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High-performance poly(aromatic pyridine) copolymers with crown ether moieties for high temperature polymer electrolyte membrane fuel cells

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Science China Chemistry 2025年

作者： Qian wang Songhao Zhao Yunpeng Guo w.i w.i lele wang Jingshuai Yang Department of Chemistry College of Sciences Northeastern University institute of Metal Research Chinese Academy of Sciences

This study concentrates on the development of high temperature polymer electrolyte membranes（HT-PEMs）, w.ich are essential components for HT-PEM fuel cells（HT-PEMFCs）. Although the phosphoric acid（PA）-doped polybenzimidazole（PBi） has been regarded as the successful HT-PEM, this system still suffers from several challenges, including the use of carcinogenic monomers, complex synthesis procedures, and poor solubility in organic solvents. To develop more cost-effective, readily synthesized and high-performance alternatives, this study employs a simply superacid-catalyzed Friedel-Crafts reaction to synthesize a series of poly（triphenyl-co-dibenzo-18-crown-6 pyridine） copolymers, denoted as P(TPx%-co-CEy%), using ptriphenyl, dibenzo-18-crown-6 and 4-acetylpyridine as monomers. The copolymerized hydrophilic and bulky crown ether unites introduce large free volumes and multiple interaction sites with PA molecules, as elucidated by theoretical *** microphase separation structures are formed as confirmed by atomic force microscope（AFM）, transmission electron microscopy（TEM） and small-angle X-ray scattering（SAXS）. Thus P(TPx%-co-CEy%) membranes exhibit excellent PA absorption and proton conduction abilities. For example, after immersing in 85 wt% PA at 30 °C, the P(TP91%-co-CE9%) membrane achieves a PA doping content of 205% and a high conductivity of 0.138 S cm-1at 180 °C, w.ile maintaining a tensile strength of 7.5 MPa at room temperature. without humidification and backpressure, the peak power density of an H2-O2cell equipped with P(TP91%-co-CE9%)/205%PA reaches nearly 1200 mw cm-2, representing one of the highest performances reported for PA-doped HT-PEMs to date. This work demonstrates the enormous potential of poly（triphenyl-co-crown ether pyridine） membranes in the HT-PEMFC applications.

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Engineering N3C vacancies in hierarchical porous carbon nitride nanosheets for room temperature ultradeep photocatalytic aerobic oxidative desulfurization

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Science China Chemistry 2025年

作者： Yina Nie w.ijie Yang Xin wang Xiang Li lele w.i Xiaolin Bai Lin Liu Feng Fu Jun wan College of Chemistry & Chemical Engineering Research Institute of Comprehensive Energy Industrial Technology Shaanxi Key Laboratory of Chemical Reaction Engineering Yan'an University Anhui Engineering Research Center of Carbon Neutrality College of Chemistry and Materials Science Anhui Normal University

The production of ultra-low sulfur clean fuels holds global significance for improving energy efficiency and reducing environmental pollution. Photocatalytic aerobic oxidative desulfurization（PODS） offers an attractive approach to efficiently remove refractory heterocyclic aromatic sulfur compounds under mild conditions. However, the sluggish charge dynamics,insufficient molecule activation, and slow mass transfer within photocatalysts restrict the overall desulfurization efficiency,hindering the widespread application of this technology. Herein, we developed a defective g-C3N4（M1U3CN） photocatalyst with bridged N3Cvacancies and hierarchical porous structures to address these limitations. This catalyst not only demonstrates outstanding dibenzothiophene（DBT） removal efficiency of 99.6% for model oil with high conversion and selectivity but also achieves complete sulfur removal from gasoline as well as 96.7% sulfur removal for distilled diesel at room temperature,successfully achieving ultradeep aerobic oxidative desulfurization. The introduction of rich N3Cvacancies and abundant micromeso-macroporous distribution in M1U3CN enhances kinetic efficiencies by promoting charge carrier separation, mass transfer,and molecular activation simultaneously; resulting in exceptional PODS performance. This work provides a collaborative strategy to overcome kinetic challenges in aerobic oxidative desulfurization via defect and structural engineering of the catalyst.

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Leader-follower: Human-centered intention-guided controller for novel SuperLimb with application to load-carrying scenarios

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Science China Technological Sciences 2025年第1期 325-338页

作者： Qinghua ZHANG Xianglong Li Hongw.i JiNG Kerui SUN Yuancheng Li Sikai ZHAO lele Li Haotian JU Ziqi wANG Rui wU Tianjiao ZHENG Jie ZHAO Yanhe ZHU The State Key Laboratory of Robotics and System Harbin Institute of Technology The Learning Algorithms and Systems Laboratory School of Engineeringécole Polytechnique Fédérale de Lausanne

