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Semi-supervised learning via manifold regularization

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The Journal of China Universities of Posts and Telecommunications 2012年第6期19卷 79-88页

作者： MAO Yu ZHOU Yan-quan li rui-fan WANG Xiao-jie ZHONG Yi-xin School of Telecommunication Engineering Beijing University of Posts and Telecommunications

This paper proposes a novel graph-based transductive learning algorithm based on manifold regularization. First, the manifold regularization was introduced to probabilistic discriminant model for semi-supervised classification task. And then a variation of the expectation maximization （EM） algorithm was derived to solve the optimization problem, which leads to an iterative algorithm. Although our method is developed in probabilistic framework, there is no need to make assumption about the specific form of data distribution. Besides, the crucial updating formula has closed form. This method was evaluated for text categorization on two standard datasets, 20 news group and Reuters-21578. Experiments show that our approach outperforms the state-of-the-art graph-based transductive learning methods.

关键词： manifold regularization semi-supervised learning transductive learning expectation maximization algorithm classification text categorization

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Self-doping active sites in microbe-derived carbonaceous electrocatalysts for the oxygen reduction reaction performance

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Nano Research 2024年第8期17卷 6803-6819页

作者： Xiaofeng Xiao Xiaochun Tian Junpeng li fan Yang rui Bai Feng Zhao Key Laboratory of Urban Pollutant Conversion Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China University of Chinese Academy of Sciences Beijing 100049China

Microorganisms are rich in heteroatoms,which can be self-doped to form active sites during pyrolysis and loaded on microbederived carbonaceous *** recent years,microbe-derived carbonaceous materials,characterized with abundant selfdoping sites,have been continuously developed as cost-effective electrocatalysts for oxygen reduction reaction(ORR).To fully unlock the catalytic potential of microbe-derived carbonaceous materials,a comprehensive analysis of catalytic sites and mechanisms for ORR is *** paper provides a summary of the ORR catalytic performance of microbe-derived carbonaceous materials reported to date,with a specific focus on the self-doping sites introduced during their pyrolytic *** highlights the mono-or co-doping sites involving nonmetallic elements such as oxygen(O),nitrogen(N),phosphorus(P),and sulfur(S)atoms,as well as covers the doping of metallic iron(Fe)atoms with various coordination configurations in microbe-derived carbonaceous *** the impact of these self-doping sites on ORR catalytic performance can guide the design of doping sites in microbe-derived carbonaceous *** approach has the potential to maximize electrocatalytic activity of microbe-derived carbonaceous materials and contributes to the development of more efficient and cost-effective carbonaceous electrocatalysts.

关键词： electrocatalysis heteroatoms self-doped single atom catalyst microbe-derived carbonaceous material

Ternary layered boride MoAlB:A novel thermo-regulation microwave absorbing ceramic material

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Journal of Advanced Ceramics 2024年第5期13卷 699-710页

作者： Zhangjue Wang fan Zhang Nannan Wang Wei li Yongqiang Chen Hailong Wang rui Zhang Yanqiu Zhu Bingbing fan School of Material Science and Engineering Zhengzhou UniversityZhengzhou 450001China Henan Academy of Sciences Zhengzhou 450046China State Key Laboratory of Featured Metal Materials and life Cycle Safety for Composite Structures MOE Key Laboratory of New Processing Technology for Nonferrous Metals MaterialsSchool of ResourcesEnvironment and MaterialsGuangxi UniversityNanning 530004China Department of Materials and Earth Sciences Technical University of DarmstadtDarmstadt 64287Germany School of Material Science and Engineering Luoyang Institute of Science and TechnologyLuoyang 471023China Department of Engineering Faculty of EnvironmentScience and EconomyUniversity of ExeterExeter EX44QFUK

