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Lunar-based Ultraviolet Telescope study of the well-known Algol-type binary TW Dra

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Research in Astronomy and Astrophysics 2016年第6期16卷 93-98页

作者： wen-ping liao Sheng-Bang Qian Miloslav Zejdat Li-Ying Zhu Lin-Jia Li Yunnan Observatories Chinese Academy of Sciences Kunming 650216 China Key Laboratory of the Structure and Evolution of Celestial Objects Chinese Academy of Sciences Kunming 650216China University of Chinese Academy of Sciences Beijing 100049 China Department of Theoretical Physics and Astrophysics Masaryk University Kotlarska 2 CZ-611 37 Brno Czech Republic

By using the Lunar-based Ultraviolet Telescope （LUT） from 2014 December 2 to December 4, the first near-UV light curve of the well-known Algol-type binary TW Dra is reported, which is analyzed with the 2013 version of the W-D code. Our solutions confirmed that TW Dra is a semi-detached binary system where the secondary component fills its Roche lobe. The mass ratio and a high inclination are obtained （q = 0.47, i = 86.68°）. Based on 589 available data spanning more than one century, the complex period changes are studied. Secular increase and three cyclical changes are found in the corresponding orbital period analysis. The secular increase changes reveal mass transfer from the secondary component to the primary one at a rate of 6.8 × 10-7 M yr-1. One large cyclical change of 116.04 yr may be caused by disturbance of visual component ADS 9706B orbiting TW Dra （ADS 9706A）, while the other two cyclical changes with shorter periods of 22.47 and 37.27 yr can be explained as the result of two circumbinary companions that are orbiting around TW Dra, where the two companions are in simple 3 ： 5 orbit-rotation resonances. TW Dra itself is a basic binary in a possible sextuple system with the configuration （1 ＋ 1）＋（1 ＋ 1）＋（1 ＋ 1）, which further suggests that multiplicity may be a fairly common phenomenon in close binary systems.

关键词： stars: binaries: close -- stars: binaries: eclipsing -- stars: individual (TW Draco)

High amplitude δ Scuti star BO Lyn with evidence of a late A-type companion in an elliptical orbit

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Research in Astronomy and Astrophysics 2018年第1期18卷 119-126页

作者： Lin-Jia Li Sheng-Bang Qian Jia Zhang Li-Ying Zhu wen-ping liao Yunnan Observatories Chinese Academy of Sciences Kunming 650216 China Key Laboratory of the Structure and Evolution of Celestial Objects Chinese Academy of Sciences Kunming 650216 China Center for Astronomical Mega-Science Chinese Academy of Sciences Beijing 100012 China University of Chinese Academy of Sciences Beijing 100049 China

We present 145 times of light maximum for high amplitude δ Scuti star BO Lyn based on several sky surveys（CRTS,DASCH,NSVS,OMC and Super WASP）and our photometric *** with the data in literature,a total of 179 times of light maximum are used to analyze the O-C diagram of BO *** find that it can be described by an upward parabolic component and a periodic variation with a period of 34.5±0.1 *** latter could be caused by the light travel time effect as a result of an additional companion orbiting in a highly elliptical orbit（e=0.64±0.03）.Our study indicates that the companion’s luminosity cannot be ignored,and it should be a late A-type main-sequence *** long-term period change of BO Lyn is also detected,and its value,1.52±0.26×10^（-3）d Myr^（-1）,is consistent with evolutionary *** suggest that more spectroscopic and photometric observations are needed in the future to confirm the nature of the BO Lyn system.

