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Identifying dehydration-induced shear velocity anomaly in the Earth’s core-mantle boundary

The Innovation 2025年第1期6卷 47-53,46页

作者： Songsong Han Xiaoming Cui Baolong Zhang Xiaohong Li Sidao Ni Heping Sun Mingqiang Hou Qingyang Hu State Key Laboratory of Geodesy and Earth’s Dynamics Innovation Academy for Precision Measurement Science and TechnologyChinese Academy of SciencesWuhan 430077China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China Center for High Pressure Science and Technology Advanced Research Beijing 100193China

The steep temperature gradient near the bottom of the mantle is known to generate a negative correlation between the shear wave velocity(VS)and the depth in most regions of the D00 layer,as detected by seismological ***,increasing VSwith depth is observed at the D00 layer beneath Central America,where the Farallon slab sinks,and the origin of this anomaly has not beenwell ***,we calculate the thermoelastic constants and obtain the elastic wave velocities of hydrous phase H with various Al contents and cation configurations,which may act as a water carrier to the D00 *** find its VS to be substantially lower than the post-perovskite-type *** dehydration of Al-enriched phase H and the redistribution of Al from the hydrous component to dry silicates would gradually raise the VS below the top of the D00 *** presence of 3.5 wt%water is sufficient to compensate for the thermal effects to match the seismic anomaly at the bottomof themantle beneath Central *** positive slope of VS versus depth in the D00 layer may fingerprint deep water recycling.

关键词： shear velocity calculate thermoelastic constants seismological observationshoweverincreasing Earths core mantle boundary shear wave elastic wave velocities dehydration seismic anomaly

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Nitrogen Reduction to Ammonia by a Phosphorus-Nitrogen PN^(3) P-Mo(V)Nitride Complex:Significant Enhancement via Ligand Postmodification

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CCS Chemistry 2023年第3期5卷 616-623页

作者： Delong Han Priyanka Chakraborty Mei-Hui Huang Li Yang Hao Huang Théo P.Gonçalves Abdul Hamid Emwas Zhiping Lai Jr-Hau He Aleksander Shkurenko Mohamed Eddaoudi Kuo-Wei Huang Division of Physical Science and Engineering King Abdullah University of Science and TechnologyThuwal 23955 KAUST Catalysis Center King Abdullah University of Science and TechnologyThuwal 23955 Core Lab King Abdullah University of Science and TechnologyThuwal 23955 Advanced Membranes and Porous Materials Research Center King Abdullah University of Science and TechnologyThuwal 23955 Department of Materials Science and Engineering City University of Hong KongKowloon 999077 Agency for Science Technologyand ResearchInstitute of Materials Research and Engineering and Institute of Sustainability for ChemicalsEnergy and EnvironmentSingapore 138634

Efforts to develop organometallic complexes for catalytic nitrogen reduction have seen significant progress in recent ***,the strategies for improving the activity of the homogenous catalysts have mainly focused on alternating ligands and ***,we report that the activity and stability of a PN_(P-Mo pincer complex(2)toward dinitrogen(N_(2))reduction were greatly enhanced through postmodification of the PN^(3)P pincer framework of its parent complex(1).A high ratio of NH_(3)/Mo(3525)was achieved in the presence of SmI_(2)as a *** sharp contrast,1 only afforded an NH_(3)/Mo ratio of ***,when supported by an anionic pincer ligand,2 furnished a high oxidation state Mo(V)-nitride complex via N_(2)cleavage as a plausible key intermediate in the catalytic process,suggesting a catalytic cycle that may involve different oxidation states(Ⅱ/Ⅴ)from those with 10-πelectron configuration in the literature.

