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Optical monitoring of the Seyfert galaxy NGC 4151 and possible periodicities in its historical light curve

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Research in Astronomy and Astrophysics 2014年第8期14卷 923-932页

作者： Di-Fu Guo shao-ming hu Jun Tao Hong-Xing Yin Xu Chen Hong-Jian Pan Shandong Provincial Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment Institute of Space SciencesSchool of Space Science and PhysicsShandong University Shanghai Astronomical Observatory Chinese Academy of Sciences

We report B, V and R band CCD photometry of the Seyfert galaxy NGC 4151 obtained with the 1.0m telescope at Weihai Observatory of Shandong University and the 1.56 m telescope at Shanghai Astronomical Observatory from 2005 December to 2013 February. Combining all available data from literature, we have constructed a historical light curve from 1910 to 2013 to study the periodicity of the source using three different methods （the Jurkevich method, the Lomb-Scargle periodogram method and the Discrete Correlation Function method）. We find possible periods of P1 = 4 ± 0.1,/92 = 7.5 ±0.3 and P3 = 15.9± 0.3 yr.

关键词： methods data analysis -- galaxies: active -- galaxies individual (NGC 4151)

Discovery of a deep, low mass ratio overcontact binary GSC 03517–00663

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Research in Astronomy and Astrophysics 2015年第6期15卷 889-895页

作者： Di-Fu Guo Kai Li shao-ming hu Yun-Guo Jiang Dong-Yang Gao Xu Chen Shandong Provincial Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment Institute of Space Sciences Shandong University Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of Sciences

When observing blazars, we identified a new eclipsing binary named GSC 03517-00663. The light curves of GSC 03517-00663 are typical of EW-type light curves. Based on the observation using the 1 m telescope at the Weihai Observatory of Shandong University, complete VRI light curves were determined. Then, we analyzed the multiple light curves using the Wilson-Devinney program. It was found that GSC 03517-00663 has a mass ratio of q = 0.164 and a degree of contact of f = 69.2%. GSC 03517-00663 is a deep, low mass ratio overcontact binary. The light curves of GSC 03517-00663 show a strong O＇Connell effect, which was explained by employing a dark spot on the secondary component.

关键词： stars binaries close -- stars binaries eclipsing -- stars individual (GSC 03517-00663)

Photometric investigations on two totally eclipsing contact binaries:V342 UMa and V509 Cam

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Research in Astronomy and Astrophysics 2019年第10期19卷 75-86页

作者： Kai Li Qi-Qi Xia Jin-Zhong Liu Yu Zhang Xing Gao shao-ming hu Di-Fu Guo Xu Chen Yuan Liu Shandong Provincial Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment Institute of Space Sciences Shandong University Weihai 264209 China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of Sciences Kunming 650216 China Xinjiang Astronomical Observatory Chinese Academy of Sciences Urumqi 830011 China Qilu Institute of Technology Jinan 250200 China

By analyzing two sets of complete BV Rc Ic light curves for V342 UMa and three sets of complete BV Rc Ic light curves for V509 Cam, we determined that the two systems are both W-subtype contact binaries and that V342 UMa manifests a shallow contact configuration, while V509 Cam exhibits a medium contact configuration. Given that both of them are totally eclipsing binaries, the physical parameters derived only by the photometric light curves are reliable. Meanwhile, the period changes of the two targets were analyzed based on all available eclipsing times. We discovered that V342 UMa shows long-term period decrease with a rate of-1.02(±0.54)× 10^-7 d yr^-1 and that V509 Cam displays long-term period increase with a rate of 3.96(±0.90)× 10^-8 d yr^-1. Both the conservative mass transfer and angular momentum loss via magnetic stellar winds can be used to interpret the long-term period decrease of V342 UMa. The longterm period increase of V509 Cam can be explained by mass transfer from the less massive star to the more massive one. The absolute parameters of the two binaries were estimated according to their Gaia distances and our derived photometric solution results. This method can be extended to other contact binaries without radial velocities but with reliable photometric solutions. Their evolutionary states were investigated and we found that they reveal properties that are identical to other W-subtype contact systems.

