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Rare Metals 2024年第4期43卷 1702-1712页

作者： Xuan Liu Zi-Xia Lin Yin-Biao Shi Xiao-Yan Wang Ming-Ye Ding Xiao-Fei Yang College of science Nanjing Forestry UniversityNanjing210037China Testing Center Yangzhou UniversityYangzhou225009China

Regulating luminescent dynamics of lanthanide-based luminescent materials via external stimuli is of great significance in the fields of optical thermometry and high-level ***,it is still a huge challenge to realize multimodal emissions with tunable color outputs from a single activator in simple structures via smart dynamic control of photon transition ***,we present a mechanistic strategy to achieve multimodal luminescence of Er^(3+)activators with color-switchable outputs in a non-core-shell *** the control of excitation dynamics(λ_(ex)=980,808,1532,377 nm),the population among the intermediate en ergy levels of Er^(3+)and the interaction between Er^(3+)and Yb^(3+)could be precisely modulated through energy transfer and migration processes,leading to the generation of colortunable multimodal luminescence upon diverse excitation modes(non-steady-state,single-/dual-wavelength steady,thermal activation).Inspired by its special luminescent performance,the as-obtained material exhibits great potential in noncontact thermometry,multimodal anticounterfeiting,and high-capacity information encryption by performing a series of proof-of-concept *** findings might provide a conceptual model to modulate the luminescent dynamics in a simple-structured system for the generation of color-adjustable multimodal emissions,which is convenient for the development of advanced luminescent materials toward versatile cuttingedge applications.

关键词： Lanthanide ions Multimodal emission Upconversion Downshifting Anti-counterfeiting Luminescent thermometry

Resource allocation for D2D-assisted haptic communications

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Digital Communications and Networks 2024年第1期10卷 63-74页

作者： Yan Wu Chao Yue Yang Yang Liang Ao College of Telecommunication Engineering Army Engineering University of PLANanjing210000China

Haptic communications is recognized as a promising enabler of extensive services by enabling real-time haptic control and feedback in remote environments,e.g.,teleoperation and autonomous *** the strict transmission requirements on reliability and latency,Device-to-Device(D2D)communications is introduced to assist haptic *** particular,the teleoperators with poor channel quality are assisted by auxiliaries,and each auxiliary and its corresponding teleoperator constitute a D2D ***,the haptic interaction and the scarcity of radio resources pose severe challenges to the resource allocation,especially facing the sporadic packet ***,the contentionbased access scheme is applied to achieve low-latency transmission,where the resource scheduling latency is omitted and users can directly access available *** this context,we derive the reliability index of D2D pairs under the contention-based access scheme,i.e.,closed-loop packet error ***,the reliability performance is guaranteed by bidirectional power control,which aims to minimize the sum packet error probability of all D2D *** game theory is introduced to solve the problem with low ***,a distributed power control algorithm based on synchronous log-linear learning is proposed to converge to the optimal Nash *** results demonstrate the superiority of the proposed learning algorithm.

关键词： Haptic communications D2D Power control Contention-based access Potential game

Multiscale causes of the 2022 Yangtze mega-flash drought under climate change

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science China Earth sciences 2024年第8期67卷 2649-2660页

作者： Xing YUAN Yumiao WANG Shiyu ZHOU Hua LI Chenyuan LI School of Hydrology and Water Resources Nanjing University of Information Science and TechnologyNanjing 210044China Institute of Atmospheric Physics Chinese Academy of SciencesBeijing 100029China Key Laboratory of Hydrometeorological Disaster Mechanism and Warning of Ministry of Water Resources Nanjing University of Information Science and TechnologyNanjing 210044China

