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Nuclear Science and Techniques 2022年第12期33卷 147-158页

作者： Gao‑Feng Wei Xin huang Qi‑jun Zhi Ai‑jun Dong Chang‑Gen Peng Zheng‑wen Long School of Physics and Electronic Science Guizhou Normal UniversityGuiyang 550025China Guizhou Provincial Key Laboratory of Radio Astronomy and Data Processing Guizhou Normal UniversityGuiyang 550025China Guizhou Provincial Key Laboratory of Public Big Data Guizhou UniversityGuiyang 550025China College of Physics Guizhou UniversityGuiyang 550025China

Within a transport model,we investigated the effects of the momentum dependence of the nuclear symmetry potential on the pion observables in central Sn+Sn collisions at 270 MeV/*** this end,the quantity U^(∞)_(sym)(ρ_(0))(i.e.,the value of the nuclear symmetry potential at the saturation densityρ_(0) and infinitely large nucleon momentum)was used to characterize the momentum dependence of the nuclear symmetry *** a certain L(i.e.,the slope of the nuclear symmetry energy at(ρ_(0))),the characteristic parameter U^(∞)_(sym)(ρ_(0))of the symmetry potential significantly affects the production of−and+and their pion ***,by comparing the charged pion yields,pion ratios,and spectral pion ratios of the theoretical simulations for the reactions ^(108) Sn+^(112) Sn and ^(132)Sn+^(124)Sn with the corresponding data in the SRIT experiments,we found that our results favor a constraint on U^(∞)_(sym)(ρ_(0))(i.e.,−160_(−9)^(+18) MeV),and L is also suggested within a range of 62.7 MeV

关键词： Nuclear symmetry potential Momentum dependence Symmetry energy

Incremental Multi-Label Learning with Active Queries

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Journal of Computer Science & Technology 2020年第2期35卷 234-246页

作者： Sheng-jun huang Guo-Xiang Li wen-Yu huang Shao-Yuan Li College of Computer Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing 211106China Key Laboratory of Pattern Analysis and Machine Intelligence Ministry of Industry and Information Technology Nanjing University of Aeronautics and AstronauticsNanjing 211106China Collaborative Innovation Center of Novel Software Technology and Industrialization Nanjing University Nanjing 210023China

In multi-label learning,it is rather expensive to label instances since they are simultaneously associated with multiple ***,active learning,which reduces the labeling cost by actively querying the labels of the most valuable data,becomes particularly important for multi-label learning.A good multi-label active learning algorithm usually consists of two crucial elements:a reasonable criterion to evaluate the gain of querying the label for an instance,and an effective classification model,based on whose prediction the criterion can be accurately *** this paper,we first introduce an effective multi-label classification model by combining label ranking with threshold learning,which is incrementally trained to avoid retraining from scratch after every *** on this model,we then propose to exploit both uncertainty and diversity in the instance space as well as the label space,and actively query the instance-label pairs which can improve the classification model *** experiments on 20 datasets demonstrate the superiority of the proposed approach to state-of-the-art methods.

关键词： active learning multi-label learning uncertainty diversity

Structural engineering of high-entropy alloys for advanced electrocatalytic reactions

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Tungsten 2025年第1期 1-31页

作者： Qiao Xie Ying-Jie Yu Hai-jun Zhang Ya-Ping Deng wen Lei The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and Technology Department of Chemical Engineering Waterloo Institute for Sustainable Energy Waterloo Institute for Nanotechnology University of Waterloo

High-entropy alloys(HEAs) have emerged as promising candidates to replace traditional precious metal catalysts,owing to their unique chemical and physical *** review commences by revisiting the fundamental concepts of HEAs,including their synthesis methods and structural control strategies in *** underscores the critical role of meticulously manipulating both macroscopic and microscopic structures of the HEAs to optimize their catalytic performance.A deep understanding of the structure-activity relationship in HEAs across various configurations is pivotal in developing more effective *** review methodically encapsulates the research progress of structural control strategies for HEAs in achieving efficient energy conversion,with the aim of gaining a better understanding of the relationship between structure and *** review concludes by summarizing the current achievements and challenges,and suggestions for potential future directions of HEAs in the fields of energy conversion and environmental purification.

