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Nano Research 2017年第3期10卷 1044-1055页

作者： Ji Chan Park Shin Wook Kang Jeong-Chul Kim Jae In Kwon Sanha Jang Geun Bae Rhim Mijong Kim Dong Hyun Chun Ho-Tae Lee Heon jung Hyunjoon Song jung-li yang Clean Fuel Laboratory Korea Institute of Energy Research Daejeon 34129 Republic of Korea Advanced Energy Technology University of Science and Technology Daejeon 34713 Republic of Korea Center for Nanomaterials & Chemical Reactions Institute for Basic Science Daejeon 34141 Republic of Korea Department of Chemistry Korea Advanced Institute of Science and Technology Daejeon 34141 Republic of Korea

A cobalt-silica hybrid nanocatalyst bearing small cobalt particles of diameter -5 nm was prepared through a hydrothermal reaction and hydrogen reduction. The resulting material showed very high CO conversion （〉82%） and high hydrocarbon productivity （-1.0gHC·gcat^-1·h^-1 ） with high activity （-8.5 × 10^-5 ***^-1.s-1） in the Fischer-Tropsch synthesis reaction.

关键词： hybrid nanostructure Fischer-Tropsch synthesis thermal stability metal silicate hydroxide cobalt catalyst

Boron-10 stimulated helium production and accelerated radiation displacements for rapid development of fusion structural materials

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Journal of Materiomics 2024年第2期10卷 377-385页

作者： Yunsong jung Ju li Department of Nuclear Science and Engineering and Department of Materials Science and Engineering Massachusetts Institute of TechnologyCambridgeMA02139USA Korea Institute of Fusion Energy Daejeon34133Republic of Korea

Boron doping,combined with neutron capture in fission reactors,has been used to simulate the helium effect on fusion structural ***,inhomogeneous helium bubble formation was often observed due to boron segregation to grain *** excess radiation displacements due to^(10)B(n,α)^(7)li reaction,the high-energy lithium and helium ions,also were not accounted for,which can significantly accelerate the displacements-per-atom(dpa)accumulation alongside helium production(appm).Hereby an isotopically pure^(10)B doping approach is proposed to simulate the extreme envi-ronment inside fusion reactors with a high He appm-to-dpa ratio of about 10,which is about 10^(2)×larger than in fission *** modeling showed that~13%of total radiation displacement was induced by^(10)B(n,α)^(7)li in the case of 1000 appm^(10)B doped Fe samples,which becomes even greater with increasing^(10)B *** homogenous radiation damage and helium generation are pre-dicted for grain sizes less than 1 mm,even if the boron partially formed precipitates or segregates on grain *** studies with various^(10)B doping(and^(235)U-codoping)levels in research reactors showed the estimated helium generation and radiation damage would significantly mimic fusion conditions and greatly expedite fusion materials testing,from many years down to months.

关键词： Fusion power reactor Helium transmutation He appm-to-dpa ratio Boron-10 doping Accelerated materials testing

Alignment efficient image-sentence retrieval considering transferable cross-modal representation learning

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Frontiers of Computer Science 2024年第1期18卷 77-91页

作者： yang yang Jinyi GUO Guangyu li Lanyu li Wenjie li Jian yang School of Computer Science and Engineering Nanjing University of Science and TechnologyNanjing 210094China Department of Computing Hong Kong Polytechnic UniversityHong Kong 100872China State Key Lab.for Novel Software Technology Nanjing UniversityNanjing 210094China 14th Research Institute of China Electronics Technology Group Corporation Nanjing 210094China guangyu.li2017@***

Traditional image-sentence cross-modal retrieval methods usually aim to learn consistent representations of heterogeneous modalities,thereby to search similar instances in one modality according to the query from another modality in *** basic assumption behind these methods is that parallel multi-modal data(i.e.,different modalities of the same example are aligned)can be obtained in *** other words,the image-sentence cross-modal retrieval task is a supervised task with the alignments as ***,in many real-world applications,it is difficult to realign a large amount of parallel data for new scenarios due to the substantial labor costs,leading the non-parallel multi-modal data and existing methods cannot be used *** the other hand,there actually exists auxiliary parallel multi-modal data with similar semantics,which can assist the non-parallel data to learn the consistent ***,in this paper,we aim at“Alignment Efficient Image-Sentence Retrieval”(AEIR),which recurs to the auxiliary parallel image-sentence data as the source domain data,and takes the non-parallel data as the target domain *** single-modal transfer learning,AEIR learns consistent image-sentence cross-modal representations of target domain by transferring the alignments of existing parallel ***,AEIR learns the image-sentence consistent representations in source domain with parallel data,while transferring the alignment knowledge across domains by jointly optimizing a novel designed cross-domain cross-modal metric learning based constraint with intra-modal domain adversarial ***,we can effectively learn the consistent representations for target domain considering both the structure and semantic ***,extensive experiments on different transfer scenarios validate that AEIR can achieve better retrieval results comparing with the baselines.

