Search

TiO2-based magnetic semiconductors with high Co doping concentrations (Ti1-xCoxO2) were synthesized under thermal nonequilibrium condition by sputtering machine. Microstructure and composition analysis by transmission electron microscopy, x-ray photoelectron spectroscopy, and electron energy-loss spectroscopy indicated that Co element was incorporated into TiO2 to form Ti1-xCoxO2 compound. The direct evidence for the compositional inhomogeneity of the Ti1-xCoxO2 compound was given. Room temperature ferromagnetism with high magnetization was obtained, which could be attributed to the intrinsic properties of the amorphous magnetic semiconductor. The electrical transport in a low temperature range was explained by spin-dependent Efros’s variable range hopping, and correspondingly an exponential function of the magnetoresistance versus T-1/2 was found. [ABSTRACT FROM AUTHOR]

Coronal mass ejection (CME) is the large scale magnetized plasmoid ejected from the Sun, which brings huge amount of magnetic flux and plasma into interplanetary space. An earthward CME will interact with the magnetosphere of the Earth, and invokes the substorm and the other phenomena of the space weather as it approaches to the Earth. The 2-dimensional data provided by the current observational techniques cannot describe the true magnetic structure and the plasma distribution of CMEs comprehensively. We need to look into the 3-dimensional structure and the associated three components of CME speeds in order to predict the time when an ICME (Interplanetary CME) reaches the Earth, and the potential consequent impact on the Earth and the nearby environment. In this paper, 3D reconstruction methods of CME based on existing imaging observations are introduced, including two kinds of reconstruction methods based on coronagraph data and heliosphere imager data, and CME-driven shock wave 3D reconstruction methods with high correlation with CME imaging reconstruction. Each method shows apparent advantages in dealing with specific events, but its weakness and necessary constrains to its applications exist as well. Results obtained via various methods are compared in this work, and we found that CME velocities and moving directions deduced from these methods are fairly close to one another, which shows high reliability of these methods. Finally, the hot topics related to the 3-dimensional reconstruction of CME (ICME) and the relevant development in reconstructing methods are also discussed. [ABSTRACT FROM AUTHOR]

This paper is to introduce a proposed deep space mission, which aims to perform in situ detection of the central structure, namely the magnetic reconnection current sheet, which drives the large-scale eruption on a star. The main focus of this mission is on the fine physical characteristics of the large-scale magnetic reconnection taking place on the Sun, our nearest star, revealing the secret of the most violent energy release process, also known as the solar storm, in the solar system. The scientific goal of this mission, magnetic reconnection, is a kernel process of energy conversion occurring in the magnetized plasma in the universe, and has long been a fairly important research topic or even research area in solar physics, space science, plasma physics, and the related fields. The in situ detection with a 5 ∼ 20 times enhanced spatial resolution of the instruments used on the Earth will provide us with the extra-clear images of the Sun and the related information. We are thus able to study, to learn, and to understand the Sun on an unprecedented platform, and further resolve the longstanding puzzle in the solar community regarding the fine physical property of the kernel process driving the solar eruption, as well as that of the coronal heating. [ABSTRACT FROM AUTHOR]