Supernumerary robotic arms(SuperLimb) are a new type of wearable robot that works closely with humans as a third hand to augment human operation capability. Accurate conveyance of wearers' intentions, allocation of roles, and humancentered interaction considerations are the key points in the process of human–SuperLimb collaboration. This paper proposes a human-centered intention-guided leader–follower controller that relies on the dynamic modeling of SuperLimb with application to load-carrying scenarios. The proposed leader–follower controller takes the human as the leader and the SuperLimb as the follower, achieving effective information communication, autonomous coordination, and good force compliance between SuperLimb, humans, and the environment under human safety assurance. First, the human–SuperLimb dynamic system is modeled to achieve force interaction with the environment and wearer. Second, to achieve the precise intention extraction of humans, pose data from five visual odometry sensors are fused to capture the human state, the generalized position, the velocity of hands, and the surface electromyography signals from two myoelectric bracelets sensors are processed to recognize the natural hand gestures during load-carrying scenarios by a designed Swin transformer network. Then, based on the real-time distance detection between human and mechanical limbs, the security assurance and force-compliant interaction of the human–SuperLimb system are realized. Finally, the human hand muscle intention recognition, human–robot safety strategy verification,and comparative load-carrying experiments with and without the proposed method are conducted on the SuperLimb *** showed that the task parameters are well estimated to produce more reasonable planning trajectories, and SuperLimb could well understand the wearer's intentions to switch different SuperLimb actions. The proposed sensor-based human–robot communication framework motivates future studies of o

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Effectiveness and clinical benefit of a therapy of combined non-pharmaceutical Traditional Chinese Medicine for knee osteoarthritis: a randomized controlled study

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Journal of Traditional Chinese Medicine 2020年第3期40卷 447-454页

作者： Zhang lele Yuan Haixin Department of Traditional Chinese Medicine the First Affiliated Hospital of Henan University of Science and TechnologyClinical Medical College of Henan University of Science and TechnologyLuoyang 471003China

OBJECTiVE: To compare the efficacy of honey mouthwash 12.5% and chlorhexidine solution 0.2% to reduce the rate of oropharyngeal bacterial colonization in mechanically-ventilated ***: This study was a randomized, single blind, phase Ⅲ controlled clinical trial. Sixty patients newly admitted to internal and trauma intensive Care Units of the two educational hospitals of Sanandaj city affiliated with Kurdistan University of Medical Sciences were selected by convenience sampling and allocated to two groups of 30 patients using random blocks design. in each group,the mouthwash was applied twice a day for four consecutive days. Swab samples were taken from the mouth and throat of all patients three times a day(pre-intervention, two days, and four days after the intervention) and then the samples were transferred onto the blood agar and eosin methylene blue(EMB) culture plates and investigated for bacterial growth and colonization after 24-48 ***: The findings showed that oropharyngeal colonization was not significantly different between the two groups, pre-intervention, two days,and four days after the intervention(P > 0.05). Rinsing with honey mouthwash 12.5% led to the inhibition of Staphylococcus aureus and Pseudomonas aeruginosa on the fourth day of the intervention in all ***: None of the studied solutions contributed to the reduction of oropharyngeal bacterial colonization. it seems that the growth inhibition of Staphylococcus aureus and Pseudomonas aeruginosa by the honey 12.5% mouthwash in mechanically-ventilated patients need further investigation.

关键词： Osteoarthritis knee Electroacupuncture Pain measurement Needle warming moxibustion Teding Dianci Pu therapy Randomized controlled trail

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Coleman Automorphisms of Extensions of Finite Characteristically Simple Groups by Some Finite Groups

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Algebra Colloquium 2021年第4期28卷 561-568页

作者： Jinke Hai lele Zhao College of Mathematics and Statistics Qingdao University QingdaoShandong 266071China

Let G be an extension of a finite characteristically simple group by an abelian group or a finite simple *** is shown that every Coleman automorphism of G is an inner *** in such automorphisms arises from the study of... 详细信息

关键词： characteristically simple group Coleman automorphism normalizer property

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Numerical Analysis of Refueling Drogue Oscillation During Refueling Docking

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Transactions of Nanjing University of Aeronautics and Astronautics 2016年第2期33卷 173-179页

作者： Chen lele Liu Xueqiang College of Aerospace Engineering Nanjing University of Aeronautics and Astronautics Nanjing 210016 P. R. China

Refueling docking at different velocities is simulated by using computational fluid dynamics(CFD)*** Osher scheme and S-A turbulence model are used to solve the compressible Navier-Stokes equations,and the Delaunay mapping dynamic grid method is also *** the numerical results show that the velocity of refueling docking is very important for aerial *** the velocity is lower than 3m/s,the refueling drogue will move upward with obvious cycle staggering,w.ile moving upward with slight cycle staggering at the speed of3m/*** results can be referenced by aerial refueling design.

