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Optical Remote-sensing Monitoring and Forecasting of Atmospheric Pollution in Huaibei Area, China 被引量:1
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作者 Su-wen Li Pin-hua Xie +2 位作者 En-hua Jiang Yong Zhang hai-feng dai 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2012年第6期739-742,I0004,共5页
Huaibei 是一个精力城市。主要精力消费在 Huaibei 区域带很多地区性的污染的煤。微分光吸收光谱学(DOAS ) 作为光遥感技术被使用了监视氮二氧化物,硫二氧化物和臭氧的地区性的平均集中和库存。DOAS 系统被建立并且适用在 Huaibei 区... Huaibei 是一个精力城市。主要精力消费在 Huaibei 区域带很多地区性的污染的煤。微分光吸收光谱学(DOAS ) 作为光遥感技术被使用了监视氮二氧化物,硫二氧化物和臭氧的地区性的平均集中和库存。DOAS 系统被建立并且适用在 Huaibei 区域监视主要空气污染物质。监视数据从 2011 年 8 月 7 日被获得。监视结果证明在控制污染的大小是有效的,并且污染物质的排出物直到在 Huaibei 区域的国家标准。预言模型也被创造追踪污染的变化趋势。这些将在 Huaibei 区域为环境质量的有效评估提供未加工的数据支持。 展开更多
关键词 光学遥感技术 淮北地区 监测区域 大气污染 差分光学吸收光谱 DOAS系统 空气污染物 预报
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PS Vir:a short-period solar-like contact binary 被引量:1
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作者 Hui-Yu Yuan hai-feng dai Yuan-Gui Yang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2018年第7期45-52,共8页
We present multi-color photometric observations and a one-dimensional spectrum, acquired from March 2016 to May 2017, for the short-period eclipsing binary PS Vir, by using the 2.16-m, 85-cm and 60-cm telescopes at Xi... We present multi-color photometric observations and a one-dimensional spectrum, acquired from March 2016 to May 2017, for the short-period eclipsing binary PS Vir, by using the 2.16-m, 85-cm and 60-cm telescopes at Xinglong station, which is administered by National Astronomical Observatories, Chinese Academy of Sciences. The spectral type was determined as G2V from the one-dimensional spectrum. The photometric solution was reduced from BVRc light curves. The results imply that PS Vir is a W-subtype contact binary with a mass ratio of q - 0.305(zk0.008) and a fill-out factor of f = 14.4(+1.8)%. The orbital period may be undergoing a cyclic oscillation with an ampli-tude of A = 0.0027(~0.0001)d and a modulated period of 11.7(4-0.2) yr, which may result from the light-time effect due to a third body. The lower limit on mass for the assumed component is 0.12 Me. Moreover, the more massive component of PS Vir may be a bit more evolved star as determined from the mass-luminosity diagram. 展开更多
关键词 BINARIES close-binaries eclipsing-stars individual(PS Vir)-stars
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OO Aquilae:a solar-type contact binary with intrinsic light curve changes 被引量:3
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作者 Hua-Li Li Jian-Yan Wei +1 位作者 Yuan-Gui Yang hai-feng dai 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2016年第1期13-22,共10页
New multi-color photometry of the solar-type contact binary OO Aql was obtained in 2012 and2013, using the 60 cm telescope at Xinglong Station of the National Astronomical Observatories, Chinese Academy of Sciences. F... New multi-color photometry of the solar-type contact binary OO Aql was obtained in 2012 and2013, using the 60 cm telescope at Xinglong Station of the National Astronomical Observatories, Chinese Academy of Sciences. From two sets of light curves LC_1 and LC_2, photometric models were performed by using the 2003 version of the Wilson-Devinney code. The overcontact factor of the binary system was determined to be f = 37.0(±0.5)%. The intrinsic variability of this binary occurs in light maxima and minima, which could result from a possible third component and magnetic activity of the late type components. Based on all available light minimum times, the orbital period may change in a complicated mode,i.e., sudden period jumps or continuous period variations. The period of OO Aql may possibly undergo a secular period decrease with a rate of d P /dt =-3.63(±0.30) × 10^(-8)d yr^(-1), superimposed by two possible cyclic variations in the O- C curve. The long-term period decrease may be interpreted as conserved mass transfer from the more massive component to the less massive one. The 21.5-yr oscillation may be attributed to cyclic magnetic activity, and the 69.3-yr one may result from the light-time effect of an unseen tertiary body. 展开更多
关键词 binaries: close -- binaries: eclipsing -- stars: individual (OO Aql)
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A photometric-spectroscopic study of the infrared-excess eclipsing binary V2364 Cyg
