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Pressure-induced emission in 0D metal halide(EATMP)SbBr5 by regulating exciton-phonon coupling

Chinese Journal of Structural Chemistry 2024年第7期43卷 47-53页

作者： Jiayuan Liang Xin Mi Songhao Guo Hui Luo Kejun Bu Tonghuan Fu Menglin Duan Yang Wang Qingyang Hu Rengen Xiong Peng Qin Fuqiang Huang Xujie Lü Center for High Pressure Science and Technology Advanced Research(HPSTAR) Shanghai201203China State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghai200050China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China Center of Micro-Nano System School of Information Science and TechnologyFudan UniversityShanghai200433China Ordered Matter Science Research Center Nanchang UniversityNanchang330031China State Key Lab of Metal Matrix Composites School of Materials Science and EngineeringShanghai Jiao Tong UniversityDongchuan Road 800Shanghai200240China Shanghai Key Laboratory of Material Frontiers Research in Extreme Environments(MFree) Shanghai Advanced Research in Physical Sciences(SHARPS)PudongShanghai201203China

Zero-dimensional(0D)hybrid metal halides are considered as promising light-emitting materials due to their unique broadband emission from self-trapped excitons(STEs).Despite substantial progress in the development of these materials,the photoluminescence quantum yields(PLQY)of hybrid Sb-Br analogs have not fully realized the ca-pabilities of these materials,necessitating a better fundamental understanding of the structure-property ***,we have achieved a pressure-induced emission in 0D(EATMP)SbBr5(EATMP=(2-aminoethyl)trimethylphosphanium)and the underlying mechanisms are investigated using in situ experimental characterization and first-principles *** pressure-induced reduction in the overlap between the STE states and ground states(GSs)results in the suppression of phonon-assisted non-radiative *** photoluminescence(PL)evo-lution is systematically demonstrated to be controlled by the pressure-regulated exciton-phonon coupling,which can be quantified using Huang-Rhys *** detailed studies of the S-PLQY relation in a series of 0D hybrid antimony halides,we establish a quantitative structure-property relationship that regulating S value toward 21 leads to the optimized *** work not only sheds light on pressure-induced emission in 0D hybrid metal halides but also provides valuable insights into the design principles for enhancing the PLQY in this class of materials.

关键词： 0D hybrid metal halides Pressure-induced emission Structure-property relationship Huang-Rhys factor Exciton-phonon coupling

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CSLP: Collaborative Solution to Long-Tail Problem and Popularity Bias in Sequential Recommendation

CSLP: Collaborative Solution to Long-Tail Problem and Popula...

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2024 IEEE International Conference on Systems, Man, and Cybernetics, SMC 2024

作者： Huang, Yan Yang, Zhenyu Hu, Wenyue Xu, Baojie Zhang, Zhibo Jinan250353 China Shandong Engineering Research Center of Big Data Applied Technology Faculty of Computer Science and Technology Jinan250353 China Shandong Provincial Key Laboratory of Computer Networks Shandong Fundamental Research Center for Computer Science Jinan250353 China

ISBN: (纸本)9781665410205

Sequential Recommender Systems (SRS), leveraging the temporal information from users' behaviors, have noticeably improved user experience against traditional systems. However, these behaviors often follow long-tail distribution, making the systems biased towards popular items (i.e., popularity bias). Moreover, popularity bias would amplify the neglect of long-tail recommendations, thereby sharpening the long-tail problem. Previous researches usually address these challenges independently, focusing on reducing the over-recommendation of popular items or enhancing the representation quality of tail items. Indeed, it is possible to incorporate their merits to achieve the best of both worlds. Thus, we propose a novel and unified framework, named Collaborative Solution to Long tailed problem and Popularity bias (CSLP), to tackle both the long-tail problem and popularity bias simultaneously. To achieve this, we first introduce a representation enhancement module featuring dual generators to enhance user and item representations, particularly for those in the tail. On the other hand, a debiasing module incorporating an Inverse Propensity Score (IPS) with a clipping strategy is introduced to further alleviate the popularity bias. Specifically, this clipping strategy demonstrates a clear decrease in the original IPS method's variance, effectively improving the recommendation for stability and accuracy. Experiments on three widely-used datasets show CSLP's effectiveness in solving both issues. CSLP surpasses all baselines (traditional, popularity bias, and long-tail problem) in overall performance, significantly enhancing recommendation accuracy for both tail users and items, and achieving a more balanced ratio of recommendations between popular and tail items. Code is available at https://***/Echohuangyan/CSLP. © 2024 IEEE.

