resource Environment and Safety Engineering, University of South China, Hengyang, Hunan, 421001, China;School of Mechanical Engineering, University of South China, Hengyang, Hunan, 421001, China;Key Laboratory of Emergency Safety Technology and Equipment of Nuclear Facilities in Hunan Province, Hengyang, Hunan, 421001, China;[Wen Chen; Jianyong Dai; Meirong Zhang] School of Resource Environment and Safety Engineering, University of South China, Hengyang, Hunan, 421001, China<&wdkj&>Key Laboratory of Emergency Safety Technology and Equipment of Nuclear Facilities in Hunan Province, Hengyang, Hunan, 421001, China;[Shuliang Zou; Changjun Qiu] School of Mechanical Engineering, University of South China, Hengyang, Hunan, 421001, China<&wdkj&>Key Laboratory of Emergency Safety Technology and Equipment of Nuclear Facilities in Hunan Province, Hengyang, Hunan, 421001, China
通讯机构：
[Changjun Qiu] S;School of Mechanical Engineering, University of South China, Hengyang, Hunan, 421001, China<&wdkj&>Key Laboratory of Emergency Safety Technology and Equipment of Nuclear Facilities in Hunan Province, Hengyang, Hunan, 421001, China
摘要：
Modern risk management philosophy emphasizes the invulnerability of human beings to cope with all kinds of emergencies. The Nuclear Accidents Emergency Response Organization (NAERO) of Nuclear Power Plant (NPP) is the primary body responsible for nuclear accidents emergency response. The invulnerability of the organization to disturbance or attack from internal and external sources is crucial in the completion of its response missions, reduction of severity of accidents, and assurance of public and environmental safety. This paper focused on the NAERO of a certain NPP in China, and applied the complex network theory to construct the network model of the organization. The topological characteristics of the network were analyzed. Four importance evaluation indexes of network nodes including Degree Centrality (DC), Betweeness Centrality (BC), Closeness Centrality (CC) and Eigenvector Centrality (EC), along with Pearson coefficient correlation among the indexes were calculated and analyzed. Size of the Largest Connected Component (LCC) and Network Efficiency were used as measures regarding the invulnerability of the network. Simulation experiments were conducted to assess the invulnerability of network against various attack strategies. These experiments were conducted both in the absence of node protection measures and under protection measures with different node protection rates. This study evaluated the invulnerability of the NAERO network, and provided significant decision-making basis for the enhancement of the network's invulnerability.
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.
期刊：
Journal of Materials Research and Technology,2024年29:1066-1075 ISSN：2238-7854
通讯作者：
Yinghao Zhou
作者机构：
[Pinghu Chen; Changjun Qiu; Wenxing Wu] College of Mechanical Engineering, Key Laboratory of Hunan Province of Equipment Safety Service Technology Under Extreme Environment, University of South China, 421001, Hengyang, China;[Ruiqing Li] Light Alloys Research Institute, State Key Laboratory of Precision Manufacturing for Extreme Service Performance, Central South University, 410083, Changsha, China;[Yun Zhang] School of Mechanical Engineering, Hunan University of Science and Technology, 411201, Xiangtan, China;[Ming Yan] Department of Materials Science and Engineering, Southern University of Science and Technology, 518055, Shenzhen, China;Department of Mechanical Engineering, City University of Hong Kong, Hong Kong, China
通讯机构：
[Yinghao Zhou] D;Department of Materials Science and Engineering, Southern University of Science and Technology, 518055, Shenzhen, China<&wdkj&>Department of Mechanical Engineering, City University of Hong Kong, Hong Kong, China
摘要：
Commercially pure titanium (CP–Ti) took advantages of low stiffness, high corrosion resistance and bio-compatibility, implying an ideal structural material in aerospace, military and medical industries. However, its insufficient mechanical properties have always been the long-standing obstacle for the industrial applications. In this work, we have achieved a superior strong and ductile CP-Ti via active atmosphere-assisted selective laser melting (SLM) and subsequent rolling treatment. By incorporating the active N2 atmosphere during SLM, mechanical properties of CP-Ti were substantially improved, microhardness of the lyaers with 10 at.% and 100 at.% was 63 % and 174.3 % higher than that of CP-Ti with 182.3 HV0.2, the compressive strength of 10 sample was 27.1 % higher than that of 10 L sample when the strain was 52.2 %, and ultimate tensile strength of 10 sample reached 928 MPa with an elongation of 25.6 %, and ultimate tensile strength and elongation of 10 L sample were enhanced simultaneously by 58.3 % and 13.6 % relative to CP-Ti sample. These were attributed to the interstitial strengthening induced by N atoms. After rolling treatment, the mechanical properties of N-doping layers could enhance furtherly. Macroscale cracking along the rolling direction never occur in the 10 L sample during the repeatedly rolling treatment, which could depend to high tolerability of sandwich layers for high-density dislocations. Meanwhile, rolling treatment played an important role for refining grain to enhance the strength further.
