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International Journal of Minerals,Metallurgy and Materials 2018年第9期25卷 1060-1069页

作者： Ping-hu Chen Yi-bo li Rui-qing li Ri-peng Jiang Song-sheng Zeng Xiao-qian li College of Mechanical and Electrical Engineering Central South UniversityChangsha 410083China State Key Laboratory of High Performance Complex Manufacturing Changsha 410083China light Alloy Research Institutes Central South UniversityChangsha 410083China Valin ArcelorMittal Automotive Steel Co. Ltd.Loudi 417000China

A quenching and partitioning(Q&P) process was applied to vanadium carbide particle(VCp)-reinforced Fe-matrix composites(VC-Fe-MCs) to obtain a multiphase microstructure comprising VC, V8 C7, M3 C, α-Fe, and γ-Fe. The effects of the austenitizing temperature and the quenching temperature on the microstructure, mechanical properties, and wear resistance of the VC-Fe-MCs were studied. The results show that the size of the carbide became coarse and that the shape of some particles began to transform from diffused graininess into a chrysanthemum-shaped structure with increasing austenitizing temperature. The microhardness decreased with increasing austenitizing temperature but substantially increased after wear testing compared with the microhardness before wear testing; the microhardness values improved by 20.0% ± 2.5%. Retained austenite enhanced the impact toughness and promoted the transformation-induced plasticity(TRIP) effect to improve wear resistance under certain load conditions.

关键词： vanadium carbide Fe-matrix composites quenching and partitioning process transformation-induced plasticity effect microhardness impact toughness wear resistance

Label Recovery and Trajectory Designable Network for Transfer Fault Diagnosis of Machines With Incorrect Annotation

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IEEE/CAA Journal of Automatica Sinica 2024年第4期11卷 932-945页

作者： Bin Yang Yaguo Lei Xiang li Naipeng li Asoke K.Nandi the Key Laboratory of Education Ministry for Modern Design and Rotor-Bearing System the School of Mechanical EngineeringXi’an Jiaotong UniveristyXi’an 710049 the Hunan Provincial Key Labortory of Health Maintenance for Mechanical Equipment Hunan Univeristy of Science and TechnologyXiangtan 411201China the Key Laboratory of Education Ministry for Modern Design and Rotor-Bearing System Xi’an Jiaotong UniveristyXi’an 710049China the Department of Electronic and Electrical Engineering Brunel University LondonUxbridge UB83PHUK

The success of deep transfer learning in fault diagnosis is attributed to the collection of high-quality labeled data from the source ***,in engineering scenarios,achieving such high-quality label annotation is difficult and *** incorrect label annotation produces two negative effects:1)the complex decision boundary of diagnosis models lowers the generalization performance on the target domain,and2)the distribution of target domain samples becomes misaligned with the false-labeled *** overcome these negative effects,this article proposes a solution called the label recovery and trajectory designable network(LRTDN).LRTDN consists of three ***,a residual network with dual classifiers is to learn features from cross-domain ***,an annotation check module is constructed to generate a label anomaly indicator that could modify the abnormal labels of false-labeled samples in the source *** the training of relabeled samples,the complexity of diagnosis model is reduced via semi-supervised ***,the adaptation trajectories are designed for sample distributions across *** ensures that the target domain samples are only adapted with the pure-labeled *** LRTDN is verified by two case studies,in which the diagnosis knowledge of bearings is transferred across different working conditions as well as different yet related *** results show that LRTDN offers a high diagnosis accuracy even in the presence of incorrect annotation.

关键词： Deep transfer learning domain adaptation incorrect label annotation intelligent fault diagnosis rotating machines

Semisolid-rolling and annealing process of woven carbon fibers reinforced Al-matrix composites

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Journal of Materials Science & Technology 2017年第7期33卷 623-629页

作者： Junjia Zhang Shichao liu Yiping Lu li Jiang Yubo Zhang Tingju li Key Laboratory of Solidification Control and Digital Preparation Technology （liaoning Province） School of Materials Science and Engineering Dalian University of Technology Dalian 116024 China

Semisolid-rolling method was successfully developed to prepare the Ni-coated woven carbon fibers reinforced Al-matrix composite. Due to the appropriate matrix flowability and rolling pressure, the Al-matrix could infiltrate into the woven fibers sufficiently and attach to the reinforcements closely forming a smooth interface. The rolling speed of 4 rad/min offered a subtle equilibrium between the heat transfer and the material deformation. The covering matrix should be controlled at semisolid state to provide a better infiltration behavior and a protective effect on the carbon fibers. With the addition of fibers, an improvement for more than 25% was obtained in the bending strength of the materials. Furthermore, the woven carbon fibers could strengthen the composite in multiple directions, rather than only along the fiber longitudinal directions. The annealing process promoted the Ni coating to react with and to diffuse into the matrix, resulted in an obvious increase of the bending strength.

