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GENERALIZED THEORY OF NONLINEAR AND UNSTEADY MECHANICS AND APPLICATIONS TO PARTICLE PHYSICS
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作者 杨文熊 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1995年第1期27-35,共9页
In this paper we consider that the momentum of a free particle motion withhigh-level speed presenting nonlinear effects may be expanded by using Laurent seriesand then obtain the complete expression of nonlinear and u... In this paper we consider that the momentum of a free particle motion withhigh-level speed presenting nonlinear effects may be expanded by using Laurent seriesand then obtain the complete expression of nonlinear and unsteady momentum. These nonlinear and unsieady phenoniena of high-level speed may further expand to the theory of kinematics and it may be determined by Fredholm's integral equation of the first kind. In addition, according to the nonlinear and unsteady momentum obtained the relations of the nonlinear mechanics equations .work and energy, mass and energymay be derived.Finaly .this paper also calculates those experimental results which done in particle physics for mu-mesons u±and fast neutrons n, these results are in agreement with data perfectly. 展开更多
关键词 theory of generalized nonlinear mechanics characteristic speed.Laurent senes particle physics.μ±meson fast neutron
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CLIFFORD ALGEBRA,THEORY OF ITS FUNCTION AND THEIR APPLICATION TO MECHANICS
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作者 黄思训 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1989年第9期853-866,共14页
As is Wellknown in both elastic mechanics andfluid mechanics, the plane problems are more convenient than space problems. One of the causes is that there has been a complete theory about the complex Junction and the a... As is Wellknown in both elastic mechanics andfluid mechanics, the plane problems are more convenient than space problems. One of the causes is that there has been a complete theory about the complex Junction and the analytic junction, hut in space problems, the case is quite different.We have no effective method to deal with these problems. In this paper, we first introduces general theories of Clifford algebra. Then we emphatically explain Clifford algebra in three dimensions and establish theories of regular Junction in three dimensions analogically to analytic function in plane. Thus we extend some results of plane problem-la three dimensions or high dimensions. Obviously, it is very important for elastic and fluid mechanics. But because Clifford algebra is not a commutative algebra, we can't simply extend the results of two dimensions to high dimensions. The left problems are yet to be found out. 展开更多
关键词 CLIFFORD ALGEBRA theory OF ITS FUNCTION AND THEIR APPLICATION TO mechanics
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Conclusions in Theory and Practice for Advancing the Applications of Cable-Driven Mechanisms 被引量:3
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作者 Bin Zi Yuan Li 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2017年第4期763-765,共3页
The theoretical research of cable-driven mechanisms is developed with its broad applications. The first prototype of cable-driven mechanisms is RoboCrane, which was developed by the National Institute of Standards and... The theoretical research of cable-driven mechanisms is developed with its broad applications. The first prototype of cable-driven mechanisms is RoboCrane, which was developed by the National Institute of Standards and Technology (NIST). Then many excellent properties were developed and they have a variety of applications such as aerospace, aircraft and automobile industries [1]. Example application for RoboCrane in the field of aircraft mainte- nance is equipped with a quick-change mechanism to remove the robot arm remotely. 展开更多
关键词 In MORE Conclusions in theory and Practice for Advancing the Applications of Cable-Driven Mechanisms
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MULTIPLE SCATTERING THEORY OF EFFECTIVE MECHANICAL PROPERTIES OF INHOMOGENEOUS MEDIA
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作者 南策文 袁润章 +1 位作者 张清杰 蔡克峰 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 1993年第4期13-23,共11页
The rate of hydrothermal reaction of SiO_2 and/or A1_2O_3 in the system of CaO-Al_2O_3-SiO_2-H_2O at 200℃ and the factors which influence the reactions are investigated by determining the reaction ratio.The rate of r... The rate of hydrothermal reaction of SiO_2 and/or A1_2O_3 in the system of CaO-Al_2O_3-SiO_2-H_2O at 200℃ and the factors which influence the reactions are investigated by determining the reaction ratio.The rate of reactions depends on the reactive activities of raw materials, initial composition of mixture and relative activity of SiO_2 and A12O3. The hydrothermal reaction can be accelerated by sodium hydroxide,in the case of silica,which has low activity, this is quite obvious. 展开更多
