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Spectral and Timing Analysis of the Black Hole Transient MAXI J1631–479 During its 2019 Outburst Observed with Insight-HXMT

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Research in Astronomy and Astrophysics 2022年第11期22卷 21-33页

作者： yu-Cong Fu l.M.Song G.Q.Ding S.N.Zhang J.l.Qu S.Zhang l.Zhang Q.C.Bu y.Huang X.Ma Z.X.yang y.l.tuo X.F.lu D.K.Zhou B.y.Wu T.M.li y.C.Xu Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqiXinjiang 830011China University of Chinese Academy of Sciences Chinese Academy of SciencesBeijing 100049China Key laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China Institut fur Astronomie und Astrophysik Kepler Center for Astro and Particle PhysicsEberhard Karls UniversitatSand 1D-72076 TübingenGermany

We report spectral and timing analysis of the black hole transient MAXI J1631–479 during the hard intermediate state of its 2019 outburst from the Insight-Hard X-ray Modulation Telescope(Insight-HXMT)*** find that the energy dependence of the type-C quasi-periodic oscillation(QPO)frequency evolves with time:during the initial rise of a small flare(~MJD 58526.0-58527.1),the QPO frequency increases with increasing energy from~1 to~100 ke V,and then the frequency remains constant after MJD *** discover a possible new phenomenon of Fe line’s QPO frequency jump that has never been observed for other black hole transients:during the small flare,the QPO frequency around the Fe line energy is higher than any other energy band,with the frequency difference Δf=0.25±0.08 Hz between 5.5–7.5 ke V and other energy *** spectral analysis shows that the evolution of QPOs is related to the equivalent width of the narrow Fe line,and its equivalent width increases during this small *** propose that the QPO frequency difference results from the differential precession of a vertically extended jet,and the higher QPO frequency of Fe line could be caused by the layered jet when the jet scale *** the same time,the evolution of QPOs is related to the accretion rate,while the energy dependence of QPOs supports the existence of deceleration in the vertically distributed jet.

关键词： accretion accretion disks stars:black holes X-rays:binaries

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Synergistic effect of bonding heterogeneity and phonon localization in introducing excellent thermoelectric properties in layered heteroanionic NdZnSbO material

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Journal of Energy Chemistry 2025年第1期100卷 259-272页

作者： Da Wan Shuwei Tang Shulin Bai Xiaodong li Peng Ai Wanrong Guo tuo Zheng College of Materials Science and Engineering Liaoning Technical University Faculty of Chemistry Northeast Normal University

layered rare-earth metal oxides, harnessing the dual properties of oxides and two-dimensional layered materials, exhibit remarkable thermal stability and quantum confinement effects. Therefore, this work adopts the first-principles calculation combined with the Boltzmann transport theory to predict the thermoelectric properties of NdZnSbO compound. The coexistence of weak interlayer van der Waals interactions, robust intralayer ionic bonding, and partial covalent bonding leads to remarkable bonding heterogeneity, which engenders pronounced phonon scattering and imposes constraints on thermal transport along the out-of-plane direction. The weakened chemical bonds induced by the antibonding states, together with the rattling-like behavior of the Zn atom, culminate in the profound anharmonicity in the layered NdZnSbO compound. The weakening bond and heavy element contribute to the softness of phonon modes, which significantly diminishes the phonon group velocity. The redistribution-dominated four-phonon scattering process spans a large optical gap, which effectively reduces the lattice thermal conductivity. The NdZnSbO compound exhibits direct semiconductor characteristic with a bandgap of 0.73 e V by adopting the Heyd-Scuseria-Ernzerhof(HSE06) functional in combination with spin–orbit coupling(SOC) effect. The multi-valley feature of NdZnSbO compound augur favorably for band degeneracy, thus amplifying the power factor. Consequently, an optimal figure-of-merit(ZT) of 3.40 at 900 K is achieved for the n-type NdZnSbO compound. The present study delves deeply insights into the origins for the low thermal conductivity of NdZnSbO compound and proposes an optimization scheme to enhance overall thermoelectric performance.

关键词： Bond strength (chemical)

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Anomalous quality factor evolution of induced transparency in a virtualized coupled-oscillator system

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 148-155页

作者： yunhan yang Han Jia tuo liu yuzhen yang Jun yang Key laboratory of Noise and Vibration Research Institute of Acoustics Chinese Academy of Sciences University of Chinese Academy of Sciences State Key laboratory of Acoustics Institute of Acoustics Chinese Academy of Sciences

The phenomenon of induced transparency, characterized by a high quality(Q) factor, holds significant importance in the fields of high-precision sensing, energy storage and wave manipulation. Conventional transparency systems are often constrained by the limited experimentally accessible parameter space and the lack of independent control over intrinsic parameters, thereby hindering advanced research on high-Q effects. Here we propose a virtualized coupled-oscillator system that enables reconfigurable induced transparency in the reflection spectrum. By virtually incorporating a pair of coupled oscillators into an individual acoustic meta-atom, we achieve the manipulation of induced transparency in a decoupled, wide-ranging, and elaborate manner. Exploiting the diverse evolutions across the intrinsic parameter space, we show experimentally a counter-intuitive increase in the Q-factor of the transparency window, which is attributed to the enhanced dissipation of the bright ***, a constant group delay at the center frequency is observed accompanying this evolution. Our work demonstrates an intriguing platform as well as a novel strategy to engineer high-Q induced transparency phenomenon, and paves the way towards applications in programmable acoustic sensors, filters and slow-wave devices.