关键词： Inverse problems

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Enhanced Fatigue Properties of 2219 Al Alloy Joints via Bobbin Tool Friction Stir Welding

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Acta Metallurgica Sinica(English Letters) 2023年第4期36卷 586-596页

作者： Zhenlin Wang Beibei Wang Zhen Zhang Peng Xue Yunfei Hao Yanhua Zhao Dingrui Ni Guoqing Wang Zongyi Ma 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 ChinaShenyang 110016China China Academy of Launch Vehicle Technology Beijing 100076China Capital Aerospace Machinery Company Beijing 100076China

In the present study,2219-T87 Al alloy plates,4 mm in thickness,were subjected to bobbin tool friction stir welding(BTFSW)under relatively high welding speeds of 200 and 400 mm/min,with the aim to analyze the effect of welding speeds on fatigue properties of the *** results showed that the tension–tension high-cycle fatigue performance of the BT-FSW joints at room temperature was significantly enhanced compared to that of other joints of 2xxx series Al alloys *** at a high welding speed of 400 mm/min,the fatigue strength of the joint reached 78%of the base material together with a high tensile strength of 311 *** was found that the joint line remnants had no effects on the fatigue properties of the BT-FSW joints due to the elimination of root flaws under the action of the lower *** of the samples with the welding speed of 200 mm/min failed at the thermo-mechanical zone(TMAZ)during fatigue tests,attributable to the coarsened grains and precipitates,but all of the samples with high welding speed of 400 mm/min randomly failed at the nugget zone due to the improved hardness value in the TMAZ.

关键词： 2219 Al alloys Bobbin tool friction stir welding Microstructure Fatigue properties

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Simultaneous achievement of large electrocaloric effect and ultrawide operating temperature range in BaTiO_(3)-based lead-free ceramic

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Journal of advanced Ceramics 2024年第8期13卷 1234-1241页

作者： Zhaojie Wang Yingzhi Meng Silin Tang Xiang Niu Hongfang Zhang Dingyuan Wang Yisong Bai Bialin Peng Xue Chen Qingqing Ke Sheng-Guo Lu Laijun Liu Guangxi Key Lab of Optical and Electronic Functional Materials and Devices Collaborative Innovation Center for Exploration of Nonferrous Metal Deposits and Efficient Utilization of ResourcesCollege of Materials Science and EngineeringGuilin University of TechnologyGuilin 541004China School of Microelectronics Science and Technology Sun Yat-sen UniversityZhuhai 519082China Guangdong Provincial Research Center on Smart Materials and Energy Conversion Devices School of Materials and EnergyGuangdong University of TechnologyGuangzhou 510006China School of Physical Science and Technology&Key Laboratory of Advanced Electrode Materials for Novel Solar Cells for Petroleum and Chemical Industry of China Suzhou University of Science and TechnologySuzhou 215009China Qingdao Haier Smart Technology R&D Co. Ltd.Qingdao 266100China School of Advanced Materials and Nanotechnology Xidian UniversityXi'an 710071China Guangxi Key Laboratory of Manufacturing System&Advanced Manufacturing Technology Guilin University of Electronic TechnologyGuilin 541004China

The electrocaloric effect(ECE),known for its environmentally friendly characteristics,holds significant promise for advancing next-generation solid-state refrigeration *** a large ECE along with a wide working temperature range near room temperature remains a key developmental *** this study,we successfully obtained a substantial ECE of 1.78 K and an extensive working temperature range of 103 K(AT>1.52 K)near room temperature in CaZrO_(3)-modified BaTiO_(3) lead-free ferroelectric ***,this achievement was verified using direct *** piezoresponse force microscopy(PFM)results suggest that the broad temperature range is attributed to the formation of ferroelectric microdomains and polar nanoregions(PNRs).Furthermore,X-ray photoelectron spectroscopy(XPS)and ultraviolet-visible(UV-Vis)spectroscopy reveal a decrease in the oxygen vacancy concentration and an increase in the bandgap for higher CaZrO_(3) doping *** changes synergistically enhance the maximum applied electric field,helping to achieve a high-performance EcE near room *** research presents a straightforward and effective approach for achieving high-performance ECEs in BaTiOg lead-free ceramics,offering promising prospects for application in next-generation solid-state refrigeration technologies.