关键词 CPA MULTIPLE SCATTERING theory OF EFFECTIVE MECHANICAL PROPERTIES OF INHOMOGENEOUS MEDIA ATA
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From Black Holes to Information Erasure: Uniting Bekenstein’s Bound and Landauer’s Principle
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作者 Boris Menin 《Journal of Applied Mathematics and Physics》 2023年第8期2185-2194,共10页
This research aims to integrate Bekenstein’s bound and Landauer’s principle, providing a unified framework to understand the limits of information and energy in physical systems. By combining these principles, we ex... This research aims to integrate Bekenstein’s bound and Landauer’s principle, providing a unified framework to understand the limits of information and energy in physical systems. By combining these principles, we explore the implications for black hole thermodynamics, astrophysics, astronomy, information theory, and the search for new laws of nature. The result includes an estimation of the number of bits stored in a black hole (less than 1.4 × 10<sup>30</sup> bits/m<sup>3</sup>), enhancing our understanding of information storage in extreme gravitational environments. This integration offers valuable insights into the fundamental nature of information and energy, impacting scientific advancements in multiple disciplines. 展开更多
关键词 Astrophysics and Astronomy Bekenstein Bound Black Hole Thermodynamics Information and Energy Limits Information theory and Quantum mechanics Landauer’s Principle
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ELECTRIC FIELD EFFECTS ON YOUNG'S MOLULUS OF NANOWIRES 被引量:2
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作者 Xiaojing Zheng Li Qiao 《Acta Mechanica Solida Sinica》 SCIE EI 2009年第6期511-523,共13页
As an important component of nanodevices and nanomachine constructions, the mechanical performance of nanowires (NWs) has been a subject of intense research efforts due to gaining relevance in controlling functional... As an important component of nanodevices and nanomachine constructions, the mechanical performance of nanowires (NWs) has been a subject of intense research efforts due to gaining relevance in controlling functionality of nanoelectromechanical systems (NEMS); meanwhile, one of the characteristics of the NEMS is the dependence of the functionality of the systems upon the applied electric field. The study of the electric effects on the Young's modulus of nanostructures is of certain usefulness in the design of NEMS and the precise measurement of mechanical properties of one-dimensional nanostructures. This paper reviews the origin of the size-dependence of the elastic property of NWs and the factors influencing the discrepancies and inconsistencies in the measured values of the Young's modulus for the NW, besides the surface effects, nonlinear effects, the electromechanical coupling effects as a possible effect responsible for the differences in quantitative and qualitative performance of the measured Young's modulus for the NWs versus the diameter are clarified. 展开更多
关键词 NANOWIRES Young's modulus molecular dynamics simulations continuum mechanics theory electric effects
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Structural Synthesis of a Class of 2R2T Hybrid Mechanisms 被引量:5
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作者 TIAN Chunxu FANG Yuefa GUO Sheng 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2016年第4期703-709,共7页
Conventional overconstrained parallel manipulators have been widely studied both in industry and academia,however the structural synthesis of hybrid mechanisms with additional constraints is seldom studied,especially ... Conventional overconstrained parallel manipulators have been widely studied both in industry and academia,however the structural synthesis of hybrid mechanisms with additional constraints is seldom studied,especially for the four degrees of freedom(DOF) hybrid mechanisms.In order to develop a manipulator with additional constraints,a class of important spatial mechanisms with coupling chains(CCs) whose motion type is two rotations and two translations(2R2T) is presented.Based on screw theory,the combination of different types of limbs which are used to construct parallel mechanisms and coupling chains is proposed.The basic types of the general parallel mechanisms and geometric conditions of the kinematic chains are given using constraint synthesis method.Moreover,the 2R2T motion pattern hybrid mechanisms which are derived by adding coupling chains between different serial kinematic chains(SKCs) of the corresponding parallel mechanisms are presented.According to the constraint analysis of the mechanisms,the movement relationship of the moving platform and the kinematic chains is derived by disassembling the coupling chains.At last,fourteen novel hybrid mechanisms with two or three serial kinematic chains are presented.The proposed novel hybrid mechanisms and construction method enrich the family of the spatial mechanisms and provide an instruction to design more complex hybrid mechanisms. 展开更多
