磁带及其磁带程序转换和复制

本文简要叙述磁带的技术指标和磁带机的工作过程,给出了一个磁带程序的转换程序,最后介绍UNIX╱XENIX系统格式和非UNIX╱XENIX系统格式之间的文件转换实用程序dd命令及其应用。     

矿用隔爆兼本质安全交流变频调速装置在云冈矿主斜井皮带的应用

根据在生产过程中遇到的问题,设计改造了矿用隔爆兼本质安全交流变频调速装置,本装置加上可编程控制器（PLC）、显示器等构成了一部操作简单、功能强大、工作可靠的机电一体化产品。     

Heating effect and biocompati bility of bacteri al magnetoso mes as potential materials used in magnetic fluid hyperthermia

Magnetic fluid hyperthermia (MFH) promises to be a viable alternative in the treatment of localized cancerous tumors.The treatment consists of introducing nanoparticles as energy absorbent agents in tu...     

Solvother mal synthesis of Co1-xNixFe2O4 nanoparticles and its application in ammonia vapors detection

Magnetic Co1-xNixFe2O4 nanoparticles (NPs) were successfully synthesized via a solvothermal method using ethylene glycol as solvent.The samples were characterized by X-ray diffraction (XRD),field emiss...     

核磁共振成像原位监测冰融化及四氢呋喃水合物分解的微观过程

核磁共振成像(Magnetic Resonance Imaging,MRI)可以通过物质在不同相态之间的亮度差别来识别物质相态的变化,冰、水和水合物之间较大的亮度对比使MRI成为监测水合物生成分解动态过程的有效工具.采用MRI原位监测了冰融化和四氢呋喃(THF)水合物分解的微观过程,从微观角度对比研究了THF水合物分解与冰融化过程的异同.冰融化和THF水合物的分解过程受传热程控,冰的融化和水合物的分解总是沿着固-液界面从外向内推进,消解速度持续加快.固相表面的"结构化水层"是冰和水合物立体结构瓦解的主要原因.THF水合物的分解过程与气体水合物不同,没有明显的"自保护效应".由于温度梯度产生的密度差异,液相产生自然对流,造成了水合物的分解及冰的融化过程中固-液界面运动的随机性.     

铁磁材料的磁路图解法计算

用试探法计算无分支不均匀恒定磁通磁路的反面问题的计算相当繁琐。本文推导找出一种快捷准确求磁通的方法——图解法。     

电子荷质比测量实验的Matlab仿真

运用Matlab实现了对电子荷质比e/m测量过程的仿真,着重对电子在磁场中的运动轨迹以及磁聚焦现象进行可视化仿真,从而可用于提高本实验项目的教学效果。     

北斗RTK的定位实验与精度分析

通过实际测试,将北斗RTK和GPSRTK进行对比,了解北斗RTK的实际定位精度情况。测试结果表明,GPSRTK和北斗RTK定位的平面点位中误差分别为37.3mm和41.7mm,证明北斗系统和GPS的平面定位精度基本在同一量级上,能够满足RTK测量的需要。     

Magnetic characteristics and its environmental implications of core YSJD-86GC sediments from the southern South China Sea

Sediments of core YSJD-86GC （referred to as 86GC） collected from the southern South China Sea were selected for environmental magnetic studies. Combined with the published chronological framework, sediment magnetic properties were revealed for the study area since the MIS3 stage. The rock magnetic results indicate that low-coercivity magnetite is the main magnetic mineral within the sediments. Also, a certain amounts of hematite are present. The King plot and Day plot, which reflect the magnetic particle size, show that fine-grained pseudo-sin- gle-domain phase magnetic particles dominate the magnetic minerals in the sediments. Comparison of magnetic parameters and geochemical indicators show that magnetic properties of core 86GC sediments reflect a terrigenous input. Simultaneously, magnetic characteristics of the stud- ied sediment are influenced by the quantity of terrigenous sediment input, oxidation-reduction conditions of the provenance area, and the transportation environment and distance. Sea level fluctuation caused by global climate change was the main factor for variation in concentration of magnetic minerals and magnetic particle size of thestudied core sediments. Thus, variation of sediment magnetic properties in the study area can be used as an indirect indicator of sea level fluctuation.     

Observation of directional change of core field inside flux ropes within one reconnection diffusion region in the Earth’s magnetotail

Two consecutive magnetic flux ropes, separated by less than 30 s （△t 〈 30 s）, are observed within one magnetic reconnection diffusion region without strong guide field in the Earth＇s magnetotail by Cluster multispacecraft. The flux ropes are characterized by bipolar signatures of the south-north magnetic field component Bz accompanied with strong core magnetic field By, intense current J and density depletions inside of them. In spite of the small but non-trivial global scale negative guide field （-By）, there exists a directional change of the core fields of two flux ropes, i.e., -By for the first one, and ＋By for the second one. The directions of the core fields are the same as the ambient cross-tail magnetic field component （By） just outside of flux ropes. Therefore, we suggest that the core field of flux ropes is formed by compression of the local preexisting By and that the directional change of core field is due to the change of local preexisting By. Such a change in ambient By might be caused by some microscale physics.