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New CCD photometry of asteroid(1028)Lydina

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Research in Astronomy and Astrophysics 2012年第12期12卷 1714-1722页

作者： yi-bo wang Xiao-Bin wang National Astronomical Observatories/Yunnan Observatory Chinese Academy of SciencesKunming 650011China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of SciencesKunming 650011China Graduate University of Chinese Academy of Sciences Beijing 100049China

New CCD photometric observations for asteroid（1028）Lydina,carried out with the 1-m and 2.4-m telescopes at Yunnan Observatory from 2011 December 19 to 2012 February 3,are *** the new light curves,the rotation period of 11.680±0.001 hours is derived with the Phase Dispersion Minimization（PDM） *** addition,using the Amplitude-Aspect method,the elementary results of the pole orientation of asteroid（1028）Lydina are obtained：λp=111°＋4°-4°,βp=31°＋4°-5°. Meanwhile,the axial ratios of the tri-axial ellipsoid are estimated：a/b=1.77＋0.10 -0.08 and b/c=1.17＋0.07 -0.09 .

关键词： asteroids:photometric-observation:rotation period-pole orienta- tion:tri-axial ellipsoid

Study of photometric phase curve with new brightness model:refining phase function system parameters of asteroid(107)Camilla

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Research in Astronomy and Astrophysics 2016年第9期16卷 117-122页

作者： yi-bo wang Xiao-Bin wang Ao wang Yunnan Observatories Chinese Academy of SciencesKunming 650011China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of SciencesKunming 650011China

We characterize the morphology of the photometric phase curve model of an asteroid with a three- parameter magnitude phase function H - G1 - G2 system by considering the effect of brightness variation arising from a triaxial ellipsoid representing the asteroid＇s shape. Applying this new model and a Markov Chain Monte Carlo method, we refine the photometric phase curve of asteroid （107） Camilla and obtain its absolute magnitude H = 7.026-0.054^＋0.052 mag, and phase function parameters G1=0.489-0.044^＋0.043 and G2 = 0.259-0.023^＋***, we also determine （107） Camilla＇s orientation of pole （74.1°-4.5°^＋4.3°,50.2°-5.0°^＋5.4°）. with rotational period of 4.843928-0.000001^＋0.000001 h, and axial ratios a/b ： 1.409-0.020^＋0.020 And b/c =1.249-0.060^＋0.063. Furthermore, according to the values of phase function parameters G1 and G2, we infer that asteroid （107） Camilla is an X-type asteroid.

关键词： minor planets, asteroids general phase curve -- minor planets, asteroids individual (107)Camilla -- techniques photometric

Study of photometric phase curve:assuming a cellinoid ellipsoid shape for asteroid(106)Dione

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Research in Astronomy and Astrophysics 2017年第9期17卷 61-70页

作者： yi-bo wang Xiao-Bin wang Donald E Pray Ao wang Yunnan Observatories Chinese Academy of SciencesKunming 650216China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of SciencesKunming 650216China Center for Astronomical Mega-Science Chinese Academy of SciencesBeijing 100012China Sugarloaf Mountain Observatory South DeerfieldMA 01373USA

We carried out new photometric observations of asteroid （106） Dione at three apparitions （2004, 2012 and 2015） to understand its basic physical properties. Based on a new brightness model, new photometric observational data and published data of （106） Dione were analyzed to characterize the morphology of Dione＇s photometric phase curve. In this brightness model, a cellinoid ellipsoid shape and three-parameter （H, G1, G2） magnitude phase function system were involved. Such a model can not only solve the phase function system parameters of （106） Dione by considering an asymmetric shape of an asteroid, but also can be applied to more asteroids, especially those without enough photometric data to solve the convex shape. Using a Markov Chain Monte Carlo （MCMC） method, Dione＇s absolute magnitude of H = 7.66＋0.03-0.03 mag, and phase function parameters G1 = 0.682＋0.077-0.077 and G2 = 0.081＋0.042-0.042 were obtained. Simultaneously, Dione＇s simplistic shape, orientation of pole and rotation period were also determined preliminarily.