关键词 parallel mechanisms structural synthesis hybrid mechanisms screw theory
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Pyrolysis mechanism of glucose and mannose: The formation of 5-hydroxymethyl furfural and furfural 被引量:4
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作者 Bin Hu Qiang Lu +4 位作者 Xiaoyan Jiang Xiaochen Dong Minshu Cui Changqing Dong Yongping Yang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2018年第2期486-501,共16页
Fast pyrolysis of biomass will produce various furan derivatives, among which 5-hydroxymethyl furfural(5-HMF) and furfural(FF) are usually the two most important compounds derived from holocellulose. In this study... Fast pyrolysis of biomass will produce various furan derivatives, among which 5-hydroxymethyl furfural(5-HMF) and furfural(FF) are usually the two most important compounds derived from holocellulose. In this study, density functional theory(DFT) calculations are utilized to reveal the formation mechanisms and pathways of 5-HMF and FF from two hexose units of holocellulose, i.e., glucose and mannose. In addition, fast pyrolysis experiments of glucose and mannose are conducted to substantiate the computational results, and the orientation of 5-HMF and FF is determined by 13C-labeled glucoses. Experimental results indicate that C1 provides the aldehyde group in both 5-HMF and FF, and FF is mainly derived from C1 to C5 segment. According to the computational results, glucose and mannose have similar reaction pathways to form 5-HMF and FF with d-fructose(DF) and 3-deoxy-glucosone(3-DG) as the key intermediates. 5-HMF and FF are formed via competing pathways. The formation of 5-HMF is more competitive than that of FF, leading to higher yield of 5-HMF than FF from both hexoses. In addition, compared with glucose,mannose can form 5-HMF and FF via extra pathways because of the epimerization at C2 position. Therefore, mannose pyrolysis results in higher yields of 5-HMF and FF than glucose pyrolysis. 展开更多
关键词 Pyrolysis mechanism 5-HMF FF Density functional theory ^13C isotope labeling
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Structural and Mechanistic Studies of γ-Fe2O3 Nanoparticle as Capecitabine Drug Nanocarrier 被引量:2
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作者 ETEBARI Nasfin MORSALI Ali BEYRAMABADI S.Ali 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2018年第3期375-382,共8页
Using density functional theory,noncovalent interactions and four mechanisms of covalent functionalization of capecitabine anticancer drug onto γ-Fe2O3 nanoparticles have been investigated.Quantum molecular descripto... Using density functional theory,noncovalent interactions and four mechanisms of covalent functionalization of capecitabine anticancer drug onto γ-Fe2O3 nanoparticles have been investigated.Quantum molecular descriptors of noncovalent configurations were studied.It was specified that binding of capecitabine onto γ-Fe2O3 nanoparticles is thermodynamically suitable.Hardness and the gap of energy between LUMO and HOMO of capecitabine are higher than the noncovalent configurations,showing the reactivity of capecitabine increases in the presence of γ-Fe2O3 nanoparticles.Capecitabine can bond to γ-Fe2O3 nanoparticles through OH(k1 mechanism),NH(k2 mechanism),CO(k3 mechanism) and F(k4 mechanism) groups.The activation energies,activation enthalpies and activation Gibbs free energies of these reactions were calculated.It was specified that the k1 and k2 mechanisms are under thermodynamic control and k3 and k4 under kinetic control.These results could be generalized to other similar drugs. 展开更多
关键词 γ-Fe2O3 nanoparticles capecitabine density functional theory noncovalent and covalent functionalization mechanism
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Modeling multiband emissions from two young SNRs with a time-dependent magnetic field 被引量:1
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作者 Yun-Yong Tang Zu-Cheng Dai Li Zhang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2013年第5期537-546,共10页
The nonthermal components in hard X-rays have been detected in two young supernova remnants (SNRs): SN 1006 and Kepler's SNR. Various theoretical models showed that the amplification of the magnetic field was cruc... The nonthermal components in hard X-rays have been detected in two young supernova remnants (SNRs): SN 1006 and Kepler's SNR. Various theoretical models showed that the amplification of the magnetic field was crucial to explain their multiband emission properties. We investigate the evolution of the magnetic field and model the multiband emissions from these two young SNRs with a time-dependent injection model. The results indicate that (1) the radio and X-ray emissions are re- produced by synchrotron radiation of the injected electrons, while the y-rays can be explained as inverse Compton scattering of the relativistic electrons and proton-proton interaction of the high-energy protons; and (2) the amplification of the magnetic field spontaneously happens with reasonable parameters. 展开更多