In the context of the fifth-generation(5G)smart era,the demand for electromagnetic wave(EMW)-absorbing materials has become increasingly prominent,so it is necessary to explore promising candidate *** work focuses on the exploration of the material absorbing properties of a MoAlB MAB(MAB represents a promising group of alternatives,where M stands for a transition metal,A typically denotes Al,and B is boron)phase ***,the first-principles calculations were performed to reveal the unique crystal and layered structure of the MoAlB ceramics and to predict their potential for use as an EMW absorption ***,a series of MoAlB ceramics were synthesized at temperatures ranging from 800 to 1300℃,and the influence of temperature on the phase compositions and microstructures of the obtained MoAlB ceramics was characterized and ***,the practical EMW absorption performance of the prepared MoAlB ceramics was evaluated via a combination of experiments and radar cross-sectional *** MoAlB sample synthesized at 900℃ exhibits superior EMW absorption performance,achieving an impressive minimum reflection loss(RL)of−50.33 *** unique layered structure and good electrical conductivity of the MoAlB samples are the main reasons for their enhanced wave absorption performance,which provides interfacial polarization and multiple dielectric loss ***,this study not only contributes to the understanding of the preparation of MoAlB materials but also provides potential guidance for their utilization in the realm of electromagnetic wave absorption.

关键词： MoAlB electronic band structure electromagnetic wave(EMW)absorption layered ternary boride density of states

Superhydrophobic melamine sponge prepared by radiation-induced grafting technology for efficient oil-water separation

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NUCLEAR SCIENCE AND TECHNIQUES 2024年第9期35卷 1-12页

作者： Sun, Ying Wang, Wen-rui li, Dan-Yi Xu, Si-Yi lin, lin Lu, Man-li fan, Kai Xing, Chen-Yang li, lin-fan li, Ji-Hao Chinese Acad Sci Shanghai Inst Appl Phys Shanghai 201800 Peoples R China Univ Chinese Acad Sci Beijing 100049 Peoples R China Chongqing Coll Elect Engn Sch Architecture & Mat Chongqing 401331 Peoples R China Shenzhen Univ Coll Phys & Optoelect Engn Ctr Stretchable Elect & NanoSensors Key Lab Optoelect Devices & SystMinist Educ Shenzhen 518060 Peoples R China

This paper presents a superhydrophobic melamine (ME) sponge (ME-g-PLMA) prepared via high-energy radiation-induced in situ covalent grafting of long-alkyl-chain dodecyl methacrylate (LMA) onto an ME sponge for efficient oil-water separation. The obtained ME-g-PLMA sponge had an excellent pore structure with superhydrophobic (water contact angle of 154 degrees\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$154\circ$$\end{document}) and superoleophilic properties. It can absorb various types of oils up to 66-168 times its mass. The ME-g-PLMA sponge can continuously separate oil slicks in water by connecting a pump or separating oil underwater with a gravity-driven device. In addition, it maintained its highly hydrophobic properties even after long-term immersion in different corrosive solutions and repeated oil adsorption. The modified ME-g-PLMA sponge exhibited excellent separation properties and potential for oil spill cleanup.

关键词： Radiation-induced graft polymerization Oil-water separation Sponge Superhydrophobic OIL/WATER SEPARATION LAURYL METHACRYLATE POLYURETHANE SPONGE ABSORPTION ABSORBENT STRATEGY REMOVAL AEROGEL SPILL FOAM

Flexible mille-feuille structure electromagnetic interference shielding film with excellent thermal conductivity and Joule heating

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Nano Research 2024年第5期17卷 4544-4554页

作者： Dingwen Yin Huijuan Xiu Simin Wang Yanfei Pan Na li rui Cheng Shaoyan Huang Sha fan Jinbao li College of Bioresources Chemical&Materials Engineering Shaanxi University of Science&TechnologyXi'an 710021China National Demonstration Center for Experimental light Chemistry Engineering Education Shaanxi Provincial Key Laboratory of Papermaking Technology and Specialty Paper DevelopmentXi'an 710021China College of Material Science and Art Design Inner Mongolia Agricultural UniversityHohhot 010018China