关键词： asteroids general photometric phase curve -- asteroids individual (106) Dione - techniques: photometric - Markov Chain Monte Carlo method

Light curve inversion of asteroid(585)Bilkis with Lommel-Seeliger ellipsoid method

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Research in Astronomy and Astrophysics 2016年第12期16卷 19-26页

作者： Ao wang Xiao-Bin wang Karri Muinonen Xianming L.Han yi-bo wang Yunnan Observatories Chinese Academy of SciencesKunming 650011China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of SciencesKunming 650011China University of Chinese Academy of Sciences Beijing 100049China Department of Physics University of HelsinkiGustaf Hallstromin katu 2aEO.Box 64FI-00014 U.HelsinkiFinland Finnish Geospatial Research Institute Geodeetinrinne 2FI-02430 MasalaFinland Department of Physics and Astronomy Butler UniversityIndianapolisIN 46208USA

The basic physical parameters of asteroids, such as spin parameters, shape and scattering parameters, can provide us with information on the formation and evolution of both the asteroids themselves and the entire solar system. In a majority of asteroids, the disk-integrated photometry measurement constitutes the primary source of the above knowledge. In the present paper, newly observed photometric data and existing data on（585） Bilkis are analyzed based on a Lommel-Seeliger ellipsoid model. With a Markov chain Monte Carlo（MCMC） method, we have determined the spin parameters（period, pole orientation）and shape（b/a, c/a） of（585） Bilkis and their uncertainties. As a result, we obtained a rotational period of 8.5738209 h with an uncertainty of 9×10^-7h, and derived a pole of（136.46°, 29.0°） in the ecliptic frame of J2000.0 with uncertainties of 0.67°and 1.1°in longitude and latitude respectively. We also derived triaxial ratios b/a and c/a of（585） Bilkis as 0.736 and 0.70 with uncertainties of 0.003 and 0.03 respectively.

关键词： asteroids -- photometric observation -- spin parameter -- shape -- MCMC method

Construction of Aniline Trimer Based Conjugated Polymers through Schiff Base Reaction and Their Use as Feedstock for Infrared Stealth Coatings

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Chinese Journal of Polymer Science 2023年第6期41卷 851-858,I0005页

作者： Xiang-Yu Li Li-Shuai Zong yi-bo wang Qi Cao Jin-Yan wang Xi-Gao Jian State Key Laboratory of Fine Chemicals Liaoning High Performance Resin Engineering Research CenterDepartment of Polymer Science&EngineeringDalian University of TechnologyDalian 116024China

In order to meet the demand for infrared stealth materials in the military field,conjugated polymers containing Schiff base moieties were designed and *** dialdehyde monomers were introduced and their effect on the comprehensive properties were systematically *** resulted polymers could be cast in solution to prepare polymer *** coatings exhibited high thermal stability up to 400℃ at 5%weight loss,and excellent mechanical performance with high Young’s modulus and *** infrared emissivity values varied from 0.587 to 0.627 at wavelength of 8-14μm and ranged from 0.595 to 0.609 at wavelength of 2-22μ***,it was found that the ATTPAL structure with carbazole moieties had a lower band gap and better electrical conductivity by photoelectric test and DFT theoretical ***,the infrared emissivity value of ATTPAL coating was the lowest compared with p-phenyl and pyridyl containing analogues,suggesting it was potential material for the future development of infrared stealth *** combined results showed that reducing the band gap and improving the electrical conductivity of the structure were both beneficial to the reduction of infrared *** would positively provide new ideas for the design of infrared stealth materials.