关键词： molybdenum PN^(3)P samarium(Ⅱ)iodide nitrogen reduction ligand postmodification

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Synthesis and mechanical and elevated temperature tribological properties of a novel high-entropy(TiVNbMoW)C_(4.375) with carbon stoichiometry deviation

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Journal of advanced Ceramics 2023年第2期12卷 242-257页

作者： Jicheng LI Yanchun ZHOU Yunfeng SU Shuna CHEN Qiuan SUN Hengzhong FAN Junjie SONG Litian HU Yongsheng ZHANG State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China Science and Technology on Advanced Functional Composite Laboratory Aerospace Research Institute of Materials&Processing TechnologyBeijing 100076China

High-entropy carbides are a nascent group of ceramics that are promising for high-temperature applications due to the combination of good stability,high hardness(H),high strength,and superior creep resistance that they *** to high melting points and low lattice diffusion coefficients,however,the high-entropy carbides are usually difficult to consolidate to a nearly full *** cope with this challenge,herein,binary carbides including TiC,V_(8)C_(7),NbC,Mo_(2)C,and WC with different carbon stoichiometry were used to prepare dense high-entropy(TiVNbMoW)C_(4.375),and the influence of carbon vacancy on formation ability and mechanical properties of carbon-deficient high-entropy(TiVNbMoW)C_(4.375) were ***,although the starting binary carbides have different crystal structures and carbon stoichiometry,the as-prepared high-entropy material showed a rock-salt structure with a relatively high density(98.1%)and good mechanical properties with hardness of 19.4±0.4 GPa and fracture toughness(KIC)of 4.02 MPa·m^(1/2).More importantly,the high-entropy(TiVNbMoW)C_(4.375) exhibited low coefficient of friction(COF)at room temperature(RT)and 800℃.Wear rate(W)gradually increased with the temperature rising,which were attributed to the formation of low-hardness oxidation films at high temperatures to aggravate *** 800℃,lubricating films formed from sufficient oxidation products of V_(2)O_(5) and MoO_(3) effectively improved tribological behavior of the high-entropy(TiVNbMoW)C_(4.375).Wear mechanisms were mainly abrasive wear resulting from grain pullout and brittle fracture as well as oxidation wear generated from high-temperature *** results are useful as valuable guidance and reference to the synthesis of high-entropy ceramics(HECs)for sliding parts under high-temperature serving conditions.

关键词： high-entropy ceramics(HECs) transition metal(TM)carbides carbon stoichiometry deviation tribological performances wear

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Enhancing the thermoelectric performance of donor-acceptor conjugated polymers through dopant miscibility: a comparative study of fluorinated substituents and side-chain lengths

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Journal of Materials Chemistry A 2024年第16期12卷 9806-9816页

作者： Ding, Jian-Fa Chen, Guan-Lin Liu, Pang-Hsiao Tseng, Kai-Wei Wu, Wei-Ni Lin, Jhih-Min Tung, Shih-Huang Wang, Leeyih Liu, Cheng-Liang Department of Materials Science and Engineering National Taiwan University Taipei10617 Taiwan Institute of Polymer Science and Engineering National Taiwan University Taipei10617 Taiwan Center of Atomic Initiative for New Materials National Taiwan University Taipei10617 Taiwan Center for Condensed Matter Sciences National Taiwan University Taipei10617 Taiwan National Synchrotron Radiation Research Center Hsinchu30076 Taiwan Advanced Research Center for Green Materials Science and Technology National Taiwan University Taipei10617 Taiwan

Conjugated polymers present a compelling option for thermoelectric applications due to their low working temperatures, good compatibility with solution-processing techniques, and high potential for scalability. However, the inherently low electrical conductivities of the pristine conjugated polymers necessitate improvements via doping methods. Doping effectively enhances the electrical conductivity by increasing the charge concentration and mobility within the conjugated polymer matrix. Hence, the present study investigates the compatibility between a ferric chloride (FeCl3) dopant and four distinct conjugated polymers and evaluates the effects of the dopant/polymer combination on the thermoelectric properties of the material. First, the influence of backbone engineering is investigated via a comparison between 4-(3′,4′-difluoro-3,3′′-bis(2-hexyldecyl)-5′′-methyl-[2,2′:5′,2′′-terthiophen]-5-yl)-7-methylbenzo[c][1,2,5]thiadiazole (PC16BTF) and 4-(3,3′′-bis(2-hexyldecyl)-5′′-methyl-[2,2′:5′,2′′-terthiophen]-5-yl)-7-methylbenzo[c][1,2,5]thiadiazole (PC16BTH). These polymers differ in that PC16BTF incorporates two fluorine-atom substituents on the thiophene ring, while PC16BTH contains hydrogen atoms in these positions. Then, the effects of various side-chain lengths are investigated by comparing the abovementioned PC16BTH with both 4-(3,3′′-bis(2-butyloctyl)-5′′-methyl-[2,2′:5′,2′′-terthiophen]-5-yl)-7-methylbenzo[c][1,2,5]thiadiazole (PC12BTH) and 4-methyl-7-(5′′-methyl-3,3′′-bis(2-octyldodecyl)-[2,2′:5′,2′′-terthiophen]-5-yl)benzo[c][1,2,5]thiadiazole (PC20BTH). The FeCl3 dopant was selected for its suitable size and charge transfer capability, which significantly influence the thermoelectric performance of each conjugated polymer. As a result, PC16BTH exhibits the highest power factor (PF) of 22.4 μW m−1 K−2 due to its moderate side-chain length and relatively high doping efficiency. Thus, the present study provides valuable insights into suitable strategies for imp