关键词： aerial refueling numerical simulation refueling drogue dynamic grid refueling docking

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inter-well internal resonance analysis of rectangular asymmetric cross-ply bistable composite laminated cantilever shell under transverse foundation excitation

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Applied Mathematics and Mechanics(English Edition) 2024年第8期45卷 1353-1370页

作者： lele REN w.i ZHANG Yufei ZHANG State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong UniversityShanghai 200240China Department of Mechanics Guangxi UniversityNanning 530004China Beijing Key Laboratory of Nonlinear Vibrations and Strength of Mechanical Structures College of Mechanical EngineeringBeijing University of TechnologyBeijing 100124China

The chaotic dynamic snap-through and complex nonlinear vibrations are investigated in a rectangular asymmetric cross-ply bistable composite laminated cantilever shell,in cases of 1:2 inter-well internal resonance and primary *** transverse foundation excitation is applied to the fixed end of the structure,and the other end is in a free *** first-order approximate multiple scales method is employed to perform the perturbation analysis on the dimensionless two-degree-of-freedom ordinary differential motion control *** four-dimensional averaged equations are derived in both polar and rectangular coordinate *** from the obtained frequency-amplitude and force-amplitude response curves,a detailed analysis is conducted to examine the impacts of excitation amplitude,damping coefficient,and tuning parameter on the nonlinear internal resonance characteristics of the *** nonlinear softening characteristic is exhibited in the upper stable-state,w.ile the lower stable-state demonstrates the softening and linearity *** simulation is carried out using the fourth-order Runge-Kutta method,and a series of nonlinear response curves are *** the excitation amplitude further elucidates the global bifurcation and chaotic dynamic snap-through characteristics of the bistable cantilever shell.

关键词： bistable composite laminated cantilever shell inter-well internal resonance primary resonance chaotic dynamic snap-through complex nonlinear vibration

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Precise regulation of intermembrane spacing with DNA nanojunctions for enhanced T-cell receptor triggering

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Science China Chemistry 2023年第8期66卷 2157-2159页

作者： lele Sun Zhuang Liu School of Life Sciences Shanghai UniversityShanghai200444China institute of Functional Nano&Soft Materials(FUNSOM) Jiangsu Key Lab Carbon Based Functional Materials and DevicesSoochow UniversitySuzhou215123China

it is well known that adaptive immunity involving T cells plays a crucial role in combating many diseases.T-cell activation is initiated by the engagement of T-cell receptors(TCRs)to peptide-loaded major histocompatibility complexes(p MHCs)on antigen-presenting cells(APCs),w.ich triggers a cascade of signaling events that ultimately lead to T-cell activation[1].

关键词： immunity spacing initiated

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Rare earth metals modified Ni-S2O8^2-/ZrO2-Al2O3 catalysts for n-pentane isomerization

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Chinese Journal of Chemical Engineering 2017年第1期25卷 74-78页

作者： Hua Song lele Zhao Na wang College of Chemistry ＆ Chemical Engineering Northeast Petroleum University Daqing 163318 China Provincial Key Laboratory of Oil ＆ Gas Chemical Technology College of Chemistry ＆ Chemical Engineering Northeast Petroleum University Daqing 163318 China

The effects of adding rare earth(RE) metals,such as Ce,Yb and Pr to Ni-S_2O_8^(2-)/ZrO_2-Al_2O_3(Ni-SZA) on the structure of catalysts as well as their isomerization performance were *** prepared catalysts were characterized by XRD,BET,FT-iR,Py-iR,and H_2-TPR,The results showed that the addition of RE metals can increase the strength and amounts of the acid sites,improve the redox properties of *** Yb-Ni-SZA catalyst showed the best redox properties,w.ich could provide enough metallic *** addition,it provided the largest amounts of weak and moderately strong acid *** RE metals modified Ni-SZA catalyst,Yb-Ni-SZA exhibited the highest isopentane yield of 61.7%at 160 °*** optimum isomerization catalytic performance of the catalysts decreased in the order of Yb-Ni-SZA > Pr-Ni-SZA > Ni-SZA > Ce-Ni-SZA.

关键词： Rare earths Solid superadd Catalyst Hydroisomerization

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Propagation of Rayleigh-type surface waves in a layered piezoelectric nanostructure with surface effects

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Applied Mathematics and Mechanics(English Edition) 2022年第3期43卷 327-340页

作者： lele ZHANG Jing ZHAO Guoquan NiE Jinxi LiU State Key Laboratory of Mechanical Behavior and System Safety of Tra±c Engineering Structures Shijiazhuang Tiedao UniversityShijiazhuang 050043China Hebei Key Laboratory of Mechanics of intelligent Materials and Structures Department of Engineering MechanicsShijiazhuang Tiedao UniversityShijiazhuang 050043China Department of Architecture Shijiazhuang Institute of Railway TechnologyShijiazhuang 050041China

This work investigates the dispersion properties of Rayleigh-type surface waves propagating in a layered piezoelectric nanostructure composed of a piezoelectric nanofilm over an elastic *** one of the most important features of nanostructures,surface effects characterized by surface stresses and surface electric displacements are taken into account through the surface piezoelectricity theory and the nonclassical mechanical and electrical boundary *** expressions of the dispersion equation are derived,and numerical results are provided to examine the effects of several surface-related parameters,including the surface elasticity,surface piezoelectricity,surface dielectricity,surface density,as well as surface residual stress,on the dispersion modes and phase *** size-dependent dispersion behaviors occurring with surface effects are also predicted,and they may vanish once the thickness of the piezoelectric nanofilm reaches a critical value.

关键词： surface effect surface piezoelectricity dispersion behavior piezoelectric nanofilm Rayleigh wave

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