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31.
磁埃里克森制冷循环的回热性能 总被引:3,自引:0,他引:3
严子浚 《厦门大学学报(自然科学版)》1995,34(3):348-352
从普遍的铁磁体物态方程出发,讨论了磁埃里克森制冷循环的回热性能.井指出有关文献中用△Q_(in)=0作为循环可实现理想回热的条件是错误的. 相似文献
32.
任传福 《系统工程与电子技术》1991,(2)
本文叙述了主要用于国防各种型号武器中的集中参数环行器,从理论上分析了环行器的工作原理,并给出计算公式和设计曲线。为适应宽的工作温度范围需要,本文对环行器的温度补偿技术进行了分析,采用新型的Ni30Cr10热磁合金片构成具有温度补偿的闭合磁路,已研制成功了温度范围为-40~+55℃的集中参数环行器/隔离器。这种器件除用于遥测弹上外还广泛用于各种雷达系统和通讯设备中。 相似文献
33.
S. Benvenuti A. Gagliardo T. Guilford P. Luschi 《Cellular and molecular life sciences : CMLS》1996,52(6):608-612
In order to investigate the pigeon's compass mechanism, a series of overcast tests with clock-shifted birds were run at two familiar release sites. While controls were able to assume a correct homeward direction, the experimental birds' initial orientation cannot be explained either on the basis of a time-compensated sun compass or of a time-independent magnetic compass. Speculative explanations of our paradoxical results are attempted. 相似文献
34.
徐慧 《中南大学学报(自然科学版)》1986,(5)
本文在强耦合极限下,讨论了一维扩展Hubbard模型的磁化率性质,并得到铁磁性、反铁磁性和顺磁性在此模型中都可能出现的结论。特别是在磁化率的表达式中出现了相当于有两种点阵存在时的交换积分J_1和J_2,而此模型只考虑了一种点阵。 相似文献
35.
施传柱 《曲靖师范学院学报》2001,20(6):37-39,51
以静磁场的基本方程为基础,利用矢量分析的有关知识对磁场强度H的一般形式作一些理论分析,给出磁场强度日仅与传导电流有关的条件. 相似文献
36.
郑俊博 《西安联合大学学报》2000,3(2):58-61
用普通物理学的方法推导了不同惯性系之间产场量的变换式,在此基础上,给出了一咱简便、快捷并且物理意义清晰的建立麦克斯韦方程组的新途径。 相似文献
37.
In the process of ferromagnetic thermoseeds mediated magnetic induction hyperthermia, the tempera- ture distribution in the tumor region is a key factor to determine the therapy effect. During the preoperative treatment planning, discrepancies of the treatment parameters may lead to the temperature distribution uncertainty within the target area. Inaccurate prediction of temperature distribution may induce the treatment failure; therefore, it would be significant to investigate the uncertainty of tissue temperature prediction caused by the disturbance of calculation parameters. In this paper, 3D temperature field and necrosis zone of tissues in ferromagnetic thermoseeds hyperthermia are simulated by the finite volume algorithm, and effects of parameter uncertainties on the temperature distribution are revealed. Results show that selecting appropriate magnetic field parameters for treatment is a priority to guarantee therapeutic effect. Thermoseed properties and blood perfusion rate are the obvious disturbing terms for temperature distribution, while the metabolic heat of bio-tissues can often be ignored within limits. Our investigation is of importance for guiding reasonable and optimal preoperative treatment planning. 相似文献
38.
39.
Chao Jing Liju Yu Dong Zheng Pan Liao Yiming Cao Jianhui Liang Zhe Li Baojuan Kang Jincang Zhang 《自然科学进展(英文版)》2015,25(2):117-121
Thin film of Ni50Mn35In15 Heusler alloy was prepared on Mg O(001) substrate by epitaxial growth in an ultra-high vacuum(UHV) chamber by a Pulsed Laser Deposition(PLD) method. The epitaxial growth process was monitored by in situ reflection high energy electron diffraction(RHEED) and the structure of the film was checked by ex situ X-ray diffraction(XRD), which indicates that high quality Ni50Mn35In15 single crystal film with a face-centered-cubic(fcc) structure could be stabilized on Mg O(001). Magnetic property measurement was also conducted at various temperatures by using physical property measurement system(PPMS). A significant exchange bias was observed for Ni50Mn35In15 film,and the strength of the exchange bias field(HEB) increases with the decrease of temperature. Such a behavior can be ascribed to the fact that the interfacial spin interaction between ferromagnetic(FM) and antiferromagnetic(AFM) cluster is enhanced with the decrease of temperature. 相似文献
40.
Magnetoelectric Bi3.15Nd0.85Ti3O12–NiFe2O4(BNT–NFO) bilayer films were deposited on Pt/Ti/SiO2/Si(100) substrates by a simple SOL–GEL method and spin-coating process with different growth sequences of BNT and NFO yielding the following layered structures: BNT/NFO/substrate(BNS) and NFO/BNT/substrate(NBS). Such heterostructures present simultaneously strong ferroelectric and ferromagnetic responses,as well as magnetoelectric effects at room temperature. BNS thinfilms showed larger ME voltage coefficient than NBS films, revealing that the layer sequences have a significant in fluence on the magnetoelectric coupling behavior of these bilayer structures, which may be caused by a interfacial effect. 相似文献