关键词： stars binaries close-stars eclipsing-stars individual (V342UMa, V509Cam)

Experimental Study of Local Scour Around Four Piles Under Different Attack Angles and Gap Ratios

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China Ocean Engineering 2024年第4期38卷 612-624页

作者： LIU ming-ming TANG Guo-qiang JIN Xin GENG shao-yang School of Architecture and Engineering Liaocheng UniversityLiaocheng 252000China Water-Sediment Regulation and Sand Effective Utilization Special Laboratory of Shandong Provincial Education Department Liaocheng UniversityLiaocheng 252000China State Key Laboratory of Coastal and Offshore Engineering Dalian University of TechnologyDalian 116024China College of Electronic Engineering Chengdu University of Information TechnologyChengdu 610225China College of Energy Chengdu University of TechnologyChengdu 610059China

In an effort to investigate and quantify the patterns of local scour,researchers embarked on an in-depth study using a systematic experimental *** research focused on the effects of local scour around a set of four piles,each subjected to different hydromechanical *** particular,this study aimed to determine how different attack angles—the angles at which the water flow impinges on the piles,and gap ratios—the ratios of the spacing between the piles to their diameters,influence the extent and nature of scour.A comprehensive series of 35 carefully designed experiments were orchestrated,each designed to dissect the nuances in how the gap ratio and attack angle might contribute to changes in the local scour observed at the base of pile *** these experimental trials,a wealth of local scour data were collected to support the *** data included precise topographic profiles of the sediment bed around the pile groups,as well as detailed scour time histories showing the evolution of scour at strategic feature points throughout the test *** analysis of the experimental data provided interesting *** study revealed that the interplay between the gap ratio and the attack angle had a pronounced influence on the scouring dynamics of the pile *** of the key observations was that the initial phases of scour,particularly within the first hour of water flow exposure,were characterized by a sharp increase in the scour depth occurring immediately in front of the *** this initial rapid development,the scour depth transitioned to a more gradual change *** contrast,the scour topography around the piles continuously *** suggests that sediment displacement and the associated sculpting of the seabed around pile foundations are sustained and progressive processes,altering the underwater landscape over *** results of this empirical investigation have significant implications for the design and constructio

关键词： local scour piles gap ratio attack angle

Tighter sum uncertainty relations via(α,β,γ)weighted Wigner–Yanase–Dyson skew information

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Communications in Theoretical Physics 2024年第3期76卷 91-99页

作者： Cong Xu Zhaoqi Wu shao-ming Fei School of Mathematical Sciences Capital Normal UniversityBeijing 100048China Department of Mathematics Nanchang UniversityNanchang 330031China Max-Planck-Institute for Mathematics in the Sciences 04103 LeipzigGermany

We establish tighter uncertainty relations for arbitrary finite observables via(α,β,γ)weighted Wigner–Yanase–Dyson((α,β,γ)WWYD)skew *** results are also applicable to the(α,γ)weighted Wigner–Yanase–Dyson((α,γ)WWYD)skew information and the weighted Wigner–Yanase–Dyson(WWYD)skew *** also present tighter lower bounds for quantum channels and unitary channels via(α,β,γ)modified weighted Wigner–Yanase–Dyson((α,β,γ)MWWYD)skew *** examples are provided to illustrate the tightness of our uncertainty relations.

关键词： quantum channels (α,β,γ)WWYD skew information (α,β,γ)MWWYD skew information uncertainty relations

Signifying quantum uncertainty relations by optimal observable sets and the tightest uncertainty constants

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Science China(Physics,Mechanics & Astronomy) 2024年第9期67卷 43-50页

作者： Xiao-Bin Liang Bo Li shao-ming Fei School of Mathematics and Computer Science Shangrao Normal UniversityShangrao 334001China Quantum Information Research Center Shangrao Normal UniversityShangrao 334001China School of Mathematical Sciences Capital Normal UniversityBeijing 100048China

Quantum uncertainty relations constrain the precision of measurements across multiple non-commuting quantum mechanical ***,we introduce the concept of optimal observable sets and define the tightest uncertainty constants to accurately describe these measurement *** any quantum state,we establish optimal sets of three observables for both product and summation forms of uncertainty relations,and analytically derive the corresponding tightest uncertainty *** demonstrate that the optimality of these sets remains consistent regardless of the uncertainty relation ***,the existence of the tightest constants excludes the validity of standard real quantum mechanics,underscoring the essential role of complex numbers in this ***,our findings resolve the conjecture posed in[***.118,180402(2017)],offering novel insights and potential applications in understanding preparation uncertainties.