The 2022 Yangtze mega-flash drought is characterized by strong intensity and rapid development both in time and space,accompanied by a persistent anticyclonic circulation ***,the causes of the extreme event remain elusive given the multiscale nature of *** we presented a brief overview for the oceanic and terrestrial causes of the megaflash drought during the summer of 2022,and estimated the risk in a changing *** the soil moisture percentile as the drought index,it was found that the drought expanded to the entire Yangtze River basin within two months,with 80%of basin under severe drought conditions at the end of *** the intensity and onset speed of the 2022 mega-flash drought were ranked as the first during the past 62 years,with return periods of 86 and 259 years,*** results of composite analysis showed that the spring La Ni?a can facilitate the abrupt change from a wet/normal condition in May–June to drought in July–August over the Yangtze River basin,which was beneficial for the increase of flash drought intensity and onset speed *** analysis through the linear regression also indicated that the unprecedented intensity was associated with the negative phase of the Pacific Decadal *** by a coupling strength index for soil moisture and vapor pressure deficit,it was found that there was a strong land-atmosphere coupling over the Yangtze River basin during July–August *** attribution by using CMIP6 climate models suggested that land-atmosphere coupling increased the risks of flash drought intensity and onset speed like 2022 by 61%±6%and 64%±7%under natural climate forcings,and the synergy of coupling and anthropogenic climate change would increase the risks by 75%±22%and 85%±12%.Our findings emphasized the role of landatmosphere coupling combined with anthropogenic climate change in intensifying flash droughts.

关键词： Flash drought Yangtze River basin Land-atmosphere coupling Climate change Attribution

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Photothermal catalytic C-C coupling to ethylene from CO_(2) with high efficiency by synergistic cooperation of oxygen vacancy and half-metallic WTe_(2)

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Journal of Energy Chemistry 2024年第6期93卷 547-556,I0014页

作者： Xiaoyue Zhang Yong Yang Yingjie Hu Lijun Xiong Tianyu Wang Panjie Li Jinyou Shen Key Laboratory of Environmental Remediation and Ecological Health Ministry of Industry and Information TechnologySchool of Environmental and Biological EngineeringNanjing University of Science and TechnologyNanjing 210094JiangsuChina School of Chemistry and Chemical Engineering Nanjing University of Science and TechnologyNanjing 210094JiangsuChina Nanjing Key Laboratory of Advanced Functional Materials Nanjing Xiaozhuang UniversityNanjing 210094JiangsuChina jiangsu Environmental Engineering Technology Co.Ltd Nanjing 210019JiangsuChina

Photothermal catalytic CO_(2) conversion provides an effective solution targeting carbon neutrality by synergistic utilization of photon and ***,the C-C coupling initiated by photothermal catalysis is still a big ***,a three-dimensional(3D)hierarchical W_(18)O_(49)/WTe_(2) hollow nanosphere is constructed through in-situ embodying of oxygen vacancy and tellurium on the scaffold of WO_(3).The light absorption towards near-infrared spectral region and CO_(2) adsorption are enhanced by the formation of half-metal WTe_(2) and the unique hierarchical hollow *** with the generation of oxygen vacancy with strengthened CO_(2) capture,the photothermal effect on the samples can be sufficiently exploited for activating the CO_(2) *** particular,the close contact between W_(18)O_(49)and WTe_(2) largely promotes the photoinduced charge separation and mass transfer,and thus the~*CHO intermediate formation and fixedness are *** a result,the C-C coupling can be evoked between tungsten and tellurium atoms on WTe_(2).The ethylene production by optimized W_(18)O_(49)/WTe_(2) reaches 147.6μmol g^(-1)with the selectivity of 80%.The in-situ diffuse reflectance infrared Fourier transform spectroscopy(DRIFTS)and density functional theory(DFT)calculations are performed to unveil the presence and significance of aldehyde intermediate groups in C-C *** half-metallic WTe_(2) cocatalyst proposes a new approach for efficient CO_(2) conversion with solar energy,and may especially create a new platform for the generation of multi-carbon products.