关键词： induced transparency acoustic meta-atom high quality-factor scattering programmable intrinsic parameter

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Exploring the mechanical behavior and microstructure of compacted loess subjected to dry-wet cycles and chemical contamination

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第9期16卷 3673-3695页

作者： yongpeng Nie Wankui Ni Xiangfei lü Wenxin tuo College of Geological Engineering and Geomatics Chang'an UniversityXi'an710054China Department of Civil Engineering Nagoya Institute of TechnologyNagoya466-8555Japan School of Water and Environment Chang'an UniversityXi'an710054China

Due to climatic factors and rapid urbanization,the soil in the loess Plateau,China,experiences the coupled effects of dry-wet cycles and chemical *** the mechanical behavior and corresponding microstructural evolution of contaminated loess subjected to dry-wet cycles is essential to elucidate the soil degradation ***,direct shear and consolidation tests were performed to investigate the variations in mechanical properties of compacted loess contaminated with acetic acid,sodium hydroxide,and sodium sulfate during dry-wet *** mechanical response mechanisms were investigated using zeta potential,mineral chemical composition,and scanning electron microscopy(SEM)*** results indicate that the mechanical deterioration of sodium hydroxidecontaminated loess during dry-wet cycles decreases with increasing contaminant concentration,which is mainly attributed to the thickening of the electrical double layer(EDl)by Nat and the precipitation of calcite,as well as the formation of colloidal flocs induced by OH,thus inhibiting the development of large pores during the dry-wet *** contrast,the attenuation of mechanical properties of both acetic acid-and sodium sulfate-contaminated loess becomes more severe with increasing contaminant concentration,with the latter being more particularly *** is primarily due to the reduction of the EDl thickness and the erosion of cement in the acidic environment,which facilitates the connectivity of pores during dry-wet ***,the salt expansion generated by the drying process of saline loess further intensifies the structural ***,the mechanical performance of compacted loess is sensitive to both pollutant type and concentration,exhibiting different response patterns in the dry-wet cycling condition.

关键词： Contaminated loess Dry-wet cycles Compressibility Shear strength Microstructural evolution

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Cortical hem signaling center: functions, development, and potential implications for evolution and brain disorders

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Neural Regeneration Research 2025年第4期20卷 1079-1080页

作者： Victor V.Chizhikov Igor y.Iskusnykh Department of Anatomy and Neurobiology University of Tennessee Health Science CenterMemphisTNUSA

Development of the telencephalon relies upon several signaling centers-localized cellular populations that supply secreted factors to pattern the cortical *** such signaling center is the cortical hem,which arises during embryonic development at the telencephalic dorsal midline,adjacent to the choroid plexus and hippocampal primordium(Figure 1A).While the cortical hem has also been described in reptiles and birds,most of our knowledge about the developmental roles of the cortical hem is derived from the analysis in *** cortical hem produces several types of secreted molecules,including wingless-related integration site(Wnt)and bone morphogenetic(Bmp)*** cortical hem is particularly important for the development of the hippocampus,which is involved in learning and memory,and the neocortex,which is the most complex brain region that mediates multiple types of behavior and higher cognitive functions(Mangale et al.,2008;Dal-Valle-Anton and Borrell,2022).

关键词： epithelium Figure center

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Solidification segregation behavior of Nb-containing 310S steel

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Journal of Iron and Steel Research International 2023年第1期30卷 82-87页

作者： yu-tuo Zhang Hao Zou School of Materials Science and Engineering Shenyang Ligong UniversityShenyang 110159LiaoningChina Institute of Metal Research Chinese Academy of SciencesShenyang 110016LiaoningChina

The solidification characteristics and segregation behavior of solute elements Nb,Ni,Mn,Si,Cr and C in 0.3 wt.%Nb-310S steel were investigated using the isothermal solidification quenching experiment and Thermo-Calc *** phase transformation for 0.3%Nb-310S steel under equilibrium condition can be summarized as follows:liquid(l)→l+γ(1406℃)→γ(1334℃)→γ+NbC(1322℃)→γ+NbC+M_(23)C_(6)(1006℃)→γ+NbC+M_(23)C_(6)→σ(755℃).The results showed that the solidification began with the formation of primary austenite *** volume fraction of the liquid phase decreased rapidly as the temperature decreased in the initial solidification stage,and then,the liquid phase fraction decreased *** austenite formed,Mn and Ni were enriched in the solid phase,while Nb and C were rejected into the *** was present the highest segregation coefficient in 0.3%Nb-310S austenitic stainless *** segregation of Nb was the most serious,followed by Mn,Ni and *** and Si exhibited slight segregation during the *** solidification was terminated by the formation of NbC phase.