关键词： BaTiO_(3) electrocaloric effect oxygen vacancy band-gap

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Hantzsch Ester Modified Asymmetric BODIPY Probe with Ultra-high Sensitivity for Ultra-fast Detection of Endogenous Hypochlorite in Living Cells

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Chinese Journal of Chemistry 2023年第23期41卷 3319-3325页

作者： Tianli Zhu Mengting Zhao Rongcheng Wang Chenjun Dong Xuemei Dong Jie Sun Lixin Sun Chunchang Zhao Key Laboratory for Advanced Materials and Feringa Nobel Prize Scientist Joint Research Center Institute of Fine ChemicalsSchool of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai200237 China

Hypochlorite(ClO^(-))is an important reactive oxygen species produced by the immune system to fight off invading pathogens,but its over-expression can interfere with normal physiological process and induce serious *** a variety of molecular probes have been reported for detecting ClO^(-),the development of advanced fluorescent tools with faster response and higher sensitivity to precisely monitor ClO^(-)remains a *** this work,two Hantzsch ester(a derivative of 1,4-dihydropyridine)derived fluorescent probes MeDHP-BCl and MeDHP-PhBCl were constructed based on asymmetric *** probes exhibit significant fluorescence turn-on in the ultra-sensitive(detection limit<1 nmol/L)and ultra-fast response(≤5 s)to ClO^(-).The reaction has been determined to be a highly selective N-chlorination of Hantzsch ester which cannot be activated by various common bioactive species,including nitric oxide(NO)that could oxidize Hantzsch ester under aerobic physiological conditions in most ***-PhBCl possessed a relatively longer fluorescence emission wavelength and higher quantum yield after activation,while more notably,MeDHP-BCl displayed lower cytotoxicity and more remarkable fluorescence increment in the response to ClO^(-),enabling selective and precise visualization of endogenous ClO^(-)over-expression in living RAW264.7 cells.

关键词： Hypochlorite Hantzsch ester BODIPY Fluorescent probes Fluorescence spectroscopy Biomarkers Biosensors Bioimaging

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Recent advances in metal-loaded MOFs photocatalysts:From single atom,cluster to nanoparticle

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Chinese Chemical Letters 2025年第1期36卷 68-79页

作者： Shenglan Zhou Haijian Li Hongyi Gao Ang Li Tian Li Shanshan Cheng Jingjing Wang Jitti Kasemchainan Jianhua Yi Fengqi Zhao Wengang Qu Advanced Innovation Center for Materials Genome Engineering Beijing Key Laboratory of Function Materials for Molecule&Structure ConstructionSchool of Materials Science and EngineeringUniversity of Science and Technology BeijingBeijing 100083China National Key Laboratory of Energetic Materials Xi’an Modern Chemistry Research InstituteXi’an 710065China Shunde Innovation School University of Science and Technology BeijingShunde 528399China School of Materials Science and Engineering Suzhou University of Science and TechnologySuzhou 215009China Department of Chemical Technology Chulalongkorn UniversityBangkok 10330Thailand

Photocatalysis is widely regarded as a highly promising sustainable technique for addressing the challenges posed by environmental pollution and energy *** recent years,metal-loaded MOFs has become a rising star within the domain of photocatalysis due to its high specific surface area and porosity,adjustable structure,diverse and abundant catalytic components,which has exhibited excellent photocatalytic activity and exhibit great potential in a range of *** this paper,the principles for evaluating the photocatalytic performance of MOFs-based materials were firstly introduced,and some typical examples were also listed *** with this,particular emphasis is paid to the main factors affecting the photocatalytic performance of metal-loaded *** the synthesis and design strategies of MOFs loaded metal entities of varying sizes(single atoms,nanoclusters,and nanoparticles),and their applications in photocatalytic CO_(2)reduction,hydrogen production,photooxidation and photocatalytic hydrogenation were summarized and ***,the opportunities and challenges faced in this kind of MOFs-based composites were analyzed from different *** report is expected to help researchers design and develop high-performance MOFs-based photocatalytic materials.

