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Topological Confinement in Reversibly Interlocked Polymer Networks

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Chinese Journal of Polymer Science 2024年第2期42卷 133-140,I0004页

作者： Wan-Ting Dai Zhen-Hua Xie Yu-Bin Ke yang You Min-Zhi Rong Ming-Qiu Zhang Key Laboratory for Polymeric Composite and Functional Materials of Ministry of Education GD HPPC LabIGCMESchool of ChemistrySun Yat-sen UniversityGuangzhou510275China Spallation Neutron Source Science Center China Spallation Neutron SourceDongguan523803China Institute of High Energy Physics Chinese Academy of SciencesBeijing100049China College of Materials and Metallurgy Guizhou UniversityGuiyang550025China

Recently, we reported a series of reversibly interlocked polymer networks(RILNs), whose mechanical robustness and functionalities improvement was believed to be derived from topological interlocking of two sub-networks, although the direct evidence for the deduction is still lacking. Herein, a specially-designed RILNs system, in which the inter-component hydrogen bonds can be shielded as needed, was prepared and used to study the micro-structures of RILNs, aiming to verify the existence of mechanical interlocking in RILNs. By changing the pH of the swelling solvent, the effect exerted by the inter-component non-covalent bonds was eliminated, so detailed information of the networks structure was exposed. The small angle X-ray scattering(SAXS) and small-angle neutron scattering(SANS) results indicated that swelling-induced structural evolution of the two sub-networks mutually affected each other, even when the inter-component hydrogen bonds were absent, proving the presence of topological interlocking. The findings may help to draw a more accurate physical image and reveal the detailed structureproperty relationship of RILNs.

关键词： Reversibly interlocked polymer networks Small angle X-ray scattering Small-angle neutron scattering Topological confinement

Simplified p-i-n Perovskite Solar Cells with a Multifunctional Polyfullerene Electron Transporter

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Chinese Journal of Polymer Science 2024年第8期42卷 1060-1066页

作者： Fei-Fei Wang Tian-Xiao Liu Ze-Wei Cui Ling-Yuan Wang Yun-jie Dou Xiao-Yu Shi Si-Wei Luo Xiao-Dong Hu Zhi-Jun Ren yang-yang Liu Yu Zhao Shang-Shang Chen State Key Laboratory of Coordination Chemistry MOE Key Laboratory of High Performance Polymer Materials&TechnologySchool of Chemistry and Chemical EngineeringNanjing UniversityNanjing 21003China

In prevailing p-i-n perovskite solar cells(PSCs),solution-processible fullerene molecules are widely used as electron-transporting layers(ETLs)but they typically suffer from poor uniformity and undesirable stability ***,a separate bathocuproine(BCP)layer is needed to block hole tran sfer,increasing fabrication complexity and ***,we address these limitations by develo ping a novel polymeric ETL(named PF BCP)synthesized by polymerizing C_(60)with *** innovative material achieves both efficient electron transport and hole blocking,while its excellent uniformity minimizes interface recombination and enhances ***,our blade-coated PSCs utilizing PFBCP achieve a high power conversion efficiency exceeding 22%and retain 91%of initial efficiency after 1200 h of light *** development not only paves the way for commercially viable PSCs but also opens avenues for future ETL design to realize even more efficient and stable PSCs.

关键词： Polyfullerene Perovskite solar cells Electron transporter Stability

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子代技能溢价对亲代生育率的影响

中央财经大学学报 2024年第6期 102-114页

作者：杨琬琨金刚张霁雯辽宁大学公共管理学院、人口研究所

子代技能溢价使子代工资率在高技术部门人力资本门槛值处跃升,为将子女人力资本水平提高至预期门槛值处以获得最大的效用,大多数中等收入群体(以及少数子女天赋较低的高收入群体和子女天赋较高的低收入群体)会在子女教育方面进行额外的... 详细信息

