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Correlation between Brightness Variability and Spectral Index Variability for Fermi Blazars

Research in Astronomy and Astrophysics 2022年第8期22卷 23-33页

作者： Wen-Xin Yang Hu-Bing Xiao Hong-Guang Wang Jiang-He Yang Zhi-Yuan Pei De-Xiang Wu Yu-Hai Yuan Jun-Hui Fan Center for Astrophysics Guangzhou UniversityGuangzhou 510006China Astronomy Science and Technology Research Laboratory of Department of Education of Guangdong Province Guangzhou 510006China Key Laboratory for Astronomical Observation and Technology of Guangzhou Guangzhou 510006China Shanghai Key Lab for Astrophysics Shanghai Normal UniversityShanghai 200234China Department of Physics and Electronics Science Hunan University of Arts and ScienceChangde 415000China

In this work,theγ-ray photon flux,photon spectral index(α_(ph)),variability index(log V.I.),and the synchrotron peak frequency(log v_(p))are compiled for 851 common blazars from the 3 FGL and 4 FGL catalogs and Fan et *** investigate variability properties for Fermi *** calculations and analyses reach following results:(1)the averaged luminosity,spectral index,and variability index of FSRQs are higher than those of BL Lacs for the whole sample.(2)It is found that the spectral index variation is closely anti-correlated with the luminosity variation implying that the spectrum becomes harder when the source becomes brighter in theγ-ray band.(3)Positive correlations are found between the photon spectral index and bothγ-ray luminosity and variability index(log V.I.)for the whole sample,but anti-correlations are found in the two correlations for *** BL Lac subclass,there is a marginal anti-correlation between the photon spectral index and bothγ-ray luminosity,and a positive correlation between the photon spectral index and the variability index(log V.I.).We think those two positive correlations found for the whole sample are apparent.(4)We adopted the SVM machine learning method to separate BL Lacs and FSRQs in theα_(ph)versus log L_(γ)andα_(ph)versus log *** and proposed that a BCU is an FSRQ candidate if it satisfies log V.I.>-10.119 a+24.855,orα_(ph)>-0.048 log L_(γ)+4.498,otherwise,it is a BL Lac *** classification results are quite consistent with those by Kang et al(2019).

关键词： (galaxies:)BL Lacertae objects:general (galaxies:)quasars:general galaxies:active

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Effects of Al2O3 on crystallization, microstructure, and properties of zinc spinel glass–ceramics

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Ceramics International 2025年第17期51卷 23244-23254页

作者： Wei, Shuguang Jiang, Hong Dong, Chuang Xiong, Chunrong Hao, Hongxun Ma, Yanping Li, Minghan & Special Glass Key Lab of Hainan Province Haikou570228 China School of Materials Science and Engineering Hainan University Haikou570228 China Ministry of Education China Hainan Holdings Special Glass Technology Co. Ltd. Chengmai 571924 China State Key Laboratory of Chemical Engineering School of Chemical Engineering and Technology Tianjin University Tianjin300072 China School of Physics and Optoelectronic Engineering Hainan University Haikou570228 China

Spinel glass–ceramics are composite materials with remarkable mechanical properties;however, their enhancement through crystal precipitation remains underexplored. In this study, transparent spinel nano/microcrystalline glasses containing alkali metal oxides were prepared using ZnO, Al2O3, and SiO2 as primary raw materials. When the alkali metal lithium (Li) was combined with high alumina silicate content, it readily bonded with Al and Si atoms, facilitating crystal precipitation. The resulting LixAlxSi1-xO2 composite inhibited ZnAl2O4 crystal precipitation, reducing the mechanical properties of the glass phase and altering the Li content, which subsequently influenced ion exchange processes. Al atoms in the LixAlxSi1-xO2 and ZnAl2O4 composites were found in four- and six-coordinated structures, respectively. By adjusting the Al2O3 dosage, the base glass produced numerous five-coordinated Al species prior to crystal precipitation, promoting the formation of six-coordinated Al species in the ZnAl2O4 crystal structure. This led to the preferential precipitation of ZnAl2O4 crystals and a reduction in LixAlxSi1-xO2 crystal formation. The prepared glass–ceramics demonstrated exceptional mechanical and optical properties. When the Al2O3 content was 33.9 wt%, the bending strength reached 415 MPa. At 35.9 wt% Al2O3, the Vickers hardness was 926 Hv, and the glass–ceramic composite achieved a transmittance of 87.2 %. Compared to conventional glass–ceramic covers for touch screens, the fabricated glass–ceramics exhibited significantly improved mechanical properties. These findings suggest that alkali-bearing spinel glass–ceramics hold great promise for applications in deep-sea pressure-resistant materials and electronic glass covers. © 2025 Elsevier Ltd and Techna Group S.r.l.

