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1.
测量了非晶态Fe_(90-x)Co_xZr_(10)和Fe_(90-y)Cr_yZr_(10)合金的热膨胀曲线和磁性,给出了自发体积磁致伸缩ω_s和平均原子磁矩μ与有效电子数n_(eff)的关系,实验结果表明,ω_s的峰值位置与μ开始急剧下降的位置(n_(eff)≈8.1~8.2)相对应,从而在非晶态金属——金属型团瓦合金中证实了因瓦效应与铁磁性的不稳定有关。  相似文献   

2.
本文研究了非晶态Fe_(79)B_(16)Si_5合金的退火脆化行为,分析了此合金的脆化规律;通过脆化温度、晶化温度、脆化与晶化激活能的测定,探讨了Fe_(79)B_(16)Si_5非晶态合金退火脆化与晶化之间的联系。  相似文献   

3.
本文应用四端电位法测量了Fe_(82)B_(18-x)Si_x(x=2,4,6,8,10)合金的电阻率随温度的变化,确定由非晶态向晶态转变过程的转变温度,研究该合金中Si 含量对晶化的影响。应用Hesse 方法研究了Fe_(80)B_(20)和Fe_(82)B_(18-x)Si_x 非晶态合金的超精细场分布,得出在各种不同B、Si 浓度下平均超精细场的变化曲线。应用剥谱技术分析Fe_(80)B_(20)和Fe_(82)B_(18-x)Si_x 合金完全晶化后的相结构。  相似文献   

4.
本文研究了 Fe_(80)B_(20)-xSix 系列非晶态合金中 B、Si 元素含量对合金退火脆化行为的影响.在非晶态 Fe_(80)B_(20)-xSix 系列合金中,B、Si 含量分别为11.5at%和8.5at%的合金具有最小的退火脆化敏感性,但其脆化仍发生于晶化开始之前.  相似文献   

5.
本文研究Fe_(80)B_(20-x)Si_x(x=6,8,10,12)非晶态合金的退火脆性规律,给出了合金成分原料纯度,薄带厚度以及薄带表面状态对非晶态合金退火脆性的影响。铁基非晶态合金在低温退火过程中已明显变脆。这种退火脆性是由非晶态合金亚稳特性决定的结构弛豫所致。  相似文献   

6.
用超声波脉冲透射技术获得了三元非晶态合金(Fe_(100-x)M_x)_(83)B_(17)和二元非晶态合金Zr_(100-x)M_x的声速,并确定了它们的杨氏模量。对于前者合金元素M指Cr,Mo,W,Zr和Co;对于后者指Fe,Ni和Co。文中讨论了声速与组分的原子百分数含量x之间的关系,并讨论了近程有序,合金元素密度以及不同尺寸原子之间的随机堆砌引起的致密化等对声速的影响。  相似文献   

7.
本文为作者理学博士论文(日本东北大学,1982年)的概要,讨论非晶态铁磁体的磁体积效应、自旋波激发、因瓦合金的原子结构及磁结构,提出:因瓦效应的起因在于使其铁磁性变为不稳定的电子结构。  相似文献   

8.
用毕特粉紋技术研究了軋辊淬火法制备的非晶态(Fe_xNi_(1-x))_(78)Si_5B_(14)和Fe_(40)Ni_(40)P_(14)B_6合金的磁畴結构,在这些合金样品表面观察到畴壁垂直軋向的磁畴。畴結构主要与从熔态合金淬火过程产生的不均勻单軸各向异性有关。这种各向异性是通过正磁致伸縮与样品的内应力间的磁弹性耦合产生的。样品經退火或磁退火后,这种类型畴的数量随退火温度增加而减少,导致磁化率和剩磁增加。在非晶态Fe_(40)Ni_(40)P_(14)B_6合金样品表面还观察到少量指紋状“迷陣”畴。内应力对磁畴結构影响非常明显。我們观察了針孔和剪口附近的畴結构。  相似文献   

9.
本文用非晶直条带样品居里温度测量装置测量了(Fe_(90)Cr_(10))_(78)B_(10)Si_(12)非晶合金居里温度的热处理效应。通过计算机拟合,得到相对于淬态合金的居里温度增值与退火时间的对数关系,并讨论了结构弛豫引起居里温度变化的两个过程。  相似文献   

10.
非晶态(Fe_(80)Ni_(20))_(78)Si_(22-x)B_x合金的磁各向异性和磁致伸缩随B元素含量的增加和Si元素含量的相对减少而缓慢降低。居里温度和磁矩却呈现出缓慢增高的变化趋势。非晶态合金带的表面状态条纹效应是引起宏观磁各向异性的重要因素之一。对于上述实验现象本文应用退磁效应、分子场近似和电子转移模型等理论予以定性解释。  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

14.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

15.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

16.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

17.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

18.
For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the  相似文献   

19.
<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with  相似文献   

20.
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