关键词 Key words: radiation mechanisms: non-thermal -- gamma-rays: theory -- (ISM:)supernova remnant
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Effects of generally anisotropic crustal rocks on fault-induced displacement and strain fields
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作者 E.Pan W.A.Griffith H.Liu 《Geodesy and Geodynamics》 2019年第5期394-401,共8页
We present a new solution for the elastic displacement and strain fields on or near Earth’s surface due to rectangular faults in an anisotropic half-space,expressed as a summation of(A)the solution in an infinite spa... We present a new solution for the elastic displacement and strain fields on or near Earth’s surface due to rectangular faults in an anisotropic half-space,expressed as a summation of(A)the solution in an infinite space which is singular,and(B)the complementary part which is regular and well-behaved.These two solutions are expressed in terms of the mathematically elegant and computationally powerful Stroh formalism and can be applied to the generally anisotropic rock half-space or a transversely isotropic rock mass with any oriented plane of isotropy.For any flat fault of polygonal shape,one needs only to carry out a simple line integral from 0 to 7 r in order to express the fault-induced response.Numerical examples are presented to demonstrate the significant effect of the rock anisotropy and layer orientation on the fault-induced displacement and strain fields in anisotropic rocks.Potential applications are wide ranging,from faults in sedimentary strata to strongly deformed metamorphic rocks with steeply dipping foliation. 展开更多
关键词 GEOmechanics Rock ANISOTROPY BEDDING plane Deformation and strain FIELDS mechanics theory and modelling
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Investigation for Electromechanical Coupling Unstability of Rolling Mill
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作者 TANG Hua-ping 1, WANG Dong-yun 2, ZHONG Jue 1 (1. College of Mechanical and Electrical Engineering, Central South University, Changsha 410083, China 2. Zhong Yun Technology Institute, Zhengzhou 450007, China) 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第S1期68-,共1页
The unsteady condition of rolling Mill vibration that was caused by flexural vibration of strip was investigated. The parametric flexural vibration equation of rolled strip was established. The parametric flexural vib... The unsteady condition of rolling Mill vibration that was caused by flexural vibration of strip was investigated. The parametric flexural vibration equation of rolled strip was established. The parametric flexural vibration stability of rolled strip was studied and region of stability and unstability was determined based on Floquet theory and perturbation method. The flexural-vibration of strip was unstable if the frequency of variable tension was twice as the natural frequency of flexural-vibration strip. The characteristics of electric current in a temp driving motor’s main loop was studied and tested, and approved that there were 6 humorous current ponderance and 12 humorous current ponderance in main circuit of driving motor. Vertical vibration of working roller was tested, the test approved that there were running unsteady caused by parametric vibration. It attached importance to the parametric vibration of rolling mill. 展开更多
关键词 rolling mill parametric vibration floquet theory and mechanism
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Can the bump in the composite spectrum of GRB 910503 be an emission line feature of gamma-ray bursts?
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作者 Yi-Ping Qin Fu-Wen Zhang 《Chinese Journal of Astronomy and Astrophysics》 CSCD 2005年第6期627-635,共9页
Appearing in the composite spectral data of BATSE, EGRET and COMPTEL for GRB 910503, there is a bump at around 1600keV. We perform a statistical analysis on the spectral data, trying to find out if the bump could be a... Appearing in the composite spectral data of BATSE, EGRET and COMPTEL for GRB 910503, there is a bump at around 1600keV. We perform a statistical analysis on the spectral data, trying to find out if the bump could be accounted for by a blue-shifted and significantly broadened rest frame line due to the Doppler effect of an expanding fireball surface. We made an F-test and adopted previously proposed criteria. The study reveals that the criteria are well satisfied and the feature can be interpreted as the blue shifted 6.4 keV line. From the fit with this line taken into account, we find the Lorentz factor of this source to be F = 116-9^+9 (at the 68% confident level, △X^2 = 1) and the rest frame spectral peak energy to be E0,p=2.96-0.18^+0.24 ke V.Although the existence of the emission line feature requires other independent tests to confirm, the analysis suggests that it is feasible to detect emission line features in the high energy range of GRB spectra when taking into account the Doppler effect of fireball expansion. 展开更多