关键词： materials Schiff conductivity

Non-artifact vector P- and S-wave separation for elastic reverse time migration

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Petroleum Science 2022年第6期19卷 2695-2710页

作者： Xi-Yan Zhou Xu Chang yi-bo wang Xiao-Tao Wen Jia-Chun You Chang Sun Key Laboratory of Earth Exploration and Information Techniques Chengdu University of TechnologyChengdu610059SichuanChina College of Geophysics Chengdu University of TechnologyChengdu610059SichuanChina Key Laboratory of Shale Gas and Geoengineering Institute of Geology and GeophysicsChinese Academy of SciencesBeijing100029China Key Laboratory of Petroleum Resource Research Institute of Geology and GeophysicsChinese Academy of SciencesBeijing100029China

Elastic reverse time migration(RTM)uses the elastic wave equation to extrapolate multicomponent seismic data to the subsurface and separate the elastic wavefield into P-and S-waves.P-and S-wave separation is a necessary step in elastic RTM to avoid crosstalk between coupled ***,the current curl-divergence operator-based separation method has a polarity reversal problem in PS imaging,and vector separation methods often have separation artifacts at the interface,which affects the quality of the imaging *** propose a non-artifact P-and S-wave separation method based on the first-order velocity-strain *** equation is used for wavefield extrapolation and separation in the first-order staggered-grid finite-difference scheme,and the storage and calculation amounts are consistent with the classical first-order velocity-stress *** separation equation does not calculate the partial derivatives of the elastic parameters,and thus,there is no artifact in the separated Pand *** wavefield extrapolation,the dynamic characteristics of the reflected wave undergo some changes,but the transmitted wavefield is accurate;therefore,it does not affect the dynamic characteristics of the final migration *** numerical examples of 2 D simple models,part SEAM model,BP model,and 3 D 4-layer model,different wavefield separation methods and corresponding elastic RTM imaging results are *** found that the velocity-strain based elastic RTM can image subsurface structures well,without spike artifacts caused by separation artifacts,and without polarity reversal phenomenon of the PS imaging.

关键词： Multicomponent Elastic RTM P-and S-Wave separation Separation artifacts Decoupled velocity-strain equations

2D Janus polymer nanosheets for enhancing oil recovery:From material ppreparation to property evaluation

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Petroleum Science 2023年第3期20卷 1584-1597页

作者： Hao Shen Zi-Hao Yang Guan-Zhong wang yi-Lin Xiong Qi-Chao Lv Qi Cao Qi-Qi Niu yi-bo wang Zhao-xia Dong Unconventional Petroleum Research Institute China University of Petroleum(Beijing)Bejing102249China Sinopec Zhenhai Refining and Chemical Company Ningbo315207ZhejiangChina Shenzhen Institute of Advanced Technology Chinese Academy of SciencesShenzhen518055GuangdongChina School of Energy Resources China University of Geosciences(Bejing)Bejing100083China

Janus amphiphilic polymer nanosheets(JAPNs)with anisotropic morphology and distinctive perfor-mance have aroused widespread ***,due to the difficulty in synthesis and poor dispersion stability,JAPNs have been scarcely reported in the field of enhancing oil recovery(EOR).Herein,a kind of organic-based flexible JAPNs was prepared by paraffin emulsion *** lateral sizes of JAPNs were ranging from hundreds of nanometers to several micrometers and the thickness was about 3 *** organic-based nanosheets were equipped with remarkably flexible structures,which could improve their injection *** dispersion and interfacial properties of JAPNs were studied *** modification of crosslinking agent containing multiple amino groups,the JAPNs had excellent hydro-philicity and salt resistance compared with conventional inorganic or composite *** settling time of nanosuspension with NaCl and CaCl_(2) at a low salinity of 1000 mg/L was over 240 *** value could also remain 124 h under the salinity of 10,000 mg/L *** the dual functionalities of Janus amphiphilic nature and nanoparticles'Pickering effect,JAPNs could change rock wettability and form emulsions as"colloidal surfactants",In particular,a new technology called optical microrheology was pioneered to explore the destabilization state of nanosuspensions for the first *** precipitation lagged behind aggregation,especially for stable suspension systems,the onset of the unstable behavior was difficult to be detected by conventional methods,which should be the indicator of reduced effec-tiveness for nanofluid *** addition,the oil displacement experiments demonstrated that the JAPNs could enhance oil recovery by 17.14%under an ultra-low concentration of 0.005%and were more suitable for low permeability *** findings can help for a better understanding of the material preparation of polymer *** also hope that this study could shed more light