关键词： image-sentence retrieval transfer learning semantic transfer structure transfer

Isomeric fluorescence sensors for wide range detection of ionizing radiations

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Defence Technology（防务技术） 2024年第4期34卷 247-257页

作者： Jimin Han Tianyu yang li yang Yuanjian li State Key Laboratory of Explosion Science and Technology of China Beijing Institute of TechnologyBeijing 100081China Chongqing Innovation Center Beijing Institute of TechnologyChongqing 401120China

In order to achieve a wider range of ionizing radiations detection,novel fluorescence sensing materials have been developed that utilize the fluorescence enhancement phenomenon caused by the intramolecular photoinduced electron transfer(PET)*** perylene diimide isomers PDI-P and PDI-B were designed and synthesized,and their molecular structures were characterized by high-resolution Fourier transform mass spectrometry(HRMS),nuclear magnetic resonance hydrogen and carbon spectroscopy(~1H and~(13)C NMR).The interaction between ionizing radiation and fluorescent molecules was simulated by HCl *** results show that combining PDIs and HCl can improve fluorescence through the retro-PET *** the similarities in chemical structures,the fluorescent enhancement multiple of PDI-B with aromatic amine as electron donor is much higher than that of PDI-P with alkyl *** the direct irradiation experiments of ionizing radiation,the emission enhancement multiples of PDI-P and PDI-B are 2.01 and 45.4,***,density functional theory(DFT)and time-dependent density functional theory(TDDFT)calculations indicate that the HOMO and HOMO-1 energy ranges of PDI-P and PDI-B are 0.54 e V and 1.13 e V,respectively.A wider energy range has a stronger driving force on electrons,which is conducive to fluorescence *** femtosecond transient absorption spectroscopy(fs-TAS)and transient fluorescence spectroscopy(TFS)tests show that PDI-B has shorter charge separation lifetime and higher electron transfer rate *** both isomers can significantly reduce LOD during PET process,PDI-B with aromatic amine has a wider detection range of 0.118—240 Gy due to its larger emission enhancement,which is a leap of three orders of *** breaks through the detection range of gamma radiation reported in existing studies,and provides theoretical support for the further study of sensitive and effective new materials for ionizing radiation dete

关键词： Perylene imide Intramolecular PET Ionizing radiation detection Fluorescence sensor Isomers

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Development in oxide metallurgy for improving the weldability of high -strength low-alloy steel-Combined deoxidizers and microalloying elements

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International Journal of Minerals,Metallurgy and Materials 2024年第6期31卷 1263-1284页

作者： Tingting li Jian yang State Key Laboratory of Advanced Special Steel School of Materials Science and EngineeringShanghai UniversityShanghai 200444China

The mechanisms of oxide metallurgy include inducing the formation of intragranular acicular ferrite(IAF)using micron-sized inclusions and restricting the growth of prior austenite grains(PAGs)by nanosized particles during *** chaotically oriented IAF and refined PAGs inhibit crack initiation and propagation in the steel,resulting in high impact *** work summarizes the com-bined effect of deoxidizers and alloying elements,with the aim to provide a new perspective for the research and practice related to im-proving the impact toughness of the heat affected zone(HAZ)during the high heat input *** complex deoxidation with other strong deoxidants,such as Mg,Ca,Zr,and rare earth metals(REMs),can improve the toughness of the heat-affected zone(HAZ)by re-fining PAGs or increasing IAF ***,it is difficult to identify the specific phase responsible for IAF nucleation because ef-fective inclusions formed by complex deoxidation are usually *** alloying elements,such as C,Si,Al,Nb,or Cr,con-tents can impair HAZ toughness.A high C content typically increases the number of coarse carbides and decreases the potency of IAF ***,Cr,or Al addition leads to the formation of undesirable *** reduces the high-temperature stability of the ***,V,and B can enhance HAZ ***-containing precipitates present good thermal *** or V(C,N)is ef-fective in promoting IAF nucleation due to its good coherent crystallographic relationship with *** formation of the B-depleted zone around the inclusion promotes IAF *** interactions between alloying elements are complex,and the effect of adding dif-ferent alloying elements remains to be *** the future,the interactions between various alloying elements and their effects on ox-ide metallurgy,as well as the calculation of the nucleation effects of effective inclusions using first principles calculations will become the focus of

关键词： oxide metallurgy technology heat affected zone high-strength low-alloy steel intragranular acicular ferrite microalloying element

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APF-GAN:Exploring asymmetric pre-training and fine-tuning strategy for conditional generative adversarial network

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Computational Visual Media 2024年第1期10卷 187-192页

作者： Yuxuan li lingfeng yang Xiang li College of Computer Science Nankai UniversityTianjinChina School of Computer Science and Engineering Nanjing University of Science and TechnologyNanjingChina

The use of generative adversarial network(GAN)-based models for the conditional generation of image semantic segmentation has shown promising results in recent ***,there are still some limitations,including limited diversity of image style,distortion of detailed texture,unbalanced color tone,and lengthy training *** address these issues,we propose an asymmetric pre-training and fine-tuning(APF)-GAN model.