关键词： Aluminum oxide

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基于熵和剪切带开发新型非晶合金

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science China Materials 2023年第11期66卷 4143-4164页

作者：冯士东宋贞强张宴会李子敬王利民刘日平 State Key Laboratory of Metastable Materials Science and Technology and College of Materials Science and EngineeringYanshan UniversityQinhuangdao 066004China Key Lab for Microstructural Material Physics of Hebei Province School of ScienceYanshan UniversityQinhuangdao 066004China Hebei Key Lab for Optimizing Metal Product Technology and Performance Yanshan UniversityQinhuangdao 066004China

非晶合金是非晶材料家族中的新成员,由于缺乏原子排列长程有序特征,具有独特的性能和广泛应用前景.然而,非晶合金的形成、成分设计和形变问题在该领域长期未得到解决,制约着新型非晶合金的高效开发.传统上,多组元非晶合金的成分设计主... 详细信息

非晶合金是非晶材料家族中的新成员,由于缺乏原子排列长程有序特征,具有独特的性能和广泛应用前景.然而,非晶合金的形成、成分设计和形变问题在该领域长期未得到解决,制约着新型非晶合金的高效开发.传统上,多组元非晶合金的成分设计主要遵循相图研究范式,以温度调控为出发点,确定低液相线的成分为落脚点,尤其强调深共晶成分.然而,对于缺乏相图的多组元体系则力所不及,亟需新的理论突破.本文综述了非晶转变中的热力学与动力学基本规律,重点探讨了热力学与动力学性质之间的关联性,尤其是梳理了材料熔化熵与熔点粘度、熔点等多个非晶形成经典参量之间的内在关联,提出并论证了熔化熵和振动熵为非晶形成的关键热力学参量,可有效指导高性能非晶合金的设计和表征.结合实际应用中对非晶材料的工程要求,讨论了化学成分调控对非晶合金剪切带的萌生密度和扩展稳定性的影响,并总结了在单调加载和疲劳加载条件下剪切带行为对非晶合金断裂过程的作用.最后展望了振动熵和构型熵之间争议问题,提出未来工作中需要发展具有物理意义玻璃形成能力指标和可靠数据库的需求,混合加载模式下的韧性以及疲劳和韧性之间的权衡等问题.本文为进一步建立高性能非晶材料成分设计路径提供了参考与指导.

关键词： amorphous alloys composition design entropy shear band

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Symmetry-broken atomic ensemble induced by mandated charge for efficient water dissociation in hydrogen generation

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Journal of Energy Chemistry 2025年第4期103卷 274-281页

作者： Ruofan Shen Yanyan Liu Shuling Liu Jianchun Jiang Tao Liu Sehrish Mehdi Ting-Hui Xiao Erjun Liang Baojun Li Laboratory of Zhongyuan Light Key Laboratory of Materials PhysicsMinistry of EducationSchool of PhysicsZhengzhou UniversityZhengzhou 450001HenanChina College of Science Henan Agricultural University63 Nongye RoadZhengzhou 450002HenanChina College of Chemistry Zhengzhou University100 Science RoadZhengzhou 450001HenanChina National Engineering Lab.for Biomass Chemical Utilization Institute of Chemical Industry of Forest ProductsChinese Academy of ForestryNanjing 210042JiangsuChina CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety National Centre for Nanoscience and TechnologyBeijing 100190China

