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比较了在牛顿力学和广义相对论框架中有效势的特征,对比了广义相对效势和两种伪牛顿有效势(PW有效势力和LC有效势)所对应的最内稳定圆轨道半径和放能效率,结果表明,PW有效势能很好地描述检验粒子在Schwarzschild黑洞赤道面上的轨道特征,LC有效势也能较好地模拟检验粒子在Kerr黑洞赤道面上的轨道特征(顺行粒子向快转黑洞吸积的情况除外)。  相似文献   
2.
提出了一种磁场提取黑洞吸积盘能量的解析模型,其中涉及到3种能量机制: (1) Blandford-Znajek (BZ)与连接黑洞与天体物理负载的开放磁力线有关, (2) 磁耦合(MC)过程与连接黑洞与盘负载的闭合磁力线有关, (3) DL过程与连接吸积盘与天体物理负载的开放磁力线有关.利用等效电路导出上述能量机制的电磁功率和力矩表达式.此外还讨论了这个模型潜在的天体物理应用.  相似文献   
3.
阐述了一种包括三种放能机制在内的磁化黑洞吸积盘的统一模型,在广义相对论框架中导出满足Max-well方程的磁耦合映射关系,在黑洞基本演化方程的基础上得出描述黑洞演化状态的特征函数,分析了黑洞自转参量演化的平衡点及特征,讨论了统一模型的各参量对磁化黑洞吸积盘放能效率的影响,计算表明,在黑洞视界面磁压满足冲压平衡条件下,黑洞吸积盘的最大放能效率可达44.5%。  相似文献   
4.
研究了钛酸钾晶须对热硫化硅橡胶复合材料的硫化特性、力学性能及热稳定性的影响,通过扫描电镜观察了复合材料的断面及晶须在基体中的分散性。结果表明:钛酸钾晶须能促进硅橡胶的硫化,提高其最高扭矩;同时,钛酸钾晶须对硅橡胶具有一定的补强作用,拉伸强度、硬度等随晶须用量的增加而增大;钛酸钾晶须的引入,使硅橡胶复合材料的热稳定性明显提高,填充量为9vol%时,与纯硅橡胶相比,复合材料的热分解温度提高了65℃,Kissinger法求出填充量为12vol%的钛酸钾晶须/硅橡胶复合材料的热分解活化能为193.62kJ/mol,高于相同填充量的白炭黑/硅橡胶复合材料,具有较好的热稳定性。  相似文献   
5.
An analytical model of black hole(BH) evolution is proposed by considering the Blandford-Znajek process with a tansient magnetized accretion disc,which is used as a central engine for powering gamma ray bursts(GRBs),The state of BH evolution can be described by the representative points in the corresponding sub-regions of a parameter space.It is shown that the BH spin might be spun up rather than slowed down.provided that the ratio of the angular velocity of the magnetic field lines to that of the BH horizon is greater than a critical value.In addition,the effects of some initial values of the BH system on the evolution terminals and the output energy for GRBs are discussed in the parameter space.  相似文献   
6.
We propose a model of the magnetic coupling (MC) of a retating black hole(BH) with the surrounding accretion disc in order to study the radial temperature profile in the inner region of the disc,in which a linear map from the angular coordinate on the BH horizon to the radial coordinate on the thin disc is given by closed magnetic field lines.The MC power and torque are derived using a modified equivalent circuit.It is shown that the MC effects on the temperature profile are related intimately to the BH spin,resulting in the variation of the value and the position of the peak temperature.It turns out that the value range of the colour temperature of the disc is extended by the MC effects.  相似文献   
7.
Evolution characteristics of a rotating black hole (BH) are discussed in coexistence of the Blandford-Znajek (BZ) process and the magnetic coupling (MC) process in the parameter space consisting of the BH spin and the power-law index of the magnetic field on the disc. The condition for the coexistence of the two energy mechanisms are derived by using the mapping relation between the angular coordinate on the BH horizon and the radial coordinate on the disc. It is shown that not only the two mechanisms can coexist, but also the power and the rate of change of BH entropy in the BZ process will dominate over those in the MC process, provided that the BH spin and the power-law index are great enough.  相似文献   
8.
We discuss the feature of the magnetic field configuration arising from double counter oriented electric currentrings in the accretion disc around a Kerr black hole (BH). We discuss the relevant physical quantities corresponding to this configuration: (1) the power and torque transferred by the large-scale magnetic field, (2) the angular momentum and energy fluxes transferred from the BIt to the inner disc, (3) the radiation flux from the disc. In addition, we discuss the possibility that the closed magnetic field anchored at the disc probably evolves to the open magnetic field, which is helpful to produce the jet from the disc.  相似文献   
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