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不同宿主来源产气荚膜梭菌生物被膜形成前后药物敏感性分析

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动物医学进展 2025年第1期46卷 38-42页

作者：吴莹邵长军刘文华青岛农业大学动物医学院山东青岛266109 烟台市农科院山东烟台264200

为了检测5株不同宿主来源产气荚膜梭菌形成生物被膜能力及其对抗菌药物的敏感性差异,首先用纸片扩散法药敏试验测定5株不同来源的产气荚膜梭菌对7种抗菌药物的敏感性;筛选高敏药物测定各菌株的最小抑菌浓度(MIC);利用结晶紫染色法检测... 详细信息

为了检测5株不同宿主来源产气荚膜梭菌形成生物被膜能力及其对抗菌药物的敏感性差异,首先用纸片扩散法药敏试验测定5株不同来源的产气荚膜梭菌对7种抗菌药物的敏感性;筛选高敏药物测定各菌株的最小抑菌浓度(MIC);利用结晶紫染色法检测不同来源产气荚膜梭菌生物被膜形成能力和高敏药物对生物被膜的抑制和清除能力。药敏结果显示,5株不同宿主来源产气荚膜梭菌均对氨苄西林高度敏感,对其余6种抗菌药物有不同程度耐药;氨苄西林对不同菌株的MIC值在0.031~2.000μg/mL之间;所有菌株均能生成生物被膜,但生物被膜生成能力有差异;不同菌株在各自4、2、1 MIC下生物被膜的生成受到不同程度抑制,而亚抑菌浓度的氨苄西林能刺激生物被膜的生成,氨苄西林对已经生成的生物被膜不能完全清除。结果表明,不同来源产气荚膜梭菌形成生物被膜前后对药物敏感性不同,可为产气荚膜梭菌的临床用药选择及使用剂量提供一定的参考依据。

关键词：产气荚膜梭菌生物被膜最小抑菌浓度耐药性

Microstructure and high-temperature wear properties of in situ TiC composite coatings by plasma transferred arc surface alloying on gray cast iron

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International Journal of Minerals,Metallurgy and Materials 2015年第12期22卷 1273-1282页

作者： Hang Zhao Jian-jun Li Zhi-zhen Zheng Ai-hua Wang Qi-wen huang Da-wen Zeng State Key Laboratory of Material Processing and Die & Mould Technology Huazhong University of Science & Technology

In this work, an in situ synthesized TiC-reinforced metal matrix composite （MMC） coating of approximately 350-400μm thickness was fabricated on a gray cast iron （GCI） substrate by plasma transferred arc （PTA） surface alloying of Ti-Fe alloy powder. Microhard- ness tests showed that the surface hardness increased approximately four-fold after the alloying treatment. The microstructure of the MMC coating was mainly composed of residual austenite, acicular martensite, and eutectic ledeburite. Scanning electron microscopy （SEM） and X-ray diffraction analyzes revealed that the in situ TiC particles, which were formed by direct reaction of Ti with carbon originally contained in the GCI, was uniformly distributed at the boundary of residual anstenite in the alloying zone. Pin-on-disc high-temperature wear tests were performed on samples both with and without the MMC coating at room temperature and at elevated temperatures （473 K and 623 K）, and the wear behavior and mechanism were investigated. The results showed that, after the PTA alloying treatment, the wear resistance of the sam- ples improved significantly. On the basis of our analysis of the composite coatings by optical microscopy, SEM with energy-dispersive X-ray spectroscopy, and microhardness measurements, we attributed this improvement of wear resistance to the transformation of the microstruc- ture and to the presence of TiC particles.