The intelligent electronic devices have urgent demands for electromagnetic interference(EMI)shielding films with excellent heat dissipation ***,it is challenging to obtain excellent EMI shielding and thermal conductivity performances ***,inspired by mille-feuille structure,the multifunctional EMI shielding films developed by a layer-by-layer self-assembly and hot-pressing *** ingenious introduction of silver nanoparticles(AgNPs)with large specific surface area and highly conductive into the network formed by TEMPO-oxidized cellulose nanofibrils(TOCNFs)with large aspect ratio to form the TOCNFs/*** the graphene nanoplates(GNPs)with high conductivity loss distributed alternately with TOCNFs/AgNPs to construct mille-feuille structure,which had highly efficient conductive network,complete thermally conduction pathway and rich heterogeneous ***,the designed films presented high electrical conductivity of 8520 S/cm,superb EMI effectiveness(SE)of 98.05 dB,and excellent thermal conductivity of 18.82 W/(m·K).Furthermore,the films possessed outstanding Joule heating performances with low voltages,including high heating temperature(100℃),fast response time(lity and ***,such high-performance EMI shielding films with fascinating thermal conductivity and Joule heating performances have substantial application in flexible electronics,electromagnetic waves shielding and thermal management.

关键词： TEMPO-oxidized cellulose nanofibrils/silver nanoparticles(TOCNFs/AgNPs) mille-feuille structure electromagnetic interference shielding thermal conductivity Joule heating

Biomimetic porous silicon oxycarbide ceramics with improved specific strength and efficient thermal insulation

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Journal of Materials Science & Technology 2024年第1期168卷 185-193页

作者： Zhuoqing Zhang Jinghan li Lei Cao Yu Shi Huajie Yang rui Yang fan Xie Xing Zhang Shi-changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaHefei 230026China School of Materials Science and Engineering Shenyang Ligong UniversityShenyang 110159China Shenyang Aircraft Design and Research Institute Shenyang 110035China

Considering the challenge of aerodynamic heating,the development of high-performance insulating ce-ramic materials with lightweight and low thermal conductivity is crucially important for aerospace vehi-cles to achieve flight at high speed for a long *** this work,macro-porous silicon oxycarbide(SiOC)ceramics with directional pores(DP-SiOC)(mean pore size of 88.1μm)were prepared using polysiloxane precursors via freeze casting and photocrosslinking,followed by *** DP-SiOC samples were lightweight(density∼0.135 g cm^(-3))with a porosity of 90.4%,which showed good shapability through the molding of polysiloxane *** DP-SiOC samples also exhibited an ultra-low thermal con-ductivity of 0.048 W(m K)^(-1)at room temperature,which can also withstand heat treatment at 1200°C for 1 *** addition,scaffolds with triply periodic minimal surfaces(TPMS)were fabricated using digital light processing(DLP)printing,which was further filled with polysiloxane precursors for increasing the strength of *** TPMS scaffolds filled with macro-porous SiOC ceramics(TPMS-DP-SiOC)showed good integration between TPMS and macro-pore structures,which had a porosity∼75%and high specific strength of 9.73×10^(3)N m kg^(-1).The thermal conductivity of TPMS-DP-SiOC samples was 0.255 W(m K)^(-1)at room *** biomimetic TPMS-DP-SiOC ceramics developed in this study are likely used for thermal protection systems.

关键词： Thermal insulation light weight Macro-porous ceramics SiOC

Unlocking single-atom catalysts via amorphous substrates

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Nano Research 2024年第5期17卷 3533-3546页

作者： Bohua Sun Mingyuan Xu Xiaoxia li Baohong Zhang rui Hao Xiaoyu fan Binbin Jia Dingshun She School of Engineering and Technology China University of Geosciences(Beijing)Beijing 100083China Zhengzhou Institute China University of Geosciences(Beijing)Zhengzhou 451283China College of Materials and Chemical Engineering Key Laboratory of Inorganic Nonmetallic Crystalline and Energy Conversion MaterialsChina Three Gorges UniversityYichang 443002China School of Chemistry Beihang UniversityBeijing 100191China Chinese Academy of Sciences(CAS)Key Laboratory of Nanosystem and Hierarchy Fabrication CAS Center for Excellence in NanoscienceNational Center for Nanoscience and TechnologyBeijing 100190China National Engineering Research Center of Nonferrous Metals Materials and Products for New EnergyChina GRINM Group Co.Ltd.Beijing 100088China