关键词： Metal-loaded MOFs Photocatalysis Single atom catalysts Nanoclusters Nanoparticles

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Corrosion behavior of single-and poly-crystalline dual-phase TiAl–Ti3Al alloy in NaCl solution

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International Journal of Minerals,Metallurgy and Materials 2023年第4期30卷 689-696页

作者： Dongpeng Wang Guang Chen Anding Wang Yuxin Wang Yanxin Qiao Zhenguang Liu Zhixiang Qi Chain Tsuan Liu School of Materials Science and Engineering Jiangsu University of Science and TechnologyZhenjiang 212100China Centre for Advanced Structural Materials Department of Mechanical and Biomechanical EngineeringCity University of Hong KongHong Kong 999077China Engineering Research Center of Materials Behavior and Design Ministry of EducationNanjing University of Science and TechnologyNanjing 210094China School of Materials Science and Engineering Dongguan University of TechnologyDongguan 523808China

To clarify the correlation of single-crystalline structure with corrosion performance in high-strength TiAl alloys, electrochemical and surface characterization was performed by comparing Ti–45Al–8Nb dual-phase single crystals with their polycrystalline counterparts in NaCl solution. Polarization curves show a lower corrosion rate and a higher pitting potential of ~280 mV for the dual-phase single crystals. Electrochemical impedance spectroscopy and potentiostatic polarization plots revealed a higher impedance of the charge transfer through the compact passive film. Surface composition analysis indicated a compact film with more content of Nb, as twice as that in the film on the *** results reflect that the dual-phase Ti–45Al–8Nb single crystals possess a higher corrosion resistance in NaCl solution, compared with their polycrystalline counterpart, arising from a more homogeneous microstructure and composition distribution.

关键词： titanium alloy single crystal corrosion X-ray photoelectron spectroscopy

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Metalphthalocyanine frameworks grown on TiO_(2)nanotubes for synergistically and efficiently electrocatalyzing urea production from CO_(2)and nitrate

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science China Chemistry 2023年第5期66卷 1417-1424页

作者： Ning Li Hui Gao Zhixin Liu Qianjun Zhi Bowen Li Lei Gong Baotong Chen Tao Yang Kang Wang Peng Jin Jianzhuang Jiang Beijing Advanced Innovation Center for Materials Genome Engineering Beijing Key Laboratory for Science and Application of Functional Molecular and Crystalline MaterialsDepartment of Chemistry and Chemical EngineeringSchool of Chemistry and Biological EngineeringUniversity of Science and Technology BeijingBeijing 100083China School of Materials Science and Engineering Hebei University of TechnologyTianjin 300130China Innovation Research Institute for Carbon Neutrality University of Science and Technology BeijingBeijing 100083China

Electrocatalytic synthesis of urea from CO_(2)and NO_(3)^(-)under ambient conditions provides an appealing alternative to the traditional energy-intensive urea synthetic *** active and selective electrocatalysts for efficient urea production are therefore urgently desired owing to the unsatisfactory performance of the thus far reported ***,a phthalocyaninebased(Pc-based)covalent organic framework(COF),namely Co Pc-COF,fabricated from the nucleophilic substitution reaction of hexadecafluorophthalocyaninato cobalt with octahydroxylphthalocyanine cobalt,in situ grew on the surface of multilayered Ti O_(2)nanotubes(NTs),generating the Co Pc-COF@Ti O_(2)NTs *** X-ray diffraction analysis in combination with electron microscopy measurements discloses the uniform coating of crystalline Co Pc-COF on the multilayered Ti O_(2)NTs in Co Pc-COF@Ti O_(2)***,electrochemical tests reveal the superior electrocatalytic activity of Co Pc-COF@Ti O_(2)NTs towards urea production from CO_(2)and NO3-with a record-high yield of 1,205μg h^(-1)cm^(-2)and an outstanding Faraday efficiency of 49%at-0.6 V versus reversible hydrogen electrode due to the significant synergistic catalysis *** situ attenuated total reflection infrared spectroscopic investigation and theoretical calculations unveil the efficient C–N coupling reaction between*CO intermediate derived from CO_(2)on Co Pc moieties and*NH2intermediate formed from NO_(3)^(-)on Ti O_(2)NTs during the urea formation process over Co Pc-COF@Ti O_(2)*** work should be helpful towards designing and fabricating high-performance electrocatalysts for sustainable synthesis of urea through efficient synergistic effect of multiactive centers.