关键词： techniques:photometric stars:variables:δ Scuti stars:individual(BO Lyn)

The first photometric investigations of the G-type shallow contact binary IO Cnc

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Research in Astronomy and Astrophysics 2021年第2期21卷 133-141页

作者： wen-ping liao Lin-Jia Li Xiao Zhou Qi-Shan Wang Yunnan Observatories Chinese Academy of SciencesKunming 650216China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of SciencesKunming 650216China Center for Astronomical Mega-Science Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China

IO Cnc was classified to be a new G-type(G0)W UMa-type eclipsing binary *** first multicolor photometric solutions show that IO Cnc is a new W-subtype shallow contact binary with a fill-out factor of f=16.1%and a low mass ratio of q=3.12(or 1/q=0.32).During orbital period investigations,a cyclic variation and a downward parabolic variation with a rate of(-1.28±0.43)×10^(-7) d yr^(-1) was discovered in the observed–calculated(O-C)*** cyclic variation was analyzed by the light travel time effect(LTTE)via a potential red dwarf companion star,an orbital semi-major axis shorter than 4.88±0.82 AU was ***,we collect physical parameters of a sample of 50 G-type shallow contact binaries(f≤20%),it is suggested that most of the G-type shallow contact binaries are undergoing a longterm and periodic orbital period changes,especially more systems show long-term *** long-term orbital period decrease indicates that IO Cnc is in a mass transferring from the more massive component to the less massive *** the long-term decrease of the orbital period,this shallow contact binary will evolve into a deeper contact one.

关键词： stars binaries close-stars binaries eclipsing-stars individual(IOCnc)-stars solar-type-stars evolution

NSVS 01286630:a detached binary with a close-in companion

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Research in Astronomy and Astrophysics 2018年第9期18卷 123-132页

作者： Bin Zhang Sheng-Bang Qian Nian-ping Liu wen-ping liao Li-Ying Zhu Ai-Jun Dong Qi-Jun Zhi Yunnan Observatories Chinese Academy of SciencesKunming 650216China Key Laboratory of the Structure and Evolution of Celestial Objects Chinese Academy of SciencesKunming 650216China University of Chinese Academy of Sciences Beijing 100049China School of Physics and Electronic Science Guizhou Normal UniversityGuiyang 550001China

New photometric observations of NS VS 01286630 were performed and two sets of fourcolor（B, V, Rc, Ic） light curves（LCs） were obtained. Using the 2013 version of the Wilson-Devinney（W-D） code, we analyzed these data. The photometric solutions reveal that NS VS 01286630 is an active detached eclipsing binary（EB） with a high orbital inclination（nearly 90°）. Remarkably, the temperature of the primary component（the hotter star） is higher than the secondary one, but the value of mass ratio q（M2/M1）for NS VS 0128663 is more than 1, which can be explained in that the surface of the secondary component of NSVS 01286630 is covered with big cool starspots. Based on our new CCD mid-eclipse times and the data published until now, variations in the mid-eclipse times were reanalyzed in detail using a weighted least-squares method. It is discovered that the（O-C） diagram of the system shows a cyclic oscillation with a period of 3.61 yr and an amplitude of 0.001 d. The cyclic variation may be caused by the light-travel time effect（LTTE） due to the presence of a third companion, whose mass we calculated as M3 sin（i3） =0.11 M（⊙）. The third body may affect the orbital evolution of the central binary system by transferring angular momentum.

关键词： stars binaries close- stars binaries eclipsing-stars individual (NSVS 01286630)

More than two hundred and fifty thousand spectroscopic binary or variable star candidates discovered by LAMOST

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Research in Astronomy and Astrophysics 2019年第5期19卷 15-26页

作者： Sheng-Bang Qian Xiang-Dong Shi Li-Ying Zhu Lin-Jia Li Jia Zhang Er-Gang Zhao Zhong-Tao Han Xiao Zhou Xiao-Hui Fang wen-ping liao Yunnan Observatories Chinese Academy of Sciences Key Laboratory of the Structure and Evolution of Celestial Objects Chinese Academy of Sciences Center for Astronomical Mega-Science Chinese Academy of Sciences University of Chinese Academy of Sciences