Efficient water dissociation catalysts are important for reducing the activation energy barrier of water molecules in the field of energy conversio ***,symmetry-bro ken Rh ensemble induced by mandated charge was established to boost the catalytic activity toward water *** an experimental verification,the turnover frequency of 1.0-RTO_(V4)in hydrogen generation from ammonia borane hydrolysis reaches up to 2838 min-1(24828 min^(-1)depend on Rh dispersion),exceeding the benchmark set up by state-of-the-art *** transfer of mandated charge from O_(V)to Rh near O_(V)breaks the local symmetry of Rh nanoparticle and forms Rh^(γ-)(electron-aggregation Rh)-Rh interfacial atomic *** symmetry-broken Rh ensemble is the reason for the high activity of the *** work provides an effective electronic regulation strategy based on symmetry-broken atomic ensemble induced by mandated charge,designed to stimulate the limiting activity of metal catalyst in the field of next generation energy chemistry.

关键词： Ammonia borane Hydrogen generation Interfacial atomic ensemble Mandated charge Symmetry-broken

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Integrating Electric Ambipolar Effect for High-Performance Zinc Bromide Batteries

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Nano-Micro Letters 2025年第6期17卷 382-396页

作者： Wenda Li Hengyue Xu Shanzhe Ke Hongyi Zhang Hao Chen Gaijuan Guo Xuanyi Xiong Shiyao Zhang Jianwei Fu Chengbin Jing Jiangong Cheng Shaohua Liu State Key Laboratory of Precision Spectroscopy Engineering Research Center of Nanophotonics and Advanced Instrument(Ministry of Education)School of Physics and Electronic ScienceEast China Normal UniversityShanghai 200241People’s Republic of China Department of Chemistry Tsinghua UniversityHaidian DistrictBeijing 100084People’s Republic of China School of Materials Science and Engineering Xinjiang University666 Shengli RoadUrumqi City 830046People’s Republic of China School of Materials Science and Engineering Zhengzhou University75 Daxue RoadZhengzhou 450052People’s Republic of China State Key Lab of Transducer Technology Shanghai Institute of Microsystem and Information TechnologyChinese Academy of SciencesShanghai 200050People’s Republic of China

The coupling of fast redox kinetics,high-energy density,and prolonged lifespan is a permanent aspiration for aqueous rechargeable zinc batteries,but which has been severely hampered by a narrow voltage range and suboptimal compatibility between the electrolytes and ***,we unprecedentedly introduced an electric ambipolar effect for synergistic manipulation on Zn^(2+)ternary-hydrated eutectic electrolyte(ZTE)enabling high-performance Zn-Br_(2)*** electric ambipolar effect motivates strong dipole interactions among hydrated perchlorates and bipolar ligands of L-carnitine(L-CN)and sulfamide,which reorganized primary cations solvation sheath in a manner of forming Zn[(L-CN)(SA)(H_(2)O)_(4)]^(2+)configuration and dynamically restricting desolvated H2O molecules,thus ensuring a broadened electrochemical window of 2.9 V coupled with high ionic ***,L-CN affords an electrostatic shielding effect and an in situ construction of organic-inorganic interphase,endowing oriented Zn anode plating/stripping reversibly for over 2400 ***,with the synergy of electro/nucleophilicity and exceptional compatibility,the ZTE electrolyte dynamically boosts the conversion redox of Zn-Br_(2)batteries in terms of high specific capacity and stable cycling *** findings open a window for designing electrolytes with synergetic chemical stability and compatibility toward advanced zinc-ion batteries.