子代技能溢价使子代工资率在高技术部门人力资本门槛值处跃升,为将子女人力资本水平提高至预期门槛值处以获得最大的效用,大多数中等收入群体(以及少数子女天赋较低的高收入群体和子女天赋较高的低收入群体)会在子女教育方面进行额外的支出。数量-质量权衡下,该群体的生育率低于其余群体,且对子女教育额外支出越高的群体,生育率越低。同时,子代技能溢价程度的提高会提高该群体占比,这不仅会降低该群体的平均生育率,也会降低社会平均生育率;一般情况下,子代人力资本门槛值的提高也具有与上述相同的影响,但如果子代技能溢价程度很低或者子代人力资本门槛值很高,该群体占比会降低、社会平均生育率会提高,不过该情况现实中极为罕见。因此,在合理降低人力资本门槛值、适度降低技能溢价程度的同时加大公共教育投入,能够成为提高生育率的有效政策选择。

关键词：技能溢价生育率数量-质量权衡

Multimodal Omics Approaches to Aging and Age‑Related Diseases

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Phenomics 2024年第1期4卷 56-71页

作者： Qianzhao ji Xiaoyu jiang Minxian Wang Zijuan Xin Weiqi Zhang jing Qu Guang‑Hui Liu State Key Laboratory of Membrane Biology Instituteof ZoologyChinese Academy of SciencesBeijing 100101China State Key Laboratory of Stem Cell and ReproductiveBiology Institute of ZoologyChinese Academy of SciencesBeijing 100101China Key Laboratory of Organ Regeneration and Reconstruction Institute of ZoologyChinese Academy of SciencesBeijing 100101China CAS Key Laboratory of Genomic and Precision Medicine Beijing Institute of GenomicsChinese Academyof Sciences and China National Center for BioinformationBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China Institute for Stem Cell and Regeneration Chinese Academyof SciencesBeijing 100101China Beijing Institute for Stem Cell and Regenerative Medicine Beijing 100101China School of Future Technology University of ChineseAcademy of SciencesBeijing 100190China Advanced Innovation Center for Human Brain Protection National Clinical Research Center for GeriatricDisordersXuanwu Hospital Capital Medical UniversityBeijing 100053China Aging Translational Medicine Center International Centerfor Aging and CancerXuanwu HospitalCapital MedicalUniversityBeijing 100053China

Aging is associated with a progressive decline in physiological capacities and an increased risk of aging-associated *** increasing body of experimental evidence shows that aging is a complex biological process coordinately regulated by multiple factors at diferent molecular ***,it is difcult to delineate the overall systematic aging changes based on single-layer ***,multimodal omics approaches,in which data are acquired and analyzed using complementary omics technologies,such as genomics,transcriptomics,and epigenomics,are needed for gaining insights into the precise molecular regulatory mechanisms that trigger *** recent years,multimodal omics sequencing technologies that can reveal complex regulatory networks and specifc phenotypic changes have been developed and widely applied to decode aging and age-related *** review summarizes the classifcation and progress of multimodal omics approaches,as well as the rapidly growing number of articles reporting on their application in the feld of aging research,and outlines new developments in the clinical treatment of age-related diseases based on omics technologies.

关键词： Multimodal omics approaches Aging Genome Epigenome

Two-dimensional atomically thin Pt layers on MXenes: The role of electronic effects during catalytic dehydrogenation of ethane and propane

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Nano Research 2024年第3期17卷 1251-1258页

作者： Zhe Li Tobias K.Misicko Fan yang Xiaopeng Liu Zhenwei Wu Xiaoyang Gao Tao Ma Jeffrey T.Miller Daniela S.Mainardi Collin D.Wick Zhenhua Zeng yang Xiao Yue Wu Department of Chemical and Biological Engineering Iowa State University618 Bissell RoadAmesIA 50011USA Institute for Micromanufacturing Louisiana Tech University505 Tech DriveRustonLA 71272USA Davidson School of Chemical Engineering Purdue University480 Stadium Mall DriveWest LafayetteIN 47907USA Michigan Center for Materials Characterization University of Michigan2800 Plymouth RdAnn Arbor MI 48109USA College of Engineering and Science Louisiana Tech UniversityRustonLA 71272USA

Atomically thin Pt nanolayers were synthesized on the surface of Mo2TiC2 MXenes and used for the catalytic dehydrogenation of ethane and propane into ethylene and propylene,two important chemicals for the petrochemical *** compared with Pt nanoparticles,the atomically thin Pt nanolayer catalyst showed superior coke-resistance(no deactivation for 24 h),high activity(turnover frequencies(TOFs)of 0.4–1.2 s^(-1)),and selectivity(>95%)toward ethylene and *** unique Pt nanolayer has a similar geometric surface to Pt nanoparticles,enabling the investigations of the electronic effect on the catalytic performance,where the geometric effect is *** is found that the electronic effect plays a critical role in dehydrogenative product selectivity and catalyst *** metal–support interaction is found dependent on the substrate and metal components,providing wide opportunities to explore high-performance MXene-supported metallic catalysts.