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：
Journal of Alloys and Compounds,2024年982:173679 ISSN：0925-8388
通讯作者：
Changjun Qiu
作者机构：
School of Mechanical Engineering, University of South China, Hengyang 421001, China;[Wenxing Wu; Hao Liu] Key Laboratory of Hunan Province of Equipment Safety Service Technology under Extreme Environment, Hengyang 421001, China;[Tong Yang; Li Zhao; Pinghu Chen; Changjun Qiu] School of Mechanical Engineering, University of South China, Hengyang 421001, China<&wdkj&>Key Laboratory of Hunan Province of Equipment Safety Service Technology under Extreme Environment, Hengyang 421001, China
通讯机构：
[Changjun Qiu] S;School of Mechanical Engineering, University of South China, Hengyang 421001, China<&wdkj&>Key Laboratory of Hunan Province of Equipment Safety Service Technology under Extreme Environment, Hengyang 421001, China
摘要：
The high cracking susceptibility is the major obstacle to the wide application of high γ′-phase nickel-based superalloys in additive manufacturing. It is especially important to explore the effects of alloying elements during the nickel-based superalloys and establish a new alloy design criterion. In this work, a new nickel-based superalloys with crack-free and low porosity was fabricated by adjusting the content of solid-solution and precipitating elements of Inconel 738LC (IN738LC) alloy utilizing laser directed energy deposition (LDED) technology, achieving an increase in strength and ductility simultaneously. The newly developed nickel-based superalloys maintain a high content of γ′-phase and display substantial fine bulk MC carbides, resulting in higher strength (UTS: 1461 MPa, YS: 1105 MPa) and elongation (EL: 12.9%). After heat treatment, extensive long-stripes of M23C6 carbides were detected in the IN738LC sample, which led to poor tensile properties at high temperature (900 °C). However, due to the finer γ′ phase uniformly distributed in the matrix, the developed new nickel-based superalloys exhibits optimal tensile properties (UTS: 593 MPa, YS: 475 MPa) and ductility (9.4%) at 900 °C. This approach can provide guidance for the design of high γ′-phase nickel-based superalloys for additive manufacturing starting from elemental powders.
期刊：
Progress in Organic Coatings,2024年189:108309 ISSN：0300-9440
通讯作者：
Yi-Lin Liu<&wdkj&>Zhenye Li
作者机构：
[Gaoyang Wang; Yi-Lin Liu; Zhenye Li] College of Mechanical Engineering, University of South China, Hengyang 421001, PR China
通讯机构：
[Yi-Lin Liu; Zhenye Li] C;College of Mechanical Engineering, University of South China, Hengyang 421001, PR China
摘要：
Poly(9,9-bis(3′-(N,N-dimethyl)-Nethylammonium-propyl-2,7-fluorene)-alt-2,7- (9,9-dioctylfluorene)) dibromide (PFN-Br) has been widely used as an cathode interface layer (CIL) for efficient organic solar cells (OSCs) because of its straightforward solution processability, excellent electron extraction ability, as well as prominent compatibility with various OSCs systems. However, the relatively low conductivity of PFN-Br results in CIL thicknesses usually <10 nm prepared from PFN-Br, which is obviously not conducive to the roll-to-roll large-scale production of OSCs. In this work, titanium carbide (Ti3C2) was doped into the conventional CIL-material PFN-Br to improve the conductivity of PFN-Br, increase the electron extraction of the active layer, as well as optimize the ohmic contact between the CIL and the electrode. As a result, the power conversion efficiency (PCE) was boosted from 14.56 % to 15.80 % for OSCs based on PTzBI-oF:PYF-T-o, from 15.49 % to 17.27 % for OSCs based on PM6:L8-BO and from 17.65 % to 19.12 % for OSCs based on D18:L8-BO. The application of Ti3C2 doping PFN-Br strategy is expected to bring new opportunities for improving the conductivity of high performance CIL, so as to boost the PCE and promote the commercialization of OSCs.
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.
作者：
Su, Chi;Hua, Yilong;Liu, Yi;Tao, Shu;Jia, Fei;...
期刊：
PLOS ONE,2024年19(3):e0300800 ISSN：1932-6203
作者机构：
[Hua, Yilong; Liu, Yi; Su, Chi; Zhao, Wenhui] School of Resources Environment and Safety Engineering, University of South China, Hengyang, China;[Tao, Shu] School of Mathematics and Physics, University of South China, Hengyang, China;[Jia, Fei] School of Civil Engineering, University of South China, Hengyang, China;[Zhao, Wenhui] Shanxi Province Changzhi City Wuxiang County Jia Huo Township People's Government, Changzhi, China;[Lin, Wangyang] College of Mechanical Engineering, University of South China, Hengyang, China
摘要：
Mining wastewater with heavy metals poses a serious threat to the ecological environment. However, the acute single and combined ecological effects of heavy metals, such as chromium (Cr) and nickel (Ni), on freshwater ostracods, and the development of relevant prediction models, remain poorly understood. In this study, Heterocypris sp. was chosen to investigate the single and combined acute toxicity of Cr and Ni. Then, the quantitative structure-activity relationship (QSAR) model was used to predict the combined toxicity of Cr and Ni. The single acute toxicity experiments revealed high toxicity for both Cr and Ni. In addition, Cr exhibited greater toxicity compared to Ni, as evidenced by its lower 96-hour half-lethal concentration (LC50) of 1.07 mg/L compared to 4.7 mg/L for Ni. Furthermore, the combined acute toxicity experiments showed that the toxicity of Cr-Ni was higher than Ni but lower than Cr. Compared with the concentration addition (CA) and independent action (IA) models, the predicted results of the QSAR model were more consistent with the experimental results for the Cr-Ni combined acute toxicity. So, the high accuracy of QSAR model identified its feasibility to predict the toxicity of heavy metal pollutants in mining wastewater.
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.