关键词： uncertainty relation the tightest uncertainty constants optimal observable sets

Deposition of thin TiO_(2)films on fluorophlogopite particle surface by CVD in fluidized bed reactor to prepare silver pearlescent pigments

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Particuology 2024年第6期89卷 88-98页

作者： ming Liu Guoqiang shao Pengpeng Lv Jun Li Qingshan Zhu State Key Laboratory of Multiphase Complex Systems Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China School of Chemical Engineering University of Chinese Academy of SciencesBeijing 100049China

Two critical parameters:Glossiness and chromaticity space of pearlescent pigments were evaluated based on crystallinity and grain *** the roughness and the vertical distance evolution along the surface of deposited TiO_(2)film are affected by the *** optimal crystallinity of TiO_(2)was deposited at the temperature of 350℃.The TiCl4 concentration effectively changed the grain ***,the high flow rate of fluidizing gas and optimal gas–solid ratio(<0.11 m^(3)/(kg h))restricted the change of TiCl_(4)concentrations in fluidized bed *** this case,the grain size of the deposited TiO_(2)film was about 55 *** on the grain size,the color of pearlescent pigments was adjusted by controlling the film thickness based on TiO_(2)***,the silver pearlescent pigment with high glossiness was prepared by chemical vapor deposition method in a fluidized bed reactor.

关键词： Fluidized bed chemical vapor deposition TiO_(2)film deposition Pearlescent pigment Free powder restrain Crystal growth

Propagation Properties of Shock Waves in Polyurethane Foam based on Atomistic Simulations

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Defence Technology（防务技术） 2024年第1期31卷 117-129页

作者： Zhiqiang hu Jianli shao Shiyu Jia Weidong Song Cheng Wang State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China

Porous materials are widely used in the field of protection because of their excellent energy absorption *** this work,a series of polyurethane microscopic models are established and the effect of porosity on the shock waves is studied with classical molecular dynamics ***,shock hugoniot relations for different porosities are obtained,which compare well with the experimental *** pores collapse and form local stress wave,which results in the complex multi-wave structure of the shock *** microstructure analysis shows that the local stress increases and the local velocity decreases gradually during the process of pore collapse to complete ***,it leads to stress relaxation and velocity *** shock stress peaks can be fitted with two exponential functions,and the amplitude of attenuation coefficient decreases with the increase of ***,the pore collapse under shock or non-shock are discussed by the entropy increase rate of the *** energy is dissipated mainly through the multiple interactions of the waves under *** energy is dissipated mainly by the friction between atoms under non-shock.

关键词： Polyurethane foam Shock wave Attenuation Atomistic simulation

Ferrite features in simulated transition zone of EH36 shipbuilding steel submerged arc welded by CaF_(2)-SiO_(2)-MnO fluxes

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Journal of Iron and Steel Research International 2024年第4期31卷 790-796页

作者： ming Zhong Dong hu Da-ming Guo Somnath Basu Cong Wang Key Laboratory for Ecological Metallurgy of Multimetallic Mineral(Ministry of Education) Northeastern UniversityShenyang 110819LiaoningChina School of Metallurgy Northeastern UniversityShenyang 110819LiaoningChina The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina Department of Metallurgical Engineering and Materials Science Indian Institute of Technology BombayMumbai 400076MaharashtraIndia

Ferrite features in the simulated transition zone welded with CaF_(2)-SiO_(2)-MnO fluxes containing various MnO contents have been *** laser scanning microscopy has been applied to simulate the thermal cycling of the transition zone and the phase transformations during cooling have been in-situ *** has been found that the appearance temperature for ferrite side plate decreases with increasing Mn content in the weld metals caused by MnO content ***,growth rates for both ferrite side plate and acicular ferrite are significantly enhanced with a higher Mn content of weld ***,from the statistical fractions of salient microstructures,for all samples,the acicular ferrite,grain boundary ferrite,and polygonal ferrite take over more than 90%.It has also been demonstrated that with the increase in Mn content,the ferrite side plate fraction increases slightly from 5%to 10%and the acicular ferrite fraction shows a tendency of first increasing and then decreasing,which experiences the maximum with the flux containing 30 wt.%*** phenomenon is believed to be controlled by the O and Mn contents in weld metals synergistically.

关键词： Submerged arc welding Transition zone Phase transformation Microstructure