关键词： 2D materials Polymer nanosheets Enhance oil recovery Janus nature Amphiphilic property

Evolution of Cenozoic sedimentary architecture in Central and Southern South China Sea basins

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Journal of Palaeogeography 2024年第1期13卷 35-53页

作者： Wu Tang Xiao-Jun Xie yi-bo wang Lian-Qiao Xiong Jia Guo Xin Li China National Offshore Oil Corporation Research Institute Beijing 100028China

The Central and Southern South China Sea(CSSCS) has a complex tectonic dynamic background and abundant oil and gas resources, which has always been a hot topic of academic and industrial ***, systematic analyses are still lacking regarding its sediment filling structure and evolution, mostly due to limited borehole penetration and poor quality of seismic reflection data for deeply buried sequences. No consensus has been reached yet on the sedimentary infilling processes, which impeded the reconstruction of the palaeogeography of Southeast Asia and the oil-and-gas exploration undertakings. Here, we illustrate the Cenozoic sedimentary evolution of the CSSCS region by synthesizing relevant data from previous literature and our own observations and displaying the evolution of depositional systems in sequential reconstructions. Besides, the controlling factors of preferred sedimentary scenarios in the CSSCS incorporate the latest interpretations of the spreading of South China Sea(SCS) as well as the demise of the hypothetical Proto-South China Sea(PSCS). The results show that there are three types of sedimentary basins in the CSSCS(foreland,strike-slip, and rift basins) with different sedimentary filling structures. The foreland basins formed a depositional pattern of ‘transition from deep water to shallow water environments', dominated by deep-water depositional systems which were formed before the Early Oligocene with submarine fans developed. Later,the foreland basins were gradually dominated by shallow-water depositional systems with deltas and shallow marine facies. The strike-slip basins showed the depositional architecture of ‘transition from lake to marine environments', i.e. the basins were dominated by lacustrine deposits during the Eocene and evolved into the marine depositional environment since Oligocene with delta developed in the western part of the basin. The depositional evolution of rift basins illustrated the characteristics of 'transiti

关键词： Central and Southern South China Sea Sedimentary filling Main controlling factors Proto-South China Sea South China Sea

Probing into the Possible Range of the U bosonic Coupling Constants in Neutron Stars Containing Hyperons

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Research in Astronomy and Astrophysics 2023年第5期23卷 180-189页

作者： Yan Xu Bin Diao yi-bo wang Xiu-Lin Huang Xing-Xing Hu Zi Yu Changchun Observatory National Astronomical ObservatoriesChinese Academy of SciencesChangchun 130117China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China College of Science Nanjing Forestry UniversityNanjing 210037China

The range of the U bosonic coupling constants in neutron star matter is a very interesting but still unsolved problem which has multifaceted influences in nuclear physics,particle physics,astrophysics and *** combination of the theoretical numerical simulation and the recent observations provides a very good opportunity to solve this *** the present work,the range of the U bosonic coupling constants is inferred based on the three relations of the mass–radius,mass-frequency and mass-tidal deformability in neutron stars containing hyperons using the GM1,TM1 and NL3 parameter sets under the two flavor symmetries of SU(6)and SU(3)in the framework of the relativistic mean field *** with observations from PSRs J1614-2230,J0348+0432,J2215-5135,J0952-0607,J0740+6620,J0030-0451,J1748-2446ad,XTE J1739-285,GW170817 and GW190814 events,our numerical results show that the U bosonic coupling constants may tend to be within the range from 0 to 20 GeV^(-2)in neutron star containing ***,the numerical results of the three relations obtained by the SU(3)symmetry are better in accordance with observation data than those obtained by the SU(6)*** results will help us to improve the strict constraints of the equation of state for neutron stars containing hyperons.

关键词： stars neutron-stars interiors-stars luminosity function-mass function-stars massive-dense matter-equation of state-gravitational waves