关键词： Metal-matrix composites Woven carbon fiber Semisolid-rolling process Annealing Mechanical property

Low-temperature NH_(3)-SCR of NO_(x) over MnCeO_(x)/TiO_(2) catalyst:Enhanced activity and SO_(2) tolerance by modifying TiO_(2) with Al_(2)O_(3)

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Journal of Rare Earths 2021年第7期39卷 805-816,I0002页

作者： Gang li Dongsen Mao Mengxi Chao Gehua li Jun Yu Xiaoming Guo School of Chemical and Environmental Engineering Shanghai Institute of TechnologyShanghai 201418China

A series of TiO_(2)-Al_(2)O_(3) composites with Al/Ti molar ratios of 0.1,0.2,and 0.4 were synthesized by a coprecipitation method and used as supports to prepare supported MnCeO_(x) catalysts by an impregnation *** physico-chemical properties of the samples were extensively characterized by N_(2) physisorption,X-ray diffraction,Raman spectroscopy,scanning electron micro scopy and energy-dispersive Xray spectroscopy element mapping,X-ray photoelectron spectroscopy,H_(2)-temperature programmed reduction,ammonia temperature programmed desorption,and in-situ diffuse reflectance infrared Fourier transform *** catalytic activity and resistance to water vapor and SO_(2) of the asprepared catalysts for the SCR of NO_(x) with NH_(3) were evaluated at 50-250℃ and GHSV of 80000 mL/(gcat·h).The results reveal that MnCeO_(x)/TiO_(2)-Al_(2)O_(3) exhibits higher activity and better SO_(2) tolerance than MnCeO_(x)/TiO_(2).Combining with the characterization results,the enhanced activity and SO_(2) tolerance of MnCeO_(x)/TiO_(2)-Al_(2)O_(3) can be mainly attributed to higher relative concentrations of Mn4+and chemisorbed oxygen species,stronger reducibility,and larger adsorption capacity for NH_(3) and NO,which originate from the larger specific surface area and pore volume,higher dispersion of Mn and Ce species compared with MnCeO_(x)/TiO_(2).Moreover,in situ DRIFTS was used to investigate the reaction mechanism,and the results indicate that the NH_(3)-SCR reaction over MnCeO_(x)/TiO_(2) and MnCeO_(x)/TiO_(2)-Al_(2)O_(3) takes place by both the E-R and L-H mechanisms.

关键词： Low-temperature NH_(3)-SCR MnCeO_(x)/TiO_(2)catalyst TiO_(2)-Al_(2)O_(3)mixed oxide SO_(2)tolerance Rare earths

Noble-metal free plasmonic nanomaterials for enhanced photocatalytic applications—A review

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Nano Research 2022年第12期15卷 10268-10291页

作者： Jinghua li Yiming Zhang Yalong Huang Bing Luo li Jing Dengwei Jing International Research Center for Renewable Energy&State Key Laboratory of Multiphase Flow in Power Engineering Xi’an Jiaotong UniversityXi’an710049China School of Chemical Engineering and Technology Xi’an Jiaotong UniversityXi’an710049China

Plasmonic nanomaterial catalysis is currently at the frontier of photocatalysis,overcoming the limitations of wide bandgap semiconductors for light *** localized surface plasmon resonance(LSPR)properties allow broad ultraviolet-visible-near infrared ray(UV-vis-NIR)absorption,making it an ideal material for solar energy *** plasmonic nanostructures rely on precious *** noble metal plasmonic nanomaterials have proven to be one of the strategies for enhancing photocatalytic activity,their expensive cost and limitations in light absorption range have hindered their practical *** a result,noble-metal free plasmonic nanomaterials have risen to the top of the research priority ***,this paper reviews the fundamental principles and classification of the LSPR effect of noble-metal free plasmonic nanomaterials in photocatalytic and their recent applications in hydrogen generation,carbon dioxide reduction,and pollutant *** cases elucidate the possible working mechanism of enhanced photocatalysis by noble-metal free plasmonic ***,the challenges and future opportunities for noble-metal free plasmonic nanomaterials in energy conversion and storage are discussed and envisioned.