About 786.4 thousand stars were observed by LAMOST twice or more during the first stage of its spectroscopic survey. The radial velocity differences for about 256 thousand targets are larger than10 km s^(-1) and they are possible spectroscopic binary or variable candidates(SBVCs). It is shown that most SBVCs are slightly metal poorer than the Sun. There are two peaks in the temperature distribution of SBVCs around 5760 K and 4870 K, while there are three peaks in the distribution of the gravitational acceleration at 2.461, 4.171 and 4.621 cm s^(-2). The locations of SBVCs on the [Fe/H]-T, [Fe/H]-log g, log g-T and H-R diagrams are investigated. It is found that the detected SBVCs could be classified into four groups. The first group has higher log g～4.621 and lower T ～ 4870 K which are mainly cool red dwarf binaries. The second group of SBVCs has logg around 4.171 cm s^(-2) that includes binaries and pulsating stars such as δSet and γ Dor variables. The gravitational accelerations of the third group of SBVCs are higher and some of them are below the zero-age main sequence. They may be contact binaries in which the primary components are losing energy to the secondaries in the common envelopes and are at a special stellar evolutionary *** last group is composed of giants or supergiants with log g around 2.461 cm s^(-2) that may be evolved pulsating stars. One target(C134624.29+333921.2) is confirmed as an eclipsing binary with a period of 0.65 days. A preliminary analysis suggests that it is a detached binary with a mass ratio of 0.46. The primary fills its critical Roche lobe by about 89%, indicating that mass transfer will occur between the two components.

关键词： stars fundamental parameters-stars binaries spectroscopic-stars:oscillations-stars:binaries eclipsing-stars variables other

Investigation on ignition characteristics of charring conductive polymers stimulated by electric energy

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Chinese Journal of Aeronautics 2024年第10期37卷 68-82页

作者： Zhiyuan ZHANG Hanyu DENG wenhe liao Yantao PU ping CAO School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing 210094China Anhui Hongxing Electrical Polytron Technologies Inc. Hefei 231135China

The arc ignition based on charring conductive polymers has advantages of simple structure,low ignition power consumption and restart capacity,which bringing it broadly application prospect in hybrid propulsion system of micro/nano *** order to optimize the performance of arc ignition system,it is essential to have a deeper understanding of the ignition processes and ignition characteristics of charring conductive *** this paper,the thermal decomposition,electrical conductivity and thermal conductivity characteristics of charring conductive polymers with different conductive additives and matrix materials were comprehensively *** experimental investigation was conducted to determine the ignition behaviors and characteristics of different charring conductive polymers in a visual ignition *** experiment result showed that the ignition delay and external energy required for ignition are negatively correlated with voltage and initial temperature of the ignition grain,but positively correlated with oxidizer flow *** with charring conductive polymers containing multi-walled carbon nanotube,the ignition delay of charring conductive polymers with carbon black is significantly higher and the pyrolysis time is relatively ***,the ignition and initial flame propagation of charring conductive polymers with carbon black is more violent and more inclined to carbon particle ***,the restart characteristic of different charring conductive polymers was *** ignition delay and external energy required for ignition of different charring conductive polymers all reduced with the increasing of the number of ***,the ignition characteristics would not change a lot after repeated ignition.

关键词： Micro/nano satellite hybrid rocket motors Arc ignition Charring conductive polymer Ignition process Ignition characteristic Restart characteristic

Carbon steel anticorrosion performance and mechanism of sodium lignosulfonate

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Rare Metals 2024年第1期43卷 356-365页

作者： Bo-Kai liao Rui-Xuan Quan ping-Xian Feng Huan Wang Wei Wang Li Niu School of Chemistry and Chemical Engineering Guangzhou Key Laboratory of Sensing Materials and DevicesJoint Institute of Guangzhou University and Institute of Corrosion Science and TechnologyGuangzhou UniversityGuangzhou 510006China

Lignin is a typical biological macromolecule with a three-dimensional network structure and abundant functional groups. It has excellent ionic complexation ability and amphiphilic molecular structure *** this study, the carbon steel anticorrosion performance of sodium lignosulfonate(SLS) in an acid solution was evaluated using the weight loss method, electrochemical measurements, scanning vibration electrode technique(SVET), and surface characterization methods. SLS exhibited excellent corrosion inhibition efficiency for Q235carbon steel in 1 mol·L^(-1) HCl, reaching a maximum value of 98%. A low SLS concentration of 20 mg·L^(-1) resulted in the maximum corrosion inhibition efficiency, which remained nearly constant at higher SLS *** SVET test demonstrated that the formation of an SLS adsorption film can impede corrosion. This study confirms the significance of the application of green biomass resources in the field of metal corrosion protection and green functional materials.