关键词： Chlorine compounds

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Design of Wideband Quad-Mode Crossed-Dipole Antenna by Using Resonant Modal Theory

Design of Wideband Quad-Mode Crossed-Dipole Antenna by Using...

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2023 International applied Computational Electromagnetics Society Symposium, ACES-China 2023

作者： Xiao, Ruqi Geyi, Wen Wu, Wen School of Electronic and Optical Engineering Nanjing University of Science and Technology Nanjing China Nanjing University of Information Science and Technology Research Center of Applied Electromagnetics Nanjing China

ISBN: (纸本)9781733509657

A quad-mode wideband crossed-dipole antenna is proposed and designed with the resonant modal theory (RMT). The resonant current modes for the antenna consisting of a cross and two parasitic stripes are first determined by RMT. Input terminal is then introduced and positioned at the maximum of the current modes to excite the corresponding field patterns, and, a wideband quad-mode crossed-dipole is obtained, which achieves 49.1% fractional bandwidth at -10 dB of the reflection coefficient and an overall size of 0.62λ0× 0.51λ0× 0.03λ0(λ0 is the free-space wavelength at the center frequency). © 2023 applied Computational Electromagnetics Society (ACES).

关键词： Electromagnetic fields

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Plant Leaf Diseases Detection and Classification Using Spectroscopy

Plant Leaf Diseases Detection and Classification Using Spect...

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World Conference on Information Systems for Business Management, ISBM 2022

作者： Jayswal, Hardikkumar S. Chaudhari, Jitendra P. Department of Information Technology Devang Patel Institute of Advanced Technology and Research Charotar University of Science and Technology Anand Gujarat Changa India Charusat Space Research and Technology Center Charotar University of Science and Technology Anand Gujarat Changa India

ISBN: (纸本)9789811974465

Detection of plant diseases is one of the important aspects in the field of agriculture. The accurate, early detection of plant diseases is very important to save the plant. Plant diseases identified by DNA (Polymerase chain reaction) and RNA-based method which is much complex and time consuming. In this paper we used spectral-based sensing with the combination of machine learning methods to detect and classify the mango disease like anthracnose, powdery mildew and sooty mold. We conducted various field experiments to acquire different vegetation reflectance spectrum profile using spectrometer at Anand Agriculture university, Gujarat, India. A total 20,000 spectral sample collected to detect and classify the diseases with training set and test set ratio is 70% and 30%, respectively. After the encoding the dependent variable training and testing data set were made for train the model. The range of wavelength used to detect a mango disease is 400 nm to 1000 nm. With the help of supervised machine learning algorithm, we achieved classifier accuracy up to 99.9980%. © 2023, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.