关键词： MXene catalysis alkane dehydrogenation nanolayers

Drag reduction characteristics of recirculation flow at rocket base in an RBCC engine under ramjet/scramjet mode

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Chinese Journal of Aeronautics 2024年第3期37卷 104-115页

作者： Menglei LI Mingbo SUN Peibo LI Daoning yang Bin AN Yizhi YAO jikai CHEN Taiyu WANG jiaoru WANG Hypersonic Technology Laboratory National University of Defense TechnologyChangsha 410073China Department of Aerospace Science and Technology Space Engineering UniversityBeijing 101416China

To reduce the drag generated by the recirculation flow at the rocket base in a RocketBased Combined Cycle(RBCC)engine operating in the ramjet/scramjet mode,a novel annular rocket RBCC engine based on a central plug cone was *** performance loss mechanism caused by the recirculation flow at the rocket base and the influence of the plug cone configuration on the thrust performance were *** indicated that the recirculation flow at the rocket base extended through the entire combustor,which creates an extensive range of the"low-kineticenergy zone"at the center and leads to an engine thrust *** plug cone serving as a surface structure had a restrictive effect on the internal flow of the engine,making it smoothly transit at the position of the large separation *** model RBCC engine could achieve a maximum thrust augmentation of 37.6%with a long plug cone that was twice diameter of the inner ***,a shorter plug cone that was half diameter of the inner isolator proved less effective at reducing the recirculation flow for a supersonic flow and induced an undesirable flow fraction that diminished the thrust ***,the effectiveness of the plug cone increased with the flight Mach number,indicating that it could further broaden the operating speed range of the scramjet mode.

关键词： Rocket-based combined cycle Ramjet/scramjet mode Plug cone Drag reduction k-x SST turbulent model

Fe-N-C core-shell catalysts with single low-spin Fe(Ⅱ)-N_(4)species for oxygen reduction reaction and high-performance proton exchange membrane fuel cells

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Journal of Energy Chemistry 2024年第6期93卷 538-546,I0013页

作者： Yan Wan Linhui Yu Bingxin yang Caihong Li Chen Fang Wei Guo Fang-Xing Xiao yangming Lin Xiamen Key Laboratory of Rare Earth Photoelectric Functional Materials Xiamen Institute of Rare Earth MaterialsHaixi InstituteChinese Academy of SciencesXiamen 361021FujianChina CAS Key Laboratory of Urban Pollutant Conversion Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021FujianChina Fujian Institute of Research on the Structure of Matter Chinese Academy of SciencesFuzhou 350002FujianChina College of Materials Science and Engineering Fuzhou UniversityNew CampusMinhou 350108FujianChina College of Chemistry and Materials Science Fujian Normal UniversityFuzhou 350117FujianChina

Fe-N-doped carbon materials(Fe-N-C)are promising candidates for oxygen reduction reaction(ORR)relative to Pt-based catalysts in proton exchange membrane fuel cells(PEMFCs).However,the intrinsic contributions of Fe-N_(4)moiety with different chemical/spin states(e.g.D1,D2,D3)to ORR are unclear since various states coexist *** the present work,Fe-N-C core-shell nanocatalyst with single lowspin Fe(Ⅱ)-N_(4)species(D1)is synthesized and identified with ex-situ ultralow temperature Mossbauer spectroscopy(T=1.6 K)that could essentially differentiate various Fe-N_(4)states and invisible Fe-O *** quantifying with CO-pulse chemisorption,site density and turnover frequency of Fe-N-C catalysts reach 2.4×10^(-9)site g^(-1)and 23 e site~(-1)s^(-1)during the ORR,***-wave potential(0.915V_(RHE))of the Fe-N-C catalyst is more positive(approximately 54 mV)than that of Pt/***,we observe that the performance of PEMFCs on Fe-N-C almost achieves the 2025 target of the US Department of Energy by demonstrating a current density of 1.037 A cm^(-2)combined with the peak power density of 0,685 W cm^(-2),suggesting the critical role of Fe(Ⅱ)-N_(4)site(D1).After 500 h of running,PEMFCs still deliver a power density of 1.26 W cm^(-2)at 1.0 bar H_(2)-O_(2),An unexpected rate-determining step is figured out by isotopic labelling experiment and theoretical *** work not only offers valuable insights regarding the intrinsic contribution of Fe-N_(4)with a single spin state to alkaline/acidic ORR,but also provides great opportunities for developing high-performance stable PEMFCs.