关键词： covalent organic frameworks phthalocyanine TiO_(2) electrocatalytic urea synthesis C–N bond coupling

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Near-infrared long-lifetime emission via triplet-to-singlet F?rster resonance energy transfer

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Green Chemical Engineering 2025年第1期6卷 1-5页

作者： Ruihong Liu Dongzhi Liu Xiang Ma Institute of Functional Nano&Soft Materials(FUNSOM) Jiangsu Key Laboratory for Carbon-Based Functional Materials&DevicesSoochow UniversitySuzhou215123China School of Chemical Engineering and Technology Collaborative Innovation Center of Chemical Science and EngineeringTianjin Engineering Research Center of Functional Fine ChemicalsTianjin UniversityTianjin300072China Key Laboratory for Advanced Materials and Feringa Nobel Prize Scientist Joint Research Center Frontiers Science Center for Materiobiology and Dynamic ChemistrySchool of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai200237China

Here,an innovative approach to achieve near-infrared(NIR)long-lived circularly polarized luminescence(CPL)in amorphous organic polymer materials was *** co-doping bi-naphthalene derivative R/S-BPN as energy donors with porphyrin derivative TPPOH as energy acceptor into PVA polymer matrix,the NIR long-lifetime fluorescence was successfully realized through the principles of triplet-to-singlet F?rster resonance energy transfer(TS-FRET).Photophysical characterizations revealed distinct room temperature phosphorescence(RTP)emission peaks and phosphorescence lifetimes for different donor-acceptor *** TS-FRET process facilitated extended lifetime and red-shifted emission of the acceptor ***,employing the chiral donor R/S-BPN as chiral seeds to establish chiral environments facilitated the achievement of near-infrared *** findings offer a novel and practical strategy for achieving long-wavelength and long-lifetime CPL fluorescence without complex molecular engineering,presenting potential applications in various technological fields.

关键词： Room temperature phosphorescence Circularly polarized luminescence Forster resonance energy transfer

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Tiltwing Transition Flight Analysis Using High-Fidelity CFD 80

Tiltwing Transition Flight Analysis Using High-Fidelity CFD

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80th Annual Vertical Flight Society Forum and technology Display, FORUM 2024

作者： Perez, David Garcia Diaz, Patricia Ventura Sanguinetti, Anthony Yoon, Seokkwan Science and Technology Corporation NASA Ames Research Center Moffett FieldCA United States NASA Advanced Supercomputing Division NASA Ames Research Center Moffett FieldCA United States

ISBN: (纸本)9781713897941

Transition from hover to forward flight and vice versa represents the most critical flight phase of tiltwing aircraft. Despite its importance to ensure a safe operation, the aerodynamics of this maneuver are not sufficiently understood. This paper focuses on the study of transition flight for NASA's six-passenger tiltwing air taxi by means of high-fidelity computational fluid dynamics simulations. On the basis of a static trim solution, four points within the transition corridor are analyzed: transition mode at wing tilt angles of 60◦ and 44◦, and airplane mode at airspeeds of 110 kt and 155 kt. We investigate the balance of forces and moments for rotor-borne and wing-borne regimes, and how rotor-on-rotor and rotor-on-wing interactions affect performance. The simulations indicate that during the early stages of transition, the vortices remain in close proximity to the proprotors, inducing large fluctuations on the order of the mean blade loading. Additionally, the blowing and swirling effects of the proprotor wakes delay flow separation over a portion of the wing. The mid-transition conditions appear to be critical, with extensive regions of separated flow over the wing. In airplane mode, proprotor-wing slipstream effects can be exploited to enhance lift generation. The results of this paper contribute to a deeper understanding of the complex aerodynamic interactions during transition flight to enable a safer and more efficient operation of tiltwing aircraft. Copyright © 2024 by the Vertical Flight Society. All rights reserved.

关键词： Wings

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