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黄芪多糖的化学和药理研究进展

上海中医药大学学报 2000年第3期14卷 61-64,F003页

作者：单俊杰王顺春刘涤胡之璧上海中医药大学中药研究所上海200032

就近年来国内外对黄芪多糖的化学组成及药理作用的研究进行综述。阐述了黄芪多糖的单糖组成、糖链结构 ,以及在免疫调节、保护心肌、降血糖。

关键词：黄芪多糖体液免疫细胞免疫延缓衰老

Global Well-posedness and Global Attractor for Two-dimensional Zakharov-Kuznetsov Equation

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Acta Mathematica Sinica,English Series 2020年第9期36卷 969-1000页

作者： Min jie shan Academy of Mathematics and Systems Science Chinese Academy of SciencesBeijing 100190P.R.China

The initial value problem for two-dimensional Zakharov-Kuznetsov equation is shown to be globally well-posed in H^s(R^2)for all 5/7 详细信息

The initial value problem for two-dimensional Zakharov-Kuznetsov equation is shown to be globally well-posed in H^s(R^2)for all 5/7

关键词： Zakharov-Kuznetsov equation global well-posedness global attractor I-method atomic spaces

Erratum:"Gamma/Hadron Separation Method for the HADAR Experiment"(2024,RAA,24,035007)

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Research in Astronomy and Astrophysics 2024年第7期24卷 273-273页

作者： Yang-Zhao Ren Tian-Lu Chen You-Liang Feng Dan-Zeng Luo-Bu Yi-Qing Guo Cheng Liu Qi Gao Mao-Yuan Liu Xiang-Li Qian Ya-Ping Wang Zi-Hao Zhang Xin-Long Li Qing-Yuan Hou Heng-Jiao Liu Qing-Qian Zhou shan-jie shu The Key aboraory ComicRays(bet Univery)Minitry EucationLhasa 850000ChinaThe Key Laboratory of Cosmic Rays(CTibet University).Ministry of EducationLhasa 850000China Key Laboratory of Particle Astrophysices Instiue of High Energy PhysicsChinese Academy of SciencesBiing 100049China University of Chinese Academy of Sciences Beijing 100049.China School of Inelligent Engineering Shandong Management UniversityJinan 250357China

A possible precession period for superluminal ejection in QSO 3C 279

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Research in Astronomy and Astrophysics 2011年第1期11卷 43-62页

作者： shan-jie Qian National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China

The search for periodic features in fiux variability and superluminal ejection in blazars has been an important subject, which is helpful for providing significant clues to the understanding of the structure and kinematics of relativistic jets （physical processes of acceleration and collimation） and their association with central energy engines （black hole/accretion disk systems）. The wobbling of the ejection position angle of VLBI knots in superluminal sources has been interpreted in terms of the precession of the jet ejection nozzle as one of the alternative interpretations. We study the change with time of the initial position angle of superluminal knots in QSO 3C 279, using VLBI-data collected from the literature spanning more than ～30 yr and propose a jet-nozzle precession model which has very small viewing angles （less than 2°） to fit the long-term trends in both variations in the inner-jet position angle （Chatterjee et al.） and the ejection position angle of the VLBI components. It is shown that an ejection-nozzle precession period of ～25 yr could be appropriate to fit the long-term trend in the variation of the ejection position angle. However, the short-term swings and fluctuations in the ejection position angle cause some uncertainties. We also fit a model to the trajectory of component C4, correcting its non-ballistic motion near the core.

关键词： radio continuum -- quasars -- jets -- kinematics -- individual: 3C 279

Model-fitting of the kinematics of superluminal components in blazar 3C 279

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Research in Astronomy and Astrophysics 2012年第1期12卷 46-62页

作者： shan-jie Qian National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China

A precessing jet-nozzle model with a precession period of about 25 yr has been proposed by Qian to interpret the change with time of the ejection position an- gle of the superluminal components observed using very long baseline interferometry （VLBI） in the blazar 3C 279. We discuss the kinematic properties of six superluminal knots （C3, C4, C7a, C8, C9 and C10） and show that their trajectory, core-distance and apparent speed, derived from VLBI observations, can be consistently well fitted by the model. Their intrinsic Lorentz factors of bulk superluminal motion are thus derived, and the evidence shows no relation between Lorentz factor and the precession phase. Interestingly, for the C7a and C8 knots, the fitted core-distance ranges from ,,～0.1 mas to ～0.4 mas and for knots C9 and C10 from ～0.2mas to ～1.0-1.5 mas. For knot C4, its trajectory and apparent velocity are well fitted in the core-distance range from H1 mas to ～5 mas, taking into account a curvature of the trajectory at core-distance larger than ,,～3 mas. The consistent fitting of the kinematics of these components clearly demonstrates that the amplitude function and collimation param- eter adopted in the precession model are appropriate and applicable for both the in- ner and outer parts of the jet in 3C 279, but in some cases the jet curvature in the outer parts （or deviation from the model trajectory） needs to be seriously taken into consideration. With the exception of C4, the ejection position angles derived from the precession model are consistent with the values measured by VLBI observations （within about 3° - 6°）. Undoubtedly, the consistent interpretation of the kinematics in terms of the precession model for these superluminal components, with their ejection time spanning -～24 yr, significantly expands its applicability and implies that regular patterns of trajectories （or rotating channels） could exist in some periods.