关键词： Lignin Sodium lignosulfonate Corrosion inhibitor Carbon Steel

Molecular mechanisms underlying the negative effects of transient heatwaves on crop fertility

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Plant Communications 2024年第9期5卷 101-115页

作者： Qian Yao ping Li Xin Wang Shuhua liao Pu Wang Shoubing Huang College of Agronomy and Biotechnology China Agricultural UniversityBeijing 100193China

Transient heatwaves occurring more frequently as the climate warms,yet their impacts on crop yield are severely underestimated and even *** lasting only a few days or even hours during sensitive stages,such as microgametogenesis and flowering,can significantly reduce crop yield by disrupting plant *** advances in multi-omics and GWAS analysis have shed light on the specific organs(e.g.,pollen,lodicule,style),key metabolic pathways(sugar and reactive oxygen species metabolism,Ca2+homeostasis),and essential genes that are involved in crop responses to transient heatwaves during sensitive *** review therefore places particular emphasis on heat-sensitive stages,with pollen development,floret opening,pollination,and fertilization as the central narrative *** multifaceted effects of transient heatwaves and their molecular basis are systematically reviewed,with a focus on key structures such as the lodicule and tapetum.A number of heat-tolerance genes associated with these processes have been identified in major crops like maize and *** mechanisms and key heat-tolerance genes shared among different stages may facilitate the more precise improvement of heat-tolerant crops.

关键词： heat stress floret fertility pollen pollen tube growth seed set molecular mechanism

Ferrihydrite transformation impacted by coprecipitation of lignin:Inhibition or facilitation?

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Journal of Environmental Sciences 2024年第5期139卷 23-33页

作者： Lin Liu Zhihui Yang Weichun Yang wen Jiang Qi liao Mengying Si Feiping Zhao School of Metallurgy and Environment Central South UniversityChangsha 410083China Chinese National Engineering Research Center for Control&Treatment of Heavy Metal Pollution(CNERC-CTHMP) Changsha 410083China

Lignin is a common soil organic matter that is present in soils,but its effect on the transformation of ferrihydrite(Fh)remains *** matter is generally assumed to inhibit Fh ***,lignin can reduce Fh to Fe(Ⅱ),in which Fe(Ⅱ)-catalyzed Fh transformation ***,the effects of lignin on Fh transformation were investigated at 75℃ as a function of the lignin/Fh mass ratio(0-0.2),pH(4-8)and aging time(0-96 hr).The results of Fh-lignin samples(mass ratios=0.1)aged at different pH values showed that for Fh-lignin the time of Fh transformation into secondary crystalline minerals was significantly shortened at pH 6 when compared with pure Fh,and the Fe(Ⅱ)-accelerated transformation of Fh was strongly dependent on *** pH 6,at low lignin/Fh mass ratios(0.05-0.1),the time of secondary mineral formation decreased with increasing lignin *** high lignosulfonate-content material(lignin:Fh=0.2),Fh did not transform into secondary minerals,indicating that lignin content plays a major role in Fh *** addition,lignin affected the pathway of Fh transformation by inhibiting goethite formation and facilitating hematite *** effect of coprecipitation of lignin on Fh transformation should be useful in understanding the complex iron and carbon cycles in a soil environment.

关键词： Ferrihydrite transformation Lignin Hematite Goethite Fe(Ⅱ)-catalyzed Reactive Fe(Ⅲ)species