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排序方式: 共有2276条查询结果,搜索用时 15 毫秒
101.
HUI XiDong XU ZhiYi WU Yuan CHEN XiaoHua LIU XiongJun & LU ZhaoPing State Key Laboratory for Advanced Metals Materials University of Science Technology Beijing Beijing China 《科学通报(英文版)》2011,(36)
A series of Er-Al-Co bulk metallic glasses (BMGs) have been prepared by the copper mold casting method. The glass forming ability and magnetocaloric effect (MCE) for these alloys have been investigated. The second-order magnetic transition from para-magnetic to ferromagnetic states takes place at about 9 K. These BMGs exhibit excellent MCE because of their large effective magneton number; Er56Al24Co20 BMG has a maximum entropy change and refrigeration capacity of 16.06 J kg-1 K-1 and 546 J kg-1,respectively... 相似文献
102.
提出了2种沥青混合料中酸性石料的改性方法,通过分析试验结果数据,对比研究了改性前后沥青混合料的各项指标情况,提出了常见问题的处理措施,为解决我国沥青混合料中大量使用花岗岩、砂岩等酸性石料的方法提供了依据。 相似文献
103.
104.
基于回答集语义的逻辑程序(ASP)是一种描述性问题求解的典范,目前人们提出了各种ASP的扩张。本文提出带背景理论的回答集程序设计框架,它不仅是正规逻辑程序的一般化,对带聚合函数的ASP而言,也与SPT—PDB的回答集语义一致。经证明,当背景理论是命题逻辑时,该框架与Shen和You提出的方法一致。 相似文献
105.
A larger-scale Zr70Pd30 alloy system has been simulated using molecular dynamics (MD) to investigate structure evolution in Zr70Pd30 metallic glass. The simulated pair distribution function of Zr70Pd30 metallic glass agrees well with the experimental results. Voronoi polyhedron analysis indicates that the icosahedra are not
randomly distributed in space, but form characteristic intercrossed icosahedral clusters with medium-range order. Intercrossed
icosahedral clusters are the dominant local configurations in Zr70Pd30 metallic glass and probably cause the quasicrystalline phase discovered in Zr70Pd30 metallic glass. 相似文献
106.
Aditya M. Vora 《Central European Journal of Physics》2008,6(2):253-262
The theoretical investigations of the superconducting state parameters (SSP) viz. electron-phonon coupling strength λ, Coulomb pseudopotential μ*, transition temperature T
C
, isotope effect exponent α and effective interaction strength N
O
V of six binary La100-C
Ga
C
(C = 16, 20, 22, 24, 26 and 28 at. %) metallic glasses have been reported using Ashcroft’s empty core (EMC) model potential
for the first time. Five local field correction functions proposed by Hartree (H), Taylor (T), Ichimaru-Utsumi (IU), Farid
et al. (F) and Sarkar et al. (S) are used in the present investigation to study the screening influence on the aforesaid properties. It is observed that
the electron-phonon coupling strength λ and the transition temperature T
C
are quite sensitive to the selection of the local field correction functions, whereas the Coulomb pseudopotential μ*, isotope effect exponent α and effective interaction strength N
O
V show weak dependences on the local field correction functions. The T
C
obtained from H-local field correction function are found in qualitative agreement with available experimental data and show
almost linear nature with the concentration (C) of ‘Ga’ element. A linear T
C
equation is proposed by fitting the present outcomes for H-local field correction function, which is in conformity with other
results for the experimental data. Also, the present results are found to be in qualitative agreement with other such earlier
reported data, which confirms the superconducting phase in the metallic glasses.
相似文献
107.
Pd80+x
Si20−x
(x = 0, 1, and 2) binary metallic glasses with the diameter ranging from 7 to 8 mm were prepared by a combination of fluxing
and water quenching or air cooling. Thermal analysis results show that with increasing Si content, the glass transition temperature
T
g, the initial crystallization temperature T
x and the onset crystallization temperature T
p of Pd-Si binary glassy alloys increase. Moreover, the supercooled liquid region reaches 61 K. It indicates that Pd-Si binary
alloys possess large glass forming ability, which can be greatly improved by fluxing treatment.
Supported by the National Basic Research Program of China (Grant No. 2007CB613905) and the National Natural Science Foundation
of China (Grant Nos. 50671050 and 50431030) 相似文献
108.
Aditya M. Vora 《Central European Journal of Physics》2008,6(2):238-252
Ashcroft’s empty core (EMC) model potential is used to study the superconducting state parameters (SSPs) viz. electron-phonon
coupling strength λ, Coulomb pseudopotential μ*, transition temperature T
C
, isotope effect exponent αand effective interaction strength N
O
V of some binary metallic glasses based on the superconducting (S), conditional superconducting (S’) and non-superconducting
(NS) elements of the periodic table. Five local field correction functions proposed by Hartree (H), Taylor (T), Ichimaru-Utsumi
(IU), Farid et al. (F) and Sarkar et al. (S) are used for the first time with EMC potential in the present investigation to study the screening influence on the aforesaid
properties. The T
C
obtained from the H-local field correction function are in excellent agreement with available theoretical or experimental
data. In the present computation, the use of the pseudo-alloy-atom model (PAA) was proposed and found successful. Present
work results are in qualitative agreement with such earlier reported experimental values which confirm the superconducting
phase in all metallic glasses. A strong dependency of the SSPs of the metallic glasses on the valence ‘Z’ is identified.
相似文献
109.
胺中丙烯酸共聚物在水/助溶剂中的溶解性随着共聚物组成中丙烯酸含量的改变而变化。当共聚物申丙烯酸的含量从10mol%增加到50mol%时,共聚物一水/助溶剂体系的粘度一浓度曲线从“N”形经“反S”形过渡到直线形。这一变化和溶液形态的研究结果表明,胺中和丙烯酸共聚物在水/助溶剂中是可以溶解的,并且其溶解性随着共聚物中羧基含量的增加而提高。 相似文献
110.
研究了路用钢纤维砼(SFRC)抗折与疲劳性能,分析了纤维体积率(V_(sf))和长径比(l_(sf)/d_(sf))对抗折和疲劳性能的影响规律,提出并讨论了可供设计应用的SFRC疲劳方程。通过结构形成与破坏过程的分析,探讨了SFRC破坏机理。用SFRC疲劳方程计算了各级路面厚度。实验研究与工程实践表明,路用SFRC的V_(sf)以1~1.2%比较经济合理,据此设计的路面厚度与普通砼相比可减小40%左右,缩缝间距有可能延长至35m以上. 相似文献