关键词 GAMMA-RAYS bursts - gamma-rays theory - radiation mechanisms nonthermal - relativity
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A New Approach for Estimating Kinetic Luminosity of Jet in AGNs
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作者 Mao-Li Ma Xin-Wu Cao Dong-Rong Jiang Min-Feng Gu 《Chinese Journal of Astronomy and Astrophysics》 CSCD 2008年第1期39-49,共11页
The Konigl inhomogeneous jet model can successfully reproduce most observational features of jets in active galactic nuclei (AGN), when suitable physical parameters are adopted. We improve Konigl's calculations on ... The Konigl inhomogeneous jet model can successfully reproduce most observational features of jets in active galactic nuclei (AGN), when suitable physical parameters are adopted. We improve Konigl's calculations on the core emission from the jet with a small viewing angle θ0 - φ (φ is half opening angle of the conical jet). The proper motion of the jet component provides a constraint on the jet kinematics. Based on the inhomogeneous jet model, we use the proper motion data of the jet component to calculate the minimal kinetic luminosity of the jet required to reproduce the core emission measured by the very-long- baseline interferometry (VLBI) for a sample of BL Lac objects. Our results show that the minimal kinetic luminosity is slightly higher than the bolometric luminosity for most sources in the sample, which implies that radiatively inefficient accretion flows (RIAFs) may be in those BL Lac objects, or/and the properties of their broad-line regions (BLRs) are significantly different from flat-spectrum radio-loud quasars. 展开更多
关键词 GALAXIES jet -kinematics and dynamics theory - radiation mechanisms nonthermal-BL Lac objects general
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New upper limit on the cosmological constant from solar system dynamics
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作者 Shuang Liang Yi Xie 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2014年第5期527-532,共6页
The cosmological constant A is the simplest model for explaining the dark energy which supposedly drives the observed accelerated expansion rate of the Universe. Together with the concept of cold dark matter, it satis... The cosmological constant A is the simplest model for explaining the dark energy which supposedly drives the observed accelerated expansion rate of the Universe. Together with the concept of cold dark matter, it satisfactorily accommo- dates a wealth of observations related to cosmology. Due to its assumed constancy throughout the Universe, A might also affect the dynamics of the planets in the so- lar system, although with extremely small effects. However, modern high-precision ephemerides provide a promising tool for constraining it. Using the supplementary advances in the perihelia provided by current INPOP10a and EPM2011 ephemerides, we obtain a new upper limit on A in the solar system when the Lense-Thirring ef- fect due to the Sun's angular momentum and the uncertainty of the Sun's quadrupole moment are properly taken into account. These two factors were mostly absent in pre- vious works dealing with A. We find that INPOP10a yields an upper limit of A = (0.26±1.45) × 10^-43 m^-2 and EPM2011 gives A = (-0.44 4±8.93) × 10^-43 m^-2. Such bounds are about 10 times less than previously estimated results. 展开更多
关键词 COSMOLOGY theory -- celestial mechanics -- ephemerides -- relativity
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Degenerative myopia: mechanical theories revisited
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作者 F.Javier Carreras 《Annals of Eye Science》 2018年第1期132-135,共4页
The article discusses the early abandonment of mechanical theories about eye enlargement in degenerative myopia at the turn of the 20th century.At that time,the number of theories about myopia grew unrestricted,but wi... The article discusses the early abandonment of mechanical theories about eye enlargement in degenerative myopia at the turn of the 20th century.At that time,the number of theories about myopia grew unrestricted,but with scant support from the experimental field.The mechanical theories vanished as a new wave of metabolism-based theories appeared,propelled by the huge advances in molecular biology.Modern techniques allow reconsidering those theories and to put them to test with higher confidence. 展开更多
关键词 Degenerative myopia mechanical theories extra and intraocular muscles botulinum toxin(BT)
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THEORETICAL ANALYSIS OF HYDROGENATION MECHANISM CATALYZED BY Pd-Fe_2O_3/D_(3520)
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作者 胡卫兵 张胜民 张曼征 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 1996年第4期35-38,共4页
The mechanism of catalytic hydrogenation of styrene is analyzed by catalysis theory and frontier molecular orbital theory.