关键词： Electric ambipolar effect Hydrated eutectic electrolyte Electrostatic shielding Zinc bromide batteries

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AGN Lifetimes in UV-selected Galaxies: A Clue to Supermassive Black Hole-galaxy Coevolution

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Research in Astronomy and Astrophysics 2022年第1期22卷 104-113页

作者： Xiaozhi Lin Yongquan Xue Guanwen Fang Lulu Fan Huynh Anh N Le Ashraf Ayubinia CAS Key Laboratory for Research in Galaxies and Cosmology Department of AstronomyUniversity of Science and Technology of ChinaHefei 230026China School of Astronomy and Space Science University of Science and Technology of ChinaHefei 230026China School of Mathematics and Physics Anqing Normal UniversityAnqing 246133China Shandong Provincial Key Lab of Optical Astronomy and Solar-Terrestrial Environment Institute of Space ScienceShandong UniversityWeihai264209China

The coevolution between supermassive black holes(SMBHs) and their host galaxies has been proposed for more than a decade,albeit with little direct evidence about black hole accretion activities regulating galaxy star formation at z> *** this paper,we study the lifetimes of X-ray active galactic nuclei(AGNs) in UV-selected red sequence(RS),blue cloud(BC) and green valley(GV) galaxies,finding that AGN accretion activities are most prominent in GV galaxies at z ~1.5-2,compared with RS and BC *** also compare AGN accretion timescales with typical color transition timescales of UV-selected *** find that the lifetime of GV galaxies at z~1.5-2 is very close to the typical timescale when the AGNs residing in them stay in the high-accretion-rate mode at these redshifts;for BC galaxies,the consistency between the color transition timescale and the black hole strong accretion lifetime is more likely to happen at lower redshifts(z <1).Our results support the scenario where AGN accretion activities govern UV color transitions of host galaxies,making galaxies and their central SMBHs coevolve with each other.

关键词： galaxies:active galaxies:formation galaxies:evolution galaxies:high-redshift galaxies:nuclei (galaxies:)quasars:supermassive black holes galaxies:star formation galaxies:statistics

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Four qubit time-bin entangled GHZ-state generation

Four qubit time-bin entangled GHZ-state generation

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2024 IEEE Photonics Conference, IPC 2024

作者： Esmaeilifar, Leili Singh, Ashutosh Lefebvre, Pascal Oblak, Daniel University of Calgary Quantum Cloud Lab Department of Physics and Astronomy Institute for Quantum Science and Technology AB Canada Sorbonne Université Cnrs LIP6 4 Place Jussieu ParisF-75005 France

A pair of time-bin entangled states are generated using the spontaneous parametric down-conversion process in two PPLN crystals. One photon from either source interferes on an optical switch. A four-qubit GHZ-state is... 详细信息

ISBN: (纸本)9798350361957

关键词： Quantum entanglement

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超耐用疏冰涂层的制备及性能研究

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science China Materials 2023年第5期66卷 2071-2078页

作者：卓毅智 Verner Håkonsen 刘思琪李彤王锋罗四海肖森波何健英张志良 Nanomechanical Lab Department of Structural EngineeringNorwegian University of Science and Technology(NTNU)Trondheim 7491Norway NanoLab Norwegian University of Science and Technology(NTNU)Trondheim 7491Norway Ningbo Institute of Materials Technology and Engineering Chinese Academy of SciencesNingbo 315201China Department of Chemistry Norwegian University of Science and Technology(NTNU)Trondheim 7491Norway Institute of Solid State Physics Hefei Institutes of Physical ScienceChinese Academy of SciencesHefei 230031China

被动疏冰涂层作为一种新形防除冰方法,拥有环境友好、耗能低、经济等优势,因此在过去十几年来被广泛研究.但是,目前的主动疏冰涂层仍存在疏冰性与耐久性难以兼容的问题.本文设计了一种兼具高韧性、强基底粘附力和自愈合能力的透明疏冰涂... 详细信息