关键词： gray cast iron composite coatings particle-reinforced composites titanium carbide surface alloying microstructure wear

Influences of Hot-Isostatic-Pressing Temperature on the Microstructure, Tensile Properties and Tensile Fracture Mode of 2A12 Powder Compact

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Acta Metallurgica Sinica(English Letters) 2016年第10期29卷 963-974页

作者： Gang Wang Li-Hui Lang wen-jun Yu Xi-Na huang Fei Li School of Mechanical Engineering and Automation Beihang University Beijing 100191 China Avic Chengdu Aircraft Industrial (Group) Co. Ltd Chengdu 610000 China

2A12 aluminum alloy powders were hot-isostatic-pressed （HIPed） at representative temperatures for investi- gating the variation in microstructure, tensile property and fracture mode of the powder compact. It was found that the microstructure of raw powders changed from a dendrite structure to an equiaxed structure from room temperature to 600 ℃. The liquid phase produced by the eutectic reaction in the powder was gradually increased and finally formed a liquid pathway that ran through the entire powder from 490 to 600℃. Prior particle boundaries were observed in the powder compacts HIPed at 490 and 520℃. The liquid phase in the powder compacts was squeezed into the powder boundaries and the triple points of powder when HIPed at 580℃. However, the liquid phase located at the triple points of the powder was forced out and moved toward a small powder particle by HIP pressure under an HIPing temperature of 600℃, which led to a decrease in the mechanical properties and relative density. Better comprehensive properties were obtained at HIPing temperatures of 490 and 580℃. The low ductility exhibited by the P/M aluminum alloy HIPed at different temperatures was believed to arise from a combination of the existence of oxide film on the powder particle surface and the distribution characteristics of the liquid phase. Finally, three typical types of de-cohesion were classified.

关键词： Powder metallurgy Hot-isostatic-pressing Microstructural evolution Fracture mode Aluminum alloy Mechanical properties

Synthesis and Biological Activity of New Pyrethroid Acid Oxime-esters Containing Pyrazole Ring

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Chemical Research in Chinese Universities 2003年第3期19卷 297-301页

作者： MA jun-an huang Run-qiu FENG Lei SONG Jian QIU De-wen Institute and State Key Laboratory of Elemento-organic Chemistry Nankai UniversityTianjin 300071P.R.China

A series of compounds containing oxime-ester linkage and pyrazole ring(in place of the ester linkage and the alcohol moiety in pyrethroid ester) was designed and synthesized. The structures of all the compounds prepared were confirmed by 1H NMR and MS spectroscopy as well as elemental analyses. The bioassay data of those compounds against tobacco mosaic virus(TMV), cucumber mosaic virus(CMV), potato virus X(PVX) and potato virus Y(PVY) were presented. Among them compound 6i was found to possess significant plant antiviral activities. But all the compounds showed low insecticidal and acaricidal activities.

关键词： Pyrethroid Oxime-ester Synthesis Pyrazole Plant antiviral activity

Electrically pumped terahertz laser based on a topological insulator quantum dot array

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Science China(Physics,Mechanics & Astronomy) 2021年第1期64卷 82-90页

作者： YongWei huang LiKun Shi jun Li wenKai Lou HuiHong Yuan wen Yang Kai Chang State Key Laboratory for Superlattices and Microstructures Institute of SemiconductorsChinese Academy of SciencesBeijing100083China CAS Center for Excellence in Topological Quantum Computation University of Chinese Academy of SciencesBeijing100190China Department of Physics Semiconductor Photonics Research CenterXiamen UniversityXiamen361005China Beijing Academy of Quantum Information Sciences Beijing100193China Beijing Computational Science Research Center Beijing100193China

The energy level separation between the edge states in topological insulator quantum dots lies in the terahertz(THz) *** confinement ensures the nonuniformity of the energy level separation near the Dirac point. Based on these features, we propose that a topological insulator quantum dot array can be operated as an electrically pumped continuous-wave THz laser. The proposed device can operate at room temperature, with power exceeding 10 mW and quantum efficiency reaching ~50%. This study may promote the usage of topological insulator quantum dots as an important source of THz radiation.

