Magnetic Physical Properties Research Articles

Graphene Encapsulated Low-Load Nitrogen-Doped Bimetallic Magnetic Pd/Fe@N/C Catalyst for the Reductive Amination of Nitroarene Under Mild Conditions.

The online version contains supplementary material available at 10.1007/s10562-023-04273-7.

Thermal Explosion in a 2Co–Ti–Al System: Combustion, Phase Formation, and Properties

Combustion and the formation of structures and phases in a 2Co–Ti–Al system during self-propagating high-temperature synthesis in a thermal explosion are under study. It is determined that a single-phase product (a Co2TiAl Geissler compound) can be obtained in this system. Morphology, microstructure, and physical-magnetic properties of combustion products of the system are investigated.

Influence of the Exchange-Correlation Functional on the Energy of Formation and Magnetic Behavior of Binary D03 Intermetallic Compounds FeM3 (M = Ti, Zr, Hf)

In recent years, ab-initio calculations based on the density functional theory became a commonly used tool in supporting, improving or even refuting experimental results in different research fields. In this work we discuss some accuracy aspects inherent to ab-initio electronic structure calculations regarding the understanding of different structural, electronic and magnetic physical properties. In particular, we discuss the dependence of the magnetic ground-state and the formation energy with the exchange-correlation functional for the binary intermetallic compounds FeTi3, FeZr3 and FeHf3 with D03 crystal structure. All exchange-correlation schemes used were based on the generalized gradient approximation. It is the aim of the present paper to call the attention of the community to some fundamental aspects of the calculations that can influence the final results and the conclusions derives from it.

Solar flare forecasting model with active region photospheric magnetic field properties and sunspot factors

Solar active region photospheric magnetic physical properties and sunspots factors are connected to research on solar flare short term forecasting. The significance of integrated parameters is discussed. Sunspots parameters are area, magnetic classification, Macintosh classification; and the magnetic physical properties are parameterized with the maximum horizontal gradient, the length of neutral line with the strong gradients, the number of singular points. Using flare productivity fitting function, the initial data set of predictors is normalized to form the modeling data set. Based on this data set, multi-layer perceptron is applied to building flare forecasting model. In experiment, the integrated forecasting model is compared with other two models which take sunspots and magnetic parameters separately. The results indicate that the integrated model has a higher accuracy rate and a lower false alarm rate.

Application of Solar Photospheric Magnetic Field Properties in SPE Short-term Forecast

利用SOHO/MDI全日面纵向磁图, 计算了三个描述太阳活动区磁场复杂性和非势性的特征物理量, 即纵向磁场最大水平梯度Bz, 强梯度中性线长度L, 孤立奇点数目η. 为检验太阳光球磁场特征在质子事件短期预报中是否有效, 采用BP神经网络方法, 建立了基于这三个磁场特征物理量简单的太阳质子事件短期(24h)预报模型. 模 型在对2002年和2003年连续两年的样本检测中, 有很高的准确率(2002年和2003年 分别为90 %, 87.54 %)和较高的 质子事件报准率(2002年和2003年分别为60 %, 75 %),从而为光球磁场特征物理量作为质子事件预报的有效因子提供了依据.