关键词： Classification (of information)

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Enhancing reliability in photonuclear cross-section fitting with Bayesian neural networks

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Nuclear science and Techniques 2025年第3期36卷 146-156页

作者： Qian-Kun Sun Yue Zhang Zi-Rui Hao Hong-Wei Wang Gong-Tao Fan Hang-Hua Xu Long-Xiang Liu Sheng Jin Yu-Xuan Yang Kai-Jie Chen Zhen-Wei Wang Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai 201210China School of Physics and Microelectronics Zhengzhou UniversityZhengzhou 450001China School of Physical Science and Technology ShanghaiTech UniversityShanghai 201210China

This study investigates photonuclear reaction(γ,n)cross-sections using Bayesian neural network(BNN)*** determining the optimal network architecture,which features two hidden layers,each with 50 hidden nodes,training was conducted for 30,000 iterations to ensure comprehensive data *** analyzing the distribution of absolute errors positively correlated with the cross-section for the isotope 159Tb,as well as the relative errors unrelated to the cross-section,we confirmed that the network effectively captured the data features without *** with the TENDL-2021 Database demonstrated the BNN's reliability in fitting photonuclear cross-sections with lower average *** predictions for nuclei with single and double giant dipole resonance peak cross-sections,the accurate determination of the photoneutron reaction threshold in the low-energy region,and the precise description of trends in the high-energy cross-sections further demonstrate the network's generalization ability on the validation *** can be attributed to the consistency of the training *** using consistent training sets from different laboratories,Bayesian neural networks can predict nearby unknown cross-sections based on existing laboratory data,thereby estimating the potential differences between other laboratories'existing data and their own measurement *** measurements of photonuclear reactions on the newly constructed SLEGS beamline will contribute to clarifying the differences in cross-sections within the existing data.

关键词： Photoneutron reaction Bayesian neural network Machine learning Gamma source SLEGS

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Pulse-doubling perovskite nanowire lasers enabled by phonon-assisted multistep energy funneling

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Light(science & Applications) 2024年第8期13卷 1645-1654页

作者： Chunhu Zhao Jia Guo Jiahua Tao Junhao Chu Shaoqiang Chen Guichuan Xing Hunan Provincial Key Laboratory of Carbon Neutrality and Intelligent Energy School of Resource&EnvironmentHunan University of Technology and Business410205 ChangshaChina Engineering Research Center for Nanophotonics and Advanced Instrument Ministry of EducationSchool of Physics and Electronic ScienceEast China Normal University200241 ShanghaiChina Joint Key Laboratory of the Ministry of Education Institute of Applied Physics and Materials EngineeringUniversity of Macao999078 MacaoChina

Laser pulse multiplication from an optical gain medium has shown great potential in miniaturizing integrated optoelectronic *** multiple quantum wells(MQWs)structures have recently been recognized as an effective gain media capable of doubling laser pulses that do not rely on external optical *** the light amplifications enabled with pulse doubling are reported based on the perovskite MQWs thin films,the micronanolasers possessed a specific cavity for laser pulse multiplication and their corresponding intrinsic laser dynamics are still ***,a single-mode double-pulsed nanolaser from self-assembled perovskite MQWs nanowires is realized,exhibiting a pulse duration of 28 ps and pulse interval of 22 ps based on single femtosecond laser pulse *** is established that the continuous energy building up within a certain timescale is essential for the multiple population inversion in the gain medium,which arises from the slowing carrier localization process owning to the stronger exciton–phonon coupling in the smaller-n ***,the double-pulsed lasing is achieved from one fast energy funnel process from the adjacent small-n QWs to gain active region and another slow process from the spatially separated *** report may shed new light on the intrinsic energy relaxation mechanism and boost the further development of perovskite multiple-pulse lasers.

关键词： doubling energy phonon

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Photocatalytic degradation of antibiotic sulfamethizole by visible light activated perovskite LaZnO_(3)

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Journal of Environmental sciences 2024年第10期144卷 212-224页