关键词 olefinic double bonds hydrogenation mechanism frontier molecular orbital theory
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A synchrotron self-Compton scenario for the very high energy γ-ray emission of the intermediate BL Lacertae object W Comae
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作者 Jin Zhang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2009年第7期777-782,共6页
W Comae has significant variability in multi-wavelengthes, from radio to gamma-ray bands. A bright outburst in optical and X-ray bands was observed in 1998, and most recently, a strong TeV flare was detected by VERITA... W Comae has significant variability in multi-wavelengthes, from radio to gamma-ray bands. A bright outburst in optical and X-ray bands was observed in 1998, and most recently, a strong TeV flare was detected by VERITAS in 2008. It is the first TeV intermediate-frequency-peaked BL Lacertae source. I find that both the broadband spectral energy distributions (SEDs) which were quasi-simultaneously obtained during the TeV flare and during the optical/X-ray outburst are well fit by using a single-zone synchrotron + synchrotron-self-Compton model. The satisfactory fitting requires a large beaming factor, i.e., δ- 25 and δ- 20 for the TeV flare and the optical/X-ray outburst, respectively, suggesting that both the optical/X-ray outburst and the TeV flare are from a relativistic jet. The size of the emission region of the TeV flare is three times larger than that of the optical/X-ray outburst, and the strength of the magnetic field for the TeV flare is - 14 times smaller than that of the X-ray/optical outburst, likely indicating that the region of the TeV flare is more distant from the core than that of the X-ray/optical outburst. The inverse Compton component of the TeV flare peaks around 1.3 GeV, but it is around 20 MeV for the X-ray/optical outburst, lower than that for the TeV flare by two orders of magnitude. The model predicts that the optical/X-ray outburst might be accompanied by a strong MeV/GeV emission, but the TeV flare may be not associated with the X-ray/optical outburst. The GeV emission is critical for characterizing the SEDs of the optical/X-ray outburst and the TeV flare. The predicted GeV flux is above the sensitivity of Fermi/LAT, and it could be verified with the observations by Fermi/LAT in the near future. 展开更多
关键词 BL Lacertae objects: individual: W Comae - gamma-rays observations - gamma-rays theory - radiation mechanisms non-thermal
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The transmission mechanism theory of disease dynamics:Its aims,assumptions and limitations
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作者 Winston Garira Bothwell Maregere 《Infectious Disease Modelling》 CSCD 2023年第1期122-144,共23页
Most of the progress in the development of single scale mathematical and computational models for the study of infectious disease dynamics which now span over a century is build on a body of knowledge that has been de... Most of the progress in the development of single scale mathematical and computational models for the study of infectious disease dynamics which now span over a century is build on a body of knowledge that has been developed to address particular single scale descriptions of infectious disease dynamics based on understanding disease transmission process.Although this single scale understanding of infectious disease dynamics is now founded on a body of knowledge with a long history,dating back to over a century now,that knowledge has not yet been formalized into a scientific theory.In this article,we formalize this accumulated body of knowledge into a scientific theory called the transmission mechanism theory of disease dynamics which states that at every scale of organization of an infectious disease system,disease dynamics is determined by transmission as the main dynamic disease process.Therefore,the transmission mechanism theory of disease dynamics can be seen as formalizing knowledge that has been inherent in the study of infectious disease dynamics using single scale mathematical and computational models for over a century now.The objective of this article is to summarize this existing knowledge about single scale modelling of infectious dynamics by means of a scientific theory called the transmission mechanism theory of disease dynamics and highlight its aims,assumptions and limitations. 展开更多
关键词 Single scale modelling of infectious disease dynamics Multiscale modelling of infectious disease dynamics Scales of organization of infectious disease system Transmission mechanism theory of disease dynamics Levels of organization of infectious disease system The replication-transmission relativity theory of disease dynamics
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Multi-wavelength emission from 3C 66A: clues to its redshift and gamma-ray emission location
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作者 Da-Hai Yan Zhong-Hui Fan +1 位作者 Yao Zhou Ben-Zhong Dai 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2013年第4期411-419,共9页
The quasi-simultaneous multi-wavelength emission of TeV blazar 3C 66A is studied by using a one-zone multi-component leptonic jet model. It is found that the quasi-simultaneous spectral energy distribution of 3C 66A c... The quasi-simultaneous multi-wavelength emission of TeV blazar 3C 66A is studied by using a one-zone multi-component leptonic jet model. It is found that the quasi-simultaneous spectral energy distribution of 3C 66A can be well reproduced; in particular, the first three months of its average Fermi-LAT spectrum can be well reproduced by the synchrotron self-Compton component plus external Compton component of the broad line region (BLR). Clues to its redshift and gamma-ray emission location are obtained. The results indicate the following. (i) On the redshift: The theoretical intrinsic TeV spectra can be predicted by extrapolating the reproduced GeV spectra. Through comparing these extrapolated TeV spectra with the corrected observed TeV spectra from extragalactic background light, it is suggested that the redshift of 3C 66A could be between 0.1 and 0.3, with the most likely value being ~ 0.2. (ii) On the gamma-ray emission location: To well reproduce the GeV emission of 3C 66A under different assumptions on the BLR, the gamma-ray emission region is always required to be beyond the inner zone of the BLR. The BLR absorption effect on gamma-ray emission confirms this point. 展开更多
关键词 BL Lacertae objects: individual (3C 66A) - galaxies: active - gamma-rays: theory - radiation mechanisms: non-thermal
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