关键词： 310S steel Nb Solidification Segregation Thermo-Calc calculation

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Overestimated solar water splitting performance onoxide semiconductor anodes

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Science China Materials 2017年第1期60卷 90-92页

作者： tuo Wang Jinlong Gong Key laboratory for Green Chemical Technology of Ministry of Education School of Chemical Engineering and Technology Tianjin University Tianjin 300072 China Collaborative Innovation Center of Chemical Science and Engineering Tianjin 300072 China

Water oxidation is a 4-electron uphill energy process thatlargely limits the overall water splitting reaction thermody-namically and kinetically [1]. Photocurrent measurementis one of the most important approaches to evaluate the per-formance of a photoanode. It has been well realized thatphotocurrent may render exaggerated performance whenphotocorrosion of electrode occurs, such as the case of ZnOand CdS or when sacrificial reagents are present in the elec-trolyte. However, the choice of electrolyte could be anothervery important but easily overlooked issue for the valid in-terpretation of photocurrent.

关键词：光电电流水化氧化作用半导体阳电极材料科学

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Cranial morphology of the Silurian sarcopterygian Guiyu oneiros (Gnathostomata:Osteichthyes)

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Science China Earth Sciences 2010年第12期53卷 1836-1848页

作者： QIAO tuo ZHU Min Key laboratory of Evolutionary Systematics of Vertebrates Institute of Vertebrate Paleontology and PaleoanthropologyChinese Academy of SciencesBeijing 100044China Graduate School of Chinese Academy of Sciences Beijing 100049China

Cranial morphological features of the stem-group sarcopterygian Guiyu oneiros Zhu et al.,2009 provided here include the dermal bone pattern and anatomical details of the *** on those features,we restored,for the first time,the skull roof bone pattern in the Guiyu clade that comprises Psarolepis and *** with Onychodus,Achoania,coelacanths,and actinopterygians show that the posterior nostril enclosed by the preorbital or the preorbital process is shared by actinopterygians and sarcopterygians,and the lachrymals in sarcopterygians and actinopterygians are not *** endocranium closely resembles that of Psarolepis,Achoania and Onychodus;however,the attachment area of the vomer possesses irregular ridges and grooves as in youngolepis and *** orbito-nasal canal is positioned mesial to the nasal capsule as in youngolepis and *** position of the hypophysial canal at the same level or slightly anterior to the ethmoid articulation represents a synapmorphy of the Guiyu *** large attachment area of the basicranial muscle indicates the presence of a well-developed intracranial joint in Guiyu.

关键词： Sarcopterygii Osteichthyes Cranial morphology homology Silurian China

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Strategic sill pillar design for reduced hanging wall overbreak in longhole mining

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International Journal of Mining Science and Technology 2021年第5期31卷 975-982页

作者： tuo Chen Hani S.Mitri Department of Mining and Materials Engineering Mc Gill UniversityMontrealQuebec H3A 0E8Canada

Steeply dipping,vein and tabular orebodies are traditionally extracted with longitudinal retreat mining methods such as Eureka and Avoca in a bottom-up sequence with delayed *** increase productivity,sill pillars in the orebody are used to separate mining zones thus allowing production to take place simultaneously in two or more *** such mining methods are productive,they may be accompanied with high volumes of hanging wall overbreak causing significant unplanned ore *** this work,it is shown through a mine design case study of a narrow vein deposit that a sill pillar could also play a significant role in limiting hanging wall *** demonstrate the role of sill pillar,a novel numerical modelling scheme is proposed to account for progressive stope wall overbreak.A numerical modelling approach of element death and rebirth is developed to allow for the detected stope overbreak to be immediately removed and replaced with backfill material before upper-level stope *** is further shown that the average overbreak volume could be reduced by as much as 33%when the sill pillar is strategically placed in the lower half of a mine plan.

关键词： Underground mine design longitudinal mining Sill pillar design Unplanned ore dilution Numerical modelling

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Distributed Secure State Estimation of Multi-Agent Systems Under Homologous Sensor Attacks

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IEEE/CAA Journal of Automatica Sinica 2023年第1期10卷 67-77页

作者： yukun Shi youqing Wang Jianyong tuo the College of Information Science and Technology Beijing University of Chemical TechnologyBeijing 100029China IEEE

This paper addresses the problem of distributed secure state estimation for multi-agent systems under homologous sensor *** types of secure luenberger-like distributed observers are proposed to estimate the system state and attack signal ***,the proposed two observers are applicable to deal with the cases in the presence and absence of time delays during network *** is also shown that the proposed observers can ensure the attack estimations from different agents asymptotically converge to the same *** conditions for guaranteeing the asymptotic convergence of the estimation errors are *** examples are finally provided to demonstrate the effectiveness of the proposed results.

关键词： Consensus-based luenberger-like observer distributed secure state estimation homologous signal

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