作者： Bui The Huy XCuong Nguyen Vu Khac Hoang Bui Nguyen Ngoc Tri Iqra Rabani Nhu Hoa Thi Tran Quang Viet Ly Hai Bang Truong Major of Biomedical Engineering Division of Smart HealthcareCollege of Information Technology and ConvergencePukyong National UniversityBusan 48513Korea Center for Advanced Chemistry Institute of Research and DevelopmentDuy Tan UniversityDa Nang 550000Viet Nam Faculty of Environmental and Chemical Engineering Duy Tan UniversityDa Nang 550000Viet Nam Department of Environment and Energy Sejong UniversitySeoul 05006Korea Lab of Computational Chemistry and Modelling Department of ChemistryFaculty of Natural SciencesQuy Nhon UniversityQuy NhonViet Nam Department of Nanotechnology and Advanced Materials Engineering Sejong UniversitySeoul 05006Korea Faculty of Materials Science and Technology University of ScienceHo Chi Minh City 700000Viet Nam Vietnam National University Ho Chi Minh City 700000Viet Nam Department of Environmental Engineering Seoul National University of Science and TechnologySeoul 01811Korea Optical Materials Research Group Science and Technology Advanced InstituteVan Lang UniversityHo Chi Minh CityViet Nam Faculty of Applied Technology School of TechnologyVan Lang UniversityHo Chi Minh CityViet Nam

In thiswork,the perovskite LaZnO_(3) was synthesized via sol-gel method and applied for photocatalytic treatment of sulfamethizole(SMZ)antibiotics under visible light *** was almost completely degraded(99.2%±0.3%)within 4 hr by photocatalyst LaZnO_(3) at the optimal dosage of 1.1 g/L,with amineralization proportion of 58.7%±0.4%.The efficient performance of LaZnO_(3) can be attributed to itswide-range light absorption and the appropriate energy band edge levels,which facilitate the formation of active agents such as·O_(2)^(−),h^(+),and·*** integration of RP-HPLC/Q-TOF-MS and DFT-based computational techniques revealed three degradation pathways of SMZ,which were initiated by the deamination reaction at the aniline ring,the breakdown of the sulfonamidemoieties,and a process known as Smile-type rearrangement and SO2 *** toxicity of SMZ and the intermediateswere analyzed by quantitative structure activity relationship(QSAR),indicating the effectiveness of LaZnO_(3)-based photocatalysis in preventing secondary pollution of the intermediates to the ecosystem during the degradation *** visible-light-activated photocatalyst LaZnO_(3) exhibited efficient performance in the occurrence of inorganic anions and maintained high durability across multiple recycling tests,making it a promising candidate for practical antibiotic treatment.

关键词： Perovskite Antibiotics Photocatalysis Density functional theory Toxicity

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Si-Based Anodes:Advances and Challenges in Li-Ion Batteries for Enhanced Stability

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Electrochemical Energy Reviews 2024年第1期7卷 333-368页

作者： Hongshun Zhao Jianbin Li Qian Zhao Xiaobing Huang Shuyong Jia Jianmin Ma Yurong Ren School of Materials Science and Engineering Jiangsu Province Engineering Research Center of Intelligent Manufacturing Technology for the New Energy Vehicle Power BatteryChangzhou Key Laboratory of Intelligent Manufacturing and Advanced Technology for Power BatteryChangzhou UniversityChangzhou 213164JiangsuChina College of Chemistry and Materials Engineering Hunan University of Arts and ScienceChangde 415000HunanChina School of Chemistry Tiangong UniversityTianjin 300387China

Owing to their advantages,such as a high energy density,low operating potential,high abundance,and low cost,rechargeable silicon(Si)anode lithium-ion batteries(LIBs)have attracted considerable *** advancements in Si-based LIBs have been made over the past ***,because the cycle instability is a crucial factor in the half/full-battery design and significantly affects the consumption of active components and the weight of the assembled battery,it has become a concern in recent *** paper presents a thorough analysis of the recent developments in the enhancement methods for the stability of *** in situ and operando characterizations are performed to thoroughly evaluate the electrochemical reactions,structural evolution,and degradation *** for enhancing the cycle stability of Si anodes are systematically divided from a design perspective into several categories,such as the structural regulation,interfacial design,binder architecture,and electrolyte *** advantages and disadvantages of several methods are emphasized and thoroughly evaluated,offering insightful information for the logical design and advancement of cutting-edge solutions to address the deteriorating low-cycle stability of silicon-based ***,the conclusions and potential future research perspectives for promoting the cycling instability of silicon-based LIBs are presented.

关键词： Lithium-ion batteries Si-based anodes Cycling stability Failure mechanisms In situ characterization methods Modification strategies

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