被动疏冰涂层作为一种新形防除冰方法,拥有环境友好、耗能低、经济等优势,因此在过去十几年来被广泛研究.但是,目前的主动疏冰涂层仍存在疏冰性与耐久性难以兼容的问题.本文设计了一种兼具高韧性、强基底粘附力和自愈合能力的透明疏冰涂层.涂层具有疏水性、光滑表面及低模量,保障了涂层的低冰粘附强度.通过引入类海绵结构,冰粘附强度可降低至26.7±1.1 kPa.涂层高分子网络的多重氢键赋予其高韧性、强基底粘附力和自愈合能力.因此,涂层在35次结冰/除冰循环和600次机械磨损之后能避免涂层剥离并保持疏冰性,且能愈合机械磨损恢复其疏冰性.另外,涂层在海水及近北极气候暴露8个月后仍能保持良好的疏冰性.该工作为耐久性疏冰涂层的设计提供了一种新思路.

关键词： robust icephobic adhesion toughness self-healing

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Experiment of a High Fill Ratio Electro-Optical System for a Ka-Band Traveling Wave Tube

Experiment of a High Fill Ratio Electro-Optical System for a...

引用

International Conference on vacuum Electronics

作者： Duo Xu Hexin Wang Shaomeng Wang Zhanliang Wang Zhigang Lu Huarong Gong Zhaoyun Duan Yubin Gong National Key Lab of Science and Technology on Vacuum Electronics University of Electronic Science and Technology of China Chengdu China

This paper reported the experiments of a high fill ratio pencil beam electro-optical system (EOS). This EOS is for a Ka-band modified angular log-periodic folded waveguide (MALP-FW) traveling wave tube (TWT). The designed operating voltage is 12.06 kV and the desired current is 102 mA. The particle tracking simulation shows the output current of the electron gun is 97.7 mA while it drops down to be 93.9 mA in experiment. The fill ratio in radius and the beam transparency are about 90% and 100%, respectively, in simulation. The obtained beam transparency in experiment is 88.29%.

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Fe-Ni-F electrocatalyst for enhancing reaction kinetics of water oxidation

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Chinese Journal of Structural Chemistry 2024年第2期43卷 60-65页

作者： Yi Zhang Biao Wang Chao Hu Muhammad Humayun Yaping Huang Yulin Cao Mosaad Negem Yigang Ding Chundong Wang School of Chemical Engineering and Pharmacy Key Laboratory of Green Chemical Process of Ministry of EducationKey Laboratory of Novel Reactor and Green Chemical Technology of Hubei ProvinceWuhan Institute of TechnologyWuhan430073PR China Energy Waterand Environment LabCollege of Humanities and SciencesPrince Sultan UniversityRiyadh11586Saudi Arabia School of Integrated Circuits Wuhan National Laboratory for OptoelectronicsHuazhong University of Science and TechnologyWuhan430074PR China Physics Laboratory Industrial Training CenterShenzhen Polytechnic UniversityShenzhen518055PR China Chemistry Department Faculty of ScienceFayoum UniversityFayoum63514Egypt

Highly active and low-cost oxygen evolution reaction(OER)catalytic electrodes are extremely essential for exploration of green hydrogen via water ***,an advanced Fe-Ni-F electrocatalyst is fabricated by a facile annealing strategy using ammonium fluoride,of which the structure feature is unveiled by XRD,FESEM,TEM,EDS,BET,and XPS *** as-prepared Fe-Ni-F addresses a low overpotential of 277 mV and a small Tafel slope of 49 mV dec^(-1)at a current density of 10 mA cm^(-2),significantly outperforming other control samples as well as the state-of-the-art RuO_(2).The advanced nature of our Fe-Ni-F catalyst could also be further evidenced from the robust stability in KOH alkaline solution,showing as 5.41%degradation after 24 h continuous *** analysis,it suggests that the decent catalytic activity should be attributed to the formed bimetallic(oxy)hydroxides because of the introduction of fluoride and the synergistic effect of iron and nickel towards oxygen *** work represents the potential of Fe-and/or Ni-based fluoride as efficient catalyst for low-energy consumption oxygen generation.

关键词： Fluoride Oxygen evolution reaction Fe-Ni-F Reaction kinetics

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