关键词： terahertz topological insulator quantum dot and quantum confinement effect

[Solid-phase extraction coupled with high performance liquid chromatography-triple quadrupole mass spectrometry for simultaneous determination of seven coumarins in water samples from drinking water treatment plants]

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Se pu = Chinese journal of chromatography 2025年第1期43卷 78-86页

作者： wen-Mei Jiao Jing-Ming Yang Ce Xu Fu-Kang Gao Lu-Yao Shen Yu-Bo Yuan Zhi-Fen Guo Guang huang School of Life Sciences and Chemical Engineering Jiangsu Second Normal University Nanjing 211200 China. School of Stomatology Nanjing Medical University Nanjing 210029 China. School of Public Health Nanjing Medical University Nanjing 211166 China. Key Laboratory of Modern Toxicology Ministry of Education School of Public Health Nanjing Medical University Nanjing 211166 China.

Chlorinated coumarins, which are as cytotoxic as highly toxic halobenzoquinones toward CHO-K1 cells, have recently been identified as disinfection byproducts in drinking water disinfection processes. Therefore, detecting coumarins in water samples collected at various stages from drinking water treatment plants helps assess the formation of chlorinated coumarins in drinking water. Hence, a simple, rapid, accurate, and sensitive method for quantifying coumarins in water samples is required. In this study, a method was developed based on solid-phase extraction coupled with high performance liquid chromatography-triple-quadrupole mass spectrometry for analyzing seven coumarins in water samples from drinking water treatment plants, including 6,7-dihydroxycoumarin, 7-hydroxycoumarin, 6-hydroxy-4-methylcoumarin, 8-chloro-7-hydroxycoumarin, coumarin, 7-chloro-6-hydroxy-4-methylcoumarin, and 3,8-dichloro-7-hydroxycoumarin. Sample pretreatment involved solid-phase extraction using HLB columns, followed by elution with water and methanol, each containing 0.25% formic acid. The extracted solution was separated via gradient elution using a Phenomenex Luna C18 column (100 mm×2.0 mm, 3 mm) with 0.1% formic acid aqueous solution and methanol as the mobile phases, with analytes detected by triple-quadrupole mass spectrometry equipped with electrospray ionization source in multiple reaction monitoring mode. The matrix effect, precision, and accuracy of the developed method were investigated using raw and treated water as matrices. Matrix effects of 0.84-1.12 were recorded for the detection of 6,7-dihydroxycoumarin, 7-hydroxycoumarin, 6-hydroxy-4-methylcoumarin, and coumarin in raw water, while values of 0.67-0.70 were recorded for 8-chloro-7-hydroxycoumarin, 7-chloro-6-hydroxy-4-methylcoumarin, and 3,8-dichloro-7-hydroxycoumarin in finished water. The three chlorinated coumarins exhibited matrix effects above 0.80 after the finished water matrix had been diluted four times. These re

关键词： coumarins disinfection byproducts drinking water high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) solid-phase extraction (SPE)

Thermal and Mechanical Properties of Graphene-Titanium Composites Synthesized by Microwave Sintering

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Acta Metallurgica Sinica(English Letters) 2016年第8期29卷 707-713页

作者： wen-Zhi Yang Wei-Ming huang Zhi-Feng Wang Fu-jun Shang Wei huang Bao-Yu Zhang Ningbo Branch of China Academy of Ordnance Science College of Mechanical Engineering and Mechanics Ningbo University

The x wt%graphene-Ti composites（x = 0,0.2,0.3 and 0.4） were obtained using the powder metallurgy *** X-ray diffraction results demonstrated that the peak intensity of graphene increased monotonically with increasing graphene ***,the number of grain boundary and interface between graphene and matrix increased as graphene increased,which led to a sharp rise of thermal *** thermal conductivity and specific heat capacity of composites initially decreased drastically with addition of graphene,but then increased with increasing graphene content from 0.2 to 0.4 wt%.This phenomenon was connected with the graphene content and the characteristics of Ti matrix（pores,grain boundary and interface between graphene and matrix）.The variation of the compressive strength of composites was attributed to the interaction effects of the average grain size of the Ti matrix（d_m） and the volume fraction（V_f） and aspect ratio（A） of graphene.

关键词： Graphene Metal-matrix composites Thermal properties Compressive strength