关键词： tuning network asymmetric

light People:*** Mazur speaks about ultrafast optics and education

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light(Science & Applications) 2024年第3期13卷 402-406页

作者： Chenzi Guo yang li Changchun Institute of Optics Fine Mechanics and PhysicsChinese Academy of SciencesChangchunChina State Key Laboratory of Precision Measurement Technology and Instrument Department of Precision InstrumentTsinghua UniversityBeijingChina

*** Mazur is a great influencer over and beyond the optics *** a physicist,he is a pioneer of ultrafast optics and was one of the inventors of colliding-pulse mode-locked *** an educator,he not only gave talks to thousands,but also revolutionized teaching with his globally renowned methodology“Peer Instruction”.As a leader and entrepreneur,he co-founded several companies and was President of Optica(formerly the Optical Society)and currently is the Chair of the Optica ***,light:Science&Applications talked with *** Mazur about his opinions on research,education and *** full interview video can be found in the Supplementary File.

关键词： optics education companies

RMPC-Based Visual Servoing for Trajectory Tracking of Quadrotor UAVs With Visibility Constraints

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IEEE/CAA Journal of Automatica Sinica 2024年第9期11卷 2027-2029页

作者： Qifan yang Huiping li School of Marine Science and Technology Northwestern Polytechnical UniversityXi’an 710072China

Dear Editor,This letter deals with the tracking problem of quadrotors subject to external disturbances and visibility constraints by designing a robust model predictive control(RMPC) scheme. According to the imagebase... 详细信息

关键词： Visual image visibility

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Three-stage niobium mineralization at Bayan Obo, China

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National Science Review 2024年第4期11卷 102-110页

作者： Yan Yu yang li Yu liu Xiao-Xiao ling li-Guang Wu li yang Lan yang Bo yang Yong-Gang Zhao Xian-Hua li State Key Laboratory of lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences College of Earth and Planetary Science University of Chinese Academy of Sciences Ministry of Education Key Laboratory of Orogenic Belts and Crustal Evolution School of Earth and Space SciencesPeking University Mining Research Institute Baotou Iron and Steel(Group) Co.LTD State Key Laboratory of Baiyunobo Rare Earth Resource Research and Comprehensive Utilization

The Chinese Bayan Obo deposit is a world-class rare earth element(REE) deposit with considerable niobium(Nb) and iron(Fe) resources. A complete genetic understanding on all metals is fundamental for establishing genetic models at Bayan Obo. With extensive research being focused on REE enrichment, the timing and controls of Nb enrichment remain unresolved at Bayan Obo, which is mainly due to the challenges in dating, i.e. multistage thermal events, fine-grained minerals with complex textures and the rare occurrence of uranium-enriched minerals with mature dating methods. Based on robust geological and petrographic frameworks, here we conducted ion probe uranium-lead(U-Pb) dating of ferrocolumbite to unravel the timing, hence the genesis of Nb mineralization. Three types of hydrothermal ferrocolumbites—key Nb-bearing minerals—are identified based on their textures and mineral assemblages. They yield U-Pb ages of 1312 ± 47 Ma(n = 99), 438 ± 7 Ma(n = 93), and 268 ± 5 Ma(n = 19), respectively. In line with deposit geology, we tentatively link the first, second and third stage Nb mineralization to Mesoproterozoic carbonatite magmatism, ubiquitous early Paleozoic hydrothermal activity, and Permian granitic magmatism, respectively. While quantifying the contribution of metal endowment from each stage requires further investigation, our new dates highlight that multi-stage mineralization is critical for Nb enrichment at Bayan Obo, which may also have implications for the enrichment mechanism of Nb in REE deposits in general.

关键词： niobium mineralization U-Pb dating ferrocolumbite Bayan Obo

Failure mechanisms and surface treatment processes of thermal barrier coatings:Review

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Chinese Journal of Aeronautics 2024年第9期37卷 20-40页

作者： Hao li Shengqiang yang Xiuhong li Wenhui li College of Mechanical and Vehicle Engineering Taiyuan University of TechnologyTaiyuan 030024China Shan.xi Province Key Laboratory of Precise Machining Taiyuan University of TechnologyTaiyuan 030024China College of Aeronautics and Astronautics Taiyuan University of TechnologyTaiyuan 030024China

Thermal Barrier Coatings(TBCs)technology is key to improving the service temperature and the productivity of aircraft *** performance and failure life of TBCs are strongly influenced by surface integrity and ***,recognizing failure mechanisms and developing effective surface treatment processes are crucial for further improving the reliability and durability of *** paper explains the primary reasons for TBC failure,emphasizing on how integrity of surface and interface influences interfacial oxidation,high-temperature erosion,and Calcium-Magnesium-Alumina-Silicate(CMAS)***,this paper completely and rigorously evaluates the research status of TBCs surface treatment processes,including the characteristics and effects of various processes,and describes the requirements and goals of pretreatment and *** addition,a potential direction for the development and application of TBCs surface treatment is suggested.

关键词： Thermal BarrierCoatings(TBCs) Failure Surface treatment processes Processing goals Mass finishing