关键词： Photothermal catalysis Half-metal WTe_(2) C–C coupling Carbon neutrality

Electrically tunable phase-change metasurface for dynamic infrared thermal camouflage

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Photonics Research 2024年第2期12卷 292-300页

作者： YUFENG XIONG YUNZHENG WANG CHAO FENG YAOLAN TIAN LIANG GAO JUN-LEI WANG ZHUANG ZHUO XIAN ZHAO Center for Optics Research and Engineering Key Laboratory of Laser&Infrared SystemMinistry of EducationShandong UniversityQingdao 266237China School of Information science and Engineering Shandong UniversityQingdao 266237China

Dynamic infrared thermal camouflage technology has attracted extensive attention due to its ability to thermally conceal targets in various environmental backgrounds by tuning thermal *** use of phase change materials(PCMs)offers numerous advantages,including zero static power,rapid modulation rate,and large emissivity tuning ***,existing PCM solutions still encounter several practical application challenges,such as temperature uniformity,amorphization achievement,and adaptability to different *** this paper,we present the design of an electrically controlled metal-insulator-metal thermal emitter based on a PCM metasurface,and numerically investigate its emissivity tunability,physical mechanisms,heat conduction,and thermal camouflage performance across different ***,the influence of the quench rate on amorphization was studied to provide a guidance for evaluating and optimizing device *** results reveal that the thermal emitter exhibits a wide spectral emissivity tuning range between 8 and 14μm,considerable quench rates for achieving amorphization,and the ability to provide thermal camouflage across a wide background temperature ***,it is anticipated that this contribution will promote the development of PCM-based thermal emitters for practical dynamic infrared thermal camouflage technology with broad applications in both civilian and military domains.

关键词： thermal dynamic phase

Constructing Al@C-Sn pellet anode without passivation layer for lithium-ion battery

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International Journal of Minerals,Metallurgy and Materials 2024年第3期31卷 552-561页

作者： Kangzhe Cao Sitian Wang Yanan He Jiahui Ma Ziwei Yue Huiqiao Liu College of Chemistry and Chemical Engineering Xinyang Normal UniversityXinyang 464000China Xinyang Key Laboratory of Low-Carbon Energy Materials Xinyang 464000China Henan province Key Laboratory of Utilization of Non-Metallic Mineral in the South of Henan Xinyang 464000China

Al is considered as a promising lithium-ion battery(LIBs)anode materials owing to its high theoretical capacity and appropri-ate lithation/de-lithation ***,its inevitable volume expansion causes the electrode structure instability,leading to poor cyclic ***’s worse,the natural Al2O3 layer on commercial Al pellets is always existed as a robust insulating barrier for elec-trons,which brings the voltage dip and results in low reversible ***,this work synthesized core-shell Al@C-Sn pellets for LIBs by a plus-minus *** this proposal,the natural Al2O3 passivation layer is eliminated when annealing the pre-introduced SnCl2,meanwhile,polydopamine-derived carbon is introduced as dual functional shell to liberate the fresh Al core from re-oxidization and alle-viate the volume *** from the addition of C-Sn shell and the elimination of the Al2O3 passivation layer,the as-prepared Al@C-Sn pellet electrode exhibits little voltage dip and delivers a reversible capacity of 1018.7 mAh·g^(-1) at 0.1 A·g^(-1) and 295.0 mAh·g^(-1) at 2.0 A·g^(-1)(after 1000 cycles),***,its diffusion-controlled capacity is muchly improved compared to those of its counterparts,confirming the well-designed nanostructure contributes to the rapid Li-ion diffusion and further enhances the lithium storage activity.

关键词： lithium-ion battery high-performance anode aluminum passivation layer plus-minus strategy

Work-function-induced interfacial electron redistribution of MoO_(2)/WO_(2) heterostructures for high-efficiency electrocatalytic hydrogen evolution reaction

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Rare Metals 2024年第2期43卷 489-499页

作者： Tong-Fei Li Jing Li Lu-Ping Zhang Jia-Wei Ke Meng-Xing Fan Li-Fang Zhang Cheng-Wei Deng Yi Sun Tao Qian Cheng-Lin Yan School of Chemistry and Chemical Engineering Nantong UniversityNantong226019China jiangsu Key Laboratory of New Power Batteries Jiangsu Collaborative Innovation Centre of Biomedical Functional MaterialsSchool of Chemistry and Materials ScienceNanjing Normal UniversityNanjing210023China Aerospace Hydrogen Energy Technology(Shanghai)Co.Ltd. Shanghai201800China Key Laboratory of Core Technology of High Specific Energy Battery and Key Materials for Petroleum and Chemical Industry College of EnergySoochow UniversitySuzhou215006China Light Industry Institute of Electrochemical Power Sources Suzhou215006China