关键词： localized surface plasmon resonance(LSPR) noble-metal free plasmonic nanomaterials photocatalysis

Carbon quantum dots for advanced electrocatalysis

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Journal of Energy Chemistry 2021年第4期30卷 279-294页

作者： lin Tian Zhao li Peng Wang Xiuhui Zhai Xiang Wang Tongxiang li School of Materials and Chemical Engineering Xuzhou University of TechnologyXuzhou 221018JiangsuChina Analysis and Testing Center School of Materials and Chemical Engineering of Xuzhou University of TechnologyXuzhou 221018JiangsuChina School of Food and Biological Engineering Xuzhou University of TechnologyXuzhou 221018JiangsuChina

Zero-dimensional(0D)carbon quantum dots(CQDs),as a nanocarbon material in the carbon family,have garnered increasing attention in recent years due to their outstanding features of low cost,nontoxicity,large surface area,high electrical conductivity,and rich surface functional *** virtue of their rapid electron transfer and large surface area,CQDs also emerge as promising functional materials for the applications in energy-conversion sectors through ***,the rich functional groups on the surface of CQDs offer abundant anchoring sites and active sites for the engineering of multicomponent and high-performance composite *** importantly,the heteroatom in the CQDs could effectively tailor the charge distribution to promote the electron transfer via internal interactions,which is crucial to the enhancement of electrocatalytic ***,an overview about recent progress in preparing CQDs-based composites and employing them as promising electrode materials to promote the catalytic activity and stability for electrocatalysis is *** introduced CQDs could enhance the conductivity,modify the morphology and crystal phase,optimize the electronic structure,and provide more active centers and defect sites of *** establishing a deep understanding of the relationship between CQDs and electrocatalytic performances,the issues and challenges for the development of CQDs-based composites are discussed.

关键词： Carbon quantum dots Conductivity Electron transfer Electrocatalysis

Characterization of sulfide oxidation and optimization of sulfate production by a thermophilic Paenibacillus naphthalenovorans LYH-3 isolated from sewage sludge composting

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Journal of Environmental Sciences 2023年第3期125卷 712-722页

作者： li Chen Weiguang li Yi Zhao Shumei Zhang liqiang Meng Yujie Zhou School of Environment Harbin Institute of TechnologyHarbin 150090China State Key Laboratory of Urban Water Resource and Environment Harbin Institute of TechnologyHarbin 150090China Institute of Microbiology Heilongjiang Academy of SciencesHarbin 150010China

The sulfur-containing odor emitted from sludge composting could be controlled by sulfide oxidizing bacteria, yet mesophilic strains show inactivation during the thermophilic stage of composting. Aimed to investigate and characterize the thermotolerant bacterium that could oxidize sulfide into sulfate, a heterotrophic strain was isolated from sewage sludge composting and identified as Paenibacillus naphthalenovorans LYH-3. The effects of various environmental factors on sulfide oxidation capacities were studied to optimize the sulfate production, and the highest production rate (27.35%±0.86%) was obtained at pH 7.34, the rotation speed of 161.14 r/min, and the inoculation amount of 5.83%by employing BoxBehnken design. The results of serial sulfide substrates experiments indicated that strain LYH-3 could survive up to 400 mg/L of sulfide with the highest sulfide removal rate (88.79%±0.35%) obtained at 50 mg/L of sulfide. Growth kinetic analysis presented the maximum specific growth rateμm(0.5274 hr-1) after 22 hr cultivation at 50℃. The highest enzyme activities of sulfide quinone oxidoreductase (0.369±0.052 U/mg) and sulfur dioxygenase (0.255±0.014 U/mg) were both obtained at 40℃, and the highest enzyme activity of sulfite acceptor oxidoreductase (1.302±0.035 U/mg) was assessed at 50℃. The results indicated that P. naphthalenovorans possessed a rapid growth rate and efficient sulfide oxidation capacities under thermophilic conditions, promising a potential application in controlling sulfur-containing odors during the thermophilic stage of sludge composting.

关键词： Sulfide oxidizing bacteria Paenibacillus naphthalenovorans Thermophilic strains Optimization Growth kinetics Bacterial isolation

Research progress on construction strategy and technical evaluation of aircraft icing accretion protection system

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Chinese Journal of Aeronautics 2023年第10期36卷 1-23页

作者： Qiang HE Kangshuai li Zehua XU Jiwen WANG Xiaosen WANG Anling li College of Civil Aviation Safety Engineering Civil Aviation Flight University of ChinaGuanghan 618307China Key Laboratory of Icing and Anti/De-icing China Aerodynamics Research and Development CenterMianyang 621000China Henan Joint International Research Laboratory of Man Machine Environment and Emergency Management Anyang 455000China

