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111.
A heuristic derivation of an improved nonlinear guiding center theory for perpendicular diffusion of charged particles is presented. This new derivation complements previous work which is based on an indirect solution of the Fokker–Planck equation. The new derivation confirms the improved theory for diffusion of charged particles and makes the validity of the theory plausible.  相似文献   
112.
在飞机地面通常检查时,磁差给定器磁偏差值往往设定为当地磁差,才能得到正确的航向。校正磁罗差时,只有将磁差给定器设定为000.0,不然罗差计算会大大溢出指标。文章通过磁罗差校正的原理和校正方法的论述,进一步分析了校罗差时将磁偏给定器设定为000.0的工作机理。  相似文献   
113.
介绍了一种新型电工钢片磁性能无损检测传感器及其测量原理 ,同时讨论了该传感器的设计原则并给出了典型数据及仿真测试结果  相似文献   
114.
A current serious limitation on the studies of solar energetic particle (SEP) events is that their properties in the inner heliosphere are studied only through in situ spacecraft observations. Our understanding of spatial distributions and temporal variations of SEP events has come through statistical studies of many such events over several solar cycles. In contrast, flare SEPs in the solar corona can be imaged through their radiative and collisional interactions with solar fields and particles. We suggest that the heliospheric SEPs may also interact with heliospheric particles and fields to produce signatures which can be remotely observed and imaged. A challenge with any such candidate signature is to separate it from that of flare SEPs. The optimum case for imaging high-energy (E > 100 MeV) heliospheric protons may be the emission of π0-decay γ-rays following proton collisions with solar wind (SW) ions. In the case of E > 1 MeV electrons, gyrosynchrotron radio emission may be the most readily detectible remote signal. In both cases we may already have observed one or two such events. Another radiative signature from nonthermal particles may be resonant transition radiation, which has likely already been observed from solar flare electrons. We discuss energetic neutrons as another possible remote signature, but we rule out γ-ray line and 0.511 MeV positron annihilation emission as observable signatures of heliospheric energetic ions. We are already acquiring global signatures of large inner-heliospheric SW density features and of heliosheath interactions between the SW and interstellar neutral ions. By finding an appropriate observable signature of remote heliospheric SEPs, we could supplement the in situ observations with global maps of energetic SEP events to provide a comprehensive view of SEP events.  相似文献   
115.
116.
磁性液体,是由固体的磁性粒子分散到载体(液体)中形成的一种胶体溶液,此种深夜既有液体的流动性,又具有磁性,是一种新型的磁性材料,本文对磁性液体的制造方法,及其存在的条件,进行了研究与探讨,并简单介绍了磁性液体的性质及其应用前景。  相似文献   
117.
The spectral and polarization properties of thermal cyclotron radio emission from a hot coronal loop with a current along the axis are computed. The magnetic field is supposed to have a component along the loop axis as well as a poloidal part due to the current, both components being of comparable magnitude. In this specific configuration a helical magnetic field is present with a remarkable minimum of its absolute value along the loop axis and a maximum at its periphery. The presence of one or two maxima of magnetic field value along the line of sight results in increasing optical thickness of the gyroresonance layers at appropriate frequencies in the microwave band and, therefore, in enhanced radio emission at those harmonics which are optically thin (for example,s=4). These cannot be observed in models with the commonly employed magnetic field configuration (longitudinal along the loop axis).We show that the frequency spectrum of thermal cyclotron radiation from a hot coronal loop with a helical magnetic field differs from that of the standards-component source (with smooth frequency characteristics and polarization corresponding toe-mode) in that plenty of fine structures (line-like features and cut-offs) are present and theo-mode is prevalent in some frequency intervals. The enhanced radio emission at high harmonics and the complicated form of frequency spectrum in the model considered imply that some microwave sources, which are poorly explained in traditional models of solar active regions, may be associated with helical magnetic fields in hot coronal loops. Computations allow one to indicate spectral and polarizational peculiarities of local sources testifying to the presence of a helical magnetic field.  相似文献   
118.
Prominence seismology is a rapidly developing topic which seeks to infer the internal structure and properties of solar prominences from the study of its oscillations. An extensive observational background about oscillations in quiescent solar prominences has been gathered during the last 70 years. These observations point out the existence of two different types of oscillations: Flare-induced oscillations (winking filaments) which affect the whole prominence and are of large amplitude and small amplitude oscillations which seem to be of local nature. From the theoretical point of view, few models have been set up to explain the phenomenon of winking filaments while, on the contrary, for small amplitude oscillations a large number of models trying to explain the observed features have been proposed.  相似文献   
119.
推导出扇面波导中激励探针的等效输入电阻表达式,探针是伸入波导中的同轴线的内导体,在X波段,计算了输入电阻值随着探针伸入波导中不同长度的变化。  相似文献   
120.
Interplanetary coronal mass ejections (ICMEs) originating from closed field regions on the Sun are the most energetic phenomenon in the heliosphere. They cause intense geomagnetic storms and drive fast mode shocks that accelerate charged particles. ICMEs are the interplanetary manifestations of CMEs typically remote-sensed by coronagraphs. This paper summarizes the observational properties of ICMEs with reference to the ordinary solar wind and the progenitor CMEs.  相似文献   
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