The engineering of the electronic configurations of active sites,together with the production of more accessible active sites through heterostructure design,has been established as a forceful methodology for boosting water electrolysis ***,a facile approach is developed to fabricate well-dispersed MoO_(2) and WO_(2) nanoparticles with abundant heterointerfaces entrapped in N,P-doped carbon nanofibers(referred to as MoO_(2)/WO_(2)@N,P-CNFs hereafter)as hydrogen evolution reaction(HER)electrocatalysts in alkaline and acidic *** spectroscopic analyses and theoretical findings manifest that the heterointerface formed by the work function modulation of MoO_(2)/WO_(2) triggers the spontaneous electron redistribution from MoO_(2)to WO_(2) and a built-in electric field,which is essential to promote water adsorption,optimize the H-intermediate adsorption energy,result in the enhanced charge transfer efficiency,and ultimately increase the intrinsic HER ***,the intimate confinement of MoO_(2)/WO_(2) heterostructures in the porous carbon substrate can restrain the active sites from unfavorable coarsening and detachment,thus ensuring facilitated HER kinetics and outstanding structural *** a result,MoO_(2)/WO_(2)@N,P-CNFs exhibit superior catalytic HER performance in acidic and basic solutions,requiring 118 and 95 mV overpotentials to achieve 10 mA·cm^(−2),respectively,surpassing a number of reported non-noble metal-based *** work provides guidelines for the rational design and construction of special metallic heterocomponents with optimized interfacial electronic structure for various electrochemical technologies.

关键词： Electrospinning MoO_(2)/WO_(2) heterostructure Work function Hydrogen evolution reaction

Online preparation of high-quality BN coatings with atomic diffusion based on carbon-free water-soluble precursor

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Journal of Advanced Ceramics 2024年第3期13卷 272-281页

作者： Yiang Du Bing Wang Yunbo Zhang Quzhi Song Fuwen Wang Cheng Han Xiaoshan Zhang Yingde Wang science and Technology on Advanced Ceramic Fibers and Composites Laboratory College of Aerospace Science and EngineeringNational University of Defense TechnologyChangsha 410073China

Efficient and environmentally friendly production of high-quality continuous fiber coatings using current preparation methods is highly challenging due to issues such as scale and batch processing restrictions,low deposition rate,high energy consumption,and utilization of multiple environmentally hazardous *** address these challenges,we propose a stable and efficient wet chemical deposition coating method for high-throughput online continuous preparation of boron nitride(BN)coatings on ceramic fibers under an ambient *** process involves surface modification,in-situ wet chemical deposition,and heat treatment,and all seamlessly connecting with the ceramic fiber preparation process through continuous *** groups were introduced via surface modification enhancing wettability of the fiber surface with impregnating *** in-situ reaction and atom migration improve uniformity and binding of the *** a result,outstanding impregnation and adhesion properties are achieved.A comprehensive analysis to evaluate the impact of the BN coatings was conducted,which demonstrates that the BN-coated fibers exhibit a remarkable 36%increase in tensile strength,a 133%increase in fracture toughness,and enhanced temperature resistance of up to 1600℃.It provides a secure and efficient platform for cost-effective production of functional and high-quality coatings through targeted surface modification and rapid stretching impregnation.