关键词： Fuel cells Oxygen reduction reaction Non-platinum group metals(PGMs) Isotopic labelling Active site TOF

基于扰动观测器的水面无人船自适应模糊控制器设计

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控制理论与应用 2024年第2期41卷 261-272页

作者：董颖慧陈健吕成兴张子叶余继恒青岛理工大学信息与控制工程学院山东青岛266520 山东科技大学数学与系统科学学院山东青岛266590

为了使水面无人船(USV)获得更好的跟踪性能,本文设计了基于扰动观测器和命令滤波器的自适应模糊控制器.对于该系统存在建模不确定性和外部环境的扰动,采用模糊逻辑系统(FLS)和一个新的扰动观测器对其进行逼近和补偿.在扰动观测器和控制... 详细信息

为了使水面无人船(USV)获得更好的跟踪性能,本文设计了基于扰动观测器和命令滤波器的自适应模糊控制器.对于该系统存在建模不确定性和外部环境的扰动,采用模糊逻辑系统(FLS)和一个新的扰动观测器对其进行逼近和补偿.在扰动观测器和控制器中加入了一个新的自适应参数,用来改善控制精度.基于此,本文设计了命令滤波反步控制方法,可以保证系统在所有状态下都是有界的,且跟踪误差在有限时间内小于规定的精度.仿真结果显示该方法有效,且可以满足给定的控制精度.

关键词：模糊逻辑水面无人船扰动观测器 Lyapunov稳定性定理自适应控制系统

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基于交叉注意力机制的多模态感知融合方法

中国公路学报 2024年第3期37卷 181-193页

作者：张炳力潘泽昊姜俊昭张成标王怿昕杨程磊合肥工业大学汽车与交通工程学院安徽合肥230041 安徽省智能汽车工程实验室安徽合肥230009

针对智能汽车道路目标检测任务中单一传感器感知能力有限、多传感器后融合处理复杂等问题,提出了一种基于Transformer交叉注意力机制的多模态感知融合方法。首先,利用交叉注意力机制能较好地融合多模态信息的优势,搭建了基于深度学习方... 详细信息

针对智能汽车道路目标检测任务中单一传感器感知能力有限、多传感器后融合处理复杂等问题,提出了一种基于Transformer交叉注意力机制的多模态感知融合方法。首先,利用交叉注意力机制能较好地融合多模态信息的优势,搭建了基于深度学习方式的端到端融合感知网络,用以接收视觉与点云检测网络的输出,并进行后融合处理。其次,对点云检测网络的三维目标信息进行高召回处理,与视觉图像检测器输出的道路目标信息一同作为网络的输入。最后,通过网络实现二维目标信息向三维信息的融合,输出对三维目标检测信息的修正,从而得到准确度更高的后融合检测信息。在KITTI公开数据集上的验证指标表明,通过所提融合方法引入二维检测信息后,相比较PointPillars、PointRCNN、PV-RCNN及CenterPoint四种基准方法,对车辆、骑行人、行人3种类别的综合平均提升分别为7.07%、2.82%、2.46%、1.60%。通过与基于规则的后融合方法对比,所提融合网络在行人和骑行人中等、困难样本检测上,分别有平均1.88%与4.90%的提升。进一步表明所提方法具有更强的适应性与泛化能力。最后,进行了实车试验平台的搭建及算法验证,选取实车试验场景进行可视化定性分析,在实际道路场景下验证了所提检测方法与网络模型。

关键词：汽车工程多模态融合交叉注意力机制三维目标检测后融合信息修正