Single-atom catalysts(SACs)reveal great potential for application in catalysis due to their fully exposed active *** general,single atoms(SAs)and the coordination substrates need to have strong interactions or charge transfer to ensure the atomic dispersion,which requires the selection of a suitable substrate to stabilize the target *** studies have demonstrated that amorphous materials with abundant defects and coordinatively unsaturated sites can be used as substrates for more efficient capturing SAs,further enhancing the catalytic *** this review,we discuss recent research progress of SAs loaded on amorphous substrates for enhanced catalytic ***,we summarize the commonly used amorphous substrates for stabilizing ***,we present several advanced applications of amorphous SACs in the field of catalysis,including electrocatalysis and *** then,we also clarify the synergistic mechanism between SAs and amorphous substrate on catalytic ***,we summarize the challenges with our personal views and provide a critical outlook on how amorphous SACs continue to evolve.

关键词： single-atoms amorphous substrate synthetic strategy catalysis

Identi?cation and Analysis of the Intermediates from Photodegradation of 3,3′-diamino-4,4′-azoxyfurazan (DAAF)by SERS and HPLC–MS/MS

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Journal of Analysis and Testing 2024年第03期8卷 351-360页

作者： Qi Wu Zhenqi Zhang Wenxu Zheng Juan li Nan Ma rui li Bo Yang Weimiao Wang Xiaodong li Meikun fan Faculty of Geosciences and Environmental Engineering Southwest Jiaotong University Institute of Chemical Materials China Academy of Engineering Physics College of Materials and Energy South China Agricultural University Southwest University of Science and Technology

Understanding the structural changes and degradation mechanisms of organic pollutants is critical in environmental *** this work, a xenon lamp was used as an analog light source to simulate the eff ect of sunlight on 3,3′-diamino-4,4′-azoxyfurazan (DAAF) in aqueous solution. Combining high-performance liquid chromatography coupled with tandem mass spectrometry (HPLC–MS/MS), surface-enhanced Raman spectroscopy (SERS) with density functional theory (DFT), the degradation intermediates and mechanisms of DAAF were investigated. The sequential breakdown of the–NH 2and–O–N=bonds, followed by the removal of atomic O from–N=N(O)–, was emphasized and investigated using two-dimensional correlation spectroscopy (2D-COS) and SERS spectra. Three intermediates with mass-to-charge ratios (m/z) 181, 251 and180 were identifi ed and characterized by integrating experimental SERS data with DFT-calculated Raman spectra based on structures hypothesized from MS spectra. The fi ndings from HPLC–MS and SERS not only corroborate each other but also provide a foundation for a detailed examination of the DAAF degradation process.

关键词： DAAF High-performance liquid chromatography coupled with tandem mass spectrometry (HPLC–MS/MS) Photodegradation products Reaction pathways Surface-enhanced Raman spectroscopy (SERS)

A review of linear friction welding of Ni -based superalloys

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International Journal of Minerals,Metallurgy and Materials 2024年第6期31卷 1382-1391页

作者： Xiawei Yang Tingxi Meng Qiang Chu Yu Su Zhenguo Guo rui Xu Wenlong fan Tiejun Ma Wenya li State Key Laboratory of Solidification Processing Shaanxi Key Laboratory of Friction Welding TechnologiesNorthwestern Polytechnical UniversityXi’an 710072China Xi’an Aerospace Engine Co.Ltd. Xi’an 710100China

Ni-based superalloys are one of the most important materials employed in high-temperature applications within the aerospace and nuclear energy industries and in gas turbines due to their excellent corrosion,radiation,fatigue resistance,and high-temperature *** friction welding(LFW)is a new joining technology with near-net-forming characteristics that can be used for the manu-facture and repair of a wide range of aerospace *** paper reviews published works on LFW of Ni-based superalloys with the aim of understanding the characteristics of frictional heat generation and extrusion deformation,microstructures,mechanical proper-ties,flash morphology,residual stresses,creep,and fatigue of Ni-based superalloy weldments produced with LFW to enable future optim-um utilization of the LFW process.

关键词： Ni-based superalloys linear friction welding microstructures mechanical properties flash morphology

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