关键词： polymer-derived ceramics SiC fibers wet chemical deposition atomic diffusion boron nitride(BN)coatings

Robust enhancement of valley polarization and quantum yield in composition grading lateral heterostructure of MoS2-WS2 monolayer

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Progress in natural science:Materials International 2024年第1期34卷 187-193页

作者： Mengke Kang Cheng Zhang Congpu Mu Kun Zhai Tianyu Xue Bochong Wang Fusheng Wen Yingchun Cheng Jianyong Xiang Jun-Feng Dai Anmin Nie Zhongyuan Liu Center for High Pressure science State Key Laboratory of Metastable Materials Science and Technology Yanshan University Shenzhen Institute for Quantum science and Engineering and Department of Physics Southern University of Science and Technology Shenzhen Key Laboratory of Quantum science and Engineering

Valley degeneracy can be broken owing to the strong spin-orbit coupling in two-dimensional transition metal dichalcogenides（2D-TMDCs）. Valley-dependent interaction of carriers in TMDCs with different circular polarizations of light offers valley degree-of-freedom besides charge and spin to carry information. Thus, bandgap engineering of 2D-TMDCs plays a critical role in developing practical valleytronic devices. Hereby, we demonstrate a great enhancement in quantum yield as well as polarization of monolayer MoS2achieved by gradually alloying W atoms in MoS2. By appropriately setting a time offset between the evaporation of MoO3and WO3precursors during chemical vapor deposition, a compositionally graded heterostructure of MoS2-WS2monolayer can be readily grown at large scale. Raman and transmission electron microscopy measurements demonstrate that the interface possesses a steep gradient in composition, spanning from MoS2to WS2over a length ～2 μ*** to pure monolayer MoS2, the photoluminescence intensity at the compositionally graded interface of Mo1-xWxS2was observed to increase by a factor of 16 owing to the effective separation of photogenerated carriers by the built-in electric field. Particularly, a remarkably high polarization of 70% at 16 K is demonstrated for the compositionally graded interface of Mo1-xWxS2, which is ～1.4 times larger than that in MoS2and is attributed to the combined effect of the alloyed structure and graded bandgap. Such an engineering scheme with a graded bandgap offers new approach for the development of high-efficiency valleytronics devices.

关键词： Transition metal dichalcognide monolayer Compositionally graded in-plane heterostructure Chemical vapor deposition Valley polarization Quantum yield

Tailored heterostructured Ni_(3)N-NiO nano-frameworks for boosting electrocatalytic oxygen evolution via surface-modulated plasma strategy

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Nano Research 2024年第9期17卷 7909-7917页

作者： Bo Ouyang Haonan Qin Chao Sun Yilin Deng Ang Li Jipeng Zhu Erjun Kan Rajdeep Singh Rawat MIIT Key Laboratory of Semiconductor Microstructure and Quantum Sensing School of ScienceNanjing University of Science&TechnologyNanjing 210094China The Laboratory of Road and Bridge Civil EngineeringSchool of ScienceNanjing University of Science&TechnologyNanjing 210094China Institute for Energy Research Jiangsu UniversityZhenjiang 212013China natural sciences and science Education National Institute of EducationNanyang Technological University637616Singapore

The facile reconfiguration of phases plays a pivotal role in enhancing the electrocatalytic production of H2 through heterostructure *** chemical methods have been explored extensively for this purpose,plasma-based techniques offer a promising avenue for achieving heterostructured ***,the conventional plasma approach introduces complexities,leading to a multi-step fabrication process and challenges in precisely controlling partial surface structure modulation due to the intricate interaction *** our pursuit of heterostructures with optimized oxygen evolution reaction(OER)behavior,we have designed a facile auxiliary insulator-confined plasma system to directly attain a Ni_(3)N-NiO heterostructure(hNiNO).By meticulously controlling the surface heating process during plasma processing,such approach allows for the streamlined fabrication of hNiNO *** resulting nano-framework exhibits outstanding catalytic performance,as evidenced by its overpotential of 320 mV at a current density of 10 mA·cm^(-2),in an alkaline *** stands in stark contrast to the performance of NiO-covered Ni_(3)N fabricated using the conventional plasma method(sNiNO).Operando plasma diagnostics,coupled with numerical simulations,further substantiates the influence of surface heating due to auxiliary insulator confinement of the substrate on typical plasma parameters and the formation of the Ni_(3)N-NiO nanostructure,highlighting the pivotal role of controlled surface temperature in creating a high-performance heterostructured electrocatalyst.

关键词： structural modulation auxiliary insulator-confined plasma surface heating control heterostructure electrocatalytic O2 evolution