The impact of unstable supercooled water droplets suspended in the cloud on the solid will cause its surface to freeze,and the flight safety of the aircraft will be seriously affected when flying in this *** icing protection system is an important device to reduce icing accidents and improve aircraft safety performance,which is of great significance to ensure flight *** on the energy source,this paper proposes a general strategy for constructing an aircraft icing protection system,including Active Anti-icing and De-icing(AAD)system,Passive Antiicing and De-icing(PAD)system and Composite Anti-icing and De-icing(CAD)*** principle,scope of application,advantages and disadvantages of aircraft anti-icing and de-icing technologies such as electric pulse de-icing,low-frequency piezoelectric de-icing,and hydrophobic material anti-icing are explored in detail,and the corresponding improvement measures are *** future development of aircraft anti-icing and de-icing technology is prospected,and some new ideas are provided for the improvement of aircraft anti-icing and de-icing technology.

关键词： Aircraft icing Anti-icing Construction strategy De-icing Evaluation method

Determination of the load bearing capacity of pre-stressed expandable props for ground support in underground mines

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International Journal of Mining Science and Technology 2023年第8期33卷 977-990页

作者： Kunmeng li Kaiyuan Jiang Yuanhui li Xin Wang Kai liu Shuai Xu Key Laboratory of Ministry of Education on Safe Mining of Deep Metal Mines School of Resources and Civil EngineeringNortheastern UniversityShenyang 110819China Key Laboratory of liaoning Province on Deep Engineering and Intelligent Technology School of Resources and Civil EngineeringNortheastern UniversityShenyang 110819China China-Canada Centre of Deep Mining Innovation Key Laboratory of Ministry of Education on Safe Mining of Deep Metal MinesSchool of Resources and Civil EngineeringNortheastern UniversityShenyang 110819China Department of Engineering Science University of OxfordOxford OX13PJUnited Kingdom

This paper aims to determine the load bearing capacity of pre-stressed expandable props with different geometries and load eccentricities for flexible support in underground mining or *** is deduced that the expandable device could have much higher strength(>89 MPa)by laboratory tests,and the load bearing capacity of the expandable prop may depend on the stability of the supporting steel pipe structure.A good agreement was found between the laboratory test and numerical results in terms of the load bearing capacity and the final macro-bending failure pattern for expandable props with heights of 1.5 and 2.7 m,and the theoretical calculation for the strength of traditional steel structures is not directly suitable for the expandable ***,additional numerical simulations were performed for the expandable props with different normalized slenderness ratiosλ_(n)and loading eccentric distances *** variation of stability coefficient of the expandable prop is in line with the Perry-Robertson equation and its correlation coefficients are fitted as a of 0.979 and b of *** estimating the load bearing capacity of the expandable props,the strength equation for traditional steel structures is improved by introducing a bending magnification factor and by modifying the normalized slenderness ratio to a converted slenderness *** on the underground field monitoring for the strength of expandable props with different heights,the empirical eccentric distances were back calculated,and a safety factor is introduced to obtain the designed strength of the expandable *** addition,a four-step design procedure is proposed for the expandable prop.

关键词： Pillar stability Load bearing capacity Expandable prop Slenderness ratio Eccentric distance

Bluetooth Low Energy Device Identification Based on link Layer Broadcast Packet Fingerprinting

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Tsinghua Science and Technology 2023年第5期28卷 862-872页

作者： Jinghui Zhang Xinyang li Junhe li Qiangsheng Dai Zhen ling Ming Yang School of Computer Science and Engineering Southeast UniversityNanjing 211189China School of Cyber Science and Engineering Southeast UniversityNanjing 211189China Research Institute State Grid Jiangsu Electric Power Company Ltd.Nanjing 210024China

With the rapid development of the Internet of Things(IoT),wireless technology has become an indispensable part of modern computing platforms and embedded *** device fingerprint identification is deemed as a promising solution towards enhancing the security of device access authentication and communication process in the IoT ***,the extraction of features from the network layer and its upper layers often confront restrictions from specific devices:the association with a certain wireless network and the access to the plaintext of the ***,Bluetooth Low Energy(BLE)packets have been encrypted above the link layer,which makes those features difficult to *** tackle these problems,we introduce a novel method to identify BLE devices based on the fingerprint features in the data link ***,the BLE packets are collected through a receiver based on software-defined radio ***,fields that reflect device differences in BLE broadcast packets are extracted through traffic ***,a MultiLayer Perceptron(MLP)model is employed to recognize the category of BLE *** experimental result on a dataset with 15 types of BLE devices shows that the identification accuracy of the proposed method can reach 99.8%,which accomplishes better performance over previous work.

关键词： link layer fingerprint software-defined radio Bluetooth Low Energy(BLE)