关键词： radio continuum -- galaxies: jets -- galaxies: kinematics -- galaxies:individual (blazar 3C 279)

Model fitting of the kinematics of ten superluminal components in blazar 3C 279

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Research in Astronomy and Astrophysics 2013年第7期13卷 783-802页

作者： shan-jie Qian National Astronomical Observatories Chinese Academy of Sciences

The kinematics of ten superluminal components （C11-C16, C18, C20, C21 and C24） of blazar 3C 279 are studied from VLBI observations. It is shown that their initial trajectory, distance from the core and apparent speed can be well fitted by the precession model proposed by Qian. Combined with the results of the model fit for the six superluminal components （C3, C4, C7a, C8, C9 and C10） already pub-lished, the kinematics of sixteen superluminal components can now be consistently interpreted in the precession scenario with their ejectiontimes spanning more than 25 yr （or more than one precession period）. The results from model fitting show the possible existence of a common precessing trajectory for these knots within a pro- jected core distance of ～0.2-0.4 mas. In the framework of the jet-precession scenario, we can, for the first time, identify three classes of trajectories which are character-ized by their collimation parameters. These different trajectories could be related to the helical structure of magnetic fields in the jet. Through fitting the model, the bulk Lorentz factor, Doppler factor and viewing angle of these knots are derived. It is found that there is no evidence for any correlation between the bulk Lorentz factor of the components and their precession phase （or ejection time）. In a companion paper, the kinematics of another seven components （C5a, C6, C7, C17, C19, C22 and C23） have been derived from model fitting, and a binary black-hole/jet scenario was envisaged. The precession model proposed by Qian would be useful for understanding the kine- matics of superluminal components in blazar 3C 279 derived from VLBI observations, by disentangling different mechanisms and ingredients. More generally, it might also be helpful for studying the mechanism of jet swing （wobbling） in other blazars.

关键词： radio continuum - galaxies jets - galaxies kinematics - galaxies individual (blazar 3C 279)

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Chinese Journal of Astronomy and Astrophysics 2008年第2期8卷 219-229页

作者： shan-jie Qian National Astronomical Observatories Chinese Academy of Sciences Beijing 100012

Correlated radio-optical variations on intraday timescales have been observed （e.g. in BLO 0716＋714） and such radio intraday variability is suggested to have an intrinsic origin. Recently, multi-wavelength observations, simultaneous at radio, mm-submm, optical and hard X-rays, of 0716＋714, show that during a period of intraday/interday variations at radio and mm wavelengths, the apparent brightness temperature of the source exceeded the Compton-limit （-10^12 K） by 2-4 orders of magnitude, but no Compton catastrophe （or no high luminosity of inverse-Compton radiation） was detected. It is also found that the intraday/interday variations at mm-submm wavelengths are consistent with the evolutionary behavior of a standard synchrotron source and for the intraday/interday variations at centimeter wavelengths opacity effects can play a significant role, which is consistent with the interpretation suggested previously by Qian et al. Thus the apparent high brightness temperatures may probably be explained in terms of Doppler boosting effects due to bulk relativistic motion of the source. We will argue a scenario to simulate the correlations between the radio and optical variations on intraday timescales observed in BLO 0716＋714 in terms of a relativistic shock propagating through a jet with a dual structure.

关键词： optical and radio continuum: galaxies -- galaxies: intraday variability -- quasars: individual: BLO 0716+71

Non-ballistic motion and precessing helical trajectory in quasar NRAO 150

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Research in Astronomy and Astrophysics 2016年第1期16卷 175-189页

作者： shan-jie Qian National Astronomical Observatories Chinese Academy of Sciences

NRAO 150 is a very special radio quasar in which prominent non-ballistic superluminal motion has been observed in its inner-jet region. We apply model-fittings to the kinematics of the superluminal knots（trajectory, distance from the core and apparent velocity） in terms of a helical precessing jet-nozzle *** cases are considered in which the angle between the jet axis and the line of sight is assumed to be 6？,3？, 1？, 0.6？ and 0.12？, respectively. It is shown that the superluminal components have intrinsic acceleration in the innermost regions（≤0.2 mas from the core）. The phenomenon of precessing nozzle/trajectory can be understood on the basis of relativistic magnetohydrodynamic theories for relativistic jets.

关键词： radio continuum: galaxies -- galaxies: jets -- galaxies: kinematics -- galaxies: individual(quasar NRAO 150)

Model simulation for periodic double-peaked outbursts in blazar OJ 287: binary black hole plus lighthouse effect

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Research in Astronomy and Astrophysics 2015年第5期15卷 687-712页

作者： shan-jie Qian National Astronomical Observatories Chinese Academy of Sciences

The mechanism of formation for double-peaked optical outbursts observed in blazar OJ 287 is studied. It is shown that they could be explained in terms of a light- house effect for superluminal optical knots ejected from the center of the galaxy that move along helical magnetic fields. It is assumed that the orbital motion of the secondary black hole in the supermassive binary black hole system induces the 12-year quasi-periodicity in major optical outbursts by the interaction with the disk around the primary black hole. This interaction between the secondary black hole and the disk of the primary black hole （e.g. tidal effects or magnetic coupling） excites or injects plas- mons （or relativistic plasmas plus magnetic field） into the jet which form superluminal knots. These knots are assumed to move along helical magnetic field lines to produce the optical double-peaked outbursts by the lighthouse effect. The four double-peaked outbursts observed in 1972, 1983, 1995 and 2005 are simulated using this model. It is shown that such lighthouse models are quite plausible and feasible for fitting the double-flaring behavior of the outbursts. The main requirement may be that in OJ 287 there exists a rather long （～40-60 pc） highly collimated zone, where the lighthouse effect occurs.

关键词： optical continuum -- galaxies jets -- galaxies kinematics -- galaxies variability -- galaxies individual (blazar OJ 287)