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作者 Hui-Yu Yuan Lin-Qiao Jiang +2 位作者 hai-feng dai Shuang Wang Yuan-Gui Yang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2020年第12期307-316,共10页
The eclipsing binary V2364 Cyg is an A7 V-type contact binary with a period of 0.5921 d.We present six spectra from LAMOST and BVRc light curves(LCs),which are simultaneously analyzed to obtain the absolute physical p... The eclipsing binary V2364 Cyg is an A7 V-type contact binary with a period of 0.5921 d.We present six spectra from LAMOST and BVRc light curves(LCs),which are simultaneously analyzed to obtain the absolute physical parameters.The first light maxima are brighter than the second ones by up to 0.m038,0.m036 and 0.m024 for BVRc bands,respectively.These distorted LCs are modeled by a cool spot on the less massive component.Its mass ratio and over-contact degree are q=0.319(±0.004) and f=28.4%(±1.0) % respectively.From the mass-luminosity diagram,the primary component is a normal main-sequence star,while the secondary one is a subgiant star.From the(O-C) curve,the orbital period secularly decreases at a rate dP/dt=-1.62(±0.03) × 10^-7 dyr^-1,which is mainly attributed to mass loss via stellar wind from the binary system.This may result in the observed infrared excess in the W4 band. 展开更多
关键词 stars:circumstellar matter stars:binaries:close stars:individual(V2364 Cyg) mass loss infrared excess
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IU Cancri:a solar-type contact binary with mass transfer
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作者 Hui-Yu Yuan hai-feng dai Yuan-Gui Yang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2019年第6期89-96,共8页
We present new CCD photometry of the solar-type contact binary IU Cnc, which was observed from November 2017 to March 2018 with three small telescopes in China. BV light curves imply that IU Cnc is a W-type contact bi... We present new CCD photometry of the solar-type contact binary IU Cnc, which was observed from November 2017 to March 2018 with three small telescopes in China. BV light curves imply that IU Cnc is a W-type contact binary with total eclipses. The photometric solution indicates that the mass ratio and fill-out factor are q = 4.104 ± 0.004 and f = 30.2%± 0.3%, respectively. From all available light minimum times, the orbital period may increase at a rate of dP/dt =+6.93(4)× 10^-7 d yr^-1, which may result from mass transfer from the secondary component to the primary one. With mass transferring,IU Cnc may evolve from a contact configuration into a semi-detached configuration. 展开更多
关键词 binaries:close-binaries eclipsing-stars individual(IU Cancri)
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Period studies and photometric models for two EB-type binaries EU Hya and AW Vul
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作者 Yuan-Gui Yang Qun Li +1 位作者 Hua-Li Li hai-feng dai 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2016年第2期127-134,共8页
New photometry for two Algol-type binaries, 0.8065 d), was carried out using the 60-cm telescope EU Hya (P = 0.7782 d) and AW Vul (P = at Xinglong station of National Astronomical Observatories, Chinese Academy of... New photometry for two Algol-type binaries, 0.8065 d), was carried out using the 60-cm telescope EU Hya (P = 0.7782 d) and AW Vul (P = at Xinglong station of National Astronomical Observatories, Chinese Academy of Sciences. With the updated Wilson-Devinney code, photometric el- ements were derived from the multi-color light curves. The modeled results indicate that the two systems are near-contact binaries, whose secondary components fill their Roche lobes. The fill-out factors of the primaries are fp = 81.2 (±0.2)% for EU Hya and fp --- 82.4 (±0.3)% for AW Vul. Period analysis implies that there exists a downward parabola with a light-time orbit from the (O - C) curve. This kind of periodic oscillation may be attributed to the light-time orbit effect of a third companion. The long-term period de- crease may be caused by mass and angular momentum loss. When the orbital period decreases, the fill-out factor of fp will increase. Our results indicate that the primaries will also eventually fill their Roche lobes. EU Hya and AW Vul may possibly evolve from semi-detached binaries into contact ones. 展开更多
关键词 eclipsing binaries -- stars individual (EU Hya and AW Vul) -- the third companion
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